ETH Price: $2,050.93 (-1.25%)

Transaction Decoder

Block:
22185003 at Apr-03-2025 01:07:11 AM +UTC
Transaction Fee:
0.000156971710161075 ETH $0.32
Gas Used:
302,975 Gas / 0.518101197 Gwei

Emitted Events:

2085 TetherToken.Transfer( from=0xC2F87CC010DDED46e5B2c8fd4cf884f1F4d836cC, to=[Receiver] 0x22863c875e6b7519141cb8394f2220fac7e6ade6, value=100000000 )
2086 SafeguardPool.Quote( digest=BDA2EDCA42D364C399DFD1D86F426FB5E1FBB4917705FF97D421CABC6F3BAB87, amountIn18Decimals=100000000000000000000, amountOut18Decimals=55051894101856432 )
2087 Vault.Swap( poolId=315A892A4D02C5C1169D5F0E4F7CB4130CC0D138000200000000000000000009, tokenIn=[Receiver] TetherToken, tokenOut=WETH9, amountIn=100000000, amountOut=55051894101856432 )
2088 TetherToken.Transfer( from=[Receiver] 0x22863c875e6b7519141cb8394f2220fac7e6ade6, to=Vault, value=100000000 )
2089 WETH9.Withdrawal( src=Vault, wad=55051894101856432 )
2090 V2DutchOrderReactor.Fill( orderHash=C484B3E3A82F2928300A168861742BDE6D9756F9630669A9E5A951FF51A2617B, filler=[Receiver] 0x22863c875e6b7519141cb8394f2220fac7e6ade6, swapper=0xC2F87CC010DDED46e5B2c8fd4cf884f1F4d836cC, nonce=1993351574143891174572433905560589861365753739206311271527256259818498603270 )

Account State Difference:

  Address   Before After State Difference Code
0x00000000...43aC78BA3
(Uniswap Protocol: Permit2)
0x000000fe...05F2E7E1c
(Uniswap: Fee Collector)
0.087232749140189323 Eth0.08736980102301241 Eth0.000137051882823087
0x22863c87...AC7e6Ade6 0.226754152772089219 Eth0.226902943968569219 Eth0.00014879119648
0x315a892a...30Cc0d138
0x6b270F0B...Da9da8c93
3.480047893560865022 Eth
Nonce: 10382
3.479890921850703947 Eth
Nonce: 10383
0.000156971710161075
(beaverbuild)
6.689677708839816891 Eth6.689677945615082366 Eth0.000000236775265475
0xC02aaA39...83C756Cc2 2,845,425.495474648023968816 Eth2,845,425.440422753922112384 Eth0.055051894101856432
0xC2F87CC0...1F4d836cC 0.002630574018265469 Eth0.057396625040818814 Eth0.054766051022553345
0xd315a9C3...528C76293
(Swaap Finance: Vault)
0xdAC17F95...13D831ec7

Execution Trace

0x22863c875e6b7519141cb8394f2220fac7e6ade6.bcf88f1e( )
  • 0x6e9359dd27980fb7027c179ae5e701e4bcb2f6b9.bcf88f1e( )
    • V2DutchOrderReactor.executeWithCallback( order=[{name:order, type:bytes, order:1, indexed:false, value: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valueString: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}, {name:sig, type:bytes, order:2, indexed:false, value:0x1DD6B4DAD99A252BFD5502115B6692FBEC5B37622445746B3BCA0A2ED7DD54586E8FDE6E48480A30D4E2710A93491F339B809763B0B84959F7E8FDAFFD268CF41B, valueString:0x1DD6B4DAD99A252BFD5502115B6692FBEC5B37622445746B3BCA0A2ED7DD54586E8FDE6E48480A30D4E2710A93491F339B809763B0B84959F7E8FDAFFD268CF41B}], callbackData=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
      • Null: 0x000...001.45ce5236( )
      • Permit2.permitWitnessTransferFrom( permit=[{name:permitted, type:tuple, order:1, indexed:false, value:[{name:token, type:address, order:1, indexed:false, value:0xdAC17F958D2ee523a2206206994597C13D831ec7, valueString:0xdAC17F958D2ee523a2206206994597C13D831ec7}, {name:amount, type:uint256, order:2, indexed:false, value:100000000, valueString:100000000}], valueString:[{name:token, type:address, order:1, indexed:false, value:0xdAC17F958D2ee523a2206206994597C13D831ec7, valueString:0xdAC17F958D2ee523a2206206994597C13D831ec7}, {name:amount, type:uint256, order:2, indexed:false, value:100000000, valueString:100000000}]}, {name:nonce, type:uint256, order:2, indexed:false, value:1993351574143891174572433905560589861365753739206311271527256259818498603270, valueString:1993351574143891174572433905560589861365753739206311271527256259818498603270}, {name:deadline, type:uint256, order:3, indexed:false, value:1743642712, valueString:1743642712}], transferDetails=[{name:to, type:address, order:1, indexed:false, value:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, valueString:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6}, {name:requestedAmount, type:uint256, order:2, indexed:false, value:100000000, valueString:100000000}], owner=0xC2F87CC010DDED46e5B2c8fd4cf884f1F4d836cC, witness=C484B3E3A82F2928300A168861742BDE6D9756F9630669A9E5A951FF51A2617B, witnessTypeString=V2DutchOrder witness)DutchOutput(address token,uint256 startAmount,uint256 endAmount,address recipient)OrderInfo(address reactor,address swapper,uint256 nonce,uint256 deadline,address additionalValidationContract,bytes additionalValidationData)TokenPermissions(address token,uint256 amount)V2DutchOrder(OrderInfo info,address cosigner,address baseInputToken,uint256 baseInputStartAmount,uint256 baseInputEndAmount,DutchOutput[] baseOutputs), signature=0x1DD6B4DAD99A252BFD5502115B6692FBEC5B37622445746B3BCA0A2ED7DD54586E8FDE6E48480A30D4E2710A93491F339B809763B0B84959F7E8FDAFFD268CF41B )
        • Null: 0x000...001.fb1a5b41( )
        • TetherToken.transferFrom( _from=0xC2F87CC010DDED46e5B2c8fd4cf884f1F4d836cC, _to=0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, _value=100000000 )
        • 0x22863c875e6b7519141cb8394f2220fac7e6ade6.585da628( )
          • 0x6e9359dd27980fb7027c179ae5e701e4bcb2f6b9.585da628( )
            • TetherToken.allowance( _owner=0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, _spender=0xd315a9C38eC871068FEC378E4Ce78AF528C76293 ) => ( remaining=115792089237316195423570985008687907853269984665640564039457584007913129639935 )
            • Vault.swap( singleSwap=[{name:poolId, type:bytes32, order:1, indexed:false, value:315A892A4D02C5C1169D5F0E4F7CB4130CC0D138000200000000000000000009, valueString:315A892A4D02C5C1169D5F0E4F7CB4130CC0D138000200000000000000000009}, {name:kind, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:assetIn, type:address, order:3, indexed:false, value:0xdAC17F958D2ee523a2206206994597C13D831ec7, valueString:0xdAC17F958D2ee523a2206206994597C13D831ec7}, {name:assetOut, type:address, order:4, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:amount, type:uint256, order:5, indexed:false, value:100000000, valueString:100000000}, {name:userData, type:bytes, order:6, indexed:false, value: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valueString: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}], funds=[{name:sender, type:address, order:1, indexed:false, value:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, valueString:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6}, {name:fromInternalBalance, type:bool, order:2, indexed:false, value:false, valueString:False}, {name:recipient, type:address, order:3, indexed:false, value:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, valueString:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6}, {name:toInternalBalance, type:bool, order:4, indexed:false, value:false, valueString:False}], limit=54903102905376432, deadline=1743642542 ) => ( amountCalculated=55051894101856432 )
              • SafeguardPool.onSwap( request=[{name:kind, type:uint8, order:1, indexed:false, value:0, valueString:0}, {name:tokenIn, type:address, order:2, indexed:false, value:0xdAC17F958D2ee523a2206206994597C13D831ec7, valueString:0xdAC17F958D2ee523a2206206994597C13D831ec7}, {name:tokenOut, type:address, order:3, indexed:false, value:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, valueString:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2}, {name:amount, type:uint256, order:4, indexed:false, value:100000000, valueString:100000000}, {name:poolId, type:bytes32, order:5, indexed:false, value:315A892A4D02C5C1169D5F0E4F7CB4130CC0D138000200000000000000000009, valueString:315A892A4D02C5C1169D5F0E4F7CB4130CC0D138000200000000000000000009}, {name:lastChangeBlock, type:uint256, order:6, indexed:false, value:22184963, valueString:22184963}, {name:from, type:address, order:7, indexed:false, value:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, valueString:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6}, {name:to, type:address, order:8, indexed:false, value:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, valueString:0x22863c875e6b7519141CB8394f2220FAC7e6Ade6}, {name:userData, type:bytes, order:9, indexed:false, value: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valueString:0x000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000001800000000000000000000000000000000000000000000000000006312711E489690000000000000000000000000000000000000000000000000000000067EDDFAE00000000000000000000000000000000000000000000000000000000000000E00000000000000000000000006B270F0BA52908399170B0D4BDDC8A5DA9DA8C9300000000000000000000000000000000000000000000000000000000000000000000000000000062788E744379C80AD0000000000000000579A814E10A7400000000000000007EEA834FA38EFDD5400000000000000000114FC0EB647EB2125100000000000000000000000000000000000000000014594617D9DC364210000000000000000000004563918244F400000000000000000000006A94D74F43000000000000000000000000000067EDDF310000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000410D590D638C3B14C75FAA26168069096EADA48B671BD452BEEA8CF0CF8DAFFBF67E14B31FE88AA2EF1A1672ED9C58D92CC33DEC325302627817F35874DEF05FED1B00000000000000000000000000000000000000000000000000000000000000}], balanceTokenIn=599344176916, balanceTokenOut=319341501194441986641 ) => ( 55051894101856432 )
              • TetherToken.transferFrom( _from=0x22863c875e6b7519141CB8394f2220FAC7e6Ade6, _to=0xd315a9C38eC871068FEC378E4Ce78AF528C76293, _value=100000000 )
              • WETH9.withdraw( wad=55051894101856432 )
              • ETH 0.055051894101856432 0x22863c875e6b7519141cb8394f2220fac7e6ade6.CALL( )
              • ETH 0.054903102905376432 V2DutchOrderReactor.CALL( )
              • ETH 0.054766051022553345 0xc2f87cc010dded46e5b2c8fd4cf884f1f4d836cc.CALL( )
              • ETH 0.000137051882823087 FeeCollector.CALL( )
                File 1 of 7: TetherToken
                pragma solidity ^0.4.17;
                
                /**
                 * @title SafeMath
                 * @dev Math operations with safety checks that throw on error
                 */
                library SafeMath {
                    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                        if (a == 0) {
                            return 0;
                        }
                        uint256 c = a * b;
                        assert(c / a == b);
                        return c;
                    }
                
                    function div(uint256 a, uint256 b) internal pure returns (uint256) {
                        // assert(b > 0); // Solidity automatically throws when dividing by 0
                        uint256 c = a / b;
                        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                        return c;
                    }
                
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        assert(b <= a);
                        return a - b;
                    }
                
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a + b;
                        assert(c >= a);
                        return c;
                    }
                }
                
                /**
                 * @title Ownable
                 * @dev The Ownable contract has an owner address, and provides basic authorization control
                 * functions, this simplifies the implementation of "user permissions".
                 */
                contract Ownable {
                    address public owner;
                
                    /**
                      * @dev The Ownable constructor sets the original `owner` of the contract to the sender
                      * account.
                      */
                    function Ownable() public {
                        owner = msg.sender;
                    }
                
                    /**
                      * @dev Throws if called by any account other than the owner.
                      */
                    modifier onlyOwner() {
                        require(msg.sender == owner);
                        _;
                    }
                
                    /**
                    * @dev Allows the current owner to transfer control of the contract to a newOwner.
                    * @param newOwner The address to transfer ownership to.
                    */
                    function transferOwnership(address newOwner) public onlyOwner {
                        if (newOwner != address(0)) {
                            owner = newOwner;
                        }
                    }
                
                }
                
                /**
                 * @title ERC20Basic
                 * @dev Simpler version of ERC20 interface
                 * @dev see https://github.com/ethereum/EIPs/issues/20
                 */
                contract ERC20Basic {
                    uint public _totalSupply;
                    function totalSupply() public constant returns (uint);
                    function balanceOf(address who) public constant returns (uint);
                    function transfer(address to, uint value) public;
                    event Transfer(address indexed from, address indexed to, uint value);
                }
                
                /**
                 * @title ERC20 interface
                 * @dev see https://github.com/ethereum/EIPs/issues/20
                 */
                contract ERC20 is ERC20Basic {
                    function allowance(address owner, address spender) public constant returns (uint);
                    function transferFrom(address from, address to, uint value) public;
                    function approve(address spender, uint value) public;
                    event Approval(address indexed owner, address indexed spender, uint value);
                }
                
                /**
                 * @title Basic token
                 * @dev Basic version of StandardToken, with no allowances.
                 */
                contract BasicToken is Ownable, ERC20Basic {
                    using SafeMath for uint;
                
                    mapping(address => uint) public balances;
                
                    // additional variables for use if transaction fees ever became necessary
                    uint public basisPointsRate = 0;
                    uint public maximumFee = 0;
                
                    /**
                    * @dev Fix for the ERC20 short address attack.
                    */
                    modifier onlyPayloadSize(uint size) {
                        require(!(msg.data.length < size + 4));
                        _;
                    }
                
                    /**
                    * @dev transfer token for a specified address
                    * @param _to The address to transfer to.
                    * @param _value The amount to be transferred.
                    */
                    function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
                        uint fee = (_value.mul(basisPointsRate)).div(10000);
                        if (fee > maximumFee) {
                            fee = maximumFee;
                        }
                        uint sendAmount = _value.sub(fee);
                        balances[msg.sender] = balances[msg.sender].sub(_value);
                        balances[_to] = balances[_to].add(sendAmount);
                        if (fee > 0) {
                            balances[owner] = balances[owner].add(fee);
                            Transfer(msg.sender, owner, fee);
                        }
                        Transfer(msg.sender, _to, sendAmount);
                    }
                
                    /**
                    * @dev Gets the balance of the specified address.
                    * @param _owner The address to query the the balance of.
                    * @return An uint representing the amount owned by the passed address.
                    */
                    function balanceOf(address _owner) public constant returns (uint balance) {
                        return balances[_owner];
                    }
                
                }
                
                /**
                 * @title Standard ERC20 token
                 *
                 * @dev Implementation of the basic standard token.
                 * @dev https://github.com/ethereum/EIPs/issues/20
                 * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
                 */
                contract StandardToken is BasicToken, ERC20 {
                
                    mapping (address => mapping (address => uint)) public allowed;
                
                    uint public constant MAX_UINT = 2**256 - 1;
                
                    /**
                    * @dev Transfer tokens from one address to another
                    * @param _from address The address which you want to send tokens from
                    * @param _to address The address which you want to transfer to
                    * @param _value uint the amount of tokens to be transferred
                    */
                    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
                        var _allowance = allowed[_from][msg.sender];
                
                        // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
                        // if (_value > _allowance) throw;
                
                        uint fee = (_value.mul(basisPointsRate)).div(10000);
                        if (fee > maximumFee) {
                            fee = maximumFee;
                        }
                        if (_allowance < MAX_UINT) {
                            allowed[_from][msg.sender] = _allowance.sub(_value);
                        }
                        uint sendAmount = _value.sub(fee);
                        balances[_from] = balances[_from].sub(_value);
                        balances[_to] = balances[_to].add(sendAmount);
                        if (fee > 0) {
                            balances[owner] = balances[owner].add(fee);
                            Transfer(_from, owner, fee);
                        }
                        Transfer(_from, _to, sendAmount);
                    }
                
                    /**
                    * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
                    * @param _spender The address which will spend the funds.
                    * @param _value The amount of tokens to be spent.
                    */
                    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
                
                        // To change the approve amount you first have to reduce the addresses`
                        //  allowance to zero by calling `approve(_spender, 0)` if it is not
                        //  already 0 to mitigate the race condition described here:
                        //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                        require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));
                
                        allowed[msg.sender][_spender] = _value;
                        Approval(msg.sender, _spender, _value);
                    }
                
                    /**
                    * @dev Function to check the amount of tokens than an owner allowed to a spender.
                    * @param _owner address The address which owns the funds.
                    * @param _spender address The address which will spend the funds.
                    * @return A uint specifying the amount of tokens still available for the spender.
                    */
                    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                        return allowed[_owner][_spender];
                    }
                
                }
                
                
                /**
                 * @title Pausable
                 * @dev Base contract which allows children to implement an emergency stop mechanism.
                 */
                contract Pausable is Ownable {
                  event Pause();
                  event Unpause();
                
                  bool public paused = false;
                
                
                  /**
                   * @dev Modifier to make a function callable only when the contract is not paused.
                   */
                  modifier whenNotPaused() {
                    require(!paused);
                    _;
                  }
                
                  /**
                   * @dev Modifier to make a function callable only when the contract is paused.
                   */
                  modifier whenPaused() {
                    require(paused);
                    _;
                  }
                
                  /**
                   * @dev called by the owner to pause, triggers stopped state
                   */
                  function pause() onlyOwner whenNotPaused public {
                    paused = true;
                    Pause();
                  }
                
                  /**
                   * @dev called by the owner to unpause, returns to normal state
                   */
                  function unpause() onlyOwner whenPaused public {
                    paused = false;
                    Unpause();
                  }
                }
                
                contract BlackList is Ownable, BasicToken {
                
                    /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
                    function getBlackListStatus(address _maker) external constant returns (bool) {
                        return isBlackListed[_maker];
                    }
                
                    function getOwner() external constant returns (address) {
                        return owner;
                    }
                
                    mapping (address => bool) public isBlackListed;
                    
                    function addBlackList (address _evilUser) public onlyOwner {
                        isBlackListed[_evilUser] = true;
                        AddedBlackList(_evilUser);
                    }
                
                    function removeBlackList (address _clearedUser) public onlyOwner {
                        isBlackListed[_clearedUser] = false;
                        RemovedBlackList(_clearedUser);
                    }
                
                    function destroyBlackFunds (address _blackListedUser) public onlyOwner {
                        require(isBlackListed[_blackListedUser]);
                        uint dirtyFunds = balanceOf(_blackListedUser);
                        balances[_blackListedUser] = 0;
                        _totalSupply -= dirtyFunds;
                        DestroyedBlackFunds(_blackListedUser, dirtyFunds);
                    }
                
                    event DestroyedBlackFunds(address _blackListedUser, uint _balance);
                
                    event AddedBlackList(address _user);
                
                    event RemovedBlackList(address _user);
                
                }
                
                contract UpgradedStandardToken is StandardToken{
                    // those methods are called by the legacy contract
                    // and they must ensure msg.sender to be the contract address
                    function transferByLegacy(address from, address to, uint value) public;
                    function transferFromByLegacy(address sender, address from, address spender, uint value) public;
                    function approveByLegacy(address from, address spender, uint value) public;
                }
                
                contract TetherToken is Pausable, StandardToken, BlackList {
                
                    string public name;
                    string public symbol;
                    uint public decimals;
                    address public upgradedAddress;
                    bool public deprecated;
                
                    //  The contract can be initialized with a number of tokens
                    //  All the tokens are deposited to the owner address
                    //
                    // @param _balance Initial supply of the contract
                    // @param _name Token Name
                    // @param _symbol Token symbol
                    // @param _decimals Token decimals
                    function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
                        _totalSupply = _initialSupply;
                        name = _name;
                        symbol = _symbol;
                        decimals = _decimals;
                        balances[owner] = _initialSupply;
                        deprecated = false;
                    }
                
                    // Forward ERC20 methods to upgraded contract if this one is deprecated
                    function transfer(address _to, uint _value) public whenNotPaused {
                        require(!isBlackListed[msg.sender]);
                        if (deprecated) {
                            return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
                        } else {
                            return super.transfer(_to, _value);
                        }
                    }
                
                    // Forward ERC20 methods to upgraded contract if this one is deprecated
                    function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
                        require(!isBlackListed[_from]);
                        if (deprecated) {
                            return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
                        } else {
                            return super.transferFrom(_from, _to, _value);
                        }
                    }
                
                    // Forward ERC20 methods to upgraded contract if this one is deprecated
                    function balanceOf(address who) public constant returns (uint) {
                        if (deprecated) {
                            return UpgradedStandardToken(upgradedAddress).balanceOf(who);
                        } else {
                            return super.balanceOf(who);
                        }
                    }
                
                    // Forward ERC20 methods to upgraded contract if this one is deprecated
                    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
                        if (deprecated) {
                            return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
                        } else {
                            return super.approve(_spender, _value);
                        }
                    }
                
                    // Forward ERC20 methods to upgraded contract if this one is deprecated
                    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                        if (deprecated) {
                            return StandardToken(upgradedAddress).allowance(_owner, _spender);
                        } else {
                            return super.allowance(_owner, _spender);
                        }
                    }
                
                    // deprecate current contract in favour of a new one
                    function deprecate(address _upgradedAddress) public onlyOwner {
                        deprecated = true;
                        upgradedAddress = _upgradedAddress;
                        Deprecate(_upgradedAddress);
                    }
                
                    // deprecate current contract if favour of a new one
                    function totalSupply() public constant returns (uint) {
                        if (deprecated) {
                            return StandardToken(upgradedAddress).totalSupply();
                        } else {
                            return _totalSupply;
                        }
                    }
                
                    // Issue a new amount of tokens
                    // these tokens are deposited into the owner address
                    //
                    // @param _amount Number of tokens to be issued
                    function issue(uint amount) public onlyOwner {
                        require(_totalSupply + amount > _totalSupply);
                        require(balances[owner] + amount > balances[owner]);
                
                        balances[owner] += amount;
                        _totalSupply += amount;
                        Issue(amount);
                    }
                
                    // Redeem tokens.
                    // These tokens are withdrawn from the owner address
                    // if the balance must be enough to cover the redeem
                    // or the call will fail.
                    // @param _amount Number of tokens to be issued
                    function redeem(uint amount) public onlyOwner {
                        require(_totalSupply >= amount);
                        require(balances[owner] >= amount);
                
                        _totalSupply -= amount;
                        balances[owner] -= amount;
                        Redeem(amount);
                    }
                
                    function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
                        // Ensure transparency by hardcoding limit beyond which fees can never be added
                        require(newBasisPoints < 20);
                        require(newMaxFee < 50);
                
                        basisPointsRate = newBasisPoints;
                        maximumFee = newMaxFee.mul(10**decimals);
                
                        Params(basisPointsRate, maximumFee);
                    }
                
                    // Called when new token are issued
                    event Issue(uint amount);
                
                    // Called when tokens are redeemed
                    event Redeem(uint amount);
                
                    // Called when contract is deprecated
                    event Deprecate(address newAddress);
                
                    // Called if contract ever adds fees
                    event Params(uint feeBasisPoints, uint maxFee);
                }

                File 2 of 7: SafeguardPool
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                library BasePoolUserData {
                    // Special ExitKind for all pools, used in Recovery Mode. Use the max 8-bit value to prevent conflicts
                    // with future additions to the ExitKind enums (or any front-end code that maps to existing values)
                    uint8 public constant RECOVERY_MODE_EXIT_KIND = 255;
                    // Return true if this is the special exit kind.
                    function isRecoveryModeExitKind(bytes memory self) internal pure returns (bool) {
                        // Check for the "no data" case, or abi.decode would revert
                        return self.length > 0 && abi.decode(self, (uint8)) == RECOVERY_MODE_EXIT_KIND;
                    }
                    // Parse the bptAmountIn out of the userData
                    function recoveryModeExit(bytes memory self) internal pure returns (uint256 bptAmountIn) {
                        (, bptAmountIn) = abi.decode(self, (uint8, uint256));
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                interface IControlledPool {
                    function setSwapFeePercentage(uint256 swapFeePercentage) external;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface for the RecoveryMode module.
                 */
                interface IRecoveryMode {
                    /**
                     * @dev Emitted when the Recovery Mode status changes.
                     */
                    event RecoveryModeStateChanged(bool enabled);
                    /**
                     * @notice Enables Recovery Mode in the Pool, disabling protocol fee collection and allowing for safe proportional
                     * exits with low computational complexity and no dependencies.
                     */
                    function enableRecoveryMode() external;
                    /**
                     * @notice Disables Recovery Mode in the Pool, restoring protocol fee collection and disallowing proportional exits.
                     */
                    function disableRecoveryMode() external;
                    /**
                     * @notice Returns true if the Pool is in Recovery Mode.
                     */
                    function inRecoveryMode() external view returns (bool);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                // solhint-disable
                /**
                 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
                 * supported.
                 * Uses the default 'BAL' prefix for the error code
                 */
                function _require(bool condition, uint256 errorCode) pure {
                    if (!condition) _revert(errorCode);
                }
                /**
                 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
                 * supported.
                 */
                function _require(
                    bool condition,
                    uint256 errorCode,
                    bytes3 prefix
                ) pure {
                    if (!condition) _revert(errorCode, prefix);
                }
                /**
                 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
                 * Uses the default 'BAL' prefix for the error code
                 */
                function _revert(uint256 errorCode) pure {
                    _revert(errorCode, 0x42414c); // This is the raw byte representation of "BAL"
                }
                /**
                 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
                 */
                function _revert(uint256 errorCode, bytes3 prefix) pure {
                    uint256 prefixUint = uint256(uint24(prefix));
                    // We're going to dynamically create a revert string based on the error code, with the following format:
                    // 'BAL#{errorCode}'
                    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
                    //
                    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
                    // number (8 to 16 bits) than the individual string characters.
                    //
                    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
                    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
                    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
                    assembly {
                        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
                        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
                        // the '0' character.
                        let units := add(mod(errorCode, 10), 0x30)
                        errorCode := div(errorCode, 10)
                        let tenths := add(mod(errorCode, 10), 0x30)
                        errorCode := div(errorCode, 10)
                        let hundreds := add(mod(errorCode, 10), 0x30)
                        // With the individual characters, we can now construct the full string.
                        // We first append the '#' character (0x23) to the prefix. In the case of 'BAL', it results in 0x42414c23 ('BAL#')
                        // Then, we shift this by 24 (to provide space for the 3 bytes of the error code), and add the
                        // characters to it, each shifted by a multiple of 8.
                        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
                        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
                        // array).
                        let formattedPrefix := shl(24, add(0x23, shl(8, prefixUint)))
                        let revertReason := shl(200, add(formattedPrefix, add(add(units, shl(8, tenths)), shl(16, hundreds))))
                        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
                        // message will have the following layout:
                        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
                        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
                        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
                        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
                        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
                        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
                        // The string length is fixed: 7 characters.
                        mstore(0x24, 7)
                        // Finally, the string itself is stored.
                        mstore(0x44, revertReason)
                        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
                        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
                        revert(0, 100)
                    }
                }
                library Errors {
                    // Math
                    uint256 internal constant ADD_OVERFLOW = 0;
                    uint256 internal constant SUB_OVERFLOW = 1;
                    uint256 internal constant SUB_UNDERFLOW = 2;
                    uint256 internal constant MUL_OVERFLOW = 3;
                    uint256 internal constant ZERO_DIVISION = 4;
                    uint256 internal constant DIV_INTERNAL = 5;
                    uint256 internal constant X_OUT_OF_BOUNDS = 6;
                    uint256 internal constant Y_OUT_OF_BOUNDS = 7;
                    uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
                    uint256 internal constant INVALID_EXPONENT = 9;
                    // Input
                    uint256 internal constant OUT_OF_BOUNDS = 100;
                    uint256 internal constant UNSORTED_ARRAY = 101;
                    uint256 internal constant UNSORTED_TOKENS = 102;
                    uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
                    uint256 internal constant ZERO_TOKEN = 104;
                    uint256 internal constant INSUFFICIENT_DATA = 105;
                    // Shared pools
                    uint256 internal constant MIN_TOKENS = 200;
                    uint256 internal constant MAX_TOKENS = 201;
                    uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
                    uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
                    uint256 internal constant MINIMUM_BPT = 204;
                    uint256 internal constant CALLER_NOT_VAULT = 205;
                    uint256 internal constant UNINITIALIZED = 206;
                    uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
                    uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
                    uint256 internal constant EXPIRED_PERMIT = 209;
                    uint256 internal constant NOT_TWO_TOKENS = 210;
                    uint256 internal constant DISABLED = 211;
                    // Pools
                    uint256 internal constant MIN_AMP = 300;
                    uint256 internal constant MAX_AMP = 301;
                    uint256 internal constant MIN_WEIGHT = 302;
                    uint256 internal constant MAX_STABLE_TOKENS = 303;
                    uint256 internal constant MAX_IN_RATIO = 304;
                    uint256 internal constant MAX_OUT_RATIO = 305;
                    uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
                    uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
                    uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
                    uint256 internal constant INVALID_TOKEN = 309;
                    uint256 internal constant UNHANDLED_JOIN_KIND = 310;
                    uint256 internal constant ZERO_INVARIANT = 311;
                    uint256 internal constant ORACLE_INVALID_SECONDS_QUERY = 312;
                    uint256 internal constant ORACLE_NOT_INITIALIZED = 313;
                    uint256 internal constant ORACLE_QUERY_TOO_OLD = 314;
                    uint256 internal constant ORACLE_INVALID_INDEX = 315;
                    uint256 internal constant ORACLE_BAD_SECS = 316;
                    uint256 internal constant AMP_END_TIME_TOO_CLOSE = 317;
                    uint256 internal constant AMP_ONGOING_UPDATE = 318;
                    uint256 internal constant AMP_RATE_TOO_HIGH = 319;
                    uint256 internal constant AMP_NO_ONGOING_UPDATE = 320;
                    uint256 internal constant STABLE_INVARIANT_DIDNT_CONVERGE = 321;
                    uint256 internal constant STABLE_GET_BALANCE_DIDNT_CONVERGE = 322;
                    uint256 internal constant RELAYER_NOT_CONTRACT = 323;
                    uint256 internal constant BASE_POOL_RELAYER_NOT_CALLED = 324;
                    uint256 internal constant REBALANCING_RELAYER_REENTERED = 325;
                    uint256 internal constant GRADUAL_UPDATE_TIME_TRAVEL = 326;
                    uint256 internal constant SWAPS_DISABLED = 327;
                    uint256 internal constant CALLER_IS_NOT_LBP_OWNER = 328;
                    uint256 internal constant PRICE_RATE_OVERFLOW = 329;
                    uint256 internal constant INVALID_JOIN_EXIT_KIND_WHILE_SWAPS_DISABLED = 330;
                    uint256 internal constant WEIGHT_CHANGE_TOO_FAST = 331;
                    uint256 internal constant LOWER_GREATER_THAN_UPPER_TARGET = 332;
                    uint256 internal constant UPPER_TARGET_TOO_HIGH = 333;
                    uint256 internal constant UNHANDLED_BY_LINEAR_POOL = 334;
                    uint256 internal constant OUT_OF_TARGET_RANGE = 335;
                    uint256 internal constant UNHANDLED_EXIT_KIND = 336;
                    uint256 internal constant UNAUTHORIZED_EXIT = 337;
                    uint256 internal constant MAX_MANAGEMENT_SWAP_FEE_PERCENTAGE = 338;
                    uint256 internal constant UNHANDLED_BY_MANAGED_POOL = 339;
                    uint256 internal constant UNHANDLED_BY_PHANTOM_POOL = 340;
                    uint256 internal constant TOKEN_DOES_NOT_HAVE_RATE_PROVIDER = 341;
                    uint256 internal constant INVALID_INITIALIZATION = 342;
                    uint256 internal constant OUT_OF_NEW_TARGET_RANGE = 343;
                    uint256 internal constant FEATURE_DISABLED = 344;
                    uint256 internal constant UNINITIALIZED_POOL_CONTROLLER = 345;
                    uint256 internal constant SET_SWAP_FEE_DURING_FEE_CHANGE = 346;
                    uint256 internal constant SET_SWAP_FEE_PENDING_FEE_CHANGE = 347;
                    uint256 internal constant CHANGE_TOKENS_DURING_WEIGHT_CHANGE = 348;
                    uint256 internal constant CHANGE_TOKENS_PENDING_WEIGHT_CHANGE = 349;
                    uint256 internal constant MAX_WEIGHT = 350;
                    uint256 internal constant UNAUTHORIZED_JOIN = 351;
                    uint256 internal constant MAX_MANAGEMENT_AUM_FEE_PERCENTAGE = 352;
                    uint256 internal constant FRACTIONAL_TARGET = 353;
                    uint256 internal constant ADD_OR_REMOVE_BPT = 354;
                    uint256 internal constant INVALID_CIRCUIT_BREAKER_BOUNDS = 355;
                    uint256 internal constant CIRCUIT_BREAKER_TRIPPED = 356;
                    uint256 internal constant MALICIOUS_QUERY_REVERT = 357;
                    uint256 internal constant JOINS_EXITS_DISABLED = 358;
                    // Lib
                    uint256 internal constant REENTRANCY = 400;
                    uint256 internal constant SENDER_NOT_ALLOWED = 401;
                    uint256 internal constant PAUSED = 402;
                    uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
                    uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
                    uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
                    uint256 internal constant INSUFFICIENT_BALANCE = 406;
                    uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
                    uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
                    uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
                    uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
                    uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
                    uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
                    uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
                    uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
                    uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
                    uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
                    uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
                    uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
                    uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
                    uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
                    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
                    uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
                    uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
                    uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
                    uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
                    uint256 internal constant CALLER_IS_NOT_OWNER = 426;
                    uint256 internal constant NEW_OWNER_IS_ZERO = 427;
                    uint256 internal constant CODE_DEPLOYMENT_FAILED = 428;
                    uint256 internal constant CALL_TO_NON_CONTRACT = 429;
                    uint256 internal constant LOW_LEVEL_CALL_FAILED = 430;
                    uint256 internal constant NOT_PAUSED = 431;
                    uint256 internal constant ADDRESS_ALREADY_ALLOWLISTED = 432;
                    uint256 internal constant ADDRESS_NOT_ALLOWLISTED = 433;
                    uint256 internal constant ERC20_BURN_EXCEEDS_BALANCE = 434;
                    uint256 internal constant INVALID_OPERATION = 435;
                    uint256 internal constant CODEC_OVERFLOW = 436;
                    uint256 internal constant IN_RECOVERY_MODE = 437;
                    uint256 internal constant NOT_IN_RECOVERY_MODE = 438;
                    uint256 internal constant INDUCED_FAILURE = 439;
                    uint256 internal constant EXPIRED_SIGNATURE = 440;
                    uint256 internal constant MALFORMED_SIGNATURE = 441;
                    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_UINT64 = 442;
                    uint256 internal constant UNHANDLED_FEE_TYPE = 443;
                    uint256 internal constant BURN_FROM_ZERO = 444;
                    // Vault
                    uint256 internal constant INVALID_POOL_ID = 500;
                    uint256 internal constant CALLER_NOT_POOL = 501;
                    uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
                    uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
                    uint256 internal constant INVALID_SIGNATURE = 504;
                    uint256 internal constant EXIT_BELOW_MIN = 505;
                    uint256 internal constant JOIN_ABOVE_MAX = 506;
                    uint256 internal constant SWAP_LIMIT = 507;
                    uint256 internal constant SWAP_DEADLINE = 508;
                    uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
                    uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
                    uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
                    uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
                    uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
                    uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
                    uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
                    uint256 internal constant INSUFFICIENT_ETH = 516;
                    uint256 internal constant UNALLOCATED_ETH = 517;
                    uint256 internal constant ETH_TRANSFER = 518;
                    uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
                    uint256 internal constant TOKENS_MISMATCH = 520;
                    uint256 internal constant TOKEN_NOT_REGISTERED = 521;
                    uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
                    uint256 internal constant TOKENS_ALREADY_SET = 523;
                    uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
                    uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
                    uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
                    uint256 internal constant POOL_NO_TOKENS = 527;
                    uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
                    // Fees
                    uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
                    uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
                    uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
                    uint256 internal constant AUM_FEE_PERCENTAGE_TOO_HIGH = 603;
                    // FeeSplitter
                    uint256 internal constant SPLITTER_FEE_PERCENTAGE_TOO_HIGH = 700;
                    // Misc
                    uint256 internal constant UNIMPLEMENTED = 998;
                    uint256 internal constant SHOULD_NOT_HAPPEN = 999;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                interface IAuthentication {
                    /**
                     * @dev Returns the action identifier associated with the external function described by `selector`.
                     */
                    function getActionId(bytes4 selector) external view returns (bytes32);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
                 */
                interface ISignaturesValidator {
                    /**
                     * @dev Returns the EIP712 domain separator.
                     */
                    function getDomainSeparator() external view returns (bytes32);
                    /**
                     * @dev Returns the next nonce used by an address to sign messages.
                     */
                    function getNextNonce(address user) external view returns (uint256);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface for the TemporarilyPausable helper.
                 */
                interface ITemporarilyPausable {
                    /**
                     * @dev Emitted every time the pause state changes by `_setPaused`.
                     */
                    event PausedStateChanged(bool paused);
                    /**
                     * @dev Returns the current paused state.
                     */
                    function getPausedState()
                        external
                        view
                        returns (
                            bool paused,
                            uint256 pauseWindowEndTime,
                            uint256 bufferPeriodEndTime
                        );
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                import "../openzeppelin/IERC20.sol";
                /**
                 * @dev Interface for WETH9.
                 * See https://github.com/gnosis/canonical-weth/blob/0dd1ea3e295eef916d0c6223ec63141137d22d67/contracts/WETH9.sol
                 */
                interface IWETH is IERC20 {
                    function deposit() external payable;
                    function withdraw(uint256 amount) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface of the ERC20 standard as defined in the EIP.
                 */
                interface IERC20 {
                    /**
                     * @dev Returns the amount of tokens in existence.
                     */
                    function totalSupply() external view returns (uint256);
                    /**
                     * @dev Returns the amount of tokens owned by `account`.
                     */
                    function balanceOf(address account) external view returns (uint256);
                    /**
                     * @dev Moves `amount` tokens from the caller's account to `recipient`.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * Emits a {Transfer} event.
                     */
                    function transfer(address recipient, uint256 amount) external returns (bool);
                    /**
                     * @dev Returns the remaining number of tokens that `spender` will be
                     * allowed to spend on behalf of `owner` through {transferFrom}. This is
                     * zero by default.
                     *
                     * This value changes when {approve} or {transferFrom} are called.
                     */
                    function allowance(address owner, address spender) external view returns (uint256);
                    /**
                     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * IMPORTANT: Beware that changing an allowance with this method brings the risk
                     * that someone may use both the old and the new allowance by unfortunate
                     * transaction ordering. One possible solution to mitigate this race
                     * condition is to first reduce the spender's allowance to 0 and set the
                     * desired value afterwards:
                     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                     *
                     * Emits an {Approval} event.
                     */
                    function approve(address spender, uint256 amount) external returns (bool);
                    /**
                     * @dev Moves `amount` tokens from `sender` to `recipient` using the
                     * allowance mechanism. `amount` is then deducted from the caller's
                     * allowance.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * Emits a {Transfer} event.
                     */
                    function transferFrom(
                        address sender,
                        address recipient,
                        uint256 amount
                    ) external returns (bool);
                    /**
                     * @dev Emitted when `value` tokens are moved from one account (`from`) to
                     * another (`to`).
                     *
                     * Note that `value` may be zero.
                     */
                    event Transfer(address indexed from, address indexed to, uint256 value);
                    /**
                     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                     * a call to {approve}. `value` is the new allowance.
                     */
                    event Approval(address indexed owner, address indexed spender, uint256 value);
                }
                // SPDX-License-Identifier: MIT
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
                 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
                 *
                 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
                 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
                 * need to send a transaction, and thus is not required to hold Ether at all.
                 */
                interface IERC20Permit {
                    /**
                     * @dev Sets `value` as the allowance of `spender` over `owner`'s tokens,
                     * given `owner`'s signed approval.
                     *
                     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
                     * ordering also apply here.
                     *
                     * Emits an {Approval} event.
                     *
                     * Requirements:
                     *
                     * - `spender` cannot be the zero address.
                     * - `deadline` must be a timestamp in the future.
                     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
                     * over the EIP712-formatted function arguments.
                     * - the signature must use ``owner``'s current nonce (see {nonces}).
                     *
                     * For more information on the signature format, see the
                     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
                     * section].
                     */
                    function permit(
                        address owner,
                        address spender,
                        uint256 value,
                        uint256 deadline,
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) external;
                    /**
                     * @dev Returns the current nonce for `owner`. This value must be
                     * included whenever a signature is generated for {permit}.
                     *
                     * Every successful call to {permit} increases ``owner``'s nonce by one. This
                     * prevents a signature from being used multiple times.
                     */
                    function nonces(address owner) external view returns (uint256);
                    /**
                     * @dev Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.
                     */
                    // solhint-disable-next-line func-name-mixedcase
                    function DOMAIN_SEPARATOR() external view returns (bytes32);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
                 * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
                 * types.
                 *
                 * This concept is unrelated to a Pool's Asset Managers.
                 */
                interface IAsset {
                    // solhint-disable-previous-line no-empty-blocks
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                interface IAuthorizer {
                    /**
                     * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
                     */
                    function canPerform(
                        bytes32 actionId,
                        address account,
                        address where
                    ) external view returns (bool);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./IVault.sol";
                import "./IPoolSwapStructs.sol";
                /**
                 * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
                 * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
                 * either IGeneralPool or IMinimalSwapInfoPool
                 */
                interface IBasePool is IPoolSwapStructs {
                    /**
                     * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
                     * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
                     * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
                     * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
                     *
                     * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
                     *
                     * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
                     * designated to receive any benefits (typically pool shares). `balances` contains the total balances
                     * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                     *
                     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                     * balance.
                     *
                     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                     * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                     *
                     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                     * state-changing operations, such as minting pool shares.
                     */
                    function onJoinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
                    /**
                     * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
                     * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
                     * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
                     * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
                     * `protocolSwapFeePercentage`.
                     *
                     * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
                     *
                     * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
                     * to which the Vault will send the proceeds. `balances` contains the total token balances for each token
                     * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                     *
                     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                     * balance.
                     *
                     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                     * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                     *
                     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                     * state-changing operations, such as burning pool shares.
                     */
                    function onExitPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
                    /**
                     * @dev Returns this Pool's ID, used when interacting with the Vault (to e.g. join the Pool or swap with it).
                     */
                    function getPoolId() external view returns (bytes32);
                    /**
                     * @dev Returns the current swap fee percentage as a 18 decimal fixed point number, so e.g. 1e17 corresponds to a
                     * 10% swap fee.
                     */
                    function getSwapFeePercentage() external view returns (uint256);
                    /**
                     * @dev Returns the scaling factors of each of the Pool's tokens. This is an implementation detail that is typically
                     * not relevant for outside parties, but which might be useful for some types of Pools.
                     */
                    function getScalingFactors() external view returns (uint256[] memory);
                    function queryJoin(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256 bptOut, uint256[] memory amountsIn);
                    function queryExit(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256 bptIn, uint256[] memory amountsOut);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                // Inspired by Aave Protocol's IFlashLoanReceiver.
                import "../solidity-utils/openzeppelin/IERC20.sol";
                interface IFlashLoanRecipient {
                    /**
                     * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
                     *
                     * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
                     * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
                     * Vault, or else the entire flash loan will revert.
                     *
                     * `userData` is the same value passed in the `IVault.flashLoan` call.
                     */
                    function receiveFlashLoan(
                        IERC20[] memory tokens,
                        uint256[] memory amounts,
                        uint256[] memory feeAmounts,
                        bytes memory userData
                    ) external;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./IBasePool.sol";
                /**
                 * @dev Pool contracts with the MinimalSwapInfo or TwoToken specialization settings should implement this interface.
                 *
                 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
                 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will grant
                 * to the pool in a 'given out' swap.
                 *
                 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
                 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
                 * indeed the Vault.
                 */
                interface IMinimalSwapInfoPool is IBasePool {
                    function onSwap(
                        SwapRequest memory swapRequest,
                        uint256 currentBalanceTokenIn,
                        uint256 currentBalanceTokenOut
                    ) external returns (uint256 amount);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "./IVault.sol";
                interface IPoolSwapStructs {
                    // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
                    // IMinimalSwapInfoPool.
                    //
                    // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
                    // 'given out') which indicates whether or not the amount sent by the pool is known.
                    //
                    // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
                    // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
                    //
                    // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
                    // some Pools.
                    //
                    // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
                    // one Pool.
                    //
                    // The meaning of `lastChangeBlock` depends on the Pool specialization:
                    //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
                    //    balance.
                    //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
                    //
                    // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
                    // where the Pool sends the outgoing tokens.
                    //
                    // `userData` is extra data provided by the caller - typically a signature from a trusted party.
                    struct SwapRequest {
                        IVault.SwapKind kind;
                        IERC20 tokenIn;
                        IERC20 tokenOut;
                        uint256 amount;
                        // Misc data
                        bytes32 poolId;
                        uint256 lastChangeBlock;
                        address from;
                        address to;
                        bytes userData;
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "./IVault.sol";
                import "./IAuthorizer.sol";
                interface IProtocolFeesCollector {
                    event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
                    event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
                    function withdrawCollectedFees(
                        IERC20[] calldata tokens,
                        uint256[] calldata amounts,
                        address recipient
                    ) external;
                    function setSwapFeePercentage(uint256 newSwapFeePercentage) external;
                    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external;
                    function getSwapFeePercentage() external view returns (uint256);
                    function getFlashLoanFeePercentage() external view returns (uint256);
                    function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts);
                    function getAuthorizer() external view returns (IAuthorizer);
                    function vault() external view returns (IVault);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "../solidity-utils/helpers/IAuthentication.sol";
                import "../solidity-utils/helpers/ISignaturesValidator.sol";
                import "../solidity-utils/helpers/ITemporarilyPausable.sol";
                import "../solidity-utils/misc/IWETH.sol";
                import "./IAsset.sol";
                import "./IAuthorizer.sol";
                import "./IFlashLoanRecipient.sol";
                import "./IProtocolFeesCollector.sol";
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
                 * don't override one of these declarations.
                 */
                interface IVault is ISignaturesValidator, ITemporarilyPausable, IAuthentication {
                    // Generalities about the Vault:
                    //
                    // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
                    // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
                    // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
                    // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
                    // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
                    //
                    // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
                    // while execution control is transferred to a token contract during a swap) will result in a revert. View
                    // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
                    // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
                    //
                    // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
                    // Authorizer
                    //
                    // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
                    // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
                    // can perform a given action.
                    /**
                     * @dev Returns the Vault's Authorizer.
                     */
                    function getAuthorizer() external view returns (IAuthorizer);
                    /**
                     * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
                     *
                     * Emits an `AuthorizerChanged` event.
                     */
                    function setAuthorizer(IAuthorizer newAuthorizer) external;
                    /**
                     * @dev Emitted when a new authorizer is set by `setAuthorizer`.
                     */
                    event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
                    // Relayers
                    //
                    // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
                    // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
                    // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
                    // this power, two things must occur:
                    //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
                    //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
                    //    functions.
                    //  - Each user must approve the relayer to act on their behalf.
                    // This double protection means users cannot be tricked into approving malicious relayers (because they will not
                    // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
                    // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
                    /**
                     * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
                     */
                    function hasApprovedRelayer(address user, address relayer) external view returns (bool);
                    /**
                     * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
                     *
                     * Emits a `RelayerApprovalChanged` event.
                     */
                    function setRelayerApproval(
                        address sender,
                        address relayer,
                        bool approved
                    ) external;
                    /**
                     * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
                     */
                    event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
                    // Internal Balance
                    //
                    // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
                    // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
                    // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
                    // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
                    //
                    // Internal Balance management features batching, which means a single contract call can be used to perform multiple
                    // operations of different kinds, with different senders and recipients, at once.
                    /**
                     * @dev Returns `user`'s Internal Balance for a set of tokens.
                     */
                    function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
                    /**
                     * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
                     * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
                     * it lets integrators reuse a user's Vault allowance.
                     *
                     * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
                     */
                    function manageUserBalance(UserBalanceOp[] memory ops) external payable;
                    /**
                     * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
                     without manual WETH wrapping or unwrapping.
                     */
                    struct UserBalanceOp {
                        UserBalanceOpKind kind;
                        IAsset asset;
                        uint256 amount;
                        address sender;
                        address payable recipient;
                    }
                    // There are four possible operations in `manageUserBalance`:
                    //
                    // - DEPOSIT_INTERNAL
                    // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
                    // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
                    //
                    // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
                    // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
                    // relevant for relayers).
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - WITHDRAW_INTERNAL
                    // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
                    //
                    // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
                    // it to the recipient as ETH.
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - TRANSFER_INTERNAL
                    // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
                    //
                    // Reverts if the ETH sentinel value is passed.
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - TRANSFER_EXTERNAL
                    // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
                    // relayers, as it lets them reuse a user's Vault allowance.
                    //
                    // Reverts if the ETH sentinel value is passed.
                    //
                    // Emits an `ExternalBalanceTransfer` event.
                    enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
                    /**
                     * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
                     * interacting with Pools using Internal Balance.
                     *
                     * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
                     * address.
                     */
                    event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
                    /**
                     * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
                     */
                    event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
                    // Pools
                    //
                    // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
                    // functionality:
                    //
                    //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
                    // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
                    // which increase with the number of registered tokens.
                    //
                    //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
                    // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
                    // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
                    // independent of the number of registered tokens.
                    //
                    //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
                    // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
                    enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
                    /**
                     * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
                     * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
                     * changed.
                     *
                     * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
                     * depending on the chosen specialization setting. This contract is known as the Pool's contract.
                     *
                     * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
                     * multiple Pools may share the same contract.
                     *
                     * Emits a `PoolRegistered` event.
                     */
                    function registerPool(PoolSpecialization specialization) external returns (bytes32);
                    /**
                     * @dev Emitted when a Pool is registered by calling `registerPool`.
                     */
                    event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
                    /**
                     * @dev Returns a Pool's contract address and specialization setting.
                     */
                    function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
                    /**
                     * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                     *
                     * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
                     * exit by receiving registered tokens, and can only swap registered tokens.
                     *
                     * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
                     * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
                     * ascending order.
                     *
                     * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
                     * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
                     * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
                     * expected to be highly secured smart contracts with sound design principles, and the decision to register an
                     * Asset Manager should not be made lightly.
                     *
                     * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
                     * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
                     * different Asset Manager.
                     *
                     * Emits a `TokensRegistered` event.
                     */
                    function registerTokens(
                        bytes32 poolId,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) external;
                    /**
                     * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
                     */
                    event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
                    /**
                     * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                     *
                     * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
                     * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
                     * must be deregistered in the same `deregisterTokens` call.
                     *
                     * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
                     *
                     * Emits a `TokensDeregistered` event.
                     */
                    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
                    /**
                     * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
                     */
                    event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
                    /**
                     * @dev Returns detailed information for a Pool's registered token.
                     *
                     * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
                     * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
                     * equals the sum of `cash` and `managed`.
                     *
                     * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
                     * `managed` or `total` balance to be greater than 2^112 - 1.
                     *
                     * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
                     * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
                     * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
                     * change for this purpose, and will update `lastChangeBlock`.
                     *
                     * `assetManager` is the Pool's token Asset Manager.
                     */
                    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                        external
                        view
                        returns (
                            uint256 cash,
                            uint256 managed,
                            uint256 lastChangeBlock,
                            address assetManager
                        );
                    /**
                     * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
                     * the tokens' `balances` changed.
                     *
                     * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
                     * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
                     *
                     * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
                     * order as passed to `registerTokens`.
                     *
                     * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
                     * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
                     * instead.
                     */
                    function getPoolTokens(bytes32 poolId)
                        external
                        view
                        returns (
                            IERC20[] memory tokens,
                            uint256[] memory balances,
                            uint256 lastChangeBlock
                        );
                    /**
                     * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
                     * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
                     * Pool shares.
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
                     * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
                     * these maximums.
                     *
                     * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
                     * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
                     * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
                     * back to the caller (not the sender, which is important for relayers).
                     *
                     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                     * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
                     * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
                     * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
                     *
                     * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
                     * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
                     * withdrawn from Internal Balance: attempting to do so will trigger a revert.
                     *
                     * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
                     * their own custom logic. This typically requires additional information from the user (such as the expected number
                     * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
                     * directly to the Pool's contract, as is `recipient`.
                     *
                     * Emits a `PoolBalanceChanged` event.
                     */
                    function joinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        JoinPoolRequest memory request
                    ) external payable;
                    struct JoinPoolRequest {
                        IAsset[] assets;
                        uint256[] maxAmountsIn;
                        bytes userData;
                        bool fromInternalBalance;
                    }
                    /**
                     * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
                     * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
                     * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
                     * `getPoolTokenInfo`).
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
                     * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
                     * it just enforces these minimums.
                     *
                     * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
                     * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
                     * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
                     *
                     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                     * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
                     * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
                     * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
                     *
                     * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
                     * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
                     * do so will trigger a revert.
                     *
                     * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
                     * `tokens` array. This array must match the Pool's registered tokens.
                     *
                     * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
                     * their own custom logic. This typically requires additional information from the user (such as the expected number
                     * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
                     * passed directly to the Pool's contract.
                     *
                     * Emits a `PoolBalanceChanged` event.
                     */
                    function exitPool(
                        bytes32 poolId,
                        address sender,
                        address payable recipient,
                        ExitPoolRequest memory request
                    ) external;
                    struct ExitPoolRequest {
                        IAsset[] assets;
                        uint256[] minAmountsOut;
                        bytes userData;
                        bool toInternalBalance;
                    }
                    /**
                     * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
                     */
                    event PoolBalanceChanged(
                        bytes32 indexed poolId,
                        address indexed liquidityProvider,
                        IERC20[] tokens,
                        int256[] deltas,
                        uint256[] protocolFeeAmounts
                    );
                    enum PoolBalanceChangeKind { JOIN, EXIT }
                    // Swaps
                    //
                    // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
                    // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
                    // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
                    //
                    // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
                    // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
                    // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
                    // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
                    // individual swaps.
                    //
                    // There are two swap kinds:
                    //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
                    // `onSwap` hook) the amount of tokens out (to send to the recipient).
                    //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
                    // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
                    //
                    // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
                    // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
                    // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
                    // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
                    // the final intended token.
                    //
                    // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
                    // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
                    // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
                    // much less gas than they would otherwise.
                    //
                    // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
                    // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
                    // updating the Pool's internal accounting).
                    //
                    // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
                    // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
                    // minimum amount of tokens to receive (by passing a negative value) is specified.
                    //
                    // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
                    // this point in time (e.g. if the transaction failed to be included in a block promptly).
                    //
                    // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
                    // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
                    // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
                    // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
                    //
                    // Finally, Internal Balance can be used when either sending or receiving tokens.
                    enum SwapKind { GIVEN_IN, GIVEN_OUT }
                    /**
                     * @dev Performs a swap with a single Pool.
                     *
                     * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
                     * taken from the Pool, which must be greater than or equal to `limit`.
                     *
                     * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
                     * sent to the Pool, which must be less than or equal to `limit`.
                     *
                     * Internal Balance usage and the recipient are determined by the `funds` struct.
                     *
                     * Emits a `Swap` event.
                     */
                    function swap(
                        SingleSwap memory singleSwap,
                        FundManagement memory funds,
                        uint256 limit,
                        uint256 deadline
                    ) external payable returns (uint256);
                    /**
                     * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
                     * the `kind` value.
                     *
                     * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
                     * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
                     *
                     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                     * used to extend swap behavior.
                     */
                    struct SingleSwap {
                        bytes32 poolId;
                        SwapKind kind;
                        IAsset assetIn;
                        IAsset assetOut;
                        uint256 amount;
                        bytes userData;
                    }
                    /**
                     * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
                     * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
                     *
                     * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
                     * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
                     * the same index in the `assets` array.
                     *
                     * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
                     * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
                     * `amountOut` depending on the swap kind.
                     *
                     * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
                     * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
                     * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
                     *
                     * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
                     * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
                     * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
                     * or unwrapped from WETH by the Vault.
                     *
                     * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
                     * the minimum or maximum amount of each token the vault is allowed to transfer.
                     *
                     * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
                     * equivalent `swap` call.
                     *
                     * Emits `Swap` events.
                     */
                    function batchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds,
                        int256[] memory limits,
                        uint256 deadline
                    ) external payable returns (int256[] memory);
                    /**
                     * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
                     * `assets` array passed to that function, and ETH assets are converted to WETH.
                     *
                     * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
                     * from the previous swap, depending on the swap kind.
                     *
                     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                     * used to extend swap behavior.
                     */
                    struct BatchSwapStep {
                        bytes32 poolId;
                        uint256 assetInIndex;
                        uint256 assetOutIndex;
                        uint256 amount;
                        bytes userData;
                    }
                    /**
                     * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
                     */
                    event Swap(
                        bytes32 indexed poolId,
                        IERC20 indexed tokenIn,
                        IERC20 indexed tokenOut,
                        uint256 amountIn,
                        uint256 amountOut
                    );
                    /**
                     * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
                     * `recipient` account.
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
                     * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
                     * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
                     * `joinPool`.
                     *
                     * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
                     * transferred. This matches the behavior of `exitPool`.
                     *
                     * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
                     * revert.
                     */
                    struct FundManagement {
                        address sender;
                        bool fromInternalBalance;
                        address payable recipient;
                        bool toInternalBalance;
                    }
                    /**
                     * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
                     * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
                     *
                     * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
                     * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
                     * receives are the same that an equivalent `batchSwap` call would receive.
                     *
                     * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
                     * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
                     * approve them for the Vault, or even know a user's address.
                     *
                     * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
                     * eth_call instead of eth_sendTransaction.
                     */
                    function queryBatchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds
                    ) external returns (int256[] memory assetDeltas);
                    // Flash Loans
                    /**
                     * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
                     * and then reverting unless the tokens plus a proportional protocol fee have been returned.
                     *
                     * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
                     * for each token contract. `tokens` must be sorted in ascending order.
                     *
                     * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
                     * `receiveFlashLoan` call.
                     *
                     * Emits `FlashLoan` events.
                     */
                    function flashLoan(
                        IFlashLoanRecipient recipient,
                        IERC20[] memory tokens,
                        uint256[] memory amounts,
                        bytes memory userData
                    ) external;
                    /**
                     * @dev Emitted for each individual flash loan performed by `flashLoan`.
                     */
                    event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
                    // Asset Management
                    //
                    // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
                    // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
                    // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
                    // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
                    // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
                    // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
                    //
                    // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
                    // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
                    //
                    // This concept is unrelated to the IAsset interface.
                    /**
                     * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
                     *
                     * Pool Balance management features batching, which means a single contract call can be used to perform multiple
                     * operations of different kinds, with different Pools and tokens, at once.
                     *
                     * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
                     */
                    function managePoolBalance(PoolBalanceOp[] memory ops) external;
                    struct PoolBalanceOp {
                        PoolBalanceOpKind kind;
                        bytes32 poolId;
                        IERC20 token;
                        uint256 amount;
                    }
                    /**
                     * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
                     *
                     * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
                     *
                     * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
                     * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
                     */
                    enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
                    /**
                     * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
                     */
                    event PoolBalanceManaged(
                        bytes32 indexed poolId,
                        address indexed assetManager,
                        IERC20 indexed token,
                        int256 cashDelta,
                        int256 managedDelta
                    );
                    // Protocol Fees
                    //
                    // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
                    // permissioned accounts.
                    //
                    // There are two kinds of protocol fees:
                    //
                    //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
                    //
                    //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
                    // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
                    // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
                    // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
                    // exiting a Pool in debt without first paying their share.
                    /**
                     * @dev Returns the current protocol fee module.
                     */
                    function getProtocolFeesCollector() external view returns (IProtocolFeesCollector);
                    /**
                     * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
                     * error in some part of the system.
                     *
                     * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
                     *
                     * While the contract is paused, the following features are disabled:
                     * - depositing and transferring internal balance
                     * - transferring external balance (using the Vault's allowance)
                     * - swaps
                     * - joining Pools
                     * - Asset Manager interactions
                     *
                     * Internal Balance can still be withdrawn, and Pools exited.
                     */
                    function setPaused(bool paused) external;
                    /**
                     * @dev Returns the Vault's WETH instance.
                     */
                    function WETH() external view returns (IWETH);
                    // solhint-disable-previous-line func-name-mixedcase
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20Permit.sol";
                /**
                 * @title Highly opinionated token implementation
                 * @author Balancer Labs
                 * @dev
                 * - Includes functions to increase and decrease allowance as a workaround
                 *   for the well-known issue with `approve`:
                 *   https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                 * - Allows for 'infinite allowance', where an allowance of 0xff..ff is not
                 *   decreased by calls to transferFrom
                 * - Lets a token holder use `transferFrom` to send their own tokens,
                 *   without first setting allowance
                 * - Emits 'Approval' events whenever allowance is changed by `transferFrom`
                 * - Assigns infinite allowance for all token holders to the Vault
                 */
                contract BalancerPoolToken is ERC20Permit {
                    IVault private immutable _vault;
                    constructor(
                        string memory tokenName,
                        string memory tokenSymbol,
                        IVault vault
                    ) ERC20(tokenName, tokenSymbol) ERC20Permit(tokenName) {
                        _vault = vault;
                    }
                    function getVault() public view returns (IVault) {
                        return _vault;
                    }
                    // Overrides
                    /**
                     * @dev Override to grant the Vault infinite allowance, causing for Pool Tokens to not require approval.
                     *
                     * This is sound as the Vault already provides authorization mechanisms when initiation token transfers, which this
                     * contract inherits.
                     */
                    function allowance(address owner, address spender) public view override returns (uint256) {
                        if (spender == address(getVault())) {
                            return uint256(-1);
                        } else {
                            return super.allowance(owner, spender);
                        }
                    }
                    /**
                     * @dev Override to allow for 'infinite allowance' and let the token owner use `transferFrom` with no self-allowance
                     */
                    function transferFrom(
                        address sender,
                        address recipient,
                        uint256 amount
                    ) public override returns (bool) {
                        uint256 currentAllowance = allowance(sender, msg.sender);
                        _require(msg.sender == sender || currentAllowance >= amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE);
                        _transfer(sender, recipient, amount);
                        if (msg.sender != sender && currentAllowance != uint256(-1)) {
                            // Because of the previous require, we know that if msg.sender != sender then currentAllowance >= amount
                            _approve(sender, msg.sender, currentAllowance - amount);
                        }
                        return true;
                    }
                    /**
                     * @dev Override to allow decreasing allowance by more than the current amount (setting it to zero)
                     */
                    function decreaseAllowance(address spender, uint256 amount) public override returns (bool) {
                        uint256 currentAllowance = allowance(msg.sender, spender);
                        if (amount >= currentAllowance) {
                            _approve(msg.sender, spender, 0);
                        } else {
                            // No risk of underflow due to if condition
                            _approve(msg.sender, spender, currentAllowance - amount);
                        }
                        return true;
                    }
                    // Internal functions
                    function _mintPoolTokens(address recipient, uint256 amount) internal {
                        _mint(recipient, amount);
                    }
                    function _burnPoolTokens(address sender, uint256 amount) internal {
                        _burn(sender, amount);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/pool-utils/IControlledPool.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IBasePool.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/ScalingHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/TemporarilyPausable.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "./lib/PoolRegistrationLib.sol";
                import "./BalancerPoolToken.sol";
                import "./BasePoolAuthorization.sol";
                import "./RecoveryMode.sol";
                // solhint-disable max-states-count
                /**
                 * @notice Reference implementation for the base layer of a Pool contract.
                 * @dev Reference implementation for the base layer of a Pool contract that manages a single Pool with optional
                 * Asset Managers, an admin-controlled swap fee percentage, and an emergency pause mechanism.
                 *
                 * This Pool pays protocol fees by minting BPT directly to the ProtocolFeeCollector instead of using the
                 * `dueProtocolFees` return value. This results in the underlying tokens continuing to provide liquidity
                 * for traders, while still keeping gas usage to a minimum since only a single token (the BPT) is transferred.
                 *
                 * Note that neither swap fees nor the pause mechanism are used by this contract. They are passed through so that
                 * derived contracts can use them via the `_addSwapFeeAmount` and `_subtractSwapFeeAmount` functions, and the
                 * `whenNotPaused` modifier.
                 *
                 * No admin permissions are checked here: instead, this contract delegates that to the Vault's own Authorizer.
                 *
                 * Because this contract doesn't implement the swap hooks, derived contracts should generally inherit from
                 * BaseGeneralPool or BaseMinimalSwapInfoPool. Otherwise, subclasses must inherit from the corresponding interfaces
                 * and implement the swap callbacks themselves.
                 */
                abstract contract BasePool is
                    IBasePool,
                    IControlledPool,
                    BasePoolAuthorization,
                    BalancerPoolToken,
                    TemporarilyPausable,
                    RecoveryMode
                {
                    using WordCodec for bytes32;
                    using FixedPoint for uint256;
                    using BasePoolUserData for bytes;
                    uint256 private constant _MIN_TOKENS = 2;
                    uint256 private constant _DEFAULT_MINIMUM_BPT = 1e6;
                    // 1e18 corresponds to 1.0, or a 100% fee
                    uint256 private constant _MIN_SWAP_FEE_PERCENTAGE = 1e12; // 0.0001%
                    uint256 private constant _MAX_SWAP_FEE_PERCENTAGE = 1e17; // 10% - this fits in 64 bits
                    // `_miscData` is a storage slot that can be used to store unrelated pieces of information. All pools store the
                    // recovery mode flag and swap fee percentage, but `miscData` can be extended to store more pieces of information.
                    // The most signficant bit is reserved for the recovery mode flag, and the swap fee percentage is stored in
                    // the next most significant 63 bits, leaving the remaining 192 bits free to store any other information derived
                    // pools might need.
                    //
                    // This slot is preferred for gas-sensitive operations as it is read in all joins, swaps and exits,
                    // and therefore warm.
                    // [ recovery | swap  fee | available ]
                    // [   1 bit  |  63 bits  |  192 bits ]
                    // [ MSB                          LSB ]
                    bytes32 private _miscData;
                    uint256 private constant _SWAP_FEE_PERCENTAGE_OFFSET = 192;
                    uint256 private constant _RECOVERY_MODE_BIT_OFFSET = 255;
                    // A fee can never be larger than FixedPoint.ONE, which fits in 60 bits, so 63 is more than enough.
                    uint256 private constant _SWAP_FEE_PERCENTAGE_BIT_LENGTH = 63;
                    bytes32 private immutable _poolId;
                    // Note that this value is immutable in the Vault, so we can make it immutable here and save gas
                    IProtocolFeesCollector private immutable _protocolFeesCollector;
                    event SwapFeePercentageChanged(uint256 swapFeePercentage);
                    constructor(
                        IVault vault,
                        IVault.PoolSpecialization specialization,
                        string memory name,
                        string memory symbol,
                        IERC20[] memory tokens,
                        address[] memory assetManagers,
                        uint256 swapFeePercentage,
                        uint256 pauseWindowDuration,
                        uint256 bufferPeriodDuration,
                        address owner
                    )
                        // Base Pools are expected to be deployed using factories. By using the factory address as the action
                        // disambiguator, we make all Pools deployed by the same factory share action identifiers. This allows for
                        // simpler management of permissions (such as being able to manage granting the 'set fee percentage' action in
                        // any Pool created by the same factory), while still making action identifiers unique among different factories
                        // if the selectors match, preventing accidental errors.
                        Authentication(bytes32(uint256(msg.sender)))
                        BalancerPoolToken(name, symbol, vault)
                        BasePoolAuthorization(owner)
                        TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration)
                        RecoveryMode(vault)
                    {
                        _require(tokens.length >= _MIN_TOKENS, Errors.MIN_TOKENS);
                        _require(tokens.length <= _getMaxTokens(), Errors.MAX_TOKENS);
                        _setSwapFeePercentage(swapFeePercentage);
                        bytes32 poolId = PoolRegistrationLib.registerPoolWithAssetManagers(
                            vault,
                            specialization,
                            tokens,
                            assetManagers
                        );
                        // Set immutable state variables - these cannot be read from during construction
                        _poolId = poolId;
                        _protocolFeesCollector = vault.getProtocolFeesCollector();
                    }
                    // Getters / Setters
                    /**
                     * @notice Return the pool id.
                     */
                    function getPoolId() public view override returns (bytes32) {
                        return _poolId;
                    }
                    function _getTotalTokens() internal view virtual returns (uint256);
                    function _getMaxTokens() internal pure virtual returns (uint256);
                    /**
                     * @dev Returns the minimum BPT supply. This amount is minted to the zero address during initialization, effectively
                     * locking it.
                     *
                     * This is useful to make sure Pool initialization happens only once, but derived Pools can change this value (even
                     * to zero) by overriding this function.
                     */
                    function _getMinimumBpt() internal pure virtual returns (uint256) {
                        return _DEFAULT_MINIMUM_BPT;
                    }
                    /**
                     * @notice Return the current value of the swap fee percentage.
                     * @dev This is stored in `_miscData`.
                     */
                    function getSwapFeePercentage() public view virtual override returns (uint256) {
                        return _miscData.decodeUint(_SWAP_FEE_PERCENTAGE_OFFSET, _SWAP_FEE_PERCENTAGE_BIT_LENGTH);
                    }
                    /**
                     * @notice Return the ProtocolFeesCollector contract.
                     * @dev This is immutable, and retrieved from the Vault on construction. (It is also immutable in the Vault.)
                     */
                    function getProtocolFeesCollector() public view returns (IProtocolFeesCollector) {
                        return _protocolFeesCollector;
                    }
                    /**
                     * @notice Set the swap fee percentage.
                     * @dev This is a permissioned function, and disabled if the pool is paused. The swap fee must be within the
                     * bounds set by MIN_SWAP_FEE_PERCENTAGE/MAX_SWAP_FEE_PERCENTAGE. Emits the SwapFeePercentageChanged event.
                     */
                    function setSwapFeePercentage(uint256 swapFeePercentage) public virtual override authenticate whenNotPaused {
                        _setSwapFeePercentage(swapFeePercentage);
                    }
                    function _setSwapFeePercentage(uint256 swapFeePercentage) internal virtual {
                        _require(swapFeePercentage >= _getMinSwapFeePercentage(), Errors.MIN_SWAP_FEE_PERCENTAGE);
                        _require(swapFeePercentage <= _getMaxSwapFeePercentage(), Errors.MAX_SWAP_FEE_PERCENTAGE);
                        _miscData = _miscData.insertUint(
                            swapFeePercentage,
                            _SWAP_FEE_PERCENTAGE_OFFSET,
                            _SWAP_FEE_PERCENTAGE_BIT_LENGTH
                        );
                        emit SwapFeePercentageChanged(swapFeePercentage);
                    }
                    function _getMinSwapFeePercentage() internal pure virtual returns (uint256) {
                        return _MIN_SWAP_FEE_PERCENTAGE;
                    }
                    function _getMaxSwapFeePercentage() internal pure virtual returns (uint256) {
                        return _MAX_SWAP_FEE_PERCENTAGE;
                    }
                    /**
                     * @notice Returns whether the pool is in Recovery Mode.
                     */
                    function inRecoveryMode() public view override returns (bool) {
                        return _miscData.decodeBool(_RECOVERY_MODE_BIT_OFFSET);
                    }
                    /**
                     * @dev Sets the recoveryMode state, and emits the corresponding event.
                     */
                    function _setRecoveryMode(bool enabled) internal virtual override {
                        _miscData = _miscData.insertBool(enabled, _RECOVERY_MODE_BIT_OFFSET);
                        emit RecoveryModeStateChanged(enabled);
                        // Some pools need to update their state when leaving recovery mode to ensure proper functioning of the Pool.
                        // We do not allow an `_onEnableRecoveryMode()` hook as this may jeopardize the ability to enable Recovery mode.
                        if (!enabled) _onDisableRecoveryMode();
                    }
                    /**
                     * @dev Performs any necessary actions on the disabling of Recovery Mode.
                     * This is usually to reset any fee collection mechanisms to ensure that they operate correctly going forward.
                     */
                    function _onDisableRecoveryMode() internal virtual {
                        // solhint-disable-previous-line no-empty-blocks
                    }
                    /**
                     * @notice Pause the pool: an emergency action which disables all pool functions.
                     * @dev This is a permissioned function that will only work during the Pause Window set during pool factory
                     * deployment (see `TemporarilyPausable`).
                     */
                    function pause() external authenticate {
                        _setPaused(true);
                    }
                    /**
                     * @notice Reverse a `pause` operation, and restore a pool to normal functionality.
                     * @dev This is a permissioned function that will only work on a paused pool within the Buffer Period set during
                     * pool factory deployment (see `TemporarilyPausable`). Note that any paused pools will automatically unpause
                     * after the Buffer Period expires.
                     */
                    function unpause() external authenticate {
                        _setPaused(false);
                    }
                    function _isOwnerOnlyAction(bytes32 actionId) internal view virtual override returns (bool) {
                        return (actionId == getActionId(this.setSwapFeePercentage.selector)) || super._isOwnerOnlyAction(actionId);
                    }
                    function _getMiscData() internal view returns (bytes32) {
                        return _miscData;
                    }
                    /**
                     * @dev Inserts data into the least-significant 192 bits of the misc data storage slot.
                     * Note that the remaining 64 bits are used for the swap fee percentage and cannot be overloaded.
                     */
                    function _setMiscData(bytes32 newData) internal {
                        _miscData = _miscData.insertBits192(newData, 0);
                    }
                    // Join / Exit Hooks
                    modifier onlyVault(bytes32 poolId) {
                        _require(msg.sender == address(getVault()), Errors.CALLER_NOT_VAULT);
                        _require(poolId == getPoolId(), Errors.INVALID_POOL_ID);
                        _;
                    }
                    /**
                     * @notice Vault hook for adding liquidity to a pool (including the first time, "initializing" the pool).
                     * @dev This function can only be called from the Vault, from `joinPool`.
                     */
                    function onJoinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
                        _beforeSwapJoinExit();
                        uint256[] memory scalingFactors = _scalingFactors();
                        if (totalSupply() == 0) {
                            (uint256 bptAmountOut, uint256[] memory amountsIn) = _onInitializePool(
                                poolId,
                                sender,
                                recipient,
                                scalingFactors,
                                userData
                            );
                            // On initialization, we lock _getMinimumBpt() by minting it for the zero address. This BPT acts as a
                            // minimum as it will never be burned, which reduces potential issues with rounding, and also prevents the
                            // Pool from ever being fully drained.
                            _require(bptAmountOut >= _getMinimumBpt(), Errors.MINIMUM_BPT);
                            _mintPoolTokens(address(0), _getMinimumBpt());
                            _mintPoolTokens(recipient, bptAmountOut - _getMinimumBpt());
                            // amountsIn are amounts entering the Pool, so we round up.
                            _downscaleUpArray(amountsIn, scalingFactors);
                            return (amountsIn, new uint256[](balances.length));
                        } else {
                            _upscaleArray(balances, scalingFactors);
                            (uint256 bptAmountOut, uint256[] memory amountsIn) = _onJoinPool(
                                poolId,
                                sender,
                                recipient,
                                balances,
                                lastChangeBlock,
                                inRecoveryMode() ? 0 : protocolSwapFeePercentage, // Protocol fees are disabled while in recovery mode
                                scalingFactors,
                                userData
                            );
                            // Note we no longer use `balances` after calling `_onJoinPool`, which may mutate it.
                            _mintPoolTokens(recipient, bptAmountOut);
                            // amountsIn are amounts entering the Pool, so we round up.
                            _downscaleUpArray(amountsIn, scalingFactors);
                            // This Pool ignores the `dueProtocolFees` return value, so we simply return a zeroed-out array.
                            return (amountsIn, new uint256[](balances.length));
                        }
                    }
                    /**
                     * @notice Vault hook for removing liquidity from a pool.
                     * @dev This function can only be called from the Vault, from `exitPool`.
                     */
                    function onExitPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
                        uint256[] memory amountsOut;
                        uint256 bptAmountIn;
                        // When a user calls `exitPool`, this is the first point of entry from the Vault.
                        // We first check whether this is a Recovery Mode exit - if so, we proceed using this special lightweight exit
                        // mechanism which avoids computing any complex values, interacting with external contracts, etc., and generally
                        // should always work, even if the Pool's mathematics or a dependency break down.
                        if (userData.isRecoveryModeExitKind()) {
                            // This exit kind is only available in Recovery Mode.
                            _ensureInRecoveryMode();
                            // Note that we don't upscale balances nor downscale amountsOut - we don't care about scaling factors during
                            // a recovery mode exit.
                            (bptAmountIn, amountsOut) = _doRecoveryModeExit(balances, totalSupply(), userData);
                        } else {
                            // Note that we only call this if we're not in a recovery mode exit.
                            _beforeSwapJoinExit();
                            uint256[] memory scalingFactors = _scalingFactors();
                            _upscaleArray(balances, scalingFactors);
                            (bptAmountIn, amountsOut) = _onExitPool(
                                poolId,
                                sender,
                                recipient,
                                balances,
                                lastChangeBlock,
                                inRecoveryMode() ? 0 : protocolSwapFeePercentage, // Protocol fees are disabled while in recovery mode
                                scalingFactors,
                                userData
                            );
                            // amountsOut are amounts exiting the Pool, so we round down.
                            _downscaleDownArray(amountsOut, scalingFactors);
                        }
                        // Note we no longer use `balances` after calling `_onExitPool`, which may mutate it.
                        _burnPoolTokens(sender, bptAmountIn);
                        // This Pool ignores the `dueProtocolFees` return value, so we simply return a zeroed-out array.
                        return (amountsOut, new uint256[](balances.length));
                    }
                    // Query functions
                    /**
                     * @notice "Dry run" `onJoinPool`.
                     * @dev Returns the amount of BPT that would be granted to `recipient` if the `onJoinPool` hook were called by the
                     * Vault with the same arguments, along with the number of tokens `sender` would have to supply.
                     *
                     * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
                     * data, such as the protocol swap fee percentage and Pool balances.
                     *
                     * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
                     * explicitly use eth_call instead of eth_sendTransaction.
                     */
                    function queryJoin(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external override returns (uint256 bptOut, uint256[] memory amountsIn) {
                        InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
                        _queryAction(
                            poolId,
                            sender,
                            recipient,
                            balances,
                            lastChangeBlock,
                            protocolSwapFeePercentage,
                            userData,
                            _onJoinPool,
                            _downscaleUpArray
                        );
                        // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
                        // and we don't need to return anything here - it just silences compiler warnings.
                        return (bptOut, amountsIn);
                    }
                    /**
                     * @notice "Dry run" `onExitPool`.
                     * @dev Returns the amount of BPT that would be burned from `sender` if the `onExitPool` hook were called by the
                     * Vault with the same arguments, along with the number of tokens `recipient` would receive.
                     *
                     * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
                     * data, such as the protocol swap fee percentage and Pool balances.
                     *
                     * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
                     * explicitly use eth_call instead of eth_sendTransaction.
                     */
                    function queryExit(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external override returns (uint256 bptIn, uint256[] memory amountsOut) {
                        InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
                        _queryAction(
                            poolId,
                            sender,
                            recipient,
                            balances,
                            lastChangeBlock,
                            protocolSwapFeePercentage,
                            userData,
                            _onExitPool,
                            _downscaleDownArray
                        );
                        // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
                        // and we don't need to return anything here - it just silences compiler warnings.
                        return (bptIn, amountsOut);
                    }
                    // Internal hooks to be overridden by derived contracts - all token amounts (except BPT) in these interfaces are
                    // upscaled.
                    /**
                     * @dev Called when the Pool is joined for the first time; that is, when the BPT total supply is zero.
                     *
                     * Returns the amount of BPT to mint, and the token amounts the Pool will receive in return.
                     *
                     * Minted BPT will be sent to `recipient`, except for _getMinimumBpt(), which will be deducted from this amount and
                     * sent to the zero address instead. This will cause that BPT to remain forever locked there, preventing total BTP
                     * from ever dropping below that value, and ensuring `_onInitializePool` can only be called once in the entire
                     * Pool's lifetime.
                     *
                     * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
                     * be downscaled (rounding up) before being returned to the Vault.
                     */
                    function _onInitializePool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory scalingFactors,
                        bytes memory userData
                    ) internal virtual returns (uint256 bptAmountOut, uint256[] memory amountsIn);
                    /**
                     * @dev Called whenever the Pool is joined after the first initialization join (see `_onInitializePool`).
                     *
                     * Returns the amount of BPT to mint, the token amounts that the Pool will receive in return, and the number of
                     * tokens to pay in protocol swap fees.
                     *
                     * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
                     * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
                     *
                     * Minted BPT will be sent to `recipient`.
                     *
                     * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
                     * be downscaled (rounding up) before being returned to the Vault.
                     *
                     * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onJoinPool`). These
                     * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
                     */
                    function _onJoinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        uint256[] memory scalingFactors,
                        bytes memory userData
                    ) internal virtual returns (uint256 bptAmountOut, uint256[] memory amountsIn);
                    /**
                     * @dev Called whenever the Pool is exited.
                     *
                     * Returns the amount of BPT to burn, the token amounts for each Pool token that the Pool will grant in return, and
                     * the number of tokens to pay in protocol swap fees.
                     *
                     * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
                     * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
                     *
                     * BPT will be burnt from `sender`.
                     *
                     * The Pool will grant tokens to `recipient`. These amounts are considered upscaled and will be downscaled
                     * (rounding down) before being returned to the Vault.
                     *
                     * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onExitPool`). These
                     * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
                     */
                    function _onExitPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        uint256[] memory scalingFactors,
                        bytes memory userData
                    ) internal virtual returns (uint256 bptAmountIn, uint256[] memory amountsOut);
                    /**
                     * @dev Called at the very beginning of swaps, joins and exits, even before the scaling factors are read. Derived
                     * contracts can extend this implementation to perform any state-changing operations they might need (including e.g.
                     * updating the scaling factors),
                     *
                     * The only scenario in which this function is not called is during a recovery mode exit. This makes it safe to
                     * perform non-trivial computations or interact with external dependencies here, as recovery mode will not be
                     * affected.
                     *
                     * Since this contract does not implement swaps, derived contracts must also make sure this function is called on
                     * swap handlers.
                     */
                    function _beforeSwapJoinExit() internal virtual {
                        // All joins, exits and swaps are disabled (except recovery mode exits).
                        _ensureNotPaused();
                    }
                    // Internal functions
                    /**
                     * @dev Pays protocol fees by minting `bptAmount` to the Protocol Fee Collector.
                     */
                    function _payProtocolFees(uint256 bptAmount) internal {
                        if (bptAmount > 0) {
                            _mintPoolTokens(address(getProtocolFeesCollector()), bptAmount);
                        }
                    }
                    /**
                     * @dev Adds swap fee amount to `amount`, returning a higher value.
                     */
                    function _addSwapFeeAmount(uint256 amount) internal view returns (uint256) {
                        // This returns amount + fee amount, so we round up (favoring a higher fee amount).
                        return amount.divUp(getSwapFeePercentage().complement());
                    }
                    /**
                     * @dev Subtracts swap fee amount from `amount`, returning a lower value.
                     */
                    function _subtractSwapFeeAmount(uint256 amount) internal view returns (uint256) {
                        // This returns amount - fee amount, so we round up (favoring a higher fee amount).
                        uint256 feeAmount = amount.mulUp(getSwapFeePercentage());
                        return amount.sub(feeAmount);
                    }
                    // Scaling
                    /**
                     * @dev Returns a scaling factor that, when multiplied to a token amount for `token`, normalizes its balance as if
                     * it had 18 decimals.
                     */
                    function _computeScalingFactor(IERC20 token) internal view returns (uint256) {
                        if (address(token) == address(this)) {
                            return FixedPoint.ONE;
                        }
                        // Tokens that don't implement the `decimals` method are not supported.
                        uint256 tokenDecimals = ERC20(address(token)).decimals();
                        // Tokens with more than 18 decimals are not supported.
                        uint256 decimalsDifference = Math.sub(18, tokenDecimals);
                        return FixedPoint.ONE * 10**decimalsDifference;
                    }
                    /**
                     * @dev Returns the scaling factor for one of the Pool's tokens. Reverts if `token` is not a token registered by the
                     * Pool.
                     *
                     * All scaling factors are fixed-point values with 18 decimals, to allow for this function to be overridden by
                     * derived contracts that need to apply further scaling, making these factors potentially non-integer.
                     *
                     * The largest 'base' scaling factor (i.e. in tokens with less than 18 decimals) is 10**18, which in fixed-point is
                     * 10**36. This value can be multiplied with a 112 bit Vault balance with no overflow by a factor of ~1e7, making
                     * even relatively 'large' factors safe to use.
                     *
                     * The 1e7 figure is the result of 2**256 / (1e18 * 1e18 * 2**112).
                     */
                    function _scalingFactor(IERC20 token) internal view virtual returns (uint256);
                    /**
                     * @dev Same as `_scalingFactor()`, except for all registered tokens (in the same order as registered). The Vault
                     * will always pass balances in this order when calling any of the Pool hooks.
                     */
                    function _scalingFactors() internal view virtual returns (uint256[] memory);
                    function getScalingFactors() external view override returns (uint256[] memory) {
                        return _scalingFactors();
                    }
                    function _getAuthorizer() internal view override returns (IAuthorizer) {
                        // Access control management is delegated to the Vault's Authorizer. This lets Balancer Governance manage which
                        // accounts can call permissioned functions: for example, to perform emergency pauses.
                        // If the owner is delegated, then *all* permissioned functions, including `setSwapFeePercentage`, will be under
                        // Governance control.
                        return getVault().getAuthorizer();
                    }
                    function _queryAction(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData,
                        function(bytes32, address, address, uint256[] memory, uint256, uint256, uint256[] memory, bytes memory)
                            internal
                            returns (uint256, uint256[] memory) _action,
                        function(uint256[] memory, uint256[] memory) internal view _downscaleArray
                    ) private {
                        // This uses the same technique used by the Vault in queryBatchSwap. Refer to that function for a detailed
                        // explanation.
                        if (msg.sender != address(this)) {
                            // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
                            // the preceding if statement will be executed instead.
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, ) = address(this).call(msg.data);
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                // This call should always revert to decode the bpt and token amounts from the revert reason
                                switch success
                                    case 0 {
                                        // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                                        // stored there as we take full control of the execution and then immediately return.
                                        // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                                        // there was another revert reason and we should forward it.
                                        returndatacopy(0, 0, 0x04)
                                        let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                                        // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                                        if eq(eq(error, 0x43adbafb00000000000000000000000000000000000000000000000000000000), 0) {
                                            returndatacopy(0, 0, returndatasize())
                                            revert(0, returndatasize())
                                        }
                                        // The returndata contains the signature, followed by the raw memory representation of the
                                        // `bptAmount` and `tokenAmounts` (array: length + data). We need to return an ABI-encoded
                                        // representation of these.
                                        // An ABI-encoded response will include one additional field to indicate the starting offset of
                                        // the `tokenAmounts` array. The `bptAmount` will be laid out in the first word of the
                                        // returndata.
                                        //
                                        // In returndata:
                                        // [ signature ][ bptAmount ][ tokenAmounts length ][ tokenAmounts values ]
                                        // [  4 bytes  ][  32 bytes ][       32 bytes      ][ (32 * length) bytes ]
                                        //
                                        // We now need to return (ABI-encoded values):
                                        // [ bptAmount ][ tokeAmounts offset ][ tokenAmounts length ][ tokenAmounts values ]
                                        // [  32 bytes ][       32 bytes     ][       32 bytes      ][ (32 * length) bytes ]
                                        // We copy 32 bytes for the `bptAmount` from returndata into memory.
                                        // Note that we skip the first 4 bytes for the error signature
                                        returndatacopy(0, 0x04, 32)
                                        // The offsets are 32-bytes long, so the array of `tokenAmounts` will start after
                                        // the initial 64 bytes.
                                        mstore(0x20, 64)
                                        // We now copy the raw memory array for the `tokenAmounts` from returndata into memory.
                                        // Since bpt amount and offset take up 64 bytes, we start copying at address 0x40. We also
                                        // skip the first 36 bytes from returndata, which correspond to the signature plus bpt amount.
                                        returndatacopy(0x40, 0x24, sub(returndatasize(), 36))
                                        // We finally return the ABI-encoded uint256 and the array, which has a total length equal to
                                        // the size of returndata, plus the 32 bytes of the offset but without the 4 bytes of the
                                        // error signature.
                                        return(0, add(returndatasize(), 28))
                                    }
                                    default {
                                        // This call should always revert, but we fail nonetheless if that didn't happen
                                        invalid()
                                    }
                            }
                        } else {
                            // This imitates the relevant parts of the bodies of onJoin and onExit. Since they're not virtual, we know
                            // that their implementations will match this regardless of what derived contracts might do.
                            _beforeSwapJoinExit();
                            uint256[] memory scalingFactors = _scalingFactors();
                            _upscaleArray(balances, scalingFactors);
                            (uint256 bptAmount, uint256[] memory tokenAmounts) = _action(
                                poolId,
                                sender,
                                recipient,
                                balances,
                                lastChangeBlock,
                                protocolSwapFeePercentage,
                                scalingFactors,
                                userData
                            );
                            _downscaleArray(tokenAmounts, scalingFactors);
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                // We will return a raw representation of `bptAmount` and `tokenAmounts` in memory, which is composed of
                                // a 32-byte uint256, followed by a 32-byte for the array length, and finally the 32-byte uint256 values
                                // Because revert expects a size in bytes, we multiply the array length (stored at `tokenAmounts`) by 32
                                let size := mul(mload(tokenAmounts), 32)
                                // We store the `bptAmount` in the previous slot to the `tokenAmounts` array. We can make sure there
                                // will be at least one available slot due to how the memory scratch space works.
                                // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                                let start := sub(tokenAmounts, 0x20)
                                mstore(start, bptAmount)
                                // We send one extra value for the error signature "QueryError(uint256,uint256[])" which is 0x43adbafb
                                // We use the previous slot to `bptAmount`.
                                mstore(sub(start, 0x20), 0x0000000000000000000000000000000000000000000000000000000043adbafb)
                                start := sub(start, 0x04)
                                // When copying from `tokenAmounts` into returndata, we copy the additional 68 bytes to also return
                                // the `bptAmount`, the array 's length, and the error signature.
                                revert(start, add(size, 68))
                            }
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/Authentication.sol";
                /**
                 * @dev Base authorization layer implementation for Pools.
                 *
                 * The owner account can call some of the permissioned functions - access control of the rest is delegated to the
                 * Authorizer. Note that this owner is immutable: more sophisticated permission schemes, such as multiple ownership,
                 * granular roles, etc., could be built on top of this by making the owner a smart contract.
                 *
                 * Access control of all other permissioned functions is delegated to an Authorizer. It is also possible to delegate
                 * control of *all* permissioned functions to the Authorizer by setting the owner address to `_DELEGATE_OWNER`.
                 */
                abstract contract BasePoolAuthorization is Authentication {
                    address private immutable _owner;
                    address internal constant _DELEGATE_OWNER = 0xBA1BA1ba1BA1bA1bA1Ba1BA1ba1BA1bA1ba1ba1B;
                    constructor(address owner) {
                        _owner = owner;
                    }
                    function getOwner() public view returns (address) {
                        return _owner;
                    }
                    function getAuthorizer() external view returns (IAuthorizer) {
                        return _getAuthorizer();
                    }
                    function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
                        if ((getOwner() != _DELEGATE_OWNER) && _isOwnerOnlyAction(actionId)) {
                            // Only the owner can perform "owner only" actions, unless the owner is delegated.
                            return msg.sender == getOwner();
                        } else {
                            // Non-owner actions are always processed via the Authorizer, as "owner only" ones are when delegated.
                            return _getAuthorizer().canPerform(actionId, account, address(this));
                        }
                    }
                    function _isOwnerOnlyAction(bytes32) internal view virtual returns (bool) {
                        return false;
                    }
                    function _getAuthorizer() internal view virtual returns (IAuthorizer);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                library BasePoolMath {
                    using FixedPoint for uint256;
                    function computeProportionalAmountsIn(
                        uint256[] memory balances,
                        uint256 bptTotalSupply,
                        uint256 bptAmountOut
                    ) internal pure returns (uint256[] memory amountsIn) {
                        /************************************************************************************
                        // computeProportionalAmountsIn                                                    //
                        // (per token)                                                                     //
                        // aI = amountIn                   /      bptOut      \\                            //
                        // b = balance           aI = b * | ----------------- |                            //
                        // bptOut = bptAmountOut           \\  bptTotalSupply  /                            //
                        // bpt = bptTotalSupply                                                            //
                        ************************************************************************************/
                        // Since we're computing amounts in, we round up overall. This means rounding up on both the
                        // multiplication and division.
                        uint256 bptRatio = bptAmountOut.divUp(bptTotalSupply);
                        amountsIn = new uint256[](balances.length);
                        for (uint256 i = 0; i < balances.length; i++) {
                            amountsIn[i] = balances[i].mulUp(bptRatio);
                        }
                    }
                    function computeProportionalAmountsOut(
                        uint256[] memory balances,
                        uint256 bptTotalSupply,
                        uint256 bptAmountIn
                    ) internal pure returns (uint256[] memory amountsOut) {
                        /**********************************************************************************************
                        // computeProportionalAmountsOut                                                             //
                        // (per token)                                                                               //
                        // aO = tokenAmountOut             /        bptIn         \\                                  //
                        // b = tokenBalance      a0 = b * | ---------------------  |                                 //
                        // bptIn = bptAmountIn             \\     bptTotalSupply    /                                 //
                        // bpt = bptTotalSupply                                                                      //
                        **********************************************************************************************/
                        // Since we're computing an amount out, we round down overall. This means rounding down on both the
                        // multiplication and division.
                        uint256 bptRatio = bptAmountIn.divDown(bptTotalSupply);
                        amountsOut = new uint256[](balances.length);
                        for (uint256 i = 0; i < balances.length; i++) {
                            amountsOut[i] = balances[i].mulDown(bptRatio);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                library PoolRegistrationLib {
                    function registerPool(
                        IVault vault,
                        IVault.PoolSpecialization specialization,
                        IERC20[] memory tokens
                    ) internal returns (bytes32) {
                        return registerPoolWithAssetManagers(vault, specialization, tokens, new address[](tokens.length));
                    }
                    function registerPoolWithAssetManagers(
                        IVault vault,
                        IVault.PoolSpecialization specialization,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) internal returns (bytes32) {
                        // The Vault only requires the token list to be ordered for the Two Token Pools specialization. However,
                        // to make the developer experience consistent, we are requiring this condition for all the native pools.
                        //
                        // Note that for Pools which can register and deregister tokens after deployment, this property may not hold
                        // as tokens which are added to the Pool after deployment are always added to the end of the array.
                        InputHelpers.ensureArrayIsSorted(tokens);
                        return _registerPool(vault, specialization, tokens, assetManagers);
                    }
                    function registerComposablePool(
                        IVault vault,
                        IVault.PoolSpecialization specialization,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) internal returns (bytes32) {
                        // The Vault only requires the token list to be ordered for the Two Token Pools specialization. However,
                        // to make the developer experience consistent, we are requiring this condition for all the native pools.
                        //
                        // Note that for Pools which can register and deregister tokens after deployment, this property may not hold
                        // as tokens which are added to the Pool after deployment are always added to the end of the array.
                        InputHelpers.ensureArrayIsSorted(tokens);
                        IERC20[] memory composableTokens = new IERC20[](tokens.length + 1);
                        // We insert the Pool's BPT address into the first position.
                        // This allows us to know the position of the BPT token in the tokens array without explicitly tracking it.
                        // When deregistering a token, the token at the end of the array is moved into the index of the deregistered
                        // token, changing its index. By placing BPT at the beginning of the tokens array we can be sure that its index
                        // will never change unless it is deregistered itself (something which composable pools must prevent anyway).
                        composableTokens[0] = IERC20(address(this));
                        for (uint256 i = 0; i < tokens.length; i++) {
                            composableTokens[i + 1] = tokens[i];
                        }
                        address[] memory composableAssetManagers = new address[](assetManagers.length + 1);
                        // We do not allow an asset manager for the Pool's BPT.
                        composableAssetManagers[0] = address(0);
                        for (uint256 i = 0; i < assetManagers.length; i++) {
                            composableAssetManagers[i + 1] = assetManagers[i];
                        }
                        return _registerPool(vault, specialization, composableTokens, composableAssetManagers);
                    }
                    function _registerPool(
                        IVault vault,
                        IVault.PoolSpecialization specialization,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) private returns (bytes32) {
                        bytes32 poolId = vault.registerPool(specialization);
                        // We don't need to check that tokens and assetManagers have the same length, since the Vault already performs
                        // that check.
                        vault.registerTokens(poolId, tokens, assetManagers);
                        return poolId;
                    }
                    function registerToken(
                        IVault vault,
                        bytes32 poolId,
                        IERC20 token,
                        address assetManager
                    ) internal {
                        IERC20[] memory tokens = new IERC20[](1);
                        tokens[0] = token;
                        address[] memory assetManagers = new address[](1);
                        assetManagers[0] = assetManager;
                        vault.registerTokens(poolId, tokens, assetManagers);
                    }
                    function deregisterToken(
                        IVault vault,
                        bytes32 poolId,
                        IERC20 token
                    ) internal {
                        IERC20[] memory tokens = new IERC20[](1);
                        tokens[0] = token;
                        vault.deregisterTokens(poolId, tokens);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/pool-utils/BasePoolUserData.sol";
                import "@balancer-labs/v2-interfaces/contracts/pool-utils/IRecoveryMode.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                import "./BasePoolAuthorization.sol";
                /**
                 * @notice Handle storage and state changes for pools that support "Recovery Mode".
                 *
                 * @dev This is intended to provide a safe way to exit any pool during some kind of emergency, to avoid locking funds
                 * in the event the pool enters a non-functional state (i.e., some code that normally runs during exits is causing
                 * them to revert).
                 *
                 * Recovery Mode is *not* the same as pausing the pool. The pause function is only available during a short window
                 * after factory deployment. Pausing can only be intentionally reversed during a buffer period, and the contract
                 * will permanently unpause itself thereafter. Paused pools are completely disabled, in a kind of suspended animation,
                 * until they are voluntarily or involuntarily unpaused.
                 *
                 * By contrast, a privileged account - typically a governance multisig - can place a pool in Recovery Mode at any
                 * time, and it is always reversible. The pool is *not* disabled while in this mode: though of course whatever
                 * condition prompted the transition to Recovery Mode has likely effectively disabled some functions. Rather,
                 * a special "clean" exit is enabled, which runs the absolute minimum code necessary to exit proportionally.
                 * In particular, stable pools do not attempt to compute the invariant (which is a complex, iterative calculation
                 * that can fail in extreme circumstances), and no protocol fees are collected.
                 *
                 * It is critical to ensure that turning on Recovery Mode would do no harm, if activated maliciously or in error.
                 */
                abstract contract RecoveryMode is IRecoveryMode, BasePoolAuthorization {
                    using FixedPoint for uint256;
                    using BasePoolUserData for bytes;
                    IVault private immutable _vault;
                    /**
                     * @dev Reverts if the contract is in Recovery Mode.
                     */
                    modifier whenNotInRecoveryMode() {
                        _ensureNotInRecoveryMode();
                        _;
                    }
                    constructor(IVault vault) {
                        _vault = vault;
                    }
                    /**
                     * @notice Enable recovery mode, which enables a special safe exit path for LPs.
                     * @dev Does not otherwise affect pool operations (beyond deferring payment of protocol fees), though some pools may
                     * perform certain operations in a "safer" manner that is less likely to fail, in an attempt to keep the pool
                     * running, even in a pathological state. Unlike the Pause operation, which is only available during a short window
                     * after factory deployment, Recovery Mode can always be enabled.
                     */
                    function enableRecoveryMode() external override authenticate {
                        // Unlike when recovery mode is disabled, derived contracts should *not* do anything when it is enabled.
                        // We do not want to make any calls that could fail and prevent the pool from entering recovery mode.
                        // Accordingly, this should have no effect, but for consistency with `disableRecoveryMode`, revert if
                        // recovery mode was already enabled.
                        _ensureNotInRecoveryMode();
                        _setRecoveryMode(true);
                        emit RecoveryModeStateChanged(true);
                    }
                    /**
                     * @notice Disable recovery mode, which disables the special safe exit path for LPs.
                     * @dev Protocol fees are not paid while in Recovery Mode, so it should only remain active for as long as strictly
                     * necessary.
                     */
                    function disableRecoveryMode() external override authenticate {
                        // Some derived contracts respond to disabling recovery mode with state changes (e.g., related to protocol fees,
                        // or otherwise ensuring that enabling and disabling recovery mode has no ill effects on LPs). When called
                        // outside of recovery mode, these state changes might lead to unexpected behavior.
                        _ensureInRecoveryMode();
                        _setRecoveryMode(false);
                        emit RecoveryModeStateChanged(false);
                    }
                    // Defer implementation for functions that require storage
                    /**
                     * @notice Override to check storage and return whether the pool is in Recovery Mode
                     */
                    function inRecoveryMode() public view virtual override returns (bool);
                    /**
                     * @dev Override to update storage and emit the event
                     *
                     * No complex code or external calls that could fail should be placed in the implementations,
                     * which could jeopardize the ability to enable and disable Recovery Mode.
                     */
                    function _setRecoveryMode(bool enabled) internal virtual;
                    /**
                     * @dev Reverts if the contract is not in Recovery Mode.
                     */
                    function _ensureInRecoveryMode() internal view {
                        _require(inRecoveryMode(), Errors.NOT_IN_RECOVERY_MODE);
                    }
                    /**
                     * @dev Reverts if the contract is in Recovery Mode.
                     */
                    function _ensureNotInRecoveryMode() internal view {
                        _require(!inRecoveryMode(), Errors.IN_RECOVERY_MODE);
                    }
                    /**
                     * @dev A minimal proportional exit, suitable as is for most pools: though not for pools with preminted BPT
                     * or other special considerations. Designed to be overridden if a pool needs to do extra processing,
                     * such as scaling a stored invariant, or caching the new total supply.
                     *
                     * No complex code or external calls should be made in derived contracts that override this!
                     */
                    function _doRecoveryModeExit(
                        uint256[] memory balances,
                        uint256 totalSupply,
                        bytes memory userData
                    ) internal virtual returns (uint256, uint256[] memory);
                    /**
                     * @dev Keep a reference to the Vault, for use in reentrancy protection function calls that require it.
                     */
                    function _getVault() internal view returns (IVault) {
                        return _vault;
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IAuthentication.sol";
                /**
                 * @dev Building block for performing access control on external functions.
                 *
                 * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
                 * to external functions to only make them callable by authorized accounts.
                 *
                 * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
                 */
                abstract contract Authentication is IAuthentication {
                    bytes32 private immutable _actionIdDisambiguator;
                    /**
                     * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
                     * multi contract systems.
                     *
                     * There are two main uses for it:
                     *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
                     *    unique. The contract's own address is a good option.
                     *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
                     *    shared by the entire family (and no other contract) should be used instead.
                     */
                    constructor(bytes32 actionIdDisambiguator) {
                        _actionIdDisambiguator = actionIdDisambiguator;
                    }
                    /**
                     * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
                     */
                    modifier authenticate() {
                        _authenticateCaller();
                        _;
                    }
                    /**
                     * @dev Reverts unless the caller is allowed to call the entry point function.
                     */
                    function _authenticateCaller() internal view {
                        bytes32 actionId = getActionId(msg.sig);
                        _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
                    }
                    function getActionId(bytes4 selector) public view override returns (bytes32) {
                        // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
                        // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
                        // multiple contracts.
                        return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
                    }
                    function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ISignaturesValidator.sol";
                import "../openzeppelin/EIP712.sol";
                /**
                 * @dev Utility for signing Solidity function calls.
                 */
                abstract contract EOASignaturesValidator is ISignaturesValidator, EIP712 {
                    // Replay attack prevention for each account.
                    mapping(address => uint256) internal _nextNonce;
                    function getDomainSeparator() public view override returns (bytes32) {
                        return _domainSeparatorV4();
                    }
                    function getNextNonce(address account) public view override returns (uint256) {
                        return _nextNonce[account];
                    }
                    function _ensureValidSignature(
                        address account,
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 errorCode
                    ) internal {
                        return _ensureValidSignature(account, structHash, signature, type(uint256).max, errorCode);
                    }
                    function _ensureValidSignature(
                        address account,
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 deadline,
                        uint256 errorCode
                    ) internal {
                        bytes32 digest = _hashTypedDataV4(structHash);
                        _require(_isValidSignature(account, digest, signature), errorCode);
                        // We could check for the deadline before validating the signature, but this leads to saner error processing (as
                        // we only care about expired deadlines if the signature is correct) and only affects the gas cost of the revert
                        // scenario, which will only occur infrequently, if ever.
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(deadline >= block.timestamp, Errors.EXPIRED_SIGNATURE);
                        // We only advance the nonce after validating the signature. This is irrelevant for this module, but it can be
                        // important in derived contracts that override _isValidSignature (e.g. SignaturesValidator), as we want for
                        // the observable state to still have the current nonce as the next valid one.
                        _nextNonce[account] += 1;
                    }
                    function _isValidSignature(
                        address account,
                        bytes32 digest,
                        bytes memory signature
                    ) internal view virtual returns (bool) {
                        _require(signature.length == 65, Errors.MALFORMED_SIGNATURE);
                        bytes32 r;
                        bytes32 s;
                        uint8 v;
                        // ecrecover takes the r, s and v signature parameters, and the only way to get them is to use assembly.
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            r := mload(add(signature, 0x20))
                            s := mload(add(signature, 0x40))
                            v := byte(0, mload(add(signature, 0x60)))
                        }
                        address recoveredAddress = ecrecover(digest, v, r, s);
                        // ecrecover returns the zero address on recover failure, so we need to handle that explicitly.
                        return (recoveredAddress != address(0) && recoveredAddress == account);
                    }
                    function _toArraySignature(
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) internal pure returns (bytes memory) {
                        bytes memory signature = new bytes(65);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            mstore(add(signature, 32), r)
                            mstore(add(signature, 64), s)
                            mstore8(add(signature, 96), v)
                        }
                        return signature;
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                library InputHelpers {
                    function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
                        _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
                    }
                    function ensureInputLengthMatch(
                        uint256 a,
                        uint256 b,
                        uint256 c
                    ) internal pure {
                        _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
                    }
                    function ensureArrayIsSorted(IERC20[] memory array) internal pure {
                        address[] memory addressArray;
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            addressArray := array
                        }
                        ensureArrayIsSorted(addressArray);
                    }
                    function ensureArrayIsSorted(address[] memory array) internal pure {
                        if (array.length < 2) {
                            return;
                        }
                        address previous = array[0];
                        for (uint256 i = 1; i < array.length; ++i) {
                            address current = array[i];
                            _require(previous < current, Errors.UNSORTED_ARRAY);
                            previous = current;
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "../math/FixedPoint.sol";
                import "../math/Math.sol";
                import "../openzeppelin/ERC20.sol";
                import "./InputHelpers.sol";
                // solhint-disable
                // To simplify Pool logic, all token balances and amounts are normalized to behave as if the token had 18 decimals.
                // e.g. When comparing DAI (18 decimals) and USDC (6 decimals), 1 USDC and 1 DAI would both be represented as 1e18,
                // whereas without scaling 1 USDC would be represented as 1e6.
                // This allows us to not consider differences in token decimals in the internal Pool maths, simplifying it greatly.
                // Single Value
                /**
                 * @dev Applies `scalingFactor` to `amount`, resulting in a larger or equal value depending on whether it needed
                 * scaling or not.
                 */
                function _upscale(uint256 amount, uint256 scalingFactor) pure returns (uint256) {
                    // Upscale rounding wouldn't necessarily always go in the same direction: in a swap for example the balance of
                    // token in should be rounded up, and that of token out rounded down. This is the only place where we round in
                    // the same direction for all amounts, as the impact of this rounding is expected to be minimal.
                    return FixedPoint.mulDown(amount, scalingFactor);
                }
                /**
                 * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
                 * whether it needed scaling or not. The result is rounded down.
                 */
                function _downscaleDown(uint256 amount, uint256 scalingFactor) pure returns (uint256) {
                    return FixedPoint.divDown(amount, scalingFactor);
                }
                /**
                 * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
                 * whether it needed scaling or not. The result is rounded up.
                 */
                function _downscaleUp(uint256 amount, uint256 scalingFactor) pure returns (uint256) {
                    return FixedPoint.divUp(amount, scalingFactor);
                }
                // Array
                /**
                 * @dev Same as `_upscale`, but for an entire array. This function does not return anything, but instead *mutates*
                 * the `amounts` array.
                 */
                function _upscaleArray(uint256[] memory amounts, uint256[] memory scalingFactors) pure {
                    uint256 length = amounts.length;
                    InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
                    for (uint256 i = 0; i < length; ++i) {
                        amounts[i] = FixedPoint.mulDown(amounts[i], scalingFactors[i]);
                    }
                }
                /**
                 * @dev Same as `_downscaleDown`, but for an entire array. This function does not return anything, but instead
                 * *mutates* the `amounts` array.
                 */
                function _downscaleDownArray(uint256[] memory amounts, uint256[] memory scalingFactors) pure {
                    uint256 length = amounts.length;
                    InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
                    for (uint256 i = 0; i < length; ++i) {
                        amounts[i] = FixedPoint.divDown(amounts[i], scalingFactors[i]);
                    }
                }
                /**
                 * @dev Same as `_downscaleUp`, but for an entire array. This function does not return anything, but instead
                 * *mutates* the `amounts` array.
                 */
                function _downscaleUpArray(uint256[] memory amounts, uint256[] memory scalingFactors) pure {
                    uint256 length = amounts.length;
                    InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
                    for (uint256 i = 0; i < length; ++i) {
                        amounts[i] = FixedPoint.divUp(amounts[i], scalingFactors[i]);
                    }
                }
                function _computeScalingFactor(IERC20 token) view returns (uint256) {
                    // Tokens that don't implement the `decimals` method are not supported.
                    uint256 tokenDecimals = ERC20(address(token)).decimals();
                    // Tokens with more than 18 decimals are not supported.
                    uint256 decimalsDifference = Math.sub(18, tokenDecimals);
                    return FixedPoint.ONE * 10**decimalsDifference;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ITemporarilyPausable.sol";
                /**
                 * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
                 * used as an emergency switch in case a security vulnerability or threat is identified.
                 *
                 * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
                 * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
                 * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
                 * analysis later determines there was a false alarm.
                 *
                 * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
                 * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
                 * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
                 *
                 * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
                 * irreversible.
                 */
                abstract contract TemporarilyPausable is ITemporarilyPausable {
                    // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
                    // solhint-disable not-rely-on-time
                    uint256 private immutable _pauseWindowEndTime;
                    uint256 private immutable _bufferPeriodEndTime;
                    bool private _paused;
                    constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
                        _require(pauseWindowDuration <= PausableConstants.MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
                        _require(
                            bufferPeriodDuration <= PausableConstants.MAX_BUFFER_PERIOD_DURATION,
                            Errors.MAX_BUFFER_PERIOD_DURATION
                        );
                        uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
                        _pauseWindowEndTime = pauseWindowEndTime;
                        _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
                    }
                    /**
                     * @dev Reverts if the contract is paused.
                     */
                    modifier whenNotPaused() {
                        _ensureNotPaused();
                        _;
                    }
                    /**
                     * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
                     * Period.
                     */
                    function getPausedState()
                        external
                        view
                        override
                        returns (
                            bool paused,
                            uint256 pauseWindowEndTime,
                            uint256 bufferPeriodEndTime
                        )
                    {
                        paused = !_isNotPaused();
                        pauseWindowEndTime = _getPauseWindowEndTime();
                        bufferPeriodEndTime = _getBufferPeriodEndTime();
                    }
                    /**
                     * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
                     * unpaused until the end of the Buffer Period.
                     *
                     * Once the Buffer Period expires, this function reverts unconditionally.
                     */
                    function _setPaused(bool paused) internal {
                        if (paused) {
                            _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
                        } else {
                            _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
                        }
                        _paused = paused;
                        emit PausedStateChanged(paused);
                    }
                    /**
                     * @dev Reverts if the contract is paused.
                     */
                    function _ensureNotPaused() internal view {
                        _require(_isNotPaused(), Errors.PAUSED);
                    }
                    /**
                     * @dev Reverts if the contract is not paused.
                     */
                    function _ensurePaused() internal view {
                        _require(!_isNotPaused(), Errors.NOT_PAUSED);
                    }
                    /**
                     * @dev Returns true if the contract is unpaused.
                     *
                     * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
                     * longer accessed.
                     */
                    function _isNotPaused() internal view returns (bool) {
                        // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
                        return block.timestamp > _getBufferPeriodEndTime() || !_paused;
                    }
                    // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
                    function _getPauseWindowEndTime() private view returns (uint256) {
                        return _pauseWindowEndTime;
                    }
                    function _getBufferPeriodEndTime() private view returns (uint256) {
                        return _bufferPeriodEndTime;
                    }
                }
                /**
                 * @dev Keep the maximum durations in a single place.
                 */
                library PausableConstants {
                    uint256 public constant MAX_PAUSE_WINDOW_DURATION = 270 days;
                    uint256 public constant MAX_BUFFER_PERIOD_DURATION = 90 days;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "../math/Math.sol";
                /**
                 * @dev Library for encoding and decoding values stored inside a 256 bit word. Typically used to pack multiple values in
                 * a single storage slot, saving gas by performing less storage accesses.
                 *
                 * Each value is defined by its size and the least significant bit in the word, also known as offset. For example, two
                 * 128 bit values may be encoded in a word by assigning one an offset of 0, and the other an offset of 128.
                 *
                 * We could use Solidity structs to pack values together in a single storage slot instead of relying on a custom and
                 * error-prone library, but unfortunately Solidity only allows for structs to live in either storage, calldata or
                 * memory. Because a memory struct uses not just memory but also a slot in the stack (to store its memory location),
                 * using memory for word-sized values (i.e. of 256 bits or less) is strictly less gas performant, and doesn't even
                 * prevent stack-too-deep issues. This is compounded by the fact that Balancer contracts typically are memory-intensive,
                 * and the cost of accesing memory increases quadratically with the number of allocated words. Manual packing and
                 * unpacking is therefore the preferred approach.
                 */
                library WordCodec {
                    // solhint-disable no-inline-assembly
                    // Masks are values with the least significant N bits set. They can be used to extract an encoded value from a word,
                    // or to insert a new one replacing the old.
                    uint256 private constant _MASK_1 = 2**(1) - 1;
                    uint256 private constant _MASK_192 = 2**(192) - 1;
                    // In-place insertion
                    /**
                     * @dev Inserts an unsigned integer of bitLength, shifted by an offset, into a 256 bit word,
                     * replacing the old value. Returns the new word.
                     */
                    function insertUint(
                        bytes32 word,
                        uint256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (bytes32 result) {
                        _validateEncodingParams(value, offset, bitLength);
                        // Equivalent to:
                        // uint256 mask = (1 << bitLength) - 1;
                        // bytes32 clearedWord = bytes32(uint256(word) & ~(mask << offset));
                        // result = clearedWord | bytes32(value << offset);
                        assembly {
                            let mask := sub(shl(bitLength, 1), 1)
                            let clearedWord := and(word, not(shl(offset, mask)))
                            result := or(clearedWord, shl(offset, value))
                        }
                    }
                    /**
                     * @dev Inserts a signed integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                     * the new word.
                     *
                     * Assumes `value` can be represented using `bitLength` bits.
                     */
                    function insertInt(
                        bytes32 word,
                        int256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (bytes32) {
                        _validateEncodingParams(value, offset, bitLength);
                        uint256 mask = (1 << bitLength) - 1;
                        bytes32 clearedWord = bytes32(uint256(word) & ~(mask << offset));
                        // Integer values need masking to remove the upper bits of negative values.
                        return clearedWord | bytes32((uint256(value) & mask) << offset);
                    }
                    // Encoding
                    /**
                     * @dev Encodes an unsigned integer shifted by an offset. Ensures value fits within
                     * `bitLength` bits.
                     *
                     * The return value can be ORed bitwise with other encoded values to form a 256 bit word.
                     */
                    function encodeUint(
                        uint256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (bytes32) {
                        _validateEncodingParams(value, offset, bitLength);
                        return bytes32(value << offset);
                    }
                    /**
                     * @dev Encodes a signed integer shifted by an offset.
                     *
                     * The return value can be ORed bitwise with other encoded values to form a 256 bit word.
                     */
                    function encodeInt(
                        int256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (bytes32) {
                        _validateEncodingParams(value, offset, bitLength);
                        uint256 mask = (1 << bitLength) - 1;
                        // Integer values need masking to remove the upper bits of negative values.
                        return bytes32((uint256(value) & mask) << offset);
                    }
                    // Decoding
                    /**
                     * @dev Decodes and returns an unsigned integer with `bitLength` bits, shifted by an offset, from a 256 bit word.
                     */
                    function decodeUint(
                        bytes32 word,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = uint256(word >> offset) & ((1 << bitLength) - 1);
                        assembly {
                            result := and(shr(offset, word), sub(shl(bitLength, 1), 1))
                        }
                    }
                    /**
                     * @dev Decodes and returns a signed integer with `bitLength` bits, shifted by an offset, from a 256 bit word.
                     */
                    function decodeInt(
                        bytes32 word,
                        uint256 offset,
                        uint256 bitLength
                    ) internal pure returns (int256 result) {
                        int256 maxInt = int256((1 << (bitLength - 1)) - 1);
                        uint256 mask = (1 << bitLength) - 1;
                        int256 value = int256(uint256(word >> offset) & mask);
                        // In case the decoded value is greater than the max positive integer that can be represented with bitLength
                        // bits, we know it was originally a negative integer. Therefore, we mask it to restore the sign in the 256 bit
                        // representation.
                        //
                        // Equivalent to:
                        // result = value > maxInt ? (value | int256(~mask)) : value;
                        assembly {
                            result := or(mul(gt(value, maxInt), not(mask)), value)
                        }
                    }
                    // Special cases
                    /**
                     * @dev Decodes and returns a boolean shifted by an offset from a 256 bit word.
                     */
                    function decodeBool(bytes32 word, uint256 offset) internal pure returns (bool result) {
                        // Equivalent to:
                        // result = (uint256(word >> offset) & 1) == 1;
                        assembly {
                            result := and(shr(offset, word), 1)
                        }
                    }
                    /**
                     * @dev Inserts a 192 bit value shifted by an offset into a 256 bit word, replacing the old value.
                     * Returns the new word.
                     *
                     * Assumes `value` can be represented using 192 bits.
                     */
                    function insertBits192(
                        bytes32 word,
                        bytes32 value,
                        uint256 offset
                    ) internal pure returns (bytes32) {
                        bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_192 << offset));
                        return clearedWord | bytes32((uint256(value) & _MASK_192) << offset);
                    }
                    /**
                     * @dev Inserts a boolean value shifted by an offset into a 256 bit word, replacing the old value. Returns the new
                     * word.
                     */
                    function insertBool(
                        bytes32 word,
                        bool value,
                        uint256 offset
                    ) internal pure returns (bytes32 result) {
                        // Equivalent to:
                        // bytes32 clearedWord = bytes32(uint256(word) & ~(1 << offset));
                        // bytes32 referenceInsertBool = clearedWord | bytes32(uint256(value ? 1 : 0) << offset);
                        assembly {
                            let clearedWord := and(word, not(shl(offset, 1)))
                            result := or(clearedWord, shl(offset, value))
                        }
                    }
                    // Helpers
                    function _validateEncodingParams(
                        uint256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) private pure {
                        _require(offset < 256, Errors.OUT_OF_BOUNDS);
                        // We never accept 256 bit values (which would make the codec pointless), and the larger the offset the smaller
                        // the maximum bit length.
                        _require(bitLength >= 1 && bitLength <= Math.min(255, 256 - offset), Errors.OUT_OF_BOUNDS);
                        // Testing unsigned values for size is straightforward: their upper bits must be cleared.
                        _require(value >> bitLength == 0, Errors.CODEC_OVERFLOW);
                    }
                    function _validateEncodingParams(
                        int256 value,
                        uint256 offset,
                        uint256 bitLength
                    ) private pure {
                        _require(offset < 256, Errors.OUT_OF_BOUNDS);
                        // We never accept 256 bit values (which would make the codec pointless), and the larger the offset the smaller
                        // the maximum bit length.
                        _require(bitLength >= 1 && bitLength <= Math.min(255, 256 - offset), Errors.OUT_OF_BOUNDS);
                        // Testing signed values for size is a bit more involved.
                        if (value >= 0) {
                            // For positive values, we can simply check that the upper bits are clear. Notice we remove one bit from the
                            // length for the sign bit.
                            _require(value >> (bitLength - 1) == 0, Errors.CODEC_OVERFLOW);
                        } else {
                            // Negative values can receive the same treatment by making them positive, with the caveat that the range
                            // for negative values in two's complement supports one more value than for the positive case.
                            _require(Math.abs(value + 1) >> (bitLength - 1) == 0, Errors.CODEC_OVERFLOW);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "./LogExpMath.sol";
                /* solhint-disable private-vars-leading-underscore */
                library FixedPoint {
                    // solhint-disable no-inline-assembly
                    uint256 internal constant ONE = 1e18; // 18 decimal places
                    uint256 internal constant TWO = 2 * ONE;
                    uint256 internal constant FOUR = 4 * ONE;
                    uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
                    // Minimum base for the power function when the exponent is 'free' (larger than ONE).
                    uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        // Fixed Point addition is the same as regular checked addition
                        uint256 c = a + b;
                        _require(c >= a, Errors.ADD_OVERFLOW);
                        return c;
                    }
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        // Fixed Point addition is the same as regular checked addition
                        _require(b <= a, Errors.SUB_OVERFLOW);
                        uint256 c = a - b;
                        return c;
                    }
                    function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 product = a * b;
                        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                        return product / ONE;
                    }
                    function mulUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        uint256 product = a * b;
                        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, if x == 0 then the result is zero
                        //
                        // Equivalent to:
                        // result = product == 0 ? 0 : ((product - 1) / FixedPoint.ONE) + 1;
                        assembly {
                            result := mul(iszero(iszero(product)), add(div(sub(product, 1), ONE), 1))
                        }
                    }
                    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        uint256 aInflated = a * ONE;
                        _require(a == 0 || aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        return aInflated / b;
                    }
                    function divUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        uint256 aInflated = a * ONE;
                        _require(a == 0 || aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, if x == 0 then the result is zero
                        //
                        // Equivalent to:
                        // result = a == 0 ? 0 : (a * FixedPoint.ONE - 1) / b + 1;
                        assembly {
                            result := mul(iszero(iszero(aInflated)), add(div(sub(aInflated, 1), b), 1))
                        }
                    }
                    /**
                     * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
                     * the true value (that is, the error function expected - actual is always positive).
                     */
                    function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
                        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
                        // and 80/20 Weighted Pools
                        if (y == ONE) {
                            return x;
                        } else if (y == TWO) {
                            return mulDown(x, x);
                        } else if (y == FOUR) {
                            uint256 square = mulDown(x, x);
                            return mulDown(square, square);
                        } else {
                            uint256 raw = LogExpMath.pow(x, y);
                            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                            if (raw < maxError) {
                                return 0;
                            } else {
                                return sub(raw, maxError);
                            }
                        }
                    }
                    /**
                     * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
                     * the true value (that is, the error function expected - actual is always negative).
                     */
                    function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
                        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
                        // and 80/20 Weighted Pools
                        if (y == ONE) {
                            return x;
                        } else if (y == TWO) {
                            return mulUp(x, x);
                        } else if (y == FOUR) {
                            uint256 square = mulUp(x, x);
                            return mulUp(square, square);
                        } else {
                            uint256 raw = LogExpMath.pow(x, y);
                            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                            return add(raw, maxError);
                        }
                    }
                    /**
                     * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
                     *
                     * Useful when computing the complement for values with some level of relative error, as it strips this error and
                     * prevents intermediate negative values.
                     */
                    function complement(uint256 x) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = (x < ONE) ? (ONE - x) : 0;
                        assembly {
                            result := mul(lt(x, ONE), sub(ONE, x))
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                // Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
                // documentation files (the “Software”), to deal in the Software without restriction, including without limitation the
                // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
                // permit persons to whom the Software is furnished to do so, subject to the following conditions:
                // The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
                // Software.
                // THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
                // WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
                // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
                // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /* solhint-disable */
                /**
                 * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
                 *
                 * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
                 * exponentiation and logarithm (where the base is Euler's number).
                 *
                 * @author Fernando Martinelli - @fernandomartinelli
                 * @author Sergio Yuhjtman - @sergioyuhjtman
                 * @author Daniel Fernandez - @dmf7z
                 */
                library LogExpMath {
                    // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
                    // two numbers, and multiply by ONE when dividing them.
                    // All arguments and return values are 18 decimal fixed point numbers.
                    int256 constant ONE_18 = 1e18;
                    // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
                    // case of ln36, 36 decimals.
                    int256 constant ONE_20 = 1e20;
                    int256 constant ONE_36 = 1e36;
                    // The domain of natural exponentiation is bound by the word size and number of decimals used.
                    //
                    // Because internally the result will be stored using 20 decimals, the largest possible result is
                    // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
                    // The smallest possible result is 10^(-18), which makes largest negative argument
                    // ln(10^(-18)) = -41.446531673892822312.
                    // We use 130.0 and -41.0 to have some safety margin.
                    int256 constant MAX_NATURAL_EXPONENT = 130e18;
                    int256 constant MIN_NATURAL_EXPONENT = -41e18;
                    // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
                    // 256 bit integer.
                    int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
                    int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
                    uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
                    // 18 decimal constants
                    int256 constant x0 = 128000000000000000000; // 2ˆ7
                    int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
                    int256 constant x1 = 64000000000000000000; // 2ˆ6
                    int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
                    // 20 decimal constants
                    int256 constant x2 = 3200000000000000000000; // 2ˆ5
                    int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
                    int256 constant x3 = 1600000000000000000000; // 2ˆ4
                    int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
                    int256 constant x4 = 800000000000000000000; // 2ˆ3
                    int256 constant a4 = 298095798704172827474000; // eˆ(x4)
                    int256 constant x5 = 400000000000000000000; // 2ˆ2
                    int256 constant a5 = 5459815003314423907810; // eˆ(x5)
                    int256 constant x6 = 200000000000000000000; // 2ˆ1
                    int256 constant a6 = 738905609893065022723; // eˆ(x6)
                    int256 constant x7 = 100000000000000000000; // 2ˆ0
                    int256 constant a7 = 271828182845904523536; // eˆ(x7)
                    int256 constant x8 = 50000000000000000000; // 2ˆ-1
                    int256 constant a8 = 164872127070012814685; // eˆ(x8)
                    int256 constant x9 = 25000000000000000000; // 2ˆ-2
                    int256 constant a9 = 128402541668774148407; // eˆ(x9)
                    int256 constant x10 = 12500000000000000000; // 2ˆ-3
                    int256 constant a10 = 113314845306682631683; // eˆ(x10)
                    int256 constant x11 = 6250000000000000000; // 2ˆ-4
                    int256 constant a11 = 106449445891785942956; // eˆ(x11)
                    /**
                     * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
                     *
                     * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
                     */
                    function pow(uint256 x, uint256 y) internal pure returns (uint256) {
                        if (y == 0) {
                            // We solve the 0^0 indetermination by making it equal one.
                            return uint256(ONE_18);
                        }
                        if (x == 0) {
                            return 0;
                        }
                        // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
                        // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
                        // x^y = exp(y * ln(x)).
                        // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
                        _require(x >> 255 == 0, Errors.X_OUT_OF_BOUNDS);
                        int256 x_int256 = int256(x);
                        // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
                        // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
                        // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
                        _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
                        int256 y_int256 = int256(y);
                        int256 logx_times_y;
                        if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
                            int256 ln_36_x = _ln_36(x_int256);
                            // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
                            // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
                            // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
                            // (downscaled) last 18 decimals.
                            logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
                        } else {
                            logx_times_y = _ln(x_int256) * y_int256;
                        }
                        logx_times_y /= ONE_18;
                        // Finally, we compute exp(y * ln(x)) to arrive at x^y
                        _require(
                            MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
                            Errors.PRODUCT_OUT_OF_BOUNDS
                        );
                        return uint256(exp(logx_times_y));
                    }
                    /**
                     * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
                     *
                     * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
                     */
                    function exp(int256 x) internal pure returns (int256) {
                        _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
                        if (x < 0) {
                            // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
                            // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
                            // Fixed point division requires multiplying by ONE_18.
                            return ((ONE_18 * ONE_18) / exp(-x));
                        }
                        // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
                        // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
                        // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
                        // decomposition.
                        // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
                        // decomposition, which will be lower than the smallest x_n.
                        // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
                        // We mutate x by subtracting x_n, making it the remainder of the decomposition.
                        // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
                        // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
                        // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
                        // decomposition.
                        // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
                        // it and compute the accumulated product.
                        int256 firstAN;
                        if (x >= x0) {
                            x -= x0;
                            firstAN = a0;
                        } else if (x >= x1) {
                            x -= x1;
                            firstAN = a1;
                        } else {
                            firstAN = 1; // One with no decimal places
                        }
                        // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
                        // smaller terms.
                        x *= 100;
                        // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
                        // one. Recall that fixed point multiplication requires dividing by ONE_20.
                        int256 product = ONE_20;
                        if (x >= x2) {
                            x -= x2;
                            product = (product * a2) / ONE_20;
                        }
                        if (x >= x3) {
                            x -= x3;
                            product = (product * a3) / ONE_20;
                        }
                        if (x >= x4) {
                            x -= x4;
                            product = (product * a4) / ONE_20;
                        }
                        if (x >= x5) {
                            x -= x5;
                            product = (product * a5) / ONE_20;
                        }
                        if (x >= x6) {
                            x -= x6;
                            product = (product * a6) / ONE_20;
                        }
                        if (x >= x7) {
                            x -= x7;
                            product = (product * a7) / ONE_20;
                        }
                        if (x >= x8) {
                            x -= x8;
                            product = (product * a8) / ONE_20;
                        }
                        if (x >= x9) {
                            x -= x9;
                            product = (product * a9) / ONE_20;
                        }
                        // x10 and x11 are unnecessary here since we have high enough precision already.
                        // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
                        // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
                        int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
                        int256 term; // Each term in the sum, where the nth term is (x^n / n!).
                        // The first term is simply x.
                        term = x;
                        seriesSum += term;
                        // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
                        // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
                        term = ((term * x) / ONE_20) / 2;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 3;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 4;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 5;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 6;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 7;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 8;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 9;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 10;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 11;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 12;
                        seriesSum += term;
                        // 12 Taylor terms are sufficient for 18 decimal precision.
                        // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
                        // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
                        // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
                        // and then drop two digits to return an 18 decimal value.
                        return (((product * seriesSum) / ONE_20) * firstAN) / 100;
                    }
                    /**
                     * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument.
                     */
                    function log(int256 arg, int256 base) internal pure returns (int256) {
                        // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
                        // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
                        // upscaling.
                        int256 logBase;
                        if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
                            logBase = _ln_36(base);
                        } else {
                            logBase = _ln(base) * ONE_18;
                        }
                        int256 logArg;
                        if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
                            logArg = _ln_36(arg);
                        } else {
                            logArg = _ln(arg) * ONE_18;
                        }
                        // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
                        return (logArg * ONE_18) / logBase;
                    }
                    /**
                     * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                     */
                    function ln(int256 a) internal pure returns (int256) {
                        // The real natural logarithm is not defined for negative numbers or zero.
                        _require(a > 0, Errors.OUT_OF_BOUNDS);
                        if (LN_36_LOWER_BOUND < a && a < LN_36_UPPER_BOUND) {
                            return _ln_36(a) / ONE_18;
                        } else {
                            return _ln(a);
                        }
                    }
                    /**
                     * @dev Internal natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                     */
                    function _ln(int256 a) private pure returns (int256) {
                        if (a < ONE_18) {
                            // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
                            // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
                            // Fixed point division requires multiplying by ONE_18.
                            return (-_ln((ONE_18 * ONE_18) / a));
                        }
                        // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
                        // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
                        // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
                        // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
                        // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
                        // decomposition, which will be lower than the smallest a_n.
                        // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
                        // We mutate a by subtracting a_n, making it the remainder of the decomposition.
                        // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
                        // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
                        // ONE_18 to convert them to fixed point.
                        // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
                        // by it and compute the accumulated sum.
                        int256 sum = 0;
                        if (a >= a0 * ONE_18) {
                            a /= a0; // Integer, not fixed point division
                            sum += x0;
                        }
                        if (a >= a1 * ONE_18) {
                            a /= a1; // Integer, not fixed point division
                            sum += x1;
                        }
                        // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
                        sum *= 100;
                        a *= 100;
                        // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
                        if (a >= a2) {
                            a = (a * ONE_20) / a2;
                            sum += x2;
                        }
                        if (a >= a3) {
                            a = (a * ONE_20) / a3;
                            sum += x3;
                        }
                        if (a >= a4) {
                            a = (a * ONE_20) / a4;
                            sum += x4;
                        }
                        if (a >= a5) {
                            a = (a * ONE_20) / a5;
                            sum += x5;
                        }
                        if (a >= a6) {
                            a = (a * ONE_20) / a6;
                            sum += x6;
                        }
                        if (a >= a7) {
                            a = (a * ONE_20) / a7;
                            sum += x7;
                        }
                        if (a >= a8) {
                            a = (a * ONE_20) / a8;
                            sum += x8;
                        }
                        if (a >= a9) {
                            a = (a * ONE_20) / a9;
                            sum += x9;
                        }
                        if (a >= a10) {
                            a = (a * ONE_20) / a10;
                            sum += x10;
                        }
                        if (a >= a11) {
                            a = (a * ONE_20) / a11;
                            sum += x11;
                        }
                        // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
                        // that converges rapidly for values of `a` close to one - the same one used in ln_36.
                        // Let z = (a - 1) / (a + 1).
                        // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                        // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
                        // division by ONE_20.
                        int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
                        int256 z_squared = (z * z) / ONE_20;
                        // num is the numerator of the series: the z^(2 * n + 1) term
                        int256 num = z;
                        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                        int256 seriesSum = num;
                        // In each step, the numerator is multiplied by z^2
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 3;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 5;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 7;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 9;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 11;
                        // 6 Taylor terms are sufficient for 36 decimal precision.
                        // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
                        seriesSum *= 2;
                        // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
                        // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
                        // value.
                        return (sum + seriesSum) / 100;
                    }
                    /**
                     * @dev Intrnal high precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
                     * for x close to one.
                     *
                     * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
                     */
                    function _ln_36(int256 x) private pure returns (int256) {
                        // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
                        // worthwhile.
                        // First, we transform x to a 36 digit fixed point value.
                        x *= ONE_18;
                        // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
                        // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                        // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
                        // division by ONE_36.
                        int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
                        int256 z_squared = (z * z) / ONE_36;
                        // num is the numerator of the series: the z^(2 * n + 1) term
                        int256 num = z;
                        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                        int256 seriesSum = num;
                        // In each step, the numerator is multiplied by z^2
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 3;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 5;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 7;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 9;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 11;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 13;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 15;
                        // 8 Taylor terms are sufficient for 36 decimal precision.
                        // All that remains is multiplying by 2 (non fixed point).
                        return seriesSum * 2;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
                 * Adapted from OpenZeppelin's SafeMath library.
                 */
                library Math {
                    // solhint-disable no-inline-assembly
                    /**
                     * @dev Returns the absolute value of a signed integer.
                     */
                    function abs(int256 a) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = a > 0 ? uint256(a) : uint256(-a)
                        assembly {
                            let s := sar(255, a)
                            result := sub(xor(a, s), s)
                        }
                    }
                    /**
                     * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
                     */
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a + b;
                        _require(c >= a, Errors.ADD_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the addition of two signed integers, reverting on overflow.
                     */
                    function add(int256 a, int256 b) internal pure returns (int256) {
                        int256 c = a + b;
                        _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
                     */
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b <= a, Errors.SUB_OVERFLOW);
                        uint256 c = a - b;
                        return c;
                    }
                    /**
                     * @dev Returns the subtraction of two signed integers, reverting on overflow.
                     */
                    function sub(int256 a, int256 b) internal pure returns (int256) {
                        int256 c = a - b;
                        _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the largest of two numbers of 256 bits.
                     */
                    function max(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = (a < b) ? b : a;
                        assembly {
                            result := sub(a, mul(sub(a, b), lt(a, b)))
                        }
                    }
                    /**
                     * @dev Returns the smallest of two numbers of 256 bits.
                     */
                    function min(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        // Equivalent to `result = (a < b) ? a : b`
                        assembly {
                            result := sub(a, mul(sub(a, b), gt(a, b)))
                        }
                    }
                    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a * b;
                        _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
                        return c;
                    }
                    function div(
                        uint256 a,
                        uint256 b,
                        bool roundUp
                    ) internal pure returns (uint256) {
                        return roundUp ? divUp(a, b) : divDown(a, b);
                    }
                    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        return a / b;
                    }
                    function divUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        // Equivalent to:
                        // result = a == 0 ? 0 : 1 + (a - 1) / b;
                        assembly {
                            result := mul(iszero(iszero(a)), add(1, div(sub(a, 1), b)))
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                /**
                 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
                 *
                 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
                 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
                 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
                 *
                 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
                 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
                 * ({_hashTypedDataV4}).
                 *
                 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
                 * the chain id to protect against replay attacks on an eventual fork of the chain.
                 *
                 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
                 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
                 *
                 * _Available since v3.4._
                 */
                abstract contract EIP712 {
                    /* solhint-disable var-name-mixedcase */
                    bytes32 private immutable _HASHED_NAME;
                    bytes32 private immutable _HASHED_VERSION;
                    bytes32 private immutable _TYPE_HASH;
                    /* solhint-enable var-name-mixedcase */
                    /**
                     * @dev Initializes the domain separator and parameter caches.
                     *
                     * The meaning of `name` and `version` is specified in
                     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
                     *
                     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
                     * - `version`: the current major version of the signing domain.
                     *
                     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
                     * contract upgrade].
                     */
                    constructor(string memory name, string memory version) {
                        _HASHED_NAME = keccak256(bytes(name));
                        _HASHED_VERSION = keccak256(bytes(version));
                        _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
                    }
                    /**
                     * @dev Returns the domain separator for the current chain.
                     */
                    function _domainSeparatorV4() internal view virtual returns (bytes32) {
                        return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
                    }
                    /**
                     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
                     * function returns the hash of the fully encoded EIP712 message for this domain.
                     *
                     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
                     *
                     * ```solidity
                     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
                     *     keccak256("Mail(address to,string contents)"),
                     *     mailTo,
                     *     keccak256(bytes(mailContents))
                     * )));
                     * address signer = ECDSA.recover(digest, signature);
                     * ```
                     */
                    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                        return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
                    }
                    // solc-ignore-next-line func-mutability
                    function _getChainId() private view returns (uint256 chainId) {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            chainId := chainid()
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "./SafeMath.sol";
                /**
                 * @dev Implementation of the {IERC20} interface.
                 *
                 * This implementation is agnostic to the way tokens are created. This means
                 * that a supply mechanism has to be added in a derived contract using {_mint}.
                 * For a generic mechanism see {ERC20PresetMinterPauser}.
                 *
                 * TIP: For a detailed writeup see our guide
                 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
                 * to implement supply mechanisms].
                 *
                 * We have followed general OpenZeppelin guidelines: functions revert instead
                 * of returning `false` on failure. This behavior is nonetheless conventional
                 * and does not conflict with the expectations of ERC20 applications.
                 *
                 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
                 * This allows applications to reconstruct the allowance for all accounts just
                 * by listening to said events. Other implementations of the EIP may not emit
                 * these events, as it isn't required by the specification.
                 *
                 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
                 * functions have been added to mitigate the well-known issues around setting
                 * allowances. See {IERC20-approve}.
                 */
                contract ERC20 is IERC20 {
                    using SafeMath for uint256;
                    mapping(address => uint256) private _balances;
                    mapping(address => mapping(address => uint256)) private _allowances;
                    uint256 private _totalSupply;
                    string private _name;
                    string private _symbol;
                    uint8 private _decimals;
                    /**
                     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
                     * a default value of 18.
                     *
                     * To select a different value for {decimals}, use {_setupDecimals}.
                     *
                     * All three of these values are immutable: they can only be set once during
                     * construction.
                     */
                    constructor(string memory name_, string memory symbol_) {
                        _name = name_;
                        _symbol = symbol_;
                        _decimals = 18;
                    }
                    /**
                     * @dev Returns the name of the token.
                     */
                    function name() public view returns (string memory) {
                        return _name;
                    }
                    /**
                     * @dev Returns the symbol of the token, usually a shorter version of the
                     * name.
                     */
                    function symbol() public view returns (string memory) {
                        return _symbol;
                    }
                    /**
                     * @dev Returns the number of decimals used to get its user representation.
                     * For example, if `decimals` equals `2`, a balance of `505` tokens should
                     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
                     *
                     * Tokens usually opt for a value of 18, imitating the relationship between
                     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
                     * called.
                     *
                     * NOTE: This information is only used for _display_ purposes: it in
                     * no way affects any of the arithmetic of the contract, including
                     * {IERC20-balanceOf} and {IERC20-transfer}.
                     */
                    function decimals() public view returns (uint8) {
                        return _decimals;
                    }
                    /**
                     * @dev See {IERC20-totalSupply}. The total supply should only be read using this function
                     *
                     * Can be overridden by derived contracts to store the total supply in a different way (e.g. packed with other
                     * storage values).
                     */
                    function totalSupply() public view virtual override returns (uint256) {
                        return _totalSupply;
                    }
                    /**
                     * @dev Sets a new value for the total supply. It should only be set using this function.
                     *
                     * * Can be overridden by derived contracts to store the total supply in a different way (e.g. packed with other
                     * storage values).
                     */
                    function _setTotalSupply(uint256 value) internal virtual {
                        _totalSupply = value;
                    }
                    /**
                     * @dev See {IERC20-balanceOf}.
                     */
                    function balanceOf(address account) public view override returns (uint256) {
                        return _balances[account];
                    }
                    /**
                     * @dev See {IERC20-transfer}.
                     *
                     * Requirements:
                     *
                     * - `recipient` cannot be the zero address.
                     * - the caller must have a balance of at least `amount`.
                     */
                    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
                        _transfer(msg.sender, recipient, amount);
                        return true;
                    }
                    /**
                     * @dev See {IERC20-allowance}.
                     */
                    function allowance(address owner, address spender) public view virtual override returns (uint256) {
                        return _allowances[owner][spender];
                    }
                    /**
                     * @dev See {IERC20-approve}.
                     *
                     * Requirements:
                     *
                     * - `spender` cannot be the zero address.
                     */
                    function approve(address spender, uint256 amount) public virtual override returns (bool) {
                        _approve(msg.sender, spender, amount);
                        return true;
                    }
                    /**
                     * @dev See {IERC20-transferFrom}.
                     *
                     * Emits an {Approval} event indicating the updated allowance. This is not
                     * required by the EIP. See the note at the beginning of {ERC20}.
                     *
                     * Requirements:
                     *
                     * - `sender` and `recipient` cannot be the zero address.
                     * - `sender` must have a balance of at least `amount`.
                     * - the caller must have allowance for ``sender``'s tokens of at least
                     * `amount`.
                     */
                    function transferFrom(
                        address sender,
                        address recipient,
                        uint256 amount
                    ) public virtual override returns (bool) {
                        _transfer(sender, recipient, amount);
                        _approve(
                            sender,
                            msg.sender,
                            _allowances[sender][msg.sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE)
                        );
                        return true;
                    }
                    /**
                     * @dev Atomically increases the allowance granted to `spender` by the caller.
                     *
                     * This is an alternative to {approve} that can be used as a mitigation for
                     * problems described in {IERC20-approve}.
                     *
                     * Emits an {Approval} event indicating the updated allowance.
                     *
                     * Requirements:
                     *
                     * - `spender` cannot be the zero address.
                     */
                    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                        _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
                        return true;
                    }
                    /**
                     * @dev Atomically decreases the allowance granted to `spender` by the caller.
                     *
                     * This is an alternative to {approve} that can be used as a mitigation for
                     * problems described in {IERC20-approve}.
                     *
                     * Emits an {Approval} event indicating the updated allowance.
                     *
                     * Requirements:
                     *
                     * - `spender` cannot be the zero address.
                     * - `spender` must have allowance for the caller of at least
                     * `subtractedValue`.
                     */
                    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                        _approve(
                            msg.sender,
                            spender,
                            _allowances[msg.sender][spender].sub(subtractedValue, Errors.ERC20_DECREASED_ALLOWANCE_BELOW_ZERO)
                        );
                        return true;
                    }
                    /**
                     * @dev Moves tokens `amount` from `sender` to `recipient`.
                     *
                     * This is internal function is equivalent to {transfer}, and can be used to
                     * e.g. implement automatic token fees, slashing mechanisms, etc.
                     *
                     * Emits a {Transfer} event.
                     *
                     * Requirements:
                     *
                     * - `sender` cannot be the zero address.
                     * - `recipient` cannot be the zero address.
                     * - `sender` must have a balance of at least `amount`.
                     */
                    function _transfer(
                        address sender,
                        address recipient,
                        uint256 amount
                    ) internal virtual {
                        _require(sender != address(0), Errors.ERC20_TRANSFER_FROM_ZERO_ADDRESS);
                        _require(recipient != address(0), Errors.ERC20_TRANSFER_TO_ZERO_ADDRESS);
                        _beforeTokenTransfer(sender, recipient, amount);
                        _balances[sender] = _balances[sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_BALANCE);
                        _balances[recipient] = _balances[recipient].add(amount);
                        emit Transfer(sender, recipient, amount);
                    }
                    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
                     * the total supply.
                     *
                     * Emits a {Transfer} event with `from` set to the zero address.
                     *
                     * Requirements:
                     *
                     * - `to` cannot be the zero address.
                     */
                    function _mint(address account, uint256 amount) internal virtual {
                        _beforeTokenTransfer(address(0), account, amount);
                        _setTotalSupply(totalSupply().add(amount));
                        _balances[account] = _balances[account].add(amount);
                        emit Transfer(address(0), account, amount);
                    }
                    /**
                     * @dev Destroys `amount` tokens from `account`, reducing the
                     * total supply.
                     *
                     * Emits a {Transfer} event with `to` set to the zero address.
                     *
                     * Requirements:
                     *
                     * - `account` cannot be the zero address.
                     * - `account` must have at least `amount` tokens.
                     */
                    function _burn(address account, uint256 amount) internal virtual {
                        _require(account != address(0), Errors.ERC20_BURN_FROM_ZERO_ADDRESS);
                        _beforeTokenTransfer(account, address(0), amount);
                        _balances[account] = _balances[account].sub(amount, Errors.ERC20_BURN_EXCEEDS_BALANCE);
                        _setTotalSupply(totalSupply().sub(amount));
                        emit Transfer(account, address(0), amount);
                    }
                    /**
                     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
                     *
                     * This internal function is equivalent to `approve`, and can be used to
                     * e.g. set automatic allowances for certain subsystems, etc.
                     *
                     * Emits an {Approval} event.
                     *
                     * Requirements:
                     *
                     * - `owner` cannot be the zero address.
                     * - `spender` cannot be the zero address.
                     */
                    function _approve(
                        address owner,
                        address spender,
                        uint256 amount
                    ) internal virtual {
                        _allowances[owner][spender] = amount;
                        emit Approval(owner, spender, amount);
                    }
                    /**
                     * @dev Sets {decimals} to a value other than the default one of 18.
                     *
                     * WARNING: This function should only be called from the constructor. Most
                     * applications that interact with token contracts will not expect
                     * {decimals} to ever change, and may work incorrectly if it does.
                     */
                    function _setupDecimals(uint8 decimals_) internal {
                        _decimals = decimals_;
                    }
                    /**
                     * @dev Hook that is called before any transfer of tokens. This includes
                     * minting and burning.
                     *
                     * Calling conditions:
                     *
                     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                     * will be to transferred to `to`.
                     * - when `from` is zero, `amount` tokens will be minted for `to`.
                     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
                     * - `from` and `to` are never both zero.
                     *
                     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                     */
                    function _beforeTokenTransfer(
                        address from,
                        address to,
                        uint256 amount
                    ) internal virtual {
                        // solhint-disable-previous-line no-empty-blocks
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20Permit.sol";
                import "./ERC20.sol";
                import "../helpers/EOASignaturesValidator.sol";
                /**
                 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
                 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
                 *
                 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
                 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
                 * need to send a transaction, and thus is not required to hold Ether at all.
                 *
                 * _Available since v3.4._
                 */
                abstract contract ERC20Permit is ERC20, IERC20Permit, EOASignaturesValidator {
                    // solhint-disable-next-line var-name-mixedcase
                    bytes32 private constant _PERMIT_TYPEHASH = keccak256(
                        "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                    );
                    /**
                     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
                     *
                     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
                     */
                    constructor(string memory name) EIP712(name, "1") {
                        // solhint-disable-previous-line no-empty-blocks
                    }
                    /**
                     * @dev See {IERC20Permit-permit}.
                     */
                    function permit(
                        address owner,
                        address spender,
                        uint256 value,
                        uint256 deadline,
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) public virtual override {
                        bytes32 structHash = keccak256(
                            abi.encode(_PERMIT_TYPEHASH, owner, spender, value, getNextNonce(owner), deadline)
                        );
                        _ensureValidSignature(owner, structHash, _toArraySignature(v, r, s), deadline, Errors.INVALID_SIGNATURE);
                        _approve(owner, spender, value);
                    }
                    /**
                     * @dev See {IERC20Permit-nonces}.
                     */
                    function nonces(address owner) public view override returns (uint256) {
                        return getNextNonce(owner);
                    }
                    /**
                     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
                     */
                    // solhint-disable-next-line func-name-mixedcase
                    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
                        return getDomainSeparator();
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the ReentrancyGuard library from OpenZeppelin Contracts, altered to reduce bytecode size.
                // Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
                // private functions, we achieve the same end result with slightly higher runtime gas costs, but reduced bytecode size.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Contract module that helps prevent reentrant calls to a function.
                 *
                 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
                 * available, which can be applied to functions to make sure there are no nested
                 * (reentrant) calls to them.
                 *
                 * Note that because there is a single `nonReentrant` guard, functions marked as
                 * `nonReentrant` may not call one another. This can be worked around by making
                 * those functions `private`, and then adding `external` `nonReentrant` entry
                 * points to them.
                 *
                 * TIP: If you would like to learn more about reentrancy and alternative ways
                 * to protect against it, check out our blog post
                 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
                 */
                abstract contract ReentrancyGuard {
                    // Booleans are more expensive than uint256 or any type that takes up a full
                    // word because each write operation emits an extra SLOAD to first read the
                    // slot's contents, replace the bits taken up by the boolean, and then write
                    // back. This is the compiler's defense against contract upgrades and
                    // pointer aliasing, and it cannot be disabled.
                    // The values being non-zero value makes deployment a bit more expensive,
                    // but in exchange the refund on every call to nonReentrant will be lower in
                    // amount. Since refunds are capped to a percentage of the total
                    // transaction's gas, it is best to keep them low in cases like this one, to
                    // increase the likelihood of the full refund coming into effect.
                    uint256 private constant _NOT_ENTERED = 1;
                    uint256 private constant _ENTERED = 2;
                    uint256 private _status;
                    constructor() {
                        _status = _NOT_ENTERED;
                    }
                    /**
                     * @dev Prevents a contract from calling itself, directly or indirectly.
                     * Calling a `nonReentrant` function from another `nonReentrant`
                     * function is not supported. It is possible to prevent this from happening
                     * by making the `nonReentrant` function external, and make it call a
                     * `private` function that does the actual work.
                     */
                    modifier nonReentrant() {
                        _enterNonReentrant();
                        _;
                        _exitNonReentrant();
                    }
                    function _enterNonReentrant() private {
                        // On the first call to nonReentrant, _status will be _NOT_ENTERED
                        _require(_status != _ENTERED, Errors.REENTRANCY);
                        // Any calls to nonReentrant after this point will fail
                        _status = _ENTERED;
                    }
                    function _exitNonReentrant() private {
                        // By storing the original value once again, a refund is triggered (see
                        // https://eips.ethereum.org/EIPS/eip-2200)
                        _status = _NOT_ENTERED;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
                 * checks.
                 *
                 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
                 * easily result in undesired exploitation or bugs, since developers usually
                 * assume that overflows raise errors. `SafeCast` restores this intuition by
                 * reverting the transaction when such an operation overflows.
                 *
                 * Using this library instead of the unchecked operations eliminates an entire
                 * class of bugs, so it's recommended to use it always.
                 *
                 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
                 * all math on `uint256` and `int256` and then downcasting.
                 */
                library SafeCast {
                    /**
                     * @dev Converts an unsigned uint256 into a signed int256.
                     *
                     * Requirements:
                     *
                     * - input must be less than or equal to maxInt256.
                     */
                    function toInt256(uint256 value) internal pure returns (int256) {
                        _require(value >> 255 == 0, Errors.SAFE_CAST_VALUE_CANT_FIT_INT256);
                        return int256(value);
                    }
                    /**
                     * @dev Converts an unsigned uint256 into an unsigned uint64.
                     *
                     * Requirements:
                     *
                     * - input must be less than or equal to maxUint64.
                     */
                    function toUint64(uint256 value) internal pure returns (uint64) {
                        _require(value <= type(uint64).max, Errors.SAFE_CAST_VALUE_CANT_FIT_UINT64);
                        return uint64(value);
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Wrappers over Solidity's arithmetic operations with added overflow
                 * checks.
                 *
                 * Arithmetic operations in Solidity wrap on overflow. This can easily result
                 * in bugs, because programmers usually assume that an overflow raises an
                 * error, which is the standard behavior in high level programming languages.
                 * `SafeMath` restores this intuition by reverting the transaction when an
                 * operation overflows.
                 *
                 * Using this library instead of the unchecked operations eliminates an entire
                 * class of bugs, so it's recommended to use it always.
                 */
                library SafeMath {
                    /**
                     * @dev Returns the addition of two unsigned integers, reverting on
                     * overflow.
                     *
                     * Counterpart to Solidity's `+` operator.
                     *
                     * Requirements:
                     *
                     * - Addition cannot overflow.
                     */
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a + b;
                        _require(c >= a, Errors.ADD_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the subtraction of two unsigned integers, reverting on
                     * overflow (when the result is negative).
                     *
                     * Counterpart to Solidity's `-` operator.
                     *
                     * Requirements:
                     *
                     * - Subtraction cannot overflow.
                     */
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        return sub(a, b, Errors.SUB_OVERFLOW);
                    }
                    /**
                     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                     * overflow (when the result is negative).
                     *
                     * Counterpart to Solidity's `-` operator.
                     *
                     * Requirements:
                     *
                     * - Subtraction cannot overflow.
                     */
                    function sub(
                        uint256 a,
                        uint256 b,
                        uint256 errorCode
                    ) internal pure returns (uint256) {
                        _require(b <= a, errorCode);
                        uint256 c = a - b;
                        return c;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                interface AggregatorV3Interface {
                  function decimals() external view returns (uint8);
                  function description() external view returns (string memory);
                  function version() external view returns (uint256);
                  // getRoundData and latestRoundData should both raise "No data present"
                  // if they do not have data to report, instead of returning unset values
                  // which could be misinterpreted as actual reported values.
                  function getRoundData(uint80 _roundId)
                    external
                    view
                    returns (
                      uint80 roundId,
                      int256 answer,
                      uint256 startedAt,
                      uint256 updatedAt,
                      uint80 answeredInRound
                    );
                  function latestRoundData()
                    external
                    view
                    returns (
                      uint80 roundId,
                      int256 answer,
                      uint256 startedAt,
                      uint256 updatedAt,
                      uint80 answeredInRound
                    );
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                library SwaapV2Errors {
                    // Safeguard Pool
                    uint256 internal constant EXCEEDED_SWAP_AMOUNT_IN = 0;
                    uint256 internal constant EXCEEDED_SWAP_AMOUNT_OUT = 1;
                    uint256 internal constant UNFAIR_PRICE = 2;
                    uint256 internal constant LOW_PERFORMANCE = 3;
                    uint256 internal constant MIN_BALANCE_OUT_NOT_MET = 4;
                    uint256 internal constant NOT_ENOUGH_PT_OUT = 5;
                    uint256 internal constant EXCEEDED_BURNED_PT = 6;
                    uint256 internal constant SIGNER_CANNOT_BE_NULL_ADDRESS = 7;
                    uint256 internal constant PERFORMANCE_UPDATE_INTERVAL_TOO_LOW = 8;
                    uint256 internal constant PERFORMANCE_UPDATE_INTERVAL_TOO_HIGH = 9;
                    uint256 internal constant MAX_PERFORMANCE_DEV_TOO_LOW = 10;
                    uint256 internal constant MAX_PERFORMANCE_DEV_TOO_HIGH = 11;
                    uint256 internal constant MAX_TARGET_DEV_TOO_LOW = 12;
                    uint256 internal constant MAX_TARGET_DEV_TOO_LARGE = 13;
                    uint256 internal constant MAX_PRICE_DEV_TOO_LOW = 14;
                    uint256 internal constant MAX_PRICE_DEV_TOO_LARGE = 15;
                    uint256 internal constant PERFORMANCE_UPDATE_TOO_SOON = 16;
                    uint256 internal constant BITMAP_SIGNATURE_NOT_VALID = 17;
                    uint256 internal constant QUOTE_ALREADY_USED = 18;
                    uint256 internal constant REPLAYABLE_SIGNATURE_NOT_VALID = 19;
                    uint256 internal constant QUOTE_BALANCE_NO_LONGER_VALID = 20;
                    uint256 internal constant WRONG_TOKEN_IN_IN_EXCESS = 21;
                    uint256 internal constant WRONG_TOKEN_OUT_IN_EXCESS = 22;
                    uint256 internal constant EXCEEDS_TIMEOUT = 23;
                    uint256 internal constant NON_POSITIVE_PRICE = 24;
                    uint256 internal constant FEES_TOO_HIGH = 25;
                    uint256 internal constant LOW_INITIAL_BALANCE = 26;
                    uint256 internal constant ORACLE_TIMEOUT_TOO_HIGH = 27;
                    uint256 internal constant OUTDATED_ORACLE_ROUND_ID = 28;
                    uint256 internal constant LOW_SWAP_AMOUNT_IN = 29;
                    uint256 internal constant LOW_SWAP_AMOUNT_OUT = 30;
                    uint256 internal constant PAUSED = 31;
                    uint256 internal constant INVALID_AGGREGATOR = 32;
                    uint256 internal constant PASSED_DEADLINE = 33;
                    uint256 internal constant SAME_TOKENS = 34;
                    uint256 internal constant INVALID_DATA_LENGTH = 35;
                }
                /**
                * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 99 are
                * supported.
                */
                function _srequire(bool condition, uint256 errorCode) pure {
                    if (!condition) _srevert(errorCode);
                }
                /**
                 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 99 are supported.
                 */
                function _srevert(uint256 errorCode) pure {
                    // We're going to dynamically create a revert uint256 based on the error code, with the following format:
                    // 'SWAAP#{errorCode}'
                    // where the code is left-padded with zeroes to two digits (so they range from 00 to 99).
                    //
                    // We don't have revert uint256s embedded in the contract to save bytecode size: it takes much less space to store a
                    // number (8 to 16 bits) than the individual uint256 characters.
                    //
                    // The dynamic uint256 creation algorithm that follows could be implemented in Solidity, but assembly allows for a
                    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
                    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
                    assembly {
                        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-99
                        // range, so we only need to convert two digits. To convert the digits to ASCII, we add 0x30, the value for
                        // the '0' character.
                        let units := add(mod(errorCode, 10), 0x30)
                        errorCode := div(errorCode, 10)
                        let tenths := add(mod(errorCode, 10), 0x30)
                        // With the individual characters, we can now construct the full uint256. The SWAAP# part is a known constant
                        // (0x535741415023): we simply shift this by 16 (to provide space for the 2 bytes of the error code), and add
                        // the characters to it, each shifted by a multiple of 8.
                        // The revert reason is then shifted left by 192 bits (256 minus the length of the uint256, 8 characters * 8
                        // bits per character = 64) to locate it in the most significant part of the 256 slot (the beginning of a byte
                        // array).
                        let revertReason := shl(192, add(0x5357414150230000, add(units, shl(8, tenths))))
                        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
                        // message will have the following layout:
                        // [ revert reason identifier ] [ uint256 location offset ] [ uint256 length ] [ uint256 contents ]
                        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(uint256) function. We
                        // also write zeroes to the next 29 bytes of memory, but those are about to be overwritten.
                        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
                        // Next is the offset to the location of the uint256, which will be placed immediately after (20 bytes away).
                        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
                        // The uint256 length is fixed: 8 characters.
                        mstore(0x24, 8)
                        // Finally, the uint256 itself is stored.
                        mstore(0x44, revertReason)
                        // Even if the uint256 is only 8 bytes long, we need to return a full 32 byte slot containing it. The length of
                        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
                        revert(0, 100)
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@chainlink/contracts/src/v0.7/interfaces/AggregatorV3Interface.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IBasePool.sol";
                import "./ISignatureSafeguard.sol";
                interface ISafeguardPool is IBasePool, ISignatureSafeguard {
                    event PegStatesUpdated(bool isPegged0, bool isPegged1);
                    event FlexibleOracleStatesUpdated(bool isFlexibleOracle0, bool isFlexibleOracle1);
                    event SignerChanged(address indexed signer);
                    event MustAllowlistLPsSet(bool mustAllowlistLPs);
                    event PerfUpdateIntervalChanged(uint256 perfUpdateInterval);
                    event MaxPerfDevChanged(uint256 maxPerfDev);
                    event MaxTargetDevChanged(uint256 maxTargetDev);
                    event MaxPriceDevChanged(uint256 maxPriceDev);
                    event ManagementFeesUpdated(uint256 yearlyFees);
                    /// @dev the amountIn and amountOut are denominated in 18-decimals,
                    /// irrespective of the specific decimal precision utilized by each token.
                    event Quote(bytes32 indexed digest, uint256 amountIn18Decimals, uint256 amountOut18Decimals);
                    
                    /// @dev The target balances are denominated in 18-decimals,
                    /// irrespective of the specific decimal precision utilized by each token.
                    event InitialTargetBalancesSet(uint256 targetBalancePerPT0, uint256 targetBalancePerPT1);
                    /// @param feesClaimed corresponds to the minted pool tokens
                    /// @param totalSupply corresponds to the total supply before minting the pool tokens
                    event ManagementFeesClaimed(uint256 feesClaimed, uint256 totalSupply, uint256 yearlyRate, uint256 time);
                    
                    /// @dev The target balances are denominated in 18-decimals,
                    /// irrespective of the specific decimal precision utilized by each token.
                    event PerformanceUpdated(
                        uint256 targetBalancePerPT0,
                        uint256 targetBalancePerPT1,
                        uint256 performance,
                        uint256 amount0Per1,
                        uint256 time
                    );
                    
                    struct InitialSafeguardParams {
                        address signer; // address that signs the quotes
                        uint256 maxPerfDev; // maximum performance deviation
                        uint256 maxTargetDev; // maximum balance deviation from hodl benchmark
                        uint256 maxPriceDev; // maximum price deviation
                        uint256 perfUpdateInterval; // performance update interval
                        uint256 yearlyFees; // management fees in yearly %
                        bool    mustAllowlistLPs; // must use allowlist flag
                    }
                    struct InitialOracleParams {
                        AggregatorV3Interface oracle;
                        uint256 maxTimeout;
                        bool isStable;
                        bool isFlexibleOracle;
                    }
                    struct OracleParams {
                        AggregatorV3Interface oracle;
                        uint256 maxTimeout;
                        bool isStable;
                        bool isFlexibleOracle;
                        bool isPegged;
                        uint256 priceScalingFactor;
                    }
                    /*
                    * Setters
                    */
                    
                    /// @dev sets or removes flexible oracles
                    function setFlexibleOracleStates(bool isFlexibleOracle0, bool isFlexibleOracle1) external;
                    /// @dev sets or removes allowlist 
                    function setMustAllowlistLPs(bool mustAllowlistLPs) external;
                    /// @dev sets the quote signer
                    function setSigner(address signer) external;
                    /// @dev sets the performance update interval
                    function setPerfUpdateInterval(uint256 perfUpdateInterval) external;
                    /// @dev sets the max performance deviation
                    function setMaxPerfDev(uint256 maxPerfDev) external;
                    /// @dev sets the maximum deviation from target balances
                    function setMaxTargetDev(uint256 maxTargetDev) external;
                    /// @dev sets the maximum quote price deviation from the oracles
                    function setMaxPriceDev(uint256 maxPriceDev) external;
                    /// @dev sets yearly management fees
                    function setManagementFees(uint256 yearlyFees) external;
                    /// @dev updates the performance and the hodl balances (should be permissionless)
                    function updatePerformance() external;
                    /// @dev unpegs or repegs oracles based on the latest prices (should be permissionless)
                    function evaluateStablesPegStates() external;
                    /// @dev claims accumulated management fees (can be permissionless)
                    function claimManagementFees() external;
                    /*
                    * Getters
                    */
                    /// @dev returns the current pool's performance
                    function getPoolPerformance() external view returns(uint256);
                    
                    /// @dev returns if the pool 
                    function isAllowlistEnabled() external view returns(bool);
                    
                    /// @dev returns the current target balances of the pool based on the hodl strategy and latest performance
                    function getHodlBalancesPerPT() external view returns(uint256, uint256);
                    
                    /// @dev returns the on-chain oracle price of tokenIn such that price = amountIn / amountOut
                    function getOnChainAmountInPerOut(address tokenIn) external view returns(uint256);
                    
                    /// @dev returns the current pool's safeguard parameters
                    function getPoolParameters() external view returns(
                        uint256 maxPerfDev,
                        uint256 maxTargetDev,
                        uint256 maxPriceDev,
                        uint256 lastPerfUpdate,
                        uint256 perfUpdateInterval
                    );
                    
                    /// @dev returns the current pool oracle parameters
                    function getOracleParams() external view returns(OracleParams[] memory);
                    /// @dev returns the yearly fees, yearly rate and the latest fee claim time
                    function getManagementFeesParams() external view returns(uint256, uint256, uint256);
                }// SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                interface ISignatureSafeguard {
                    event AllowlistJoinSignatureValidated(bytes32 indexed digest);
                    /// @dev returns quote signer's address
                    function signer() external returns(address); 
                    /// @dev returns the bitmap word value given the word's index (= index / 256)
                    function getQuoteBitmapWord(uint256 wordIndex) external view returns(uint);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./ISafeguardPool.sol";
                library SafeguardPoolUserData {
                    // In order to preserve backwards compatibility, make sure new join and exit kinds are added at the end of the enum.
                    enum JoinKind { INIT, ALL_TOKENS_IN_FOR_EXACT_BPT_OUT, EXACT_TOKENS_IN_FOR_BPT_OUT }
                    enum ExitKind { EXACT_BPT_IN_FOR_TOKENS_OUT, BPT_IN_FOR_EXACT_TOKENS_OUT }
                    uint256 private constant _MASK_128_BITS = 0x00000000000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF;
                    uint256 private constant _OFFSET_128_BITS = 128;
                    function joinKind(bytes memory self) internal pure returns (JoinKind) {
                        return abi.decode(self, (JoinKind));
                    }
                    function exitKind(bytes memory self) internal pure returns (ExitKind) {
                        return abi.decode(self, (ExitKind));
                    }
                    // Swaps
                    
                    function pricingParameters(bytes memory self) internal pure
                    returns(
                        address expectedOrigin,
                        uint256 originBasedSlippage,
                        bytes32 priceBasedParams,
                        bytes32 quoteBalances,
                        uint256 quoteTotalSupply,
                        bytes32 balanceBasedParams,
                        bytes32 timeBasedParams
                    ) {
                        return abi.decode(self, (address, uint256, bytes32, bytes32, uint256, bytes32, bytes32));
                    }
                    function decodeSignedSwapData(bytes calldata self) internal pure 
                    returns(bytes memory swapData, bytes memory signature, uint256 quoteIndex, uint256 deadline) {
                        (
                            swapData,
                            signature,
                            quoteIndex,
                            deadline
                        ) = abi.decode(self, (bytes, bytes, uint256, uint256));
                    }
                    function unpackPairedUints(bytes32 packedUint) internal pure returns(uint256 a, uint256 b) {
                        assembly{
                            a := shr(_OFFSET_128_BITS, packedUint)
                            b := and(_MASK_128_BITS, packedUint)
                        }
                    }
                    // Joins
                    function allowlistData(bytes memory self) internal pure
                    returns (uint256 deadline, bytes memory signature, bytes memory joinData) {
                        (deadline, signature, joinData) = abi.decode(self, (uint256, bytes, bytes));
                    }
                    function initJoin(bytes memory self) internal pure returns (JoinKind kind, uint256[] memory amountsIn) {
                        (kind, amountsIn) = abi.decode(self, (JoinKind, uint256[]));
                    }
                    function allTokensInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut) {
                        (, bptAmountOut) = abi.decode(self, (JoinKind, uint256));
                    }
                    // Exits
                    function exactBptInForTokensOut(bytes memory self) internal pure returns (uint256 bptAmountIn) {
                        (, bptAmountIn) = abi.decode(self, (ExitKind, uint256));
                    }
                    function decodeSignedExitData(bytes memory self) internal pure 
                    returns(ExitKind kind, uint256 deadline, bytes memory exitData, bytes memory signature){
                        (
                            kind,
                            deadline,
                            exitData,
                            signature
                        ) = abi.decode(self, (ExitKind, uint256, bytes, bytes));
                    }
                    // Join/Exit + Swap
                    function exactJoinExitSwapData(bytes memory self) internal pure 
                    returns (bool swapTokenIn, bytes memory swapData, bytes memory signature, uint256 quoteIndex, uint256 deadline){
                        (
                            , // corresponds to join or exit kind
                            , // minBptAmountOut or maxBptAmountIn
                            , // join amountsIn or exit amounts Out
                            swapTokenIn, // excess token in or limit token in
                            swapData, // swap pricing data
                            signature, // the signature based on swapData & other quote pricing information
                            quoteIndex, // the index of the quote
                            deadline // swap deadline
                        ) = abi.decode(self, (uint8, uint, uint[], bool, bytes, bytes, uint256, uint256));
                    }
                    // Join/Exit + Swap
                    function exactJoinExitAmountsData(bytes memory self) internal pure 
                    returns (uint256 limitBptAmount, uint256[] memory joinExitAmounts) {
                        
                        (
                            , // corresponds to join or exit kind
                            limitBptAmount, // minBptAmountOut or maxBptAmountIn
                            joinExitAmounts // join amountsIn or exit amounts Out
                        ) = abi.decode(self, (uint8, uint, uint[]));
                    }
                }// SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU Affero General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
                // GNU Affero General Public License for more details.
                // You should have received a copy of the GNU Affero General Public License
                // along with this program. If not, see <http://www.gnu.org/licenses/>.
                pragma solidity =0.7.6;
                pragma experimental ABIEncoderV2;
                import "@chainlink/contracts/src/v0.7/interfaces/AggregatorV3Interface.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "@swaap-labs/v2-errors/contracts/SwaapV2Errors.sol";
                library ChainlinkUtils {
                    function getLatestPrice(AggregatorV3Interface oracle, uint256 maxTimeout) internal view returns (uint256) {
                        (
                            uint80 roundId, int256 latestPrice, , uint256 latestTimestamp, uint80 answeredInRound
                        ) = AggregatorV3Interface(oracle).latestRoundData();
                        // we assume that block.timestamp >= maxTimeout
                        _srequire(latestTimestamp >= block.timestamp - maxTimeout, SwaapV2Errors.EXCEEDS_TIMEOUT);
                        _srequire(latestPrice > 0, SwaapV2Errors.NON_POSITIVE_PRICE);
                        _srequire(roundId == answeredInRound, SwaapV2Errors.OUTDATED_ORACLE_ROUND_ID);
                        return uint256(latestPrice);
                    }
                    function computePriceScalingFactor(AggregatorV3Interface oracle) internal view returns (uint256) {
                        // Oracles that don't implement the `decimals` method are not supported.
                        uint256 oracleDecimals = oracle.decimals();
                        // Oracles with more than 18 decimals are not supported.
                        uint256 decimalsDifference = Math.sub(18, oracleDecimals);
                        return FixedPoint.ONE * 10**decimalsDifference;
                    }
                }// SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity =0.7.6;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/LogExpMath.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeCast.sol";
                import "@swaap-labs/v2-errors/contracts/SwaapV2Errors.sol";
                library SafeguardMath {
                    using FixedPoint for uint256;
                    using SafeCast for uint256;
                    uint256 private constant _ONE_YEAR = 365 days;
                    /**
                    * @notice slippage based on the lag between quotation and execution time
                    */
                    function calcTimeBasedPenalty(
                        uint256 currentTimestamp,
                        uint256 startTime,
                        uint256 timeBasedSlippage
                    ) internal pure returns(uint256) {
                        if(currentTimestamp <= startTime) {
                            return 0;
                        }
                        return Math.mul(timeBasedSlippage, (currentTimestamp - startTime));
                    }
                    /**
                    * @notice slippage based on the change of the pool's balance between quotation and execution time
                    * @param balanceTokenIn actual balance of the token in before the swap
                    * @param balanceTokenOut actual balance of the token out before the swap
                    * @param totalSupply total supply of the pool during swap time
                    * @param quoteBalanceIn expected balance of the token in at the time of the quote
                    * @param quoteBalanceOut expected balance of the token out at the time of the quote
                    * @param quoteTotalSupply expected total supply of the pool at the time of the quote
                    * @param balanceChangeTolerance max percentage change of the pool's balance between quotation and execution
                    * @param balanceBasedSlippage slope based on the change of the pool's balance between quotation and execution
                    */
                    function calcBalanceBasedPenalty(
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut,
                        uint256 totalSupply,
                        uint256 quoteBalanceIn,
                        uint256 quoteBalanceOut,
                        uint256 quoteTotalSupply,
                        uint256 balanceChangeTolerance,
                        uint256 balanceBasedSlippage
                    ) internal pure returns (uint256) {
                        
                        // if the expected balance of the token in is lower than the actual balance, we apply a penalty
                        uint256 balanceDevIn = Math.max(
                            calcBalanceDeviation(balanceTokenIn, quoteBalanceIn),
                            calcBalanceDeviation(balanceTokenIn.divDown(totalSupply), quoteBalanceIn.divDown(quoteTotalSupply))
                        );
                        // if the expected balance of the token out is lower than the actual balance, we apply a penalty
                        uint256 balanceDevOut = Math.max(
                            calcBalanceDeviation(balanceTokenOut, quoteBalanceOut),
                            calcBalanceDeviation(balanceTokenOut.divDown(totalSupply), quoteBalanceOut.divDown(quoteTotalSupply))
                        );
                        uint256 maxDeviation = Math.max(balanceDevIn, balanceDevOut);
                        _srequire(maxDeviation <= balanceChangeTolerance, SwaapV2Errors.QUOTE_BALANCE_NO_LONGER_VALID);
                        return balanceBasedSlippage.mulUp(maxDeviation);
                    }
                    function calcBalanceDeviation(uint256 currentBalance, uint256 quoteBalance) internal pure returns(uint256) {
                        return currentBalance >= quoteBalance ? 0 : (quoteBalance - currentBalance).divDown(quoteBalance);
                    }
                    /**
                    * @notice slippage based on the transaction origin
                    */
                    function calcOriginBasedPenalty(
                        address expectedOrigin,
                        uint256 originBasedSlippage
                    ) internal view returns(uint256) {
                 
                        if(expectedOrigin != tx.origin) {
                            return originBasedSlippage;
                        }
                        return 0;
                    }
                    /**********************************************************************************************
                    // aE = amountIn in excess                                                                   //
                    // aL = limiting amountIn                                                                    //
                    // bE = current balance of excess token                  /       aE * bL - aL * bE       \\   //
                    // bL = current balance of limiting token         sIn = | ------------------------------- |  //
                    // sIn = swap amount in needed before the join           \\ bL + aL + (1/p) * ( bE + aE ) /   //
                    // sOut = swap amount out needed before the join                                             //
                    // p = relative price such that: sIn = p * sOut                                              //
                    **********************************************************************************************/
                    function calcJoinSwapAmounts(
                        uint256 excessTokenBalance,
                        uint256 limitTokenBalance,
                        uint256 excessTokenAmountIn,
                        uint256 limitTokenAmountIn,
                        uint256 quoteAmountInPerOut
                    ) internal pure returns (uint256, uint256) {
                        uint256 foo = excessTokenAmountIn.mulDown(limitTokenBalance);
                        uint256 bar = limitTokenAmountIn.mulDown(excessTokenBalance);
                        _srequire(foo >= bar, SwaapV2Errors.WRONG_TOKEN_IN_IN_EXCESS);
                        uint256 num = foo - bar;
                        uint256 denom = limitTokenBalance.add(limitTokenAmountIn);
                        denom = denom.add((excessTokenBalance.add(excessTokenAmountIn)).divDown(quoteAmountInPerOut));
                        uint256 swapAmountIn = num.divDown(denom);
                        uint256 swapAmountOut = swapAmountIn.divDown(quoteAmountInPerOut);
                        return (swapAmountIn, swapAmountOut);
                    }
                    /**********************************************************************************************
                    // aE = amountIn in excess                                                                   //
                    // bE = current balance of excess token                        / aE - sIn  \\                 //
                    // sIn = swap amount in needed before the join         rOpt = | ----------- |                //
                    // rOpt = amountIn TV / current pool TVL                       \\ bE + sIn  /                 //
                    **********************************************************************************************/
                    function calcJoinSwapROpt(
                        uint256 excessTokenBalance,
                        uint256 excessTokenAmountIn,
                        uint256 swapAmountIn
                    ) internal pure returns (uint256) {
                        uint256 num   = excessTokenAmountIn.sub(swapAmountIn);
                        uint256 denom = excessTokenBalance.add(swapAmountIn);
                        // removing 1wei from the numerator and adding 1wei to the denominator to make up for rounding errors
                        // that may have accumulated in previous calculations
                        return (num.sub(1)).divDown(denom.add(1));
                    }
                    /**********************************************************************************************
                    // aE = amountOut in excess                                                                  //
                    // aL = limiting amountOut                                                                   //
                    // bE = current balance of excess token                   /     aE * bL - aL * bE     \\      //
                    // bL = current balance of limiting token         sOut = | --------------------------- |     //
                    // sIn = swap amount in needed before the exit            \\ bL - aL + p * ( bE - aE ) /      //
                    // sOut = swap amount out needed before the exit                                             //
                    // p = relative price such that: sIn = p * sOut                                              //
                    **********************************************************************************************/
                    function calcExitSwapAmounts(
                        uint256 excessTokenBalance,
                        uint256 limitTokenBalance,
                        uint256 excessTokenAmountOut,
                        uint256 limitTokenAmountOut,
                        uint256 quoteAmountInPerOut
                    ) internal pure returns (uint256, uint256) {
                        uint256 foo = excessTokenAmountOut.mulDown(limitTokenBalance);
                        uint256 bar = limitTokenAmountOut.mulDown(excessTokenBalance);
                        _srequire(foo >= bar, SwaapV2Errors.WRONG_TOKEN_OUT_IN_EXCESS);
                        uint256 num = foo - bar;
                        uint256 denom = limitTokenBalance.sub(limitTokenAmountOut);
                        denom = denom.add((excessTokenBalance.sub(excessTokenAmountOut)).mulDown(quoteAmountInPerOut));
                        uint256 swapAmountOut = num.divDown(denom);
                        uint256 swapAmountIn = quoteAmountInPerOut.mulDown(swapAmountOut);
                        return (swapAmountIn, swapAmountOut);
                    }
                    /**********************************************************************************************
                    // aE = amountOut in excess                                                                  //
                    // bE = current balance of excess token                        / aE - sOut  \\                //
                    // sOut = swap amount out needed before the exit       rOpt = | ----------- |                //
                    // rOpt = amountOut TV / current pool TVL                      \\ bE - sOut  /                //
                    **********************************************************************************************/
                    function calcExitSwapROpt(
                        uint256 excessTokenBalance,
                        uint256 excessTokenAmountOut,
                        uint256 swapAmountOut
                    ) internal pure returns (uint256) {
                        uint256 num   = excessTokenAmountOut.sub(swapAmountOut);
                        uint256 denom = excessTokenBalance.sub(swapAmountOut);
                        
                        // adding 1wei to the numerator and removing 1wei from the denominator to make up for rounding errors
                        // that may have accumulated in previous calculations
                        return (num.add(1)).divDown(denom.sub(1));
                    }
                    /**********************************************************************************************
                    // f = yearly management fees percentage          /  ln(1 - f) \\                             //
                    // 1y = 1 year                             a = - | ------------ |                            //
                    // a = yearly rate constant                       \\     1y     /                             //
                    **********************************************************************************************/
                    function calcYearlyRate(uint256 yearlyFees) internal pure returns(uint256) {
                        uint256 logInput = FixedPoint.ONE.sub(yearlyFees);
                        // Since 0 < logInput <= 1 => logResult <= 0
                        int256 logResult = LogExpMath.ln(int256(logInput));
                        return(uint256(-logResult) / _ONE_YEAR);
                    }
                    /**********************************************************************************************
                    // bptOut = bpt tokens to be minted as fees                                                  //
                    // TS = total supply                                   bptOut = TS * (e^(a*dT) -1)           //
                    // a = yearly rate constant                                                                  //
                    // dT = elapsed time between the previous and current claim                                  //
                    **********************************************************************************************/
                    function calcAccumulatedManagementFees(
                        uint256 elapsedTime,
                        uint256 yearlyRate,
                        uint256 currentSupply
                     ) internal pure returns(uint256) {
                        uint256 expInput = Math.mul(yearlyRate, elapsedTime);
                        uint256 expResult = uint256(LogExpMath.exp(expInput.toInt256()));
                        return (currentSupply.mulDown(expResult.sub(FixedPoint.ONE)));
                    }
                }// SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                /*
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                                                         7W@█
                */
                pragma solidity =0.7.6;
                pragma experimental ABIEncoderV2;
                import "./ChainlinkUtils.sol";
                import "./SafeguardMath.sol";
                import "./SignatureSafeguard.sol";
                import "@balancer-labs/v2-pool-utils/contracts/BasePool.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IMinimalSwapInfoPool.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/EOASignaturesValidator.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-pool-utils/contracts/lib/BasePoolMath.sol";
                import "@swaap-labs/v2-interfaces/contracts/safeguard-pool/SafeguardPoolUserData.sol";
                import "@swaap-labs/v2-interfaces/contracts/safeguard-pool/ISafeguardPool.sol";
                import "@swaap-labs/v2-errors/contracts/SwaapV2Errors.sol";
                /**
                 * @title Safeguard Pool
                 * @author Swaap-labs (https://github.com/swaap-labs/swaap-v2-monorepo)
                 * @notice Main contract that allows the use of a non-custodial RfQ market-making infrastructure that
                 * implements safety measures (i.e "safeguards") to prevent potential value extraction from the pool.
                 * For more details: https://www.swaap.finance/v2-whitepaper.pdf.
                 * @dev This contract is built on top of Balancer V2's infrastructure but is meant to be deployed with
                 * a modified version of Balancer V2 Vault. (refer to the comments in the `updatePerformance` function
                 * for more details).
                 */
                contract SafeguardPool is ISafeguardPool, SignatureSafeguard, BasePool, IMinimalSwapInfoPool, ReentrancyGuard {
                    using FixedPoint for uint256;
                    using WordCodec for bytes32;
                    using BasePoolUserData for bytes;
                    using SafeguardPoolUserData for bytes32;
                    using SafeguardPoolUserData for bytes;
                    uint256 private constant _NUM_TOKENS = 2;
                    
                    // initial BPT minted at the initialization of the pool
                    uint256 private constant _INITIAL_BPT = 100 ether;
                    // minimum acceptable balance at the initialization of the pool (balance upscaled to 18 decimals)
                    uint256 private constant _MIN_INITIAL_BALANCE = 1e8;
                    // Pool parameters constants
                    uint256 private constant _MIN_SWAP_AMOUNT_PERCENTAGE = 10e16; // 10% min swap amount
                    uint256 private constant _MAX_PERFORMANCE_DEVIATION = 90e16; // 10% max tolerance
                    uint256 private constant _MAX_TARGET_DEVIATION = 0; // 100% max tolerance
                    uint256 private constant _MAX_PRICE_DEVIATION = 97e16; // 3% max tolerance
                    uint256 private constant _MIN_PERFORMANCE_UPDATE_INTERVAL = 0.5 days;
                    uint256 private constant _MAX_PERFORMANCE_UPDATE_INTERVAL = 1.5 days;
                    uint256 private constant _MAX_ORACLE_TIMEOUT = 1.5 days;
                    uint256 private constant _MAX_YEARLY_FEES = 20e16; // corresponds to 20% of yearly fees
                    IERC20 internal immutable _token0;
                    IERC20 internal immutable _token1;
                    
                    AggregatorV3Interface internal immutable _oracle0;
                    AggregatorV3Interface internal immutable _oracle1;
                    uint256 internal immutable _maxOracleTimeout0;
                    uint256 internal immutable _maxOracleTimeout1;
                    bool internal immutable _isStable0;
                    bool internal immutable _isStable1;
                    uint256 internal constant _REPEG_PRICE_BOUND = 0.002e18; // repegs at 0.2%
                    uint256 internal constant _UNPEG_PRICE_BOUND = 0.005e18; // unpegs at 0.5%
                    // tokens scale factor
                    uint256 internal immutable _scaleFactor0;
                    uint256 internal immutable _scaleFactor1;
                    // oracle price scale factor
                    uint256 internal immutable _priceScaleFactor0;
                    uint256 internal immutable _priceScaleFactor1;
                    // quote signer
                    address private _signer;
                    // Allowlist enabled / disabled
                    bool private _mustAllowlistLPs;
                    // Management fees related variables
                    uint32 private _previousClaimTime;
                    // yearly rate for management fees
                    uint56 private _yearlyRate;
                    // yearly management fees
                    uint64 private _yearlyFees;
                    // solhint-disable max-line-length
                    // [ isPegged0 | isPegged1 | flexibleOracle0 | flexibleOracle1 | max performance dev | max hodl dev | max price dev | perf update interval | last perf update ]
                    // [   1 bit   |   1 bit   |      1 bit      |      1 bit      |       60 bits       |    64 bits   |    64 bits    |        32 bits       |      32 bits     ]
                    // [ MSB                                                                                                                                                  LSB ]
                    bytes32 private _packedPoolParams;
                    // solhint-enable max-line-length
                    // used to determine if stable coin is holding the peg
                    uint256 private constant _TOKEN_0_PEGGED_BIT_OFFSET = 255;
                    uint256 private constant _TOKEN_1_PEGGED_BIT_OFFSET = 254;
                    // used to determine if the oracle can be pegged to a fixed value
                    uint256 private constant _FLEXIBLE_ORACLE_0_BIT_OFFSET = 253;
                    uint256 private constant _FLEXIBLE_ORACLE_1_BIT_OFFSET = 252;
                    // used to determine if the pool is underperforming compared to the last performance update
                    uint256 private constant _MAX_PERF_DEV_BIT_OFFSET = 192;
                    uint256 private constant _MAX_PERF_DEV_BIT_LENGTH = 60;
                    // used to determine if the pool balances deviated from the hodl reference
                    uint256 private constant _MAX_TARGET_DEV_BIT_OFFSET = 128;
                    uint256 private constant _MAX_TARGET_DEV_BIT_LENGTH = 64;
                    // used to determine if the quote's price is too low compared to the oracle's price
                    uint256 private constant _MAX_PRICE_DEV_BIT_OFFSET = 64;
                    uint256 private constant _MAX_PRICE_DEV_BIT_LENGTH = 64;
                    // used to determine if a performance update is needed before a swap / one-asset-join / one-asset-exit
                    uint256 private constant _PERF_UPDATE_INTERVAL_BIT_OFFSET = 32;
                    uint256 private constant _PERF_LAST_UPDATE_BIT_OFFSET = 0;
                    uint256 private constant _PERF_TIME_BIT_LENGTH = 32;
                    
                    // [ min balance 0 per PT | min balance 1 per PT ]
                    // [       128 bits       |       128 bits       ]
                    // [ MSB                                     LSB ]
                    bytes32 private _hodlBalancesPerPT; // benchmark target reserves based on performance
                    uint256 private constant _HODL_BALANCE_BIT_OFFSET_0 = 128;
                    uint256 private constant _HODL_BALANCE_BIT_OFFSET_1 = 0;
                    uint256 private constant _HODL_BALANCE_BIT_LENGTH   = 128;
                    constructor(
                        IVault vault,
                        string memory name,
                        string memory symbol,
                        IERC20[] memory tokens,
                        address[] memory assetManagers,
                        uint256 pauseWindowDuration,
                        uint256 bufferPeriodDuration,
                        address owner,
                        InitialOracleParams[] memory oracleParams,
                        InitialSafeguardParams memory safeguardParameters
                    )
                        BasePool(
                            vault,
                            IVault.PoolSpecialization.TWO_TOKEN,
                            name,
                            symbol,
                            tokens,
                            assetManagers,
                            _getMinSwapFeePercentage(),
                            pauseWindowDuration,
                            bufferPeriodDuration,
                            owner
                        )
                    {
                        InputHelpers.ensureInputLengthMatch(tokens.length, _NUM_TOKENS);
                        InputHelpers.ensureInputLengthMatch(oracleParams.length, _NUM_TOKENS);
                        // token related parameters
                        _token0 = IERC20(address(tokens[0]));
                        _token1 = IERC20(address(tokens[1]));
                        _scaleFactor0 = _computeScalingFactor(tokens[0]);
                        _scaleFactor1 = _computeScalingFactor(tokens[1]);
                        // oracle related parameters
                        _oracle0 = oracleParams[0].oracle;
                        _oracle1 = oracleParams[1].oracle;
                        // oracles max price timeouts must be lower than 1.5 days
                        _srequire(
                            oracleParams[0].maxTimeout <= _MAX_ORACLE_TIMEOUT && oracleParams[1].maxTimeout <= _MAX_ORACLE_TIMEOUT,
                            SwaapV2Errors.ORACLE_TIMEOUT_TOO_HIGH
                        );
                        // setting oracles price max timeouts
                        _maxOracleTimeout0 = oracleParams[0].maxTimeout;
                        _maxOracleTimeout1 = oracleParams[1].maxTimeout;
                        // setting oracles price scale factors
                        _priceScaleFactor0 = ChainlinkUtils.computePriceScalingFactor(oracleParams[0].oracle);
                        _priceScaleFactor1 = ChainlinkUtils.computePriceScalingFactor(oracleParams[1].oracle);
                        _isStable0 = oracleParams[0].isStable;
                        _isStable1 = oracleParams[1].isStable;
                        if(oracleParams[0].isStable && oracleParams[0].isFlexibleOracle) {
                            _packedPoolParams = _packedPoolParams.insertBool(true, _FLEXIBLE_ORACLE_0_BIT_OFFSET);
                        }
                        if(oracleParams[1].isStable && oracleParams[1].isFlexibleOracle) {
                            _packedPoolParams = _packedPoolParams.insertBool(true, _FLEXIBLE_ORACLE_1_BIT_OFFSET);
                        }
                        // pool related parameters
                        _setSigner(safeguardParameters.signer);
                        _setMaxPerfDev(safeguardParameters.maxPerfDev);
                        _setMaxTargetDev(safeguardParameters.maxTargetDev);
                        _setMaxPriceDev(safeguardParameters.maxPriceDev);
                        _setPerfUpdateInterval(safeguardParameters.perfUpdateInterval);
                        _previousClaimTime = uint32(block.timestamp); // _previousClaimTime is not updated in _setYearlyRate
                        _setYearlyRate(safeguardParameters.yearlyFees);
                        _setMustAllowlistLPs(safeguardParameters.mustAllowlistLPs);
                    }
                    function onSwap(
                        SwapRequest calldata request,
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut
                    ) external override onlyVault(request.poolId) returns (uint256) {
                        _beforeSwapJoinExit();
                        bool isTokenInToken0 = request.tokenIn == _token0;
                        (bytes memory swapData, bytes32 digest) = _swapSignatureSafeguard(
                            request.kind,
                            isTokenInToken0,
                            request.from,
                            request.to,
                            request.userData
                        );
                        
                        (uint256 scalingFactorTokenIn, uint256 scalingFactorTokenOut) = _scalingFactorsInAndOut(isTokenInToken0);
                        balanceTokenIn = _upscale(balanceTokenIn, scalingFactorTokenIn);
                        balanceTokenOut = _upscale(balanceTokenOut, scalingFactorTokenOut);
                        (uint256 quoteAmountInPerOut, uint256 maxSwapAmount) = 
                            _getQuoteAmountInPerOut(swapData, balanceTokenIn, balanceTokenOut);
                        if (request.kind == IVault.SwapKind.GIVEN_IN) {
                            uint256 amountIn = request.amount;
                            return _onSwapGivenIn(
                                digest,
                                isTokenInToken0,
                                balanceTokenIn,
                                balanceTokenOut,
                                amountIn,
                                quoteAmountInPerOut,
                                maxSwapAmount,
                                scalingFactorTokenIn,
                                scalingFactorTokenOut
                            );
                        } else {
                            uint256 amountOut = request.amount;
                            return _onSwapGivenOut(
                                digest,
                                isTokenInToken0,
                                balanceTokenIn,
                                balanceTokenOut,
                                amountOut,
                                quoteAmountInPerOut,
                                maxSwapAmount,
                                scalingFactorTokenIn,
                                scalingFactorTokenOut
                            );
                        }
                    }
                    /// @dev amountInPerOut = baseAmountInPerOut * (1 + slippagePenalty)
                    function _getQuoteAmountInPerOut(
                        bytes memory swapData,
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut
                    ) internal view returns (uint256, uint256) {
                        
                        (
                            address expectedOrigin,
                            uint256 originBasedSlippage,
                            bytes32 priceBasedParams,
                            bytes32 quoteBalances,
                            uint256 quoteTotalSupply,
                            bytes32 balanceBasedParams,
                            bytes32 timeBasedParams
                        ) = swapData.pricingParameters();
                        
                        uint256 penalty = _getBalanceBasedPenalty(
                            balanceTokenIn,
                            balanceTokenOut,
                            quoteBalances,
                            quoteTotalSupply,
                            balanceBasedParams
                        );
                        
                        penalty = penalty.add(_getTimeBasedPenalty(timeBasedParams));
                        penalty = penalty.add(SafeguardMath.calcOriginBasedPenalty(expectedOrigin, originBasedSlippage));
                        (uint256 quoteAmountInPerOut, uint256 maxSwapAmount) = priceBasedParams.unpackPairedUints();
                        penalty = penalty.add(FixedPoint.ONE);
                        return (quoteAmountInPerOut.mulUp(penalty), maxSwapAmount);
                    }
                    function _getBalanceBasedPenalty(
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut,
                        bytes32 quoteBalances,
                        uint256 quoteTotalSupply,
                        bytes32 balanceBasedParams
                    ) internal view returns(uint256) 
                    {
                        (uint256 quoteBalanceIn, uint256 quoteBalanceOut) = quoteBalances.unpackPairedUints();
                        (uint256 balanceChangeTolerance, uint256 balanceBasedSlippage) 
                            = balanceBasedParams.unpackPairedUints();
                        return SafeguardMath.calcBalanceBasedPenalty(
                            balanceTokenIn,
                            balanceTokenOut,
                            totalSupply(),
                            quoteBalanceIn,
                            quoteBalanceOut,
                            quoteTotalSupply,
                            balanceChangeTolerance,
                            balanceBasedSlippage
                        );
                    }
                    function _getTimeBasedPenalty(bytes32 timeBasedParams) internal view returns(uint256) {
                        (uint256 startTime, uint256 timeBasedSlippage) = timeBasedParams.unpackPairedUints();
                        return SafeguardMath.calcTimeBasedPenalty(block.timestamp, startTime, timeBasedSlippage);
                    }
                    function _onSwapGivenIn(
                        bytes32 digest,
                        bool    isTokenInToken0,
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut,
                        uint256 amountIn,
                        uint256 quoteAmountInPerOut,
                        uint256 maxSwapAmount,
                        uint256 scalingFactorTokenIn,
                        uint256 scalingFactorTokenOut
                    ) internal returns(uint256) {
                        amountIn = _upscale(amountIn, scalingFactorTokenIn);
                        uint256 amountOut = amountIn.divDown(quoteAmountInPerOut);
                        _validateSwap(
                            digest,
                            IVault.SwapKind.GIVEN_IN,
                            isTokenInToken0,
                            balanceTokenIn,
                            balanceTokenOut,
                            amountIn,
                            amountOut,
                            quoteAmountInPerOut,
                            maxSwapAmount
                        );
                        return _downscaleDown(amountOut, scalingFactorTokenOut);
                    }
                    function _onSwapGivenOut(
                        bytes32 digest,
                        bool    isTokenInToken0,
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut,
                        uint256 amountOut,
                        uint256 quoteAmountInPerOut,
                        uint256 maxSwapAmount,
                        uint256 scalingFactorTokenIn,
                        uint256 scalingFactorTokenOut
                    ) internal returns(uint256) {
                        amountOut = _upscale(amountOut, scalingFactorTokenOut);
                        uint256 amountIn = amountOut.mulUp(quoteAmountInPerOut);
                        _validateSwap(
                            digest,
                            IVault.SwapKind.GIVEN_OUT,
                            isTokenInToken0,
                            balanceTokenIn,
                            balanceTokenOut,
                            amountIn,
                            amountOut,
                            quoteAmountInPerOut,
                            maxSwapAmount
                        );
                        return _downscaleUp(amountIn, scalingFactorTokenIn);
                    }
                    /**
                    * @dev all the inputs should be normalized to 18 decimals regardless of token decimals
                    */
                    function _validateSwap(
                        bytes32 digest,
                        IVault.SwapKind kind,
                        bool    isTokenInToken0,
                        uint256 balanceTokenIn,
                        uint256 balanceTokenOut,
                        uint256 amountIn,
                        uint256 amountOut,
                        uint256 quoteAmountInPerOut,
                        uint256 maxSwapAmount
                    ) internal {
                        if(kind == IVault.SwapKind.GIVEN_IN) {
                            _srequire(amountIn <= maxSwapAmount, SwaapV2Errors.EXCEEDED_SWAP_AMOUNT_IN);
                            _srequire(amountIn >= maxSwapAmount.mulDown(_MIN_SWAP_AMOUNT_PERCENTAGE), SwaapV2Errors.LOW_SWAP_AMOUNT_IN);
                        } else {
                            _srequire(amountOut <= maxSwapAmount, SwaapV2Errors.EXCEEDED_SWAP_AMOUNT_OUT);
                            _srequire(amountOut >= maxSwapAmount.mulDown(_MIN_SWAP_AMOUNT_PERCENTAGE), SwaapV2Errors.LOW_SWAP_AMOUNT_OUT);
                        }
                        bytes32 packedPoolParams = _packedPoolParams;
                        uint256 onChainAmountInPerOut = _getOnChainAmountInPerOut(packedPoolParams, isTokenInToken0);
                        _fairPricingSafeguard(quoteAmountInPerOut, onChainAmountInPerOut, packedPoolParams);
                        uint256 totalSupply = totalSupply();
                        _updatePerformanceIfDue(
                            isTokenInToken0,
                            balanceTokenIn,
                            balanceTokenOut,
                            onChainAmountInPerOut,
                            totalSupply,
                            packedPoolParams
                        );
                        _balancesSafeguard(
                            isTokenInToken0,
                            balanceTokenIn.add(amountIn),
                            balanceTokenOut.sub(amountOut),
                            onChainAmountInPerOut,
                            totalSupply,
                            packedPoolParams
                        );
                        Quote(digest, amountIn, amountOut);
                    }
                    // ensures that the quote has a fair price compared to the on-chain price
                    function _fairPricingSafeguard(
                        uint256 quoteAmountInPerOut,
                        uint256 onChainAmountInPerOut,
                        bytes32 packedPoolParams
                    ) internal pure {
                        _srequire(quoteAmountInPerOut.divDown(onChainAmountInPerOut) >= _getMaxPriceDev(packedPoolParams), SwaapV2Errors.UNFAIR_PRICE);
                    }
                    // updates the pool target balances based on performance if needed
                    function _updatePerformanceIfDue(
                        bool    isTokenInToken0,
                        uint256 currentBalanceIn,
                        uint256 currentBalanceOut,
                        uint256 onChainAmountInPerOut,
                        uint256 totalSupply,
                        bytes32 packedPoolParams
                    ) internal {
                        (uint256 lastPerfUpdate, uint256 perfUpdateInterval) = _getPerformanceTimeParams(packedPoolParams);
                        // lastPerfUpdate & perfUpdateInterval are stored in 32 bits so they cannot overflow
                        if(block.timestamp > lastPerfUpdate + perfUpdateInterval){
                            if(isTokenInToken0){
                                _updatePerformance(currentBalanceIn, currentBalanceOut, onChainAmountInPerOut, totalSupply);
                            } else {
                                _updatePerformance(
                                    currentBalanceOut,
                                    currentBalanceIn,
                                    FixedPoint.ONE.divDown(onChainAmountInPerOut),
                                    totalSupply
                                );
                            }
                        }
                    }
                    function _balancesSafeguard(
                        bool    isTokenInToken0,
                        uint256 newBalanceIn,
                        uint256 newBalanceOut,
                        uint256 onChainAmountInPerOut,
                        uint256 totalSupply,
                        bytes32 packedPoolParams
                    ) internal view {
                        (uint256 newBalancePerPTIn, uint256 newBalancePerPTOut, uint256 hodlBalancePerPTIn, uint256 hodlBalancePerPTOut) 
                            = _getBalancesPerPT(isTokenInToken0, newBalanceIn, newBalanceOut, totalSupply);
                        
                        // we check for performance only if the pool is not being rebalanced by the current swap
                        if (newBalancePerPTOut < hodlBalancePerPTOut || newBalancePerPTIn > hodlBalancePerPTIn) {
                            _srequire(
                                _getPerfFromBalancesPerPT(
                                    newBalancePerPTIn,
                                    newBalancePerPTOut,
                                    hodlBalancePerPTIn,
                                    hodlBalancePerPTOut,
                                    onChainAmountInPerOut
                                ) >= _getMaxPerfDev(packedPoolParams), 
                                SwaapV2Errors.LOW_PERFORMANCE
                            );
                        }
                        _srequire(
                            newBalancePerPTOut.divDown(hodlBalancePerPTOut) >= _getMaxTargetDev(packedPoolParams), 
                            SwaapV2Errors.MIN_BALANCE_OUT_NOT_MET
                        );
                    }
                    function _onInitializePool(
                        bytes32, // poolId,
                        address sender,
                        address, // recipient,
                        uint256[] memory scalingFactors,
                        bytes memory userData
                    ) internal override returns (uint256, uint256[] memory) {
                        if(isAllowlistEnabled()) {
                            userData = _isLPAllowed(sender, userData);
                        }
                        (SafeguardPoolUserData.JoinKind kind, uint256[] memory amountsIn) = userData.initJoin();
                        
                        _require(kind == SafeguardPoolUserData.JoinKind.INIT, Errors.UNINITIALIZED);
                        _require(amountsIn.length == _NUM_TOKENS, Errors.TOKENS_LENGTH_MUST_BE_2);
                        
                        _upscaleArray(amountsIn, scalingFactors);
                        // prevents the pool from being initialized with a low balance (i.e. amountIn = 1 wei)
                        // which will result in an usuable pool at initialization since hodlBalancePerPT will be equal to 0 
                        // and targeDeviation = currentBalancePerPT / hodlBalancePerPT (illegal division by 0)
                        _srequire(
                            amountsIn[0] >= _MIN_INITIAL_BALANCE && amountsIn[1] >= _MIN_INITIAL_BALANCE,
                            SwaapV2Errors.LOW_INITIAL_BALANCE
                        );
                        // sets initial target balances
                        uint256 initHodlBalancePerPT0 = amountsIn[0].divDown(_INITIAL_BPT);
                        uint256 initHodlBalancePerPT1 = amountsIn[1].divDown(_INITIAL_BPT);
                        _setHodlBalancesPerPT(initHodlBalancePerPT0, initHodlBalancePerPT1);
                        emit InitialTargetBalancesSet(initHodlBalancePerPT0, initHodlBalancePerPT1);
                        
                        return (_INITIAL_BPT, amountsIn);
                        
                    }
                    function _onJoinPool(
                        bytes32, // poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256, // lastChangeBlock,
                        uint256, // protocolSwapFeePercentage,
                        uint256[] memory, // scalingFactors,
                        bytes memory userData
                    ) internal override returns (uint256 bptAmountOut, uint256[] memory amountsIn) {
                        _beforeJoinExit();
                        if(isAllowlistEnabled()) {
                            userData = _isLPAllowed(sender, userData);
                        }
                        SafeguardPoolUserData.JoinKind kind = userData.joinKind();
                        if(kind == SafeguardPoolUserData.JoinKind.ALL_TOKENS_IN_FOR_EXACT_BPT_OUT) {
                            return _joinAllTokensInForExactBPTOut(balances, totalSupply(), userData);
                        } else if (kind == SafeguardPoolUserData.JoinKind.EXACT_TOKENS_IN_FOR_BPT_OUT) {
                            return _joinExactTokensInForBPTOut(sender, recipient, balances, userData);
                        } else {
                            _revert(Errors.UNHANDLED_JOIN_KIND);
                        }
                    }
                    function _isLPAllowed(address sender, bytes memory userData) internal returns(bytes memory) {
                        // we subtiture userData by the joinData
                        return _validateAllowlistSignature(sender, userData);
                    }
                    function _joinAllTokensInForExactBPTOut(
                        uint256[] memory balances,
                        uint256 totalSupply,
                        bytes memory userData
                    ) private  pure returns (uint256, uint256[] memory) {
                              
                        uint256 bptAmountOut = userData.allTokensInForExactBptOut();
                        // Note that there is no maximum amountsIn parameter: this is handled by `IVault.joinPool`.
                        uint256[] memory amountsIn = BasePoolMath.computeProportionalAmountsIn(balances, totalSupply, bptAmountOut);
                        return (bptAmountOut, amountsIn);
                    }
                    function _joinExactTokensInForBPTOut(
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        bytes memory userData
                    ) internal returns (uint256, uint256[] memory) {
                        (
                            uint256 minBptAmountOut,
                            uint256[] memory joinAmounts,
                            bool isExcessToken0,
                            ValidatedQuoteData memory validatedQuoteData
                        ) = _joinExitSwapSignatureSafeguard(sender, recipient, userData);
                        (uint256 excessTokenBalance, uint256 limitTokenBalance) = isExcessToken0?
                            (balances[0], balances[1]) : (balances[1], balances[0]);
                        (uint256 quoteAmountInPerOut, uint256 maxSwapAmount) = _getQuoteAmountInPerOut(validatedQuoteData.swapData, excessTokenBalance, limitTokenBalance);
                        
                        (uint256 excessTokenAmountIn, uint256 limitTokenAmountIn) = isExcessToken0?
                            (joinAmounts[0], joinAmounts[1]) : (joinAmounts[1], joinAmounts[0]);
                        
                        (
                            uint256 swapAmountIn,
                            uint256 swapAmountOut
                        ) = SafeguardMath.calcJoinSwapAmounts(
                            excessTokenBalance,
                            limitTokenBalance,
                            excessTokenAmountIn,
                            limitTokenAmountIn,
                            quoteAmountInPerOut
                        );
                        _validateSwap(
                            validatedQuoteData.digest,
                            IVault.SwapKind.GIVEN_IN,
                            isExcessToken0,
                            excessTokenBalance,
                            limitTokenBalance,
                            swapAmountIn,
                            swapAmountOut,
                            quoteAmountInPerOut,
                            maxSwapAmount
                        );
                        uint256 rOpt = SafeguardMath.calcJoinSwapROpt(excessTokenBalance, excessTokenAmountIn, swapAmountIn);
                        
                        uint256 bptAmountOut = totalSupply().mulDown(rOpt);        
                        _srequire(bptAmountOut >= minBptAmountOut, SwaapV2Errors.NOT_ENOUGH_PT_OUT);
                        
                        return (bptAmountOut, joinAmounts);
                    }
                    function _doRecoveryModeExit(
                        uint256[] memory balances,
                        uint256 totalSupply,
                        bytes memory userData
                    ) internal pure override returns (uint256 bptAmountIn, uint256[] memory amountsOut) {
                        bptAmountIn = userData.recoveryModeExit();
                        amountsOut = BasePoolMath.computeProportionalAmountsOut(balances, totalSupply, bptAmountIn);
                    }
                    function _onExitPool(
                        bytes32, // poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256, // lastChangeBlock,
                        uint256, // protocolSwapFeePercentage,
                        uint256[] memory, // scalingFactors,
                        bytes memory userData
                    ) internal override returns (uint256 bptAmountIn, uint256[] memory amountsOut) {
                        _beforeJoinExit();
                        (SafeguardPoolUserData.ExitKind kind) = userData.exitKind();
                        if(kind == SafeguardPoolUserData.ExitKind.EXACT_BPT_IN_FOR_TOKENS_OUT) {
                            return _exitExactBPTInForTokensOut(balances, totalSupply(), userData);
                        } else if (kind == SafeguardPoolUserData.ExitKind.BPT_IN_FOR_EXACT_TOKENS_OUT) {
                            
                            return _exitBPTInForExactTokensOut(sender, recipient, balances, userData);
                        } else {
                            _revert(Errors.UNHANDLED_EXIT_KIND);
                        }
                    }
                    function _exitExactBPTInForTokensOut(
                        uint256[] memory balances,
                        uint256 totalSupply,
                        bytes memory userData
                    ) private returns (uint256, uint256[] memory) {
                               
                        // updates pool performance if necessary
                        try this.updatePerformance() {} catch {}
                        
                        uint256 bptAmountIn = userData.exactBptInForTokensOut();
                        // Note that there is no minimum amountOut parameter: this is handled by `IVault.exitPool`.
                        uint256[] memory amountsOut = BasePoolMath.computeProportionalAmountsOut(balances, totalSupply, bptAmountIn);
                        return (bptAmountIn, amountsOut);
                    }
                    function _exitBPTInForExactTokensOut(
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        bytes memory userData
                    ) internal returns (uint256, uint256[] memory) {
                        
                        (
                            uint256 maxBptAmountIn,
                            uint256[] memory exitAmounts,
                            bool isLimitToken0,
                            ValidatedQuoteData memory validatedQuoteData
                        ) = _joinExitSwapSignatureSafeguard(sender, recipient, userData);
                        (uint256 excessTokenBalance, uint256 limitTokenBalance) = isLimitToken0?
                            (balances[1], balances[0]) : (balances[0], balances[1]);
                        (uint256 quoteAmountInPerOut, uint256 maxSwapAmount) = _getQuoteAmountInPerOut(validatedQuoteData.swapData, limitTokenBalance, excessTokenBalance);
                        (uint256 excessTokenAmountOut, uint256 limitTokenAmountOut) = isLimitToken0?
                            (exitAmounts[1], exitAmounts[0]) : (exitAmounts[0], exitAmounts[1]);
                        (
                            uint256 swapAmountIn,
                            uint256 swapAmountOut
                        ) = SafeguardMath.calcExitSwapAmounts(
                            excessTokenBalance,
                            limitTokenBalance,
                            excessTokenAmountOut,
                            limitTokenAmountOut,
                            quoteAmountInPerOut
                        );
                        _validateSwap(
                            validatedQuoteData.digest,
                            IVault.SwapKind.GIVEN_IN,
                            isLimitToken0,
                            limitTokenBalance,
                            excessTokenBalance,
                            swapAmountIn,
                            swapAmountOut,
                            quoteAmountInPerOut,
                            maxSwapAmount
                        );
                        uint256 rOpt = SafeguardMath.calcExitSwapROpt(excessTokenBalance, excessTokenAmountOut, swapAmountOut);
                                
                        uint256 bptAmountIn = totalSupply().mulUp(rOpt);
                        
                        _srequire(bptAmountIn <= maxBptAmountIn, SwaapV2Errors.EXCEEDED_BURNED_PT);
                        
                        return (bptAmountIn, exitAmounts);
                    }
                    /**
                    * Setters
                    */
                    /// @inheritdoc ISafeguardPool
                    function setFlexibleOracleStates(
                        bool isFlexibleOracle0,
                        bool isFlexibleOracle1
                    ) external override authenticate whenNotPaused {
                       
                        bytes32 packedPoolParams = _packedPoolParams;
                        if(_isStable0) {
                            if(!isFlexibleOracle0) {
                                // if the oracle is no longer flexible we need to reset the peg state
                                packedPoolParams = packedPoolParams.insertBool(false, _TOKEN_0_PEGGED_BIT_OFFSET);
                            }
                            packedPoolParams = packedPoolParams.insertBool(isFlexibleOracle0, _FLEXIBLE_ORACLE_0_BIT_OFFSET);
                        }
                        if(_isStable1) {
                            if(!isFlexibleOracle1) {
                                // if the oracle is no longer flexible we need to reset the peg state
                                packedPoolParams = packedPoolParams.insertBool(false, _TOKEN_1_PEGGED_BIT_OFFSET);
                            }
                            packedPoolParams = packedPoolParams.insertBool(isFlexibleOracle1, _FLEXIBLE_ORACLE_1_BIT_OFFSET);
                        }
                        _packedPoolParams = packedPoolParams;
                        // we do not use the inputs of the function because they may not me update the state if the token isn't stable
                        emit FlexibleOracleStatesUpdated(_isFlexibleOracle0(packedPoolParams), _isFlexibleOracle1(packedPoolParams));
                    }
                    /// @inheritdoc ISafeguardPool
                    function setMustAllowlistLPs(bool mustAllowlistLPs) external override authenticate whenNotPaused {
                        _setMustAllowlistLPs(mustAllowlistLPs);
                    }
                    function _setMustAllowlistLPs(bool mustAllowlistLPs) private {
                        _mustAllowlistLPs = mustAllowlistLPs;
                        emit MustAllowlistLPsSet(mustAllowlistLPs);
                    }
                    /// @inheritdoc ISafeguardPool
                    function setSigner(address signer_) external override authenticate whenNotPaused {
                        _setSigner(signer_);
                    }
                    function _setSigner(address signer_) internal {
                        _srequire(signer_ != address(0), SwaapV2Errors.SIGNER_CANNOT_BE_NULL_ADDRESS);
                        _signer = signer_;
                        emit SignerChanged(signer_);
                    }
                    /// @inheritdoc ISafeguardPool
                    function setPerfUpdateInterval(uint256 perfUpdateInterval) external override authenticate whenNotPaused {
                        _setPerfUpdateInterval(perfUpdateInterval);
                    }
                    function _setPerfUpdateInterval(uint256 perfUpdateInterval) internal {
                        _srequire(perfUpdateInterval >= _MIN_PERFORMANCE_UPDATE_INTERVAL, SwaapV2Errors.PERFORMANCE_UPDATE_INTERVAL_TOO_LOW);
                        _srequire(perfUpdateInterval <= _MAX_PERFORMANCE_UPDATE_INTERVAL, SwaapV2Errors.PERFORMANCE_UPDATE_INTERVAL_TOO_HIGH);
                        _packedPoolParams = _packedPoolParams.insertUint(
                            perfUpdateInterval,
                            _PERF_UPDATE_INTERVAL_BIT_OFFSET,
                            _PERF_TIME_BIT_LENGTH
                        );
                        emit PerfUpdateIntervalChanged(perfUpdateInterval);
                    }    
                    
                    /// @inheritdoc ISafeguardPool
                    function setMaxPerfDev(uint256 maxPerfDev) external override authenticate whenNotPaused {
                        _setMaxPerfDev(maxPerfDev);
                    }
                    /// @dev for gas optimization purposes we store (1 - max tolerance)
                    function _setMaxPerfDev(uint256 maxPerfDev) internal {
                        
                        // the lower maxPerfDev value is, the less strict the performance check is (more permitted deviation)
                        _srequire(maxPerfDev <= FixedPoint.ONE, SwaapV2Errors.MAX_PERFORMANCE_DEV_TOO_LOW);
                        _srequire(maxPerfDev >= _MAX_PERFORMANCE_DEVIATION, SwaapV2Errors.MAX_PERFORMANCE_DEV_TOO_HIGH);
                        
                        _packedPoolParams = _packedPoolParams.insertUint(
                            maxPerfDev,
                            _MAX_PERF_DEV_BIT_OFFSET,
                            _MAX_PERF_DEV_BIT_LENGTH
                        );
                        emit MaxPerfDevChanged(maxPerfDev);
                    }
                    /// @inheritdoc ISafeguardPool
                    function setMaxTargetDev(uint256 maxTargetDev) external override authenticate whenNotPaused {
                        _setMaxTargetDev(maxTargetDev);
                    }
                    
                    /// @dev for gas optimization purposes we store (1 - max tolerance)
                    function _setMaxTargetDev(uint256 maxTargetDev) internal {
                        // the lower maxTargetDev value is, the less strict the balances check is (more permitted deviation)  
                        _srequire(maxTargetDev <= FixedPoint.ONE, SwaapV2Errors.MAX_TARGET_DEV_TOO_LOW);
                        _srequire(maxTargetDev >= _MAX_TARGET_DEVIATION, SwaapV2Errors.MAX_TARGET_DEV_TOO_LARGE);
                        
                        _packedPoolParams = _packedPoolParams.insertUint(
                            maxTargetDev,
                            _MAX_TARGET_DEV_BIT_OFFSET,
                            _MAX_TARGET_DEV_BIT_LENGTH
                        );
                        emit MaxTargetDevChanged(maxTargetDev);
                    }
                    /// @inheritdoc ISafeguardPool
                    function setMaxPriceDev(uint256 maxPriceDev) external override authenticate whenNotPaused {
                        _setMaxPriceDev(maxPriceDev);
                    }
                    /// @dev for gas optimization purposes we store (1 - max tolerance)
                    function _setMaxPriceDev(uint256 maxPriceDev) internal {
                        // the lower maxPriceDev value is, the less strict the price check is (more permitted deviation)  
                        _srequire(maxPriceDev <= FixedPoint.ONE, SwaapV2Errors.MAX_PRICE_DEV_TOO_LOW);
                        _srequire(maxPriceDev >= _MAX_PRICE_DEVIATION, SwaapV2Errors.MAX_PRICE_DEV_TOO_LARGE);
                        _packedPoolParams = _packedPoolParams.insertUint(
                            maxPriceDev,
                            _MAX_PRICE_DEV_BIT_OFFSET,
                            _MAX_PRICE_DEV_BIT_LENGTH
                        );
                        emit MaxPriceDevChanged(maxPriceDev);
                    }
                    /**
                     * @dev This function assumes that the pool is deployed with a modified version of the vault
                     * that addresses a known reentrancy issue described here:
                     * https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345.
                     * The modified version of the vault is available here:
                     * https://github.com/swaap-labs/swaap-v2-monorepo/commit/85e0ef66b460995129f196be42762186b3d3727d
                     * If you're using an old version of the vault, you should add _ensureNotInVaultContext function
                     * https://github.com/balancer/balancer-v2-monorepo/pull/2418/files
                     * 
                    */
                    /// @inheritdoc ISafeguardPool
                    function updatePerformance() external override nonReentrant whenNotPaused {
                        bytes32 packedPoolParams = _packedPoolParams;
                        (uint256 lastPerfUpdate, uint256 perfUpdateInterval) = _getPerformanceTimeParams(packedPoolParams);
                        
                        _srequire(block.timestamp > lastPerfUpdate + perfUpdateInterval, SwaapV2Errors.PERFORMANCE_UPDATE_TOO_SOON);
                        (, uint256[] memory balances, ) = getVault().getPoolTokens(getPoolId());
                        _upscaleArray(balances, _scalingFactors());
                        uint256 amount0Per1 = _getOnChainAmountInPerOut(packedPoolParams, true);
                        _updatePerformance(balances[0], balances[1], amount0Per1, totalSupply()); 
                    }
                    function _updatePerformance(
                        uint256 balance0,
                        uint256 balance1,
                        uint256 amount0Per1,
                        uint256 totalSupply
                    ) private {
                        
                        uint256 currentTVLPerPT = (balance0.add(balance1.mulDown(amount0Per1))).divDown(totalSupply);
                        
                        (uint256 hodlBalancePerPT0, uint256 hodlBalancePerPT1) = getHodlBalancesPerPT();
                        
                        uint256 oldTVLPerPT = hodlBalancePerPT0.add(hodlBalancePerPT1.mulDown(amount0Per1));
                        
                        uint256 currentPerformance = currentTVLPerPT.divDown(oldTVLPerPT);
                        hodlBalancePerPT0 = hodlBalancePerPT0.mulDown(currentPerformance);
                        hodlBalancePerPT1 = hodlBalancePerPT1.mulDown(currentPerformance);
                        _setHodlBalancesPerPT(hodlBalancePerPT0, hodlBalancePerPT1);
                        emit PerformanceUpdated(hodlBalancePerPT0, hodlBalancePerPT1, currentPerformance, amount0Per1, block.timestamp);
                    }
                    function _setHodlBalancesPerPT(uint256 hodlBalancePerPT0, uint256 hodlBalancePerPT1) private {
                        
                        bytes32 hodlBalancesPerPT = WordCodec.encodeUint(
                                hodlBalancePerPT0,
                                _HODL_BALANCE_BIT_OFFSET_0,
                                _HODL_BALANCE_BIT_LENGTH
                        );
                        
                        hodlBalancesPerPT = hodlBalancesPerPT.insertUint(
                                hodlBalancePerPT1,
                                _HODL_BALANCE_BIT_OFFSET_1,
                                _HODL_BALANCE_BIT_LENGTH
                        );
                        _hodlBalancesPerPT = hodlBalancesPerPT;
                        _packedPoolParams = _packedPoolParams.insertUint(
                            block.timestamp,
                            _PERF_LAST_UPDATE_BIT_OFFSET,
                            _PERF_TIME_BIT_LENGTH
                        );
                    }
                    /// @inheritdoc ISafeguardPool
                    function evaluateStablesPegStates() external override nonReentrant whenNotPaused {
                        bytes32 packedPoolParams = _packedPoolParams;
                        
                        if(_isStable0 && _isFlexibleOracle0(packedPoolParams)) {
                            bool newPegState = _canBePegged(_isTokenPegged0(packedPoolParams), _oracle0, _maxOracleTimeout0, _priceScaleFactor0);
                            packedPoolParams = packedPoolParams.insertBool(newPegState, _TOKEN_0_PEGGED_BIT_OFFSET);
                        }
                        
                        if(_isStable1 && _isFlexibleOracle1(packedPoolParams)) {
                            bool newPegState = _canBePegged(_isTokenPegged1(packedPoolParams), _oracle1, _maxOracleTimeout1, _priceScaleFactor1);
                            packedPoolParams = packedPoolParams.insertBool(newPegState, _TOKEN_1_PEGGED_BIT_OFFSET);
                        }
                        _packedPoolParams = packedPoolParams;
                        emit PegStatesUpdated(_isTokenPegged0(packedPoolParams), _isTokenPegged1(packedPoolParams));
                    }
                    /**
                    * Getters
                    */
                    /// @inheritdoc ISafeguardPool
                    function getPoolPerformance() external view override returns(uint256 performance){
                        (, uint256[] memory balances, ) = getVault().getPoolTokens(getPoolId());
                        _upscaleArray(balances, _scalingFactors());
                        uint256 onChainAmountInPerOut = _getOnChainAmountInPerOut(_packedPoolParams, true);
                        performance = _getPerf(true, balances[0], balances[1], onChainAmountInPerOut, totalSupply());
                    }
                    function _getPerf(
                        bool    isTokenInToken0,
                        uint256 newBalanceIn,
                        uint256 newBalanceOut,
                        uint256 onChainAmountInPerOut,
                        uint256 totalSupply
                    ) internal view returns (uint256) {
                        
                        (uint256 newBalancePerPTIn, uint256 newBalancePerPTOut, uint256 hodlBalancePerPTIn, uint256 hodlBalancePerPTOut) = 
                            _getBalancesPerPT(isTokenInToken0, newBalanceIn, newBalanceOut, totalSupply);
                        
                        return _getPerfFromBalancesPerPT(
                            newBalancePerPTIn,
                            newBalancePerPTOut,
                            hodlBalancePerPTIn,
                            hodlBalancePerPTOut,
                            onChainAmountInPerOut
                        );
                    }
                    function _getPerfFromBalancesPerPT(
                        uint256 newBalancePerPTIn,
                        uint256 newBalancePerPTOut,
                        uint256 hodlBalancePerPTIn,
                        uint256 hodlBalancePerPTOut,
                        uint256 onChainAmountInPerOut
                    ) internal pure returns (uint256) {
                        uint256 newTVLPerPT = (newBalancePerPTIn.divDown(onChainAmountInPerOut)).add(newBalancePerPTOut);
                        uint256 oldTVLPerPT = (hodlBalancePerPTIn.divDown(onChainAmountInPerOut)).add(hodlBalancePerPTOut);
                        return newTVLPerPT.divDown(oldTVLPerPT);
                    }
                    function _getBalancesPerPT(
                        bool    isTokenInToken0,
                        uint256 newBalanceIn,
                        uint256 newBalanceOut,
                        uint256 totalSupply
                    ) internal view returns (uint256, uint256, uint256, uint256) {
                        (uint256 hodlBalancePerPT0, uint256 hodlBalancePerPT1) = getHodlBalancesPerPT();
                        (uint256 hodlBalancePerPTIn, uint256 hodlBalancePerPTOut) = isTokenInToken0?
                            (hodlBalancePerPT0, hodlBalancePerPT1) :
                            (hodlBalancePerPT1, hodlBalancePerPT0); 
                        uint256 newBalancePerPTIn = newBalanceIn.divDown(totalSupply);
                        uint256 newBalancePerPTOut = newBalanceOut.divDown(totalSupply);
                        return(newBalancePerPTIn, newBalancePerPTOut, hodlBalancePerPTIn, hodlBalancePerPTOut);
                    }
                    function _isTokenPegged0(bytes32 packedPoolParams) internal pure returns(bool){
                        return packedPoolParams.decodeBool(_TOKEN_0_PEGGED_BIT_OFFSET);
                    }
                    function _isTokenPegged1(bytes32 packedPoolParams) internal pure returns(bool){
                        return packedPoolParams.decodeBool(_TOKEN_1_PEGGED_BIT_OFFSET);
                    }
                    /// @inheritdoc ISafeguardPool
                    function isAllowlistEnabled() public view override returns(bool) {
                        return _mustAllowlistLPs;
                    }
                    /// @inheritdoc ISafeguardPool
                    function getHodlBalancesPerPT() public view override returns(uint256 hodlBalancePerPT0, uint256 hodlBalancePerPT1) {
                        
                        bytes32 hodlBalancesPerPT = _hodlBalancesPerPT;
                    
                        hodlBalancePerPT0 = hodlBalancesPerPT.decodeUint(
                                _HODL_BALANCE_BIT_OFFSET_0,
                                _HODL_BALANCE_BIT_LENGTH
                        );
                        
                        hodlBalancePerPT1 = hodlBalancesPerPT.decodeUint(
                                _HODL_BALANCE_BIT_OFFSET_1,
                                _HODL_BALANCE_BIT_LENGTH
                        );
                    
                    }
                    /// @inheritdoc ISafeguardPool
                    function getOnChainAmountInPerOut(address tokenIn) external view override returns(uint256) {
                        return _getOnChainAmountInPerOut(_packedPoolParams, IERC20(tokenIn) == _token0);
                    }
                    /**
                    * @notice returns the relative price such as: amountIn = relativePrice * amountOut
                    */
                    function _getOnChainAmountInPerOut(bytes32 packedPoolParams, bool isTokenInToken0)
                    internal view returns(uint256) {
                        
                        uint256 price0;
                        
                        if(_isStable0 && _isFlexibleOracle0(packedPoolParams) && _isTokenPegged0(packedPoolParams)) {
                            price0 = FixedPoint.ONE;
                        } else {
                            price0 = _getPriceFromOracle(_oracle0, _maxOracleTimeout0, _priceScaleFactor0);
                        }
                        uint256 price1;
                        
                        if(_isStable1 && _isFlexibleOracle1(packedPoolParams) && _isTokenPegged1(packedPoolParams)) {
                            price1 = FixedPoint.ONE;
                        } else {
                            price1 = _getPriceFromOracle(_oracle1, _maxOracleTimeout1, _priceScaleFactor1);
                        }
                       
                        return isTokenInToken0? price1.divDown(price0) : price0.divDown(price1); 
                    }
                    function _getPriceFromOracle(
                        AggregatorV3Interface oracle,
                        uint256 maxTimeout,
                        uint256 priceScaleFactor
                    ) internal view returns(uint256){
                        return  _upscale(ChainlinkUtils.getLatestPrice(oracle, maxTimeout), priceScaleFactor);
                    }
                    /// @inheritdoc ISafeguardPool
                    function getPoolParameters() external view override
                    returns (
                        uint256 maxPerfDev,
                        uint256 maxTargetDev,
                        uint256 maxPriceDev,
                        uint256 lastPerfUpdate,
                        uint256 perfUpdateInterval
                    ) {
                        bytes32 packedPoolParams = _packedPoolParams;
                        
                        maxPerfDev = _getMaxPerfDev(packedPoolParams);
                        maxTargetDev = _getMaxTargetDev(packedPoolParams);
                        
                        maxPriceDev = _getMaxPriceDev(packedPoolParams);
                        
                        (lastPerfUpdate, perfUpdateInterval) = _getPerformanceTimeParams(packedPoolParams);
                    }
                    function _isFlexibleOracle0(bytes32 packedPoolParams) internal pure returns(bool) {
                        return packedPoolParams.decodeBool(_FLEXIBLE_ORACLE_0_BIT_OFFSET);
                    }
                    
                    function _isFlexibleOracle1(bytes32 packedPoolParams) internal pure returns(bool) {
                        return packedPoolParams.decodeBool(_FLEXIBLE_ORACLE_1_BIT_OFFSET);
                    }
                    function _getMaxPerfDev(bytes32 packedPoolParams) internal pure returns (uint256 maxPerfDev) {
                        maxPerfDev = packedPoolParams.decodeUint(_MAX_PERF_DEV_BIT_OFFSET, _MAX_PERF_DEV_BIT_LENGTH);
                    }
                    function _getMaxTargetDev(bytes32 packedPoolParams) internal pure returns (uint256 maxTargetDev) {
                        maxTargetDev = packedPoolParams.decodeUint(_MAX_TARGET_DEV_BIT_OFFSET, _MAX_TARGET_DEV_BIT_LENGTH);
                    }
                    function _getMaxPriceDev(bytes32 packedPoolParams) internal pure returns (uint256 maxPriceDev) {
                        maxPriceDev = packedPoolParams.decodeUint(_MAX_PRICE_DEV_BIT_OFFSET, _MAX_PRICE_DEV_BIT_LENGTH);
                    }
                    function _getPerformanceTimeParams(bytes32 packedPoolParams) internal pure
                    returns(uint256 lastPerfUpdate, uint256 perfUpdateInterval) {
                        
                        lastPerfUpdate = packedPoolParams.decodeUint(_PERF_LAST_UPDATE_BIT_OFFSET, _PERF_TIME_BIT_LENGTH);
                        perfUpdateInterval = packedPoolParams.decodeUint(_PERF_UPDATE_INTERVAL_BIT_OFFSET, _PERF_TIME_BIT_LENGTH);
                    }
                    /// @inheritdoc ISafeguardPool
                    function getOracleParams() external view override returns(OracleParams[] memory) {
                        OracleParams[] memory oracleParams = new OracleParams[](2);
                        bytes32 packedPoolParams = _packedPoolParams;
                        oracleParams[0] = OracleParams({
                            oracle: _oracle0,
                            maxTimeout: _maxOracleTimeout0,
                            isStable: _isStable0,
                            isFlexibleOracle: _isFlexibleOracle0(packedPoolParams),
                            isPegged: _isTokenPegged0(packedPoolParams),
                            priceScalingFactor: _priceScaleFactor0
                        });
                        oracleParams[1] = OracleParams({
                            oracle: _oracle1,
                            maxTimeout: _maxOracleTimeout1,
                            isStable: _isStable1,
                            isFlexibleOracle: _isFlexibleOracle1(packedPoolParams),
                            isPegged: _isTokenPegged1(packedPoolParams),
                            priceScalingFactor: _priceScaleFactor1
                        });
                        return oracleParams;
                    }
                    function _canBePegged(
                        bool isTokenPegged,
                        AggregatorV3Interface oracle,
                        uint256 maxOracleTimeout,
                        uint256 priceScaleFactor
                    ) internal view returns(bool) {
                        uint256 currentPrice = _getPriceFromOracle(oracle, maxOracleTimeout, priceScaleFactor);
                        
                        (uint256 priceMin, uint256 priceMax) = currentPrice < FixedPoint.ONE?
                            (currentPrice, FixedPoint.ONE) : (FixedPoint.ONE, currentPrice);
                        uint256 relativePriceDifference = (priceMax - priceMin);
                        if(!isTokenPegged && relativePriceDifference <= _REPEG_PRICE_BOUND) {
                            return true; // token should gain back peg 
                        } else if (isTokenPegged && relativePriceDifference >= _UNPEG_PRICE_BOUND) {
                            return false; // token should be unpegged
                        }
                        return isTokenPegged;
                    }
                    /// @inheritdoc ISignatureSafeguard
                    function signer() public view override(ISignatureSafeguard, SignatureSafeguard) returns(address){
                        return _signer;
                    }
                    function _getTotalTokens() internal pure override returns (uint256) {
                        return _NUM_TOKENS;
                    }
                    function _getMaxTokens() internal pure override returns (uint256) {
                        return _NUM_TOKENS;
                    }
                    function _scalingFactors() internal view override returns (uint256[] memory) {
                        uint256[] memory scalingFactors = new uint256[](_NUM_TOKENS);
                        scalingFactors[0] = _scaleFactor0;
                        scalingFactors[1] = _scaleFactor1;
                        return scalingFactors;
                    }
                    function _scalingFactor(IERC20 token) internal view override returns (uint256) {
                        if (token == _token0) {
                            return _scaleFactor0;
                        }
                        return _scaleFactor1;
                    }
                    function _scalingFactorsInAndOut(bool isToken0) internal view returns (uint256, uint256) {
                        if (isToken0) {
                            return (_scaleFactor0, _scaleFactor1);
                        }
                        return (_scaleFactor1, _scaleFactor0);
                    }
                    /**
                    * @dev Safeguard pool does not support on-chain swap fees. They should be included in the pricing
                    * of the signed quotes. The following functions are overriden to reduce contract size and disable
                    * on-chain swap fees.
                    */
                    // Safeguard pool does not support on-chain swap fees.
                    function _setSwapFeePercentage(uint256) internal pure override {
                        return;
                    }
                    // Safeguard pool does not support on-chain swap fees.
                    function getSwapFeePercentage() public pure override(BasePool, IBasePool) returns (uint256) {
                        return 0;
                    }
                    // Safeguard pool does not support on-chain swap fees.
                    function _getMinSwapFeePercentage() internal override pure returns (uint256) {
                        return 0;
                    }
                    // Safeguard pool does not support on-chain swap fees.
                    function _getMaxSwapFeePercentage() internal override pure returns (uint256) {
                        return 0;
                    }
                    /*
                    * Management fees
                    */
                   function _onDisableRecoveryMode() internal override {
                        // resets last claim time to the current time in order to prevent claiming fees accrued
                        // when the pool was in recovery mode
                        _previousClaimTime = uint32(block.timestamp);
                    }
                    function _beforeJoinExit() private {
                        _claimManagementFees();
                    }
                    /// @inheritdoc ISafeguardPool
                    function claimManagementFees() external override whenNotPaused {
                        _claimManagementFees();
                    }
                    function _claimManagementFees() internal {
                        uint256 currentTime = block.timestamp;
                        uint256 elapsedTime = currentTime.sub(uint256(_previousClaimTime));
                        
                        if(elapsedTime > 0) {
                            // update last claim time
                            _previousClaimTime = uint32(currentTime);
                            uint256 yearlyRate = uint256(_yearlyRate);
                            uint256 previousTotalSupply = totalSupply();
                            if(yearlyRate > 0) {
                                // returns bpt that needs to be minted
                                uint256 protocolFees = SafeguardMath.calcAccumulatedManagementFees(
                                    elapsedTime,
                                    yearlyRate,
                                    previousTotalSupply
                                );
                                
                                _payProtocolFees(protocolFees);
                                emit ManagementFeesClaimed(protocolFees, previousTotalSupply, yearlyRate, currentTime);
                            }
                        }
                    }
                    /// @inheritdoc ISafeguardPool
                    function setManagementFees(uint256 yearlyFees) external override authenticate whenNotPaused {
                        _setManagementFees(yearlyFees);
                    }
                    function _setManagementFees(uint256 yearlyFees) private {               
                        // claim previous manag
                        _claimManagementFees();
                        
                        _setYearlyRate(yearlyFees);
                    }
                    function _setYearlyRate(uint256 yearlyFees) private {
                        _srequire(yearlyFees <= _MAX_YEARLY_FEES, SwaapV2Errors.FEES_TOO_HIGH);
                        _yearlyFees = uint64(yearlyFees);
                        _yearlyRate = uint56(SafeguardMath.calcYearlyRate(yearlyFees));
                        emit ManagementFeesUpdated(yearlyFees);
                    }
                    /// @inheritdoc ISafeguardPool
                    function getManagementFeesParams() public view override returns(uint256, uint256, uint256) {
                        return (_yearlyFees, _yearlyRate, _previousClaimTime);
                    }
                }// SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity =0.7.6;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/EOASignaturesValidator.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@swaap-labs/v2-interfaces/contracts/safeguard-pool/SafeguardPoolUserData.sol";
                import "@swaap-labs/v2-interfaces/contracts/safeguard-pool/ISignatureSafeguard.sol";
                import "@swaap-labs/v2-errors/contracts/SwaapV2Errors.sol";
                /**
                 * @dev Utility for verifying signed quotes and whitelisted lps. This module should only
                 * be used with pools with a fixed two token order that are similar to that in the vault.
                 */
                abstract contract SignatureSafeguard is EOASignaturesValidator, ISignatureSafeguard {
                    struct ValidatedQuoteData {
                        bytes swapData;
                        bytes32 digest;
                    }
                    using SafeguardPoolUserData for bytes;
                    // solhint-disable max-line-length
                    bytes32 public constant SWAP_STRUCT_TYPEHASH =
                        keccak256(
                            "SwapStruct(uint8 kind,bool isTokenInToken0,address sender,address recipient,bytes swapData,uint256 quoteIndex,uint256 deadline)"
                        );
                    // solhint-enable max-line-length
                    bytes32 public constant ALLOWLIST_STRUCT_TYPEHASH = keccak256("AllowlistStruct(address sender,uint256 deadline)");
                    // NB Do not assign a high value (e.g. max(uint256)) or else it will overflow when adding it to the block.timestamp
                    uint256 private constant _MAX_REMAINING_SIGNATURE_VALIDITY = 5 minutes;
                    mapping(uint256 => uint256) internal _usedQuoteBitMap;
                    /**
                     * @dev The inheriting pool contract must have one and immutable poolId and must
                     * interact with one and immutable vault's address. Otherwise, it is unsafe to rely solely
                     * on the pool's address as a domain seperator assuming that a quote is based on the pool's state.
                     */
                    function _swapSignatureSafeguard(
                        IVault.SwapKind kind,
                        bool isTokenInToken0,
                        address sender,
                        address recipient,
                        bytes calldata userData
                    ) internal returns (bytes memory, bytes32) {
                        (bytes memory swapData, bytes memory signature, uint256 quoteIndex, uint256 deadline)
                           = userData.decodeSignedSwapData();
                        bytes32 digest = _validateSwapSignature(kind, isTokenInToken0, sender, recipient, swapData, signature, quoteIndex, deadline);
                        return (swapData, digest);
                    }
                    /**
                     * @dev The inheriting pool contract must have one and immutable poolId and must
                     * interact with one and immutable vault's address. Otherwise, it is unsafe to rely solely
                     * on the pool's address as a domain seperator assuming that a quote is based on the pool's state.
                     */
                    function _joinExitSwapSignatureSafeguard(
                        address sender,
                        address recipient,
                        bytes memory userData
                    ) internal returns (uint256, uint256[] memory, bool, ValidatedQuoteData memory) {
                        
                        (
                            bool isTokenInToken0, // excess token in or limit token in
                            bytes memory swapData,
                            bytes memory signature,
                            uint256 quoteIndex,
                            uint256 deadline // swap deadline
                        ) = userData.exactJoinExitSwapData();
                        bytes32 digest = _validateSwapSignature(
                            IVault.SwapKind.GIVEN_IN, isTokenInToken0, sender, recipient, swapData, signature, quoteIndex, deadline
                        );
                        (uint256 limitBptAmountOut, uint256[] memory joinExitAmounts) = userData.exactJoinExitAmountsData();
                        return (limitBptAmountOut, joinExitAmounts, isTokenInToken0, ValidatedQuoteData(swapData, digest));
                    }
                    function _validateSwapSignature(
                        IVault.SwapKind kind,
                        bool isTokenInToken0,
                        address sender,
                        address recipient,
                        bytes memory swapData,
                        bytes memory signature,
                        uint256 quoteIndex,
                        uint256 deadline
                    ) internal returns (bytes32) {
                        // For a two token pool,we can only include the tokenIn in the signature. For pools that has more than
                        // two tokens the tokenOut must be specified to ensure the correctness of the trade.
                        bytes32 structHash = keccak256(
                            abi.encode(
                                SWAP_STRUCT_TYPEHASH, kind, isTokenInToken0, sender, recipient,keccak256(swapData), quoteIndex, deadline
                            )
                        );
                        bytes32 digest = _ensureValidBitmapSignature(
                            structHash,
                            signature,
                            quoteIndex,
                            deadline
                        );
                        return digest;
                    }
                    function _ensureValidBitmapSignature(
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 quoteIndex,
                        uint256 deadline
                    ) internal returns (bytes32) {
                        bytes32 digest = _hashTypedDataV4(structHash);
                        _srequire(_isValidSignature(signer(), digest, signature), SwaapV2Errors.BITMAP_SIGNATURE_NOT_VALID);
                        // We could check for the deadline & quote index before validating the signature, but this leads to saner
                        // error processing (as we only care about expired deadlines & quote if the signature is correct) and only
                        // affects the gas cost of the revert scenario, which will only occur infrequently, if ever.
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(deadline >= block.timestamp, Errors.EXPIRED_SIGNATURE);
                        _srequire(!_isQuoteUsed(quoteIndex), SwaapV2Errors.QUOTE_ALREADY_USED);
                        _registerUsedQuote(quoteIndex);
                        return digest;
                    }
                    function _isQuoteUsed(uint256 index) internal view returns (bool) {
                        uint256 usedQuoteWordIndex = index / 256;
                        uint256 usedQuoteBitIndex = index % 256;
                        uint256 usedQuoteWord = _usedQuoteBitMap[usedQuoteWordIndex];
                        uint256 mask = (1 << usedQuoteBitIndex);
                        return usedQuoteWord & mask == mask;
                    }
                    function _registerUsedQuote(uint256 index) private {
                        uint256 usedQuoteWordIndex = index / 256;
                        uint256 usedQuoteBitIndex = index % 256;
                        _usedQuoteBitMap[usedQuoteWordIndex] = _usedQuoteBitMap[usedQuoteWordIndex] | (1 << usedQuoteBitIndex);
                    }
                    function _validateAllowlistSignature(address sender, bytes memory userData) internal returns (bytes memory) {
                        (uint256 deadline, bytes memory signature, bytes memory joinData) = userData.allowlistData();
                        bytes32 structHash = keccak256(abi.encode(ALLOWLIST_STRUCT_TYPEHASH, sender, deadline));
                        bytes32 digest = _ensureValidReplayableSignature(
                            structHash,
                            signature,
                            deadline
                        );
                        emit AllowlistJoinSignatureValidated(digest);
                        return joinData;
                    }
                    function _ensureValidReplayableSignature(
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 deadline
                    ) internal view returns (bytes32) {
                        bytes32 digest = _hashTypedDataV4(structHash);
                        _srequire(_isValidSignature(signer(), digest, signature), SwaapV2Errors.REPLAYABLE_SIGNATURE_NOT_VALID);
                        // We could check for the deadline before validating the signature, but this leads to saner error processing (as
                        // we only care about expired deadlines if the signature is correct) and only affects the gas cost of the revert
                        // scenario, which will only occur infrequently, if ever.
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(deadline >= block.timestamp, Errors.EXPIRED_SIGNATURE);
                        _require(deadline <= block.timestamp + _MAX_REMAINING_SIGNATURE_VALIDITY, Errors.EXPIRED_SIGNATURE);
                        return digest;
                    }
                    /// @inheritdoc ISignatureSafeguard
                    function getQuoteBitmapWord(uint256 wordIndex) external view override returns(uint){
                        return _usedQuoteBitMap[wordIndex];
                    }
                    /// @inheritdoc ISignatureSafeguard
                    function signer() public view override virtual returns (address);
                }
                

                File 3 of 7: Vault
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                // solhint-disable
                /**
                 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
                 * supported.
                 * Uses the default 'BAL' prefix for the error code
                 */
                function _require(bool condition, uint256 errorCode) pure {
                    if (!condition) _revert(errorCode);
                }
                /**
                 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
                 * supported.
                 */
                function _require(
                    bool condition,
                    uint256 errorCode,
                    bytes3 prefix
                ) pure {
                    if (!condition) _revert(errorCode, prefix);
                }
                /**
                 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
                 * Uses the default 'BAL' prefix for the error code
                 */
                function _revert(uint256 errorCode) pure {
                    _revert(errorCode, 0x42414c); // This is the raw byte representation of "BAL"
                }
                /**
                 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
                 */
                function _revert(uint256 errorCode, bytes3 prefix) pure {
                    uint256 prefixUint = uint256(uint24(prefix));
                    // We're going to dynamically create a revert string based on the error code, with the following format:
                    // 'BAL#{errorCode}'
                    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
                    //
                    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
                    // number (8 to 16 bits) than the individual string characters.
                    //
                    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
                    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
                    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
                    assembly {
                        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
                        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
                        // the '0' character.
                        let units := add(mod(errorCode, 10), 0x30)
                        errorCode := div(errorCode, 10)
                        let tenths := add(mod(errorCode, 10), 0x30)
                        errorCode := div(errorCode, 10)
                        let hundreds := add(mod(errorCode, 10), 0x30)
                        // With the individual characters, we can now construct the full string.
                        // We first append the '#' character (0x23) to the prefix. In the case of 'BAL', it results in 0x42414c23 ('BAL#')
                        // Then, we shift this by 24 (to provide space for the 3 bytes of the error code), and add the
                        // characters to it, each shifted by a multiple of 8.
                        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
                        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
                        // array).
                        let formattedPrefix := shl(24, add(0x23, shl(8, prefixUint)))
                        let revertReason := shl(200, add(formattedPrefix, add(add(units, shl(8, tenths)), shl(16, hundreds))))
                        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
                        // message will have the following layout:
                        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
                        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
                        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
                        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
                        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
                        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
                        // The string length is fixed: 7 characters.
                        mstore(0x24, 7)
                        // Finally, the string itself is stored.
                        mstore(0x44, revertReason)
                        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
                        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
                        revert(0, 100)
                    }
                }
                library Errors {
                    // Math
                    uint256 internal constant ADD_OVERFLOW = 0;
                    uint256 internal constant SUB_OVERFLOW = 1;
                    uint256 internal constant SUB_UNDERFLOW = 2;
                    uint256 internal constant MUL_OVERFLOW = 3;
                    uint256 internal constant ZERO_DIVISION = 4;
                    uint256 internal constant DIV_INTERNAL = 5;
                    uint256 internal constant X_OUT_OF_BOUNDS = 6;
                    uint256 internal constant Y_OUT_OF_BOUNDS = 7;
                    uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
                    uint256 internal constant INVALID_EXPONENT = 9;
                    // Input
                    uint256 internal constant OUT_OF_BOUNDS = 100;
                    uint256 internal constant UNSORTED_ARRAY = 101;
                    uint256 internal constant UNSORTED_TOKENS = 102;
                    uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
                    uint256 internal constant ZERO_TOKEN = 104;
                    uint256 internal constant INSUFFICIENT_DATA = 105;
                    // Shared pools
                    uint256 internal constant MIN_TOKENS = 200;
                    uint256 internal constant MAX_TOKENS = 201;
                    uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
                    uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
                    uint256 internal constant MINIMUM_BPT = 204;
                    uint256 internal constant CALLER_NOT_VAULT = 205;
                    uint256 internal constant UNINITIALIZED = 206;
                    uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
                    uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
                    uint256 internal constant EXPIRED_PERMIT = 209;
                    uint256 internal constant NOT_TWO_TOKENS = 210;
                    uint256 internal constant DISABLED = 211;
                    // Pools
                    uint256 internal constant MIN_AMP = 300;
                    uint256 internal constant MAX_AMP = 301;
                    uint256 internal constant MIN_WEIGHT = 302;
                    uint256 internal constant MAX_STABLE_TOKENS = 303;
                    uint256 internal constant MAX_IN_RATIO = 304;
                    uint256 internal constant MAX_OUT_RATIO = 305;
                    uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
                    uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
                    uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
                    uint256 internal constant INVALID_TOKEN = 309;
                    uint256 internal constant UNHANDLED_JOIN_KIND = 310;
                    uint256 internal constant ZERO_INVARIANT = 311;
                    uint256 internal constant ORACLE_INVALID_SECONDS_QUERY = 312;
                    uint256 internal constant ORACLE_NOT_INITIALIZED = 313;
                    uint256 internal constant ORACLE_QUERY_TOO_OLD = 314;
                    uint256 internal constant ORACLE_INVALID_INDEX = 315;
                    uint256 internal constant ORACLE_BAD_SECS = 316;
                    uint256 internal constant AMP_END_TIME_TOO_CLOSE = 317;
                    uint256 internal constant AMP_ONGOING_UPDATE = 318;
                    uint256 internal constant AMP_RATE_TOO_HIGH = 319;
                    uint256 internal constant AMP_NO_ONGOING_UPDATE = 320;
                    uint256 internal constant STABLE_INVARIANT_DIDNT_CONVERGE = 321;
                    uint256 internal constant STABLE_GET_BALANCE_DIDNT_CONVERGE = 322;
                    uint256 internal constant RELAYER_NOT_CONTRACT = 323;
                    uint256 internal constant BASE_POOL_RELAYER_NOT_CALLED = 324;
                    uint256 internal constant REBALANCING_RELAYER_REENTERED = 325;
                    uint256 internal constant GRADUAL_UPDATE_TIME_TRAVEL = 326;
                    uint256 internal constant SWAPS_DISABLED = 327;
                    uint256 internal constant CALLER_IS_NOT_LBP_OWNER = 328;
                    uint256 internal constant PRICE_RATE_OVERFLOW = 329;
                    uint256 internal constant INVALID_JOIN_EXIT_KIND_WHILE_SWAPS_DISABLED = 330;
                    uint256 internal constant WEIGHT_CHANGE_TOO_FAST = 331;
                    uint256 internal constant LOWER_GREATER_THAN_UPPER_TARGET = 332;
                    uint256 internal constant UPPER_TARGET_TOO_HIGH = 333;
                    uint256 internal constant UNHANDLED_BY_LINEAR_POOL = 334;
                    uint256 internal constant OUT_OF_TARGET_RANGE = 335;
                    uint256 internal constant UNHANDLED_EXIT_KIND = 336;
                    uint256 internal constant UNAUTHORIZED_EXIT = 337;
                    uint256 internal constant MAX_MANAGEMENT_SWAP_FEE_PERCENTAGE = 338;
                    uint256 internal constant UNHANDLED_BY_MANAGED_POOL = 339;
                    uint256 internal constant UNHANDLED_BY_PHANTOM_POOL = 340;
                    uint256 internal constant TOKEN_DOES_NOT_HAVE_RATE_PROVIDER = 341;
                    uint256 internal constant INVALID_INITIALIZATION = 342;
                    uint256 internal constant OUT_OF_NEW_TARGET_RANGE = 343;
                    uint256 internal constant FEATURE_DISABLED = 344;
                    uint256 internal constant UNINITIALIZED_POOL_CONTROLLER = 345;
                    uint256 internal constant SET_SWAP_FEE_DURING_FEE_CHANGE = 346;
                    uint256 internal constant SET_SWAP_FEE_PENDING_FEE_CHANGE = 347;
                    uint256 internal constant CHANGE_TOKENS_DURING_WEIGHT_CHANGE = 348;
                    uint256 internal constant CHANGE_TOKENS_PENDING_WEIGHT_CHANGE = 349;
                    uint256 internal constant MAX_WEIGHT = 350;
                    uint256 internal constant UNAUTHORIZED_JOIN = 351;
                    uint256 internal constant MAX_MANAGEMENT_AUM_FEE_PERCENTAGE = 352;
                    uint256 internal constant FRACTIONAL_TARGET = 353;
                    uint256 internal constant ADD_OR_REMOVE_BPT = 354;
                    uint256 internal constant INVALID_CIRCUIT_BREAKER_BOUNDS = 355;
                    uint256 internal constant CIRCUIT_BREAKER_TRIPPED = 356;
                    uint256 internal constant MALICIOUS_QUERY_REVERT = 357;
                    uint256 internal constant JOINS_EXITS_DISABLED = 358;
                    // Lib
                    uint256 internal constant REENTRANCY = 400;
                    uint256 internal constant SENDER_NOT_ALLOWED = 401;
                    uint256 internal constant PAUSED = 402;
                    uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
                    uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
                    uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
                    uint256 internal constant INSUFFICIENT_BALANCE = 406;
                    uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
                    uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
                    uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
                    uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
                    uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
                    uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
                    uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
                    uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
                    uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
                    uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
                    uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
                    uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
                    uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
                    uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
                    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
                    uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
                    uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
                    uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
                    uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
                    uint256 internal constant CALLER_IS_NOT_OWNER = 426;
                    uint256 internal constant NEW_OWNER_IS_ZERO = 427;
                    uint256 internal constant CODE_DEPLOYMENT_FAILED = 428;
                    uint256 internal constant CALL_TO_NON_CONTRACT = 429;
                    uint256 internal constant LOW_LEVEL_CALL_FAILED = 430;
                    uint256 internal constant NOT_PAUSED = 431;
                    uint256 internal constant ADDRESS_ALREADY_ALLOWLISTED = 432;
                    uint256 internal constant ADDRESS_NOT_ALLOWLISTED = 433;
                    uint256 internal constant ERC20_BURN_EXCEEDS_BALANCE = 434;
                    uint256 internal constant INVALID_OPERATION = 435;
                    uint256 internal constant CODEC_OVERFLOW = 436;
                    uint256 internal constant IN_RECOVERY_MODE = 437;
                    uint256 internal constant NOT_IN_RECOVERY_MODE = 438;
                    uint256 internal constant INDUCED_FAILURE = 439;
                    uint256 internal constant EXPIRED_SIGNATURE = 440;
                    uint256 internal constant MALFORMED_SIGNATURE = 441;
                    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_UINT64 = 442;
                    uint256 internal constant UNHANDLED_FEE_TYPE = 443;
                    uint256 internal constant BURN_FROM_ZERO = 444;
                    // Vault
                    uint256 internal constant INVALID_POOL_ID = 500;
                    uint256 internal constant CALLER_NOT_POOL = 501;
                    uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
                    uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
                    uint256 internal constant INVALID_SIGNATURE = 504;
                    uint256 internal constant EXIT_BELOW_MIN = 505;
                    uint256 internal constant JOIN_ABOVE_MAX = 506;
                    uint256 internal constant SWAP_LIMIT = 507;
                    uint256 internal constant SWAP_DEADLINE = 508;
                    uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
                    uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
                    uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
                    uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
                    uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
                    uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
                    uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
                    uint256 internal constant INSUFFICIENT_ETH = 516;
                    uint256 internal constant UNALLOCATED_ETH = 517;
                    uint256 internal constant ETH_TRANSFER = 518;
                    uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
                    uint256 internal constant TOKENS_MISMATCH = 520;
                    uint256 internal constant TOKEN_NOT_REGISTERED = 521;
                    uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
                    uint256 internal constant TOKENS_ALREADY_SET = 523;
                    uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
                    uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
                    uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
                    uint256 internal constant POOL_NO_TOKENS = 527;
                    uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
                    // Fees
                    uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
                    uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
                    uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
                    uint256 internal constant AUM_FEE_PERCENTAGE_TOO_HIGH = 603;
                    // FeeSplitter
                    uint256 internal constant SPLITTER_FEE_PERCENTAGE_TOO_HIGH = 700;
                    // Misc
                    uint256 internal constant UNIMPLEMENTED = 998;
                    uint256 internal constant SHOULD_NOT_HAPPEN = 999;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                interface IAuthentication {
                    /**
                     * @dev Returns the action identifier associated with the external function described by `selector`.
                     */
                    function getActionId(bytes4 selector) external view returns (bytes32);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
                 */
                interface ISignaturesValidator {
                    /**
                     * @dev Returns the EIP712 domain separator.
                     */
                    function getDomainSeparator() external view returns (bytes32);
                    /**
                     * @dev Returns the next nonce used by an address to sign messages.
                     */
                    function getNextNonce(address user) external view returns (uint256);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface for the TemporarilyPausable helper.
                 */
                interface ITemporarilyPausable {
                    /**
                     * @dev Emitted every time the pause state changes by `_setPaused`.
                     */
                    event PausedStateChanged(bool paused);
                    /**
                     * @dev Returns the current paused state.
                     */
                    function getPausedState()
                        external
                        view
                        returns (
                            bool paused,
                            uint256 pauseWindowEndTime,
                            uint256 bufferPeriodEndTime
                        );
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                import "../openzeppelin/IERC20.sol";
                /**
                 * @dev Interface for WETH9.
                 * See https://github.com/gnosis/canonical-weth/blob/0dd1ea3e295eef916d0c6223ec63141137d22d67/contracts/WETH9.sol
                 */
                interface IWETH is IERC20 {
                    function deposit() external payable;
                    function withdraw(uint256 amount) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Interface of the ERC20 standard as defined in the EIP.
                 */
                interface IERC20 {
                    /**
                     * @dev Returns the amount of tokens in existence.
                     */
                    function totalSupply() external view returns (uint256);
                    /**
                     * @dev Returns the amount of tokens owned by `account`.
                     */
                    function balanceOf(address account) external view returns (uint256);
                    /**
                     * @dev Moves `amount` tokens from the caller's account to `recipient`.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * Emits a {Transfer} event.
                     */
                    function transfer(address recipient, uint256 amount) external returns (bool);
                    /**
                     * @dev Returns the remaining number of tokens that `spender` will be
                     * allowed to spend on behalf of `owner` through {transferFrom}. This is
                     * zero by default.
                     *
                     * This value changes when {approve} or {transferFrom} are called.
                     */
                    function allowance(address owner, address spender) external view returns (uint256);
                    /**
                     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * IMPORTANT: Beware that changing an allowance with this method brings the risk
                     * that someone may use both the old and the new allowance by unfortunate
                     * transaction ordering. One possible solution to mitigate this race
                     * condition is to first reduce the spender's allowance to 0 and set the
                     * desired value afterwards:
                     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                     *
                     * Emits an {Approval} event.
                     */
                    function approve(address spender, uint256 amount) external returns (bool);
                    /**
                     * @dev Moves `amount` tokens from `sender` to `recipient` using the
                     * allowance mechanism. `amount` is then deducted from the caller's
                     * allowance.
                     *
                     * Returns a boolean value indicating whether the operation succeeded.
                     *
                     * Emits a {Transfer} event.
                     */
                    function transferFrom(
                        address sender,
                        address recipient,
                        uint256 amount
                    ) external returns (bool);
                    /**
                     * @dev Emitted when `value` tokens are moved from one account (`from`) to
                     * another (`to`).
                     *
                     * Note that `value` may be zero.
                     */
                    event Transfer(address indexed from, address indexed to, uint256 value);
                    /**
                     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                     * a call to {approve}. `value` is the new allowance.
                     */
                    event Approval(address indexed owner, address indexed spender, uint256 value);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
                 * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
                 * types.
                 *
                 * This concept is unrelated to a Pool's Asset Managers.
                 */
                interface IAsset {
                    // solhint-disable-previous-line no-empty-blocks
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                interface IAuthorizer {
                    /**
                     * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
                     */
                    function canPerform(
                        bytes32 actionId,
                        address account,
                        address where
                    ) external view returns (bool);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./IVault.sol";
                import "./IPoolSwapStructs.sol";
                /**
                 * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
                 * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
                 * either IGeneralPool or IMinimalSwapInfoPool
                 */
                interface IBasePool is IPoolSwapStructs {
                    /**
                     * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
                     * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
                     * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
                     * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
                     *
                     * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
                     *
                     * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
                     * designated to receive any benefits (typically pool shares). `balances` contains the total balances
                     * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                     *
                     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                     * balance.
                     *
                     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                     * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                     *
                     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                     * state-changing operations, such as minting pool shares.
                     */
                    function onJoinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
                    /**
                     * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
                     * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
                     * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
                     * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
                     * `protocolSwapFeePercentage`.
                     *
                     * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
                     *
                     * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
                     * to which the Vault will send the proceeds. `balances` contains the total token balances for each token
                     * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                     *
                     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                     * balance.
                     *
                     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                     * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                     *
                     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                     * state-changing operations, such as burning pool shares.
                     */
                    function onExitPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
                    /**
                     * @dev Returns this Pool's ID, used when interacting with the Vault (to e.g. join the Pool or swap with it).
                     */
                    function getPoolId() external view returns (bytes32);
                    /**
                     * @dev Returns the current swap fee percentage as a 18 decimal fixed point number, so e.g. 1e17 corresponds to a
                     * 10% swap fee.
                     */
                    function getSwapFeePercentage() external view returns (uint256);
                    /**
                     * @dev Returns the scaling factors of each of the Pool's tokens. This is an implementation detail that is typically
                     * not relevant for outside parties, but which might be useful for some types of Pools.
                     */
                    function getScalingFactors() external view returns (uint256[] memory);
                    function queryJoin(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256 bptOut, uint256[] memory amountsIn);
                    function queryExit(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        uint256[] memory balances,
                        uint256 lastChangeBlock,
                        uint256 protocolSwapFeePercentage,
                        bytes memory userData
                    ) external returns (uint256 bptIn, uint256[] memory amountsOut);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                // Inspired by Aave Protocol's IFlashLoanReceiver.
                import "../solidity-utils/openzeppelin/IERC20.sol";
                interface IFlashLoanRecipient {
                    /**
                     * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
                     *
                     * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
                     * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
                     * Vault, or else the entire flash loan will revert.
                     *
                     * `userData` is the same value passed in the `IVault.flashLoan` call.
                     */
                    function receiveFlashLoan(
                        IERC20[] memory tokens,
                        uint256[] memory amounts,
                        uint256[] memory feeAmounts,
                        bytes memory userData
                    ) external;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./IBasePool.sol";
                /**
                 * @dev IPools with the General specialization setting should implement this interface.
                 *
                 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
                 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will
                 * grant to the pool in a 'given out' swap.
                 *
                 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
                 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
                 * indeed the Vault.
                 */
                interface IGeneralPool is IBasePool {
                    function onSwap(
                        SwapRequest memory swapRequest,
                        uint256[] memory balances,
                        uint256 indexIn,
                        uint256 indexOut
                    ) external returns (uint256 amount);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "./IBasePool.sol";
                /**
                 * @dev Pool contracts with the MinimalSwapInfo or TwoToken specialization settings should implement this interface.
                 *
                 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
                 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will grant
                 * to the pool in a 'given out' swap.
                 *
                 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
                 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
                 * indeed the Vault.
                 */
                interface IMinimalSwapInfoPool is IBasePool {
                    function onSwap(
                        SwapRequest memory swapRequest,
                        uint256 currentBalanceTokenIn,
                        uint256 currentBalanceTokenOut
                    ) external returns (uint256 amount);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "./IVault.sol";
                interface IPoolSwapStructs {
                    // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
                    // IMinimalSwapInfoPool.
                    //
                    // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
                    // 'given out') which indicates whether or not the amount sent by the pool is known.
                    //
                    // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
                    // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
                    //
                    // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
                    // some Pools.
                    //
                    // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
                    // one Pool.
                    //
                    // The meaning of `lastChangeBlock` depends on the Pool specialization:
                    //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
                    //    balance.
                    //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
                    //
                    // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
                    // where the Pool sends the outgoing tokens.
                    //
                    // `userData` is extra data provided by the caller - typically a signature from a trusted party.
                    struct SwapRequest {
                        IVault.SwapKind kind;
                        IERC20 tokenIn;
                        IERC20 tokenOut;
                        uint256 amount;
                        // Misc data
                        bytes32 poolId;
                        uint256 lastChangeBlock;
                        address from;
                        address to;
                        bytes userData;
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity >=0.7.0 <0.9.0;
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "./IVault.sol";
                import "./IAuthorizer.sol";
                interface IProtocolFeesCollector {
                    event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
                    event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
                    function withdrawCollectedFees(
                        IERC20[] calldata tokens,
                        uint256[] calldata amounts,
                        address recipient
                    ) external;
                    function setSwapFeePercentage(uint256 newSwapFeePercentage) external;
                    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external;
                    function getSwapFeePercentage() external view returns (uint256);
                    function getFlashLoanFeePercentage() external view returns (uint256);
                    function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts);
                    function getAuthorizer() external view returns (IAuthorizer);
                    function vault() external view returns (IVault);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma experimental ABIEncoderV2;
                import "../solidity-utils/openzeppelin/IERC20.sol";
                import "../solidity-utils/helpers/IAuthentication.sol";
                import "../solidity-utils/helpers/ISignaturesValidator.sol";
                import "../solidity-utils/helpers/ITemporarilyPausable.sol";
                import "../solidity-utils/misc/IWETH.sol";
                import "./IAsset.sol";
                import "./IAuthorizer.sol";
                import "./IFlashLoanRecipient.sol";
                import "./IProtocolFeesCollector.sol";
                pragma solidity >=0.7.0 <0.9.0;
                /**
                 * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
                 * don't override one of these declarations.
                 */
                interface IVault is ISignaturesValidator, ITemporarilyPausable, IAuthentication {
                    // Generalities about the Vault:
                    //
                    // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
                    // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
                    // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
                    // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
                    // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
                    //
                    // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
                    // while execution control is transferred to a token contract during a swap) will result in a revert. View
                    // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
                    // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
                    //
                    // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
                    // Authorizer
                    //
                    // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
                    // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
                    // can perform a given action.
                    /**
                     * @dev Returns the Vault's Authorizer.
                     */
                    function getAuthorizer() external view returns (IAuthorizer);
                    /**
                     * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
                     *
                     * Emits an `AuthorizerChanged` event.
                     */
                    function setAuthorizer(IAuthorizer newAuthorizer) external;
                    /**
                     * @dev Emitted when a new authorizer is set by `setAuthorizer`.
                     */
                    event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
                    // Relayers
                    //
                    // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
                    // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
                    // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
                    // this power, two things must occur:
                    //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
                    //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
                    //    functions.
                    //  - Each user must approve the relayer to act on their behalf.
                    // This double protection means users cannot be tricked into approving malicious relayers (because they will not
                    // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
                    // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
                    /**
                     * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
                     */
                    function hasApprovedRelayer(address user, address relayer) external view returns (bool);
                    /**
                     * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
                     *
                     * Emits a `RelayerApprovalChanged` event.
                     */
                    function setRelayerApproval(
                        address sender,
                        address relayer,
                        bool approved
                    ) external;
                    /**
                     * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
                     */
                    event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
                    // Internal Balance
                    //
                    // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
                    // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
                    // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
                    // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
                    //
                    // Internal Balance management features batching, which means a single contract call can be used to perform multiple
                    // operations of different kinds, with different senders and recipients, at once.
                    /**
                     * @dev Returns `user`'s Internal Balance for a set of tokens.
                     */
                    function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
                    /**
                     * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
                     * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
                     * it lets integrators reuse a user's Vault allowance.
                     *
                     * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
                     */
                    function manageUserBalance(UserBalanceOp[] memory ops) external payable;
                    /**
                     * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
                     without manual WETH wrapping or unwrapping.
                     */
                    struct UserBalanceOp {
                        UserBalanceOpKind kind;
                        IAsset asset;
                        uint256 amount;
                        address sender;
                        address payable recipient;
                    }
                    // There are four possible operations in `manageUserBalance`:
                    //
                    // - DEPOSIT_INTERNAL
                    // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
                    // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
                    //
                    // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
                    // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
                    // relevant for relayers).
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - WITHDRAW_INTERNAL
                    // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
                    //
                    // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
                    // it to the recipient as ETH.
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - TRANSFER_INTERNAL
                    // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
                    //
                    // Reverts if the ETH sentinel value is passed.
                    //
                    // Emits an `InternalBalanceChanged` event.
                    //
                    //
                    // - TRANSFER_EXTERNAL
                    // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
                    // relayers, as it lets them reuse a user's Vault allowance.
                    //
                    // Reverts if the ETH sentinel value is passed.
                    //
                    // Emits an `ExternalBalanceTransfer` event.
                    enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
                    /**
                     * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
                     * interacting with Pools using Internal Balance.
                     *
                     * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
                     * address.
                     */
                    event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
                    /**
                     * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
                     */
                    event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
                    // Pools
                    //
                    // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
                    // functionality:
                    //
                    //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
                    // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
                    // which increase with the number of registered tokens.
                    //
                    //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
                    // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
                    // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
                    // independent of the number of registered tokens.
                    //
                    //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
                    // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
                    enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
                    /**
                     * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
                     * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
                     * changed.
                     *
                     * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
                     * depending on the chosen specialization setting. This contract is known as the Pool's contract.
                     *
                     * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
                     * multiple Pools may share the same contract.
                     *
                     * Emits a `PoolRegistered` event.
                     */
                    function registerPool(PoolSpecialization specialization) external returns (bytes32);
                    /**
                     * @dev Emitted when a Pool is registered by calling `registerPool`.
                     */
                    event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
                    /**
                     * @dev Returns a Pool's contract address and specialization setting.
                     */
                    function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
                    /**
                     * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                     *
                     * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
                     * exit by receiving registered tokens, and can only swap registered tokens.
                     *
                     * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
                     * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
                     * ascending order.
                     *
                     * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
                     * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
                     * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
                     * expected to be highly secured smart contracts with sound design principles, and the decision to register an
                     * Asset Manager should not be made lightly.
                     *
                     * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
                     * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
                     * different Asset Manager.
                     *
                     * Emits a `TokensRegistered` event.
                     */
                    function registerTokens(
                        bytes32 poolId,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) external;
                    /**
                     * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
                     */
                    event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
                    /**
                     * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                     *
                     * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
                     * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
                     * must be deregistered in the same `deregisterTokens` call.
                     *
                     * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
                     *
                     * Emits a `TokensDeregistered` event.
                     */
                    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
                    /**
                     * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
                     */
                    event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
                    /**
                     * @dev Returns detailed information for a Pool's registered token.
                     *
                     * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
                     * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
                     * equals the sum of `cash` and `managed`.
                     *
                     * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
                     * `managed` or `total` balance to be greater than 2^112 - 1.
                     *
                     * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
                     * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
                     * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
                     * change for this purpose, and will update `lastChangeBlock`.
                     *
                     * `assetManager` is the Pool's token Asset Manager.
                     */
                    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                        external
                        view
                        returns (
                            uint256 cash,
                            uint256 managed,
                            uint256 lastChangeBlock,
                            address assetManager
                        );
                    /**
                     * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
                     * the tokens' `balances` changed.
                     *
                     * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
                     * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
                     *
                     * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
                     * order as passed to `registerTokens`.
                     *
                     * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
                     * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
                     * instead.
                     */
                    function getPoolTokens(bytes32 poolId)
                        external
                        view
                        returns (
                            IERC20[] memory tokens,
                            uint256[] memory balances,
                            uint256 lastChangeBlock
                        );
                    /**
                     * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
                     * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
                     * Pool shares.
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
                     * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
                     * these maximums.
                     *
                     * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
                     * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
                     * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
                     * back to the caller (not the sender, which is important for relayers).
                     *
                     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                     * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
                     * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
                     * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
                     *
                     * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
                     * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
                     * withdrawn from Internal Balance: attempting to do so will trigger a revert.
                     *
                     * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
                     * their own custom logic. This typically requires additional information from the user (such as the expected number
                     * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
                     * directly to the Pool's contract, as is `recipient`.
                     *
                     * Emits a `PoolBalanceChanged` event.
                     */
                    function joinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        JoinPoolRequest memory request
                    ) external payable;
                    struct JoinPoolRequest {
                        IAsset[] assets;
                        uint256[] maxAmountsIn;
                        bytes userData;
                        bool fromInternalBalance;
                    }
                    /**
                     * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
                     * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
                     * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
                     * `getPoolTokenInfo`).
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
                     * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
                     * it just enforces these minimums.
                     *
                     * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
                     * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
                     * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
                     *
                     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                     * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
                     * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
                     * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
                     *
                     * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
                     * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
                     * do so will trigger a revert.
                     *
                     * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
                     * `tokens` array. This array must match the Pool's registered tokens.
                     *
                     * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
                     * their own custom logic. This typically requires additional information from the user (such as the expected number
                     * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
                     * passed directly to the Pool's contract.
                     *
                     * Emits a `PoolBalanceChanged` event.
                     */
                    function exitPool(
                        bytes32 poolId,
                        address sender,
                        address payable recipient,
                        ExitPoolRequest memory request
                    ) external;
                    struct ExitPoolRequest {
                        IAsset[] assets;
                        uint256[] minAmountsOut;
                        bytes userData;
                        bool toInternalBalance;
                    }
                    /**
                     * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
                     */
                    event PoolBalanceChanged(
                        bytes32 indexed poolId,
                        address indexed liquidityProvider,
                        IERC20[] tokens,
                        int256[] deltas,
                        uint256[] protocolFeeAmounts
                    );
                    enum PoolBalanceChangeKind { JOIN, EXIT }
                    // Swaps
                    //
                    // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
                    // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
                    // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
                    //
                    // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
                    // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
                    // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
                    // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
                    // individual swaps.
                    //
                    // There are two swap kinds:
                    //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
                    // `onSwap` hook) the amount of tokens out (to send to the recipient).
                    //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
                    // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
                    //
                    // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
                    // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
                    // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
                    // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
                    // the final intended token.
                    //
                    // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
                    // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
                    // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
                    // much less gas than they would otherwise.
                    //
                    // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
                    // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
                    // updating the Pool's internal accounting).
                    //
                    // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
                    // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
                    // minimum amount of tokens to receive (by passing a negative value) is specified.
                    //
                    // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
                    // this point in time (e.g. if the transaction failed to be included in a block promptly).
                    //
                    // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
                    // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
                    // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
                    // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
                    //
                    // Finally, Internal Balance can be used when either sending or receiving tokens.
                    enum SwapKind { GIVEN_IN, GIVEN_OUT }
                    /**
                     * @dev Performs a swap with a single Pool.
                     *
                     * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
                     * taken from the Pool, which must be greater than or equal to `limit`.
                     *
                     * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
                     * sent to the Pool, which must be less than or equal to `limit`.
                     *
                     * Internal Balance usage and the recipient are determined by the `funds` struct.
                     *
                     * Emits a `Swap` event.
                     */
                    function swap(
                        SingleSwap memory singleSwap,
                        FundManagement memory funds,
                        uint256 limit,
                        uint256 deadline
                    ) external payable returns (uint256);
                    /**
                     * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
                     * the `kind` value.
                     *
                     * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
                     * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
                     *
                     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                     * used to extend swap behavior.
                     */
                    struct SingleSwap {
                        bytes32 poolId;
                        SwapKind kind;
                        IAsset assetIn;
                        IAsset assetOut;
                        uint256 amount;
                        bytes userData;
                    }
                    /**
                     * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
                     * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
                     *
                     * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
                     * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
                     * the same index in the `assets` array.
                     *
                     * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
                     * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
                     * `amountOut` depending on the swap kind.
                     *
                     * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
                     * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
                     * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
                     *
                     * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
                     * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
                     * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
                     * or unwrapped from WETH by the Vault.
                     *
                     * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
                     * the minimum or maximum amount of each token the vault is allowed to transfer.
                     *
                     * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
                     * equivalent `swap` call.
                     *
                     * Emits `Swap` events.
                     */
                    function batchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds,
                        int256[] memory limits,
                        uint256 deadline
                    ) external payable returns (int256[] memory);
                    /**
                     * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
                     * `assets` array passed to that function, and ETH assets are converted to WETH.
                     *
                     * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
                     * from the previous swap, depending on the swap kind.
                     *
                     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                     * used to extend swap behavior.
                     */
                    struct BatchSwapStep {
                        bytes32 poolId;
                        uint256 assetInIndex;
                        uint256 assetOutIndex;
                        uint256 amount;
                        bytes userData;
                    }
                    /**
                     * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
                     */
                    event Swap(
                        bytes32 indexed poolId,
                        IERC20 indexed tokenIn,
                        IERC20 indexed tokenOut,
                        uint256 amountIn,
                        uint256 amountOut
                    );
                    /**
                     * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
                     * `recipient` account.
                     *
                     * If the caller is not `sender`, it must be an authorized relayer for them.
                     *
                     * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
                     * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
                     * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
                     * `joinPool`.
                     *
                     * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
                     * transferred. This matches the behavior of `exitPool`.
                     *
                     * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
                     * revert.
                     */
                    struct FundManagement {
                        address sender;
                        bool fromInternalBalance;
                        address payable recipient;
                        bool toInternalBalance;
                    }
                    /**
                     * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
                     * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
                     *
                     * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
                     * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
                     * receives are the same that an equivalent `batchSwap` call would receive.
                     *
                     * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
                     * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
                     * approve them for the Vault, or even know a user's address.
                     *
                     * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
                     * eth_call instead of eth_sendTransaction.
                     */
                    function queryBatchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds
                    ) external returns (int256[] memory assetDeltas);
                    // Flash Loans
                    /**
                     * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
                     * and then reverting unless the tokens plus a proportional protocol fee have been returned.
                     *
                     * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
                     * for each token contract. `tokens` must be sorted in ascending order.
                     *
                     * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
                     * `receiveFlashLoan` call.
                     *
                     * Emits `FlashLoan` events.
                     */
                    function flashLoan(
                        IFlashLoanRecipient recipient,
                        IERC20[] memory tokens,
                        uint256[] memory amounts,
                        bytes memory userData
                    ) external;
                    /**
                     * @dev Emitted for each individual flash loan performed by `flashLoan`.
                     */
                    event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
                    // Asset Management
                    //
                    // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
                    // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
                    // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
                    // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
                    // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
                    // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
                    //
                    // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
                    // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
                    //
                    // This concept is unrelated to the IAsset interface.
                    /**
                     * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
                     *
                     * Pool Balance management features batching, which means a single contract call can be used to perform multiple
                     * operations of different kinds, with different Pools and tokens, at once.
                     *
                     * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
                     */
                    function managePoolBalance(PoolBalanceOp[] memory ops) external;
                    struct PoolBalanceOp {
                        PoolBalanceOpKind kind;
                        bytes32 poolId;
                        IERC20 token;
                        uint256 amount;
                    }
                    /**
                     * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
                     *
                     * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
                     *
                     * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
                     * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
                     */
                    enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
                    /**
                     * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
                     */
                    event PoolBalanceManaged(
                        bytes32 indexed poolId,
                        address indexed assetManager,
                        IERC20 indexed token,
                        int256 cashDelta,
                        int256 managedDelta
                    );
                    // Protocol Fees
                    //
                    // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
                    // permissioned accounts.
                    //
                    // There are two kinds of protocol fees:
                    //
                    //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
                    //
                    //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
                    // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
                    // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
                    // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
                    // exiting a Pool in debt without first paying their share.
                    /**
                     * @dev Returns the current protocol fee module.
                     */
                    function getProtocolFeesCollector() external view returns (IProtocolFeesCollector);
                    /**
                     * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
                     * error in some part of the system.
                     *
                     * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
                     *
                     * While the contract is paused, the following features are disabled:
                     * - depositing and transferring internal balance
                     * - transferring external balance (using the Vault's allowance)
                     * - swaps
                     * - joining Pools
                     * - Asset Manager interactions
                     *
                     * Internal Balance can still be withdrawn, and Pools exited.
                     */
                    function setPaused(bool paused) external;
                    /**
                     * @dev Returns the Vault's WETH instance.
                     */
                    function WETH() external view returns (IWETH);
                    // solhint-disable-previous-line func-name-mixedcase
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IAuthentication.sol";
                /**
                 * @dev Building block for performing access control on external functions.
                 *
                 * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
                 * to external functions to only make them callable by authorized accounts.
                 *
                 * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
                 */
                abstract contract Authentication is IAuthentication {
                    bytes32 private immutable _actionIdDisambiguator;
                    /**
                     * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
                     * multi contract systems.
                     *
                     * There are two main uses for it:
                     *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
                     *    unique. The contract's own address is a good option.
                     *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
                     *    shared by the entire family (and no other contract) should be used instead.
                     */
                    constructor(bytes32 actionIdDisambiguator) {
                        _actionIdDisambiguator = actionIdDisambiguator;
                    }
                    /**
                     * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
                     */
                    modifier authenticate() {
                        _authenticateCaller();
                        _;
                    }
                    /**
                     * @dev Reverts unless the caller is allowed to call the entry point function.
                     */
                    function _authenticateCaller() internal view {
                        bytes32 actionId = getActionId(msg.sig);
                        _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
                    }
                    function getActionId(bytes4 selector) public view override returns (bytes32) {
                        // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
                        // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
                        // multiple contracts.
                        return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
                    }
                    function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ISignaturesValidator.sol";
                import "../openzeppelin/EIP712.sol";
                /**
                 * @dev Utility for signing Solidity function calls.
                 */
                abstract contract EOASignaturesValidator is ISignaturesValidator, EIP712 {
                    // Replay attack prevention for each account.
                    mapping(address => uint256) internal _nextNonce;
                    function getDomainSeparator() public view override returns (bytes32) {
                        return _domainSeparatorV4();
                    }
                    function getNextNonce(address account) public view override returns (uint256) {
                        return _nextNonce[account];
                    }
                    function _ensureValidSignature(
                        address account,
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 errorCode
                    ) internal {
                        return _ensureValidSignature(account, structHash, signature, type(uint256).max, errorCode);
                    }
                    function _ensureValidSignature(
                        address account,
                        bytes32 structHash,
                        bytes memory signature,
                        uint256 deadline,
                        uint256 errorCode
                    ) internal {
                        bytes32 digest = _hashTypedDataV4(structHash);
                        _require(_isValidSignature(account, digest, signature), errorCode);
                        // We could check for the deadline before validating the signature, but this leads to saner error processing (as
                        // we only care about expired deadlines if the signature is correct) and only affects the gas cost of the revert
                        // scenario, which will only occur infrequently, if ever.
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(deadline >= block.timestamp, Errors.EXPIRED_SIGNATURE);
                        // We only advance the nonce after validating the signature. This is irrelevant for this module, but it can be
                        // important in derived contracts that override _isValidSignature (e.g. SignaturesValidator), as we want for
                        // the observable state to still have the current nonce as the next valid one.
                        _nextNonce[account] += 1;
                    }
                    function _isValidSignature(
                        address account,
                        bytes32 digest,
                        bytes memory signature
                    ) internal view virtual returns (bool) {
                        _require(signature.length == 65, Errors.MALFORMED_SIGNATURE);
                        bytes32 r;
                        bytes32 s;
                        uint8 v;
                        // ecrecover takes the r, s and v signature parameters, and the only way to get them is to use assembly.
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            r := mload(add(signature, 0x20))
                            s := mload(add(signature, 0x40))
                            v := byte(0, mload(add(signature, 0x60)))
                        }
                        address recoveredAddress = ecrecover(digest, v, r, s);
                        // ecrecover returns the zero address on recover failure, so we need to handle that explicitly.
                        return (recoveredAddress != address(0) && recoveredAddress == account);
                    }
                    function _toArraySignature(
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) internal pure returns (bytes memory) {
                        bytes memory signature = new bytes(65);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            mstore(add(signature, 32), r)
                            mstore(add(signature, 64), s)
                            mstore8(add(signature, 96), v)
                        }
                        return signature;
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "./EOASignaturesValidator.sol";
                /**
                 * @dev Utility for signing Solidity function calls.
                 *
                 * This contract relies on the fact that Solidity contracts can be called with extra calldata, and enables
                 * meta-transaction schemes by appending an EIP712 signature of the original calldata at the end.
                 *
                 * Derived contracts must implement the `_entrypointTypeHash` function to map function selectors to EIP712 structs.
                 */
                abstract contract ExtraCalldataEOASignaturesValidator is EOASignaturesValidator {
                    // The appended data consists of a deadline, plus the [v,r,s] signature. For simplicity, we use a full 256 bit slot
                    // for each of these values, even if 'v' is typically an 8 bit value.
                    uint256 internal constant _EXTRA_CALLDATA_LENGTH = 4 * 32;
                    /**
                     * @dev Reverts with `errorCode` unless a valid signature for `user` was appended to the calldata.
                     */
                    function _validateExtraCalldataSignature(address user, uint256 errorCode) internal {
                        bytes32 typeHash = _entrypointTypeHash();
                        // Prevent accidental signature validation for functions that don't have an associated type hash.
                        _require(typeHash != bytes32(0), errorCode);
                        uint256 deadline = _deadline();
                        // All type hashes have this format: (bytes calldata, address sender, uint256 nonce, uint256 deadline).
                        bytes32 structHash = keccak256(
                            abi.encode(typeHash, keccak256(_calldata()), msg.sender, getNextNonce(user), deadline)
                        );
                        _ensureValidSignature(user, structHash, _signature(), deadline, errorCode);
                    }
                    /**
                     * @dev Returns the EIP712 type hash for the current entry point function, which can be identified by its function
                     * selector (available as `msg.sig`).
                     *
                     * The type hash must conform to the following format:
                     *  <name>(bytes calldata, address sender, uint256 nonce, uint256 deadline)
                     *
                     * If 0x00, all signatures will be considered invalid.
                     */
                    function _entrypointTypeHash() internal view virtual returns (bytes32);
                    /**
                     * @dev Extracts the signature deadline from extra calldata.
                     *
                     * This function returns bogus data if no signature is included.
                     */
                    function _deadline() internal pure returns (uint256) {
                        // The deadline is the first extra argument at the end of the original calldata.
                        return uint256(_decodeExtraCalldataWord(0));
                    }
                    /**
                     * @dev Extracts the signature parameters from extra calldata.
                     *
                     * This function returns bogus data if no signature is included. This is not a security risk, as that data would not
                     * be considered a valid signature in the first place.
                     */
                    function _signature() internal pure returns (bytes memory) {
                        // v, r and s are appended after the signature deadline, in that order.
                        uint8 v = uint8(uint256(_decodeExtraCalldataWord(0x20)));
                        bytes32 r = _decodeExtraCalldataWord(0x40);
                        bytes32 s = _decodeExtraCalldataWord(0x60);
                        return _toArraySignature(v, r, s);
                    }
                    /**
                     * @dev Returns the original calldata, without the extra bytes containing the signature.
                     *
                     * This function returns bogus data if no signature is included.
                     */
                    function _calldata() internal pure returns (bytes memory result) {
                        result = msg.data; // A calldata to memory assignment results in memory allocation and copy of contents.
                        if (result.length > _EXTRA_CALLDATA_LENGTH) {
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                // We simply overwrite the array length with the reduced one.
                                mstore(result, sub(calldatasize(), _EXTRA_CALLDATA_LENGTH))
                            }
                        }
                    }
                    /**
                     * @dev Returns a 256 bit word from 'extra' calldata, at some offset from the expected end of the original calldata.
                     *
                     * This function returns bogus data if no signature is included.
                     */
                    function _decodeExtraCalldataWord(uint256 offset) private pure returns (bytes32 result) {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            result := calldataload(add(sub(calldatasize(), _EXTRA_CALLDATA_LENGTH), offset))
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                library InputHelpers {
                    function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
                        _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
                    }
                    function ensureInputLengthMatch(
                        uint256 a,
                        uint256 b,
                        uint256 c
                    ) internal pure {
                        _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
                    }
                    function ensureArrayIsSorted(IERC20[] memory array) internal pure {
                        address[] memory addressArray;
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            addressArray := array
                        }
                        ensureArrayIsSorted(addressArray);
                    }
                    function ensureArrayIsSorted(address[] memory array) internal pure {
                        if (array.length < 2) {
                            return;
                        }
                        address previous = array[0];
                        for (uint256 i = 1; i < array.length; ++i) {
                            address current = array[i];
                            _require(previous < current, Errors.UNSORTED_ARRAY);
                            previous = current;
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ITemporarilyPausable.sol";
                /**
                 * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
                 * used as an emergency switch in case a security vulnerability or threat is identified.
                 *
                 * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
                 * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
                 * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
                 * analysis later determines there was a false alarm.
                 *
                 * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
                 * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
                 * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
                 *
                 * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
                 * irreversible.
                 */
                abstract contract TemporarilyPausable is ITemporarilyPausable {
                    // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
                    // solhint-disable not-rely-on-time
                    uint256 private immutable _pauseWindowEndTime;
                    uint256 private immutable _bufferPeriodEndTime;
                    bool private _paused;
                    constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
                        _require(pauseWindowDuration <= PausableConstants.MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
                        _require(
                            bufferPeriodDuration <= PausableConstants.MAX_BUFFER_PERIOD_DURATION,
                            Errors.MAX_BUFFER_PERIOD_DURATION
                        );
                        uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
                        _pauseWindowEndTime = pauseWindowEndTime;
                        _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
                    }
                    /**
                     * @dev Reverts if the contract is paused.
                     */
                    modifier whenNotPaused() {
                        _ensureNotPaused();
                        _;
                    }
                    /**
                     * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
                     * Period.
                     */
                    function getPausedState()
                        external
                        view
                        override
                        returns (
                            bool paused,
                            uint256 pauseWindowEndTime,
                            uint256 bufferPeriodEndTime
                        )
                    {
                        paused = !_isNotPaused();
                        pauseWindowEndTime = _getPauseWindowEndTime();
                        bufferPeriodEndTime = _getBufferPeriodEndTime();
                    }
                    /**
                     * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
                     * unpaused until the end of the Buffer Period.
                     *
                     * Once the Buffer Period expires, this function reverts unconditionally.
                     */
                    function _setPaused(bool paused) internal {
                        if (paused) {
                            _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
                        } else {
                            _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
                        }
                        _paused = paused;
                        emit PausedStateChanged(paused);
                    }
                    /**
                     * @dev Reverts if the contract is paused.
                     */
                    function _ensureNotPaused() internal view {
                        _require(_isNotPaused(), Errors.PAUSED);
                    }
                    /**
                     * @dev Reverts if the contract is not paused.
                     */
                    function _ensurePaused() internal view {
                        _require(!_isNotPaused(), Errors.NOT_PAUSED);
                    }
                    /**
                     * @dev Returns true if the contract is unpaused.
                     *
                     * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
                     * longer accessed.
                     */
                    function _isNotPaused() internal view returns (bool) {
                        // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
                        return block.timestamp > _getBufferPeriodEndTime() || !_paused;
                    }
                    // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
                    function _getPauseWindowEndTime() private view returns (uint256) {
                        return _pauseWindowEndTime;
                    }
                    function _getBufferPeriodEndTime() private view returns (uint256) {
                        return _bufferPeriodEndTime;
                    }
                }
                /**
                 * @dev Keep the maximum durations in a single place.
                 */
                library PausableConstants {
                    uint256 public constant MAX_PAUSE_WINDOW_DURATION = 270 days;
                    uint256 public constant MAX_BUFFER_PERIOD_DURATION = 90 days;
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "./LogExpMath.sol";
                /* solhint-disable private-vars-leading-underscore */
                library FixedPoint {
                    // solhint-disable no-inline-assembly
                    uint256 internal constant ONE = 1e18; // 18 decimal places
                    uint256 internal constant TWO = 2 * ONE;
                    uint256 internal constant FOUR = 4 * ONE;
                    uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
                    // Minimum base for the power function when the exponent is 'free' (larger than ONE).
                    uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        // Fixed Point addition is the same as regular checked addition
                        uint256 c = a + b;
                        _require(c >= a, Errors.ADD_OVERFLOW);
                        return c;
                    }
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        // Fixed Point addition is the same as regular checked addition
                        _require(b <= a, Errors.SUB_OVERFLOW);
                        uint256 c = a - b;
                        return c;
                    }
                    function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 product = a * b;
                        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                        return product / ONE;
                    }
                    function mulUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        uint256 product = a * b;
                        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, if x == 0 then the result is zero
                        //
                        // Equivalent to:
                        // result = product == 0 ? 0 : ((product - 1) / FixedPoint.ONE) + 1;
                        assembly {
                            result := mul(iszero(iszero(product)), add(div(sub(product, 1), ONE), 1))
                        }
                    }
                    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        uint256 aInflated = a * ONE;
                        _require(a == 0 || aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        return aInflated / b;
                    }
                    function divUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        uint256 aInflated = a * ONE;
                        _require(a == 0 || aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, if x == 0 then the result is zero
                        //
                        // Equivalent to:
                        // result = a == 0 ? 0 : (a * FixedPoint.ONE - 1) / b + 1;
                        assembly {
                            result := mul(iszero(iszero(aInflated)), add(div(sub(aInflated, 1), b), 1))
                        }
                    }
                    /**
                     * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
                     * the true value (that is, the error function expected - actual is always positive).
                     */
                    function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
                        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
                        // and 80/20 Weighted Pools
                        if (y == ONE) {
                            return x;
                        } else if (y == TWO) {
                            return mulDown(x, x);
                        } else if (y == FOUR) {
                            uint256 square = mulDown(x, x);
                            return mulDown(square, square);
                        } else {
                            uint256 raw = LogExpMath.pow(x, y);
                            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                            if (raw < maxError) {
                                return 0;
                            } else {
                                return sub(raw, maxError);
                            }
                        }
                    }
                    /**
                     * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
                     * the true value (that is, the error function expected - actual is always negative).
                     */
                    function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
                        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
                        // and 80/20 Weighted Pools
                        if (y == ONE) {
                            return x;
                        } else if (y == TWO) {
                            return mulUp(x, x);
                        } else if (y == FOUR) {
                            uint256 square = mulUp(x, x);
                            return mulUp(square, square);
                        } else {
                            uint256 raw = LogExpMath.pow(x, y);
                            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                            return add(raw, maxError);
                        }
                    }
                    /**
                     * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
                     *
                     * Useful when computing the complement for values with some level of relative error, as it strips this error and
                     * prevents intermediate negative values.
                     */
                    function complement(uint256 x) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = (x < ONE) ? (ONE - x) : 0;
                        assembly {
                            result := mul(lt(x, ONE), sub(ONE, x))
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                // Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
                // documentation files (the “Software”), to deal in the Software without restriction, including without limitation the
                // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
                // permit persons to whom the Software is furnished to do so, subject to the following conditions:
                // The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
                // Software.
                // THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
                // WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
                // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
                // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /* solhint-disable */
                /**
                 * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
                 *
                 * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
                 * exponentiation and logarithm (where the base is Euler's number).
                 *
                 * @author Fernando Martinelli - @fernandomartinelli
                 * @author Sergio Yuhjtman - @sergioyuhjtman
                 * @author Daniel Fernandez - @dmf7z
                 */
                library LogExpMath {
                    // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
                    // two numbers, and multiply by ONE when dividing them.
                    // All arguments and return values are 18 decimal fixed point numbers.
                    int256 constant ONE_18 = 1e18;
                    // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
                    // case of ln36, 36 decimals.
                    int256 constant ONE_20 = 1e20;
                    int256 constant ONE_36 = 1e36;
                    // The domain of natural exponentiation is bound by the word size and number of decimals used.
                    //
                    // Because internally the result will be stored using 20 decimals, the largest possible result is
                    // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
                    // The smallest possible result is 10^(-18), which makes largest negative argument
                    // ln(10^(-18)) = -41.446531673892822312.
                    // We use 130.0 and -41.0 to have some safety margin.
                    int256 constant MAX_NATURAL_EXPONENT = 130e18;
                    int256 constant MIN_NATURAL_EXPONENT = -41e18;
                    // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
                    // 256 bit integer.
                    int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
                    int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
                    uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
                    // 18 decimal constants
                    int256 constant x0 = 128000000000000000000; // 2ˆ7
                    int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
                    int256 constant x1 = 64000000000000000000; // 2ˆ6
                    int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
                    // 20 decimal constants
                    int256 constant x2 = 3200000000000000000000; // 2ˆ5
                    int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
                    int256 constant x3 = 1600000000000000000000; // 2ˆ4
                    int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
                    int256 constant x4 = 800000000000000000000; // 2ˆ3
                    int256 constant a4 = 298095798704172827474000; // eˆ(x4)
                    int256 constant x5 = 400000000000000000000; // 2ˆ2
                    int256 constant a5 = 5459815003314423907810; // eˆ(x5)
                    int256 constant x6 = 200000000000000000000; // 2ˆ1
                    int256 constant a6 = 738905609893065022723; // eˆ(x6)
                    int256 constant x7 = 100000000000000000000; // 2ˆ0
                    int256 constant a7 = 271828182845904523536; // eˆ(x7)
                    int256 constant x8 = 50000000000000000000; // 2ˆ-1
                    int256 constant a8 = 164872127070012814685; // eˆ(x8)
                    int256 constant x9 = 25000000000000000000; // 2ˆ-2
                    int256 constant a9 = 128402541668774148407; // eˆ(x9)
                    int256 constant x10 = 12500000000000000000; // 2ˆ-3
                    int256 constant a10 = 113314845306682631683; // eˆ(x10)
                    int256 constant x11 = 6250000000000000000; // 2ˆ-4
                    int256 constant a11 = 106449445891785942956; // eˆ(x11)
                    /**
                     * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
                     *
                     * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
                     */
                    function pow(uint256 x, uint256 y) internal pure returns (uint256) {
                        if (y == 0) {
                            // We solve the 0^0 indetermination by making it equal one.
                            return uint256(ONE_18);
                        }
                        if (x == 0) {
                            return 0;
                        }
                        // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
                        // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
                        // x^y = exp(y * ln(x)).
                        // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
                        _require(x >> 255 == 0, Errors.X_OUT_OF_BOUNDS);
                        int256 x_int256 = int256(x);
                        // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
                        // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
                        // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
                        _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
                        int256 y_int256 = int256(y);
                        int256 logx_times_y;
                        if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
                            int256 ln_36_x = _ln_36(x_int256);
                            // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
                            // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
                            // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
                            // (downscaled) last 18 decimals.
                            logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
                        } else {
                            logx_times_y = _ln(x_int256) * y_int256;
                        }
                        logx_times_y /= ONE_18;
                        // Finally, we compute exp(y * ln(x)) to arrive at x^y
                        _require(
                            MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
                            Errors.PRODUCT_OUT_OF_BOUNDS
                        );
                        return uint256(exp(logx_times_y));
                    }
                    /**
                     * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
                     *
                     * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
                     */
                    function exp(int256 x) internal pure returns (int256) {
                        _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
                        if (x < 0) {
                            // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
                            // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
                            // Fixed point division requires multiplying by ONE_18.
                            return ((ONE_18 * ONE_18) / exp(-x));
                        }
                        // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
                        // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
                        // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
                        // decomposition.
                        // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
                        // decomposition, which will be lower than the smallest x_n.
                        // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
                        // We mutate x by subtracting x_n, making it the remainder of the decomposition.
                        // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
                        // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
                        // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
                        // decomposition.
                        // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
                        // it and compute the accumulated product.
                        int256 firstAN;
                        if (x >= x0) {
                            x -= x0;
                            firstAN = a0;
                        } else if (x >= x1) {
                            x -= x1;
                            firstAN = a1;
                        } else {
                            firstAN = 1; // One with no decimal places
                        }
                        // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
                        // smaller terms.
                        x *= 100;
                        // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
                        // one. Recall that fixed point multiplication requires dividing by ONE_20.
                        int256 product = ONE_20;
                        if (x >= x2) {
                            x -= x2;
                            product = (product * a2) / ONE_20;
                        }
                        if (x >= x3) {
                            x -= x3;
                            product = (product * a3) / ONE_20;
                        }
                        if (x >= x4) {
                            x -= x4;
                            product = (product * a4) / ONE_20;
                        }
                        if (x >= x5) {
                            x -= x5;
                            product = (product * a5) / ONE_20;
                        }
                        if (x >= x6) {
                            x -= x6;
                            product = (product * a6) / ONE_20;
                        }
                        if (x >= x7) {
                            x -= x7;
                            product = (product * a7) / ONE_20;
                        }
                        if (x >= x8) {
                            x -= x8;
                            product = (product * a8) / ONE_20;
                        }
                        if (x >= x9) {
                            x -= x9;
                            product = (product * a9) / ONE_20;
                        }
                        // x10 and x11 are unnecessary here since we have high enough precision already.
                        // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
                        // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
                        int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
                        int256 term; // Each term in the sum, where the nth term is (x^n / n!).
                        // The first term is simply x.
                        term = x;
                        seriesSum += term;
                        // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
                        // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
                        term = ((term * x) / ONE_20) / 2;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 3;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 4;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 5;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 6;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 7;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 8;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 9;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 10;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 11;
                        seriesSum += term;
                        term = ((term * x) / ONE_20) / 12;
                        seriesSum += term;
                        // 12 Taylor terms are sufficient for 18 decimal precision.
                        // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
                        // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
                        // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
                        // and then drop two digits to return an 18 decimal value.
                        return (((product * seriesSum) / ONE_20) * firstAN) / 100;
                    }
                    /**
                     * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument.
                     */
                    function log(int256 arg, int256 base) internal pure returns (int256) {
                        // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
                        // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
                        // upscaling.
                        int256 logBase;
                        if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
                            logBase = _ln_36(base);
                        } else {
                            logBase = _ln(base) * ONE_18;
                        }
                        int256 logArg;
                        if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
                            logArg = _ln_36(arg);
                        } else {
                            logArg = _ln(arg) * ONE_18;
                        }
                        // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
                        return (logArg * ONE_18) / logBase;
                    }
                    /**
                     * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                     */
                    function ln(int256 a) internal pure returns (int256) {
                        // The real natural logarithm is not defined for negative numbers or zero.
                        _require(a > 0, Errors.OUT_OF_BOUNDS);
                        if (LN_36_LOWER_BOUND < a && a < LN_36_UPPER_BOUND) {
                            return _ln_36(a) / ONE_18;
                        } else {
                            return _ln(a);
                        }
                    }
                    /**
                     * @dev Internal natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                     */
                    function _ln(int256 a) private pure returns (int256) {
                        if (a < ONE_18) {
                            // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
                            // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
                            // Fixed point division requires multiplying by ONE_18.
                            return (-_ln((ONE_18 * ONE_18) / a));
                        }
                        // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
                        // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
                        // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
                        // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
                        // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
                        // decomposition, which will be lower than the smallest a_n.
                        // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
                        // We mutate a by subtracting a_n, making it the remainder of the decomposition.
                        // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
                        // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
                        // ONE_18 to convert them to fixed point.
                        // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
                        // by it and compute the accumulated sum.
                        int256 sum = 0;
                        if (a >= a0 * ONE_18) {
                            a /= a0; // Integer, not fixed point division
                            sum += x0;
                        }
                        if (a >= a1 * ONE_18) {
                            a /= a1; // Integer, not fixed point division
                            sum += x1;
                        }
                        // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
                        sum *= 100;
                        a *= 100;
                        // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
                        if (a >= a2) {
                            a = (a * ONE_20) / a2;
                            sum += x2;
                        }
                        if (a >= a3) {
                            a = (a * ONE_20) / a3;
                            sum += x3;
                        }
                        if (a >= a4) {
                            a = (a * ONE_20) / a4;
                            sum += x4;
                        }
                        if (a >= a5) {
                            a = (a * ONE_20) / a5;
                            sum += x5;
                        }
                        if (a >= a6) {
                            a = (a * ONE_20) / a6;
                            sum += x6;
                        }
                        if (a >= a7) {
                            a = (a * ONE_20) / a7;
                            sum += x7;
                        }
                        if (a >= a8) {
                            a = (a * ONE_20) / a8;
                            sum += x8;
                        }
                        if (a >= a9) {
                            a = (a * ONE_20) / a9;
                            sum += x9;
                        }
                        if (a >= a10) {
                            a = (a * ONE_20) / a10;
                            sum += x10;
                        }
                        if (a >= a11) {
                            a = (a * ONE_20) / a11;
                            sum += x11;
                        }
                        // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
                        // that converges rapidly for values of `a` close to one - the same one used in ln_36.
                        // Let z = (a - 1) / (a + 1).
                        // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                        // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
                        // division by ONE_20.
                        int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
                        int256 z_squared = (z * z) / ONE_20;
                        // num is the numerator of the series: the z^(2 * n + 1) term
                        int256 num = z;
                        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                        int256 seriesSum = num;
                        // In each step, the numerator is multiplied by z^2
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 3;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 5;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 7;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 9;
                        num = (num * z_squared) / ONE_20;
                        seriesSum += num / 11;
                        // 6 Taylor terms are sufficient for 36 decimal precision.
                        // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
                        seriesSum *= 2;
                        // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
                        // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
                        // value.
                        return (sum + seriesSum) / 100;
                    }
                    /**
                     * @dev Intrnal high precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
                     * for x close to one.
                     *
                     * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
                     */
                    function _ln_36(int256 x) private pure returns (int256) {
                        // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
                        // worthwhile.
                        // First, we transform x to a 36 digit fixed point value.
                        x *= ONE_18;
                        // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
                        // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                        // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
                        // division by ONE_36.
                        int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
                        int256 z_squared = (z * z) / ONE_36;
                        // num is the numerator of the series: the z^(2 * n + 1) term
                        int256 num = z;
                        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                        int256 seriesSum = num;
                        // In each step, the numerator is multiplied by z^2
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 3;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 5;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 7;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 9;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 11;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 13;
                        num = (num * z_squared) / ONE_36;
                        seriesSum += num / 15;
                        // 8 Taylor terms are sufficient for 36 decimal precision.
                        // All that remains is multiplying by 2 (non fixed point).
                        return seriesSum * 2;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
                 * Adapted from OpenZeppelin's SafeMath library.
                 */
                library Math {
                    // solhint-disable no-inline-assembly
                    /**
                     * @dev Returns the absolute value of a signed integer.
                     */
                    function abs(int256 a) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = a > 0 ? uint256(a) : uint256(-a)
                        assembly {
                            let s := sar(255, a)
                            result := sub(xor(a, s), s)
                        }
                    }
                    /**
                     * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
                     */
                    function add(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a + b;
                        _require(c >= a, Errors.ADD_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the addition of two signed integers, reverting on overflow.
                     */
                    function add(int256 a, int256 b) internal pure returns (int256) {
                        int256 c = a + b;
                        _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
                     */
                    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b <= a, Errors.SUB_OVERFLOW);
                        uint256 c = a - b;
                        return c;
                    }
                    /**
                     * @dev Returns the subtraction of two signed integers, reverting on overflow.
                     */
                    function sub(int256 a, int256 b) internal pure returns (int256) {
                        int256 c = a - b;
                        _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
                        return c;
                    }
                    /**
                     * @dev Returns the largest of two numbers of 256 bits.
                     */
                    function max(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        // Equivalent to:
                        // result = (a < b) ? b : a;
                        assembly {
                            result := sub(a, mul(sub(a, b), lt(a, b)))
                        }
                    }
                    /**
                     * @dev Returns the smallest of two numbers of 256 bits.
                     */
                    function min(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        // Equivalent to `result = (a < b) ? a : b`
                        assembly {
                            result := sub(a, mul(sub(a, b), gt(a, b)))
                        }
                    }
                    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                        uint256 c = a * b;
                        _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
                        return c;
                    }
                    function div(
                        uint256 a,
                        uint256 b,
                        bool roundUp
                    ) internal pure returns (uint256) {
                        return roundUp ? divUp(a, b) : divDown(a, b);
                    }
                    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        return a / b;
                    }
                    function divUp(uint256 a, uint256 b) internal pure returns (uint256 result) {
                        _require(b != 0, Errors.ZERO_DIVISION);
                        // Equivalent to:
                        // result = a == 0 ? 0 : 1 + (a - 1) / b;
                        assembly {
                            result := mul(iszero(iszero(a)), add(1, div(sub(a, 1), b)))
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the Address library from OpenZeppelin Contracts, altered by removing the `isContract` checks on
                // `functionCall` and `functionDelegateCall` in order to save gas, as the recipients are known to be contracts.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Collection of functions related to the address type
                 */
                library Address {
                    /**
                     * @dev Returns true if `account` is a contract.
                     *
                     * [IMPORTANT]
                     * ====
                     * It is unsafe to assume that an address for which this function returns
                     * false is an externally-owned account (EOA) and not a contract.
                     *
                     * Among others, `isContract` will return false for the following
                     * types of addresses:
                     *
                     *  - an externally-owned account
                     *  - a contract in construction
                     *  - an address where a contract will be created
                     *  - an address where a contract lived, but was destroyed
                     * ====
                     */
                    function isContract(address account) internal view returns (bool) {
                        // This method relies on extcodesize, which returns 0 for contracts in
                        // construction, since the code is only stored at the end of the
                        // constructor execution.
                        uint256 size;
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            size := extcodesize(account)
                        }
                        return size > 0;
                    }
                    // solhint-disable max-line-length
                    /**
                     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                     * `recipient`, forwarding all available gas and reverting on errors.
                     *
                     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                     * of certain opcodes, possibly making contracts go over the 2300 gas limit
                     * imposed by `transfer`, making them unable to receive funds via
                     * `transfer`. {sendValue} removes this limitation.
                     *
                     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                     *
                     * IMPORTANT: because control is transferred to `recipient`, care must be
                     * taken to not create reentrancy vulnerabilities. Consider using
                     * {ReentrancyGuard} or the
                     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                     */
                    function sendValue(address payable recipient, uint256 amount) internal {
                        _require(address(this).balance >= amount, Errors.ADDRESS_INSUFFICIENT_BALANCE);
                        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                        (bool success, ) = recipient.call{ value: amount }("");
                        _require(success, Errors.ADDRESS_CANNOT_SEND_VALUE);
                    }
                    /**
                     * @dev Performs a Solidity function call using a low level `call`. A
                     * plain `call` is an unsafe replacement for a function call: use this
                     * function instead.
                     *
                     * If `target` reverts with a revert reason, it is bubbled up by this
                     * function (like regular Solidity function calls).
                     *
                     * Returns the raw returned data. To convert to the expected return value,
                     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                     *
                     * Requirements:
                     *
                     * - calling `target` with `data` must not revert.
                     *
                     * _Available since v3.1._
                     */
                    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, bytes memory returndata) = target.call(data);
                        return verifyCallResult(success, returndata);
                    }
                    // solhint-enable max-line-length
                    /**
                     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                     * but passing some native ETH as msg.value to the call.
                     *
                     * _Available since v3.4._
                     */
                    function functionCallWithValue(
                        address target,
                        bytes memory data,
                        uint256 value
                    ) internal returns (bytes memory) {
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, bytes memory returndata) = target.call{ value: value }(data);
                        return verifyCallResult(success, returndata);
                    }
                    /**
                     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                     * but performing a delegate call.
                     *
                     * _Available since v3.4._
                     */
                    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, bytes memory returndata) = target.delegatecall(data);
                        return verifyCallResult(success, returndata);
                    }
                    /**
                     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling up the
                     * revert reason or using the one provided.
                     *
                     * _Available since v4.3._
                     */
                    function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) {
                        if (success) {
                            return returndata;
                        } else {
                            // Look for revert reason and bubble it up if present
                            if (returndata.length > 0) {
                                // The easiest way to bubble the revert reason is using memory via assembly
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    let returndata_size := mload(returndata)
                                    revert(add(32, returndata), returndata_size)
                                }
                            } else {
                                _revert(Errors.LOW_LEVEL_CALL_FAILED);
                            }
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                /**
                 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
                 *
                 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
                 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
                 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
                 *
                 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
                 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
                 * ({_hashTypedDataV4}).
                 *
                 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
                 * the chain id to protect against replay attacks on an eventual fork of the chain.
                 *
                 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
                 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
                 *
                 * _Available since v3.4._
                 */
                abstract contract EIP712 {
                    /* solhint-disable var-name-mixedcase */
                    bytes32 private immutable _HASHED_NAME;
                    bytes32 private immutable _HASHED_VERSION;
                    bytes32 private immutable _TYPE_HASH;
                    /* solhint-enable var-name-mixedcase */
                    /**
                     * @dev Initializes the domain separator and parameter caches.
                     *
                     * The meaning of `name` and `version` is specified in
                     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
                     *
                     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
                     * - `version`: the current major version of the signing domain.
                     *
                     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
                     * contract upgrade].
                     */
                    constructor(string memory name, string memory version) {
                        _HASHED_NAME = keccak256(bytes(name));
                        _HASHED_VERSION = keccak256(bytes(version));
                        _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
                    }
                    /**
                     * @dev Returns the domain separator for the current chain.
                     */
                    function _domainSeparatorV4() internal view virtual returns (bytes32) {
                        return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
                    }
                    /**
                     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
                     * function returns the hash of the fully encoded EIP712 message for this domain.
                     *
                     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
                     *
                     * ```solidity
                     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
                     *     keccak256("Mail(address to,string contents)"),
                     *     mailTo,
                     *     keccak256(bytes(mailContents))
                     * )));
                     * address signer = ECDSA.recover(digest, signature);
                     * ```
                     */
                    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                        return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
                    }
                    // solc-ignore-next-line func-mutability
                    function _getChainId() private view returns (uint256 chainId) {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            chainId := chainid()
                        }
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the EnumerableMap library from OpenZeppelin Contracts, altered to include the following:
                //  * a map from IERC20 to bytes32
                //  * entries are stored in mappings instead of arrays, reducing implicit storage reads for out-of-bounds checks
                //  * unchecked_at and unchecked_valueAt, which allow for more gas efficient data reads in some scenarios
                //  * indexOf, unchecked_indexOf and unchecked_setAt, which allow for more gas efficient data writes in some scenarios
                //
                // Additionally, the base private functions that work on bytes32 were removed and replaced with a native implementation
                // for IERC20 keys, to reduce bytecode size and runtime costs.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                /**
                 * @dev Library for managing an enumerable variant of Solidity's
                 * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
                 * type.
                 *
                 * Maps have the following properties:
                 *
                 * - Entries are added, removed, and checked for existence in constant time
                 * (O(1)).
                 * - Entries are enumerated in O(n). No guarantees are made on the ordering.
                 *
                 * ```
                 * contract Example {
                 *     // Add the library methods
                 *     using EnumerableMap for EnumerableMap.UintToAddressMap;
                 *
                 *     // Declare a set state variable
                 *     EnumerableMap.UintToAddressMap private myMap;
                 * }
                 * ```
                 */
                library EnumerableMap {
                    // The original OpenZeppelin implementation uses a generic Map type with bytes32 keys: this was replaced with
                    // IERC20ToBytes32Map and IERC20ToUint256Map, resulting in more dense bytecode (as long as each contract only uses
                    // one of these - there'll otherwise be duplicated code).
                    // IERC20ToBytes32Map
                    // solhint-disable func-name-mixedcase
                    struct IERC20ToBytes32MapEntry {
                        IERC20 _key;
                        bytes32 _value;
                    }
                    struct IERC20ToBytes32Map {
                        // Number of entries in the map
                        uint256 _length;
                        // Storage of map keys and values
                        mapping(uint256 => IERC20ToBytes32MapEntry) _entries;
                        // Position of the entry defined by a key in the `entries` array, plus 1
                        // because index 0 means a key is not in the map.
                        mapping(IERC20 => uint256) _indexes;
                    }
                    /**
                     * @dev Adds a key-value pair to a map, or updates the value for an existing
                     * key. O(1).
                     *
                     * Returns true if the key was added to the map, that is if it was not
                     * already present.
                     */
                    function set(
                        IERC20ToBytes32Map storage map,
                        IERC20 key,
                        bytes32 value
                    ) internal returns (bool) {
                        // We read and store the key's index to prevent multiple reads from the same storage slot
                        uint256 keyIndex = map._indexes[key];
                        // Equivalent to !contains(map, key)
                        if (keyIndex == 0) {
                            uint256 previousLength = map._length;
                            map._entries[previousLength] = IERC20ToBytes32MapEntry({ _key: key, _value: value });
                            map._length = previousLength + 1;
                            // The entry is stored at previousLength, but we add 1 to all indexes
                            // and use 0 as a sentinel value
                            map._indexes[key] = previousLength + 1;
                            return true;
                        } else {
                            map._entries[keyIndex - 1]._value = value;
                            return false;
                        }
                    }
                    /**
                     * @dev Updates the value for an entry, given its key's index. The key index can be retrieved via
                     * {unchecked_indexOf}, and it should be noted that key indices may change when calling {set} or {remove}. O(1).
                     *
                     * This function performs one less storage read than {set}, but it should only be used when `index` is known to be
                     * within bounds.
                     */
                    function unchecked_setAt(
                        IERC20ToBytes32Map storage map,
                        uint256 index,
                        bytes32 value
                    ) internal {
                        map._entries[index]._value = value;
                    }
                    /**
                     * @dev Removes a key-value pair from a map. O(1).
                     *
                     * Returns true if the key was removed from the map, that is if it was present.
                     */
                    function remove(IERC20ToBytes32Map storage map, IERC20 key) internal returns (bool) {
                        // We read and store the key's index to prevent multiple reads from the same storage slot
                        uint256 keyIndex = map._indexes[key];
                        // Equivalent to contains(map, key)
                        if (keyIndex != 0) {
                            // To delete a key-value pair from the _entries pseudo-array in O(1), we swap the entry to delete with the
                            // one at the highest index, and then remove this last entry (sometimes called as 'swap and pop').
                            // This modifies the order of the pseudo-array, as noted in {at}.
                            uint256 toDeleteIndex = keyIndex - 1;
                            uint256 lastIndex = map._length - 1;
                            // The swap is only necessary if we're not removing the last element
                            if (toDeleteIndex != lastIndex) {
                                IERC20ToBytes32MapEntry storage lastEntry = map._entries[lastIndex];
                                // Move the last entry to the index where the entry to delete is
                                map._entries[toDeleteIndex] = lastEntry;
                                // Update the index for the moved entry
                                map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based
                            }
                            // Delete the slot where the moved entry was stored
                            delete map._entries[lastIndex];
                            map._length = lastIndex;
                            // Delete the index for the deleted slot
                            delete map._indexes[key];
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Returns true if the key is in the map. O(1).
                     */
                    function contains(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (bool) {
                        return map._indexes[key] != 0;
                    }
                    /**
                     * @dev Returns the number of key-value pairs in the map. O(1).
                     */
                    function length(IERC20ToBytes32Map storage map) internal view returns (uint256) {
                        return map._length;
                    }
                    /**
                     * @dev Returns the key-value pair stored at position `index` in the map. O(1).
                     *
                     * Note that there are no guarantees on the ordering of entries inside the
                     * array, and it may change when more entries are added or removed.
                     *
                     * Requirements:
                     *
                     * - `index` must be strictly less than {length}.
                     */
                    function at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
                        _require(map._length > index, Errors.OUT_OF_BOUNDS);
                        return unchecked_at(map, index);
                    }
                    /**
                     * @dev Same as {at}, except this doesn't revert if `index` it outside of the map (i.e. if it is equal or larger
                     * than {length}). O(1).
                     *
                     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                     * within bounds.
                     */
                    function unchecked_at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
                        IERC20ToBytes32MapEntry storage entry = map._entries[index];
                        return (entry._key, entry._value);
                    }
                    /**
                     * @dev Same as {unchecked_At}, except it only returns the value and not the key (performing one less storage
                     * read). O(1).
                     */
                    function unchecked_valueAt(IERC20ToBytes32Map storage map, uint256 index) internal view returns (bytes32) {
                        return map._entries[index]._value;
                    }
                    /**
                     * @dev Returns the value associated with `key`. O(1).
                     *
                     * Requirements:
                     *
                     * - `key` must be in the map. Reverts with `errorCode` otherwise.
                     */
                    function get(
                        IERC20ToBytes32Map storage map,
                        IERC20 key,
                        uint256 errorCode
                    ) internal view returns (bytes32) {
                        uint256 index = map._indexes[key];
                        _require(index > 0, errorCode);
                        return unchecked_valueAt(map, index - 1);
                    }
                    /**
                     * @dev Returns the index for `key`.
                     *
                     * Requirements:
                     *
                     * - `key` must be in the map.
                     */
                    function indexOf(
                        IERC20ToBytes32Map storage map,
                        IERC20 key,
                        uint256 errorCode
                    ) internal view returns (uint256) {
                        uint256 uncheckedIndex = unchecked_indexOf(map, key);
                        _require(uncheckedIndex != 0, errorCode);
                        return uncheckedIndex - 1;
                    }
                    /**
                     * @dev Returns the index for `key` **plus one**. Does not revert if the key is not in the map, and returns 0
                     * instead.
                     */
                    function unchecked_indexOf(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (uint256) {
                        return map._indexes[key];
                    }
                    // IERC20ToUint256Map
                    struct IERC20ToUint256MapEntry {
                        IERC20 _key;
                        uint256 _value;
                    }
                    struct IERC20ToUint256Map {
                        // Number of entries in the map
                        uint256 _length;
                        // Storage of map keys and values
                        mapping(uint256 => IERC20ToUint256MapEntry) _entries;
                        // Position of the entry defined by a key in the `entries` array, plus 1
                        // because index 0 means a key is not in the map.
                        mapping(IERC20 => uint256) _indexes;
                    }
                    /**
                     * @dev Adds a key-value pair to a map, or updates the value for an existing
                     * key. O(1).
                     *
                     * Returns true if the key was added to the map, that is if it was not
                     * already present.
                     */
                    function set(
                        IERC20ToUint256Map storage map,
                        IERC20 key,
                        uint256 value
                    ) internal returns (bool) {
                        // We read and store the key's index to prevent multiple reads from the same storage slot
                        uint256 keyIndex = map._indexes[key];
                        // Equivalent to !contains(map, key)
                        if (keyIndex == 0) {
                            uint256 previousLength = map._length;
                            map._entries[previousLength] = IERC20ToUint256MapEntry({ _key: key, _value: value });
                            map._length = previousLength + 1;
                            // The entry is stored at previousLength, but we add 1 to all indexes
                            // and use 0 as a sentinel value
                            map._indexes[key] = previousLength + 1;
                            return true;
                        } else {
                            map._entries[keyIndex - 1]._value = value;
                            return false;
                        }
                    }
                    /**
                     * @dev Updates the value for an entry, given its key's index. The key index can be retrieved via
                     * {unchecked_indexOf}, and it should be noted that key indices may change when calling {set} or {remove}. O(1).
                     *
                     * This function performs one less storage read than {set}, but it should only be used when `index` is known to be
                     * within bounds.
                     */
                    function unchecked_setAt(
                        IERC20ToUint256Map storage map,
                        uint256 index,
                        uint256 value
                    ) internal {
                        map._entries[index]._value = value;
                    }
                    /**
                     * @dev Removes a key-value pair from a map. O(1).
                     *
                     * Returns true if the key was removed from the map, that is if it was present.
                     */
                    function remove(IERC20ToUint256Map storage map, IERC20 key) internal returns (bool) {
                        // We read and store the key's index to prevent multiple reads from the same storage slot
                        uint256 keyIndex = map._indexes[key];
                        // Equivalent to contains(map, key)
                        if (keyIndex != 0) {
                            // To delete a key-value pair from the _entries pseudo-array in O(1), we swap the entry to delete with the
                            // one at the highest index, and then remove this last entry (sometimes called as 'swap and pop').
                            // This modifies the order of the pseudo-array, as noted in {at}.
                            uint256 toDeleteIndex = keyIndex - 1;
                            uint256 lastIndex = map._length - 1;
                            // The swap is only necessary if we're not removing the last element
                            if (toDeleteIndex != lastIndex) {
                                IERC20ToUint256MapEntry storage lastEntry = map._entries[lastIndex];
                                // Move the last entry to the index where the entry to delete is
                                map._entries[toDeleteIndex] = lastEntry;
                                // Update the index for the moved entry
                                map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based
                            }
                            // Delete the slot where the moved entry was stored
                            delete map._entries[lastIndex];
                            map._length = lastIndex;
                            // Delete the index for the deleted slot
                            delete map._indexes[key];
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Returns true if the key is in the map. O(1).
                     */
                    function contains(IERC20ToUint256Map storage map, IERC20 key) internal view returns (bool) {
                        return map._indexes[key] != 0;
                    }
                    /**
                     * @dev Returns the number of key-value pairs in the map. O(1).
                     */
                    function length(IERC20ToUint256Map storage map) internal view returns (uint256) {
                        return map._length;
                    }
                    /**
                     * @dev Returns the key-value pair stored at position `index` in the map. O(1).
                     *
                     * Note that there are no guarantees on the ordering of entries inside the
                     * array, and it may change when more entries are added or removed.
                     *
                     * Requirements:
                     *
                     * - `index` must be strictly less than {length}.
                     */
                    function at(IERC20ToUint256Map storage map, uint256 index) internal view returns (IERC20, uint256) {
                        _require(map._length > index, Errors.OUT_OF_BOUNDS);
                        return unchecked_at(map, index);
                    }
                    /**
                     * @dev Same as {at}, except this doesn't revert if `index` it outside of the map (i.e. if it is equal or larger
                     * than {length}). O(1).
                     *
                     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                     * within bounds.
                     */
                    function unchecked_at(IERC20ToUint256Map storage map, uint256 index) internal view returns (IERC20, uint256) {
                        IERC20ToUint256MapEntry storage entry = map._entries[index];
                        return (entry._key, entry._value);
                    }
                    /**
                     * @dev Same as {unchecked_At}, except it only returns the value and not the key (performing one less storage
                     * read). O(1).
                     */
                    function unchecked_valueAt(IERC20ToUint256Map storage map, uint256 index) internal view returns (uint256) {
                        return map._entries[index]._value;
                    }
                    /**
                     * @dev Returns the value associated with `key`. O(1).
                     *
                     * Requirements:
                     *
                     * - `key` must be in the map. Reverts with `errorCode` otherwise.
                     */
                    function get(
                        IERC20ToUint256Map storage map,
                        IERC20 key,
                        uint256 errorCode
                    ) internal view returns (uint256) {
                        uint256 index = map._indexes[key];
                        _require(index > 0, errorCode);
                        return unchecked_valueAt(map, index - 1);
                    }
                    /**
                     * @dev Returns the index for `key`.
                     *
                     * Requirements:
                     *
                     * - `key` must be in the map.
                     */
                    function indexOf(
                        IERC20ToUint256Map storage map,
                        IERC20 key,
                        uint256 errorCode
                    ) internal view returns (uint256) {
                        uint256 uncheckedIndex = unchecked_indexOf(map, key);
                        _require(uncheckedIndex != 0, errorCode);
                        return uncheckedIndex - 1;
                    }
                    /**
                     * @dev Returns the index for `key` **plus one**. Does not revert if the key is not in the map, and returns 0
                     * instead.
                     */
                    function unchecked_indexOf(IERC20ToUint256Map storage map, IERC20 key) internal view returns (uint256) {
                        return map._indexes[key];
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the EnumerableSet library from OpenZeppelin Contracts, altered to remove the base private functions that
                // work on bytes32, replacing them with a native implementation for address and bytes32 values, to reduce bytecode
                // size and runtime costs.
                // The `unchecked_at` function was also added, which allows for more gas efficient data reads in some scenarios.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Library for managing
                 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
                 * types.
                 *
                 * Sets have the following properties:
                 *
                 * - Elements are added, removed, and checked for existence in constant time
                 * (O(1)).
                 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
                 *
                 * ```
                 * contract Example {
                 *     // Add the library methods
                 *     using EnumerableSet for EnumerableSet.AddressSet;
                 *
                 *     // Declare a set state variable
                 *     EnumerableSet.AddressSet private mySet;
                 * }
                 * ```
                 *
                 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
                 * and `uint256` (`UintSet`) are supported.
                 */
                library EnumerableSet {
                    // The original OpenZeppelin implementation uses a generic Set type with bytes32 values: this was replaced with
                    // AddressSet, which uses address keys natively, resulting in more dense bytecode.
                    struct AddressSet {
                        // Storage of set values
                        address[] _values;
                        // Position of the value in the `values` array, plus 1 because index 0
                        // means a value is not in the set.
                        mapping(address => uint256) _indexes;
                    }
                    /**
                     * @dev Add a value to a set. O(1).
                     *
                     * Returns true if the value was added to the set, if it was not already present.
                     */
                    function add(AddressSet storage set, address value) internal returns (bool) {
                        if (!contains(set, value)) {
                            set._values.push(value);
                            // The value is stored at length-1, but we add 1 to all indexes
                            // and use 0 as a sentinel value
                            set._indexes[value] = set._values.length;
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Removes a value from a set. O(1).
                     *
                     * Returns true if the value was removed from the set, that is if it was
                     * present.
                     */
                    function remove(AddressSet storage set, address value) internal returns (bool) {
                        // We read and store the value's index to prevent multiple reads from the same storage slot
                        uint256 valueIndex = set._indexes[value];
                        if (valueIndex != 0) {
                            // Equivalent to contains(set, value)
                            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                            // the array, and then remove the last element (sometimes called as 'swap and pop').
                            // This modifies the order of the array, as noted in {at}.
                            uint256 toDeleteIndex = valueIndex - 1;
                            uint256 lastIndex = set._values.length - 1;
                            // The swap is only necessary if we're not removing the last element
                            if (toDeleteIndex != lastIndex) {
                                address lastValue = set._values[lastIndex];
                                // Move the last value to the index where the value to delete is
                                set._values[toDeleteIndex] = lastValue;
                                // Update the index for the moved value
                                set._indexes[lastValue] = toDeleteIndex + 1; // All indexes are 1-based
                            }
                            // Delete the slot where the moved value was stored
                            set._values.pop();
                            // Delete the index for the deleted slot
                            delete set._indexes[value];
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Returns true if the value is in the set. O(1).
                     */
                    function contains(AddressSet storage set, address value) internal view returns (bool) {
                        return set._indexes[value] != 0;
                    }
                    /**
                     * @dev Returns the number of values on the set. O(1).
                     */
                    function length(AddressSet storage set) internal view returns (uint256) {
                        return set._values.length;
                    }
                    /**
                     * @dev Returns the value stored at position `index` in the set. O(1).
                     *
                     * Note that there are no guarantees on the ordering of values inside the
                     * array, and it may change when more values are added or removed.
                     *
                     * Requirements:
                     *
                     * - `index` must be strictly less than {length}.
                     */
                    function at(AddressSet storage set, uint256 index) internal view returns (address) {
                        _require(set._values.length > index, Errors.OUT_OF_BOUNDS);
                        return unchecked_at(set, index);
                    }
                    /**
                     * @dev Same as {at}, except this doesn't revert if `index` it outside of the set (i.e. if it is equal or larger
                     * than {length}). O(1).
                     *
                     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                     * within bounds.
                     */
                    // solhint-disable-next-line func-name-mixedcase
                    function unchecked_at(AddressSet storage set, uint256 index) internal view returns (address) {
                        return set._values[index];
                    }
                    function rawIndexOf(AddressSet storage set, address value) internal view returns (uint256) {
                        return set._indexes[value] - 1;
                    }
                    struct Bytes32Set {
                        // Storage of set values
                        bytes32[] _values;
                        // Position of the value in the `values` array, plus 1 because index 0
                        // means a value is not in the set.
                        mapping(bytes32 => uint256) _indexes;
                    }
                    /**
                     * @dev Add a value to a set. O(1).
                     *
                     * Returns true if the value was added to the set, that is if it was not
                     * already present.
                     */
                    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
                        if (!contains(set, value)) {
                            set._values.push(value);
                            // The value is stored at length-1, but we add 1 to all indexes
                            // and use 0 as a sentinel value
                            set._indexes[value] = set._values.length;
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Removes a value from a set. O(1).
                     *
                     * Returns true if the value was removed from the set, that is if it was present.
                     */
                    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
                        // We read and store the value's index to prevent multiple reads from the same storage slot
                        uint256 valueIndex = set._indexes[value];
                        if (valueIndex != 0) {
                            // Equivalent to contains(set, value)
                            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                            // the array, and then remove the last element (sometimes called as 'swap and pop').
                            // This modifies the order of the array, as noted in {at}.
                            uint256 toDeleteIndex = valueIndex - 1;
                            uint256 lastIndex = set._values.length - 1;
                            // The swap is only necessary if we're not removing the last element
                            if (toDeleteIndex != lastIndex) {
                                bytes32 lastValue = set._values[lastIndex];
                                // Move the last value to the index where the value to delete is
                                set._values[toDeleteIndex] = lastValue;
                                // Update the index for the moved value
                                set._indexes[lastValue] = toDeleteIndex + 1; // All indexes are 1-based
                            }
                            // Delete the slot where the moved value was stored
                            set._values.pop();
                            // Delete the index for the deleted slot
                            delete set._indexes[value];
                            return true;
                        } else {
                            return false;
                        }
                    }
                    /**
                     * @dev Returns true if the value is in the set. O(1).
                     */
                    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
                        return set._indexes[value] != 0;
                    }
                    /**
                     * @dev Returns the number of values on the set. O(1).
                     */
                    function length(Bytes32Set storage set) internal view returns (uint256) {
                        return set._values.length;
                    }
                    /**
                     * @dev Returns the value stored at position `index` in the set. O(1).
                     *
                     * Note that there are no guarantees on the ordering of values inside the
                     * array, and it may change when more values are added or removed.
                     *
                     * Requirements:
                     *
                     * - `index` must be strictly less than {length}.
                     */
                    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
                        _require(set._values.length > index, Errors.OUT_OF_BOUNDS);
                        return unchecked_at(set, index);
                    }
                    /**
                     * @dev Same as {at}, except this doesn't revert if `index` it outside of the set (i.e. if it is equal or larger
                     * than {length}). O(1).
                     *
                     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                     * within bounds.
                     */
                    // solhint-disable-next-line func-name-mixedcase
                    function unchecked_at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
                        return set._values[index];
                    }
                    function rawIndexOf(Bytes32Set storage set, bytes32 value) internal view returns (uint256) {
                        return set._indexes[value] - 1;
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the ReentrancyGuard library from OpenZeppelin Contracts, altered to reduce bytecode size.
                // Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
                // private functions, we achieve the same end result with slightly higher runtime gas costs, but reduced bytecode size.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Contract module that helps prevent reentrant calls to a function.
                 *
                 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
                 * available, which can be applied to functions to make sure there are no nested
                 * (reentrant) calls to them.
                 *
                 * Note that because there is a single `nonReentrant` guard, functions marked as
                 * `nonReentrant` may not call one another. This can be worked around by making
                 * those functions `private`, and then adding `external` `nonReentrant` entry
                 * points to them.
                 *
                 * TIP: If you would like to learn more about reentrancy and alternative ways
                 * to protect against it, check out our blog post
                 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
                 */
                abstract contract ReentrancyGuard {
                    // Booleans are more expensive than uint256 or any type that takes up a full
                    // word because each write operation emits an extra SLOAD to first read the
                    // slot's contents, replace the bits taken up by the boolean, and then write
                    // back. This is the compiler's defense against contract upgrades and
                    // pointer aliasing, and it cannot be disabled.
                    // The values being non-zero value makes deployment a bit more expensive,
                    // but in exchange the refund on every call to nonReentrant will be lower in
                    // amount. Since refunds are capped to a percentage of the total
                    // transaction's gas, it is best to keep them low in cases like this one, to
                    // increase the likelihood of the full refund coming into effect.
                    uint256 private constant _NOT_ENTERED = 1;
                    uint256 private constant _ENTERED = 2;
                    uint256 private _status;
                    constructor() {
                        _status = _NOT_ENTERED;
                    }
                    /**
                     * @dev Prevents a contract from calling itself, directly or indirectly.
                     * Calling a `nonReentrant` function from another `nonReentrant`
                     * function is not supported. It is possible to prevent this from happening
                     * by making the `nonReentrant` function external, and make it call a
                     * `private` function that does the actual work.
                     */
                    modifier nonReentrant() {
                        _enterNonReentrant();
                        _;
                        _exitNonReentrant();
                    }
                    function _enterNonReentrant() private {
                        // On the first call to nonReentrant, _status will be _NOT_ENTERED
                        _require(_status != _ENTERED, Errors.REENTRANCY);
                        // Any calls to nonReentrant after this point will fail
                        _status = _ENTERED;
                    }
                    function _exitNonReentrant() private {
                        // By storing the original value once again, a refund is triggered (see
                        // https://eips.ethereum.org/EIPS/eip-2200)
                        _status = _NOT_ENTERED;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                /**
                 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
                 * checks.
                 *
                 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
                 * easily result in undesired exploitation or bugs, since developers usually
                 * assume that overflows raise errors. `SafeCast` restores this intuition by
                 * reverting the transaction when such an operation overflows.
                 *
                 * Using this library instead of the unchecked operations eliminates an entire
                 * class of bugs, so it's recommended to use it always.
                 *
                 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
                 * all math on `uint256` and `int256` and then downcasting.
                 */
                library SafeCast {
                    /**
                     * @dev Converts an unsigned uint256 into a signed int256.
                     *
                     * Requirements:
                     *
                     * - input must be less than or equal to maxInt256.
                     */
                    function toInt256(uint256 value) internal pure returns (int256) {
                        _require(value >> 255 == 0, Errors.SAFE_CAST_VALUE_CANT_FIT_INT256);
                        return int256(value);
                    }
                    /**
                     * @dev Converts an unsigned uint256 into an unsigned uint64.
                     *
                     * Requirements:
                     *
                     * - input must be less than or equal to maxUint64.
                     */
                    function toUint64(uint256 value) internal pure returns (uint64) {
                        _require(value <= type(uint64).max, Errors.SAFE_CAST_VALUE_CANT_FIT_UINT64);
                        return uint64(value);
                    }
                }
                // SPDX-License-Identifier: MIT
                // Based on the ReentrancyGuard library from OpenZeppelin Contracts, altered to reduce gas costs.
                // The `safeTransfer` and `safeTransferFrom` functions assume that `token` is a contract (an account with code), and
                // work differently from the OpenZeppelin version if it is not.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                /**
                 * @title SafeERC20
                 * @dev Wrappers around ERC20 operations that throw on failure (when the token
                 * contract returns false). Tokens that return no value (and instead revert or
                 * throw on failure) are also supported, non-reverting calls are assumed to be
                 * successful.
                 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
                 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
                 */
                library SafeERC20 {
                    function safeApprove(
                        IERC20 token,
                        address to,
                        uint256 value
                    ) internal {
                        // Some contracts need their allowance reduced to 0 before setting it to an arbitrary amount.
                        if (value != 0 && token.allowance(address(this), address(to)) != 0) {
                            _callOptionalReturn(address(token), abi.encodeWithSelector(token.approve.selector, to, 0));
                        }
                        _callOptionalReturn(address(token), abi.encodeWithSelector(token.approve.selector, to, value));
                    }
                    function safeTransfer(
                        IERC20 token,
                        address to,
                        uint256 value
                    ) internal {
                        _callOptionalReturn(address(token), abi.encodeWithSelector(token.transfer.selector, to, value));
                    }
                    function safeTransferFrom(
                        IERC20 token,
                        address from,
                        address to,
                        uint256 value
                    ) internal {
                        _callOptionalReturn(address(token), abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                    }
                    /**
                     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                     * on the return value: the return value is optional (but if data is returned, it must not be false).
                     *
                     * WARNING: `token` is assumed to be a contract: calls to EOAs will *not* revert.
                     */
                    function _callOptionalReturn(address token, bytes memory data) private {
                        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                        // we're implementing it ourselves.
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, bytes memory returndata) = token.call(data);
                        // If the low-level call didn't succeed we return whatever was returned from it.
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            if eq(success, 0) {
                                returndatacopy(0, 0, returndatasize())
                                revert(0, returndatasize())
                            }
                        }
                        // Finally we check the returndata size is either zero or true - note that this check will always pass for EOAs
                        _require(returndata.length == 0 || abi.decode(returndata, (bool)), Errors.SAFE_ERC20_CALL_FAILED);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/misc/IWETH.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IAsset.sol";
                abstract contract AssetHelpers {
                    // solhint-disable-next-line var-name-mixedcase
                    IWETH private immutable _weth;
                    // Sentinel value used to indicate WETH with wrapping/unwrapping semantics. The zero address is a good choice for
                    // multiple reasons: it is cheap to pass as a calldata argument, it is a known invalid token and non-contract, and
                    // it is an address Pools cannot register as a token.
                    address private constant _ETH = address(0);
                    constructor(IWETH weth) {
                        _weth = weth;
                    }
                    // solhint-disable-next-line func-name-mixedcase
                    function _WETH() internal view returns (IWETH) {
                        return _weth;
                    }
                    /**
                     * @dev Returns true if `asset` is the sentinel value that represents ETH.
                     */
                    function _isETH(IAsset asset) internal pure returns (bool) {
                        return address(asset) == _ETH;
                    }
                    /**
                     * @dev Translates `asset` into an equivalent IERC20 token address. If `asset` represents ETH, it will be translated
                     * to the WETH contract.
                     */
                    function _translateToIERC20(IAsset asset) internal view returns (IERC20) {
                        return _isETH(asset) ? _WETH() : _asIERC20(asset);
                    }
                    /**
                     * @dev Same as `_translateToIERC20(IAsset)`, but for an entire array.
                     */
                    function _translateToIERC20(IAsset[] memory assets) internal view returns (IERC20[] memory) {
                        IERC20[] memory tokens = new IERC20[](assets.length);
                        for (uint256 i = 0; i < assets.length; ++i) {
                            tokens[i] = _translateToIERC20(assets[i]);
                        }
                        return tokens;
                    }
                    /**
                     * @dev Interprets `asset` as an IERC20 token. This function should only be called on `asset` if `_isETH` previously
                     * returned false for it, that is, if `asset` is guaranteed not to be the ETH sentinel value.
                     */
                    function _asIERC20(IAsset asset) internal pure returns (IERC20) {
                        return IERC20(address(asset));
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "./UserBalance.sol";
                import "./balances/BalanceAllocation.sol";
                import "./balances/GeneralPoolsBalance.sol";
                import "./balances/MinimalSwapInfoPoolsBalance.sol";
                import "./balances/TwoTokenPoolsBalance.sol";
                abstract contract AssetManagers is
                    ReentrancyGuard,
                    GeneralPoolsBalance,
                    MinimalSwapInfoPoolsBalance,
                    TwoTokenPoolsBalance
                {
                    using Math for uint256;
                    using SafeERC20 for IERC20;
                    // Stores the Asset Manager for each token of each Pool.
                    mapping(bytes32 => mapping(IERC20 => address)) internal _poolAssetManagers;
                    function managePoolBalance(PoolBalanceOp[] memory ops) external override nonReentrant whenNotPaused {
                        // This variable could be declared inside the loop, but that causes the compiler to allocate memory on each
                        // loop iteration, increasing gas costs.
                        PoolBalanceOp memory op;
                        for (uint256 i = 0; i < ops.length; ++i) {
                            // By indexing the array only once, we don't spend extra gas in the same bounds check.
                            op = ops[i];
                            bytes32 poolId = op.poolId;
                            _ensureRegisteredPool(poolId);
                            IERC20 token = op.token;
                            _require(_isTokenRegistered(poolId, token), Errors.TOKEN_NOT_REGISTERED);
                            _require(_poolAssetManagers[poolId][token] == msg.sender, Errors.SENDER_NOT_ASSET_MANAGER);
                            PoolBalanceOpKind kind = op.kind;
                            uint256 amount = op.amount;
                            (int256 cashDelta, int256 managedDelta) = _performPoolManagementOperation(kind, poolId, token, amount);
                            emit PoolBalanceManaged(poolId, msg.sender, token, cashDelta, managedDelta);
                        }
                    }
                    /**
                     * @dev Performs the `kind` Asset Manager operation on a Pool.
                     *
                     * Withdrawals will transfer `amount` tokens to the caller, deposits will transfer `amount` tokens from the caller,
                     * and updates will set the managed balance to `amount`.
                     *
                     * Returns a tuple with the 'cash' and 'managed' balance deltas as a result of this call.
                     */
                    function _performPoolManagementOperation(
                        PoolBalanceOpKind kind,
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) private returns (int256, int256) {
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (kind == PoolBalanceOpKind.WITHDRAW) {
                            return _withdrawPoolBalance(poolId, specialization, token, amount);
                        } else if (kind == PoolBalanceOpKind.DEPOSIT) {
                            return _depositPoolBalance(poolId, specialization, token, amount);
                        } else {
                            // PoolBalanceOpKind.UPDATE
                            return _updateManagedBalance(poolId, specialization, token, amount);
                        }
                    }
                    /**
                     * @dev Moves `amount` tokens from a Pool's 'cash' to 'managed' balance, and transfers them to the caller.
                     *
                     * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
                     */
                    function _withdrawPoolBalance(
                        bytes32 poolId,
                        PoolSpecialization specialization,
                        IERC20 token,
                        uint256 amount
                    ) private returns (int256 cashDelta, int256 managedDelta) {
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            _twoTokenPoolCashToManaged(poolId, token, amount);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            _minimalSwapInfoPoolCashToManaged(poolId, token, amount);
                        } else {
                            // PoolSpecialization.GENERAL
                            _generalPoolCashToManaged(poolId, token, amount);
                        }
                        if (amount > 0) {
                            token.safeTransfer(msg.sender, amount);
                        }
                        // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
                        // therefore always fit in a 256 bit integer.
                        cashDelta = int256(-amount);
                        managedDelta = int256(amount);
                    }
                    /**
                     * @dev Moves `amount` tokens from a Pool's 'managed' to 'cash' balance, and transfers them from the caller.
                     *
                     * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
                     */
                    function _depositPoolBalance(
                        bytes32 poolId,
                        PoolSpecialization specialization,
                        IERC20 token,
                        uint256 amount
                    ) private returns (int256 cashDelta, int256 managedDelta) {
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            _twoTokenPoolManagedToCash(poolId, token, amount);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            _minimalSwapInfoPoolManagedToCash(poolId, token, amount);
                        } else {
                            // PoolSpecialization.GENERAL
                            _generalPoolManagedToCash(poolId, token, amount);
                        }
                        if (amount > 0) {
                            token.safeTransferFrom(msg.sender, address(this), amount);
                        }
                        // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
                        // therefore always fit in a 256 bit integer.
                        cashDelta = int256(amount);
                        managedDelta = int256(-amount);
                    }
                    /**
                     * @dev Sets a Pool's 'managed' balance to `amount`.
                     *
                     * Returns the 'cash' and 'managed' balance deltas as a result of this call (the 'cash' delta will always be zero).
                     */
                    function _updateManagedBalance(
                        bytes32 poolId,
                        PoolSpecialization specialization,
                        IERC20 token,
                        uint256 amount
                    ) private returns (int256 cashDelta, int256 managedDelta) {
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            managedDelta = _setTwoTokenPoolManagedBalance(poolId, token, amount);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            managedDelta = _setMinimalSwapInfoPoolManagedBalance(poolId, token, amount);
                        } else {
                            // PoolSpecialization.GENERAL
                            managedDelta = _setGeneralPoolManagedBalance(poolId, token, amount);
                        }
                        cashDelta = 0;
                    }
                    /**
                     * @dev Returns true if `token` is registered for `poolId`.
                     */
                    function _isTokenRegistered(bytes32 poolId, IERC20 token) private view returns (bool) {
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            return _isTwoTokenPoolTokenRegistered(poolId, token);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            return _isMinimalSwapInfoPoolTokenRegistered(poolId, token);
                        } else {
                            // PoolSpecialization.GENERAL
                            return _isGeneralPoolTokenRegistered(poolId, token);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/misc/IWETH.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IAsset.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/Address.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "./AssetHelpers.sol";
                abstract contract AssetTransfersHandler is AssetHelpers {
                    using SafeERC20 for IERC20;
                    using Address for address payable;
                    /**
                     * @dev Receives `amount` of `asset` from `sender`. If `fromInternalBalance` is true, it first withdraws as much
                     * as possible from Internal Balance, then transfers any remaining amount.
                     *
                     * If `asset` is ETH, `fromInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
                     * will be wrapped into WETH.
                     *
                     * WARNING: this function does not check that the contract caller has actually supplied any ETH - it is up to the
                     * caller of this function to check that this is true to prevent the Vault from using its own ETH (though the Vault
                     * typically doesn't hold any).
                     */
                    function _receiveAsset(
                        IAsset asset,
                        uint256 amount,
                        address sender,
                        bool fromInternalBalance
                    ) internal {
                        if (amount == 0) {
                            return;
                        }
                        if (_isETH(asset)) {
                            _require(!fromInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
                            // The ETH amount to receive is deposited into the WETH contract, which will in turn mint WETH for
                            // the Vault at a 1:1 ratio.
                            // A check for this condition is also introduced by the compiler, but this one provides a revert reason.
                            // Note we're checking for the Vault's total balance, *not* ETH sent in this transaction.
                            _require(address(this).balance >= amount, Errors.INSUFFICIENT_ETH);
                            _WETH().deposit{ value: amount }();
                        } else {
                            IERC20 token = _asIERC20(asset);
                            if (fromInternalBalance) {
                                // We take as many tokens from Internal Balance as possible: any remaining amounts will be transferred.
                                uint256 deductedBalance = _decreaseInternalBalance(sender, token, amount, true);
                                // Because `deductedBalance` will be always the lesser of the current internal balance
                                // and the amount to decrease, it is safe to perform unchecked arithmetic.
                                amount -= deductedBalance;
                            }
                            if (amount > 0) {
                                token.safeTransferFrom(sender, address(this), amount);
                            }
                        }
                    }
                    /**
                     * @dev Sends `amount` of `asset` to `recipient`. If `toInternalBalance` is true, the asset is deposited as Internal
                     * Balance instead of being transferred.
                     *
                     * If `asset` is ETH, `toInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
                     * are instead sent directly after unwrapping WETH.
                     */
                    function _sendAsset(
                        IAsset asset,
                        uint256 amount,
                        address payable recipient,
                        bool toInternalBalance
                    ) internal {
                        if (amount == 0) {
                            return;
                        }
                        if (_isETH(asset)) {
                            // Sending ETH is not as involved as receiving it: the only special behavior is it cannot be
                            // deposited to Internal Balance.
                            _require(!toInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
                            // First, the Vault withdraws deposited ETH from the WETH contract, by burning the same amount of WETH
                            // from the Vault. This receipt will be handled by the Vault's `receive`.
                            _WETH().withdraw(amount);
                            // Then, the withdrawn ETH is sent to the recipient.
                            recipient.sendValue(amount);
                        } else {
                            IERC20 token = _asIERC20(asset);
                            if (toInternalBalance) {
                                _increaseInternalBalance(recipient, token, amount);
                            } else {
                                token.safeTransfer(recipient, amount);
                            }
                        }
                    }
                    /**
                     * @dev Returns excess ETH back to the contract caller, assuming `amountUsed` has been spent. Reverts
                     * if the caller sent less ETH than `amountUsed`.
                     *
                     * Because the caller might not know exactly how much ETH a Vault action will require, they may send extra.
                     * Note that this excess value is returned *to the contract caller* (msg.sender). If caller and e.g. swap sender are
                     * not the same (because the caller is a relayer for the sender), then it is up to the caller to manage this
                     * returned ETH.
                     */
                    function _handleRemainingEth(uint256 amountUsed) internal {
                        _require(msg.value >= amountUsed, Errors.INSUFFICIENT_ETH);
                        uint256 excess = msg.value - amountUsed;
                        if (excess > 0) {
                            msg.sender.sendValue(excess);
                        }
                    }
                    /**
                     * @dev Enables the Vault to receive ETH. This is required for it to be able to unwrap WETH, which sends ETH to the
                     * caller.
                     *
                     * Any ETH sent to the Vault outside of the WETH unwrapping mechanism would be forever locked inside the Vault, so
                     * we prevent that from happening. Other mechanisms used to send ETH to the Vault (such as being the recipient of an
                     * ETH swap, Pool exit or withdrawal, contract self-destruction, or receiving the block mining reward) will result
                     * in locked funds, but are not otherwise a security or soundness issue. This check only exists as an attempt to
                     * prevent user error.
                     */
                    receive() external payable {
                        _require(msg.sender == address(_WETH()), Errors.ETH_TRANSFER);
                    }
                    // This contract uses virtual internal functions instead of inheriting from the modules that implement them (in
                    // this case UserBalance) in order to decouple it from the rest of the system and enable standalone testing by
                    // implementing these with mocks.
                    function _increaseInternalBalance(
                        address account,
                        IERC20 token,
                        uint256 amount
                    ) internal virtual;
                    function _decreaseInternalBalance(
                        address account,
                        IERC20 token,
                        uint256 amount,
                        bool capped
                    ) internal virtual returns (uint256);
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                // This library is used to create a data structure that represents a token's balance for a Pool. 'cash' is how many
                // tokens the Pool has sitting inside of the Vault. 'managed' is how many tokens were withdrawn from the Vault by the
                // Pool's Asset Manager. 'total' is the sum of these two, and represents the Pool's total token balance, including
                // tokens that are *not* inside of the Vault.
                //
                // 'cash' is updated whenever tokens enter and exit the Vault, while 'managed' is only updated if the reason tokens are
                // moving is due to an Asset Manager action. This is reflected in the different methods available: 'increaseCash'
                // and 'decreaseCash' for swaps and add/remove liquidity events, and 'cashToManaged' and 'managedToCash' for events
                // transferring funds to and from the Asset Manager.
                //
                // The Vault disallows the Pool's 'cash' from becoming negative. In other words, it can never use any tokens that are
                // not inside the Vault.
                //
                // One of the goals of this library is to store the entire token balance in a single storage slot, which is why we use
                // 112 bit unsigned integers for 'cash' and 'managed'. For consistency, we also disallow any combination of 'cash' and
                // 'managed' that yields a 'total' that doesn't fit in 112 bits.
                //
                // The remaining 32 bits of the slot are used to store the most recent block when the total balance changed. This
                // can be used to implement price oracles that are resilient to 'sandwich' attacks.
                //
                // We could use a Solidity struct to pack these three values together in a single storage slot, but unfortunately
                // Solidity only allows for structs to live in either storage, calldata or memory. Because a memory struct still takes
                // up a slot in the stack (to store its memory location), and because the entire balance fits in a single stack slot
                // (two 112 bit values plus the 32 bit block), using memory is strictly less gas performant. Therefore, we do manual
                // packing and unpacking.
                //
                // Since we cannot define new types, we rely on bytes32 to represent these values instead, as it doesn't have any
                // associated arithmetic operations and therefore reduces the chance of misuse.
                library BalanceAllocation {
                    using Math for uint256;
                    // The 'cash' portion of the balance is stored in the least significant 112 bits of a 256 bit word, while the
                    // 'managed' part uses the following 112 bits. The most significant 32 bits are used to store the block
                    /**
                     * @dev Returns the total amount of Pool tokens, including those that are not currently in the Vault ('managed').
                     */
                    function total(bytes32 balance) internal pure returns (uint256) {
                        // Since 'cash' and 'managed' are 112 bit values, we don't need checked arithmetic. Additionally, `toBalance`
                        // ensures that 'total' always fits in 112 bits.
                        return cash(balance) + managed(balance);
                    }
                    /**
                     * @dev Returns the amount of Pool tokens currently in the Vault.
                     */
                    function cash(bytes32 balance) internal pure returns (uint256) {
                        uint256 mask = 2**(112) - 1;
                        return uint256(balance) & mask;
                    }
                    /**
                     * @dev Returns the amount of Pool tokens that are being managed by an Asset Manager.
                     */
                    function managed(bytes32 balance) internal pure returns (uint256) {
                        uint256 mask = 2**(112) - 1;
                        return uint256(balance >> 112) & mask;
                    }
                    /**
                     * @dev Returns the last block when the total balance changed.
                     */
                    function lastChangeBlock(bytes32 balance) internal pure returns (uint256) {
                        uint256 mask = 2**(32) - 1;
                        return uint256(balance >> 224) & mask;
                    }
                    /**
                     * @dev Returns the difference in 'managed' between two balances.
                     */
                    function managedDelta(bytes32 newBalance, bytes32 oldBalance) internal pure returns (int256) {
                        // Because `managed` is a 112 bit value, we can safely perform unchecked arithmetic in 256 bits.
                        return int256(managed(newBalance)) - int256(managed(oldBalance));
                    }
                    /**
                     * @dev Returns the total balance for each entry in `balances`, as well as the latest block when the total
                     * balance of *any* of them last changed.
                     */
                    function totalsAndLastChangeBlock(bytes32[] memory balances)
                        internal
                        pure
                        returns (
                            uint256[] memory results,
                            uint256 lastChangeBlock_ // Avoid shadowing
                        )
                    {
                        results = new uint256[](balances.length);
                        lastChangeBlock_ = 0;
                        for (uint256 i = 0; i < results.length; i++) {
                            bytes32 balance = balances[i];
                            results[i] = total(balance);
                            lastChangeBlock_ = Math.max(lastChangeBlock_, lastChangeBlock(balance));
                        }
                    }
                    /**
                     * @dev Returns true if `balance`'s 'total' balance is zero. Costs less gas than computing 'total' and comparing
                     * with zero.
                     */
                    function isZero(bytes32 balance) internal pure returns (bool) {
                        // We simply need to check the least significant 224 bytes of the word: the block does not affect this.
                        uint256 mask = 2**(224) - 1;
                        return (uint256(balance) & mask) == 0;
                    }
                    /**
                     * @dev Returns true if `balance`'s 'total' balance is not zero. Costs less gas than computing 'total' and comparing
                     * with zero.
                     */
                    function isNotZero(bytes32 balance) internal pure returns (bool) {
                        return !isZero(balance);
                    }
                    /**
                     * @dev Packs together `cash` and `managed` amounts with a block to create a balance value.
                     *
                     * For consistency, this also checks that the sum of `cash` and `managed` (`total`) fits in 112 bits.
                     */
                    function toBalance(
                        uint256 _cash,
                        uint256 _managed,
                        uint256 _blockNumber
                    ) internal pure returns (bytes32) {
                        uint256 _total = _cash + _managed;
                        // Since both 'cash' and 'managed' are positive integers, by checking that their sum ('total') fits in 112 bits
                        // we are also indirectly checking that both 'cash' and 'managed' themselves fit in 112 bits.
                        _require(_total >= _cash && _total < 2**112, Errors.BALANCE_TOTAL_OVERFLOW);
                        // We assume the block fits in 32 bits - this is expected to hold for at least a few decades.
                        return _pack(_cash, _managed, _blockNumber);
                    }
                    /**
                     * @dev Increases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent to the Vault (except
                     * for Asset Manager deposits).
                     *
                     * Updates the last total balance change block, even if `amount` is zero.
                     */
                    function increaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
                        uint256 newCash = cash(balance).add(amount);
                        uint256 currentManaged = managed(balance);
                        uint256 newLastChangeBlock = block.number;
                        return toBalance(newCash, currentManaged, newLastChangeBlock);
                    }
                    /**
                     * @dev Decreases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent from the Vault
                     * (except for Asset Manager withdrawals).
                     *
                     * Updates the last total balance change block, even if `amount` is zero.
                     */
                    function decreaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
                        uint256 newCash = cash(balance).sub(amount);
                        uint256 currentManaged = managed(balance);
                        uint256 newLastChangeBlock = block.number;
                        return toBalance(newCash, currentManaged, newLastChangeBlock);
                    }
                    /**
                     * @dev Moves 'cash' into 'managed', leaving 'total' unchanged. Called when an Asset Manager withdraws Pool tokens
                     * from the Vault.
                     */
                    function cashToManaged(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
                        uint256 newCash = cash(balance).sub(amount);
                        uint256 newManaged = managed(balance).add(amount);
                        uint256 currentLastChangeBlock = lastChangeBlock(balance);
                        return toBalance(newCash, newManaged, currentLastChangeBlock);
                    }
                    /**
                     * @dev Moves 'managed' into 'cash', leaving 'total' unchanged. Called when an Asset Manager deposits Pool tokens
                     * into the Vault.
                     */
                    function managedToCash(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
                        uint256 newCash = cash(balance).add(amount);
                        uint256 newManaged = managed(balance).sub(amount);
                        uint256 currentLastChangeBlock = lastChangeBlock(balance);
                        return toBalance(newCash, newManaged, currentLastChangeBlock);
                    }
                    /**
                     * @dev Sets 'managed' balance to an arbitrary value, changing 'total'. Called when the Asset Manager reports
                     * profits or losses. It's the Manager's responsibility to provide a meaningful value.
                     *
                     * Updates the last total balance change block, even if `newManaged` is equal to the current 'managed' value.
                     */
                    function setManaged(bytes32 balance, uint256 newManaged) internal view returns (bytes32) {
                        uint256 currentCash = cash(balance);
                        uint256 newLastChangeBlock = block.number;
                        return toBalance(currentCash, newManaged, newLastChangeBlock);
                    }
                    // Alternative mode for Pools with the Two Token specialization setting
                    // Instead of storing cash and external for each 'token in' a single storage slot, Two Token Pools store the cash
                    // for both tokens in the same slot, and the managed for both in another one. This reduces the gas cost for swaps,
                    // because the only slot that needs to be updated is the one with the cash. However, it also means that managing
                    // balances is more cumbersome, as both tokens need to be read/written at the same time.
                    //
                    // The field with both cash balances packed is called sharedCash, and the one with external amounts is called
                    // sharedManaged. These two are collectively called the 'shared' balance fields. In both of these, the portion
                    // that corresponds to token A is stored in the least significant 112 bits of a 256 bit word, while token B's part
                    // uses the next least significant 112 bits.
                    //
                    // Because only cash is written to during a swap, we store the last total balance change block with the
                    // packed cash fields. Typically Pools have a distinct block per token: in the case of Two Token Pools they
                    // are the same.
                    /**
                     * @dev Extracts the part of the balance that corresponds to token A. This function can be used to decode both
                     * shared cash and managed balances.
                     */
                    function _decodeBalanceA(bytes32 sharedBalance) private pure returns (uint256) {
                        uint256 mask = 2**(112) - 1;
                        return uint256(sharedBalance) & mask;
                    }
                    /**
                     * @dev Extracts the part of the balance that corresponds to token B. This function can be used to decode both
                     * shared cash and managed balances.
                     */
                    function _decodeBalanceB(bytes32 sharedBalance) private pure returns (uint256) {
                        uint256 mask = 2**(112) - 1;
                        return uint256(sharedBalance >> 112) & mask;
                    }
                    // To decode the last balance change block, we can simply use the `blockNumber` function.
                    /**
                     * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token A.
                     */
                    function fromSharedToBalanceA(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
                        // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
                        // Both token A and token B use the same block
                        return toBalance(_decodeBalanceA(sharedCash), _decodeBalanceA(sharedManaged), lastChangeBlock(sharedCash));
                    }
                    /**
                     * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token B.
                     */
                    function fromSharedToBalanceB(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
                        // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
                        // Both token A and token B use the same block
                        return toBalance(_decodeBalanceB(sharedCash), _decodeBalanceB(sharedManaged), lastChangeBlock(sharedCash));
                    }
                    /**
                     * @dev Returns the sharedCash shared field, given the current balances for token A and token B.
                     */
                    function toSharedCash(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
                        // Both balances are assigned the same block  Since it is possible a single one of them has changed (for
                        // example, in an Asset Manager update), we keep the latest (largest) one.
                        uint32 newLastChangeBlock = uint32(Math.max(lastChangeBlock(tokenABalance), lastChangeBlock(tokenBBalance)));
                        return _pack(cash(tokenABalance), cash(tokenBBalance), newLastChangeBlock);
                    }
                    /**
                     * @dev Returns the sharedManaged shared field, given the current balances for token A and token B.
                     */
                    function toSharedManaged(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
                        // We don't bother storing a last change block, as it is read from the shared cash field.
                        return _pack(managed(tokenABalance), managed(tokenBBalance), 0);
                    }
                    // Shared functions
                    /**
                     * @dev Packs together two uint112 and one uint32 into a bytes32
                     */
                    function _pack(
                        uint256 _leastSignificant,
                        uint256 _midSignificant,
                        uint256 _mostSignificant
                    ) private pure returns (bytes32) {
                        return bytes32((_mostSignificant << 224) + (_midSignificant << 112) + _leastSignificant);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/EnumerableMap.sol";
                import "./BalanceAllocation.sol";
                abstract contract GeneralPoolsBalance {
                    using BalanceAllocation for bytes32;
                    using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
                    // Data for Pools with the General specialization setting
                    //
                    // These Pools use the IGeneralPool interface, which means the Vault must query the balance for *all* of their
                    // tokens in every swap. If we kept a mapping of token to balance plus a set (array) of tokens, it'd be very gas
                    // intensive to read all token addresses just to then do a lookup on the balance mapping.
                    //
                    // Instead, we use our customized EnumerableMap, which lets us read the N balances in N+1 storage accesses (one for
                    // each token in the Pool), access the index of any 'token in' a single read (required for the IGeneralPool call),
                    // and update an entry's value given its index.
                    // Map of token -> balance pairs for each Pool with this specialization. Many functions rely on storage pointers to
                    // a Pool's EnumerableMap to save gas when computing storage slots.
                    mapping(bytes32 => EnumerableMap.IERC20ToBytes32Map) internal _generalPoolsBalances;
                    /**
                     * @dev Registers a list of tokens in a General Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokens` must not be registered in the Pool
                     * - `tokens` must not contain duplicates
                     */
                    function _registerGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            // EnumerableMaps require an explicit initial value when creating a key-value pair: we use zero, the same
                            // value that is found in uninitialized storage, which corresponds to an empty balance.
                            bool added = poolBalances.set(tokens[i], 0);
                            _require(added, Errors.TOKEN_ALREADY_REGISTERED);
                        }
                    }
                    /**
                     * @dev Deregisters a list of tokens in a General Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokens` must be registered in the Pool
                     * - `tokens` must have zero balance in the Vault
                     * - `tokens` must not contain duplicates
                     */
                    function _deregisterGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
                            _require(currentBalance.isZero(), Errors.NONZERO_TOKEN_BALANCE);
                            // We don't need to check remove's return value, since _getGeneralPoolBalance already checks that the token
                            // was registered.
                            poolBalances.remove(token);
                        }
                    }
                    /**
                     * @dev Sets the balances of a General Pool's tokens to `balances`.
                     *
                     * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
                     */
                    function _setGeneralPoolBalances(bytes32 poolId, bytes32[] memory balances) internal {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        for (uint256 i = 0; i < balances.length; ++i) {
                            // Since we assume all balances are properly ordered, we can simply use `unchecked_setAt` to avoid one less
                            // storage read per token.
                            poolBalances.unchecked_setAt(i, balances[i]);
                        }
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a General Pool from cash into managed.
                     *
                     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                     * registered for that Pool.
                     */
                    function _generalPoolCashToManaged(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateGeneralPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a General Pool from managed into cash.
                     *
                     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                     * registered for that Pool.
                     */
                    function _generalPoolManagedToCash(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateGeneralPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                    }
                    /**
                     * @dev Sets `token`'s managed balance in a General Pool to `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                     * registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _setGeneralPoolManagedBalance(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal returns (int256) {
                        return _updateGeneralPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
                    }
                    /**
                     * @dev Sets `token`'s balance in a General Pool to the result of the `mutation` function when called with the
                     * current balance and `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                     * registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _updateGeneralPoolBalance(
                        bytes32 poolId,
                        IERC20 token,
                        function(bytes32, uint256) returns (bytes32) mutation,
                        uint256 amount
                    ) private returns (int256) {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
                        bytes32 newBalance = mutation(currentBalance, amount);
                        poolBalances.set(token, newBalance);
                        return newBalance.managedDelta(currentBalance);
                    }
                    /**
                     * @dev Returns an array with all the tokens and balances in a General Pool. The order may change when tokens are
                     * registered or deregistered.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     */
                    function _getGeneralPoolTokens(bytes32 poolId)
                        internal
                        view
                        returns (IERC20[] memory tokens, bytes32[] memory balances)
                    {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        tokens = new IERC20[](poolBalances.length());
                        balances = new bytes32[](tokens.length);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            // Because the iteration is bounded by `tokens.length`, which matches the EnumerableMap's length, we can use
                            // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
                            (tokens[i], balances[i]) = poolBalances.unchecked_at(i);
                        }
                    }
                    /**
                     * @dev Returns the balance of a token in a General Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     *
                     * Requirements:
                     *
                     * - `token` must be registered in the Pool
                     */
                    function _getGeneralPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        return _getGeneralPoolBalance(poolBalances, token);
                    }
                    /**
                     * @dev Same as `_getGeneralPoolBalance` but using a Pool's storage pointer, which saves gas in repeated reads and
                     * writes.
                     */
                    function _getGeneralPoolBalance(EnumerableMap.IERC20ToBytes32Map storage poolBalances, IERC20 token)
                        private
                        view
                        returns (bytes32)
                    {
                        return poolBalances.get(token, Errors.TOKEN_NOT_REGISTERED);
                    }
                    /**
                     * @dev Returns true if `token` is registered in a General Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     */
                    function _isGeneralPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                        return poolBalances.contains(token);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/EnumerableSet.sol";
                import "./BalanceAllocation.sol";
                import "../PoolRegistry.sol";
                abstract contract MinimalSwapInfoPoolsBalance is PoolRegistry {
                    using BalanceAllocation for bytes32;
                    using EnumerableSet for EnumerableSet.AddressSet;
                    // Data for Pools with the Minimal Swap Info specialization setting
                    //
                    // These Pools use the IMinimalSwapInfoPool interface, and so the Vault must read the balance of the two tokens
                    // in the swap. The best solution is to use a mapping from token to balance, which lets us read or write any token's
                    // balance in a single storage access.
                    //
                    // We also keep a set of registered tokens. Because tokens with non-zero balance are by definition registered, in
                    // some balance getters we skip checking for token registration if a non-zero balance is found, saving gas by
                    // performing a single read instead of two.
                    mapping(bytes32 => mapping(IERC20 => bytes32)) internal _minimalSwapInfoPoolsBalances;
                    mapping(bytes32 => EnumerableSet.AddressSet) internal _minimalSwapInfoPoolsTokens;
                    /**
                     * @dev Registers a list of tokens in a Minimal Swap Info Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokens` must not be registered in the Pool
                     * - `tokens` must not contain duplicates
                     */
                    function _registerMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            bool added = poolTokens.add(address(tokens[i]));
                            _require(added, Errors.TOKEN_ALREADY_REGISTERED);
                            // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
                            // balance.
                        }
                    }
                    /**
                     * @dev Deregisters a list of tokens in a Minimal Swap Info Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokens` must be registered in the Pool
                     * - `tokens` must have zero balance in the Vault
                     * - `tokens` must not contain duplicates
                     */
                    function _deregisterMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            _require(_minimalSwapInfoPoolsBalances[poolId][token].isZero(), Errors.NONZERO_TOKEN_BALANCE);
                            // For consistency with other Pool specialization settings, we explicitly reset the balance (which may have
                            // a non-zero last change block).
                            delete _minimalSwapInfoPoolsBalances[poolId][token];
                            bool removed = poolTokens.remove(address(token));
                            _require(removed, Errors.TOKEN_NOT_REGISTERED);
                        }
                    }
                    /**
                     * @dev Sets the balances of a Minimal Swap Info Pool's tokens to `balances`.
                     *
                     * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
                     */
                    function _setMinimalSwapInfoPoolBalances(
                        bytes32 poolId,
                        IERC20[] memory tokens,
                        bytes32[] memory balances
                    ) internal {
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            _minimalSwapInfoPoolsBalances[poolId][tokens[i]] = balances[i];
                        }
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from cash into managed.
                     *
                     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                     * `token` is registered for that Pool.
                     */
                    function _minimalSwapInfoPoolCashToManaged(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from managed into cash.
                     *
                     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                     * `token` is registered for that Pool.
                     */
                    function _minimalSwapInfoPoolManagedToCash(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                    }
                    /**
                     * @dev Sets `token`'s managed balance in a Minimal Swap Info Pool to `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                     * `token` is registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _setMinimalSwapInfoPoolManagedBalance(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal returns (int256) {
                        return _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
                    }
                    /**
                     * @dev Sets `token`'s balance in a Minimal Swap Info Pool to the result of the `mutation` function when called with
                     * the current balance and `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                     * `token` is registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _updateMinimalSwapInfoPoolBalance(
                        bytes32 poolId,
                        IERC20 token,
                        function(bytes32, uint256) returns (bytes32) mutation,
                        uint256 amount
                    ) internal returns (int256) {
                        bytes32 currentBalance = _getMinimalSwapInfoPoolBalance(poolId, token);
                        bytes32 newBalance = mutation(currentBalance, amount);
                        _minimalSwapInfoPoolsBalances[poolId][token] = newBalance;
                        return newBalance.managedDelta(currentBalance);
                    }
                    /**
                     * @dev Returns an array with all the tokens and balances in a Minimal Swap Info Pool. The order may change when
                     * tokens are registered or deregistered.
                     *
                     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                     */
                    function _getMinimalSwapInfoPoolTokens(bytes32 poolId)
                        internal
                        view
                        returns (IERC20[] memory tokens, bytes32[] memory balances)
                    {
                        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                        tokens = new IERC20[](poolTokens.length());
                        balances = new bytes32[](tokens.length);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            // Because the iteration is bounded by `tokens.length`, which matches the EnumerableSet's length, we can use
                            // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
                            IERC20 token = IERC20(poolTokens.unchecked_at(i));
                            tokens[i] = token;
                            balances[i] = _minimalSwapInfoPoolsBalances[poolId][token];
                        }
                    }
                    /**
                     * @dev Returns the balance of a token in a Minimal Swap Info Pool.
                     *
                     * Requirements:
                     *
                     * - `poolId` must be a Minimal Swap Info Pool
                     * - `token` must be registered in the Pool
                     */
                    function _getMinimalSwapInfoPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                        bytes32 balance = _minimalSwapInfoPoolsBalances[poolId][token];
                        // A non-zero balance guarantees that the token is registered. If zero, we manually check if the token is
                        // registered in the Pool. Token registration implies that the Pool is registered as well, which lets us save
                        // gas by not performing the check.
                        bool tokenRegistered = balance.isNotZero() || _minimalSwapInfoPoolsTokens[poolId].contains(address(token));
                        if (!tokenRegistered) {
                            // The token might not be registered because the Pool itself is not registered. We check this to provide a
                            // more accurate revert reason.
                            _ensureRegisteredPool(poolId);
                            _revert(Errors.TOKEN_NOT_REGISTERED);
                        }
                        return balance;
                    }
                    /**
                     * @dev Returns true if `token` is registered in a Minimal Swap Info Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                     */
                    function _isMinimalSwapInfoPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                        return poolTokens.contains(address(token));
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "./BalanceAllocation.sol";
                import "../PoolRegistry.sol";
                abstract contract TwoTokenPoolsBalance is PoolRegistry {
                    using BalanceAllocation for bytes32;
                    // Data for Pools with the Two Token specialization setting
                    //
                    // These are similar to the Minimal Swap Info Pool case (because the Pool only has two tokens, and therefore there
                    // are only two balances to read), but there's a key difference in how data is stored. Keeping a set makes little
                    // sense, as it will only ever hold two tokens, so we can just store those two directly.
                    //
                    // The gas savings associated with using these Pools come from how token balances are stored: cash amounts for token
                    // A and token B are packed together, as are managed amounts. Because only cash changes in a swap, there's no need
                    // to write to this second storage slot. A single last change block number for both tokens is stored with the packed
                    // cash fields.
                    struct TwoTokenPoolBalances {
                        bytes32 sharedCash;
                        bytes32 sharedManaged;
                    }
                    // We could just keep a mapping from Pool ID to TwoTokenSharedBalances, but there's an issue: we wouldn't know to
                    // which tokens those balances correspond. This would mean having to also check which are registered with the Pool.
                    //
                    // What we do instead to save those storage reads is keep a nested mapping from the token pair hash to the balances
                    // struct. The Pool only has two tokens, so only a single entry of this mapping is set (the one that corresponds to
                    // that pair's hash).
                    //
                    // This has the trade-off of making Vault code that interacts with these Pools cumbersome: both balances must be
                    // accessed at the same time by using both token addresses, and some logic is needed to determine how the pair hash
                    // is computed. We do this by sorting the tokens, calling the token with the lowest numerical address value token A,
                    // and the other one token B. In functions where the token arguments could be either A or B, we use X and Y instead.
                    //
                    // If users query a token pair containing an unregistered token, the Pool will generate a hash for a mapping entry
                    // that was not set, and return zero balances. Non-zero balances are only possible if both tokens in the pair
                    // are registered with the Pool, which means we don't have to check the TwoTokenPoolTokens struct, and can save
                    // storage reads.
                    struct TwoTokenPoolTokens {
                        IERC20 tokenA;
                        IERC20 tokenB;
                        mapping(bytes32 => TwoTokenPoolBalances) balances;
                    }
                    mapping(bytes32 => TwoTokenPoolTokens) private _twoTokenPoolTokens;
                    /**
                     * @dev Registers tokens in a Two Token Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokenX` and `tokenY` must not be the same
                     * - The tokens must be ordered: tokenX < tokenY
                     */
                    function _registerTwoTokenPoolTokens(
                        bytes32 poolId,
                        IERC20 tokenX,
                        IERC20 tokenY
                    ) internal {
                        // Not technically true since we didn't register yet, but this is consistent with the error messages of other
                        // specialization settings.
                        _require(tokenX != tokenY, Errors.TOKEN_ALREADY_REGISTERED);
                        _require(tokenX < tokenY, Errors.UNSORTED_TOKENS);
                        // A Two Token Pool with no registered tokens is identified by having zero addresses for tokens A and B.
                        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                        _require(poolTokens.tokenA == IERC20(0) && poolTokens.tokenB == IERC20(0), Errors.TOKENS_ALREADY_SET);
                        // Since tokenX < tokenY, tokenX is A and tokenY is B
                        poolTokens.tokenA = tokenX;
                        poolTokens.tokenB = tokenY;
                        // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
                        // balance.
                    }
                    /**
                     * @dev Deregisters tokens in a Two Token Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                     *
                     * Requirements:
                     *
                     * - `tokenX` and `tokenY` must be registered in the Pool
                     * - both tokens must have zero balance in the Vault
                     */
                    function _deregisterTwoTokenPoolTokens(
                        bytes32 poolId,
                        IERC20 tokenX,
                        IERC20 tokenY
                    ) internal {
                        (
                            bytes32 balanceA,
                            bytes32 balanceB,
                            TwoTokenPoolBalances storage poolBalances
                        ) = _getTwoTokenPoolSharedBalances(poolId, tokenX, tokenY);
                        _require(balanceA.isZero() && balanceB.isZero(), Errors.NONZERO_TOKEN_BALANCE);
                        delete _twoTokenPoolTokens[poolId];
                        // For consistency with other Pool specialization settings, we explicitly reset the packed cash field (which may
                        // have a non-zero last change block).
                        delete poolBalances.sharedCash;
                    }
                    /**
                     * @dev Sets the cash balances of a Two Token Pool's tokens.
                     *
                     * WARNING: this assumes `tokenA` and `tokenB` are the Pool's two registered tokens, and are in the correct order.
                     */
                    function _setTwoTokenPoolCashBalances(
                        bytes32 poolId,
                        IERC20 tokenA,
                        bytes32 balanceA,
                        IERC20 tokenB,
                        bytes32 balanceB
                    ) internal {
                        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                        TwoTokenPoolBalances storage poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
                        poolBalances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from cash into managed.
                     *
                     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                     * registered for that Pool.
                     */
                    function _twoTokenPoolCashToManaged(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                    }
                    /**
                     * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from managed into cash.
                     *
                     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                     * registered for that Pool.
                     */
                    function _twoTokenPoolManagedToCash(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal {
                        _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                    }
                    /**
                     * @dev Sets `token`'s managed balance in a Two Token Pool to `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                     * registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _setTwoTokenPoolManagedBalance(
                        bytes32 poolId,
                        IERC20 token,
                        uint256 amount
                    ) internal returns (int256) {
                        return _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.setManaged, amount);
                    }
                    /**
                     * @dev Sets `token`'s balance in a Two Token Pool to the result of the `mutation` function when called with
                     * the current balance and `amount`.
                     *
                     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                     * registered for that Pool.
                     *
                     * Returns the managed balance delta as a result of this call.
                     */
                    function _updateTwoTokenPoolSharedBalance(
                        bytes32 poolId,
                        IERC20 token,
                        function(bytes32, uint256) returns (bytes32) mutation,
                        uint256 amount
                    ) private returns (int256) {
                        (
                            TwoTokenPoolBalances storage balances,
                            IERC20 tokenA,
                            bytes32 balanceA,
                            ,
                            bytes32 balanceB
                        ) = _getTwoTokenPoolBalances(poolId);
                        int256 delta;
                        if (token == tokenA) {
                            bytes32 newBalance = mutation(balanceA, amount);
                            delta = newBalance.managedDelta(balanceA);
                            balanceA = newBalance;
                        } else {
                            // token == tokenB
                            bytes32 newBalance = mutation(balanceB, amount);
                            delta = newBalance.managedDelta(balanceB);
                            balanceB = newBalance;
                        }
                        balances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
                        balances.sharedManaged = BalanceAllocation.toSharedManaged(balanceA, balanceB);
                        return delta;
                    }
                    /*
                     * @dev Returns an array with all the tokens and balances in a Two Token Pool. The order may change when
                     * tokens are registered or deregistered.
                     *
                     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                     */
                    function _getTwoTokenPoolTokens(bytes32 poolId)
                        internal
                        view
                        returns (IERC20[] memory tokens, bytes32[] memory balances)
                    {
                        (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
                        // Both tokens will either be zero (if unregistered) or non-zero (if registered), but we keep the full check for
                        // clarity.
                        if (tokenA == IERC20(0) || tokenB == IERC20(0)) {
                            return (new IERC20[](0), new bytes32[](0));
                        }
                        // Note that functions relying on this getter expect tokens to be properly ordered, so we use the (A, B)
                        // ordering.
                        tokens = new IERC20[](2);
                        tokens[0] = tokenA;
                        tokens[1] = tokenB;
                        balances = new bytes32[](2);
                        balances[0] = balanceA;
                        balances[1] = balanceB;
                    }
                    /**
                     * @dev Same as `_getTwoTokenPoolTokens`, except it returns the two tokens and balances directly instead of using
                     * an array, as well as a storage pointer to the `TwoTokenPoolBalances` struct, which can be used to update it
                     * without having to recompute the pair hash and storage slot.
                     */
                    function _getTwoTokenPoolBalances(bytes32 poolId)
                        private
                        view
                        returns (
                            TwoTokenPoolBalances storage poolBalances,
                            IERC20 tokenA,
                            bytes32 balanceA,
                            IERC20 tokenB,
                            bytes32 balanceB
                        )
                    {
                        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                        tokenA = poolTokens.tokenA;
                        tokenB = poolTokens.tokenB;
                        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                        poolBalances = poolTokens.balances[pairHash];
                        bytes32 sharedCash = poolBalances.sharedCash;
                        bytes32 sharedManaged = poolBalances.sharedManaged;
                        balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
                        balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
                    }
                    /**
                     * @dev Returns the balance of a token in a Two Token Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the General specialization setting.
                     *
                     * This function is convenient but not particularly gas efficient, and should be avoided during gas-sensitive
                     * operations, such as swaps. For those, _getTwoTokenPoolSharedBalances provides a more flexible interface.
                     *
                     * Requirements:
                     *
                     * - `token` must be registered in the Pool
                     */
                    function _getTwoTokenPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                        // We can't just read the balance of token, because we need to know the full pair in order to compute the pair
                        // hash and access the balance mapping. We therefore rely on `_getTwoTokenPoolBalances`.
                        (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
                        if (token == tokenA) {
                            return balanceA;
                        } else if (token == tokenB) {
                            return balanceB;
                        } else {
                            _revert(Errors.TOKEN_NOT_REGISTERED);
                        }
                    }
                    /**
                     * @dev Returns the balance of the two tokens in a Two Token Pool.
                     *
                     * The returned balances are those of token A and token B, where token A is the lowest of token X and token Y, and
                     * token B the other.
                     *
                     * This function also returns a storage pointer to the TwoTokenPoolBalances struct associated with the token pair,
                     * which can be used to update it without having to recompute the pair hash and storage slot.
                     *
                     * Requirements:
                     *
                     * - `poolId` must be a Minimal Swap Info Pool
                     * - `tokenX` and `tokenY` must be registered in the Pool
                     */
                    function _getTwoTokenPoolSharedBalances(
                        bytes32 poolId,
                        IERC20 tokenX,
                        IERC20 tokenY
                    )
                        internal
                        view
                        returns (
                            bytes32 balanceA,
                            bytes32 balanceB,
                            TwoTokenPoolBalances storage poolBalances
                        )
                    {
                        (IERC20 tokenA, IERC20 tokenB) = _sortTwoTokens(tokenX, tokenY);
                        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                        poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
                        // Because we're reading balances using the pair hash, if either token X or token Y is not registered then
                        // *both* balance entries will be zero.
                        bytes32 sharedCash = poolBalances.sharedCash;
                        bytes32 sharedManaged = poolBalances.sharedManaged;
                        // A non-zero balance guarantees that both tokens are registered. If zero, we manually check whether each
                        // token is registered in the Pool. Token registration implies that the Pool is registered as well, which
                        // lets us save gas by not performing the check.
                        bool tokensRegistered = sharedCash.isNotZero() ||
                            sharedManaged.isNotZero() ||
                            (_isTwoTokenPoolTokenRegistered(poolId, tokenA) && _isTwoTokenPoolTokenRegistered(poolId, tokenB));
                        if (!tokensRegistered) {
                            // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
                            // more accurate revert reason.
                            _ensureRegisteredPool(poolId);
                            _revert(Errors.TOKEN_NOT_REGISTERED);
                        }
                        balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
                        balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
                    }
                    /**
                     * @dev Returns true if `token` is registered in a Two Token Pool.
                     *
                     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                     */
                    function _isTwoTokenPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                        // The zero address can never be a registered token.
                        return (token == poolTokens.tokenA || token == poolTokens.tokenB) && token != IERC20(0);
                    }
                    /**
                     * @dev Returns the hash associated with a given token pair.
                     */
                    function _getTwoTokenPairHash(IERC20 tokenA, IERC20 tokenB) private pure returns (bytes32) {
                        return keccak256(abi.encodePacked(tokenA, tokenB));
                    }
                    /**
                     * @dev Sorts two tokens in ascending order, returning them as a (tokenA, tokenB) tuple.
                     */
                    function _sortTwoTokens(IERC20 tokenX, IERC20 tokenY) private pure returns (IERC20, IERC20) {
                        return tokenX < tokenY ? (tokenX, tokenY) : (tokenY, tokenX);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "./ProtocolFeesCollector.sol";
                import "./VaultAuthorization.sol";
                /**
                 * @dev To reduce the bytecode size of the Vault, most of the protocol fee logic is not here, but in the
                 * ProtocolFeesCollector contract.
                 */
                abstract contract Fees is IVault {
                    using SafeERC20 for IERC20;
                    ProtocolFeesCollector private immutable _protocolFeesCollector;
                    constructor() {
                        _protocolFeesCollector = new ProtocolFeesCollector(IVault(this));
                    }
                    function getProtocolFeesCollector() public view override returns (IProtocolFeesCollector) {
                        return _protocolFeesCollector;
                    }
                    /**
                     * @dev Returns the protocol swap fee percentage.
                     */
                    function _getProtocolSwapFeePercentage() internal view returns (uint256) {
                        return getProtocolFeesCollector().getSwapFeePercentage();
                    }
                    /**
                     * @dev Returns the protocol fee amount to charge for a flash loan of `amount`.
                     */
                    function _calculateFlashLoanFeeAmount(uint256 amount) internal view returns (uint256) {
                        // Fixed point multiplication introduces error: we round up, which means in certain scenarios the charged
                        // percentage can be slightly higher than intended.
                        uint256 percentage = getProtocolFeesCollector().getFlashLoanFeePercentage();
                        return FixedPoint.mulUp(amount, percentage);
                    }
                    function _payFeeAmount(IERC20 token, uint256 amount) internal {
                        if (amount > 0) {
                            token.safeTransfer(address(getProtocolFeesCollector()), amount);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                // This flash loan provider was based on the Aave protocol's open source
                // implementation and terminology and interfaces are intentionally kept
                // similar
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IFlashLoanRecipient.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "./Fees.sol";
                /**
                 * @dev Handles Flash Loans through the Vault. Calls the `receiveFlashLoan` hook on the flash loan recipient
                 * contract, which implements the `IFlashLoanRecipient` interface.
                 */
                abstract contract FlashLoans is Fees, ReentrancyGuard, TemporarilyPausable {
                    using SafeERC20 for IERC20;
                    function flashLoan(
                        IFlashLoanRecipient recipient,
                        IERC20[] memory tokens,
                        uint256[] memory amounts,
                        bytes memory userData
                    ) external override nonReentrant whenNotPaused {
                        InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
                        uint256[] memory feeAmounts = new uint256[](tokens.length);
                        uint256[] memory preLoanBalances = new uint256[](tokens.length);
                        // Used to ensure `tokens` is sorted in ascending order, which ensures token uniqueness.
                        IERC20 previousToken = IERC20(0);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            uint256 amount = amounts[i];
                            _require(token > previousToken, token == IERC20(0) ? Errors.ZERO_TOKEN : Errors.UNSORTED_TOKENS);
                            previousToken = token;
                            preLoanBalances[i] = token.balanceOf(address(this));
                            feeAmounts[i] = _calculateFlashLoanFeeAmount(amount);
                            _require(preLoanBalances[i] >= amount, Errors.INSUFFICIENT_FLASH_LOAN_BALANCE);
                            token.safeTransfer(address(recipient), amount);
                        }
                        recipient.receiveFlashLoan(tokens, amounts, feeAmounts, userData);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            uint256 preLoanBalance = preLoanBalances[i];
                            // Checking for loan repayment first (without accounting for fees) makes for simpler debugging, and results
                            // in more accurate revert reasons if the flash loan protocol fee percentage is zero.
                            uint256 postLoanBalance = token.balanceOf(address(this));
                            _require(postLoanBalance >= preLoanBalance, Errors.INVALID_POST_LOAN_BALANCE);
                            // No need for checked arithmetic since we know the loan was fully repaid.
                            uint256 receivedFeeAmount = postLoanBalance - preLoanBalance;
                            _require(receivedFeeAmount >= feeAmounts[i], Errors.INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT);
                            _payFeeAmount(token, receivedFeeAmount);
                            emit FlashLoan(recipient, token, amounts[i], receivedFeeAmount);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "./VaultAuthorization.sol";
                /**
                 * @dev Maintains the Pool ID data structure, implements Pool ID creation and registration, and defines useful modifiers
                 * and helper functions for ensuring correct behavior when working with Pools.
                 */
                abstract contract PoolRegistry is ReentrancyGuard, VaultAuthorization {
                    // Each pool is represented by their unique Pool ID. We use `bytes32` for them, for lack of a way to define new
                    // types.
                    mapping(bytes32 => bool) private _isPoolRegistered;
                    // We keep an increasing nonce to make Pool IDs unique. It is interpreted as a `uint80`, but storing it as a
                    // `uint256` results in reduced bytecode on reads and writes due to the lack of masking.
                    uint256 private _nextPoolNonce;
                    /**
                     * @dev Reverts unless `poolId` corresponds to a registered Pool.
                     */
                    modifier withRegisteredPool(bytes32 poolId) {
                        _ensureRegisteredPool(poolId);
                        _;
                    }
                    /**
                     * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
                     */
                    modifier onlyPool(bytes32 poolId) {
                        _ensurePoolIsSender(poolId);
                        _;
                    }
                    /**
                     * @dev Reverts unless `poolId` corresponds to a registered Pool.
                     */
                    function _ensureRegisteredPool(bytes32 poolId) internal view {
                        _require(_isPoolRegistered[poolId], Errors.INVALID_POOL_ID);
                    }
                    /**
                     * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
                     */
                    function _ensurePoolIsSender(bytes32 poolId) private view {
                        _ensureRegisteredPool(poolId);
                        _require(msg.sender == _getPoolAddress(poolId), Errors.CALLER_NOT_POOL);
                    }
                    function registerPool(PoolSpecialization specialization)
                        external
                        override
                        nonReentrant
                        whenNotPaused
                        returns (bytes32)
                    {
                        // Each Pool is assigned a unique ID based on an incrementing nonce. This assumes there will never be more than
                        // 2**80 Pools, and the nonce will not overflow.
                        bytes32 poolId = _toPoolId(msg.sender, specialization, uint80(_nextPoolNonce));
                        _require(!_isPoolRegistered[poolId], Errors.INVALID_POOL_ID); // Should never happen as Pool IDs are unique.
                        _isPoolRegistered[poolId] = true;
                        _nextPoolNonce += 1;
                        // Note that msg.sender is the pool's contract
                        emit PoolRegistered(poolId, msg.sender, specialization);
                        return poolId;
                    }
                    function getPool(bytes32 poolId)
                        external
                        view
                        override
                        withRegisteredPool(poolId)
                        returns (address, PoolSpecialization)
                    {
                        return (_getPoolAddress(poolId), _getPoolSpecialization(poolId));
                    }
                    /**
                     * @dev Creates a Pool ID.
                     *
                     * These are deterministically created by packing the Pool's contract address and its specialization setting into
                     * the ID. This saves gas by making this data easily retrievable from a Pool ID with no storage accesses.
                     *
                     * Since a single contract can register multiple Pools, a unique nonce must be provided to ensure Pool IDs are
                     * unique.
                     *
                     * Pool IDs have the following layout:
                     * | 20 bytes pool contract address | 2 bytes specialization setting | 10 bytes nonce |
                     * MSB                                                                              LSB
                     *
                     * 2 bytes for the specialization setting is a bit overkill: there only three of them, which means two bits would
                     * suffice. However, there's nothing else of interest to store in this extra space.
                     */
                    function _toPoolId(
                        address pool,
                        PoolSpecialization specialization,
                        uint80 nonce
                    ) internal pure returns (bytes32) {
                        bytes32 serialized;
                        serialized |= bytes32(uint256(nonce));
                        serialized |= bytes32(uint256(specialization)) << (10 * 8);
                        serialized |= bytes32(uint256(pool)) << (12 * 8);
                        return serialized;
                    }
                    /**
                     * @dev Returns the address of a Pool's contract.
                     *
                     * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
                     */
                    function _getPoolAddress(bytes32 poolId) internal pure returns (address) {
                        // 12 byte logical shift left to remove the nonce and specialization setting. We don't need to mask,
                        // since the logical shift already sets the upper bits to zero.
                        return address(uint256(poolId) >> (12 * 8));
                    }
                    /**
                     * @dev Returns the specialization setting of a Pool.
                     *
                     * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
                     */
                    function _getPoolSpecialization(bytes32 poolId) internal pure returns (PoolSpecialization specialization) {
                        // 10 byte logical shift left to remove the nonce, followed by a 2 byte mask to remove the address.
                        uint256 value = uint256(poolId >> (10 * 8)) & (2**(2 * 8) - 1);
                        // Casting a value into an enum results in a runtime check that reverts unless the value is within the enum's
                        // range. Passing an invalid Pool ID to this function would then result in an obscure revert with no reason
                        // string: we instead perform the check ourselves to help in error diagnosis.
                        // There are three Pool specialization settings: general, minimal swap info and two tokens, which correspond to
                        // values 0, 1 and 2.
                        _require(value < 3, Errors.INVALID_POOL_ID);
                        // Because we have checked that `value` is within the enum range, we can use assembly to skip the runtime check.
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            specialization := value
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "./AssetManagers.sol";
                import "./PoolRegistry.sol";
                import "./balances/BalanceAllocation.sol";
                abstract contract PoolTokens is ReentrancyGuard, PoolRegistry, AssetManagers {
                    using BalanceAllocation for bytes32;
                    using BalanceAllocation for bytes32[];
                    function registerTokens(
                        bytes32 poolId,
                        IERC20[] memory tokens,
                        address[] memory assetManagers
                    ) external override nonReentrant whenNotPaused onlyPool(poolId) {
                        InputHelpers.ensureInputLengthMatch(tokens.length, assetManagers.length);
                        // Validates token addresses and assigns Asset Managers
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            _require(token != IERC20(0), Errors.INVALID_TOKEN);
                            _poolAssetManagers[poolId][token] = assetManagers[i];
                        }
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
                            _registerTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            _registerMinimalSwapInfoPoolTokens(poolId, tokens);
                        } else {
                            // PoolSpecialization.GENERAL
                            _registerGeneralPoolTokens(poolId, tokens);
                        }
                        emit TokensRegistered(poolId, tokens, assetManagers);
                    }
                    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens)
                        external
                        override
                        nonReentrant
                        whenNotPaused
                        onlyPool(poolId)
                    {
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
                            _deregisterTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            _deregisterMinimalSwapInfoPoolTokens(poolId, tokens);
                        } else {
                            // PoolSpecialization.GENERAL
                            _deregisterGeneralPoolTokens(poolId, tokens);
                        }
                        // The deregister calls above ensure the total token balance is zero. Therefore it is now safe to remove any
                        // associated Asset Managers, since they hold no Pool balance.
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            delete _poolAssetManagers[poolId][tokens[i]];
                        }
                        emit TokensDeregistered(poolId, tokens);
                    }
                    function getPoolTokens(bytes32 poolId)
                        external
                        view
                        override
                        withRegisteredPool(poolId)
                        returns (
                            IERC20[] memory tokens,
                            uint256[] memory balances,
                            uint256 lastChangeBlock
                        )
                    {
                        bytes32[] memory rawBalances;
                        (tokens, rawBalances) = _getPoolTokens(poolId);
                        (balances, lastChangeBlock) = rawBalances.totalsAndLastChangeBlock();
                    }
                    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                        external
                        view
                        override
                        withRegisteredPool(poolId)
                        returns (
                            uint256 cash,
                            uint256 managed,
                            uint256 lastChangeBlock,
                            address assetManager
                        )
                    {
                        bytes32 balance;
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            balance = _getTwoTokenPoolBalance(poolId, token);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            balance = _getMinimalSwapInfoPoolBalance(poolId, token);
                        } else {
                            // PoolSpecialization.GENERAL
                            balance = _getGeneralPoolBalance(poolId, token);
                        }
                        cash = balance.cash();
                        managed = balance.managed();
                        lastChangeBlock = balance.lastChangeBlock();
                        assetManager = _poolAssetManagers[poolId][token];
                    }
                    /**
                     * @dev Returns all of `poolId`'s registered tokens, along with their raw balances.
                     */
                    function _getPoolTokens(bytes32 poolId) internal view returns (IERC20[] memory tokens, bytes32[] memory balances) {
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            return _getTwoTokenPoolTokens(poolId);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            return _getMinimalSwapInfoPoolTokens(poolId);
                        } else {
                            // PoolSpecialization.GENERAL
                            return _getGeneralPoolTokens(poolId);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/vault/IProtocolFeesCollector.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/Authentication.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                /**
                 * @dev This an auxiliary contract to the Vault, deployed by it during construction. It offloads some of the tasks the
                 * Vault performs to reduce its overall bytecode size.
                 *
                 * The current values for all protocol fee percentages are stored here, and any tokens charged as protocol fees are
                 * sent to this contract, where they may be withdrawn by authorized entities. All authorization tasks are delegated
                 * to the Vault's own authorizer.
                 */
                contract ProtocolFeesCollector is IProtocolFeesCollector, Authentication, ReentrancyGuard {
                    using SafeERC20 for IERC20;
                    // Absolute maximum fee percentages (1e18 = 100%, 1e16 = 1%).
                    uint256 private constant _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE = 50e16; // 50%
                    uint256 private constant _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE = 1e16; // 1%
                    IVault public immutable override vault;
                    // All fee percentages are 18-decimal fixed point numbers.
                    // The swap fee is charged whenever a swap occurs, as a percentage of the fee charged by the Pool. These are not
                    // actually charged on each individual swap: the `Vault` relies on the Pools being honest and reporting fees due
                    // when users join and exit them.
                    uint256 private _swapFeePercentage;
                    // The flash loan fee is charged whenever a flash loan occurs, as a percentage of the tokens lent.
                    uint256 private _flashLoanFeePercentage;
                    constructor(IVault _vault)
                        // The ProtocolFeesCollector is a singleton, so it simply uses its own address to disambiguate action
                        // identifiers.
                        Authentication(bytes32(uint256(address(this))))
                    {
                        vault = _vault;
                    }
                    function withdrawCollectedFees(
                        IERC20[] calldata tokens,
                        uint256[] calldata amounts,
                        address recipient
                    ) external override nonReentrant authenticate {
                        InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            IERC20 token = tokens[i];
                            uint256 amount = amounts[i];
                            token.safeTransfer(recipient, amount);
                        }
                    }
                    function setSwapFeePercentage(uint256 newSwapFeePercentage) external override authenticate {
                        _require(newSwapFeePercentage <= _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE, Errors.SWAP_FEE_PERCENTAGE_TOO_HIGH);
                        _swapFeePercentage = newSwapFeePercentage;
                        emit SwapFeePercentageChanged(newSwapFeePercentage);
                    }
                    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external override authenticate {
                        _require(
                            newFlashLoanFeePercentage <= _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE,
                            Errors.FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH
                        );
                        _flashLoanFeePercentage = newFlashLoanFeePercentage;
                        emit FlashLoanFeePercentageChanged(newFlashLoanFeePercentage);
                    }
                    function getSwapFeePercentage() external view override returns (uint256) {
                        return _swapFeePercentage;
                    }
                    function getFlashLoanFeePercentage() external view override returns (uint256) {
                        return _flashLoanFeePercentage;
                    }
                    function getCollectedFeeAmounts(IERC20[] memory tokens)
                        external
                        view
                        override
                        returns (uint256[] memory feeAmounts)
                    {
                        feeAmounts = new uint256[](tokens.length);
                        for (uint256 i = 0; i < tokens.length; ++i) {
                            feeAmounts[i] = tokens[i].balanceOf(address(this));
                        }
                    }
                    function getAuthorizer() external view override returns (IAuthorizer) {
                        return _getAuthorizer();
                    }
                    function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
                        return _getAuthorizer().canPerform(actionId, account, address(this));
                    }
                    function _getAuthorizer() internal view returns (IAuthorizer) {
                        return vault.getAuthorizer();
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeCast.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "./AssetTransfersHandler.sol";
                import "./VaultAuthorization.sol";
                /**
                 * Implement User Balance interactions, which combine Internal Balance and using the Vault's ERC20 allowance.
                 *
                 * Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
                 * transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
                 * when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
                 * gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
                 *
                 * Internal Balance management features batching, which means a single contract call can be used to perform multiple
                 * operations of different kinds, with different senders and recipients, at once.
                 */
                abstract contract UserBalance is ReentrancyGuard, AssetTransfersHandler, VaultAuthorization {
                    using Math for uint256;
                    using SafeCast for uint256;
                    using SafeERC20 for IERC20;
                    // Internal Balance for each token, for each account.
                    mapping(address => mapping(IERC20 => uint256)) private _internalTokenBalance;
                    function getInternalBalance(address user, IERC20[] memory tokens)
                        external
                        view
                        override
                        returns (uint256[] memory balances)
                    {
                        balances = new uint256[](tokens.length);
                        for (uint256 i = 0; i < tokens.length; i++) {
                            balances[i] = _getInternalBalance(user, tokens[i]);
                        }
                    }
                    function manageUserBalance(UserBalanceOp[] memory ops) external payable override nonReentrant {
                        // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
                        uint256 ethWrapped = 0;
                        // Cache for these checks so we only perform them once (if at all).
                        bool checkedCallerIsRelayer = false;
                        bool checkedNotPaused = false;
                        for (uint256 i = 0; i < ops.length; i++) {
                            UserBalanceOpKind kind;
                            IAsset asset;
                            uint256 amount;
                            address sender;
                            address payable recipient;
                            // This destructuring by calling `_validateUserBalanceOp` seems odd, but results in reduced bytecode size.
                            (kind, asset, amount, sender, recipient, checkedCallerIsRelayer) = _validateUserBalanceOp(
                                ops[i],
                                checkedCallerIsRelayer
                            );
                            if (kind == UserBalanceOpKind.WITHDRAW_INTERNAL) {
                                // Internal Balance withdrawals can always be performed by an authorized account.
                                _withdrawFromInternalBalance(asset, sender, recipient, amount);
                            } else {
                                // All other operations are blocked if the contract is paused.
                                // We cache the result of the pause check and skip it for other operations in this same transaction
                                // (if any).
                                if (!checkedNotPaused) {
                                    _ensureNotPaused();
                                    checkedNotPaused = true;
                                }
                                if (kind == UserBalanceOpKind.DEPOSIT_INTERNAL) {
                                    _depositToInternalBalance(asset, sender, recipient, amount);
                                    // Keep track of all ETH wrapped into WETH as part of a deposit.
                                    if (_isETH(asset)) {
                                        ethWrapped = ethWrapped.add(amount);
                                    }
                                } else {
                                    // Transfers don't support ETH.
                                    _require(!_isETH(asset), Errors.CANNOT_USE_ETH_SENTINEL);
                                    IERC20 token = _asIERC20(asset);
                                    if (kind == UserBalanceOpKind.TRANSFER_INTERNAL) {
                                        _transferInternalBalance(token, sender, recipient, amount);
                                    } else {
                                        // TRANSFER_EXTERNAL
                                        _transferToExternalBalance(token, sender, recipient, amount);
                                    }
                                }
                            }
                        }
                        // Handle any remaining ETH.
                        _handleRemainingEth(ethWrapped);
                    }
                    function _depositToInternalBalance(
                        IAsset asset,
                        address sender,
                        address recipient,
                        uint256 amount
                    ) private {
                        _increaseInternalBalance(recipient, _translateToIERC20(asset), amount);
                        _receiveAsset(asset, amount, sender, false);
                    }
                    function _withdrawFromInternalBalance(
                        IAsset asset,
                        address sender,
                        address payable recipient,
                        uint256 amount
                    ) private {
                        // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
                        _decreaseInternalBalance(sender, _translateToIERC20(asset), amount, false);
                        _sendAsset(asset, amount, recipient, false);
                    }
                    function _transferInternalBalance(
                        IERC20 token,
                        address sender,
                        address recipient,
                        uint256 amount
                    ) private {
                        // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
                        _decreaseInternalBalance(sender, token, amount, false);
                        _increaseInternalBalance(recipient, token, amount);
                    }
                    function _transferToExternalBalance(
                        IERC20 token,
                        address sender,
                        address recipient,
                        uint256 amount
                    ) private {
                        if (amount > 0) {
                            token.safeTransferFrom(sender, recipient, amount);
                            emit ExternalBalanceTransfer(token, sender, recipient, amount);
                        }
                    }
                    /**
                     * @dev Increases `account`'s Internal Balance for `token` by `amount`.
                     */
                    function _increaseInternalBalance(
                        address account,
                        IERC20 token,
                        uint256 amount
                    ) internal override {
                        uint256 currentBalance = _getInternalBalance(account, token);
                        uint256 newBalance = currentBalance.add(amount);
                        _setInternalBalance(account, token, newBalance, amount.toInt256());
                    }
                    /**
                     * @dev Decreases `account`'s Internal Balance for `token` by `amount`. If `allowPartial` is true, this function
                     * doesn't revert if `account` doesn't have enough balance, and sets it to zero and returns the deducted amount
                     * instead.
                     */
                    function _decreaseInternalBalance(
                        address account,
                        IERC20 token,
                        uint256 amount,
                        bool allowPartial
                    ) internal override returns (uint256 deducted) {
                        uint256 currentBalance = _getInternalBalance(account, token);
                        _require(allowPartial || (currentBalance >= amount), Errors.INSUFFICIENT_INTERNAL_BALANCE);
                        deducted = Math.min(currentBalance, amount);
                        // By construction, `deducted` is lower or equal to `currentBalance`, so we don't need to use checked
                        // arithmetic.
                        uint256 newBalance = currentBalance - deducted;
                        _setInternalBalance(account, token, newBalance, -(deducted.toInt256()));
                    }
                    /**
                     * @dev Sets `account`'s Internal Balance for `token` to `newBalance`.
                     *
                     * Emits an `InternalBalanceChanged` event. This event includes `delta`, which is the amount the balance increased
                     * (if positive) or decreased (if negative). To avoid reading the current balance in order to compute the delta,
                     * this function relies on the caller providing it directly.
                     */
                    function _setInternalBalance(
                        address account,
                        IERC20 token,
                        uint256 newBalance,
                        int256 delta
                    ) private {
                        _internalTokenBalance[account][token] = newBalance;
                        emit InternalBalanceChanged(account, token, delta);
                    }
                    /**
                     * @dev Returns `account`'s Internal Balance for `token`.
                     */
                    function _getInternalBalance(address account, IERC20 token) internal view returns (uint256) {
                        return _internalTokenBalance[account][token];
                    }
                    /**
                     * @dev Destructures a User Balance operation, validating that the contract caller is allowed to perform it.
                     */
                    function _validateUserBalanceOp(UserBalanceOp memory op, bool checkedCallerIsRelayer)
                        private
                        view
                        returns (
                            UserBalanceOpKind,
                            IAsset,
                            uint256,
                            address,
                            address payable,
                            bool
                        )
                    {
                        // The only argument we need to validate is `sender`, which can only be either the contract caller, or a
                        // relayer approved by `sender`.
                        address sender = op.sender;
                        if (sender != msg.sender) {
                            // We need to check both that the contract caller is a relayer, and that `sender` approved them.
                            // Because the relayer check is global (i.e. independent of `sender`), we cache that result and skip it for
                            // other operations in this same transaction (if any).
                            if (!checkedCallerIsRelayer) {
                                _authenticateCaller();
                                checkedCallerIsRelayer = true;
                            }
                            _require(_hasApprovedRelayer(sender, msg.sender), Errors.USER_DOESNT_ALLOW_RELAYER);
                        }
                        return (op.kind, op.asset, op.amount, sender, op.recipient, checkedCallerIsRelayer);
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/Authentication.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/ExtraCalldataEOASignaturesValidator.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/TemporarilyPausable.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                /**
                 * @dev Manages access control of Vault permissioned functions by relying on the Authorizer and signature validation.
                 *
                 * Additionally handles relayer access and approval.
                 */
                abstract contract VaultAuthorization is
                    IVault,
                    ReentrancyGuard,
                    Authentication,
                    ExtraCalldataEOASignaturesValidator,
                    TemporarilyPausable
                {
                    // Ideally, we'd store the type hashes as immutable state variables to avoid computing the hash at runtime, but
                    // unfortunately immutable variables cannot be used in assembly, so we just keep the precomputed hashes instead.
                    // _JOIN_TYPE_HASH = keccak256("JoinPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                    bytes32 private constant _JOIN_TYPE_HASH = 0x3f7b71252bd19113ff48c19c6e004a9bcfcca320a0d74d58e85877cbd7dcae58;
                    // _EXIT_TYPE_HASH = keccak256("ExitPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                    bytes32 private constant _EXIT_TYPE_HASH = 0x8bbc57f66ea936902f50a71ce12b92c43f3c5340bb40c27c4e90ab84eeae3353;
                    // _SWAP_TYPE_HASH = keccak256("Swap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                    bytes32 private constant _SWAP_TYPE_HASH = 0xe192dcbc143b1e244ad73b813fd3c097b832ad260a157340b4e5e5beda067abe;
                    // _BATCH_SWAP_TYPE_HASH = keccak256("BatchSwap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                    bytes32 private constant _BATCH_SWAP_TYPE_HASH = 0x9bfc43a4d98313c6766986ffd7c916c7481566d9f224c6819af0a53388aced3a;
                    // _SET_RELAYER_TYPE_HASH =
                    //     keccak256("SetRelayerApproval(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                    bytes32
                        private constant _SET_RELAYER_TYPE_HASH = 0xa3f865aa351e51cfeb40f5178d1564bb629fe9030b83caf6361d1baaf5b90b5a;
                    IAuthorizer private _authorizer;
                    mapping(address => mapping(address => bool)) private _approvedRelayers;
                    /**
                     * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call this function (that
                     * is, it is a relayer for that function), and either:
                     *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
                     *  b) a valid signature from them was appended to the calldata.
                     *
                     * Should only be applied to external functions.
                     */
                    modifier authenticateFor(address user) {
                        _authenticateFor(user);
                        _;
                    }
                    constructor(IAuthorizer authorizer)
                        // The Vault is a singleton, so it simply uses its own address to disambiguate action identifiers.
                        Authentication(bytes32(uint256(address(this))))
                        EIP712("Balancer V2 Vault", "1")
                    {
                        _setAuthorizer(authorizer);
                    }
                    function setAuthorizer(IAuthorizer newAuthorizer) external override nonReentrant authenticate {
                        _setAuthorizer(newAuthorizer);
                    }
                    function _setAuthorizer(IAuthorizer newAuthorizer) private {
                        emit AuthorizerChanged(newAuthorizer);
                        _authorizer = newAuthorizer;
                    }
                    function getAuthorizer() external view override returns (IAuthorizer) {
                        return _authorizer;
                    }
                    function setRelayerApproval(
                        address sender,
                        address relayer,
                        bool approved
                    ) external override nonReentrant whenNotPaused authenticateFor(sender) {
                        _approvedRelayers[sender][relayer] = approved;
                        emit RelayerApprovalChanged(relayer, sender, approved);
                    }
                    function hasApprovedRelayer(address user, address relayer) external view override returns (bool) {
                        return _hasApprovedRelayer(user, relayer);
                    }
                    /**
                     * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call the entry point
                     * function (that is, it is a relayer for that function) and either:
                     *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
                     *  b) a valid signature from them was appended to the calldata.
                     */
                    function _authenticateFor(address user) internal {
                        if (msg.sender != user) {
                            // In this context, 'permission to call a function' means 'being a relayer for a function'.
                            _authenticateCaller();
                            // Being a relayer is not sufficient: `user` must have also approved the caller either via
                            // `setRelayerApproval`, or by providing a signature appended to the calldata.
                            if (!_hasApprovedRelayer(user, msg.sender)) {
                                _validateExtraCalldataSignature(user, Errors.USER_DOESNT_ALLOW_RELAYER);
                            }
                        }
                    }
                    /**
                     * @dev Returns true if `user` approved `relayer` to act as a relayer for them.
                     */
                    function _hasApprovedRelayer(address user, address relayer) internal view returns (bool) {
                        return _approvedRelayers[user][relayer];
                    }
                    function _canPerform(bytes32 actionId, address user) internal view override returns (bool) {
                        // Access control is delegated to the Authorizer.
                        return _authorizer.canPerform(actionId, user, address(this));
                    }
                    function _entrypointTypeHash() internal pure override returns (bytes32 hash) {
                        // This is a simple switch-case statement, trivially written in Solidity by chaining else-if statements, but the
                        // assembly implementation results in much denser bytecode.
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // The function selector is located at the first 4 bytes of calldata. We copy the first full calldata
                            // 256 word, and then perform a logical shift to the right, moving the selector to the least significant
                            // 4 bytes.
                            let selector := shr(224, calldataload(0))
                            // With the selector in the least significant 4 bytes, we can use 4 byte literals with leading zeros,
                            // resulting in dense bytecode (PUSH4 opcodes).
                            switch selector
                                case 0xb95cac28 {
                                    hash := _JOIN_TYPE_HASH
                                }
                                case 0x8bdb3913 {
                                    hash := _EXIT_TYPE_HASH
                                }
                                case 0x52bbbe29 {
                                    hash := _SWAP_TYPE_HASH
                                }
                                case 0x945bcec9 {
                                    hash := _BATCH_SWAP_TYPE_HASH
                                }
                                case 0xfa6e671d {
                                    hash := _SET_RELAYER_TYPE_HASH
                                }
                                default {
                                    hash := 0x0000000000000000000000000000000000000000000000000000000000000000
                                }
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IBasePool.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "@balancer-labs/v2-vault/contracts/Fees.sol";
                import "@balancer-labs/v2-vault/contracts/PoolTokens.sol";
                import "@balancer-labs/v2-vault/contracts/UserBalance.sol";
                /**
                 * @dev Stores the Asset Managers (by Pool and token), and implements the top level Asset Manager and Pool interfaces,
                 * such as registering and deregistering tokens, joining and exiting Pools, and informational functions like `getPool`
                 * and `getPoolTokens`, delegating to specialization-specific functions as needed.
                 *
                 * `managePoolBalance` handles all Asset Manager interactions.
                 */
                abstract contract PoolBalances is Fees, ReentrancyGuard, PoolTokens, UserBalance {
                    using Math for uint256;
                    using SafeERC20 for IERC20;
                    using BalanceAllocation for bytes32;
                    using BalanceAllocation for bytes32[];
                    function joinPool(
                        bytes32 poolId,
                        address sender,
                        address recipient,
                        JoinPoolRequest memory request
                    ) external payable override whenNotPaused {
                        // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
                        // Note that `recipient` is not actually payable in the context of a join - we cast it because we handle both
                        // joins and exits at once.
                        _joinOrExit(PoolBalanceChangeKind.JOIN, poolId, sender, payable(recipient), _toPoolBalanceChange(request));
                    }
                    function exitPool(
                        bytes32 poolId,
                        address sender,
                        address payable recipient,
                        ExitPoolRequest memory request
                    ) external override {
                        // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
                        _joinOrExit(PoolBalanceChangeKind.EXIT, poolId, sender, recipient, _toPoolBalanceChange(request));
                    }
                    // This has the exact same layout as JoinPoolRequest and ExitPoolRequest, except the `maxAmountsIn` and
                    // `minAmountsOut` are called `limits`. Internally we use this struct for both since these two functions are quite
                    // similar, but expose the others to callers for clarity.
                    struct PoolBalanceChange {
                        IAsset[] assets;
                        uint256[] limits;
                        bytes userData;
                        bool useInternalBalance;
                    }
                    /**
                     * @dev Converts a JoinPoolRequest into a PoolBalanceChange, with no runtime cost.
                     */
                    function _toPoolBalanceChange(JoinPoolRequest memory request)
                        private
                        pure
                        returns (PoolBalanceChange memory change)
                    {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            change := request
                        }
                    }
                    /**
                     * @dev Converts an ExitPoolRequest into a PoolBalanceChange, with no runtime cost.
                     */
                    function _toPoolBalanceChange(ExitPoolRequest memory request)
                        private
                        pure
                        returns (PoolBalanceChange memory change)
                    {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            change := request
                        }
                    }
                    /**
                     * @dev Implements both `joinPool` and `exitPool`, based on `kind`.
                     */
                    function _joinOrExit(
                        PoolBalanceChangeKind kind,
                        bytes32 poolId,
                        address sender,
                        address payable recipient,
                        PoolBalanceChange memory change
                    ) private nonReentrant withRegisteredPool(poolId) authenticateFor(sender) {
                        // This function uses a large number of stack variables (poolId, sender and recipient, balances, amounts, fees,
                        // etc.), which leads to 'stack too deep' issues. It relies on private functions with seemingly arbitrary
                        // interfaces to work around this limitation.
                        InputHelpers.ensureInputLengthMatch(change.assets.length, change.limits.length);
                        // We first check that the caller passed the Pool's registered tokens in the correct order, and retrieve the
                        // current balance for each.
                        IERC20[] memory tokens = _translateToIERC20(change.assets);
                        bytes32[] memory balances = _validateTokensAndGetBalances(poolId, tokens);
                        // The corresponding Pool hook is called to get the amounts in/out plus protocol fee amounts.
                        (
                            uint256[] memory amountsInOrOut,
                            uint256[] memory dueProtocolFeeAmounts
                        ) = _callPoolBalanceChange(kind, poolId, sender, recipient, change, balances);
                        // We update the Pool balances based on the amounts in/out and fees paid.
                        _updatePoolBalances(kind, poolId, sender, change, tokens, balances, amountsInOrOut, dueProtocolFeeAmounts);
                       
                        // We handle the necessary transfers and fee payments. 
                        kind == PoolBalanceChangeKind.JOIN
                            ? _processJoinPoolTransfers(sender, change, balances, amountsInOrOut, dueProtocolFeeAmounts)
                            : _processExitPoolTransfers(recipient, change, balances, amountsInOrOut, dueProtocolFeeAmounts);
                    }
                    /**
                     * @dev Calls the corresponding Pool hook to get the amounts in/out plus protocol fee amounts, and returns them.
                     */
                    function _callPoolBalanceChange(
                        PoolBalanceChangeKind kind,
                        bytes32 poolId,
                        address sender,
                        address payable recipient,
                        PoolBalanceChange memory change,
                        bytes32[] memory balances
                    )
                        private
                        returns (
                            uint256[] memory amountsInOrOut,
                            uint256[] memory dueProtocolFeeAmounts
                        )
                    {
                        (uint256[] memory totalBalances, uint256 lastChangeBlock) = balances.totalsAndLastChangeBlock();
                        IBasePool pool = IBasePool(_getPoolAddress(poolId));
                        (amountsInOrOut, dueProtocolFeeAmounts) = kind == PoolBalanceChangeKind.JOIN
                            ? pool.onJoinPool(
                                poolId,
                                sender,
                                recipient,
                                totalBalances,
                                lastChangeBlock,
                                _getProtocolSwapFeePercentage(),
                                change.userData
                            )
                            : pool.onExitPool(
                                poolId,
                                sender,
                                recipient,
                                totalBalances,
                                lastChangeBlock,
                                _getProtocolSwapFeePercentage(),
                                change.userData
                            );
                        InputHelpers.ensureInputLengthMatch(balances.length, amountsInOrOut.length, dueProtocolFeeAmounts.length);
                    }
                    /**
                     * @dev Updates the Pool balances based on the amounts in/out and fees paid.
                     */
                    function _updatePoolBalances(
                        PoolBalanceChangeKind kind,
                        bytes32 poolId,
                        address sender,
                        PoolBalanceChange memory change,
                        IERC20[] memory tokens,
                        bytes32[] memory balances,
                        uint256[] memory amountsInOrOut,
                        uint256[] memory dueProtocolFeeAmounts
                    ) private {
                        bytes32[] memory finalBalances = kind == PoolBalanceChangeKind.JOIN
                            ? _computeJoinPoolFinalBalances(balances, change.limits, amountsInOrOut, dueProtocolFeeAmounts)
                            : _computeExitPoolFinalBalances(balances, change.limits, amountsInOrOut, dueProtocolFeeAmounts);
                        // Storing the new Pool balances.
                        PoolSpecialization specialization = _getPoolSpecialization(poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            _setTwoTokenPoolCashBalances(poolId, tokens[0], finalBalances[0], tokens[1], finalBalances[1]);
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            _setMinimalSwapInfoPoolBalances(poolId, tokens, finalBalances);
                        } else {
                            // PoolSpecialization.GENERAL
                            _setGeneralPoolBalances(poolId, finalBalances);
                        }
                        bool positive = kind == PoolBalanceChangeKind.JOIN; // Amounts in are positive, out are negative
                        emit PoolBalanceChanged(
                            poolId,
                            sender,
                            tokens,
                            // We can unsafely cast to int256 because balances are actually stored as uint112
                            _unsafeCastToInt256(amountsInOrOut, positive),
                            dueProtocolFeeAmounts
                        );
                    
                    }
                    /**
                     * @dev Computes the final balances for a Pool join, which are the current balances plus `amountsIn` minus
                     * accumulated protocol swap fees.
                     */
                    function _computeJoinPoolFinalBalances(
                        bytes32[] memory balances,
                        uint256[] memory maxAmountsIn,
                        uint256[] memory amountsIn,
                        uint256[] memory dueProtocolFeeAmounts
                    ) private view returns (bytes32[] memory finalBalances) {
                        
                        uint256 length = balances.length;
                        finalBalances = new bytes32[](length);
                        for (uint256 i; i < length; ++i) {
                            uint256 amountIn = amountsIn[i];
                            _require(amountIn <= maxAmountsIn[i], Errors.JOIN_ABOVE_MAX);
                            uint256 feeAmount = dueProtocolFeeAmounts[i];
                            // Compute the new Pool balances. Note that the fee amount might be larger than `amountIn`,
                            // resulting in an overall decrease of the Pool's balance for a token.
                            finalBalances[i] = (amountIn >= feeAmount) // This lets us skip checked arithmetic
                                ? balances[i].increaseCash(amountIn - feeAmount)
                                : balances[i].decreaseCash(feeAmount - amountIn);
                        }
                    }
                    /**
                     * @dev Computes the final balances for a Pool exit, which are the current balances minus `amountsOut` and fees
                     * paid (`dueProtocolFeeAmounts`).
                     */
                    function _computeExitPoolFinalBalances(
                        bytes32[] memory balances,
                        uint256[] memory minAmountsOut,
                        uint256[] memory amountsOut,
                        uint256[] memory dueProtocolFeeAmounts
                    ) private view returns (bytes32[] memory finalBalances) {
                        uint256 length = balances.length;
                        finalBalances = new bytes32[](length);
                        for (uint256 i; i < length; ++i) {
                            uint256 amountOut = amountsOut[i];
                            _require(amountOut >= minAmountsOut[i], Errors.EXIT_BELOW_MIN);
                            uint256 feeAmount = dueProtocolFeeAmounts[i];
                            // Compute the new Pool balances. A Pool's token balance always decreases after an exit (potentially by 0).
                            finalBalances[i] = balances[i].decreaseCash(amountOut.add(feeAmount));
                        }
                    }
                    /**
                     * @dev Transfers `amountsIn` from `sender`, checking that they are within their accepted limits, and pays
                     * accumulated protocol swap fees.
                     *
                     * Returns the Pool's final balances, which are the current balances plus `amountsIn` minus accumulated protocol
                     * swap fees.
                     */
                    function _processJoinPoolTransfers(
                        address sender,
                        PoolBalanceChange memory change,
                        bytes32[] memory balances,
                        uint256[] memory amountsIn,
                        uint256[] memory dueProtocolFeeAmounts
                    ) private {
                        // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
                        uint256 wrappedEth;
                        
                        // change.assets.length == balances.length
                        uint256 length = balances.length;
                        for (uint256 i; i < length; ++i) {
                            uint256 amountIn = amountsIn[i];
                            // Receive assets from the sender - possibly from Internal Balance.
                            IAsset asset = change.assets[i];
                            _receiveAsset(asset, amountIn, sender, change.useInternalBalance);
                            if (_isETH(asset)) {
                                wrappedEth = wrappedEth.add(amountIn);
                            }
                            uint256 feeAmount = dueProtocolFeeAmounts[i];
                            _payFeeAmount(_translateToIERC20(asset), feeAmount);
                        }
                        // Handle any used and remaining ETH.
                        _handleRemainingEth(wrappedEth);
                    }
                    /**
                     * @dev Transfers `amountsOut` to `recipient`, checking that they are within their accepted limits, and pays
                     * accumulated protocol swap fees from the Pool.
                     *
                     * Returns the Pool's final balances, which are the current `balances` minus `amountsOut` and fees paid
                     * (`dueProtocolFeeAmounts`).
                     */
                    function _processExitPoolTransfers(
                        address payable recipient,
                        PoolBalanceChange memory change,
                        bytes32[] memory balances,
                        uint256[] memory amountsOut,
                        uint256[] memory dueProtocolFeeAmounts
                    ) private {
                        
                        uint256 length = balances.length;
                        for (uint256 i; i < length; ++i) {
                            uint256 amountOut = amountsOut[i];
                            // Send tokens to the recipient - possibly to Internal Balance
                            IAsset asset = change.assets[i];
                            _sendAsset(asset, amountOut, recipient, change.useInternalBalance);
                            uint256 feeAmount = dueProtocolFeeAmounts[i];
                            _payFeeAmount(_translateToIERC20(asset), feeAmount);
                        }
                    }
                    /**
                     * @dev Returns the total balance for `poolId`'s `expectedTokens`.
                     *
                     * `expectedTokens` must exactly equal the token array returned by `getPoolTokens`: both arrays must have the same
                     * length, elements and order. Additionally, the Pool must have at least one registered token.
                     */
                    function _validateTokensAndGetBalances(bytes32 poolId, IERC20[] memory expectedTokens)
                        private
                        view
                        returns (bytes32[] memory)
                    {
                        (IERC20[] memory actualTokens, bytes32[] memory balances) = _getPoolTokens(poolId);
                        InputHelpers.ensureInputLengthMatch(actualTokens.length, expectedTokens.length);
                        _require(actualTokens.length > 0, Errors.POOL_NO_TOKENS);
                        for (uint256 i; i < actualTokens.length; ++i) {
                            _require(actualTokens[i] == expectedTokens[i], Errors.TOKENS_MISMATCH);
                        }
                        return balances;
                    }
                    /**
                     * @dev Casts an array of uint256 to int256, setting the sign of the result according to the `positive` flag,
                     * without checking whether the values fit in the signed 256 bit range.
                     */
                    function _unsafeCastToInt256(uint256[] memory values, bool positive)
                        private
                        pure
                        returns (int256[] memory signedValues)
                    {
                        signedValues = new int256[](values.length);
                        for (uint256 i; i < values.length; ++i) {
                            signedValues[i] = positive ? int256(values[i]) : -int256(values[i]);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IPoolSwapStructs.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IGeneralPool.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IMinimalSwapInfoPool.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/EnumerableSet.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/EnumerableMap.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeCast.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeERC20.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
                import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
                import "./PoolBalances.sol";
                import "@balancer-labs/v2-vault/contracts/balances/BalanceAllocation.sol";
                /**
                 * Implements the Vault's high-level swap functionality.
                 *
                 * Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. They need not trust the Pool
                 * contracts to do this: all security checks are made by the Vault.
                 *
                 * The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
                 * In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
                 * and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
                 * More complex swaps, such as one 'token in' to multiple tokens out can be achieved by batching together
                 * individual swaps.
                 */
                abstract contract Swaps is ReentrancyGuard, PoolBalances {
                    using SafeERC20 for IERC20;
                    using EnumerableSet for EnumerableSet.AddressSet;
                    using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
                    using Math for int256;
                    using Math for uint256;
                    using SafeCast for uint256;
                    using BalanceAllocation for bytes32;
                    function swap(
                        SingleSwap memory singleSwap,
                        FundManagement memory funds,
                        uint256 limit,
                        uint256 deadline
                    )
                        external
                        payable
                        override
                        nonReentrant
                        whenNotPaused
                        authenticateFor(funds.sender)
                        returns (uint256 amountCalculated)
                    {
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
                        // This revert reason is for consistency with `batchSwap`: an equivalent `swap` performed using that function
                        // would result in this error.
                        _require(singleSwap.amount > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
                        IERC20 tokenIn = _translateToIERC20(singleSwap.assetIn);
                        IERC20 tokenOut = _translateToIERC20(singleSwap.assetOut);
                        _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
                        // Initializing each struct field one-by-one uses less gas than setting all at once.
                        IPoolSwapStructs.SwapRequest memory poolRequest;
                        poolRequest.poolId = singleSwap.poolId;
                        poolRequest.kind = singleSwap.kind;
                        poolRequest.tokenIn = tokenIn;
                        poolRequest.tokenOut = tokenOut;
                        poolRequest.amount = singleSwap.amount;
                        poolRequest.userData = singleSwap.userData;
                        poolRequest.from = funds.sender;
                        poolRequest.to = funds.recipient;
                        // The lastChangeBlock field is left uninitialized.
                        uint256 amountIn;
                        uint256 amountOut;
                        (amountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
                        _require(singleSwap.kind == SwapKind.GIVEN_IN ? amountOut >= limit : amountIn <= limit, Errors.SWAP_LIMIT);
                        _receiveAsset(singleSwap.assetIn, amountIn, funds.sender, funds.fromInternalBalance);
                        _sendAsset(singleSwap.assetOut, amountOut, funds.recipient, funds.toInternalBalance);
                        // If the asset in is ETH, then `amountIn` ETH was wrapped into WETH.
                        _handleRemainingEth(_isETH(singleSwap.assetIn) ? amountIn : 0);
                    }
                    function batchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds,
                        int256[] memory limits,
                        uint256 deadline
                    )
                        external
                        payable
                        override
                        nonReentrant
                        whenNotPaused
                        authenticateFor(funds.sender)
                        returns (int256[] memory assetDeltas)
                    {
                        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                        // solhint-disable-next-line not-rely-on-time
                        _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
                        InputHelpers.ensureInputLengthMatch(assets.length, limits.length);
                        // Perform the swaps, updating the Pool token balances and computing the net Vault asset deltas.
                        assetDeltas = _swapWithPools(swaps, assets, funds, kind);
                        // Process asset deltas, by either transferring assets from the sender (for positive deltas) or to the recipient
                        // (for negative deltas).
                        uint256 wrappedEth = 0;
                        for (uint256 i; i < assets.length; ++i) {
                            IAsset asset = assets[i];
                            int256 delta = assetDeltas[i];
                            _require(delta <= limits[i], Errors.SWAP_LIMIT);
                            if (delta > 0) {
                                uint256 toReceive = uint256(delta);
                                _receiveAsset(asset, toReceive, funds.sender, funds.fromInternalBalance);
                                if (_isETH(asset)) {
                                    wrappedEth = wrappedEth.add(toReceive);
                                }
                            } else if (delta < 0) {
                                uint256 toSend = uint256(-delta);
                                _sendAsset(asset, toSend, funds.recipient, funds.toInternalBalance);
                            }
                        }
                        // Handle any used and remaining ETH.
                        _handleRemainingEth(wrappedEth);
                    }
                    // For `_swapWithPools` to handle both 'given in' and 'given out' swaps, it internally tracks the 'given' amount
                    // (supplied by the caller), and the 'calculated' amount (returned by the Pool in response to the swap request).
                    /**
                     * @dev Given the two swap tokens and the swap kind, returns which one is the 'given' token (the token whose
                     * amount is supplied by the caller).
                     */
                    function _tokenGiven(
                        SwapKind kind,
                        IERC20 tokenIn,
                        IERC20 tokenOut
                    ) private pure returns (IERC20) {
                        return kind == SwapKind.GIVEN_IN ? tokenIn : tokenOut;
                    }
                    /**
                     * @dev Given the two swap tokens and the swap kind, returns which one is the 'calculated' token (the token whose
                     * amount is calculated by the Pool).
                     */
                    function _tokenCalculated(
                        SwapKind kind,
                        IERC20 tokenIn,
                        IERC20 tokenOut
                    ) private pure returns (IERC20) {
                        return kind == SwapKind.GIVEN_IN ? tokenOut : tokenIn;
                    }
                    /**
                     * @dev Returns an ordered pair (amountIn, amountOut) given the 'given' and 'calculated' amounts, and the swap kind.
                     */
                    function _getAmounts(
                        SwapKind kind,
                        uint256 amountGiven,
                        uint256 amountCalculated
                    ) private pure returns (uint256 amountIn, uint256 amountOut) {
                        if (kind == SwapKind.GIVEN_IN) {
                            (amountIn, amountOut) = (amountGiven, amountCalculated);
                        } else {
                            // SwapKind.GIVEN_OUT
                            (amountIn, amountOut) = (amountCalculated, amountGiven);
                        }
                    }
                    /**
                     * @dev Performs all `swaps`, calling swap hooks on the Pool contracts and updating their balances. Does not cause
                     * any transfer of tokens - instead it returns the net Vault token deltas: positive if the Vault should receive
                     * tokens, and negative if it should send them.
                     */
                    function _swapWithPools(
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds,
                        SwapKind kind
                    ) private returns (int256[] memory assetDeltas) {
                        assetDeltas = new int256[](assets.length);
                        // These variables could be declared inside the loop, but that causes the compiler to allocate memory on each
                        // loop iteration, increasing gas costs.
                        BatchSwapStep memory batchSwapStep;
                        IPoolSwapStructs.SwapRequest memory poolRequest;
                        // These store data about the previous swap here to implement multihop logic across swaps.
                        IERC20 previousTokenCalculated;
                        uint256 previousAmountCalculated;
                        for (uint256 i; i < swaps.length; ++i) {
                            batchSwapStep = swaps[i];
                            bool withinBounds = batchSwapStep.assetInIndex < assets.length &&
                                batchSwapStep.assetOutIndex < assets.length;
                            _require(withinBounds, Errors.OUT_OF_BOUNDS);
                            IERC20 tokenIn = _translateToIERC20(assets[batchSwapStep.assetInIndex]);
                            IERC20 tokenOut = _translateToIERC20(assets[batchSwapStep.assetOutIndex]);
                            _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
                            // Sentinel value for multihop logic
                            if (batchSwapStep.amount == 0) {
                                // When the amount given is zero, we use the calculated amount for the previous swap, as long as the
                                // current swap's given token is the previous calculated token. This makes it possible to swap a
                                // given amount of token A for token B, and then use the resulting token B amount to swap for token C.
                                _require(i > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
                                bool usingPreviousToken = previousTokenCalculated == _tokenGiven(kind, tokenIn, tokenOut);
                                _require(usingPreviousToken, Errors.MALCONSTRUCTED_MULTIHOP_SWAP);
                                batchSwapStep.amount = previousAmountCalculated;
                            }
                            // Initializing each struct field one-by-one uses less gas than setting all at once
                            poolRequest.poolId = batchSwapStep.poolId;
                            poolRequest.kind = kind;
                            poolRequest.tokenIn = tokenIn;
                            poolRequest.tokenOut = tokenOut;
                            poolRequest.amount = batchSwapStep.amount;
                            poolRequest.userData = batchSwapStep.userData;
                            poolRequest.from = funds.sender;
                            poolRequest.to = funds.recipient;
                            // The lastChangeBlock field is left uninitialized
                            uint256 amountIn;
                            uint256 amountOut;
                            (previousAmountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
                            previousTokenCalculated = _tokenCalculated(kind, tokenIn, tokenOut);
                            // Accumulate Vault deltas across swaps
                            assetDeltas[batchSwapStep.assetInIndex] = assetDeltas[batchSwapStep.assetInIndex].add(amountIn.toInt256());
                            assetDeltas[batchSwapStep.assetOutIndex] = assetDeltas[batchSwapStep.assetOutIndex].sub(
                                amountOut.toInt256()
                            );
                        }
                    }
                    /**
                     * @dev Performs a swap according to the parameters specified in `request`, calling the Pool's contract hook and
                     * updating the Pool's balance.
                     *
                     * Returns the amount of tokens going into or out of the Vault as a result of this swap, depending on the swap kind.
                     */
                    function _swapWithPool(IPoolSwapStructs.SwapRequest memory request)
                        private
                        returns (
                            uint256 amountCalculated,
                            uint256 amountIn,
                            uint256 amountOut
                        )
                    {
                        // Get the calculated amount from the Pool and update its balances
                        address pool = _getPoolAddress(request.poolId);
                        PoolSpecialization specialization = _getPoolSpecialization(request.poolId);
                        if (specialization == PoolSpecialization.TWO_TOKEN) {
                            amountCalculated = _processTwoTokenPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
                        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                            amountCalculated = _processMinimalSwapInfoPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
                        } else {
                            // PoolSpecialization.GENERAL
                            amountCalculated = _processGeneralPoolSwapRequest(request, IGeneralPool(pool));
                        }
                        (amountIn, amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                        emit Swap(request.poolId, request.tokenIn, request.tokenOut, amountIn, amountOut);
                    }
                    function _processTwoTokenPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IMinimalSwapInfoPool pool)
                        private
                        returns (uint256 amountCalculated)
                    {
                        // For gas efficiency reasons, this function uses low-level knowledge of how Two Token Pool balances are
                        // stored internally, instead of using getters and setters for all operations.
                        (
                            bytes32 tokenABalance,
                            bytes32 tokenBBalance,
                            TwoTokenPoolBalances storage poolBalances
                        ) = _getTwoTokenPoolSharedBalances(request.poolId, request.tokenIn, request.tokenOut);
                        // We have the two Pool balances, but we don't know which one is 'token in' or 'token out'.
                        bytes32 tokenInBalance;
                        bytes32 tokenOutBalance;
                        // In Two Token Pools, token A has a smaller address than token B
                        if (request.tokenIn < request.tokenOut) {
                            // in is A, out is B
                            tokenInBalance = tokenABalance;
                            tokenOutBalance = tokenBBalance;
                        } else {
                            // in is B, out is A
                            tokenOutBalance = tokenABalance;
                            tokenInBalance = tokenBBalance;
                        }
                        // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
                        (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
                            request,
                            pool,
                            tokenInBalance,
                            tokenOutBalance
                        );
                        // We check the token ordering again to create the new shared cash packed struct
                        poolBalances.sharedCash = request.tokenIn < request.tokenOut
                            ? BalanceAllocation.toSharedCash(tokenInBalance, tokenOutBalance) // in is A, out is B
                            : BalanceAllocation.toSharedCash(tokenOutBalance, tokenInBalance); // in is B, out is A
                    }
                    function _processMinimalSwapInfoPoolSwapRequest(
                        IPoolSwapStructs.SwapRequest memory request,
                        IMinimalSwapInfoPool pool
                    ) private returns (uint256 amountCalculated) {
                        bytes32 tokenInBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenIn);
                        bytes32 tokenOutBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenOut);
                        // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
                        (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
                            request,
                            pool,
                            tokenInBalance,
                            tokenOutBalance
                        );
                        _minimalSwapInfoPoolsBalances[request.poolId][request.tokenIn] = tokenInBalance;
                        _minimalSwapInfoPoolsBalances[request.poolId][request.tokenOut] = tokenOutBalance;
                    }
                    /**
                     * @dev Calls the onSwap hook for a Pool that implements IMinimalSwapInfoPool: both Minimal Swap Info and Two Token
                     * Pools do this.
                     */
                    function _callMinimalSwapInfoPoolOnSwapHook(
                        IPoolSwapStructs.SwapRequest memory request,
                        IMinimalSwapInfoPool pool,
                        bytes32 tokenInBalance,
                        bytes32 tokenOutBalance
                    )
                        internal
                        returns (
                            bytes32 newTokenInBalance,
                            bytes32 newTokenOutBalance,
                            uint256 amountCalculated
                        )
                    {
                        uint256 tokenInTotal = tokenInBalance.total();
                        uint256 tokenOutTotal = tokenOutBalance.total();
                        request.lastChangeBlock = Math.max(tokenInBalance.lastChangeBlock(), tokenOutBalance.lastChangeBlock());
                        // Perform the swap request callback, and compute the new balances for 'token in' and 'token out' after the swap
                        amountCalculated = pool.onSwap(request, tokenInTotal, tokenOutTotal);
                        (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                        newTokenInBalance = tokenInBalance.increaseCash(amountIn);
                        newTokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
                    }
                    function _processGeneralPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IGeneralPool pool)
                        private
                        returns (uint256 amountCalculated)
                    {
                        bytes32 tokenInBalance;
                        bytes32 tokenOutBalance;
                        // We access both token indexes without checking existence, because we will do it manually immediately after.
                        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[request.poolId];
                        uint256 indexIn = poolBalances.unchecked_indexOf(request.tokenIn);
                        uint256 indexOut = poolBalances.unchecked_indexOf(request.tokenOut);
                        if (indexIn == 0 || indexOut == 0) {
                            // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
                            // more accurate revert reason.
                            _ensureRegisteredPool(request.poolId);
                            _revert(Errors.TOKEN_NOT_REGISTERED);
                        }
                        // EnumerableMap stores indices *plus one* to use the zero index as a sentinel value - because these are valid,
                        // we can undo this.
                        indexIn -= 1;
                        indexOut -= 1;
                        uint256 tokenAmount = poolBalances.length();
                        uint256[] memory currentBalances = new uint256[](tokenAmount);
                        request.lastChangeBlock = 0;
                        for (uint256 i; i < tokenAmount; ++i) {
                            // Because the iteration is bounded by `tokenAmount`, and no tokens are registered or deregistered here, we
                            // know `i` is a valid token index and can use `unchecked_valueAt` to save storage reads.
                            bytes32 balance = poolBalances.unchecked_valueAt(i);
                            currentBalances[i] = balance.total();
                            request.lastChangeBlock = Math.max(request.lastChangeBlock, balance.lastChangeBlock());
                            if (i == indexIn) {
                                tokenInBalance = balance;
                            } else if (i == indexOut) {
                                tokenOutBalance = balance;
                            }
                        }
                        // Perform the swap request callback and compute the new balances for 'token in' and 'token out' after the swap
                        amountCalculated = pool.onSwap(request, currentBalances, indexIn, indexOut);
                        (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                        tokenInBalance = tokenInBalance.increaseCash(amountIn);
                        tokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
                        // Because no tokens were registered or deregistered between now or when we retrieved the indexes for
                        // 'token in' and 'token out', we can use `unchecked_setAt` to save storage reads.
                        poolBalances.unchecked_setAt(indexIn, tokenInBalance);
                        poolBalances.unchecked_setAt(indexOut, tokenOutBalance);
                    }
                    // This function is not marked as `nonReentrant` because the underlying mechanism relies on reentrancy
                    function queryBatchSwap(
                        SwapKind kind,
                        BatchSwapStep[] memory swaps,
                        IAsset[] memory assets,
                        FundManagement memory funds
                    ) external override returns (int256[] memory) {
                        // In order to accurately 'simulate' swaps, this function actually does perform the swaps, including calling the
                        // Pool hooks and updating balances in storage. However, once it computes the final Vault Deltas, it
                        // reverts unconditionally, returning this array as the revert data.
                        //
                        // By wrapping this reverting call, we can decode the deltas 'returned' and return them as a normal Solidity
                        // function would. The only caveat is the function becomes non-view, but off-chain clients can still call it
                        // via eth_call to get the expected result.
                        //
                        // This technique was inspired by the work from the Gnosis team in the Gnosis Safe contract:
                        // https://github.com/gnosis/safe-contracts/blob/v1.2.0/contracts/GnosisSafe.sol#L265
                        //
                        // Most of this function is implemented using inline assembly, as the actual work it needs to do is not
                        // significant, and Solidity is not particularly well-suited to generate this behavior, resulting in a large
                        // amount of generated bytecode.
                        if (msg.sender != address(this)) {
                            // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
                            // the preceding if statement will be executed instead.
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, ) = address(this).call(msg.data);
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                // This call should always revert to decode the actual asset deltas from the revert reason
                                switch success
                                    case 0 {
                                        // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                                        // stored there as we take full control of the execution and then immediately return.
                                        // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                                        // there was another revert reason and we should forward it.
                                        returndatacopy(0, 0, 0x04)
                                        let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                                        // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                                        if eq(eq(error, 0xfa61cc1200000000000000000000000000000000000000000000000000000000), 0) {
                                            returndatacopy(0, 0, returndatasize())
                                            revert(0, returndatasize())
                                        }
                                        // The returndata contains the signature, followed by the raw memory representation of an array:
                                        // length + data. We need to return an ABI-encoded representation of this array.
                                        // An ABI-encoded array contains an additional field when compared to its raw memory
                                        // representation: an offset to the location of the length. The offset itself is 32 bytes long,
                                        // so the smallest value we  can use is 32 for the data to be located immediately after it.
                                        mstore(0, 32)
                                        // We now copy the raw memory array from returndata into memory. Since the offset takes up 32
                                        // bytes, we start copying at address 0x20. We also get rid of the error signature, which takes
                                        // the first four bytes of returndata.
                                        let size := sub(returndatasize(), 0x04)
                                        returndatacopy(0x20, 0x04, size)
                                        // We finally return the ABI-encoded array, which has a total length equal to that of the array
                                        // (returndata), plus the 32 bytes for the offset.
                                        return(0, add(size, 32))
                                    }
                                    default {
                                        // This call should always revert, but we fail nonetheless if that didn't happen
                                        invalid()
                                    }
                            }
                        } else {
                            int256[] memory deltas = _swapWithPools(swaps, assets, funds, kind);
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                // We will return a raw representation of the array in memory, which is composed of a 32 byte length,
                                // followed by the 32 byte int256 values. Because revert expects a size in bytes, we multiply the array
                                // length (stored at `deltas`) by 32.
                                let size := mul(mload(deltas), 32)
                                // We send one extra value for the error signature "QueryError(int256[])" which is 0xfa61cc12.
                                // We store it in the previous slot to the `deltas` array. We know there will be at least one available
                                // slot due to how the memory scratch space works.
                                // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                                mstore(sub(deltas, 0x20), 0x00000000000000000000000000000000000000000000000000000000fa61cc12)
                                let start := sub(deltas, 0x04)
                                // When copying from `deltas` into returndata, we copy an additional 36 bytes to also return the array's
                                // length and the error signature.
                                revert(start, add(size, 36))
                            }
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-3.0-or-later
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                pragma solidity ^0.7.0;
                pragma experimental ABIEncoderV2;
                import "@balancer-labs/v2-interfaces/contracts/solidity-utils/misc/IWETH.sol";
                import "@balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol";
                import "@balancer-labs/v2-vault/contracts/VaultAuthorization.sol";
                import "@balancer-labs/v2-vault/contracts/FlashLoans.sol";
                import "./Swaps.sol";
                /**
                 * @dev The `Vault` is Balancer V2's core contract. A single instance of it exists for the entire network, and it is the
                 * entity used to interact with Pools by Liquidity Providers who join and exit them, Traders who swap, and Asset
                 * Managers who withdraw and deposit tokens.
                 *
                 * The `Vault`'s source code is split among a number of sub-contracts, with the goal of improving readability and making
                 * understanding the system easier. Most sub-contracts have been marked as `abstract` to explicitly indicate that only
                 * the full `Vault` is meant to be deployed.
                 *
                 * Roughly speaking, these are the contents of each sub-contract:
                 *
                 *  - `AssetManagers`: Pool token Asset Manager registry, and Asset Manager interactions.
                 *  - `Fees`: set and compute protocol fees.
                 *  - `FlashLoans`: flash loan transfers and fees.
                 *  - `PoolBalances`: Pool joins and exits.
                 *  - `PoolRegistry`: Pool registration, ID management, and basic queries.
                 *  - `PoolTokens`: Pool token registration and registration, and balance queries.
                 *  - `Swaps`: Pool swaps.
                 *  - `UserBalance`: manage user balances (Internal Balance operations and external balance transfers)
                 *  - `VaultAuthorization`: access control, relayers and signature validation.
                 *
                 * Additionally, the different Pool specializations are handled by the `GeneralPoolsBalance`,
                 * `MinimalSwapInfoPoolsBalance` and `TwoTokenPoolsBalance` sub-contracts, which in turn make use of the
                 * `BalanceAllocation` library.
                 *
                 * The most important goal of the `Vault` is to make token swaps use as little gas as possible. This is reflected in a
                 * multitude of design decisions, from minor things like the format used to store Pool IDs, to major features such as
                 * the different Pool specialization settings.
                 *
                 * Finally, the large number of tasks carried out by the Vault means its bytecode is very large, close to exceeding
                 * the contract size limit imposed by EIP 170 (https://eips.ethereum.org/EIPS/eip-170). Manual tuning of the source code
                 * was required to improve code generation and bring the bytecode size below this limit. This includes extensive
                 * utilization of `internal` functions (particularly inside modifiers), usage of named return arguments, dedicated
                 * storage access methods, dynamic revert reason generation, and usage of inline assembly, to name a few.
                 */
                contract Vault is VaultAuthorization, FlashLoans, Swaps {
                    constructor(
                        IAuthorizer authorizer,
                        IWETH weth,
                        uint256 pauseWindowDuration,
                        uint256 bufferPeriodDuration
                    ) VaultAuthorization(authorizer) AssetHelpers(weth) TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration) {
                        // solhint-disable-previous-line no-empty-blocks
                    }
                    function setPaused(bool paused) external override nonReentrant authenticate {
                        _setPaused(paused);
                    }
                    // solhint-disable-next-line func-name-mixedcase
                    function WETH() external view override returns (IWETH) {
                        return _WETH();
                    }
                }
                

                File 4 of 7: WETH9
                // Copyright (C) 2015, 2016, 2017 Dapphub
                
                // This program is free software: you can redistribute it and/or modify
                // it under the terms of the GNU General Public License as published by
                // the Free Software Foundation, either version 3 of the License, or
                // (at your option) any later version.
                
                // This program is distributed in the hope that it will be useful,
                // but WITHOUT ANY WARRANTY; without even the implied warranty of
                // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                // GNU General Public License for more details.
                
                // You should have received a copy of the GNU General Public License
                // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                
                pragma solidity ^0.4.18;
                
                contract WETH9 {
                    string public name     = "Wrapped Ether";
                    string public symbol   = "WETH";
                    uint8  public decimals = 18;
                
                    event  Approval(address indexed src, address indexed guy, uint wad);
                    event  Transfer(address indexed src, address indexed dst, uint wad);
                    event  Deposit(address indexed dst, uint wad);
                    event  Withdrawal(address indexed src, uint wad);
                
                    mapping (address => uint)                       public  balanceOf;
                    mapping (address => mapping (address => uint))  public  allowance;
                
                    function() public payable {
                        deposit();
                    }
                    function deposit() public payable {
                        balanceOf[msg.sender] += msg.value;
                        Deposit(msg.sender, msg.value);
                    }
                    function withdraw(uint wad) public {
                        require(balanceOf[msg.sender] >= wad);
                        balanceOf[msg.sender] -= wad;
                        msg.sender.transfer(wad);
                        Withdrawal(msg.sender, wad);
                    }
                
                    function totalSupply() public view returns (uint) {
                        return this.balance;
                    }
                
                    function approve(address guy, uint wad) public returns (bool) {
                        allowance[msg.sender][guy] = wad;
                        Approval(msg.sender, guy, wad);
                        return true;
                    }
                
                    function transfer(address dst, uint wad) public returns (bool) {
                        return transferFrom(msg.sender, dst, wad);
                    }
                
                    function transferFrom(address src, address dst, uint wad)
                        public
                        returns (bool)
                    {
                        require(balanceOf[src] >= wad);
                
                        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
                            require(allowance[src][msg.sender] >= wad);
                            allowance[src][msg.sender] -= wad;
                        }
                
                        balanceOf[src] -= wad;
                        balanceOf[dst] += wad;
                
                        Transfer(src, dst, wad);
                
                        return true;
                    }
                }
                
                
                /*
                                    GNU GENERAL PUBLIC LICENSE
                                       Version 3, 29 June 2007
                
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                File 5 of 7: V2DutchOrderReactor
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {BaseReactor} from "./BaseReactor.sol";
                import {IPermit2} from "permit2/src/interfaces/IPermit2.sol";
                import {Permit2Lib} from "../lib/Permit2Lib.sol";
                import {ExclusivityLib} from "../lib/ExclusivityLib.sol";
                import {DutchDecayLib} from "../lib/DutchDecayLib.sol";
                import {V2DutchOrderLib, V2DutchOrder, CosignerData, DutchOutput, DutchInput} from "../lib/V2DutchOrderLib.sol";
                import {SignedOrder, ResolvedOrder} from "../base/ReactorStructs.sol";
                /// @notice Reactor for v2 dutch orders
                /// @dev V2 orders must be cosigned by the specified cosigner to override timings and starting values
                /// @dev resolution behavior:
                /// - If cosignature is invalid or not from specified cosigner, revert
                /// - If inputAmount is 0, then use baseInput
                /// - If inputAmount is nonzero, then ensure it is less than specified baseInput and replace startAmount
                /// - For each outputAmount:
                ///   - If amount is 0, then use baseOutput
                ///   - If amount is nonzero, then ensure it is greater than specified baseOutput and replace startAmount
                contract V2DutchOrderReactor is BaseReactor {
                    using Permit2Lib for ResolvedOrder;
                    using V2DutchOrderLib for V2DutchOrder;
                    using DutchDecayLib for DutchOutput[];
                    using DutchDecayLib for DutchInput;
                    using ExclusivityLib for ResolvedOrder;
                    /// @notice thrown when an order's deadline is before its end time
                    error DeadlineBeforeEndTime();
                    /// @notice thrown when an order's cosignature does not match the expected cosigner
                    error InvalidCosignature();
                    /// @notice thrown when an order's cosigner input is greater than the specified
                    error InvalidCosignerInput();
                    /// @notice thrown when an order's cosigner output is less than the specified
                    error InvalidCosignerOutput();
                    constructor(IPermit2 _permit2, address _protocolFeeOwner) BaseReactor(_permit2, _protocolFeeOwner) {}
                    /// @inheritdoc BaseReactor
                    function _resolve(SignedOrder calldata signedOrder)
                        internal
                        view
                        virtual
                        override
                        returns (ResolvedOrder memory resolvedOrder)
                    {
                        V2DutchOrder memory order = abi.decode(signedOrder.order, (V2DutchOrder));
                        // hash the order _before_ overriding amounts, as this is the hash the user would have signed
                        bytes32 orderHash = order.hash();
                        _validateOrder(orderHash, order);
                        _updateWithCosignerAmounts(order);
                        resolvedOrder = ResolvedOrder({
                            info: order.info,
                            input: order.baseInput.decay(order.cosignerData.decayStartTime, order.cosignerData.decayEndTime),
                            outputs: order.baseOutputs.decay(order.cosignerData.decayStartTime, order.cosignerData.decayEndTime),
                            sig: signedOrder.sig,
                            hash: orderHash
                        });
                        resolvedOrder.handleExclusiveOverride(
                            order.cosignerData.exclusiveFiller,
                            order.cosignerData.decayStartTime,
                            order.cosignerData.exclusivityOverrideBps
                        );
                    }
                    /// @inheritdoc BaseReactor
                    function _transferInputTokens(ResolvedOrder memory order, address to) internal override {
                        permit2.permitWitnessTransferFrom(
                            order.toPermit(),
                            order.transferDetails(to),
                            order.info.swapper,
                            order.hash,
                            V2DutchOrderLib.PERMIT2_ORDER_TYPE,
                            order.sig
                        );
                    }
                    function _updateWithCosignerAmounts(V2DutchOrder memory order) internal pure {
                        if (order.cosignerData.inputAmount != 0) {
                            if (order.cosignerData.inputAmount > order.baseInput.startAmount) {
                                revert InvalidCosignerInput();
                            }
                            order.baseInput.startAmount = order.cosignerData.inputAmount;
                        }
                        if (order.cosignerData.outputAmounts.length != order.baseOutputs.length) {
                            revert InvalidCosignerOutput();
                        }
                        for (uint256 i = 0; i < order.baseOutputs.length; i++) {
                            DutchOutput memory output = order.baseOutputs[i];
                            uint256 outputAmount = order.cosignerData.outputAmounts[i];
                            if (outputAmount != 0) {
                                if (outputAmount < output.startAmount) {
                                    revert InvalidCosignerOutput();
                                }
                                output.startAmount = outputAmount;
                            }
                        }
                    }
                    /// @notice validate the dutch order fields
                    /// - deadline must be greater than or equal to decayEndTime
                    /// - decayEndTime must be greater than decayStartTime
                    /// - if there's input decay, outputs must not decay
                    /// @dev Throws if the order is invalid
                    function _validateOrder(bytes32 orderHash, V2DutchOrder memory order) internal pure {
                        if (order.info.deadline < order.cosignerData.decayEndTime) {
                            revert DeadlineBeforeEndTime();
                        }
                        (bytes32 r, bytes32 s) = abi.decode(order.cosignature, (bytes32, bytes32));
                        uint8 v = uint8(order.cosignature[64]);
                        // cosigner signs over (orderHash || cosignerData)
                        address signer = ecrecover(keccak256(abi.encodePacked(orderHash, abi.encode(order.cosignerData))), v, r, s);
                        if (order.cosigner != signer || signer == address(0)) {
                            revert InvalidCosignature();
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {SafeTransferLib} from "solmate/src/utils/SafeTransferLib.sol";
                import {ReentrancyGuard} from "openzeppelin-contracts/security/ReentrancyGuard.sol";
                import {IPermit2} from "permit2/src/interfaces/IPermit2.sol";
                import {ERC20} from "solmate/src/tokens/ERC20.sol";
                import {ReactorEvents} from "../base/ReactorEvents.sol";
                import {ResolvedOrderLib} from "../lib/ResolvedOrderLib.sol";
                import {CurrencyLibrary} from "../lib/CurrencyLibrary.sol";
                import {IReactorCallback} from "../interfaces/IReactorCallback.sol";
                import {IReactor} from "../interfaces/IReactor.sol";
                import {ProtocolFees} from "../base/ProtocolFees.sol";
                import {SignedOrder, ResolvedOrder, OutputToken} from "../base/ReactorStructs.sol";
                /// @notice Generic reactor logic for settling off-chain signed orders
                ///     using arbitrary fill methods specified by a filler
                abstract contract BaseReactor is IReactor, ReactorEvents, ProtocolFees, ReentrancyGuard {
                    using SafeTransferLib for ERC20;
                    using ResolvedOrderLib for ResolvedOrder;
                    using CurrencyLibrary for address;
                    /// @notice permit2 address used for token transfers and signature verification
                    IPermit2 public immutable permit2;
                    constructor(IPermit2 _permit2, address _protocolFeeOwner) ProtocolFees(_protocolFeeOwner) {
                        permit2 = _permit2;
                    }
                    /// @inheritdoc IReactor
                    function execute(SignedOrder calldata order) external payable override nonReentrant {
                        ResolvedOrder[] memory resolvedOrders = new ResolvedOrder[](1);
                        resolvedOrders[0] = _resolve(order);
                        _prepare(resolvedOrders);
                        _fill(resolvedOrders);
                    }
                    /// @inheritdoc IReactor
                    function executeWithCallback(SignedOrder calldata order, bytes calldata callbackData)
                        external
                        payable
                        override
                        nonReentrant
                    {
                        ResolvedOrder[] memory resolvedOrders = new ResolvedOrder[](1);
                        resolvedOrders[0] = _resolve(order);
                        _prepare(resolvedOrders);
                        IReactorCallback(msg.sender).reactorCallback(resolvedOrders, callbackData);
                        _fill(resolvedOrders);
                    }
                    /// @inheritdoc IReactor
                    function executeBatch(SignedOrder[] calldata orders) external payable override nonReentrant {
                        uint256 ordersLength = orders.length;
                        ResolvedOrder[] memory resolvedOrders = new ResolvedOrder[](ordersLength);
                        unchecked {
                            for (uint256 i = 0; i < ordersLength; i++) {
                                resolvedOrders[i] = _resolve(orders[i]);
                            }
                        }
                        _prepare(resolvedOrders);
                        _fill(resolvedOrders);
                    }
                    /// @inheritdoc IReactor
                    function executeBatchWithCallback(SignedOrder[] calldata orders, bytes calldata callbackData)
                        external
                        payable
                        override
                        nonReentrant
                    {
                        uint256 ordersLength = orders.length;
                        ResolvedOrder[] memory resolvedOrders = new ResolvedOrder[](ordersLength);
                        unchecked {
                            for (uint256 i = 0; i < ordersLength; i++) {
                                resolvedOrders[i] = _resolve(orders[i]);
                            }
                        }
                        _prepare(resolvedOrders);
                        IReactorCallback(msg.sender).reactorCallback(resolvedOrders, callbackData);
                        _fill(resolvedOrders);
                    }
                    /// @notice validates, injects fees, and transfers input tokens in preparation for order fill
                    /// @param orders The orders to prepare
                    function _prepare(ResolvedOrder[] memory orders) internal {
                        uint256 ordersLength = orders.length;
                        unchecked {
                            for (uint256 i = 0; i < ordersLength; i++) {
                                ResolvedOrder memory order = orders[i];
                                _injectFees(order);
                                order.validate(msg.sender);
                                _transferInputTokens(order, msg.sender);
                            }
                        }
                    }
                    /// @notice fills a list of orders, ensuring all outputs are satisfied
                    /// @param orders The orders to fill
                    function _fill(ResolvedOrder[] memory orders) internal {
                        uint256 ordersLength = orders.length;
                        // attempt to transfer all currencies to all recipients
                        unchecked {
                            // transfer output tokens to their respective recipients
                            for (uint256 i = 0; i < ordersLength; i++) {
                                ResolvedOrder memory resolvedOrder = orders[i];
                                uint256 outputsLength = resolvedOrder.outputs.length;
                                for (uint256 j = 0; j < outputsLength; j++) {
                                    OutputToken memory output = resolvedOrder.outputs[j];
                                    output.token.transferFill(output.recipient, output.amount);
                                }
                                emit Fill(orders[i].hash, msg.sender, resolvedOrder.info.swapper, resolvedOrder.info.nonce);
                            }
                        }
                        // refund any remaining ETH to the filler. Only occurs when filler sends more ETH than required to
                        // `execute()` or `executeBatch()`, or when there is excess contract balance remaining from others
                        // incorrectly calling execute/executeBatch without direct filler method but with a msg.value
                        if (address(this).balance > 0) {
                            CurrencyLibrary.transferNative(msg.sender, address(this).balance);
                        }
                    }
                    receive() external payable {
                        // receive native asset to support native output
                    }
                    /// @notice Resolve order-type specific requirements into a generic order with the final inputs and outputs.
                    /// @param order The encoded order to resolve
                    /// @return resolvedOrder generic resolved order of inputs and outputs
                    /// @dev should revert on any order-type-specific validation errors
                    function _resolve(SignedOrder calldata order) internal view virtual returns (ResolvedOrder memory resolvedOrder);
                    /// @notice Transfers tokens to the fillContract
                    /// @param order The encoded order to transfer tokens for
                    /// @param to The address to transfer tokens to
                    function _transferInputTokens(ResolvedOrder memory order, address to) internal virtual;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.0;
                import {ISignatureTransfer} from "./ISignatureTransfer.sol";
                import {IAllowanceTransfer} from "./IAllowanceTransfer.sol";
                /// @notice Permit2 handles signature-based transfers in SignatureTransfer and allowance-based transfers in AllowanceTransfer.
                /// @dev Users must approve Permit2 before calling any of the transfer functions.
                interface IPermit2 is ISignatureTransfer, IAllowanceTransfer {
                // IPermit2 unifies the two interfaces so users have maximal flexibility with their approval.
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ISignatureTransfer} from "permit2/src/interfaces/ISignatureTransfer.sol";
                import {ResolvedOrder} from "../base/ReactorStructs.sol";
                /// @notice handling some permit2-specific encoding
                library Permit2Lib {
                    /// @notice returns a ResolvedOrder into a permit object
                    function toPermit(ResolvedOrder memory order)
                        internal
                        pure
                        returns (ISignatureTransfer.PermitTransferFrom memory)
                    {
                        return ISignatureTransfer.PermitTransferFrom({
                            permitted: ISignatureTransfer.TokenPermissions({
                                token: address(order.input.token),
                                amount: order.input.maxAmount
                            }),
                            nonce: order.info.nonce,
                            deadline: order.info.deadline
                        });
                    }
                    /// @notice returns a ResolvedOrder into a permit object
                    function transferDetails(ResolvedOrder memory order, address to)
                        internal
                        pure
                        returns (ISignatureTransfer.SignatureTransferDetails memory)
                    {
                        return ISignatureTransfer.SignatureTransferDetails({to: to, requestedAmount: order.input.amount});
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {FixedPointMathLib} from "solmate/src/utils/FixedPointMathLib.sol";
                import {ResolvedOrder, OutputToken} from "../base/ReactorStructs.sol";
                /// @title ExclusiveOverride
                /// @dev This library handles order exclusivity
                ///  giving the configured filler exclusive rights to fill the order before exclusivityEndTime
                ///  or enforcing an override price improvement by non-exclusive fillers
                library ExclusivityLib {
                    using FixedPointMathLib for uint256;
                    /// @notice thrown when an order has strict exclusivity and the filler does not have it
                    error NoExclusiveOverride();
                    uint256 private constant STRICT_EXCLUSIVITY = 0;
                    uint256 private constant BPS = 10_000;
                    /// @notice Applies exclusivity override to the resolved order if necessary
                    /// @param order The order to apply exclusivity override to
                    /// @param exclusive The exclusive address
                    /// @param exclusivityEndTime The exclusivity end time
                    /// @param exclusivityOverrideBps The exclusivity override BPS
                    function handleExclusiveOverride(
                        ResolvedOrder memory order,
                        address exclusive,
                        uint256 exclusivityEndTime,
                        uint256 exclusivityOverrideBps
                    ) internal view {
                        // if the filler has fill right, we proceed with the order as-is
                        if (hasFillingRights(exclusive, exclusivityEndTime)) {
                            return;
                        }
                        // if override is 0, then assume strict exclusivity so the order cannot be filled
                        if (exclusivityOverrideBps == STRICT_EXCLUSIVITY) {
                            revert NoExclusiveOverride();
                        }
                        // scale outputs by override amount
                        OutputToken[] memory outputs = order.outputs;
                        for (uint256 i = 0; i < outputs.length;) {
                            OutputToken memory output = outputs[i];
                            output.amount = output.amount.mulDivUp(BPS + exclusivityOverrideBps, BPS);
                            unchecked {
                                i++;
                            }
                        }
                    }
                    /// @notice checks if the caller currently has filling rights on the order
                    /// @dev if the order has no exclusivity, always returns true
                    /// @dev if the order has active exclusivity and the current filler is the exclusive address, returns true
                    /// @dev if the order has active exclusivity and the current filler is not the exclusive address, returns false
                    function hasFillingRights(address exclusive, uint256 exclusivityEndTime) internal view returns (bool) {
                        return exclusive == address(0) || block.timestamp > exclusivityEndTime || exclusive == msg.sender;
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {OutputToken, InputToken} from "../base/ReactorStructs.sol";
                import {DutchOutput, DutchInput} from "../lib/DutchOrderLib.sol";
                import {FixedPointMathLib} from "solmate/src/utils/FixedPointMathLib.sol";
                /// @notice helpers for handling dutch order objects
                library DutchDecayLib {
                    using FixedPointMathLib for uint256;
                    /// @notice thrown if the decay direction is incorrect
                    /// - for DutchInput, startAmount must be less than or equal to endAmount
                    /// - for DutchOutput, startAmount must be greater than or equal to endAmount
                    error IncorrectAmounts();
                    /// @notice thrown if the endTime of an order is before startTime
                    error EndTimeBeforeStartTime();
                    /// @notice calculates an amount using linear decay over time from decayStartTime to decayEndTime
                    /// @dev handles both positive and negative decay depending on startAmount and endAmount
                    /// @param startAmount The amount of tokens at decayStartTime
                    /// @param endAmount The amount of tokens at decayEndTime
                    /// @param decayStartTime The time to start decaying linearly
                    /// @param decayEndTime The time to stop decaying linearly
                    function decay(uint256 startAmount, uint256 endAmount, uint256 decayStartTime, uint256 decayEndTime)
                        internal
                        view
                        returns (uint256 decayedAmount)
                    {
                        if (startAmount == endAmount) {
                            return startAmount;
                        } else if (decayEndTime <= decayStartTime) {
                            revert EndTimeBeforeStartTime();
                        } else if (decayEndTime <= block.timestamp) {
                            decayedAmount = endAmount;
                        } else if (decayStartTime >= block.timestamp) {
                            decayedAmount = startAmount;
                        } else {
                            unchecked {
                                uint256 elapsed = block.timestamp - decayStartTime;
                                uint256 duration = decayEndTime - decayStartTime;
                                if (endAmount < startAmount) {
                                    decayedAmount = startAmount - (startAmount - endAmount).mulDivDown(elapsed, duration);
                                } else {
                                    decayedAmount = startAmount + (endAmount - startAmount).mulDivUp(elapsed, duration);
                                }
                            }
                        }
                    }
                    /// @notice returns a decayed output using the given dutch spec and times
                    /// @param output The output to decay
                    /// @param decayStartTime The time to start decaying
                    /// @param decayEndTime The time to end decaying
                    /// @return result a decayed output
                    function decay(DutchOutput memory output, uint256 decayStartTime, uint256 decayEndTime)
                        internal
                        view
                        returns (OutputToken memory result)
                    {
                        if (output.startAmount < output.endAmount) {
                            revert IncorrectAmounts();
                        }
                        uint256 decayedOutput = DutchDecayLib.decay(output.startAmount, output.endAmount, decayStartTime, decayEndTime);
                        result = OutputToken(output.token, decayedOutput, output.recipient);
                    }
                    /// @notice returns a decayed output array using the given dutch spec and times
                    /// @param outputs The output array to decay
                    /// @param decayStartTime The time to start decaying
                    /// @param decayEndTime The time to end decaying
                    /// @return result a decayed output array
                    function decay(DutchOutput[] memory outputs, uint256 decayStartTime, uint256 decayEndTime)
                        internal
                        view
                        returns (OutputToken[] memory result)
                    {
                        uint256 outputLength = outputs.length;
                        result = new OutputToken[](outputLength);
                        unchecked {
                            for (uint256 i = 0; i < outputLength; i++) {
                                result[i] = decay(outputs[i], decayStartTime, decayEndTime);
                            }
                        }
                    }
                    /// @notice returns a decayed input using the given dutch spec and times
                    /// @param input The input to decay
                    /// @param decayStartTime The time to start decaying
                    /// @param decayEndTime The time to end decaying
                    /// @return result a decayed input
                    function decay(DutchInput memory input, uint256 decayStartTime, uint256 decayEndTime)
                        internal
                        view
                        returns (InputToken memory result)
                    {
                        if (input.startAmount > input.endAmount) {
                            revert IncorrectAmounts();
                        }
                        uint256 decayedInput = DutchDecayLib.decay(input.startAmount, input.endAmount, decayStartTime, decayEndTime);
                        result = InputToken(input.token, decayedInput, input.endAmount);
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {OrderInfo} from "../base/ReactorStructs.sol";
                import {DutchOutput, DutchInput, DutchOrderLib} from "./DutchOrderLib.sol";
                import {OrderInfoLib} from "./OrderInfoLib.sol";
                struct CosignerData {
                    // The time at which the DutchOutputs start decaying
                    uint256 decayStartTime;
                    // The time at which price becomes static
                    uint256 decayEndTime;
                    // The address who has exclusive rights to the order until decayStartTime
                    address exclusiveFiller;
                    // The amount in bps that a non-exclusive filler needs to improve the outputs by to be able to fill the order
                    uint256 exclusivityOverrideBps;
                    // The tokens that the swapper will provide when settling the order
                    uint256 inputAmount;
                    // The tokens that must be received to satisfy the order
                    uint256[] outputAmounts;
                }
                struct V2DutchOrder {
                    // generic order information
                    OrderInfo info;
                    // The address which must cosign the full order
                    address cosigner;
                    // The tokens that the swapper will provide when settling the order
                    DutchInput baseInput;
                    // The tokens that must be received to satisfy the order
                    DutchOutput[] baseOutputs;
                    // signed over by the cosigner
                    CosignerData cosignerData;
                    // signature from the cosigner over (orderHash || cosignerData)
                    bytes cosignature;
                }
                /// @notice helpers for handling v2 dutch order objects
                library V2DutchOrderLib {
                    using DutchOrderLib for DutchOutput[];
                    using OrderInfoLib for OrderInfo;
                    bytes internal constant V2_DUTCH_ORDER_TYPE = abi.encodePacked(
                        "V2DutchOrder(",
                        "OrderInfo info,",
                        "address cosigner,",
                        "address baseInputToken,",
                        "uint256 baseInputStartAmount,",
                        "uint256 baseInputEndAmount,",
                        "DutchOutput[] baseOutputs)"
                    );
                    bytes internal constant ORDER_TYPE =
                        abi.encodePacked(V2_DUTCH_ORDER_TYPE, DutchOrderLib.DUTCH_OUTPUT_TYPE, OrderInfoLib.ORDER_INFO_TYPE);
                    bytes32 internal constant ORDER_TYPE_HASH = keccak256(ORDER_TYPE);
                    /// @dev Note that sub-structs have to be defined in alphabetical order in the EIP-712 spec
                    string internal constant PERMIT2_ORDER_TYPE = string(
                        abi.encodePacked(
                            "V2DutchOrder witness)",
                            DutchOrderLib.DUTCH_OUTPUT_TYPE,
                            OrderInfoLib.ORDER_INFO_TYPE,
                            DutchOrderLib.TOKEN_PERMISSIONS_TYPE,
                            V2_DUTCH_ORDER_TYPE
                        )
                    );
                    /// @notice hash the given order
                    /// @param order the order to hash
                    /// @return the eip-712 order hash
                    function hash(V2DutchOrder memory order) internal pure returns (bytes32) {
                        return keccak256(
                            abi.encode(
                                ORDER_TYPE_HASH,
                                order.info.hash(),
                                order.cosigner,
                                order.baseInput.token,
                                order.baseInput.startAmount,
                                order.baseInput.endAmount,
                                order.baseOutputs.hash()
                            )
                        );
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {IReactor} from "../interfaces/IReactor.sol";
                import {IValidationCallback} from "../interfaces/IValidationCallback.sol";
                import {ERC20} from "solmate/src/tokens/ERC20.sol";
                /// @dev generic order information
                ///  should be included as the first field in any concrete order types
                struct OrderInfo {
                    // The address of the reactor that this order is targeting
                    // Note that this must be included in every order so the swapper
                    // signature commits to the specific reactor that they trust to fill their order properly
                    IReactor reactor;
                    // The address of the user which created the order
                    // Note that this must be included so that order hashes are unique by swapper
                    address swapper;
                    // The nonce of the order, allowing for signature replay protection and cancellation
                    uint256 nonce;
                    // The timestamp after which this order is no longer valid
                    uint256 deadline;
                    // Custom validation contract
                    IValidationCallback additionalValidationContract;
                    // Encoded validation params for additionalValidationContract
                    bytes additionalValidationData;
                }
                /// @dev tokens that need to be sent from the swapper in order to satisfy an order
                struct InputToken {
                    ERC20 token;
                    uint256 amount;
                    // Needed for dutch decaying inputs
                    uint256 maxAmount;
                }
                /// @dev tokens that need to be received by the recipient in order to satisfy an order
                struct OutputToken {
                    address token;
                    uint256 amount;
                    address recipient;
                }
                /// @dev generic concrete order that specifies exact tokens which need to be sent and received
                struct ResolvedOrder {
                    OrderInfo info;
                    InputToken input;
                    OutputToken[] outputs;
                    bytes sig;
                    bytes32 hash;
                }
                /// @dev external struct including a generic encoded order and swapper signature
                ///  The order bytes will be parsed and mapped to a ResolvedOrder in the concrete reactor contract
                struct SignedOrder {
                    bytes order;
                    bytes sig;
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                import {ERC20} from "../tokens/ERC20.sol";
                /// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
                /// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
                /// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
                library SafeTransferLib {
                    /*//////////////////////////////////////////////////////////////
                                             ETH OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferETH(address to, uint256 amount) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Transfer the ETH and store if it succeeded or not.
                            success := call(gas(), to, amount, 0, 0, 0, 0)
                        }
                        require(success, "ETH_TRANSFER_FAILED");
                    }
                    /*//////////////////////////////////////////////////////////////
                                            ERC20 OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferFrom(
                        ERC20 token,
                        address from,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "from" argument.
                            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FROM_FAILED");
                    }
                    function safeTransfer(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FAILED");
                    }
                    function safeApprove(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "APPROVE_FAILED");
                    }
                }
                // SPDX-License-Identifier: MIT
                // OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
                pragma solidity ^0.8.0;
                /**
                 * @dev Contract module that helps prevent reentrant calls to a function.
                 *
                 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
                 * available, which can be applied to functions to make sure there are no nested
                 * (reentrant) calls to them.
                 *
                 * Note that because there is a single `nonReentrant` guard, functions marked as
                 * `nonReentrant` may not call one another. This can be worked around by making
                 * those functions `private`, and then adding `external` `nonReentrant` entry
                 * points to them.
                 *
                 * TIP: If you would like to learn more about reentrancy and alternative ways
                 * to protect against it, check out our blog post
                 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
                 */
                abstract contract ReentrancyGuard {
                    // Booleans are more expensive than uint256 or any type that takes up a full
                    // word because each write operation emits an extra SLOAD to first read the
                    // slot's contents, replace the bits taken up by the boolean, and then write
                    // back. This is the compiler's defense against contract upgrades and
                    // pointer aliasing, and it cannot be disabled.
                    // The values being non-zero value makes deployment a bit more expensive,
                    // but in exchange the refund on every call to nonReentrant will be lower in
                    // amount. Since refunds are capped to a percentage of the total
                    // transaction's gas, it is best to keep them low in cases like this one, to
                    // increase the likelihood of the full refund coming into effect.
                    uint256 private constant _NOT_ENTERED = 1;
                    uint256 private constant _ENTERED = 2;
                    uint256 private _status;
                    constructor() {
                        _status = _NOT_ENTERED;
                    }
                    /**
                     * @dev Prevents a contract from calling itself, directly or indirectly.
                     * Calling a `nonReentrant` function from another `nonReentrant`
                     * function is not supported. It is possible to prevent this from happening
                     * by making the `nonReentrant` function external, and making it call a
                     * `private` function that does the actual work.
                     */
                    modifier nonReentrant() {
                        _nonReentrantBefore();
                        _;
                        _nonReentrantAfter();
                    }
                    function _nonReentrantBefore() private {
                        // On the first call to nonReentrant, _status will be _NOT_ENTERED
                        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                        // Any calls to nonReentrant after this point will fail
                        _status = _ENTERED;
                    }
                    function _nonReentrantAfter() private {
                        // By storing the original value once again, a refund is triggered (see
                        // https://eips.ethereum.org/EIPS/eip-2200)
                        _status = _NOT_ENTERED;
                    }
                    /**
                     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
                     * `nonReentrant` function in the call stack.
                     */
                    function _reentrancyGuardEntered() internal view returns (bool) {
                        return _status == _ENTERED;
                    }
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
                /// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
                /// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
                abstract contract ERC20 {
                    /*//////////////////////////////////////////////////////////////
                                                 EVENTS
                    //////////////////////////////////////////////////////////////*/
                    event Transfer(address indexed from, address indexed to, uint256 amount);
                    event Approval(address indexed owner, address indexed spender, uint256 amount);
                    /*//////////////////////////////////////////////////////////////
                                            METADATA STORAGE
                    //////////////////////////////////////////////////////////////*/
                    string public name;
                    string public symbol;
                    uint8 public immutable decimals;
                    /*//////////////////////////////////////////////////////////////
                                              ERC20 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 public totalSupply;
                    mapping(address => uint256) public balanceOf;
                    mapping(address => mapping(address => uint256)) public allowance;
                    /*//////////////////////////////////////////////////////////////
                                            EIP-2612 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 internal immutable INITIAL_CHAIN_ID;
                    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
                    mapping(address => uint256) public nonces;
                    /*//////////////////////////////////////////////////////////////
                                               CONSTRUCTOR
                    //////////////////////////////////////////////////////////////*/
                    constructor(
                        string memory _name,
                        string memory _symbol,
                        uint8 _decimals
                    ) {
                        name = _name;
                        symbol = _symbol;
                        decimals = _decimals;
                        INITIAL_CHAIN_ID = block.chainid;
                        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
                    }
                    /*//////////////////////////////////////////////////////////////
                                               ERC20 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function approve(address spender, uint256 amount) public virtual returns (bool) {
                        allowance[msg.sender][spender] = amount;
                        emit Approval(msg.sender, spender, amount);
                        return true;
                    }
                    function transfer(address to, uint256 amount) public virtual returns (bool) {
                        balanceOf[msg.sender] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(msg.sender, to, amount);
                        return true;
                    }
                    function transferFrom(
                        address from,
                        address to,
                        uint256 amount
                    ) public virtual returns (bool) {
                        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
                        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
                        balanceOf[from] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(from, to, amount);
                        return true;
                    }
                    /*//////////////////////////////////////////////////////////////
                                             EIP-2612 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function permit(
                        address owner,
                        address spender,
                        uint256 value,
                        uint256 deadline,
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) public virtual {
                        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
                        // Unchecked because the only math done is incrementing
                        // the owner's nonce which cannot realistically overflow.
                        unchecked {
                            address recoveredAddress = ecrecover(
                                keccak256(
                                    abi.encodePacked(
                                        "\\x19\\x01",
                                        DOMAIN_SEPARATOR(),
                                        keccak256(
                                            abi.encode(
                                                keccak256(
                                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                                ),
                                                owner,
                                                spender,
                                                value,
                                                nonces[owner]++,
                                                deadline
                                            )
                                        )
                                    )
                                ),
                                v,
                                r,
                                s
                            );
                            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
                            allowance[recoveredAddress][spender] = value;
                        }
                        emit Approval(owner, spender, value);
                    }
                    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
                        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
                    }
                    function computeDomainSeparator() internal view virtual returns (bytes32) {
                        return
                            keccak256(
                                abi.encode(
                                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                                    keccak256(bytes(name)),
                                    keccak256("1"),
                                    block.chainid,
                                    address(this)
                                )
                            );
                    }
                    /*//////////////////////////////////////////////////////////////
                                        INTERNAL MINT/BURN LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function _mint(address to, uint256 amount) internal virtual {
                        totalSupply += amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(address(0), to, amount);
                    }
                    function _burn(address from, uint256 amount) internal virtual {
                        balanceOf[from] -= amount;
                        // Cannot underflow because a user's balance
                        // will never be larger than the total supply.
                        unchecked {
                            totalSupply -= amount;
                        }
                        emit Transfer(from, address(0), amount);
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                /// @notice standardized events that should be emitted by all reactors
                /// @dev collated into one library to help with forge expectEmit integration
                /// @dev and for reactors which dont use base
                interface ReactorEvents {
                    /// @notice emitted when an order is filled
                    /// @param orderHash The hash of the order that was filled
                    /// @param filler The address which executed the fill
                    /// @param swapper The swapper of the filled order
                    /// @param nonce The nonce of the filled order
                    event Fill(bytes32 indexed orderHash, address indexed filler, address indexed swapper, uint256 nonce);
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ResolvedOrder} from "../base/ReactorStructs.sol";
                /// @notice Library for handling validation of resolved orders
                library ResolvedOrderLib {
                    /// @notice thrown when the order targets a different reactor
                    error InvalidReactor();
                    /// @notice Validates a resolved order, reverting if invalid
                    /// @param filler The filler of the order
                    function validate(ResolvedOrder memory resolvedOrder, address filler) internal view {
                        if (address(this) != address(resolvedOrder.info.reactor)) {
                            revert InvalidReactor();
                        }
                        if (address(resolvedOrder.info.additionalValidationContract) != address(0)) {
                            resolvedOrder.info.additionalValidationContract.validate(filler, resolvedOrder);
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ERC20} from "solmate/src/tokens/ERC20.sol";
                import {IPermit2} from "permit2/src/interfaces/IPermit2.sol";
                import {SafeCast} from "openzeppelin-contracts/utils/math/SafeCast.sol";
                import {SafeTransferLib} from "solmate/src/utils/SafeTransferLib.sol";
                address constant NATIVE = 0x0000000000000000000000000000000000000000;
                /// @title CurrencyLibrary
                /// @dev This library allows for transferring native ETH and ERC20s via direct filler OR fill contract.
                library CurrencyLibrary {
                    using SafeTransferLib for ERC20;
                    /// @notice Thrown when a native transfer fails
                    error NativeTransferFailed();
                    /// @notice Get the balance of a currency for addr
                    /// @param currency The currency to get the balance of
                    /// @param addr The address to get the balance of
                    /// @return balance The balance of the currency for addr
                    function balanceOf(address currency, address addr) internal view returns (uint256 balance) {
                        if (isNative(currency)) {
                            balance = addr.balance;
                        } else {
                            balance = ERC20(currency).balanceOf(addr);
                        }
                    }
                    /// @notice Transfer currency from the caller to recipient
                    /// @dev for native outputs we will already have the currency in local balance
                    /// @param currency The currency to transfer
                    /// @param recipient The recipient of the currency
                    /// @param amount The amount of currency to transfer
                    function transferFill(address currency, address recipient, uint256 amount) internal {
                        if (isNative(currency)) {
                            // we will have received native assets directly so can directly transfer
                            transferNative(recipient, amount);
                        } else {
                            // else the caller must have approved the token for the fill
                            ERC20(currency).safeTransferFrom(msg.sender, recipient, amount);
                        }
                    }
                    /// @notice Transfer native currency to recipient
                    /// @param recipient The recipient of the currency
                    /// @param amount The amount of currency to transfer
                    function transferNative(address recipient, uint256 amount) internal {
                        (bool success,) = recipient.call{value: amount}("");
                        if (!success) revert NativeTransferFailed();
                    }
                    /// @notice returns true if currency is native
                    /// @param currency The currency to check
                    /// @return true if currency is native
                    function isNative(address currency) internal pure returns (bool) {
                        return currency == NATIVE;
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ResolvedOrder} from "../base/ReactorStructs.sol";
                /// @notice Callback for executing orders through a reactor.
                interface IReactorCallback {
                    /// @notice Called by the reactor during the execution of an order
                    /// @param resolvedOrders Has inputs and outputs
                    /// @param callbackData The callbackData specified for an order execution
                    /// @dev Must have approved each token and amount in outputs to the msg.sender
                    function reactorCallback(ResolvedOrder[] memory resolvedOrders, bytes memory callbackData) external;
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {SignedOrder} from "../base/ReactorStructs.sol";
                /// @notice Interface for order execution reactors
                interface IReactor {
                    /// @notice Execute a single order
                    /// @param order The order definition and valid signature to execute
                    function execute(SignedOrder calldata order) external payable;
                    /// @notice Execute a single order using the given callback data
                    /// @param order The order definition and valid signature to execute
                    /// @param callbackData The callbackData to pass to the callback
                    function executeWithCallback(SignedOrder calldata order, bytes calldata callbackData) external payable;
                    /// @notice Execute the given orders at once
                    /// @param orders The order definitions and valid signatures to execute
                    function executeBatch(SignedOrder[] calldata orders) external payable;
                    /// @notice Execute the given orders at once using a callback with the given callback data
                    /// @param orders The order definitions and valid signatures to execute
                    /// @param callbackData The callbackData to pass to the callback
                    function executeBatchWithCallback(SignedOrder[] calldata orders, bytes calldata callbackData) external payable;
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {Owned} from "solmate/src/auth/Owned.sol";
                import {SafeTransferLib} from "solmate/src/utils/SafeTransferLib.sol";
                import {FixedPointMathLib} from "solmate/src/utils/FixedPointMathLib.sol";
                import {ERC20} from "solmate/src/tokens/ERC20.sol";
                import {IProtocolFeeController} from "../interfaces/IProtocolFeeController.sol";
                import {CurrencyLibrary} from "../lib/CurrencyLibrary.sol";
                import {ResolvedOrder, OutputToken} from "../base/ReactorStructs.sol";
                /// @notice Handling for protocol fees
                abstract contract ProtocolFees is Owned {
                    using SafeTransferLib for ERC20;
                    using FixedPointMathLib for uint256;
                    using CurrencyLibrary for address;
                    /// @notice thrown if two fee outputs have the same token
                    error DuplicateFeeOutput(address duplicateToken);
                    /// @notice thrown if a given fee output is greater than MAX_FEE_BPS of the order outputs
                    error FeeTooLarge(address token, uint256 amount, address recipient);
                    /// @notice thrown if a fee output token does not have a corresponding non-fee output
                    error InvalidFeeToken(address feeToken);
                    /// @notice thrown if fees are taken on both inputs and outputs
                    error InputAndOutputFees();
                    event ProtocolFeeControllerSet(address oldFeeController, address newFeeController);
                    uint256 private constant BPS = 10_000;
                    uint256 private constant MAX_FEE_BPS = 5;
                    /// @dev The address of the fee controller
                    IProtocolFeeController public feeController;
                    // @notice Required to customize owner from constructor of BaseReactor.sol
                    constructor(address _owner) Owned(_owner) {}
                    /// @notice Injects fees into an order
                    /// @dev modifies the orders to include protocol fee outputs
                    /// @param order The encoded order to inject fees into
                    function _injectFees(ResolvedOrder memory order) internal view {
                        if (address(feeController) == address(0)) {
                            return;
                        }
                        OutputToken[] memory feeOutputs = feeController.getFeeOutputs(order);
                        uint256 outputsLength = order.outputs.length;
                        uint256 feeOutputsLength = feeOutputs.length;
                        // apply fee outputs
                        // fill new outputs with old outputs
                        OutputToken[] memory newOutputs = new OutputToken[](outputsLength + feeOutputsLength);
                        for (uint256 i = 0; i < outputsLength; i++) {
                            newOutputs[i] = order.outputs[i];
                        }
                        bool outputFeeTaken = false;
                        bool inputFeeTaken = false;
                        for (uint256 i = 0; i < feeOutputsLength; i++) {
                            OutputToken memory feeOutput = feeOutputs[i];
                            // assert no duplicates
                            for (uint256 j = 0; j < i; j++) {
                                if (feeOutput.token == feeOutputs[j].token) {
                                    revert DuplicateFeeOutput(feeOutput.token);
                                }
                            }
                            // assert not greater than MAX_FEE_BPS
                            uint256 tokenValue;
                            for (uint256 j = 0; j < outputsLength; j++) {
                                OutputToken memory output = order.outputs[j];
                                if (output.token == feeOutput.token) {
                                    if (inputFeeTaken) revert InputAndOutputFees();
                                    tokenValue += output.amount;
                                    outputFeeTaken = true;
                                }
                            }
                            // allow fee on input token as well
                            if (address(order.input.token) == feeOutput.token) {
                                if (outputFeeTaken) revert InputAndOutputFees();
                                tokenValue += order.input.amount;
                                inputFeeTaken = true;
                            }
                            if (tokenValue == 0) revert InvalidFeeToken(feeOutput.token);
                            if (feeOutput.amount > tokenValue.mulDivDown(MAX_FEE_BPS, BPS)) {
                                revert FeeTooLarge(feeOutput.token, feeOutput.amount, feeOutput.recipient);
                            }
                            unchecked {
                                newOutputs[outputsLength + i] = feeOutput;
                            }
                        }
                        order.outputs = newOutputs;
                    }
                    /// @notice sets the protocol fee controller
                    /// @dev only callable by the owner
                    /// @param _newFeeController the new fee controller
                    function setProtocolFeeController(address _newFeeController) external onlyOwner {
                        address oldFeeController = address(feeController);
                        feeController = IProtocolFeeController(_newFeeController);
                        emit ProtocolFeeControllerSet(oldFeeController, _newFeeController);
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                import {IEIP712} from "./IEIP712.sol";
                /// @title SignatureTransfer
                /// @notice Handles ERC20 token transfers through signature based actions
                /// @dev Requires user's token approval on the Permit2 contract
                interface ISignatureTransfer is IEIP712 {
                    /// @notice Thrown when the requested amount for a transfer is larger than the permissioned amount
                    /// @param maxAmount The maximum amount a spender can request to transfer
                    error InvalidAmount(uint256 maxAmount);
                    /// @notice Thrown when the number of tokens permissioned to a spender does not match the number of tokens being transferred
                    /// @dev If the spender does not need to transfer the number of tokens permitted, the spender can request amount 0 to be transferred
                    error LengthMismatch();
                    /// @notice Emits an event when the owner successfully invalidates an unordered nonce.
                    event UnorderedNonceInvalidation(address indexed owner, uint256 word, uint256 mask);
                    /// @notice The token and amount details for a transfer signed in the permit transfer signature
                    struct TokenPermissions {
                        // ERC20 token address
                        address token;
                        // the maximum amount that can be spent
                        uint256 amount;
                    }
                    /// @notice The signed permit message for a single token transfer
                    struct PermitTransferFrom {
                        TokenPermissions permitted;
                        // a unique value for every token owner's signature to prevent signature replays
                        uint256 nonce;
                        // deadline on the permit signature
                        uint256 deadline;
                    }
                    /// @notice Specifies the recipient address and amount for batched transfers.
                    /// @dev Recipients and amounts correspond to the index of the signed token permissions array.
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount.
                    struct SignatureTransferDetails {
                        // recipient address
                        address to;
                        // spender requested amount
                        uint256 requestedAmount;
                    }
                    /// @notice Used to reconstruct the signed permit message for multiple token transfers
                    /// @dev Do not need to pass in spender address as it is required that it is msg.sender
                    /// @dev Note that a user still signs over a spender address
                    struct PermitBatchTransferFrom {
                        // the tokens and corresponding amounts permitted for a transfer
                        TokenPermissions[] permitted;
                        // a unique value for every token owner's signature to prevent signature replays
                        uint256 nonce;
                        // deadline on the permit signature
                        uint256 deadline;
                    }
                    /// @notice A map from token owner address and a caller specified word index to a bitmap. Used to set bits in the bitmap to prevent against signature replay protection
                    /// @dev Uses unordered nonces so that permit messages do not need to be spent in a certain order
                    /// @dev The mapping is indexed first by the token owner, then by an index specified in the nonce
                    /// @dev It returns a uint256 bitmap
                    /// @dev The index, or wordPosition is capped at type(uint248).max
                    function nonceBitmap(address, uint256) external view returns (uint256);
                    /// @notice Transfers a token using a signed permit message
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails The spender's requested transfer details for the permitted token
                    /// @param signature The signature to verify
                    function permitTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers a token using a signed permit message
                    /// @notice Includes extra data provided by the caller to verify signature over
                    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails The spender's requested transfer details for the permitted token
                    /// @param witness Extra data to include when checking the user signature
                    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
                    /// @param signature The signature to verify
                    function permitWitnessTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers multiple tokens using a signed permit message
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
                    /// @param signature The signature to verify
                    function permitTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers multiple tokens using a signed permit message
                    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
                    /// @notice Includes extra data provided by the caller to verify signature over
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
                    /// @param witness Extra data to include when checking the user signature
                    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
                    /// @param signature The signature to verify
                    function permitWitnessTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external;
                    /// @notice Invalidates the bits specified in mask for the bitmap at the word position
                    /// @dev The wordPos is maxed at type(uint248).max
                    /// @param wordPos A number to index the nonceBitmap at
                    /// @param mask A bitmap masked against msg.sender's current bitmap at the word position
                    function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                import {IEIP712} from "./IEIP712.sol";
                /// @title AllowanceTransfer
                /// @notice Handles ERC20 token permissions through signature based allowance setting and ERC20 token transfers by checking allowed amounts
                /// @dev Requires user's token approval on the Permit2 contract
                interface IAllowanceTransfer is IEIP712 {
                    /// @notice Thrown when an allowance on a token has expired.
                    /// @param deadline The timestamp at which the allowed amount is no longer valid
                    error AllowanceExpired(uint256 deadline);
                    /// @notice Thrown when an allowance on a token has been depleted.
                    /// @param amount The maximum amount allowed
                    error InsufficientAllowance(uint256 amount);
                    /// @notice Thrown when too many nonces are invalidated.
                    error ExcessiveInvalidation();
                    /// @notice Emits an event when the owner successfully invalidates an ordered nonce.
                    event NonceInvalidation(
                        address indexed owner, address indexed token, address indexed spender, uint48 newNonce, uint48 oldNonce
                    );
                    /// @notice Emits an event when the owner successfully sets permissions on a token for the spender.
                    event Approval(
                        address indexed owner, address indexed token, address indexed spender, uint160 amount, uint48 expiration
                    );
                    /// @notice Emits an event when the owner successfully sets permissions using a permit signature on a token for the spender.
                    event Permit(
                        address indexed owner,
                        address indexed token,
                        address indexed spender,
                        uint160 amount,
                        uint48 expiration,
                        uint48 nonce
                    );
                    /// @notice Emits an event when the owner sets the allowance back to 0 with the lockdown function.
                    event Lockdown(address indexed owner, address token, address spender);
                    /// @notice The permit data for a token
                    struct PermitDetails {
                        // ERC20 token address
                        address token;
                        // the maximum amount allowed to spend
                        uint160 amount;
                        // timestamp at which a spender's token allowances become invalid
                        uint48 expiration;
                        // an incrementing value indexed per owner,token,and spender for each signature
                        uint48 nonce;
                    }
                    /// @notice The permit message signed for a single token allownce
                    struct PermitSingle {
                        // the permit data for a single token alownce
                        PermitDetails details;
                        // address permissioned on the allowed tokens
                        address spender;
                        // deadline on the permit signature
                        uint256 sigDeadline;
                    }
                    /// @notice The permit message signed for multiple token allowances
                    struct PermitBatch {
                        // the permit data for multiple token allowances
                        PermitDetails[] details;
                        // address permissioned on the allowed tokens
                        address spender;
                        // deadline on the permit signature
                        uint256 sigDeadline;
                    }
                    /// @notice The saved permissions
                    /// @dev This info is saved per owner, per token, per spender and all signed over in the permit message
                    /// @dev Setting amount to type(uint160).max sets an unlimited approval
                    struct PackedAllowance {
                        // amount allowed
                        uint160 amount;
                        // permission expiry
                        uint48 expiration;
                        // an incrementing value indexed per owner,token,and spender for each signature
                        uint48 nonce;
                    }
                    /// @notice A token spender pair.
                    struct TokenSpenderPair {
                        // the token the spender is approved
                        address token;
                        // the spender address
                        address spender;
                    }
                    /// @notice Details for a token transfer.
                    struct AllowanceTransferDetails {
                        // the owner of the token
                        address from;
                        // the recipient of the token
                        address to;
                        // the amount of the token
                        uint160 amount;
                        // the token to be transferred
                        address token;
                    }
                    /// @notice A mapping from owner address to token address to spender address to PackedAllowance struct, which contains details and conditions of the approval.
                    /// @notice The mapping is indexed in the above order see: allowance[ownerAddress][tokenAddress][spenderAddress]
                    /// @dev The packed slot holds the allowed amount, expiration at which the allowed amount is no longer valid, and current nonce thats updated on any signature based approvals.
                    function allowance(address user, address token, address spender)
                        external
                        view
                        returns (uint160 amount, uint48 expiration, uint48 nonce);
                    /// @notice Approves the spender to use up to amount of the specified token up until the expiration
                    /// @param token The token to approve
                    /// @param spender The spender address to approve
                    /// @param amount The approved amount of the token
                    /// @param expiration The timestamp at which the approval is no longer valid
                    /// @dev The packed allowance also holds a nonce, which will stay unchanged in approve
                    /// @dev Setting amount to type(uint160).max sets an unlimited approval
                    function approve(address token, address spender, uint160 amount, uint48 expiration) external;
                    /// @notice Permit a spender to a given amount of the owners token via the owner's EIP-712 signature
                    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
                    /// @param owner The owner of the tokens being approved
                    /// @param permitSingle Data signed over by the owner specifying the terms of approval
                    /// @param signature The owner's signature over the permit data
                    function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external;
                    /// @notice Permit a spender to the signed amounts of the owners tokens via the owner's EIP-712 signature
                    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
                    /// @param owner The owner of the tokens being approved
                    /// @param permitBatch Data signed over by the owner specifying the terms of approval
                    /// @param signature The owner's signature over the permit data
                    function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external;
                    /// @notice Transfer approved tokens from one address to another
                    /// @param from The address to transfer from
                    /// @param to The address of the recipient
                    /// @param amount The amount of the token to transfer
                    /// @param token The token address to transfer
                    /// @dev Requires the from address to have approved at least the desired amount
                    /// of tokens to msg.sender.
                    function transferFrom(address from, address to, uint160 amount, address token) external;
                    /// @notice Transfer approved tokens in a batch
                    /// @param transferDetails Array of owners, recipients, amounts, and tokens for the transfers
                    /// @dev Requires the from addresses to have approved at least the desired amount
                    /// of tokens to msg.sender.
                    function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external;
                    /// @notice Enables performing a "lockdown" of the sender's Permit2 identity
                    /// by batch revoking approvals
                    /// @param approvals Array of approvals to revoke.
                    function lockdown(TokenSpenderPair[] calldata approvals) external;
                    /// @notice Invalidate nonces for a given (token, spender) pair
                    /// @param token The token to invalidate nonces for
                    /// @param spender The spender to invalidate nonces for
                    /// @param newNonce The new nonce to set. Invalidates all nonces less than it.
                    /// @dev Can't invalidate more than 2**16 nonces per transaction.
                    function invalidateNonces(address token, address spender, uint48 newNonce) external;
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Arithmetic library with operations for fixed-point numbers.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/FixedPointMathLib.sol)
                /// @author Inspired by USM (https://github.com/usmfum/USM/blob/master/contracts/WadMath.sol)
                library FixedPointMathLib {
                    /*//////////////////////////////////////////////////////////////
                                    SIMPLIFIED FIXED POINT OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    uint256 internal constant MAX_UINT256 = 2**256 - 1;
                    uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.
                    function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                        return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
                    }
                    function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                        return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
                    }
                    function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                        return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
                    }
                    function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                        return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
                    }
                    /*//////////////////////////////////////////////////////////////
                                    LOW LEVEL FIXED POINT OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function mulDivDown(
                        uint256 x,
                        uint256 y,
                        uint256 denominator
                    ) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
                            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                                revert(0, 0)
                            }
                            // Divide x * y by the denominator.
                            z := div(mul(x, y), denominator)
                        }
                    }
                    function mulDivUp(
                        uint256 x,
                        uint256 y,
                        uint256 denominator
                    ) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
                            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                                revert(0, 0)
                            }
                            // If x * y modulo the denominator is strictly greater than 0,
                            // 1 is added to round up the division of x * y by the denominator.
                            z := add(gt(mod(mul(x, y), denominator), 0), div(mul(x, y), denominator))
                        }
                    }
                    function rpow(
                        uint256 x,
                        uint256 n,
                        uint256 scalar
                    ) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            switch x
                            case 0 {
                                switch n
                                case 0 {
                                    // 0 ** 0 = 1
                                    z := scalar
                                }
                                default {
                                    // 0 ** n = 0
                                    z := 0
                                }
                            }
                            default {
                                switch mod(n, 2)
                                case 0 {
                                    // If n is even, store scalar in z for now.
                                    z := scalar
                                }
                                default {
                                    // If n is odd, store x in z for now.
                                    z := x
                                }
                                // Shifting right by 1 is like dividing by 2.
                                let half := shr(1, scalar)
                                for {
                                    // Shift n right by 1 before looping to halve it.
                                    n := shr(1, n)
                                } n {
                                    // Shift n right by 1 each iteration to halve it.
                                    n := shr(1, n)
                                } {
                                    // Revert immediately if x ** 2 would overflow.
                                    // Equivalent to iszero(eq(div(xx, x), x)) here.
                                    if shr(128, x) {
                                        revert(0, 0)
                                    }
                                    // Store x squared.
                                    let xx := mul(x, x)
                                    // Round to the nearest number.
                                    let xxRound := add(xx, half)
                                    // Revert if xx + half overflowed.
                                    if lt(xxRound, xx) {
                                        revert(0, 0)
                                    }
                                    // Set x to scaled xxRound.
                                    x := div(xxRound, scalar)
                                    // If n is even:
                                    if mod(n, 2) {
                                        // Compute z * x.
                                        let zx := mul(z, x)
                                        // If z * x overflowed:
                                        if iszero(eq(div(zx, x), z)) {
                                            // Revert if x is non-zero.
                                            if iszero(iszero(x)) {
                                                revert(0, 0)
                                            }
                                        }
                                        // Round to the nearest number.
                                        let zxRound := add(zx, half)
                                        // Revert if zx + half overflowed.
                                        if lt(zxRound, zx) {
                                            revert(0, 0)
                                        }
                                        // Return properly scaled zxRound.
                                        z := div(zxRound, scalar)
                                    }
                                }
                            }
                        }
                    }
                    /*//////////////////////////////////////////////////////////////
                                        GENERAL NUMBER UTILITIES
                    //////////////////////////////////////////////////////////////*/
                    function sqrt(uint256 x) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            let y := x // We start y at x, which will help us make our initial estimate.
                            z := 181 // The "correct" value is 1, but this saves a multiplication later.
                            // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
                            // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.
                            // We check y >= 2^(k + 8) but shift right by k bits
                            // each branch to ensure that if x >= 256, then y >= 256.
                            if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                                y := shr(128, y)
                                z := shl(64, z)
                            }
                            if iszero(lt(y, 0x1000000000000000000)) {
                                y := shr(64, y)
                                z := shl(32, z)
                            }
                            if iszero(lt(y, 0x10000000000)) {
                                y := shr(32, y)
                                z := shl(16, z)
                            }
                            if iszero(lt(y, 0x1000000)) {
                                y := shr(16, y)
                                z := shl(8, z)
                            }
                            // Goal was to get z*z*y within a small factor of x. More iterations could
                            // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
                            // We ensured y >= 256 so that the relative difference between y and y+1 is small.
                            // That's not possible if x < 256 but we can just verify those cases exhaustively.
                            // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
                            // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
                            // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.
                            // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
                            // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.
                            // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
                            // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.
                            // There is no overflow risk here since y < 2^136 after the first branch above.
                            z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.
                            // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            z := shr(1, add(z, div(x, z)))
                            // If x+1 is a perfect square, the Babylonian method cycles between
                            // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
                            // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
                            // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
                            // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
                            z := sub(z, lt(div(x, z), z))
                        }
                    }
                    function unsafeMod(uint256 x, uint256 y) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Mod x by y. Note this will return
                            // 0 instead of reverting if y is zero.
                            z := mod(x, y)
                        }
                    }
                    function unsafeDiv(uint256 x, uint256 y) internal pure returns (uint256 r) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Divide x by y. Note this will return
                            // 0 instead of reverting if y is zero.
                            r := div(x, y)
                        }
                    }
                    function unsafeDivUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Add 1 to x * y if x % y > 0. Note this will
                            // return 0 instead of reverting if y is zero.
                            z := add(gt(mod(x, y), 0), div(x, y))
                        }
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {OrderInfo} from "../base/ReactorStructs.sol";
                import {OrderInfoLib} from "./OrderInfoLib.sol";
                import {ERC20} from "solmate/src/tokens/ERC20.sol";
                /// @dev An amount of output tokens that decreases linearly over time
                struct DutchOutput {
                    // The ERC20 token address (or native ETH address)
                    address token;
                    // The amount of tokens at the start of the time period
                    uint256 startAmount;
                    // The amount of tokens at the end of the time period
                    uint256 endAmount;
                    // The address who must receive the tokens to satisfy the order
                    address recipient;
                }
                /// @dev An amount of input tokens that increases linearly over time
                struct DutchInput {
                    // The ERC20 token address
                    ERC20 token;
                    // The amount of tokens at the start of the time period
                    uint256 startAmount;
                    // The amount of tokens at the end of the time period
                    uint256 endAmount;
                }
                struct DutchOrder {
                    // generic order information
                    OrderInfo info;
                    // The time at which the DutchOutputs start decaying
                    uint256 decayStartTime;
                    // The time at which price becomes static
                    uint256 decayEndTime;
                    // The tokens that the swapper will provide when settling the order
                    DutchInput input;
                    // The tokens that must be received to satisfy the order
                    DutchOutput[] outputs;
                }
                /// @notice helpers for handling dutch order objects
                library DutchOrderLib {
                    using OrderInfoLib for OrderInfo;
                    bytes internal constant DUTCH_OUTPUT_TYPE =
                        "DutchOutput(address token,uint256 startAmount,uint256 endAmount,address recipient)";
                    bytes32 internal constant DUTCH_OUTPUT_TYPE_HASH = keccak256(DUTCH_OUTPUT_TYPE);
                    bytes internal constant DUTCH_LIMIT_ORDER_TYPE = abi.encodePacked(
                        "DutchOrder(",
                        "OrderInfo info,",
                        "uint256 decayStartTime,",
                        "uint256 decayEndTime,",
                        "address inputToken,",
                        "uint256 inputStartAmount,",
                        "uint256 inputEndAmount,",
                        "DutchOutput[] outputs)"
                    );
                    /// @dev Note that sub-structs have to be defined in alphabetical order in the EIP-712 spec
                    bytes internal constant ORDER_TYPE =
                        abi.encodePacked(DUTCH_LIMIT_ORDER_TYPE, DUTCH_OUTPUT_TYPE, OrderInfoLib.ORDER_INFO_TYPE);
                    bytes32 internal constant ORDER_TYPE_HASH = keccak256(ORDER_TYPE);
                    string internal constant TOKEN_PERMISSIONS_TYPE = "TokenPermissions(address token,uint256 amount)";
                    string internal constant PERMIT2_ORDER_TYPE =
                        string(abi.encodePacked("DutchOrder witness)", ORDER_TYPE, TOKEN_PERMISSIONS_TYPE));
                    /// @notice hash the given output
                    /// @param output the output to hash
                    /// @return the eip-712 output hash
                    function hash(DutchOutput memory output) internal pure returns (bytes32) {
                        return keccak256(
                            abi.encode(DUTCH_OUTPUT_TYPE_HASH, output.token, output.startAmount, output.endAmount, output.recipient)
                        );
                    }
                    /// @notice hash the given outputs
                    /// @param outputs the outputs to hash
                    /// @return the eip-712 outputs hash
                    function hash(DutchOutput[] memory outputs) internal pure returns (bytes32) {
                        unchecked {
                            bytes memory packedHashes = new bytes(32 * outputs.length);
                            for (uint256 i = 0; i < outputs.length; i++) {
                                bytes32 outputHash = hash(outputs[i]);
                                assembly {
                                    mstore(add(add(packedHashes, 0x20), mul(i, 0x20)), outputHash)
                                }
                            }
                            return keccak256(packedHashes);
                        }
                    }
                    /// @notice hash the given order
                    /// @param order the order to hash
                    /// @return the eip-712 order hash
                    function hash(DutchOrder memory order) internal pure returns (bytes32) {
                        return keccak256(
                            abi.encode(
                                ORDER_TYPE_HASH,
                                order.info.hash(),
                                order.decayStartTime,
                                order.decayEndTime,
                                order.input.token,
                                order.input.startAmount,
                                order.input.endAmount,
                                hash(order.outputs)
                            )
                        );
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {OrderInfo} from "../base/ReactorStructs.sol";
                /// @notice helpers for handling OrderInfo objects
                library OrderInfoLib {
                    bytes internal constant ORDER_INFO_TYPE =
                        "OrderInfo(address reactor,address swapper,uint256 nonce,uint256 deadline,address additionalValidationContract,bytes additionalValidationData)";
                    bytes32 internal constant ORDER_INFO_TYPE_HASH = keccak256(ORDER_INFO_TYPE);
                    /// @notice hash an OrderInfo object
                    /// @param info The OrderInfo object to hash
                    function hash(OrderInfo memory info) internal pure returns (bytes32) {
                        return keccak256(
                            abi.encode(
                                ORDER_INFO_TYPE_HASH,
                                info.reactor,
                                info.swapper,
                                info.nonce,
                                info.deadline,
                                info.additionalValidationContract,
                                keccak256(info.additionalValidationData)
                            )
                        );
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ResolvedOrder} from "../base/ReactorStructs.sol";
                /// @notice Callback to validate an order
                interface IValidationCallback {
                    /// @notice Called by the reactor for custom validation of an order. Will revert if validation fails
                    /// @param filler The filler of the order
                    /// @param resolvedOrder The resolved order to fill
                    function validate(address filler, ResolvedOrder calldata resolvedOrder) external view;
                }
                // SPDX-License-Identifier: MIT
                // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SafeCast.sol)
                // This file was procedurally generated from scripts/generate/templates/SafeCast.js.
                pragma solidity ^0.8.0;
                /**
                 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
                 * checks.
                 *
                 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
                 * easily result in undesired exploitation or bugs, since developers usually
                 * assume that overflows raise errors. `SafeCast` restores this intuition by
                 * reverting the transaction when such an operation overflows.
                 *
                 * Using this library instead of the unchecked operations eliminates an entire
                 * class of bugs, so it's recommended to use it always.
                 *
                 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
                 * all math on `uint256` and `int256` and then downcasting.
                 */
                library SafeCast {
                    /**
                     * @dev Returns the downcasted uint248 from uint256, reverting on
                     * overflow (when the input is greater than largest uint248).
                     *
                     * Counterpart to Solidity's `uint248` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 248 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint248(uint256 value) internal pure returns (uint248) {
                        require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
                        return uint248(value);
                    }
                    /**
                     * @dev Returns the downcasted uint240 from uint256, reverting on
                     * overflow (when the input is greater than largest uint240).
                     *
                     * Counterpart to Solidity's `uint240` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 240 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint240(uint256 value) internal pure returns (uint240) {
                        require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
                        return uint240(value);
                    }
                    /**
                     * @dev Returns the downcasted uint232 from uint256, reverting on
                     * overflow (when the input is greater than largest uint232).
                     *
                     * Counterpart to Solidity's `uint232` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 232 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint232(uint256 value) internal pure returns (uint232) {
                        require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
                        return uint232(value);
                    }
                    /**
                     * @dev Returns the downcasted uint224 from uint256, reverting on
                     * overflow (when the input is greater than largest uint224).
                     *
                     * Counterpart to Solidity's `uint224` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 224 bits
                     *
                     * _Available since v4.2._
                     */
                    function toUint224(uint256 value) internal pure returns (uint224) {
                        require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
                        return uint224(value);
                    }
                    /**
                     * @dev Returns the downcasted uint216 from uint256, reverting on
                     * overflow (when the input is greater than largest uint216).
                     *
                     * Counterpart to Solidity's `uint216` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 216 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint216(uint256 value) internal pure returns (uint216) {
                        require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
                        return uint216(value);
                    }
                    /**
                     * @dev Returns the downcasted uint208 from uint256, reverting on
                     * overflow (when the input is greater than largest uint208).
                     *
                     * Counterpart to Solidity's `uint208` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 208 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint208(uint256 value) internal pure returns (uint208) {
                        require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
                        return uint208(value);
                    }
                    /**
                     * @dev Returns the downcasted uint200 from uint256, reverting on
                     * overflow (when the input is greater than largest uint200).
                     *
                     * Counterpart to Solidity's `uint200` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 200 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint200(uint256 value) internal pure returns (uint200) {
                        require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
                        return uint200(value);
                    }
                    /**
                     * @dev Returns the downcasted uint192 from uint256, reverting on
                     * overflow (when the input is greater than largest uint192).
                     *
                     * Counterpart to Solidity's `uint192` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 192 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint192(uint256 value) internal pure returns (uint192) {
                        require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
                        return uint192(value);
                    }
                    /**
                     * @dev Returns the downcasted uint184 from uint256, reverting on
                     * overflow (when the input is greater than largest uint184).
                     *
                     * Counterpart to Solidity's `uint184` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 184 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint184(uint256 value) internal pure returns (uint184) {
                        require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
                        return uint184(value);
                    }
                    /**
                     * @dev Returns the downcasted uint176 from uint256, reverting on
                     * overflow (when the input is greater than largest uint176).
                     *
                     * Counterpart to Solidity's `uint176` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 176 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint176(uint256 value) internal pure returns (uint176) {
                        require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
                        return uint176(value);
                    }
                    /**
                     * @dev Returns the downcasted uint168 from uint256, reverting on
                     * overflow (when the input is greater than largest uint168).
                     *
                     * Counterpart to Solidity's `uint168` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 168 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint168(uint256 value) internal pure returns (uint168) {
                        require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
                        return uint168(value);
                    }
                    /**
                     * @dev Returns the downcasted uint160 from uint256, reverting on
                     * overflow (when the input is greater than largest uint160).
                     *
                     * Counterpart to Solidity's `uint160` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 160 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint160(uint256 value) internal pure returns (uint160) {
                        require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
                        return uint160(value);
                    }
                    /**
                     * @dev Returns the downcasted uint152 from uint256, reverting on
                     * overflow (when the input is greater than largest uint152).
                     *
                     * Counterpart to Solidity's `uint152` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 152 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint152(uint256 value) internal pure returns (uint152) {
                        require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
                        return uint152(value);
                    }
                    /**
                     * @dev Returns the downcasted uint144 from uint256, reverting on
                     * overflow (when the input is greater than largest uint144).
                     *
                     * Counterpart to Solidity's `uint144` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 144 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint144(uint256 value) internal pure returns (uint144) {
                        require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
                        return uint144(value);
                    }
                    /**
                     * @dev Returns the downcasted uint136 from uint256, reverting on
                     * overflow (when the input is greater than largest uint136).
                     *
                     * Counterpart to Solidity's `uint136` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 136 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint136(uint256 value) internal pure returns (uint136) {
                        require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
                        return uint136(value);
                    }
                    /**
                     * @dev Returns the downcasted uint128 from uint256, reverting on
                     * overflow (when the input is greater than largest uint128).
                     *
                     * Counterpart to Solidity's `uint128` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 128 bits
                     *
                     * _Available since v2.5._
                     */
                    function toUint128(uint256 value) internal pure returns (uint128) {
                        require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
                        return uint128(value);
                    }
                    /**
                     * @dev Returns the downcasted uint120 from uint256, reverting on
                     * overflow (when the input is greater than largest uint120).
                     *
                     * Counterpart to Solidity's `uint120` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 120 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint120(uint256 value) internal pure returns (uint120) {
                        require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
                        return uint120(value);
                    }
                    /**
                     * @dev Returns the downcasted uint112 from uint256, reverting on
                     * overflow (when the input is greater than largest uint112).
                     *
                     * Counterpart to Solidity's `uint112` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 112 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint112(uint256 value) internal pure returns (uint112) {
                        require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
                        return uint112(value);
                    }
                    /**
                     * @dev Returns the downcasted uint104 from uint256, reverting on
                     * overflow (when the input is greater than largest uint104).
                     *
                     * Counterpart to Solidity's `uint104` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 104 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint104(uint256 value) internal pure returns (uint104) {
                        require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
                        return uint104(value);
                    }
                    /**
                     * @dev Returns the downcasted uint96 from uint256, reverting on
                     * overflow (when the input is greater than largest uint96).
                     *
                     * Counterpart to Solidity's `uint96` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 96 bits
                     *
                     * _Available since v4.2._
                     */
                    function toUint96(uint256 value) internal pure returns (uint96) {
                        require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
                        return uint96(value);
                    }
                    /**
                     * @dev Returns the downcasted uint88 from uint256, reverting on
                     * overflow (when the input is greater than largest uint88).
                     *
                     * Counterpart to Solidity's `uint88` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 88 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint88(uint256 value) internal pure returns (uint88) {
                        require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
                        return uint88(value);
                    }
                    /**
                     * @dev Returns the downcasted uint80 from uint256, reverting on
                     * overflow (when the input is greater than largest uint80).
                     *
                     * Counterpart to Solidity's `uint80` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 80 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint80(uint256 value) internal pure returns (uint80) {
                        require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
                        return uint80(value);
                    }
                    /**
                     * @dev Returns the downcasted uint72 from uint256, reverting on
                     * overflow (when the input is greater than largest uint72).
                     *
                     * Counterpart to Solidity's `uint72` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 72 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint72(uint256 value) internal pure returns (uint72) {
                        require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
                        return uint72(value);
                    }
                    /**
                     * @dev Returns the downcasted uint64 from uint256, reverting on
                     * overflow (when the input is greater than largest uint64).
                     *
                     * Counterpart to Solidity's `uint64` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 64 bits
                     *
                     * _Available since v2.5._
                     */
                    function toUint64(uint256 value) internal pure returns (uint64) {
                        require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
                        return uint64(value);
                    }
                    /**
                     * @dev Returns the downcasted uint56 from uint256, reverting on
                     * overflow (when the input is greater than largest uint56).
                     *
                     * Counterpart to Solidity's `uint56` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 56 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint56(uint256 value) internal pure returns (uint56) {
                        require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
                        return uint56(value);
                    }
                    /**
                     * @dev Returns the downcasted uint48 from uint256, reverting on
                     * overflow (when the input is greater than largest uint48).
                     *
                     * Counterpart to Solidity's `uint48` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 48 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint48(uint256 value) internal pure returns (uint48) {
                        require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
                        return uint48(value);
                    }
                    /**
                     * @dev Returns the downcasted uint40 from uint256, reverting on
                     * overflow (when the input is greater than largest uint40).
                     *
                     * Counterpart to Solidity's `uint40` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 40 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint40(uint256 value) internal pure returns (uint40) {
                        require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
                        return uint40(value);
                    }
                    /**
                     * @dev Returns the downcasted uint32 from uint256, reverting on
                     * overflow (when the input is greater than largest uint32).
                     *
                     * Counterpart to Solidity's `uint32` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 32 bits
                     *
                     * _Available since v2.5._
                     */
                    function toUint32(uint256 value) internal pure returns (uint32) {
                        require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
                        return uint32(value);
                    }
                    /**
                     * @dev Returns the downcasted uint24 from uint256, reverting on
                     * overflow (when the input is greater than largest uint24).
                     *
                     * Counterpart to Solidity's `uint24` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 24 bits
                     *
                     * _Available since v4.7._
                     */
                    function toUint24(uint256 value) internal pure returns (uint24) {
                        require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
                        return uint24(value);
                    }
                    /**
                     * @dev Returns the downcasted uint16 from uint256, reverting on
                     * overflow (when the input is greater than largest uint16).
                     *
                     * Counterpart to Solidity's `uint16` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 16 bits
                     *
                     * _Available since v2.5._
                     */
                    function toUint16(uint256 value) internal pure returns (uint16) {
                        require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
                        return uint16(value);
                    }
                    /**
                     * @dev Returns the downcasted uint8 from uint256, reverting on
                     * overflow (when the input is greater than largest uint8).
                     *
                     * Counterpart to Solidity's `uint8` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 8 bits
                     *
                     * _Available since v2.5._
                     */
                    function toUint8(uint256 value) internal pure returns (uint8) {
                        require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
                        return uint8(value);
                    }
                    /**
                     * @dev Converts a signed int256 into an unsigned uint256.
                     *
                     * Requirements:
                     *
                     * - input must be greater than or equal to 0.
                     *
                     * _Available since v3.0._
                     */
                    function toUint256(int256 value) internal pure returns (uint256) {
                        require(value >= 0, "SafeCast: value must be positive");
                        return uint256(value);
                    }
                    /**
                     * @dev Returns the downcasted int248 from int256, reverting on
                     * overflow (when the input is less than smallest int248 or
                     * greater than largest int248).
                     *
                     * Counterpart to Solidity's `int248` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 248 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt248(int256 value) internal pure returns (int248 downcasted) {
                        downcasted = int248(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 248 bits");
                    }
                    /**
                     * @dev Returns the downcasted int240 from int256, reverting on
                     * overflow (when the input is less than smallest int240 or
                     * greater than largest int240).
                     *
                     * Counterpart to Solidity's `int240` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 240 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt240(int256 value) internal pure returns (int240 downcasted) {
                        downcasted = int240(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 240 bits");
                    }
                    /**
                     * @dev Returns the downcasted int232 from int256, reverting on
                     * overflow (when the input is less than smallest int232 or
                     * greater than largest int232).
                     *
                     * Counterpart to Solidity's `int232` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 232 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt232(int256 value) internal pure returns (int232 downcasted) {
                        downcasted = int232(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 232 bits");
                    }
                    /**
                     * @dev Returns the downcasted int224 from int256, reverting on
                     * overflow (when the input is less than smallest int224 or
                     * greater than largest int224).
                     *
                     * Counterpart to Solidity's `int224` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 224 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt224(int256 value) internal pure returns (int224 downcasted) {
                        downcasted = int224(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 224 bits");
                    }
                    /**
                     * @dev Returns the downcasted int216 from int256, reverting on
                     * overflow (when the input is less than smallest int216 or
                     * greater than largest int216).
                     *
                     * Counterpart to Solidity's `int216` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 216 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt216(int256 value) internal pure returns (int216 downcasted) {
                        downcasted = int216(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 216 bits");
                    }
                    /**
                     * @dev Returns the downcasted int208 from int256, reverting on
                     * overflow (when the input is less than smallest int208 or
                     * greater than largest int208).
                     *
                     * Counterpart to Solidity's `int208` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 208 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt208(int256 value) internal pure returns (int208 downcasted) {
                        downcasted = int208(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 208 bits");
                    }
                    /**
                     * @dev Returns the downcasted int200 from int256, reverting on
                     * overflow (when the input is less than smallest int200 or
                     * greater than largest int200).
                     *
                     * Counterpart to Solidity's `int200` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 200 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt200(int256 value) internal pure returns (int200 downcasted) {
                        downcasted = int200(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 200 bits");
                    }
                    /**
                     * @dev Returns the downcasted int192 from int256, reverting on
                     * overflow (when the input is less than smallest int192 or
                     * greater than largest int192).
                     *
                     * Counterpart to Solidity's `int192` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 192 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt192(int256 value) internal pure returns (int192 downcasted) {
                        downcasted = int192(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 192 bits");
                    }
                    /**
                     * @dev Returns the downcasted int184 from int256, reverting on
                     * overflow (when the input is less than smallest int184 or
                     * greater than largest int184).
                     *
                     * Counterpart to Solidity's `int184` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 184 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt184(int256 value) internal pure returns (int184 downcasted) {
                        downcasted = int184(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 184 bits");
                    }
                    /**
                     * @dev Returns the downcasted int176 from int256, reverting on
                     * overflow (when the input is less than smallest int176 or
                     * greater than largest int176).
                     *
                     * Counterpart to Solidity's `int176` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 176 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt176(int256 value) internal pure returns (int176 downcasted) {
                        downcasted = int176(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 176 bits");
                    }
                    /**
                     * @dev Returns the downcasted int168 from int256, reverting on
                     * overflow (when the input is less than smallest int168 or
                     * greater than largest int168).
                     *
                     * Counterpart to Solidity's `int168` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 168 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt168(int256 value) internal pure returns (int168 downcasted) {
                        downcasted = int168(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 168 bits");
                    }
                    /**
                     * @dev Returns the downcasted int160 from int256, reverting on
                     * overflow (when the input is less than smallest int160 or
                     * greater than largest int160).
                     *
                     * Counterpart to Solidity's `int160` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 160 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt160(int256 value) internal pure returns (int160 downcasted) {
                        downcasted = int160(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 160 bits");
                    }
                    /**
                     * @dev Returns the downcasted int152 from int256, reverting on
                     * overflow (when the input is less than smallest int152 or
                     * greater than largest int152).
                     *
                     * Counterpart to Solidity's `int152` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 152 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt152(int256 value) internal pure returns (int152 downcasted) {
                        downcasted = int152(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 152 bits");
                    }
                    /**
                     * @dev Returns the downcasted int144 from int256, reverting on
                     * overflow (when the input is less than smallest int144 or
                     * greater than largest int144).
                     *
                     * Counterpart to Solidity's `int144` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 144 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt144(int256 value) internal pure returns (int144 downcasted) {
                        downcasted = int144(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 144 bits");
                    }
                    /**
                     * @dev Returns the downcasted int136 from int256, reverting on
                     * overflow (when the input is less than smallest int136 or
                     * greater than largest int136).
                     *
                     * Counterpart to Solidity's `int136` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 136 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt136(int256 value) internal pure returns (int136 downcasted) {
                        downcasted = int136(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 136 bits");
                    }
                    /**
                     * @dev Returns the downcasted int128 from int256, reverting on
                     * overflow (when the input is less than smallest int128 or
                     * greater than largest int128).
                     *
                     * Counterpart to Solidity's `int128` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 128 bits
                     *
                     * _Available since v3.1._
                     */
                    function toInt128(int256 value) internal pure returns (int128 downcasted) {
                        downcasted = int128(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 128 bits");
                    }
                    /**
                     * @dev Returns the downcasted int120 from int256, reverting on
                     * overflow (when the input is less than smallest int120 or
                     * greater than largest int120).
                     *
                     * Counterpart to Solidity's `int120` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 120 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt120(int256 value) internal pure returns (int120 downcasted) {
                        downcasted = int120(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 120 bits");
                    }
                    /**
                     * @dev Returns the downcasted int112 from int256, reverting on
                     * overflow (when the input is less than smallest int112 or
                     * greater than largest int112).
                     *
                     * Counterpart to Solidity's `int112` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 112 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt112(int256 value) internal pure returns (int112 downcasted) {
                        downcasted = int112(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 112 bits");
                    }
                    /**
                     * @dev Returns the downcasted int104 from int256, reverting on
                     * overflow (when the input is less than smallest int104 or
                     * greater than largest int104).
                     *
                     * Counterpart to Solidity's `int104` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 104 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt104(int256 value) internal pure returns (int104 downcasted) {
                        downcasted = int104(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 104 bits");
                    }
                    /**
                     * @dev Returns the downcasted int96 from int256, reverting on
                     * overflow (when the input is less than smallest int96 or
                     * greater than largest int96).
                     *
                     * Counterpart to Solidity's `int96` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 96 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt96(int256 value) internal pure returns (int96 downcasted) {
                        downcasted = int96(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 96 bits");
                    }
                    /**
                     * @dev Returns the downcasted int88 from int256, reverting on
                     * overflow (when the input is less than smallest int88 or
                     * greater than largest int88).
                     *
                     * Counterpart to Solidity's `int88` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 88 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt88(int256 value) internal pure returns (int88 downcasted) {
                        downcasted = int88(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 88 bits");
                    }
                    /**
                     * @dev Returns the downcasted int80 from int256, reverting on
                     * overflow (when the input is less than smallest int80 or
                     * greater than largest int80).
                     *
                     * Counterpart to Solidity's `int80` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 80 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt80(int256 value) internal pure returns (int80 downcasted) {
                        downcasted = int80(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 80 bits");
                    }
                    /**
                     * @dev Returns the downcasted int72 from int256, reverting on
                     * overflow (when the input is less than smallest int72 or
                     * greater than largest int72).
                     *
                     * Counterpart to Solidity's `int72` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 72 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt72(int256 value) internal pure returns (int72 downcasted) {
                        downcasted = int72(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 72 bits");
                    }
                    /**
                     * @dev Returns the downcasted int64 from int256, reverting on
                     * overflow (when the input is less than smallest int64 or
                     * greater than largest int64).
                     *
                     * Counterpart to Solidity's `int64` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 64 bits
                     *
                     * _Available since v3.1._
                     */
                    function toInt64(int256 value) internal pure returns (int64 downcasted) {
                        downcasted = int64(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 64 bits");
                    }
                    /**
                     * @dev Returns the downcasted int56 from int256, reverting on
                     * overflow (when the input is less than smallest int56 or
                     * greater than largest int56).
                     *
                     * Counterpart to Solidity's `int56` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 56 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt56(int256 value) internal pure returns (int56 downcasted) {
                        downcasted = int56(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 56 bits");
                    }
                    /**
                     * @dev Returns the downcasted int48 from int256, reverting on
                     * overflow (when the input is less than smallest int48 or
                     * greater than largest int48).
                     *
                     * Counterpart to Solidity's `int48` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 48 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt48(int256 value) internal pure returns (int48 downcasted) {
                        downcasted = int48(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 48 bits");
                    }
                    /**
                     * @dev Returns the downcasted int40 from int256, reverting on
                     * overflow (when the input is less than smallest int40 or
                     * greater than largest int40).
                     *
                     * Counterpart to Solidity's `int40` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 40 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt40(int256 value) internal pure returns (int40 downcasted) {
                        downcasted = int40(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 40 bits");
                    }
                    /**
                     * @dev Returns the downcasted int32 from int256, reverting on
                     * overflow (when the input is less than smallest int32 or
                     * greater than largest int32).
                     *
                     * Counterpart to Solidity's `int32` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 32 bits
                     *
                     * _Available since v3.1._
                     */
                    function toInt32(int256 value) internal pure returns (int32 downcasted) {
                        downcasted = int32(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 32 bits");
                    }
                    /**
                     * @dev Returns the downcasted int24 from int256, reverting on
                     * overflow (when the input is less than smallest int24 or
                     * greater than largest int24).
                     *
                     * Counterpart to Solidity's `int24` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 24 bits
                     *
                     * _Available since v4.7._
                     */
                    function toInt24(int256 value) internal pure returns (int24 downcasted) {
                        downcasted = int24(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 24 bits");
                    }
                    /**
                     * @dev Returns the downcasted int16 from int256, reverting on
                     * overflow (when the input is less than smallest int16 or
                     * greater than largest int16).
                     *
                     * Counterpart to Solidity's `int16` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 16 bits
                     *
                     * _Available since v3.1._
                     */
                    function toInt16(int256 value) internal pure returns (int16 downcasted) {
                        downcasted = int16(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 16 bits");
                    }
                    /**
                     * @dev Returns the downcasted int8 from int256, reverting on
                     * overflow (when the input is less than smallest int8 or
                     * greater than largest int8).
                     *
                     * Counterpart to Solidity's `int8` operator.
                     *
                     * Requirements:
                     *
                     * - input must fit into 8 bits
                     *
                     * _Available since v3.1._
                     */
                    function toInt8(int256 value) internal pure returns (int8 downcasted) {
                        downcasted = int8(value);
                        require(downcasted == value, "SafeCast: value doesn't fit in 8 bits");
                    }
                    /**
                     * @dev Converts an unsigned uint256 into a signed int256.
                     *
                     * Requirements:
                     *
                     * - input must be less than or equal to maxInt256.
                     *
                     * _Available since v3.0._
                     */
                    function toInt256(uint256 value) internal pure returns (int256) {
                        // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
                        require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
                        return int256(value);
                    }
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Simple single owner authorization mixin.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/auth/Owned.sol)
                abstract contract Owned {
                    /*//////////////////////////////////////////////////////////////
                                                 EVENTS
                    //////////////////////////////////////////////////////////////*/
                    event OwnershipTransferred(address indexed user, address indexed newOwner);
                    /*//////////////////////////////////////////////////////////////
                                            OWNERSHIP STORAGE
                    //////////////////////////////////////////////////////////////*/
                    address public owner;
                    modifier onlyOwner() virtual {
                        require(msg.sender == owner, "UNAUTHORIZED");
                        _;
                    }
                    /*//////////////////////////////////////////////////////////////
                                               CONSTRUCTOR
                    //////////////////////////////////////////////////////////////*/
                    constructor(address _owner) {
                        owner = _owner;
                        emit OwnershipTransferred(address(0), _owner);
                    }
                    /*//////////////////////////////////////////////////////////////
                                             OWNERSHIP LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function transferOwnership(address newOwner) public virtual onlyOwner {
                        owner = newOwner;
                        emit OwnershipTransferred(msg.sender, newOwner);
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {ResolvedOrder, OutputToken} from "../base/ReactorStructs.sol";
                /// @notice Interface for getting fee outputs
                interface IProtocolFeeController {
                    /// @notice Get fee outputs for the given orders
                    /// @param order The orders to get fee outputs for
                    /// @return List of fee outputs to append for each provided order
                    function getFeeOutputs(ResolvedOrder memory order) external view returns (OutputToken[] memory);
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                interface IEIP712 {
                    function DOMAIN_SEPARATOR() external view returns (bytes32);
                }
                

                File 6 of 7: Permit2
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
                /// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
                /// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
                abstract contract ERC20 {
                    /*//////////////////////////////////////////////////////////////
                                                 EVENTS
                    //////////////////////////////////////////////////////////////*/
                    event Transfer(address indexed from, address indexed to, uint256 amount);
                    event Approval(address indexed owner, address indexed spender, uint256 amount);
                    /*//////////////////////////////////////////////////////////////
                                            METADATA STORAGE
                    //////////////////////////////////////////////////////////////*/
                    string public name;
                    string public symbol;
                    uint8 public immutable decimals;
                    /*//////////////////////////////////////////////////////////////
                                              ERC20 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 public totalSupply;
                    mapping(address => uint256) public balanceOf;
                    mapping(address => mapping(address => uint256)) public allowance;
                    /*//////////////////////////////////////////////////////////////
                                            EIP-2612 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 internal immutable INITIAL_CHAIN_ID;
                    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
                    mapping(address => uint256) public nonces;
                    /*//////////////////////////////////////////////////////////////
                                               CONSTRUCTOR
                    //////////////////////////////////////////////////////////////*/
                    constructor(
                        string memory _name,
                        string memory _symbol,
                        uint8 _decimals
                    ) {
                        name = _name;
                        symbol = _symbol;
                        decimals = _decimals;
                        INITIAL_CHAIN_ID = block.chainid;
                        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
                    }
                    /*//////////////////////////////////////////////////////////////
                                               ERC20 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function approve(address spender, uint256 amount) public virtual returns (bool) {
                        allowance[msg.sender][spender] = amount;
                        emit Approval(msg.sender, spender, amount);
                        return true;
                    }
                    function transfer(address to, uint256 amount) public virtual returns (bool) {
                        balanceOf[msg.sender] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(msg.sender, to, amount);
                        return true;
                    }
                    function transferFrom(
                        address from,
                        address to,
                        uint256 amount
                    ) public virtual returns (bool) {
                        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
                        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
                        balanceOf[from] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(from, to, amount);
                        return true;
                    }
                    /*//////////////////////////////////////////////////////////////
                                             EIP-2612 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function permit(
                        address owner,
                        address spender,
                        uint256 value,
                        uint256 deadline,
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) public virtual {
                        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
                        // Unchecked because the only math done is incrementing
                        // the owner's nonce which cannot realistically overflow.
                        unchecked {
                            address recoveredAddress = ecrecover(
                                keccak256(
                                    abi.encodePacked(
                                        "\\x19\\x01",
                                        DOMAIN_SEPARATOR(),
                                        keccak256(
                                            abi.encode(
                                                keccak256(
                                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                                ),
                                                owner,
                                                spender,
                                                value,
                                                nonces[owner]++,
                                                deadline
                                            )
                                        )
                                    )
                                ),
                                v,
                                r,
                                s
                            );
                            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
                            allowance[recoveredAddress][spender] = value;
                        }
                        emit Approval(owner, spender, value);
                    }
                    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
                        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
                    }
                    function computeDomainSeparator() internal view virtual returns (bytes32) {
                        return
                            keccak256(
                                abi.encode(
                                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                                    keccak256(bytes(name)),
                                    keccak256("1"),
                                    block.chainid,
                                    address(this)
                                )
                            );
                    }
                    /*//////////////////////////////////////////////////////////////
                                        INTERNAL MINT/BURN LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function _mint(address to, uint256 amount) internal virtual {
                        totalSupply += amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(address(0), to, amount);
                    }
                    function _burn(address from, uint256 amount) internal virtual {
                        balanceOf[from] -= amount;
                        // Cannot underflow because a user's balance
                        // will never be larger than the total supply.
                        unchecked {
                            totalSupply -= amount;
                        }
                        emit Transfer(from, address(0), amount);
                    }
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                import {ERC20} from "../tokens/ERC20.sol";
                /// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
                /// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
                /// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
                library SafeTransferLib {
                    /*//////////////////////////////////////////////////////////////
                                             ETH OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferETH(address to, uint256 amount) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Transfer the ETH and store if it succeeded or not.
                            success := call(gas(), to, amount, 0, 0, 0, 0)
                        }
                        require(success, "ETH_TRANSFER_FAILED");
                    }
                    /*//////////////////////////////////////////////////////////////
                                            ERC20 OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferFrom(
                        ERC20 token,
                        address from,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), from) // Append the "from" argument.
                            mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
                            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FROM_FAILED");
                    }
                    function safeTransfer(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FAILED");
                    }
                    function safeApprove(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "APPROVE_FAILED");
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity 0.8.17;
                import {ERC20} from "solmate/tokens/ERC20.sol";
                import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
                import {PermitHash} from "./libraries/PermitHash.sol";
                import {SignatureVerification} from "./libraries/SignatureVerification.sol";
                import {EIP712} from "./EIP712.sol";
                import {IAllowanceTransfer} from "../src/interfaces/IAllowanceTransfer.sol";
                import {SignatureExpired, InvalidNonce} from "./PermitErrors.sol";
                import {Allowance} from "./libraries/Allowance.sol";
                contract AllowanceTransfer is IAllowanceTransfer, EIP712 {
                    using SignatureVerification for bytes;
                    using SafeTransferLib for ERC20;
                    using PermitHash for PermitSingle;
                    using PermitHash for PermitBatch;
                    using Allowance for PackedAllowance;
                    /// @notice Maps users to tokens to spender addresses and information about the approval on the token
                    /// @dev Indexed in the order of token owner address, token address, spender address
                    /// @dev The stored word saves the allowed amount, expiration on the allowance, and nonce
                    mapping(address => mapping(address => mapping(address => PackedAllowance))) public allowance;
                    /// @inheritdoc IAllowanceTransfer
                    function approve(address token, address spender, uint160 amount, uint48 expiration) external {
                        PackedAllowance storage allowed = allowance[msg.sender][token][spender];
                        allowed.updateAmountAndExpiration(amount, expiration);
                        emit Approval(msg.sender, token, spender, amount, expiration);
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external {
                        if (block.timestamp > permitSingle.sigDeadline) revert SignatureExpired(permitSingle.sigDeadline);
                        // Verify the signer address from the signature.
                        signature.verify(_hashTypedData(permitSingle.hash()), owner);
                        _updateApproval(permitSingle.details, owner, permitSingle.spender);
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external {
                        if (block.timestamp > permitBatch.sigDeadline) revert SignatureExpired(permitBatch.sigDeadline);
                        // Verify the signer address from the signature.
                        signature.verify(_hashTypedData(permitBatch.hash()), owner);
                        address spender = permitBatch.spender;
                        unchecked {
                            uint256 length = permitBatch.details.length;
                            for (uint256 i = 0; i < length; ++i) {
                                _updateApproval(permitBatch.details[i], owner, spender);
                            }
                        }
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function transferFrom(address from, address to, uint160 amount, address token) external {
                        _transfer(from, to, amount, token);
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external {
                        unchecked {
                            uint256 length = transferDetails.length;
                            for (uint256 i = 0; i < length; ++i) {
                                AllowanceTransferDetails memory transferDetail = transferDetails[i];
                                _transfer(transferDetail.from, transferDetail.to, transferDetail.amount, transferDetail.token);
                            }
                        }
                    }
                    /// @notice Internal function for transferring tokens using stored allowances
                    /// @dev Will fail if the allowed timeframe has passed
                    function _transfer(address from, address to, uint160 amount, address token) private {
                        PackedAllowance storage allowed = allowance[from][token][msg.sender];
                        if (block.timestamp > allowed.expiration) revert AllowanceExpired(allowed.expiration);
                        uint256 maxAmount = allowed.amount;
                        if (maxAmount != type(uint160).max) {
                            if (amount > maxAmount) {
                                revert InsufficientAllowance(maxAmount);
                            } else {
                                unchecked {
                                    allowed.amount = uint160(maxAmount) - amount;
                                }
                            }
                        }
                        // Transfer the tokens from the from address to the recipient.
                        ERC20(token).safeTransferFrom(from, to, amount);
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function lockdown(TokenSpenderPair[] calldata approvals) external {
                        address owner = msg.sender;
                        // Revoke allowances for each pair of spenders and tokens.
                        unchecked {
                            uint256 length = approvals.length;
                            for (uint256 i = 0; i < length; ++i) {
                                address token = approvals[i].token;
                                address spender = approvals[i].spender;
                                allowance[owner][token][spender].amount = 0;
                                emit Lockdown(owner, token, spender);
                            }
                        }
                    }
                    /// @inheritdoc IAllowanceTransfer
                    function invalidateNonces(address token, address spender, uint48 newNonce) external {
                        uint48 oldNonce = allowance[msg.sender][token][spender].nonce;
                        if (newNonce <= oldNonce) revert InvalidNonce();
                        // Limit the amount of nonces that can be invalidated in one transaction.
                        unchecked {
                            uint48 delta = newNonce - oldNonce;
                            if (delta > type(uint16).max) revert ExcessiveInvalidation();
                        }
                        allowance[msg.sender][token][spender].nonce = newNonce;
                        emit NonceInvalidation(msg.sender, token, spender, newNonce, oldNonce);
                    }
                    /// @notice Sets the new values for amount, expiration, and nonce.
                    /// @dev Will check that the signed nonce is equal to the current nonce and then incrememnt the nonce value by 1.
                    /// @dev Emits a Permit event.
                    function _updateApproval(PermitDetails memory details, address owner, address spender) private {
                        uint48 nonce = details.nonce;
                        address token = details.token;
                        uint160 amount = details.amount;
                        uint48 expiration = details.expiration;
                        PackedAllowance storage allowed = allowance[owner][token][spender];
                        if (allowed.nonce != nonce) revert InvalidNonce();
                        allowed.updateAll(amount, expiration, nonce);
                        emit Permit(owner, token, spender, amount, expiration, nonce);
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity 0.8.17;
                /// @notice EIP712 helpers for permit2
                /// @dev Maintains cross-chain replay protection in the event of a fork
                /// @dev Reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/EIP712.sol
                contract EIP712 {
                    // Cache the domain separator as an immutable value, but also store the chain id that it
                    // corresponds to, in order to invalidate the cached domain separator if the chain id changes.
                    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
                    uint256 private immutable _CACHED_CHAIN_ID;
                    bytes32 private constant _HASHED_NAME = keccak256("Permit2");
                    bytes32 private constant _TYPE_HASH =
                        keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
                    constructor() {
                        _CACHED_CHAIN_ID = block.chainid;
                        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME);
                    }
                    /// @notice Returns the domain separator for the current chain.
                    /// @dev Uses cached version if chainid and address are unchanged from construction.
                    function DOMAIN_SEPARATOR() public view returns (bytes32) {
                        return block.chainid == _CACHED_CHAIN_ID
                            ? _CACHED_DOMAIN_SEPARATOR
                            : _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME);
                    }
                    /// @notice Builds a domain separator using the current chainId and contract address.
                    function _buildDomainSeparator(bytes32 typeHash, bytes32 nameHash) private view returns (bytes32) {
                        return keccak256(abi.encode(typeHash, nameHash, block.chainid, address(this)));
                    }
                    /// @notice Creates an EIP-712 typed data hash
                    function _hashTypedData(bytes32 dataHash) internal view returns (bytes32) {
                        return keccak256(abi.encodePacked("\\x19\\x01", DOMAIN_SEPARATOR(), dataHash));
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity 0.8.17;
                import {SignatureTransfer} from "./SignatureTransfer.sol";
                import {AllowanceTransfer} from "./AllowanceTransfer.sol";
                /// @notice Permit2 handles signature-based transfers in SignatureTransfer and allowance-based transfers in AllowanceTransfer.
                /// @dev Users must approve Permit2 before calling any of the transfer functions.
                contract Permit2 is SignatureTransfer, AllowanceTransfer {
                // Permit2 unifies the two contracts so users have maximal flexibility with their approval.
                }
                // SPDX-License-Identifier: MIT
                pragma solidity 0.8.17;
                /// @notice Shared errors between signature based transfers and allowance based transfers.
                /// @notice Thrown when validating an inputted signature that is stale
                /// @param signatureDeadline The timestamp at which a signature is no longer valid
                error SignatureExpired(uint256 signatureDeadline);
                /// @notice Thrown when validating that the inputted nonce has not been used
                error InvalidNonce();
                // SPDX-License-Identifier: MIT
                pragma solidity 0.8.17;
                import {ISignatureTransfer} from "./interfaces/ISignatureTransfer.sol";
                import {SignatureExpired, InvalidNonce} from "./PermitErrors.sol";
                import {ERC20} from "solmate/tokens/ERC20.sol";
                import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
                import {SignatureVerification} from "./libraries/SignatureVerification.sol";
                import {PermitHash} from "./libraries/PermitHash.sol";
                import {EIP712} from "./EIP712.sol";
                contract SignatureTransfer is ISignatureTransfer, EIP712 {
                    using SignatureVerification for bytes;
                    using SafeTransferLib for ERC20;
                    using PermitHash for PermitTransferFrom;
                    using PermitHash for PermitBatchTransferFrom;
                    /// @inheritdoc ISignatureTransfer
                    mapping(address => mapping(uint256 => uint256)) public nonceBitmap;
                    /// @inheritdoc ISignatureTransfer
                    function permitTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external {
                        _permitTransferFrom(permit, transferDetails, owner, permit.hash(), signature);
                    }
                    /// @inheritdoc ISignatureTransfer
                    function permitWitnessTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external {
                        _permitTransferFrom(
                            permit, transferDetails, owner, permit.hashWithWitness(witness, witnessTypeString), signature
                        );
                    }
                    /// @notice Transfers a token using a signed permit message.
                    /// @dev If to is the zero address, the tokens are sent to the spender.
                    /// @param permit The permit data signed over by the owner
                    /// @param dataHash The EIP-712 hash of permit data to include when checking signature
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails The spender's requested transfer details for the permitted token
                    /// @param signature The signature to verify
                    function _permitTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes32 dataHash,
                        bytes calldata signature
                    ) private {
                        uint256 requestedAmount = transferDetails.requestedAmount;
                        if (block.timestamp > permit.deadline) revert SignatureExpired(permit.deadline);
                        if (requestedAmount > permit.permitted.amount) revert InvalidAmount(permit.permitted.amount);
                        _useUnorderedNonce(owner, permit.nonce);
                        signature.verify(_hashTypedData(dataHash), owner);
                        ERC20(permit.permitted.token).safeTransferFrom(owner, transferDetails.to, requestedAmount);
                    }
                    /// @inheritdoc ISignatureTransfer
                    function permitTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external {
                        _permitTransferFrom(permit, transferDetails, owner, permit.hash(), signature);
                    }
                    /// @inheritdoc ISignatureTransfer
                    function permitWitnessTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external {
                        _permitTransferFrom(
                            permit, transferDetails, owner, permit.hashWithWitness(witness, witnessTypeString), signature
                        );
                    }
                    /// @notice Transfers tokens using a signed permit messages
                    /// @dev If to is the zero address, the tokens are sent to the spender
                    /// @param permit The permit data signed over by the owner
                    /// @param dataHash The EIP-712 hash of permit data to include when checking signature
                    /// @param owner The owner of the tokens to transfer
                    /// @param signature The signature to verify
                    function _permitTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes32 dataHash,
                        bytes calldata signature
                    ) private {
                        uint256 numPermitted = permit.permitted.length;
                        if (block.timestamp > permit.deadline) revert SignatureExpired(permit.deadline);
                        if (numPermitted != transferDetails.length) revert LengthMismatch();
                        _useUnorderedNonce(owner, permit.nonce);
                        signature.verify(_hashTypedData(dataHash), owner);
                        unchecked {
                            for (uint256 i = 0; i < numPermitted; ++i) {
                                TokenPermissions memory permitted = permit.permitted[i];
                                uint256 requestedAmount = transferDetails[i].requestedAmount;
                                if (requestedAmount > permitted.amount) revert InvalidAmount(permitted.amount);
                                if (requestedAmount != 0) {
                                    // allow spender to specify which of the permitted tokens should be transferred
                                    ERC20(permitted.token).safeTransferFrom(owner, transferDetails[i].to, requestedAmount);
                                }
                            }
                        }
                    }
                    /// @inheritdoc ISignatureTransfer
                    function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external {
                        nonceBitmap[msg.sender][wordPos] |= mask;
                        emit UnorderedNonceInvalidation(msg.sender, wordPos, mask);
                    }
                    /// @notice Returns the index of the bitmap and the bit position within the bitmap. Used for unordered nonces
                    /// @param nonce The nonce to get the associated word and bit positions
                    /// @return wordPos The word position or index into the nonceBitmap
                    /// @return bitPos The bit position
                    /// @dev The first 248 bits of the nonce value is the index of the desired bitmap
                    /// @dev The last 8 bits of the nonce value is the position of the bit in the bitmap
                    function bitmapPositions(uint256 nonce) private pure returns (uint256 wordPos, uint256 bitPos) {
                        wordPos = uint248(nonce >> 8);
                        bitPos = uint8(nonce);
                    }
                    /// @notice Checks whether a nonce is taken and sets the bit at the bit position in the bitmap at the word position
                    /// @param from The address to use the nonce at
                    /// @param nonce The nonce to spend
                    function _useUnorderedNonce(address from, uint256 nonce) internal {
                        (uint256 wordPos, uint256 bitPos) = bitmapPositions(nonce);
                        uint256 bit = 1 << bitPos;
                        uint256 flipped = nonceBitmap[from][wordPos] ^= bit;
                        if (flipped & bit == 0) revert InvalidNonce();
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                /// @title AllowanceTransfer
                /// @notice Handles ERC20 token permissions through signature based allowance setting and ERC20 token transfers by checking allowed amounts
                /// @dev Requires user's token approval on the Permit2 contract
                interface IAllowanceTransfer {
                    /// @notice Thrown when an allowance on a token has expired.
                    /// @param deadline The timestamp at which the allowed amount is no longer valid
                    error AllowanceExpired(uint256 deadline);
                    /// @notice Thrown when an allowance on a token has been depleted.
                    /// @param amount The maximum amount allowed
                    error InsufficientAllowance(uint256 amount);
                    /// @notice Thrown when too many nonces are invalidated.
                    error ExcessiveInvalidation();
                    /// @notice Emits an event when the owner successfully invalidates an ordered nonce.
                    event NonceInvalidation(
                        address indexed owner, address indexed token, address indexed spender, uint48 newNonce, uint48 oldNonce
                    );
                    /// @notice Emits an event when the owner successfully sets permissions on a token for the spender.
                    event Approval(
                        address indexed owner, address indexed token, address indexed spender, uint160 amount, uint48 expiration
                    );
                    /// @notice Emits an event when the owner successfully sets permissions using a permit signature on a token for the spender.
                    event Permit(
                        address indexed owner,
                        address indexed token,
                        address indexed spender,
                        uint160 amount,
                        uint48 expiration,
                        uint48 nonce
                    );
                    /// @notice Emits an event when the owner sets the allowance back to 0 with the lockdown function.
                    event Lockdown(address indexed owner, address token, address spender);
                    /// @notice The permit data for a token
                    struct PermitDetails {
                        // ERC20 token address
                        address token;
                        // the maximum amount allowed to spend
                        uint160 amount;
                        // timestamp at which a spender's token allowances become invalid
                        uint48 expiration;
                        // an incrementing value indexed per owner,token,and spender for each signature
                        uint48 nonce;
                    }
                    /// @notice The permit message signed for a single token allownce
                    struct PermitSingle {
                        // the permit data for a single token alownce
                        PermitDetails details;
                        // address permissioned on the allowed tokens
                        address spender;
                        // deadline on the permit signature
                        uint256 sigDeadline;
                    }
                    /// @notice The permit message signed for multiple token allowances
                    struct PermitBatch {
                        // the permit data for multiple token allowances
                        PermitDetails[] details;
                        // address permissioned on the allowed tokens
                        address spender;
                        // deadline on the permit signature
                        uint256 sigDeadline;
                    }
                    /// @notice The saved permissions
                    /// @dev This info is saved per owner, per token, per spender and all signed over in the permit message
                    /// @dev Setting amount to type(uint160).max sets an unlimited approval
                    struct PackedAllowance {
                        // amount allowed
                        uint160 amount;
                        // permission expiry
                        uint48 expiration;
                        // an incrementing value indexed per owner,token,and spender for each signature
                        uint48 nonce;
                    }
                    /// @notice A token spender pair.
                    struct TokenSpenderPair {
                        // the token the spender is approved
                        address token;
                        // the spender address
                        address spender;
                    }
                    /// @notice Details for a token transfer.
                    struct AllowanceTransferDetails {
                        // the owner of the token
                        address from;
                        // the recipient of the token
                        address to;
                        // the amount of the token
                        uint160 amount;
                        // the token to be transferred
                        address token;
                    }
                    /// @notice A mapping from owner address to token address to spender address to PackedAllowance struct, which contains details and conditions of the approval.
                    /// @notice The mapping is indexed in the above order see: allowance[ownerAddress][tokenAddress][spenderAddress]
                    /// @dev The packed slot holds the allowed amount, expiration at which the allowed amount is no longer valid, and current nonce thats updated on any signature based approvals.
                    function allowance(address, address, address) external view returns (uint160, uint48, uint48);
                    /// @notice Approves the spender to use up to amount of the specified token up until the expiration
                    /// @param token The token to approve
                    /// @param spender The spender address to approve
                    /// @param amount The approved amount of the token
                    /// @param expiration The timestamp at which the approval is no longer valid
                    /// @dev The packed allowance also holds a nonce, which will stay unchanged in approve
                    /// @dev Setting amount to type(uint160).max sets an unlimited approval
                    function approve(address token, address spender, uint160 amount, uint48 expiration) external;
                    /// @notice Permit a spender to a given amount of the owners token via the owner's EIP-712 signature
                    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
                    /// @param owner The owner of the tokens being approved
                    /// @param permitSingle Data signed over by the owner specifying the terms of approval
                    /// @param signature The owner's signature over the permit data
                    function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external;
                    /// @notice Permit a spender to the signed amounts of the owners tokens via the owner's EIP-712 signature
                    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
                    /// @param owner The owner of the tokens being approved
                    /// @param permitBatch Data signed over by the owner specifying the terms of approval
                    /// @param signature The owner's signature over the permit data
                    function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external;
                    /// @notice Transfer approved tokens from one address to another
                    /// @param from The address to transfer from
                    /// @param to The address of the recipient
                    /// @param amount The amount of the token to transfer
                    /// @param token The token address to transfer
                    /// @dev Requires the from address to have approved at least the desired amount
                    /// of tokens to msg.sender.
                    function transferFrom(address from, address to, uint160 amount, address token) external;
                    /// @notice Transfer approved tokens in a batch
                    /// @param transferDetails Array of owners, recipients, amounts, and tokens for the transfers
                    /// @dev Requires the from addresses to have approved at least the desired amount
                    /// of tokens to msg.sender.
                    function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external;
                    /// @notice Enables performing a "lockdown" of the sender's Permit2 identity
                    /// by batch revoking approvals
                    /// @param approvals Array of approvals to revoke.
                    function lockdown(TokenSpenderPair[] calldata approvals) external;
                    /// @notice Invalidate nonces for a given (token, spender) pair
                    /// @param token The token to invalidate nonces for
                    /// @param spender The spender to invalidate nonces for
                    /// @param newNonce The new nonce to set. Invalidates all nonces less than it.
                    /// @dev Can't invalidate more than 2**16 nonces per transaction.
                    function invalidateNonces(address token, address spender, uint48 newNonce) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                interface IERC1271 {
                    /// @dev Should return whether the signature provided is valid for the provided data
                    /// @param hash      Hash of the data to be signed
                    /// @param signature Signature byte array associated with _data
                    /// @return magicValue The bytes4 magic value 0x1626ba7e
                    function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                /// @title SignatureTransfer
                /// @notice Handles ERC20 token transfers through signature based actions
                /// @dev Requires user's token approval on the Permit2 contract
                interface ISignatureTransfer {
                    /// @notice Thrown when the requested amount for a transfer is larger than the permissioned amount
                    /// @param maxAmount The maximum amount a spender can request to transfer
                    error InvalidAmount(uint256 maxAmount);
                    /// @notice Thrown when the number of tokens permissioned to a spender does not match the number of tokens being transferred
                    /// @dev If the spender does not need to transfer the number of tokens permitted, the spender can request amount 0 to be transferred
                    error LengthMismatch();
                    /// @notice Emits an event when the owner successfully invalidates an unordered nonce.
                    event UnorderedNonceInvalidation(address indexed owner, uint256 word, uint256 mask);
                    /// @notice The token and amount details for a transfer signed in the permit transfer signature
                    struct TokenPermissions {
                        // ERC20 token address
                        address token;
                        // the maximum amount that can be spent
                        uint256 amount;
                    }
                    /// @notice The signed permit message for a single token transfer
                    struct PermitTransferFrom {
                        TokenPermissions permitted;
                        // a unique value for every token owner's signature to prevent signature replays
                        uint256 nonce;
                        // deadline on the permit signature
                        uint256 deadline;
                    }
                    /// @notice Specifies the recipient address and amount for batched transfers.
                    /// @dev Recipients and amounts correspond to the index of the signed token permissions array.
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount.
                    struct SignatureTransferDetails {
                        // recipient address
                        address to;
                        // spender requested amount
                        uint256 requestedAmount;
                    }
                    /// @notice Used to reconstruct the signed permit message for multiple token transfers
                    /// @dev Do not need to pass in spender address as it is required that it is msg.sender
                    /// @dev Note that a user still signs over a spender address
                    struct PermitBatchTransferFrom {
                        // the tokens and corresponding amounts permitted for a transfer
                        TokenPermissions[] permitted;
                        // a unique value for every token owner's signature to prevent signature replays
                        uint256 nonce;
                        // deadline on the permit signature
                        uint256 deadline;
                    }
                    /// @notice A map from token owner address and a caller specified word index to a bitmap. Used to set bits in the bitmap to prevent against signature replay protection
                    /// @dev Uses unordered nonces so that permit messages do not need to be spent in a certain order
                    /// @dev The mapping is indexed first by the token owner, then by an index specified in the nonce
                    /// @dev It returns a uint256 bitmap
                    /// @dev The index, or wordPosition is capped at type(uint248).max
                    function nonceBitmap(address, uint256) external view returns (uint256);
                    /// @notice Transfers a token using a signed permit message
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails The spender's requested transfer details for the permitted token
                    /// @param signature The signature to verify
                    function permitTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers a token using a signed permit message
                    /// @notice Includes extra data provided by the caller to verify signature over
                    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
                    /// @dev Reverts if the requested amount is greater than the permitted signed amount
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails The spender's requested transfer details for the permitted token
                    /// @param witness Extra data to include when checking the user signature
                    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
                    /// @param signature The signature to verify
                    function permitWitnessTransferFrom(
                        PermitTransferFrom memory permit,
                        SignatureTransferDetails calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers multiple tokens using a signed permit message
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
                    /// @param signature The signature to verify
                    function permitTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes calldata signature
                    ) external;
                    /// @notice Transfers multiple tokens using a signed permit message
                    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
                    /// @notice Includes extra data provided by the caller to verify signature over
                    /// @param permit The permit data signed over by the owner
                    /// @param owner The owner of the tokens to transfer
                    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
                    /// @param witness Extra data to include when checking the user signature
                    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
                    /// @param signature The signature to verify
                    function permitWitnessTransferFrom(
                        PermitBatchTransferFrom memory permit,
                        SignatureTransferDetails[] calldata transferDetails,
                        address owner,
                        bytes32 witness,
                        string calldata witnessTypeString,
                        bytes calldata signature
                    ) external;
                    /// @notice Invalidates the bits specified in mask for the bitmap at the word position
                    /// @dev The wordPos is maxed at type(uint248).max
                    /// @param wordPos A number to index the nonceBitmap at
                    /// @param mask A bitmap masked against msg.sender's current bitmap at the word position
                    function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                import {IAllowanceTransfer} from "../interfaces/IAllowanceTransfer.sol";
                library Allowance {
                    // note if the expiration passed is 0, then it the approval set to the block.timestamp
                    uint256 private constant BLOCK_TIMESTAMP_EXPIRATION = 0;
                    /// @notice Sets the allowed amount, expiry, and nonce of the spender's permissions on owner's token.
                    /// @dev Nonce is incremented.
                    /// @dev If the inputted expiration is 0, the stored expiration is set to block.timestamp
                    function updateAll(
                        IAllowanceTransfer.PackedAllowance storage allowed,
                        uint160 amount,
                        uint48 expiration,
                        uint48 nonce
                    ) internal {
                        uint48 storedNonce;
                        unchecked {
                            storedNonce = nonce + 1;
                        }
                        uint48 storedExpiration = expiration == BLOCK_TIMESTAMP_EXPIRATION ? uint48(block.timestamp) : expiration;
                        uint256 word = pack(amount, storedExpiration, storedNonce);
                        assembly {
                            sstore(allowed.slot, word)
                        }
                    }
                    /// @notice Sets the allowed amount and expiry of the spender's permissions on owner's token.
                    /// @dev Nonce does not need to be incremented.
                    function updateAmountAndExpiration(
                        IAllowanceTransfer.PackedAllowance storage allowed,
                        uint160 amount,
                        uint48 expiration
                    ) internal {
                        // If the inputted expiration is 0, the allowance only lasts the duration of the block.
                        allowed.expiration = expiration == 0 ? uint48(block.timestamp) : expiration;
                        allowed.amount = amount;
                    }
                    /// @notice Computes the packed slot of the amount, expiration, and nonce that make up PackedAllowance
                    function pack(uint160 amount, uint48 expiration, uint48 nonce) internal pure returns (uint256 word) {
                        word = (uint256(nonce) << 208) | uint256(expiration) << 160 | amount;
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                import {IAllowanceTransfer} from "../interfaces/IAllowanceTransfer.sol";
                import {ISignatureTransfer} from "../interfaces/ISignatureTransfer.sol";
                library PermitHash {
                    bytes32 public constant _PERMIT_DETAILS_TYPEHASH =
                        keccak256("PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)");
                    bytes32 public constant _PERMIT_SINGLE_TYPEHASH = keccak256(
                        "PermitSingle(PermitDetails details,address spender,uint256 sigDeadline)PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)"
                    );
                    bytes32 public constant _PERMIT_BATCH_TYPEHASH = keccak256(
                        "PermitBatch(PermitDetails[] details,address spender,uint256 sigDeadline)PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)"
                    );
                    bytes32 public constant _TOKEN_PERMISSIONS_TYPEHASH = keccak256("TokenPermissions(address token,uint256 amount)");
                    bytes32 public constant _PERMIT_TRANSFER_FROM_TYPEHASH = keccak256(
                        "PermitTransferFrom(TokenPermissions permitted,address spender,uint256 nonce,uint256 deadline)TokenPermissions(address token,uint256 amount)"
                    );
                    bytes32 public constant _PERMIT_BATCH_TRANSFER_FROM_TYPEHASH = keccak256(
                        "PermitBatchTransferFrom(TokenPermissions[] permitted,address spender,uint256 nonce,uint256 deadline)TokenPermissions(address token,uint256 amount)"
                    );
                    string public constant _TOKEN_PERMISSIONS_TYPESTRING = "TokenPermissions(address token,uint256 amount)";
                    string public constant _PERMIT_TRANSFER_FROM_WITNESS_TYPEHASH_STUB =
                        "PermitWitnessTransferFrom(TokenPermissions permitted,address spender,uint256 nonce,uint256 deadline,";
                    string public constant _PERMIT_BATCH_WITNESS_TRANSFER_FROM_TYPEHASH_STUB =
                        "PermitBatchWitnessTransferFrom(TokenPermissions[] permitted,address spender,uint256 nonce,uint256 deadline,";
                    function hash(IAllowanceTransfer.PermitSingle memory permitSingle) internal pure returns (bytes32) {
                        bytes32 permitHash = _hashPermitDetails(permitSingle.details);
                        return
                            keccak256(abi.encode(_PERMIT_SINGLE_TYPEHASH, permitHash, permitSingle.spender, permitSingle.sigDeadline));
                    }
                    function hash(IAllowanceTransfer.PermitBatch memory permitBatch) internal pure returns (bytes32) {
                        uint256 numPermits = permitBatch.details.length;
                        bytes32[] memory permitHashes = new bytes32[](numPermits);
                        for (uint256 i = 0; i < numPermits; ++i) {
                            permitHashes[i] = _hashPermitDetails(permitBatch.details[i]);
                        }
                        return keccak256(
                            abi.encode(
                                _PERMIT_BATCH_TYPEHASH,
                                keccak256(abi.encodePacked(permitHashes)),
                                permitBatch.spender,
                                permitBatch.sigDeadline
                            )
                        );
                    }
                    function hash(ISignatureTransfer.PermitTransferFrom memory permit) internal view returns (bytes32) {
                        bytes32 tokenPermissionsHash = _hashTokenPermissions(permit.permitted);
                        return keccak256(
                            abi.encode(_PERMIT_TRANSFER_FROM_TYPEHASH, tokenPermissionsHash, msg.sender, permit.nonce, permit.deadline)
                        );
                    }
                    function hash(ISignatureTransfer.PermitBatchTransferFrom memory permit) internal view returns (bytes32) {
                        uint256 numPermitted = permit.permitted.length;
                        bytes32[] memory tokenPermissionHashes = new bytes32[](numPermitted);
                        for (uint256 i = 0; i < numPermitted; ++i) {
                            tokenPermissionHashes[i] = _hashTokenPermissions(permit.permitted[i]);
                        }
                        return keccak256(
                            abi.encode(
                                _PERMIT_BATCH_TRANSFER_FROM_TYPEHASH,
                                keccak256(abi.encodePacked(tokenPermissionHashes)),
                                msg.sender,
                                permit.nonce,
                                permit.deadline
                            )
                        );
                    }
                    function hashWithWitness(
                        ISignatureTransfer.PermitTransferFrom memory permit,
                        bytes32 witness,
                        string calldata witnessTypeString
                    ) internal view returns (bytes32) {
                        bytes32 typeHash = keccak256(abi.encodePacked(_PERMIT_TRANSFER_FROM_WITNESS_TYPEHASH_STUB, witnessTypeString));
                        bytes32 tokenPermissionsHash = _hashTokenPermissions(permit.permitted);
                        return keccak256(abi.encode(typeHash, tokenPermissionsHash, msg.sender, permit.nonce, permit.deadline, witness));
                    }
                    function hashWithWitness(
                        ISignatureTransfer.PermitBatchTransferFrom memory permit,
                        bytes32 witness,
                        string calldata witnessTypeString
                    ) internal view returns (bytes32) {
                        bytes32 typeHash =
                            keccak256(abi.encodePacked(_PERMIT_BATCH_WITNESS_TRANSFER_FROM_TYPEHASH_STUB, witnessTypeString));
                        uint256 numPermitted = permit.permitted.length;
                        bytes32[] memory tokenPermissionHashes = new bytes32[](numPermitted);
                        for (uint256 i = 0; i < numPermitted; ++i) {
                            tokenPermissionHashes[i] = _hashTokenPermissions(permit.permitted[i]);
                        }
                        return keccak256(
                            abi.encode(
                                typeHash,
                                keccak256(abi.encodePacked(tokenPermissionHashes)),
                                msg.sender,
                                permit.nonce,
                                permit.deadline,
                                witness
                            )
                        );
                    }
                    function _hashPermitDetails(IAllowanceTransfer.PermitDetails memory details) private pure returns (bytes32) {
                        return keccak256(abi.encode(_PERMIT_DETAILS_TYPEHASH, details));
                    }
                    function _hashTokenPermissions(ISignatureTransfer.TokenPermissions memory permitted)
                        private
                        pure
                        returns (bytes32)
                    {
                        return keccak256(abi.encode(_TOKEN_PERMISSIONS_TYPEHASH, permitted));
                    }
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.17;
                import {IERC1271} from "../interfaces/IERC1271.sol";
                library SignatureVerification {
                    /// @notice Thrown when the passed in signature is not a valid length
                    error InvalidSignatureLength();
                    /// @notice Thrown when the recovered signer is equal to the zero address
                    error InvalidSignature();
                    /// @notice Thrown when the recovered signer does not equal the claimedSigner
                    error InvalidSigner();
                    /// @notice Thrown when the recovered contract signature is incorrect
                    error InvalidContractSignature();
                    bytes32 constant UPPER_BIT_MASK = (0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
                    function verify(bytes calldata signature, bytes32 hash, address claimedSigner) internal view {
                        bytes32 r;
                        bytes32 s;
                        uint8 v;
                        if (claimedSigner.code.length == 0) {
                            if (signature.length == 65) {
                                (r, s) = abi.decode(signature, (bytes32, bytes32));
                                v = uint8(signature[64]);
                            } else if (signature.length == 64) {
                                // EIP-2098
                                bytes32 vs;
                                (r, vs) = abi.decode(signature, (bytes32, bytes32));
                                s = vs & UPPER_BIT_MASK;
                                v = uint8(uint256(vs >> 255)) + 27;
                            } else {
                                revert InvalidSignatureLength();
                            }
                            address signer = ecrecover(hash, v, r, s);
                            if (signer == address(0)) revert InvalidSignature();
                            if (signer != claimedSigner) revert InvalidSigner();
                        } else {
                            bytes4 magicValue = IERC1271(claimedSigner).isValidSignature(hash, signature);
                            if (magicValue != IERC1271.isValidSignature.selector) revert InvalidContractSignature();
                        }
                    }
                }
                

                File 7 of 7: FeeCollector
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.0;
                import {Owned} from "solmate/auth/Owned.sol";
                import {ERC20} from "solmate/tokens/ERC20.sol";
                import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
                import {IFeeCollector} from "./interfaces/IFeeCollector.sol";
                import {IPermit2} from "./external/IPermit2.sol";
                /// @notice The collector of protocol fees that will be used to swap and send to a fee recipient address.
                contract FeeCollector is Owned, IFeeCollector {
                    using SafeTransferLib for ERC20;
                    address public universalRouter;
                    ERC20 public immutable feeToken;
                    IPermit2 public immutable permit2;
                    uint256 public constant MAX_APPROVAL_AMOUNT = type(uint256).max;
                    uint160 public constant MAX_PERMIT2_APPROVAL_AMOUNT = type(uint160).max;
                    uint48 public constant MAX_PERMIT2_DEADLINE = type(uint48).max;
                    constructor(address _owner, address _universalRouter, address _permit2, address _feeToken) Owned(_owner) {
                        universalRouter = _universalRouter;
                        feeToken = ERC20(_feeToken);
                        permit2 = IPermit2(_permit2);
                    }
                    /// @inheritdoc IFeeCollector
                    function swapBalance(bytes calldata swapData, uint256 nativeValue) external onlyOwner {
                        _execute(swapData, nativeValue);
                    }
                    /// @inheritdoc IFeeCollector
                    function swapBalance(bytes calldata swapData, uint256 nativeValue, ERC20[] calldata tokensToApprove)
                        external
                        onlyOwner
                    {
                        unchecked {
                            for (uint256 i = 0; i < tokensToApprove.length; i++) {
                                tokensToApprove[i].safeApprove(address(permit2), MAX_APPROVAL_AMOUNT);
                                permit2.approve(
                                    address(tokensToApprove[i]), universalRouter, MAX_PERMIT2_APPROVAL_AMOUNT, MAX_PERMIT2_DEADLINE
                                );
                            }
                        }
                        _execute(swapData, nativeValue);
                    }
                    /// @notice Helper function to call UniversalRouter.
                    /// @param swapData The bytes call data to be forwarded to UniversalRouter.
                    /// @param nativeValue The amount of native currency to send to UniversalRouter.
                    function _execute(bytes calldata swapData, uint256 nativeValue) internal {
                        (bool success,) = universalRouter.call{value: nativeValue}(swapData);
                        if (!success) revert UniversalRouterCallFailed();
                    }
                    /// @inheritdoc IFeeCollector
                    function revokeTokenApprovals(ERC20[] calldata tokensToRevoke) external onlyOwner {
                        unchecked {
                            for (uint256 i = 0; i < tokensToRevoke.length; i++) {
                                tokensToRevoke[i].safeApprove(address(permit2), 0);
                            }
                        }
                    }
                    /// @inheritdoc IFeeCollector
                    function revokePermit2Approvals(IPermit2.TokenSpenderPair[] calldata approvals) external onlyOwner {
                        permit2.lockdown(approvals);
                    }
                    /// @inheritdoc IFeeCollector
                    function withdrawFeeToken(address feeRecipient, uint256 amount) external onlyOwner {
                        feeToken.safeTransfer(feeRecipient, amount);
                    }
                    /// @inheritdoc IFeeCollector
                    function setUniversalRouter(address _universalRouter) external onlyOwner {
                        emit UniversalRouterChanged(universalRouter, _universalRouter);
                        universalRouter = _universalRouter;
                    }
                    receive() external payable {}
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Simple single owner authorization mixin.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/auth/Owned.sol)
                abstract contract Owned {
                    /*//////////////////////////////////////////////////////////////
                                                 EVENTS
                    //////////////////////////////////////////////////////////////*/
                    event OwnershipTransferred(address indexed user, address indexed newOwner);
                    /*//////////////////////////////////////////////////////////////
                                            OWNERSHIP STORAGE
                    //////////////////////////////////////////////////////////////*/
                    address public owner;
                    modifier onlyOwner() virtual {
                        require(msg.sender == owner, "UNAUTHORIZED");
                        _;
                    }
                    /*//////////////////////////////////////////////////////////////
                                               CONSTRUCTOR
                    //////////////////////////////////////////////////////////////*/
                    constructor(address _owner) {
                        owner = _owner;
                        emit OwnershipTransferred(address(0), _owner);
                    }
                    /*//////////////////////////////////////////////////////////////
                                             OWNERSHIP LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function transferOwnership(address newOwner) public virtual onlyOwner {
                        owner = newOwner;
                        emit OwnershipTransferred(msg.sender, newOwner);
                    }
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                /// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
                /// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
                /// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
                abstract contract ERC20 {
                    /*//////////////////////////////////////////////////////////////
                                                 EVENTS
                    //////////////////////////////////////////////////////////////*/
                    event Transfer(address indexed from, address indexed to, uint256 amount);
                    event Approval(address indexed owner, address indexed spender, uint256 amount);
                    /*//////////////////////////////////////////////////////////////
                                            METADATA STORAGE
                    //////////////////////////////////////////////////////////////*/
                    string public name;
                    string public symbol;
                    uint8 public immutable decimals;
                    /*//////////////////////////////////////////////////////////////
                                              ERC20 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 public totalSupply;
                    mapping(address => uint256) public balanceOf;
                    mapping(address => mapping(address => uint256)) public allowance;
                    /*//////////////////////////////////////////////////////////////
                                            EIP-2612 STORAGE
                    //////////////////////////////////////////////////////////////*/
                    uint256 internal immutable INITIAL_CHAIN_ID;
                    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
                    mapping(address => uint256) public nonces;
                    /*//////////////////////////////////////////////////////////////
                                               CONSTRUCTOR
                    //////////////////////////////////////////////////////////////*/
                    constructor(
                        string memory _name,
                        string memory _symbol,
                        uint8 _decimals
                    ) {
                        name = _name;
                        symbol = _symbol;
                        decimals = _decimals;
                        INITIAL_CHAIN_ID = block.chainid;
                        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
                    }
                    /*//////////////////////////////////////////////////////////////
                                               ERC20 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function approve(address spender, uint256 amount) public virtual returns (bool) {
                        allowance[msg.sender][spender] = amount;
                        emit Approval(msg.sender, spender, amount);
                        return true;
                    }
                    function transfer(address to, uint256 amount) public virtual returns (bool) {
                        balanceOf[msg.sender] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(msg.sender, to, amount);
                        return true;
                    }
                    function transferFrom(
                        address from,
                        address to,
                        uint256 amount
                    ) public virtual returns (bool) {
                        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
                        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
                        balanceOf[from] -= amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(from, to, amount);
                        return true;
                    }
                    /*//////////////////////////////////////////////////////////////
                                             EIP-2612 LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function permit(
                        address owner,
                        address spender,
                        uint256 value,
                        uint256 deadline,
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    ) public virtual {
                        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
                        // Unchecked because the only math done is incrementing
                        // the owner's nonce which cannot realistically overflow.
                        unchecked {
                            address recoveredAddress = ecrecover(
                                keccak256(
                                    abi.encodePacked(
                                        "\\x19\\x01",
                                        DOMAIN_SEPARATOR(),
                                        keccak256(
                                            abi.encode(
                                                keccak256(
                                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                                ),
                                                owner,
                                                spender,
                                                value,
                                                nonces[owner]++,
                                                deadline
                                            )
                                        )
                                    )
                                ),
                                v,
                                r,
                                s
                            );
                            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
                            allowance[recoveredAddress][spender] = value;
                        }
                        emit Approval(owner, spender, value);
                    }
                    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
                        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
                    }
                    function computeDomainSeparator() internal view virtual returns (bytes32) {
                        return
                            keccak256(
                                abi.encode(
                                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                                    keccak256(bytes(name)),
                                    keccak256("1"),
                                    block.chainid,
                                    address(this)
                                )
                            );
                    }
                    /*//////////////////////////////////////////////////////////////
                                        INTERNAL MINT/BURN LOGIC
                    //////////////////////////////////////////////////////////////*/
                    function _mint(address to, uint256 amount) internal virtual {
                        totalSupply += amount;
                        // Cannot overflow because the sum of all user
                        // balances can't exceed the max uint256 value.
                        unchecked {
                            balanceOf[to] += amount;
                        }
                        emit Transfer(address(0), to, amount);
                    }
                    function _burn(address from, uint256 amount) internal virtual {
                        balanceOf[from] -= amount;
                        // Cannot underflow because a user's balance
                        // will never be larger than the total supply.
                        unchecked {
                            totalSupply -= amount;
                        }
                        emit Transfer(from, address(0), amount);
                    }
                }
                // SPDX-License-Identifier: AGPL-3.0-only
                pragma solidity >=0.8.0;
                import {ERC20} from "../tokens/ERC20.sol";
                /// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
                /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
                /// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
                /// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
                library SafeTransferLib {
                    /*//////////////////////////////////////////////////////////////
                                             ETH OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferETH(address to, uint256 amount) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Transfer the ETH and store if it succeeded or not.
                            success := call(gas(), to, amount, 0, 0, 0, 0)
                        }
                        require(success, "ETH_TRANSFER_FAILED");
                    }
                    /*//////////////////////////////////////////////////////////////
                                            ERC20 OPERATIONS
                    //////////////////////////////////////////////////////////////*/
                    function safeTransferFrom(
                        ERC20 token,
                        address from,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "from" argument.
                            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FROM_FAILED");
                    }
                    function safeTransfer(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "TRANSFER_FAILED");
                    }
                    function safeApprove(
                        ERC20 token,
                        address to,
                        uint256 amount
                    ) internal {
                        bool success;
                        /// @solidity memory-safe-assembly
                        assembly {
                            // Get a pointer to some free memory.
                            let freeMemoryPointer := mload(0x40)
                            // Write the abi-encoded calldata into memory, beginning with the function selector.
                            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
                            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
                            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
                            success := and(
                                // Set success to whether the call reverted, if not we check it either
                                // returned exactly 1 (can't just be non-zero data), or had no return data.
                                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                                // Counterintuitively, this call must be positioned second to the or() call in the
                                // surrounding and() call or else returndatasize() will be zero during the computation.
                                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
                            )
                        }
                        require(success, "APPROVE_FAILED");
                    }
                }
                // SPDX-License-Identifier: GPL-2.0-or-later
                pragma solidity ^0.8.13;
                import {ERC20} from "solmate/tokens/ERC20.sol";
                import {IPermit2} from "../external/IPermit2.sol";
                /// @notice The collector of protocol fees that will be used to swap and send to a fee recipient address.
                interface IFeeCollector {
                    /// @notice Error thrown when the call to UniversalRouter fails.
                    error UniversalRouterCallFailed();
                    /// @notice Emitted when the UniversalRouter address is changed.
                    /// @param oldUniversalRouter The old router address.
                    /// @param newUniversalRouter The new router address.
                    event UniversalRouterChanged(address oldUniversalRouter, address newUniversalRouter);
                    /// @notice Swaps the contract balance.
                    /// @param swapData The bytes call data to be forwarded to UniversalRouter.
                    /// @param nativeValue The amount of native currency to send to UniversalRouter.
                    function swapBalance(bytes calldata swapData, uint256 nativeValue) external;
                    /// @notice Approves tokens for swapping and then swaps the contract balance.
                    /// @param swapData The bytes call data to be forwarded to UniversalRouter.
                    /// @param nativeValue The amount of native currency to send to UniversalRouter.
                    /// @param tokensToApprove An array of ERC20 tokens to approve for spending.
                    function swapBalance(bytes calldata swapData, uint256 nativeValue, ERC20[] calldata tokensToApprove) external;
                    /// @notice Revokes approvals on tokens by setting their allowance to 0.
                    /// @param tokensToRevoke The token to revoke the approval for.
                    function revokeTokenApprovals(ERC20[] calldata tokensToRevoke) external;
                    /// @notice Revokes the permit2 allowance of a spender by setting token allowances to 0.
                    /// @param approvals The approvals to revoke.
                    function revokePermit2Approvals(IPermit2.TokenSpenderPair[] calldata approvals) external;
                    /// @notice Transfers the fee token balance from this contract to the fee recipient.
                    /// @param feeRecipient The address to send the fee token balance to.
                    /// @param amount The amount to withdraw.
                    function withdrawFeeToken(address feeRecipient, uint256 amount) external;
                    /// @notice Sets the address of the UniversalRouter contract.
                    /// @param _universalRouter The address of the UniversalRouter contract.
                    function setUniversalRouter(address _universalRouter) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.0;
                import {IAllowanceTransfer} from "./IAllowanceTransfer.sol";
                /// @notice Permit2 handles signature-based transfers in SignatureTransfer and allowance-based transfers in AllowanceTransfer.
                /// @dev Users must approve Permit2 before calling any of the transfer functions.
                interface IPermit2 is IAllowanceTransfer {
                // IPermit2 unifies the two interfaces so users have maximal flexibility with their approval.
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.0;
                import {IEIP712} from "./IEIP712.sol";
                /// @title AllowanceTransfer
                /// @notice Handles ERC20 token permissions through signature based allowance setting and ERC20 token transfers by checking allowed amounts
                /// @dev Requires user's token approval on the Permit2 contract
                interface IAllowanceTransfer is IEIP712 {
                    /// @notice A token spender pair.
                    struct TokenSpenderPair {
                        // the token the spender is approved
                        address token;
                        // the spender address
                        address spender;
                    }
                    /// @notice A mapping from owner address to token address to spender address to PackedAllowance struct, which contains details and conditions of the approval.
                    /// @notice The mapping is indexed in the above order see: allowance[ownerAddress][tokenAddress][spenderAddress]
                    /// @dev The packed slot holds the allowed amount, expiration at which the allowed amount is no longer valid, and current nonce thats updated on any signature based approvals.
                    function allowance(address user, address token, address spender)
                        external
                        view
                        returns (uint160 amount, uint48 expiration, uint48 nonce);
                    /// @notice Approves the spender to use up to amount of the specified token up until the expiration
                    /// @param token The token to approve
                    /// @param spender The spender address to approve
                    /// @param amount The approved amount of the token
                    /// @param expiration The timestamp at which the approval is no longer valid
                    /// @dev The packed allowance also holds a nonce, which will stay unchanged in approve
                    /// @dev Setting amount to type(uint160).max sets an unlimited approval
                    function approve(address token, address spender, uint160 amount, uint48 expiration) external;
                    /// @notice Enables performing a "lockdown" of the sender's Permit2 identity
                    /// by batch revoking approvals
                    /// @param approvals Array of approvals to revoke.
                    function lockdown(TokenSpenderPair[] calldata approvals) external;
                }
                // SPDX-License-Identifier: MIT
                pragma solidity ^0.8.0;
                interface IEIP712 {
                    function DOMAIN_SEPARATOR() external view returns (bytes32);
                }