ETH Price: $2,133.55 (+4.61%)

Transaction Decoder

Block:
17070984 at Apr-18-2023 03:41:23 AM +UTC
Transaction Fee:
0.009379924221034512 ETH $20.01
Gas Used:
263,478 Gas / 35.600407704 Gwei

Emitted Events:

224 RoyaltiesSplitter.PaymentReceived( from=[Receiver] 0x000000000000ad05ccc4f10045630fb830b95127, amount=7440000000000000 )
225 IronPawGang.Transfer( from=0xd577df616cbfda9c7d322e8cb5938cd9a47b837e, to=[Sender] 0x1f9021fc36f9a92d4414ef330b2a3f6a9e83382e, tokenId=3599 )
226 0x000000000000ad05ccc4f10045630fb830b95127.0x61cbb2a3dee0b6064c2e681aadd61677fb4ef319f0b547508d495626f5a62f64( 0x61cbb2a3dee0b6064c2e681aadd61677fb4ef319f0b547508d495626f5a62f64, 0x000000000000000000000000d577df616cbfda9c7d322e8cb5938cd9a47b837e, 0x0000000000000000000000001f9021fc36f9a92d4414ef330b2a3f6a9e83382e, 0000000000000000000000000000000000000000000000000000000000000080, 2e58b09d06a26b97ad94ae6207ea5e16e7db3e13ce62ddacbdb226bca26e9d08, 00000000000000000000000000000000000000000000000000000000000002c0, 1db5ce9264095d9f0504a6022ea299dbe6b50ea613540f195663311649d83a2b, 000000000000000000000000d577df616cbfda9c7d322e8cb5938cd9a47b837e, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000dab4a563819e8fd93dba3b25bc3495, 000000000000000000000000b283dbacecd75594b66039a341a48db2d85fa37a, 0000000000000000000000000000000000000000000000000000000000000e0f, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000210a4cfc6940000, 00000000000000000000000000000000000000000000000000000000643dd818, 0000000000000000000000000000000000000000000000000000000064471298, 00000000000000000000000000000000000000000000000000000000000001a0, 000000000000000000000000000000006f0703fc4e7a90932f0ea6f4747435ce, 0000000000000000000000000000000000000000000000000000000000000200, 0000000000000000000000000000000000000000000000000000000000000001, 00000000000000000000000000000000000000000000000000000000000001f4, 0000000000000000000000004c78656faea93b5305c69064b5c40fae62c9ba73, 0000000000000000000000000000000000000000000000000000000000000001, 0100000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000001f9021fc36f9a92d4414ef330b2a3f6a9e83382e, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000dab4a563819e8fd93dba3b25bc3495, 000000000000000000000000b283dbacecd75594b66039a341a48db2d85fa37a, 0000000000000000000000000000000000000000000000000000000000000e0f, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000210a4cfc6940000, 00000000000000000000000000000000000000000000000000000000643dd819, 00000000000000000000000000000000000000000000000000000000643e1f61, 00000000000000000000000000000000000000000000000000000000000001a0, 00000000000000000000000000000000a0f8a3ea4c923b18af82ad842d9747a7, 00000000000000000000000000000000000000000000000000000000000001c0, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000001, 0100000000000000000000000000000000000000000000000000000000000000 )

Account State Difference:

  Address   Before After State Difference Code
0x00000000...830B95127
(Blur.io: Marketplace)
0x1f9021fc...a9E83382e
0.181426498306772048 Eth
Nonce: 7
0.023246574085737536 Eth
Nonce: 8
0.158179924221034512
0x4C78656f...e62C9Ba73 0.086663900000000065 Eth0.094103900000000065 Eth0.00744
0xB283dBac...2d85fa37a
0xd577df61...9a47b837e 0.123257142187112356 Eth0.264617142187112356 Eth0.14136
(Fee Recipient: 0xeBe...Acf)
13,736.53183023927985765 Eth13,736.53185658707985765 Eth0.0000263478

Execution Trace

ETH 0.1488 Blur.io: Marketplace.9a1fc3a7( )
  • ETH 0.1488 BlurExchange.execute( sell=[{name:order, type:tuple, order:1, indexed:false, value:[{name:trader, type:address, order:1, indexed:false, value:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e, valueString:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e}, {name:side, type:uint8, order:2, indexed:false, value:1, valueString:1}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774616, valueString:1681774616}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1682379416, valueString:1682379416}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:147580734447149172687240285902626633166, valueString:147580734447149172687240285902626633166}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}], valueString:[{name:trader, type:address, order:1, indexed:false, value:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e, valueString:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e}, {name:side, type:uint8, order:2, indexed:false, value:1, valueString:1}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774616, valueString:1681774616}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1682379416, valueString:1682379416}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:147580734447149172687240285902626633166, valueString:147580734447149172687240285902626633166}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}]}, {name:v, type:uint8, order:2, indexed:false, value:27, valueString:27}, {name:r, type:bytes32, order:3, indexed:false, value:A083E420121D5427BE24B1B5E556F878F0B9F9D6D4E90803E3465C1A4498FE60, valueString:A083E420121D5427BE24B1B5E556F878F0B9F9D6D4E90803E3465C1A4498FE60}, {name:s, type:bytes32, order:4, indexed:false, value:319052D827C6F1982866277A99594036B4A2188EEF408660F902AA13F696BD7E, valueString:319052D827C6F1982866277A99594036B4A2188EEF408660F902AA13F696BD7E}, {name:extraSignature, type:bytes, order:5, indexed:false, value:0x000000000000000000000000000000000000000000000000000000000000001C2EFEAEC05376779A90A56E1D2021FB7CE40C72F461B0DAD0B890DC562A106B9E54D771D4BD10B276698CE7435F2957844B3CE5A6CFFFFFE03A34216584C7132F, valueString:0x000000000000000000000000000000000000000000000000000000000000001C2EFEAEC05376779A90A56E1D2021FB7CE40C72F461B0DAD0B890DC562A106B9E54D771D4BD10B276698CE7435F2957844B3CE5A6CFFFFFE03A34216584C7132F}, {name:signatureVersion, type:uint8, order:6, indexed:false, value:0, valueString:0}, {name:blockNumber, type:uint256, order:7, indexed:false, value:17070982, valueString:17070982}], buy=[{name:order, type:tuple, order:1, indexed:false, value:[{name:trader, type:address, order:1, indexed:false, value:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e, valueString:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e}, {name:side, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774617, valueString:1681774617}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1681792865, valueString:1681792865}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:213967493542356243467695962673254975399, valueString:213967493542356243467695962673254975399}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}], valueString:[{name:trader, type:address, order:1, indexed:false, value:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e, valueString:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e}, {name:side, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774617, valueString:1681774617}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1681792865, valueString:1681792865}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:213967493542356243467695962673254975399, valueString:213967493542356243467695962673254975399}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}]}, {name:v, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:r, type:bytes32, order:3, indexed:false, value:0000000000000000000000000000000000000000000000000000000000000000, valueString:0000000000000000000000000000000000000000000000000000000000000000}, {name:s, type:bytes32, order:4, indexed:false, value:0000000000000000000000000000000000000000000000000000000000000000, valueString:0000000000000000000000000000000000000000000000000000000000000000}, {name:extraSignature, type:bytes, order:5, indexed:false, value:0x000000000000000000000000000000000000000000000000000000000000001CB78C56EF5E366D2EBDA0FA7B1B11F5D8ED9DACA5F1B4132EBE46F5282BF40FA943DE010E5F98248017830F6815448F055A9AFB88E03B987C07DD23640A821F86, valueString:0x000000000000000000000000000000000000000000000000000000000000001CB78C56EF5E366D2EBDA0FA7B1B11F5D8ED9DACA5F1B4132EBE46F5282BF40FA943DE010E5F98248017830F6815448F055A9AFB88E03B987C07DD23640A821F86}, {name:signatureVersion, type:uint8, order:6, indexed:false, value:0, valueString:0}, {name:blockNumber, type:uint256, order:7, indexed:false, value:17070982, valueString:17070982}] )
    • Null: 0x000...001.a8d240e0( )
    • Null: 0x000...001.e28cdaa3( )
    • Null: 0x000...001.0c495193( )
    • 0x3a35a3102b5c6bd1e4d3237248be071ef53c8331.874516cd( )
    • StandardPolicyERC721.canMatchMakerAsk( makerAsk=[{name:trader, type:address, order:1, indexed:false, value:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e, valueString:0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e}, {name:side, type:uint8, order:2, indexed:false, value:1, valueString:1}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774616, valueString:1681774616}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1682379416, valueString:1682379416}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:147580734447149172687240285902626633166, valueString:147580734447149172687240285902626633166}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}], takerBid=[{name:trader, type:address, order:1, indexed:false, value:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e, valueString:0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e}, {name:side, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:matchingPolicy, type:address, order:3, indexed:false, value:0x0000000000daB4A563819e8fd93dbA3b25BC3495, valueString:0x0000000000daB4A563819e8fd93dbA3b25BC3495}, {name:collection, type:address, order:4, indexed:false, value:0xB283dBacecD75594b66039a341A48DB2d85fa37a, valueString:0xB283dBacecD75594b66039a341A48DB2d85fa37a}, {name:tokenId, type:uint256, order:5, indexed:false, value:3599, valueString:3599}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:paymentToken, type:address, order:7, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:price, type:uint256, order:8, indexed:false, value:148800000000000000, valueString:148800000000000000}, {name:listingTime, type:uint256, order:9, indexed:false, value:1681774617, valueString:1681774617}, {name:expirationTime, type:uint256, order:10, indexed:false, value:1681792865, valueString:1681792865}, {name:fees, type:tuple[], order:11, indexed:false}, {name:salt, type:uint256, order:12, indexed:false, value:213967493542356243467695962673254975399, valueString:213967493542356243467695962673254975399}, {name:extraParams, type:bytes, order:13, indexed:false, value:0x01, valueString:0x01}] ) => ( True, 148800000000000000, 3599, 1, 0 )
    • ETH 0.00744 RoyaltiesSplitter.CALL( )
    • ETH 0.14136 0xd577df616cbfda9c7d322e8cb5938cd9a47b837e.CALL( )
    • Blur: Execution Delegate.789f93f6( )
      • IronPawGang.safeTransferFrom( from=0xd577df616cbfdA9C7d322E8cb5938CD9a47b837e, to=0x1f9021fc36F9A92D4414ef330b2A3F6a9E83382e, tokenId=3599 )
        • OperatorFilterRegistry.isOperatorAllowed( registrant=0xB283dBacecD75594b66039a341A48DB2d85fa37a, operator=0x00000000000111AbE46ff893f3B2fdF1F759a8A8 ) => ( True )
        • OperatorFilterRegistry.isOperatorAllowed( registrant=0xB283dBacecD75594b66039a341A48DB2d85fa37a, operator=0x00000000000111AbE46ff893f3B2fdF1F759a8A8 ) => ( True )
        • OperatorFilterRegistry.isOperatorAllowed( registrant=0xB283dBacecD75594b66039a341A48DB2d85fa37a, operator=0x00000000000111AbE46ff893f3B2fdF1F759a8A8 ) => ( True )
          File 1 of 5: RoyaltiesSplitter
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.9;
          /*
                  ████████████
                ██            ██
              ██              ██▓▓
              ██            ████▓▓▓▓▓▓
              ██      ██████▓▓▒▒▓▓▓▓▓▓▓▓
              ████████▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▒▒
              ██    ████████▓▓▒▒▒▒▒▒▒▒▒▒
              ██            ██▓▓▒▒▒▒▒▒▒▒
              ██              ██▓▓▓▓▓▓▓▓
              ██    ██      ██    ██       '||''|.                    ||           '||
              ██                  ██        ||   ||  ... ..   ....   ...  .. ...    || ...    ...   ... ... ...
                ██              ██          ||'''|.   ||' '' '' .||   ||   ||  ||   ||'  || .|  '|.  ||  ||  |
                  ██          ██            ||    ||  ||     .|' ||   ||   ||  ||   ||    | ||   ||   ||| |||
                    ██████████             .||...|'  .||.    '|..'|' .||. .||. ||.  '|...'   '|..|'    |   |
          */
          import "@openzeppelin/contracts/utils/Address.sol";
          import "@openzeppelin/contracts/utils/Context.sol";
          import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
          import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
          import "@openzeppelin/contracts/access/AccessControl.sol";
          /**
           * @title UpdatableSplitter
           * @dev This contract is similar to a common PaymentSplitter except it trades the ability
           * to pay each payee individually for the option to update its payees and their splits.
           */
          contract UpdatableSplitter is Context, AccessControl {
              event PayeeAdded(address account, uint256 shares);
              event EtherFlushed(uint256 amount);
              event TokenFlushed(IERC20 indexed token, uint256 amount);
              event PaymentReceived(address from, uint256 amount);
              bytes32 public constant FLUSHWORTHY = keccak256("FLUSHWORTHY");
              uint256 private _totalShares;
              address[] private _payees;
              mapping(address => uint256) private _shares;
              address[] private _commonTokens;
              /**
               * @dev Takes a list of payees and a corresponding list of shares.
               *
               * All addresses in `payees` must be non-zero. Both arrays must have the same non-zero length, and there must be no duplicates in `payees`.
               *
               * Additionally takes a list of ERC20 token addresses that can be flushed with `flushCommon`.
               */
              constructor(address[] memory payees, uint256[] memory shares_, address[] memory tokenAddresses) payable {
                  _grantRole(DEFAULT_ADMIN_ROLE, _msgSender());
                  _grantRole(FLUSHWORTHY, _msgSender());
                  for (uint256 i = 0; i < payees.length; i++) {
                      _grantRole(FLUSHWORTHY, payees[i]);
                  }
                  updateSplit(payees, shares_);
                  _commonTokens = tokenAddresses;
              }
              receive() external payable virtual {
                  emit PaymentReceived(_msgSender(), msg.value);
              }
              /**
               * @dev Getter for the total shares held by payees.
               */
              function totalShares() public view returns (uint256) {
                  return _totalShares;
              }
              /**
               * @dev Getter for the address of an individual payee.
               */
              function payee(uint256 index) public view returns (address) {
                  return _payees[index];
              }
              /**
               * @dev Getter for the assigned number of shares for a given payee.
               */
              function shares(address payee_) public view returns (uint256) {
                  return _shares[payee_];
              }
              /**
               * @dev Function to add ERC20 token addresses to the list of common tokens.
               */
              function addToken(address tokenAddress) public onlyRole(DEFAULT_ADMIN_ROLE) {
                  require(tokenAddress != address(0), "UpdatableSplitter: address is the zero address");
                  _commonTokens.push(tokenAddress);
              }
              /**
               * @dev Updates the list of payees and their corresponding shares. Requires both lists to be same length.
               *
               * Flushes all holdings before updating.
               */
              function updateSplit(address[] memory payees, uint256[] memory shares_) public onlyRole(DEFAULT_ADMIN_ROLE) {
                  require(payees.length == shares_.length, "UpdatableSplitter: payees and shares length mismatch");
                  require(payees.length > 0, "UpdatableSplitter: no payees");
                  flushCommon();
                  _clear();
                  for (uint256 i = 0; i < payees.length; i++) {
                      _addPayee(payees[i], shares_[i]);
                  }
              }
              /**
               * @dev Flushes all Ether held by contract, split according to the shares.
               */
              function flush() public onlyRole(FLUSHWORTHY) {
                  (uint256 unit, uint256 balance) = _unitAndBalance();
                  if (unit == 0 || balance == 0) return;
                  for (uint256 i = 0; i < _payees.length; i++) {
                      address payee_ = payee(i);
                      uint256 split = shares(payee_) * unit;
                      Address.sendValue(payable(payee_), split);
                  }
                  emit EtherFlushed(balance);
              }
              /**
               * @dev Flushes total balance of given ERC20 token, split according to the shares.
               */
              function flushToken(IERC20 token) public onlyRole(FLUSHWORTHY) {
                  (uint256 unit, uint256 balance) = _unitAndBalance(token);
                  if (unit == 0 || balance == 0) return;
                  for (uint256 i = 0; i < _payees.length; i++) {
                      address payee_ = payee(i);
                      uint256 split = shares(payee_) * unit;
                      SafeERC20.safeTransfer(token, payee_, split);
                  }
                  emit TokenFlushed(token, balance);
              }
              /**
               * @dev Flushes all Ether + all registered common tokens, split according to the shares.
               */
              function flushCommon() public onlyRole(FLUSHWORTHY) {
                  flush();
                  for (uint256 i = 0; i < _commonTokens.length; i++) {
                      flushToken(IERC20(_commonTokens[i]));
                  }
              }
              function _clear() private {
                  for (uint256 i = 0; i < _payees.length; i++) {
                      _shares[payee(i)] = 0;
                  }
                  delete _payees;
                  _totalShares = 0;
              }
              function _addPayee(address account, uint256 shares_) private {
                  require(account != address(0), "UpdatableSplitter: account is the zero address");
                  require(shares_ > 0, "UpdatableSplitter: shares are 0");
                  require(shares(account) == 0, "UpdatableSplitter: account already has shares");
                  _payees.push(account);
                  _shares[account] = shares_;
                  _totalShares = _totalShares + shares_;
                  emit PayeeAdded(account, shares_);
              }
              function _unitAndBalance() private view returns (uint256, uint256 balance) {
                  balance = uint256(address(this).balance);
                  if (_totalShares == 0 || balance == 0) return (0, 0);
                  return (balance / _totalShares, balance);
              }
              function _unitAndBalance(IERC20 token) private view returns (uint256, uint256 balance) {
                  balance = token.balanceOf(address(this));
                  if (_totalShares == 0 || balance == 0) return (0, 0);
                  return (balance / _totalShares, balance);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (access/AccessControl.sol)
          pragma solidity ^0.8.0;
          import "./IAccessControl.sol";
          import "../utils/Context.sol";
          import "../utils/Strings.sol";
          import "../utils/introspection/ERC165.sol";
          /**
           * @dev Contract module that allows children to implement role-based access
           * control mechanisms. This is a lightweight version that doesn't allow enumerating role
           * members except through off-chain means by accessing the contract event logs. Some
           * applications may benefit from on-chain enumerability, for those cases see
           * {AccessControlEnumerable}.
           *
           * Roles are referred to by their `bytes32` identifier. These should be exposed
           * in the external API and be unique. The best way to achieve this is by
           * using `public constant` hash digests:
           *
           * ```
           * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
           * ```
           *
           * Roles can be used to represent a set of permissions. To restrict access to a
           * function call, use {hasRole}:
           *
           * ```
           * function foo() public {
           *     require(hasRole(MY_ROLE, msg.sender));
           *     ...
           * }
           * ```
           *
           * Roles can be granted and revoked dynamically via the {grantRole} and
           * {revokeRole} functions. Each role has an associated admin role, and only
           * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
           *
           * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
           * that only accounts with this role will be able to grant or revoke other
           * roles. More complex role relationships can be created by using
           * {_setRoleAdmin}.
           *
           * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
           * grant and revoke this role. Extra precautions should be taken to secure
           * accounts that have been granted it.
           */
          abstract contract AccessControl is Context, IAccessControl, ERC165 {
              struct RoleData {
                  mapping(address => bool) members;
                  bytes32 adminRole;
              }
              mapping(bytes32 => RoleData) private _roles;
              bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
              /**
               * @dev Modifier that checks that an account has a specific role. Reverts
               * with a standardized message including the required role.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               *
               * _Available since v4.1._
               */
              modifier onlyRole(bytes32 role) {
                  _checkRole(role);
                  _;
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
              }
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
                  return _roles[role].members[account];
              }
              /**
               * @dev Revert with a standard message if `_msgSender()` is missing `role`.
               * Overriding this function changes the behavior of the {onlyRole} modifier.
               *
               * Format of the revert message is described in {_checkRole}.
               *
               * _Available since v4.6._
               */
              function _checkRole(bytes32 role) internal view virtual {
                  _checkRole(role, _msgSender());
              }
              /**
               * @dev Revert with a standard message if `account` is missing `role`.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               */
              function _checkRole(bytes32 role, address account) internal view virtual {
                  if (!hasRole(role, account)) {
                      revert(
                          string(
                              abi.encodePacked(
                                  "AccessControl: account ",
                                  Strings.toHexString(account),
                                  " is missing role ",
                                  Strings.toHexString(uint256(role), 32)
                              )
                          )
                      );
                  }
              }
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
                  return _roles[role].adminRole;
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleGranted} event.
               */
              function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _grantRole(role, account);
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleRevoked} event.
               */
              function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _revokeRole(role, account);
              }
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been revoked `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               *
               * May emit a {RoleRevoked} event.
               */
              function renounceRole(bytes32 role, address account) public virtual override {
                  require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                  _revokeRole(role, account);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event. Note that unlike {grantRole}, this function doesn't perform any
               * checks on the calling account.
               *
               * May emit a {RoleGranted} event.
               *
               * [WARNING]
               * ====
               * This function should only be called from the constructor when setting
               * up the initial roles for the system.
               *
               * Using this function in any other way is effectively circumventing the admin
               * system imposed by {AccessControl}.
               * ====
               *
               * NOTE: This function is deprecated in favor of {_grantRole}.
               */
              function _setupRole(bytes32 role, address account) internal virtual {
                  _grantRole(role, account);
              }
              /**
               * @dev Sets `adminRole` as ``role``'s admin role.
               *
               * Emits a {RoleAdminChanged} event.
               */
              function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                  bytes32 previousAdminRole = getRoleAdmin(role);
                  _roles[role].adminRole = adminRole;
                  emit RoleAdminChanged(role, previousAdminRole, adminRole);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleGranted} event.
               */
              function _grantRole(bytes32 role, address account) internal virtual {
                  if (!hasRole(role, account)) {
                      _roles[role].members[account] = true;
                      emit RoleGranted(role, account, _msgSender());
                  }
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleRevoked} event.
               */
              function _revokeRole(bytes32 role, address account) internal virtual {
                  if (hasRole(role, account)) {
                      _roles[role].members[account] = false;
                      emit RoleRevoked(role, account, _msgSender());
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev External interface of AccessControl declared to support ERC165 detection.
           */
          interface IAccessControl {
              /**
               * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
               *
               * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
               * {RoleAdminChanged} not being emitted signaling this.
               *
               * _Available since v3.1._
               */
              event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
              /**
               * @dev Emitted when `account` is granted `role`.
               *
               * `sender` is the account that originated the contract call, an admin role
               * bearer except when using {AccessControl-_setupRole}.
               */
              event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Emitted when `account` is revoked `role`.
               *
               * `sender` is the account that originated the contract call:
               *   - if using `revokeRole`, it is the admin role bearer
               *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
               */
              event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) external view returns (bool);
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {AccessControl-_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) external view returns (bytes32);
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function grantRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function revokeRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been granted `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               */
              function renounceRole(bytes32 role, address account) external;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC20 standard as defined in the EIP.
           */
          interface IERC20 {
              /**
               * @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);
              /**
               * @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 `to`.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transfer(address to, 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 `from` to `to` 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 from,
                  address to,
                  uint256 amount
              ) external returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
          pragma solidity ^0.8.0;
          /**
           * @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: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol)
          pragma solidity ^0.8.0;
          import "../IERC20.sol";
          import "../extensions/draft-IERC20Permit.sol";
          import "../../../utils/Address.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 {
              using Address for address;
              function safeTransfer(
                  IERC20 token,
                  address to,
                  uint256 value
              ) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
              }
              function safeTransferFrom(
                  IERC20 token,
                  address from,
                  address to,
                  uint256 value
              ) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
              }
              /**
               * @dev Deprecated. This function has issues similar to the ones found in
               * {IERC20-approve}, and its usage is discouraged.
               *
               * Whenever possible, use {safeIncreaseAllowance} and
               * {safeDecreaseAllowance} instead.
               */
              function safeApprove(
                  IERC20 token,
                  address spender,
                  uint256 value
              ) internal {
                  // safeApprove should only be called when setting an initial allowance,
                  // or when resetting it to zero. To increase and decrease it, use
                  // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                  require(
                      (value == 0) || (token.allowance(address(this), spender) == 0),
                      "SafeERC20: approve from non-zero to non-zero allowance"
                  );
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
              }
              function safeIncreaseAllowance(
                  IERC20 token,
                  address spender,
                  uint256 value
              ) internal {
                  uint256 newAllowance = token.allowance(address(this), spender) + value;
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
              }
              function safeDecreaseAllowance(
                  IERC20 token,
                  address spender,
                  uint256 value
              ) internal {
                  unchecked {
                      uint256 oldAllowance = token.allowance(address(this), spender);
                      require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                      uint256 newAllowance = oldAllowance - value;
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                  }
              }
              function safePermit(
                  IERC20Permit token,
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  uint256 nonceBefore = token.nonces(owner);
                  token.permit(owner, spender, value, deadline, v, r, s);
                  uint256 nonceAfter = token.nonces(owner);
                  require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
              }
              /**
               * @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).
               * @param token The token targeted by the call.
               * @param data The call data (encoded using abi.encode or one of its variants).
               */
              function _callOptionalReturn(IERC20 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. We use {Address-functionCall} to perform this call, which verifies that
                  // the target address contains contract code and also asserts for success in the low-level call.
                  bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                  if (returndata.length > 0) {
                      // Return data is optional
                      require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
          pragma solidity ^0.8.1;
          /**
           * @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
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
                  return account.code.length > 0;
              }
              /**
               * @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, "Address: insufficient balance");
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @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:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @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) {
                  return functionDelegateCall(target, data, "Address: low-level delegate call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
               * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
               *
               * _Available since v4.8._
               */
              function verifyCallResultFromTarget(
                  address target,
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  if (success) {
                      if (returndata.length == 0) {
                          // only check isContract if the call was successful and the return data is empty
                          // otherwise we already know that it was a contract
                          require(isContract(target), "Address: call to non-contract");
                      }
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              /**
               * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason or using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal pure returns (bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              function _revert(bytes memory returndata, string memory errorMessage) private pure {
                  // 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
                      /// @solidity memory-safe-assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)
          pragma solidity ^0.8.0;
          import "./math/Math.sol";
          /**
           * @dev String operations.
           */
          library Strings {
              bytes16 private constant _SYMBOLS = "0123456789abcdef";
              uint8 private constant _ADDRESS_LENGTH = 20;
              /**
               * @dev Converts a `uint256` to its ASCII `string` decimal representation.
               */
              function toString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      uint256 length = Math.log10(value) + 1;
                      string memory buffer = new string(length);
                      uint256 ptr;
                      /// @solidity memory-safe-assembly
                      assembly {
                          ptr := add(buffer, add(32, length))
                      }
                      while (true) {
                          ptr--;
                          /// @solidity memory-safe-assembly
                          assembly {
                              mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                          }
                          value /= 10;
                          if (value == 0) break;
                      }
                      return buffer;
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
               */
              function toHexString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      return toHexString(value, Math.log256(value) + 1);
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
               */
              function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                  bytes memory buffer = new bytes(2 * length + 2);
                  buffer[0] = "0";
                  buffer[1] = "x";
                  for (uint256 i = 2 * length + 1; i > 1; --i) {
                      buffer[i] = _SYMBOLS[value & 0xf];
                      value >>= 4;
                  }
                  require(value == 0, "Strings: hex length insufficient");
                  return string(buffer);
              }
              /**
               * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
               */
              function toHexString(address addr) internal pure returns (string memory) {
                  return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
          pragma solidity ^0.8.0;
          import "./IERC165.sol";
          /**
           * @dev Implementation of the {IERC165} interface.
           *
           * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
           * for the additional interface id that will be supported. For example:
           *
           * ```solidity
           * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
           *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
           * }
           * ```
           *
           * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
           */
          abstract contract ERC165 is IERC165 {
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IERC165).interfaceId;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC165 standard, as defined in the
           * https://eips.ethereum.org/EIPS/eip-165[EIP].
           *
           * Implementers can declare support of contract interfaces, which can then be
           * queried by others ({ERC165Checker}).
           *
           * For an implementation, see {ERC165}.
           */
          interface IERC165 {
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30 000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Standard math utilities missing in the Solidity language.
           */
          library Math {
              enum Rounding {
                  Down, // Toward negative infinity
                  Up, // Toward infinity
                  Zero // Toward zero
              }
              /**
               * @dev Returns the largest of two numbers.
               */
              function max(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a > b ? a : b;
              }
              /**
               * @dev Returns the smallest of two numbers.
               */
              function min(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a < b ? a : b;
              }
              /**
               * @dev Returns the average of two numbers. The result is rounded towards
               * zero.
               */
              function average(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b) / 2 can overflow.
                  return (a & b) + (a ^ b) / 2;
              }
              /**
               * @dev Returns the ceiling of the division of two numbers.
               *
               * This differs from standard division with `/` in that it rounds up instead
               * of rounding down.
               */
              function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b - 1) / b can overflow on addition, so we distribute.
                  return a == 0 ? 0 : (a - 1) / b + 1;
              }
              /**
               * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
               * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
               * with further edits by Uniswap Labs also under MIT license.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator
              ) internal pure returns (uint256 result) {
                  unchecked {
                      // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                      // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                      // variables such that product = prod1 * 2^256 + prod0.
                      uint256 prod0; // Least significant 256 bits of the product
                      uint256 prod1; // Most significant 256 bits of the product
                      assembly {
                          let mm := mulmod(x, y, not(0))
                          prod0 := mul(x, y)
                          prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                      }
                      // Handle non-overflow cases, 256 by 256 division.
                      if (prod1 == 0) {
                          return prod0 / denominator;
                      }
                      // Make sure the result is less than 2^256. Also prevents denominator == 0.
                      require(denominator > prod1);
                      ///////////////////////////////////////////////
                      // 512 by 256 division.
                      ///////////////////////////////////////////////
                      // Make division exact by subtracting the remainder from [prod1 prod0].
                      uint256 remainder;
                      assembly {
                          // Compute remainder using mulmod.
                          remainder := mulmod(x, y, denominator)
                          // Subtract 256 bit number from 512 bit number.
                          prod1 := sub(prod1, gt(remainder, prod0))
                          prod0 := sub(prod0, remainder)
                      }
                      // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                      // See https://cs.stackexchange.com/q/138556/92363.
                      // Does not overflow because the denominator cannot be zero at this stage in the function.
                      uint256 twos = denominator & (~denominator + 1);
                      assembly {
                          // Divide denominator by twos.
                          denominator := div(denominator, twos)
                          // Divide [prod1 prod0] by twos.
                          prod0 := div(prod0, twos)
                          // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                          twos := add(div(sub(0, twos), twos), 1)
                      }
                      // Shift in bits from prod1 into prod0.
                      prod0 |= prod1 * twos;
                      // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                      // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                      // four bits. That is, denominator * inv = 1 mod 2^4.
                      uint256 inverse = (3 * denominator) ^ 2;
                      // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                      // in modular arithmetic, doubling the correct bits in each step.
                      inverse *= 2 - denominator * inverse; // inverse mod 2^8
                      inverse *= 2 - denominator * inverse; // inverse mod 2^16
                      inverse *= 2 - denominator * inverse; // inverse mod 2^32
                      inverse *= 2 - denominator * inverse; // inverse mod 2^64
                      inverse *= 2 - denominator * inverse; // inverse mod 2^128
                      inverse *= 2 - denominator * inverse; // inverse mod 2^256
                      // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                      // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                      // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                      // is no longer required.
                      result = prod0 * inverse;
                      return result;
                  }
              }
              /**
               * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator,
                  Rounding rounding
              ) internal pure returns (uint256) {
                  uint256 result = mulDiv(x, y, denominator);
                  if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                      result += 1;
                  }
                  return result;
              }
              /**
               * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
               *
               * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
               */
              function sqrt(uint256 a) internal pure returns (uint256) {
                  if (a == 0) {
                      return 0;
                  }
                  // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                  //
                  // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                  // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
                  //
                  // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
                  // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
                  // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
                  //
                  // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
                  uint256 result = 1 << (log2(a) >> 1);
                  // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                  // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                  // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                  // into the expected uint128 result.
                  unchecked {
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      return min(result, a / result);
                  }
              }
              /**
               * @notice Calculates sqrt(a), following the selected rounding direction.
               */
              function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = sqrt(a);
                      return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 2, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 128;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 64;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 32;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 16;
                      }
                      if (value >> 8 > 0) {
                          value >>= 8;
                          result += 8;
                      }
                      if (value >> 4 > 0) {
                          value >>= 4;
                          result += 4;
                      }
                      if (value >> 2 > 0) {
                          value >>= 2;
                          result += 2;
                      }
                      if (value >> 1 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log2(value);
                      return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 10, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >= 10**64) {
                          value /= 10**64;
                          result += 64;
                      }
                      if (value >= 10**32) {
                          value /= 10**32;
                          result += 32;
                      }
                      if (value >= 10**16) {
                          value /= 10**16;
                          result += 16;
                      }
                      if (value >= 10**8) {
                          value /= 10**8;
                          result += 8;
                      }
                      if (value >= 10**4) {
                          value /= 10**4;
                          result += 4;
                      }
                      if (value >= 10**2) {
                          value /= 10**2;
                          result += 2;
                      }
                      if (value >= 10**1) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log10(value);
                      return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 256, rounded down, of a positive value.
               * Returns 0 if given 0.
               *
               * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
               */
              function log256(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 16;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 8;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 4;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 2;
                      }
                      if (value >> 8 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log256(value);
                      return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.9;
          /**
           *    8 888888888o.      ,o888888o.        ,o888888o.
           *    8 8888    `88.    8888     `88.     8888     `88.
           *    8 8888     `88 ,8 8888       `8. ,8 8888       `8.
           *    8 8888     ,88 88 8888           88 8888
           *    8 8888.   ,88' 88 8888           88 8888
           *    8 888888888P'  88 8888           88 8888
           *    8 8888`8b      88 8888           88 8888
           *    8 8888 `8b.    `8 8888       .8' `8 8888       .8'
           *    8 8888   `8b.     8888     ,88'     8888     ,88'
           *    8 8888     `88.    `8888888P'        `8888888P'
           */
          import "brnbw/UpdatableSplitter.sol";
          contract RoyaltiesSplitter is UpdatableSplitter {
              constructor(address[] memory payees, uint256[] memory shares, address[] memory tokens)
                  UpdatableSplitter(payees, shares, tokens)
              {}
          }
          

          File 2 of 5: IronPawGang
          // SPDX-License-Identifier: MIT
          // ERC721A Contracts v4.2.3
          // Creator: Chiru Labs
          pragma solidity ^0.8.4;
          import './IERC721A.sol';
          /**
           * @dev Interface of ERC721 token receiver.
           */
          interface ERC721A__IERC721Receiver {
              function onERC721Received(
                  address operator,
                  address from,
                  uint256 tokenId,
                  bytes calldata data
              ) external returns (bytes4);
          }
          /**
           * @title ERC721A
           *
           * @dev Implementation of the [ERC721](https://eips.ethereum.org/EIPS/eip-721)
           * Non-Fungible Token Standard, including the Metadata extension.
           * Optimized for lower gas during batch mints.
           *
           * Token IDs are minted in sequential order (e.g. 0, 1, 2, 3, ...)
           * starting from `_startTokenId()`.
           *
           * Assumptions:
           *
           * - An owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
           * - The maximum token ID cannot exceed 2**256 - 1 (max value of uint256).
           */
          contract ERC721A is IERC721A {
              // Bypass for a `--via-ir` bug (https://github.com/chiru-labs/ERC721A/pull/364).
              struct TokenApprovalRef {
                  address value;
              }
              // =============================================================
              //                           CONSTANTS
              // =============================================================
              // Mask of an entry in packed address data.
              uint256 private constant _BITMASK_ADDRESS_DATA_ENTRY = (1 << 64) - 1;
              // The bit position of `numberMinted` in packed address data.
              uint256 private constant _BITPOS_NUMBER_MINTED = 64;
              // The bit position of `numberBurned` in packed address data.
              uint256 private constant _BITPOS_NUMBER_BURNED = 128;
              // The bit position of `aux` in packed address data.
              uint256 private constant _BITPOS_AUX = 192;
              // Mask of all 256 bits in packed address data except the 64 bits for `aux`.
              uint256 private constant _BITMASK_AUX_COMPLEMENT = (1 << 192) - 1;
              // The bit position of `startTimestamp` in packed ownership.
              uint256 private constant _BITPOS_START_TIMESTAMP = 160;
              // The bit mask of the `burned` bit in packed ownership.
              uint256 private constant _BITMASK_BURNED = 1 << 224;
              // The bit position of the `nextInitialized` bit in packed ownership.
              uint256 private constant _BITPOS_NEXT_INITIALIZED = 225;
              // The bit mask of the `nextInitialized` bit in packed ownership.
              uint256 private constant _BITMASK_NEXT_INITIALIZED = 1 << 225;
              // The bit position of `extraData` in packed ownership.
              uint256 private constant _BITPOS_EXTRA_DATA = 232;
              // Mask of all 256 bits in a packed ownership except the 24 bits for `extraData`.
              uint256 private constant _BITMASK_EXTRA_DATA_COMPLEMENT = (1 << 232) - 1;
              // The mask of the lower 160 bits for addresses.
              uint256 private constant _BITMASK_ADDRESS = (1 << 160) - 1;
              // The maximum `quantity` that can be minted with {_mintERC2309}.
              // This limit is to prevent overflows on the address data entries.
              // For a limit of 5000, a total of 3.689e15 calls to {_mintERC2309}
              // is required to cause an overflow, which is unrealistic.
              uint256 private constant _MAX_MINT_ERC2309_QUANTITY_LIMIT = 5000;
              // The `Transfer` event signature is given by:
              // `keccak256(bytes("Transfer(address,address,uint256)"))`.
              bytes32 private constant _TRANSFER_EVENT_SIGNATURE =
                  0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;
              // =============================================================
              //                            STORAGE
              // =============================================================
              // The next token ID to be minted.
              uint256 private _currentIndex;
              // The number of tokens burned.
              uint256 private _burnCounter;
              // Token name
              string private _name;
              // Token symbol
              string private _symbol;
              // Mapping from token ID to ownership details
              // An empty struct value does not necessarily mean the token is unowned.
              // See {_packedOwnershipOf} implementation for details.
              //
              // Bits Layout:
              // - [0..159]   `addr`
              // - [160..223] `startTimestamp`
              // - [224]      `burned`
              // - [225]      `nextInitialized`
              // - [232..255] `extraData`
              mapping(uint256 => uint256) private _packedOwnerships;
              // Mapping owner address to address data.
              //
              // Bits Layout:
              // - [0..63]    `balance`
              // - [64..127]  `numberMinted`
              // - [128..191] `numberBurned`
              // - [192..255] `aux`
              mapping(address => uint256) private _packedAddressData;
              // Mapping from token ID to approved address.
              mapping(uint256 => TokenApprovalRef) private _tokenApprovals;
              // Mapping from owner to operator approvals
              mapping(address => mapping(address => bool)) private _operatorApprovals;
              // =============================================================
              //                          CONSTRUCTOR
              // =============================================================
              constructor(string memory name_, string memory symbol_) {
                  _name = name_;
                  _symbol = symbol_;
                  _currentIndex = _startTokenId();
              }
              // =============================================================
              //                   TOKEN COUNTING OPERATIONS
              // =============================================================
              /**
               * @dev Returns the starting token ID.
               * To change the starting token ID, please override this function.
               */
              function _startTokenId() internal view virtual returns (uint256) {
                  return 0;
              }
              /**
               * @dev Returns the next token ID to be minted.
               */
              function _nextTokenId() internal view virtual returns (uint256) {
                  return _currentIndex;
              }
              /**
               * @dev Returns the total number of tokens in existence.
               * Burned tokens will reduce the count.
               * To get the total number of tokens minted, please see {_totalMinted}.
               */
              function totalSupply() public view virtual override returns (uint256) {
                  // Counter underflow is impossible as _burnCounter cannot be incremented
                  // more than `_currentIndex - _startTokenId()` times.
                  unchecked {
                      return _currentIndex - _burnCounter - _startTokenId();
                  }
              }
              /**
               * @dev Returns the total amount of tokens minted in the contract.
               */
              function _totalMinted() internal view virtual returns (uint256) {
                  // Counter underflow is impossible as `_currentIndex` does not decrement,
                  // and it is initialized to `_startTokenId()`.
                  unchecked {
                      return _currentIndex - _startTokenId();
                  }
              }
              /**
               * @dev Returns the total number of tokens burned.
               */
              function _totalBurned() internal view virtual returns (uint256) {
                  return _burnCounter;
              }
              // =============================================================
              //                    ADDRESS DATA OPERATIONS
              // =============================================================
              /**
               * @dev Returns the number of tokens in `owner`'s account.
               */
              function balanceOf(address owner) public view virtual override returns (uint256) {
                  if (owner == address(0)) revert BalanceQueryForZeroAddress();
                  return _packedAddressData[owner] & _BITMASK_ADDRESS_DATA_ENTRY;
              }
              /**
               * Returns the number of tokens minted by `owner`.
               */
              function _numberMinted(address owner) internal view returns (uint256) {
                  return (_packedAddressData[owner] >> _BITPOS_NUMBER_MINTED) & _BITMASK_ADDRESS_DATA_ENTRY;
              }
              /**
               * Returns the number of tokens burned by or on behalf of `owner`.
               */
              function _numberBurned(address owner) internal view returns (uint256) {
                  return (_packedAddressData[owner] >> _BITPOS_NUMBER_BURNED) & _BITMASK_ADDRESS_DATA_ENTRY;
              }
              /**
               * Returns the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
               */
              function _getAux(address owner) internal view returns (uint64) {
                  return uint64(_packedAddressData[owner] >> _BITPOS_AUX);
              }
              /**
               * Sets the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
               * If there are multiple variables, please pack them into a uint64.
               */
              function _setAux(address owner, uint64 aux) internal virtual {
                  uint256 packed = _packedAddressData[owner];
                  uint256 auxCasted;
                  // Cast `aux` with assembly to avoid redundant masking.
                  assembly {
                      auxCasted := aux
                  }
                  packed = (packed & _BITMASK_AUX_COMPLEMENT) | (auxCasted << _BITPOS_AUX);
                  _packedAddressData[owner] = packed;
              }
              // =============================================================
              //                            IERC165
              // =============================================================
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30000 gas.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  // The interface IDs are constants representing the first 4 bytes
                  // of the XOR of all function selectors in the interface.
                  // See: [ERC165](https://eips.ethereum.org/EIPS/eip-165)
                  // (e.g. `bytes4(i.functionA.selector ^ i.functionB.selector ^ ...)`)
                  return
                      interfaceId == 0x01ffc9a7 || // ERC165 interface ID for ERC165.
                      interfaceId == 0x80ac58cd || // ERC165 interface ID for ERC721.
                      interfaceId == 0x5b5e139f; // ERC165 interface ID for ERC721Metadata.
              }
              // =============================================================
              //                        IERC721Metadata
              // =============================================================
              /**
               * @dev Returns the token collection name.
               */
              function name() public view virtual override returns (string memory) {
                  return _name;
              }
              /**
               * @dev Returns the token collection symbol.
               */
              function symbol() public view virtual override returns (string memory) {
                  return _symbol;
              }
              /**
               * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
               */
              function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
                  if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
                  string memory baseURI = _baseURI();
                  return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, _toString(tokenId))) : '';
              }
              /**
               * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
               * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
               * by default, it can be overridden in child contracts.
               */
              function _baseURI() internal view virtual returns (string memory) {
                  return '';
              }
              // =============================================================
              //                     OWNERSHIPS OPERATIONS
              // =============================================================
              /**
               * @dev Returns the owner of the `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function ownerOf(uint256 tokenId) public view virtual override returns (address) {
                  return address(uint160(_packedOwnershipOf(tokenId)));
              }
              /**
               * @dev Gas spent here starts off proportional to the maximum mint batch size.
               * It gradually moves to O(1) as tokens get transferred around over time.
               */
              function _ownershipOf(uint256 tokenId) internal view virtual returns (TokenOwnership memory) {
                  return _unpackedOwnership(_packedOwnershipOf(tokenId));
              }
              /**
               * @dev Returns the unpacked `TokenOwnership` struct at `index`.
               */
              function _ownershipAt(uint256 index) internal view virtual returns (TokenOwnership memory) {
                  return _unpackedOwnership(_packedOwnerships[index]);
              }
              /**
               * @dev Initializes the ownership slot minted at `index` for efficiency purposes.
               */
              function _initializeOwnershipAt(uint256 index) internal virtual {
                  if (_packedOwnerships[index] == 0) {
                      _packedOwnerships[index] = _packedOwnershipOf(index);
                  }
              }
              /**
               * Returns the packed ownership data of `tokenId`.
               */
              function _packedOwnershipOf(uint256 tokenId) private view returns (uint256) {
                  uint256 curr = tokenId;
                  unchecked {
                      if (_startTokenId() <= curr)
                          if (curr < _currentIndex) {
                              uint256 packed = _packedOwnerships[curr];
                              // If not burned.
                              if (packed & _BITMASK_BURNED == 0) {
                                  // Invariant:
                                  // There will always be an initialized ownership slot
                                  // (i.e. `ownership.addr != address(0) && ownership.burned == false`)
                                  // before an unintialized ownership slot
                                  // (i.e. `ownership.addr == address(0) && ownership.burned == false`)
                                  // Hence, `curr` will not underflow.
                                  //
                                  // We can directly compare the packed value.
                                  // If the address is zero, packed will be zero.
                                  while (packed == 0) {
                                      packed = _packedOwnerships[--curr];
                                  }
                                  return packed;
                              }
                          }
                  }
                  revert OwnerQueryForNonexistentToken();
              }
              /**
               * @dev Returns the unpacked `TokenOwnership` struct from `packed`.
               */
              function _unpackedOwnership(uint256 packed) private pure returns (TokenOwnership memory ownership) {
                  ownership.addr = address(uint160(packed));
                  ownership.startTimestamp = uint64(packed >> _BITPOS_START_TIMESTAMP);
                  ownership.burned = packed & _BITMASK_BURNED != 0;
                  ownership.extraData = uint24(packed >> _BITPOS_EXTRA_DATA);
              }
              /**
               * @dev Packs ownership data into a single uint256.
               */
              function _packOwnershipData(address owner, uint256 flags) private view returns (uint256 result) {
                  assembly {
                      // Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
                      owner := and(owner, _BITMASK_ADDRESS)
                      // `owner | (block.timestamp << _BITPOS_START_TIMESTAMP) | flags`.
                      result := or(owner, or(shl(_BITPOS_START_TIMESTAMP, timestamp()), flags))
                  }
              }
              /**
               * @dev Returns the `nextInitialized` flag set if `quantity` equals 1.
               */
              function _nextInitializedFlag(uint256 quantity) private pure returns (uint256 result) {
                  // For branchless setting of the `nextInitialized` flag.
                  assembly {
                      // `(quantity == 1) << _BITPOS_NEXT_INITIALIZED`.
                      result := shl(_BITPOS_NEXT_INITIALIZED, eq(quantity, 1))
                  }
              }
              // =============================================================
              //                      APPROVAL OPERATIONS
              // =============================================================
              /**
               * @dev Gives permission to `to` to transfer `tokenId` token to another account.
               * The approval is cleared when the token is transferred.
               *
               * Only a single account can be approved at a time, so approving the
               * zero address clears previous approvals.
               *
               * Requirements:
               *
               * - The caller must own the token or be an approved operator.
               * - `tokenId` must exist.
               *
               * Emits an {Approval} event.
               */
              function approve(address to, uint256 tokenId) public payable virtual override {
                  address owner = ownerOf(tokenId);
                  if (_msgSenderERC721A() != owner)
                      if (!isApprovedForAll(owner, _msgSenderERC721A())) {
                          revert ApprovalCallerNotOwnerNorApproved();
                      }
                  _tokenApprovals[tokenId].value = to;
                  emit Approval(owner, to, tokenId);
              }
              /**
               * @dev Returns the account approved for `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function getApproved(uint256 tokenId) public view virtual override returns (address) {
                  if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
                  return _tokenApprovals[tokenId].value;
              }
              /**
               * @dev Approve or remove `operator` as an operator for the caller.
               * Operators can call {transferFrom} or {safeTransferFrom}
               * for any token owned by the caller.
               *
               * Requirements:
               *
               * - The `operator` cannot be the caller.
               *
               * Emits an {ApprovalForAll} event.
               */
              function setApprovalForAll(address operator, bool approved) public virtual override {
                  _operatorApprovals[_msgSenderERC721A()][operator] = approved;
                  emit ApprovalForAll(_msgSenderERC721A(), operator, approved);
              }
              /**
               * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
               *
               * See {setApprovalForAll}.
               */
              function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
                  return _operatorApprovals[owner][operator];
              }
              /**
               * @dev Returns whether `tokenId` exists.
               *
               * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
               *
               * Tokens start existing when they are minted. See {_mint}.
               */
              function _exists(uint256 tokenId) internal view virtual returns (bool) {
                  return
                      _startTokenId() <= tokenId &&
                      tokenId < _currentIndex && // If within bounds,
                      _packedOwnerships[tokenId] & _BITMASK_BURNED == 0; // and not burned.
              }
              /**
               * @dev Returns whether `msgSender` is equal to `approvedAddress` or `owner`.
               */
              function _isSenderApprovedOrOwner(
                  address approvedAddress,
                  address owner,
                  address msgSender
              ) private pure returns (bool result) {
                  assembly {
                      // Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
                      owner := and(owner, _BITMASK_ADDRESS)
                      // Mask `msgSender` to the lower 160 bits, in case the upper bits somehow aren't clean.
                      msgSender := and(msgSender, _BITMASK_ADDRESS)
                      // `msgSender == owner || msgSender == approvedAddress`.
                      result := or(eq(msgSender, owner), eq(msgSender, approvedAddress))
                  }
              }
              /**
               * @dev Returns the storage slot and value for the approved address of `tokenId`.
               */
              function _getApprovedSlotAndAddress(uint256 tokenId)
                  private
                  view
                  returns (uint256 approvedAddressSlot, address approvedAddress)
              {
                  TokenApprovalRef storage tokenApproval = _tokenApprovals[tokenId];
                  // The following is equivalent to `approvedAddress = _tokenApprovals[tokenId].value`.
                  assembly {
                      approvedAddressSlot := tokenApproval.slot
                      approvedAddress := sload(approvedAddressSlot)
                  }
              }
              // =============================================================
              //                      TRANSFER OPERATIONS
              // =============================================================
              /**
               * @dev Transfers `tokenId` from `from` to `to`.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must be owned by `from`.
               * - If the caller is not `from`, it must be approved to move this token
               * by either {approve} or {setApprovalForAll}.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) public payable virtual override {
                  uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
                  if (address(uint160(prevOwnershipPacked)) != from) revert TransferFromIncorrectOwner();
                  (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);
                  // The nested ifs save around 20+ gas over a compound boolean condition.
                  if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
                      if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
                  if (to == address(0)) revert TransferToZeroAddress();
                  _beforeTokenTransfers(from, to, tokenId, 1);
                  // Clear approvals from the previous owner.
                  assembly {
                      if approvedAddress {
                          // This is equivalent to `delete _tokenApprovals[tokenId]`.
                          sstore(approvedAddressSlot, 0)
                      }
                  }
                  // Underflow of the sender's balance is impossible because we check for
                  // ownership above and the recipient's balance can't realistically overflow.
                  // Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
                  unchecked {
                      // We can directly increment and decrement the balances.
                      --_packedAddressData[from]; // Updates: `balance -= 1`.
                      ++_packedAddressData[to]; // Updates: `balance += 1`.
                      // Updates:
                      // - `address` to the next owner.
                      // - `startTimestamp` to the timestamp of transfering.
                      // - `burned` to `false`.
                      // - `nextInitialized` to `true`.
                      _packedOwnerships[tokenId] = _packOwnershipData(
                          to,
                          _BITMASK_NEXT_INITIALIZED | _nextExtraData(from, to, prevOwnershipPacked)
                      );
                      // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
                      if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
                          uint256 nextTokenId = tokenId + 1;
                          // If the next slot's address is zero and not burned (i.e. packed value is zero).
                          if (_packedOwnerships[nextTokenId] == 0) {
                              // If the next slot is within bounds.
                              if (nextTokenId != _currentIndex) {
                                  // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                                  _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                              }
                          }
                      }
                  }
                  emit Transfer(from, to, tokenId);
                  _afterTokenTransfers(from, to, tokenId, 1);
              }
              /**
               * @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) public payable virtual override {
                  safeTransferFrom(from, to, tokenId, '');
              }
              /**
               * @dev Safely transfers `tokenId` token from `from` to `to`.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must exist and be owned by `from`.
               * - If the caller is not `from`, it must be approved to move this token
               * by either {approve} or {setApprovalForAll}.
               * - If `to` refers to a smart contract, it must implement
               * {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
               *
               * Emits a {Transfer} event.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes memory _data
              ) public payable virtual override {
                  transferFrom(from, to, tokenId);
                  if (to.code.length != 0)
                      if (!_checkContractOnERC721Received(from, to, tokenId, _data)) {
                          revert TransferToNonERC721ReceiverImplementer();
                      }
              }
              /**
               * @dev Hook that is called before a set of serially-ordered token IDs
               * are about to be transferred. This includes minting.
               * And also called before burning one token.
               *
               * `startTokenId` - the first token ID to be transferred.
               * `quantity` - the amount to be transferred.
               *
               * Calling conditions:
               *
               * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
               * transferred to `to`.
               * - When `from` is zero, `tokenId` will be minted for `to`.
               * - When `to` is zero, `tokenId` will be burned by `from`.
               * - `from` and `to` are never both zero.
               */
              function _beforeTokenTransfers(
                  address from,
                  address to,
                  uint256 startTokenId,
                  uint256 quantity
              ) internal virtual {}
              /**
               * @dev Hook that is called after a set of serially-ordered token IDs
               * have been transferred. This includes minting.
               * And also called after one token has been burned.
               *
               * `startTokenId` - the first token ID to be transferred.
               * `quantity` - the amount to be transferred.
               *
               * Calling conditions:
               *
               * - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
               * transferred to `to`.
               * - When `from` is zero, `tokenId` has been minted for `to`.
               * - When `to` is zero, `tokenId` has been burned by `from`.
               * - `from` and `to` are never both zero.
               */
              function _afterTokenTransfers(
                  address from,
                  address to,
                  uint256 startTokenId,
                  uint256 quantity
              ) internal virtual {}
              /**
               * @dev Private function to invoke {IERC721Receiver-onERC721Received} on a target contract.
               *
               * `from` - Previous owner of the given token ID.
               * `to` - Target address that will receive the token.
               * `tokenId` - Token ID to be transferred.
               * `_data` - Optional data to send along with the call.
               *
               * Returns whether the call correctly returned the expected magic value.
               */
              function _checkContractOnERC721Received(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes memory _data
              ) private returns (bool) {
                  try ERC721A__IERC721Receiver(to).onERC721Received(_msgSenderERC721A(), from, tokenId, _data) returns (
                      bytes4 retval
                  ) {
                      return retval == ERC721A__IERC721Receiver(to).onERC721Received.selector;
                  } catch (bytes memory reason) {
                      if (reason.length == 0) {
                          revert TransferToNonERC721ReceiverImplementer();
                      } else {
                          assembly {
                              revert(add(32, reason), mload(reason))
                          }
                      }
                  }
              }
              // =============================================================
              //                        MINT OPERATIONS
              // =============================================================
              /**
               * @dev Mints `quantity` tokens and transfers them to `to`.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - `quantity` must be greater than 0.
               *
               * Emits a {Transfer} event for each mint.
               */
              function _mint(address to, uint256 quantity) internal virtual {
                  uint256 startTokenId = _currentIndex;
                  if (quantity == 0) revert MintZeroQuantity();
                  _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                  // Overflows are incredibly unrealistic.
                  // `balance` and `numberMinted` have a maximum limit of 2**64.
                  // `tokenId` has a maximum limit of 2**256.
                  unchecked {
                      // Updates:
                      // - `balance += quantity`.
                      // - `numberMinted += quantity`.
                      //
                      // We can directly add to the `balance` and `numberMinted`.
                      _packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);
                      // Updates:
                      // - `address` to the owner.
                      // - `startTimestamp` to the timestamp of minting.
                      // - `burned` to `false`.
                      // - `nextInitialized` to `quantity == 1`.
                      _packedOwnerships[startTokenId] = _packOwnershipData(
                          to,
                          _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
                      );
                      uint256 toMasked;
                      uint256 end = startTokenId + quantity;
                      // Use assembly to loop and emit the `Transfer` event for gas savings.
                      // The duplicated `log4` removes an extra check and reduces stack juggling.
                      // The assembly, together with the surrounding Solidity code, have been
                      // delicately arranged to nudge the compiler into producing optimized opcodes.
                      assembly {
                          // Mask `to` to the lower 160 bits, in case the upper bits somehow aren't clean.
                          toMasked := and(to, _BITMASK_ADDRESS)
                          // Emit the `Transfer` event.
                          log4(
                              0, // Start of data (0, since no data).
                              0, // End of data (0, since no data).
                              _TRANSFER_EVENT_SIGNATURE, // Signature.
                              0, // `address(0)`.
                              toMasked, // `to`.
                              startTokenId // `tokenId`.
                          )
                          // The `iszero(eq(,))` check ensures that large values of `quantity`
                          // that overflows uint256 will make the loop run out of gas.
                          // The compiler will optimize the `iszero` away for performance.
                          for {
                              let tokenId := add(startTokenId, 1)
                          } iszero(eq(tokenId, end)) {
                              tokenId := add(tokenId, 1)
                          } {
                              // Emit the `Transfer` event. Similar to above.
                              log4(0, 0, _TRANSFER_EVENT_SIGNATURE, 0, toMasked, tokenId)
                          }
                      }
                      if (toMasked == 0) revert MintToZeroAddress();
                      _currentIndex = end;
                  }
                  _afterTokenTransfers(address(0), to, startTokenId, quantity);
              }
              /**
               * @dev Mints `quantity` tokens and transfers them to `to`.
               *
               * This function is intended for efficient minting only during contract creation.
               *
               * It emits only one {ConsecutiveTransfer} as defined in
               * [ERC2309](https://eips.ethereum.org/EIPS/eip-2309),
               * instead of a sequence of {Transfer} event(s).
               *
               * Calling this function outside of contract creation WILL make your contract
               * non-compliant with the ERC721 standard.
               * For full ERC721 compliance, substituting ERC721 {Transfer} event(s) with the ERC2309
               * {ConsecutiveTransfer} event is only permissible during contract creation.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - `quantity` must be greater than 0.
               *
               * Emits a {ConsecutiveTransfer} event.
               */
              function _mintERC2309(address to, uint256 quantity) internal virtual {
                  uint256 startTokenId = _currentIndex;
                  if (to == address(0)) revert MintToZeroAddress();
                  if (quantity == 0) revert MintZeroQuantity();
                  if (quantity > _MAX_MINT_ERC2309_QUANTITY_LIMIT) revert MintERC2309QuantityExceedsLimit();
                  _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                  // Overflows are unrealistic due to the above check for `quantity` to be below the limit.
                  unchecked {
                      // Updates:
                      // - `balance += quantity`.
                      // - `numberMinted += quantity`.
                      //
                      // We can directly add to the `balance` and `numberMinted`.
                      _packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);
                      // Updates:
                      // - `address` to the owner.
                      // - `startTimestamp` to the timestamp of minting.
                      // - `burned` to `false`.
                      // - `nextInitialized` to `quantity == 1`.
                      _packedOwnerships[startTokenId] = _packOwnershipData(
                          to,
                          _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
                      );
                      emit ConsecutiveTransfer(startTokenId, startTokenId + quantity - 1, address(0), to);
                      _currentIndex = startTokenId + quantity;
                  }
                  _afterTokenTransfers(address(0), to, startTokenId, quantity);
              }
              /**
               * @dev Safely mints `quantity` tokens and transfers them to `to`.
               *
               * Requirements:
               *
               * - If `to` refers to a smart contract, it must implement
               * {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
               * - `quantity` must be greater than 0.
               *
               * See {_mint}.
               *
               * Emits a {Transfer} event for each mint.
               */
              function _safeMint(
                  address to,
                  uint256 quantity,
                  bytes memory _data
              ) internal virtual {
                  _mint(to, quantity);
                  unchecked {
                      if (to.code.length != 0) {
                          uint256 end = _currentIndex;
                          uint256 index = end - quantity;
                          do {
                              if (!_checkContractOnERC721Received(address(0), to, index++, _data)) {
                                  revert TransferToNonERC721ReceiverImplementer();
                              }
                          } while (index < end);
                          // Reentrancy protection.
                          if (_currentIndex != end) revert();
                      }
                  }
              }
              /**
               * @dev Equivalent to `_safeMint(to, quantity, '')`.
               */
              function _safeMint(address to, uint256 quantity) internal virtual {
                  _safeMint(to, quantity, '');
              }
              // =============================================================
              //                        BURN OPERATIONS
              // =============================================================
              /**
               * @dev Equivalent to `_burn(tokenId, false)`.
               */
              function _burn(uint256 tokenId) internal virtual {
                  _burn(tokenId, false);
              }
              /**
               * @dev Destroys `tokenId`.
               * The approval is cleared when the token is burned.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               *
               * Emits a {Transfer} event.
               */
              function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
                  uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
                  address from = address(uint160(prevOwnershipPacked));
                  (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);
                  if (approvalCheck) {
                      // The nested ifs save around 20+ gas over a compound boolean condition.
                      if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
                          if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
                  }
                  _beforeTokenTransfers(from, address(0), tokenId, 1);
                  // Clear approvals from the previous owner.
                  assembly {
                      if approvedAddress {
                          // This is equivalent to `delete _tokenApprovals[tokenId]`.
                          sstore(approvedAddressSlot, 0)
                      }
                  }
                  // Underflow of the sender's balance is impossible because we check for
                  // ownership above and the recipient's balance can't realistically overflow.
                  // Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
                  unchecked {
                      // Updates:
                      // - `balance -= 1`.
                      // - `numberBurned += 1`.
                      //
                      // We can directly decrement the balance, and increment the number burned.
                      // This is equivalent to `packed -= 1; packed += 1 << _BITPOS_NUMBER_BURNED;`.
                      _packedAddressData[from] += (1 << _BITPOS_NUMBER_BURNED) - 1;
                      // Updates:
                      // - `address` to the last owner.
                      // - `startTimestamp` to the timestamp of burning.
                      // - `burned` to `true`.
                      // - `nextInitialized` to `true`.
                      _packedOwnerships[tokenId] = _packOwnershipData(
                          from,
                          (_BITMASK_BURNED | _BITMASK_NEXT_INITIALIZED) | _nextExtraData(from, address(0), prevOwnershipPacked)
                      );
                      // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
                      if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
                          uint256 nextTokenId = tokenId + 1;
                          // If the next slot's address is zero and not burned (i.e. packed value is zero).
                          if (_packedOwnerships[nextTokenId] == 0) {
                              // If the next slot is within bounds.
                              if (nextTokenId != _currentIndex) {
                                  // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                                  _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                              }
                          }
                      }
                  }
                  emit Transfer(from, address(0), tokenId);
                  _afterTokenTransfers(from, address(0), tokenId, 1);
                  // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
                  unchecked {
                      _burnCounter++;
                  }
              }
              // =============================================================
              //                     EXTRA DATA OPERATIONS
              // =============================================================
              /**
               * @dev Directly sets the extra data for the ownership data `index`.
               */
              function _setExtraDataAt(uint256 index, uint24 extraData) internal virtual {
                  uint256 packed = _packedOwnerships[index];
                  if (packed == 0) revert OwnershipNotInitializedForExtraData();
                  uint256 extraDataCasted;
                  // Cast `extraData` with assembly to avoid redundant masking.
                  assembly {
                      extraDataCasted := extraData
                  }
                  packed = (packed & _BITMASK_EXTRA_DATA_COMPLEMENT) | (extraDataCasted << _BITPOS_EXTRA_DATA);
                  _packedOwnerships[index] = packed;
              }
              /**
               * @dev Called during each token transfer to set the 24bit `extraData` field.
               * Intended to be overridden by the cosumer contract.
               *
               * `previousExtraData` - the value of `extraData` before transfer.
               *
               * Calling conditions:
               *
               * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
               * transferred to `to`.
               * - When `from` is zero, `tokenId` will be minted for `to`.
               * - When `to` is zero, `tokenId` will be burned by `from`.
               * - `from` and `to` are never both zero.
               */
              function _extraData(
                  address from,
                  address to,
                  uint24 previousExtraData
              ) internal view virtual returns (uint24) {}
              /**
               * @dev Returns the next extra data for the packed ownership data.
               * The returned result is shifted into position.
               */
              function _nextExtraData(
                  address from,
                  address to,
                  uint256 prevOwnershipPacked
              ) private view returns (uint256) {
                  uint24 extraData = uint24(prevOwnershipPacked >> _BITPOS_EXTRA_DATA);
                  return uint256(_extraData(from, to, extraData)) << _BITPOS_EXTRA_DATA;
              }
              // =============================================================
              //                       OTHER OPERATIONS
              // =============================================================
              /**
               * @dev Returns the message sender (defaults to `msg.sender`).
               *
               * If you are writing GSN compatible contracts, you need to override this function.
               */
              function _msgSenderERC721A() internal view virtual returns (address) {
                  return msg.sender;
              }
              /**
               * @dev Converts a uint256 to its ASCII string decimal representation.
               */
              function _toString(uint256 value) internal pure virtual returns (string memory str) {
                  assembly {
                      // The maximum value of a uint256 contains 78 digits (1 byte per digit), but
                      // we allocate 0xa0 bytes to keep the free memory pointer 32-byte word aligned.
                      // We will need 1 word for the trailing zeros padding, 1 word for the length,
                      // and 3 words for a maximum of 78 digits. Total: 5 * 0x20 = 0xa0.
                      let m := add(mload(0x40), 0xa0)
                      // Update the free memory pointer to allocate.
                      mstore(0x40, m)
                      // Assign the `str` to the end.
                      str := sub(m, 0x20)
                      // Zeroize the slot after the string.
                      mstore(str, 0)
                      // Cache the end of the memory to calculate the length later.
                      let end := str
                      // We write the string from rightmost digit to leftmost digit.
                      // The following is essentially a do-while loop that also handles the zero case.
                      // prettier-ignore
                      for { let temp := value } 1 {} {
                          str := sub(str, 1)
                          // Write the character to the pointer.
                          // The ASCII index of the '0' character is 48.
                          mstore8(str, add(48, mod(temp, 10)))
                          // Keep dividing `temp` until zero.
                          temp := div(temp, 10)
                          // prettier-ignore
                          if iszero(temp) { break }
                      }
                      let length := sub(end, str)
                      // Move the pointer 32 bytes leftwards to make room for the length.
                      str := sub(str, 0x20)
                      // Store the length.
                      mstore(str, length)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // ERC721A Contracts v4.2.3
          // Creator: Chiru Labs
          pragma solidity ^0.8.4;
          /**
           * @dev Interface of ERC721A.
           */
          interface IERC721A {
              /**
               * The caller must own the token or be an approved operator.
               */
              error ApprovalCallerNotOwnerNorApproved();
              /**
               * The token does not exist.
               */
              error ApprovalQueryForNonexistentToken();
              /**
               * Cannot query the balance for the zero address.
               */
              error BalanceQueryForZeroAddress();
              /**
               * Cannot mint to the zero address.
               */
              error MintToZeroAddress();
              /**
               * The quantity of tokens minted must be more than zero.
               */
              error MintZeroQuantity();
              /**
               * The token does not exist.
               */
              error OwnerQueryForNonexistentToken();
              /**
               * The caller must own the token or be an approved operator.
               */
              error TransferCallerNotOwnerNorApproved();
              /**
               * The token must be owned by `from`.
               */
              error TransferFromIncorrectOwner();
              /**
               * Cannot safely transfer to a contract that does not implement the
               * ERC721Receiver interface.
               */
              error TransferToNonERC721ReceiverImplementer();
              /**
               * Cannot transfer to the zero address.
               */
              error TransferToZeroAddress();
              /**
               * The token does not exist.
               */
              error URIQueryForNonexistentToken();
              /**
               * The `quantity` minted with ERC2309 exceeds the safety limit.
               */
              error MintERC2309QuantityExceedsLimit();
              /**
               * The `extraData` cannot be set on an unintialized ownership slot.
               */
              error OwnershipNotInitializedForExtraData();
              // =============================================================
              //                            STRUCTS
              // =============================================================
              struct TokenOwnership {
                  // The address of the owner.
                  address addr;
                  // Stores the start time of ownership with minimal overhead for tokenomics.
                  uint64 startTimestamp;
                  // Whether the token has been burned.
                  bool burned;
                  // Arbitrary data similar to `startTimestamp` that can be set via {_extraData}.
                  uint24 extraData;
              }
              // =============================================================
              //                         TOKEN COUNTERS
              // =============================================================
              /**
               * @dev Returns the total number of tokens in existence.
               * Burned tokens will reduce the count.
               * To get the total number of tokens minted, please see {_totalMinted}.
               */
              function totalSupply() external view returns (uint256);
              // =============================================================
              //                            IERC165
              // =============================================================
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
              // =============================================================
              //                            IERC721
              // =============================================================
              /**
               * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
               */
              event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
              /**
               * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
               */
              event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
              /**
               * @dev Emitted when `owner` enables or disables
               * (`approved`) `operator` to manage all of its assets.
               */
              event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
              /**
               * @dev Returns the number of tokens in `owner`'s account.
               */
              function balanceOf(address owner) external view returns (uint256 balance);
              /**
               * @dev Returns the owner of the `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function ownerOf(uint256 tokenId) external view returns (address owner);
              /**
               * @dev Safely transfers `tokenId` token from `from` to `to`,
               * checking first that contract recipients are aware of the ERC721 protocol
               * to prevent tokens from being forever locked.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must exist and be owned by `from`.
               * - If the caller is not `from`, it must be have been allowed to move
               * this token by either {approve} or {setApprovalForAll}.
               * - If `to` refers to a smart contract, it must implement
               * {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
               *
               * Emits a {Transfer} event.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes calldata data
              ) external payable;
              /**
               * @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) external payable;
              /**
               * @dev Transfers `tokenId` from `from` to `to`.
               *
               * WARNING: Usage of this method is discouraged, use {safeTransferFrom}
               * whenever possible.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must be owned by `from`.
               * - If the caller is not `from`, it must be approved to move this token
               * by either {approve} or {setApprovalForAll}.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) external payable;
              /**
               * @dev Gives permission to `to` to transfer `tokenId` token to another account.
               * The approval is cleared when the token is transferred.
               *
               * Only a single account can be approved at a time, so approving the
               * zero address clears previous approvals.
               *
               * Requirements:
               *
               * - The caller must own the token or be an approved operator.
               * - `tokenId` must exist.
               *
               * Emits an {Approval} event.
               */
              function approve(address to, uint256 tokenId) external payable;
              /**
               * @dev Approve or remove `operator` as an operator for the caller.
               * Operators can call {transferFrom} or {safeTransferFrom}
               * for any token owned by the caller.
               *
               * Requirements:
               *
               * - The `operator` cannot be the caller.
               *
               * Emits an {ApprovalForAll} event.
               */
              function setApprovalForAll(address operator, bool _approved) external;
              /**
               * @dev Returns the account approved for `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function getApproved(uint256 tokenId) external view returns (address operator);
              /**
               * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
               *
               * See {setApprovalForAll}.
               */
              function isApprovedForAll(address owner, address operator) external view returns (bool);
              // =============================================================
              //                        IERC721Metadata
              // =============================================================
              /**
               * @dev Returns the token collection name.
               */
              function name() external view returns (string memory);
              /**
               * @dev Returns the token collection symbol.
               */
              function symbol() external view returns (string memory);
              /**
               * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
               */
              function tokenURI(uint256 tokenId) external view returns (string memory);
              // =============================================================
              //                           IERC2309
              // =============================================================
              /**
               * @dev Emitted when tokens in `fromTokenId` to `toTokenId`
               * (inclusive) is transferred from `from` to `to`, as defined in the
               * [ERC2309](https://eips.ethereum.org/EIPS/eip-2309) standard.
               *
               * See {_mintERC2309} for more details.
               */
              event ConsecutiveTransfer(uint256 indexed fromTokenId, uint256 toTokenId, address indexed from, address indexed to);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.4;
          /// @notice Optimized and flexible operator filterer to abide to OpenSea's
          /// mandatory on-chain royalty enforcement in order for new collections to
          /// receive royalties.
          /// For more information, see:
          /// See: https://github.com/ProjectOpenSea/operator-filter-registry
          abstract contract OperatorFilterer {
              /// @dev The default OpenSea operator blocklist subscription.
              address internal constant _DEFAULT_SUBSCRIPTION = 0x3cc6CddA760b79bAfa08dF41ECFA224f810dCeB6;
              /// @dev The OpenSea operator filter registry.
              address internal constant _OPERATOR_FILTER_REGISTRY = 0x000000000000AAeB6D7670E522A718067333cd4E;
              /// @dev Registers the current contract to OpenSea's operator filter,
              /// and subscribe to the default OpenSea operator blocklist.
              /// Note: Will not revert nor update existing settings for repeated registration.
              function _registerForOperatorFiltering() internal virtual {
                  _registerForOperatorFiltering(_DEFAULT_SUBSCRIPTION, true);
              }
              /// @dev Registers the current contract to OpenSea's operator filter.
              /// Note: Will not revert nor update existing settings for repeated registration.
              function _registerForOperatorFiltering(address subscriptionOrRegistrantToCopy, bool subscribe)
                  internal
                  virtual
              {
                  /// @solidity memory-safe-assembly
                  assembly {
                      let functionSelector := 0x7d3e3dbe // `registerAndSubscribe(address,address)`.
                      // Clean the upper 96 bits of `subscriptionOrRegistrantToCopy` in case they are dirty.
                      subscriptionOrRegistrantToCopy := shr(96, shl(96, subscriptionOrRegistrantToCopy))
                      for {} iszero(subscribe) {} {
                          if iszero(subscriptionOrRegistrantToCopy) {
                              functionSelector := 0x4420e486 // `register(address)`.
                              break
                          }
                          functionSelector := 0xa0af2903 // `registerAndCopyEntries(address,address)`.
                          break
                      }
                      // Store the function selector.
                      mstore(0x00, shl(224, functionSelector))
                      // Store the `address(this)`.
                      mstore(0x04, address())
                      // Store the `subscriptionOrRegistrantToCopy`.
                      mstore(0x24, subscriptionOrRegistrantToCopy)
                      // Register into the registry.
                      if iszero(call(gas(), _OPERATOR_FILTER_REGISTRY, 0, 0x00, 0x44, 0x00, 0x04)) {
                          // If the function selector has not been overwritten,
                          // it is an out-of-gas error.
                          if eq(shr(224, mload(0x00)), functionSelector) {
                              // To prevent gas under-estimation.
                              revert(0, 0)
                          }
                      }
                      // Restore the part of the free memory pointer that was overwritten,
                      // which is guaranteed to be zero, because of Solidity's memory size limits.
                      mstore(0x24, 0)
                  }
              }
              /// @dev Modifier to guard a function and revert if the caller is a blocked operator.
              modifier onlyAllowedOperator(address from) virtual {
                  if (from != msg.sender) {
                      if (!_isPriorityOperator(msg.sender)) {
                          if (_operatorFilteringEnabled()) _revertIfBlocked(msg.sender);
                      }
                  }
                  _;
              }
              /// @dev Modifier to guard a function from approving a blocked operator..
              modifier onlyAllowedOperatorApproval(address operator) virtual {
                  if (!_isPriorityOperator(operator)) {
                      if (_operatorFilteringEnabled()) _revertIfBlocked(operator);
                  }
                  _;
              }
              /// @dev Helper function that reverts if the `operator` is blocked by the registry.
              function _revertIfBlocked(address operator) private view {
                  /// @solidity memory-safe-assembly
                  assembly {
                      // Store the function selector of `isOperatorAllowed(address,address)`,
                      // shifted left by 6 bytes, which is enough for 8tb of memory.
                      // We waste 6-3 = 3 bytes to save on 6 runtime gas (PUSH1 0x224 SHL).
                      mstore(0x00, 0xc6171134001122334455)
                      // Store the `address(this)`.
                      mstore(0x1a, address())
                      // Store the `operator`.
                      mstore(0x3a, operator)
                      // `isOperatorAllowed` always returns true if it does not revert.
                      if iszero(staticcall(gas(), _OPERATOR_FILTER_REGISTRY, 0x16, 0x44, 0x00, 0x00)) {
                          // Bubble up the revert if the staticcall reverts.
                          returndatacopy(0x00, 0x00, returndatasize())
                          revert(0x00, returndatasize())
                      }
                      // We'll skip checking if `from` is inside the blacklist.
                      // Even though that can block transferring out of wrapper contracts,
                      // we don't want tokens to be stuck.
                      // Restore the part of the free memory pointer that was overwritten,
                      // which is guaranteed to be zero, if less than 8tb of memory is used.
                      mstore(0x3a, 0)
                  }
              }
              /// @dev For deriving contracts to override, so that operator filtering
              /// can be turned on / off.
              /// Returns true by default.
              function _operatorFilteringEnabled() internal view virtual returns (bool) {
                  return true;
              }
              /// @dev For deriving contracts to override, so that preferred marketplaces can
              /// skip operator filtering, helping users save gas.
              /// Returns false for all inputs by default.
              function _isPriorityOperator(address) internal view virtual returns (bool) {
                  return false;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
          pragma solidity ^0.8.0;
          import "../utils/Context.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract Ownable is Context {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              constructor() {
                  _transferOwnership(_msgSender());
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  _checkOwner();
                  _;
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if the sender is not the owner.
               */
              function _checkOwner() internal view virtual {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions anymore. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby removing any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  _transferOwnership(address(0));
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  _transferOwnership(newOwner);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Internal function without access restriction.
               */
              function _transferOwnership(address newOwner) internal virtual {
                  address oldOwner = _owner;
                  _owner = newOwner;
                  emit OwnershipTransferred(oldOwner, newOwner);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.6.0) (interfaces/IERC2981.sol)
          pragma solidity ^0.8.0;
          import "../utils/introspection/IERC165.sol";
          /**
           * @dev Interface for the NFT Royalty Standard.
           *
           * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
           * support for royalty payments across all NFT marketplaces and ecosystem participants.
           *
           * _Available since v4.5._
           */
          interface IERC2981 is IERC165 {
              /**
               * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
               * exchange. The royalty amount is denominated and should be paid in that same unit of exchange.
               */
              function royaltyInfo(uint256 tokenId, uint256 salePrice)
                  external
                  view
                  returns (address receiver, uint256 royaltyAmount);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (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;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (token/common/ERC2981.sol)
          pragma solidity ^0.8.0;
          import "../../interfaces/IERC2981.sol";
          import "../../utils/introspection/ERC165.sol";
          /**
           * @dev Implementation of the NFT Royalty Standard, a standardized way to retrieve royalty payment information.
           *
           * Royalty information can be specified globally for all token ids via {_setDefaultRoyalty}, and/or individually for
           * specific token ids via {_setTokenRoyalty}. The latter takes precedence over the first.
           *
           * Royalty is specified as a fraction of sale price. {_feeDenominator} is overridable but defaults to 10000, meaning the
           * fee is specified in basis points by default.
           *
           * IMPORTANT: ERC-2981 only specifies a way to signal royalty information and does not enforce its payment. See
           * https://eips.ethereum.org/EIPS/eip-2981#optional-royalty-payments[Rationale] in the EIP. Marketplaces are expected to
           * voluntarily pay royalties together with sales, but note that this standard is not yet widely supported.
           *
           * _Available since v4.5._
           */
          abstract contract ERC2981 is IERC2981, ERC165 {
              struct RoyaltyInfo {
                  address receiver;
                  uint96 royaltyFraction;
              }
              RoyaltyInfo private _defaultRoyaltyInfo;
              mapping(uint256 => RoyaltyInfo) private _tokenRoyaltyInfo;
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC165) returns (bool) {
                  return interfaceId == type(IERC2981).interfaceId || super.supportsInterface(interfaceId);
              }
              /**
               * @inheritdoc IERC2981
               */
              function royaltyInfo(uint256 _tokenId, uint256 _salePrice) public view virtual override returns (address, uint256) {
                  RoyaltyInfo memory royalty = _tokenRoyaltyInfo[_tokenId];
                  if (royalty.receiver == address(0)) {
                      royalty = _defaultRoyaltyInfo;
                  }
                  uint256 royaltyAmount = (_salePrice * royalty.royaltyFraction) / _feeDenominator();
                  return (royalty.receiver, royaltyAmount);
              }
              /**
               * @dev The denominator with which to interpret the fee set in {_setTokenRoyalty} and {_setDefaultRoyalty} as a
               * fraction of the sale price. Defaults to 10000 so fees are expressed in basis points, but may be customized by an
               * override.
               */
              function _feeDenominator() internal pure virtual returns (uint96) {
                  return 10000;
              }
              /**
               * @dev Sets the royalty information that all ids in this contract will default to.
               *
               * Requirements:
               *
               * - `receiver` cannot be the zero address.
               * - `feeNumerator` cannot be greater than the fee denominator.
               */
              function _setDefaultRoyalty(address receiver, uint96 feeNumerator) internal virtual {
                  require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
                  require(receiver != address(0), "ERC2981: invalid receiver");
                  _defaultRoyaltyInfo = RoyaltyInfo(receiver, feeNumerator);
              }
              /**
               * @dev Removes default royalty information.
               */
              function _deleteDefaultRoyalty() internal virtual {
                  delete _defaultRoyaltyInfo;
              }
              /**
               * @dev Sets the royalty information for a specific token id, overriding the global default.
               *
               * Requirements:
               *
               * - `receiver` cannot be the zero address.
               * - `feeNumerator` cannot be greater than the fee denominator.
               */
              function _setTokenRoyalty(
                  uint256 tokenId,
                  address receiver,
                  uint96 feeNumerator
              ) internal virtual {
                  require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
                  require(receiver != address(0), "ERC2981: Invalid parameters");
                  _tokenRoyaltyInfo[tokenId] = RoyaltyInfo(receiver, feeNumerator);
              }
              /**
               * @dev Resets royalty information for the token id back to the global default.
               */
              function _resetTokenRoyalty(uint256 tokenId) internal virtual {
                  delete _tokenRoyaltyInfo[tokenId];
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)
          pragma solidity ^0.8.0;
          import "./math/Math.sol";
          /**
           * @dev String operations.
           */
          library Strings {
              bytes16 private constant _SYMBOLS = "0123456789abcdef";
              uint8 private constant _ADDRESS_LENGTH = 20;
              /**
               * @dev Converts a `uint256` to its ASCII `string` decimal representation.
               */
              function toString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      uint256 length = Math.log10(value) + 1;
                      string memory buffer = new string(length);
                      uint256 ptr;
                      /// @solidity memory-safe-assembly
                      assembly {
                          ptr := add(buffer, add(32, length))
                      }
                      while (true) {
                          ptr--;
                          /// @solidity memory-safe-assembly
                          assembly {
                              mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                          }
                          value /= 10;
                          if (value == 0) break;
                      }
                      return buffer;
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
               */
              function toHexString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      return toHexString(value, Math.log256(value) + 1);
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
               */
              function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                  bytes memory buffer = new bytes(2 * length + 2);
                  buffer[0] = "0";
                  buffer[1] = "x";
                  for (uint256 i = 2 * length + 1; i > 1; --i) {
                      buffer[i] = _SYMBOLS[value & 0xf];
                      value >>= 4;
                  }
                  require(value == 0, "Strings: hex length insufficient");
                  return string(buffer);
              }
              /**
               * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
               */
              function toHexString(address addr) internal pure returns (string memory) {
                  return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/MerkleProof.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev These functions deal with verification of Merkle Tree proofs.
           *
           * The tree and the proofs can be generated using our
           * https://github.com/OpenZeppelin/merkle-tree[JavaScript library].
           * You will find a quickstart guide in the readme.
           *
           * WARNING: You should avoid using leaf values that are 64 bytes long prior to
           * hashing, or use a hash function other than keccak256 for hashing leaves.
           * This is because the concatenation of a sorted pair of internal nodes in
           * the merkle tree could be reinterpreted as a leaf value.
           * OpenZeppelin's JavaScript library generates merkle trees that are safe
           * against this attack out of the box.
           */
          library MerkleProof {
              /**
               * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
               * defined by `root`. For this, a `proof` must be provided, containing
               * sibling hashes on the branch from the leaf to the root of the tree. Each
               * pair of leaves and each pair of pre-images are assumed to be sorted.
               */
              function verify(
                  bytes32[] memory proof,
                  bytes32 root,
                  bytes32 leaf
              ) internal pure returns (bool) {
                  return processProof(proof, leaf) == root;
              }
              /**
               * @dev Calldata version of {verify}
               *
               * _Available since v4.7._
               */
              function verifyCalldata(
                  bytes32[] calldata proof,
                  bytes32 root,
                  bytes32 leaf
              ) internal pure returns (bool) {
                  return processProofCalldata(proof, leaf) == root;
              }
              /**
               * @dev Returns the rebuilt hash obtained by traversing a Merkle tree up
               * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
               * hash matches the root of the tree. When processing the proof, the pairs
               * of leafs & pre-images are assumed to be sorted.
               *
               * _Available since v4.4._
               */
              function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
                  bytes32 computedHash = leaf;
                  for (uint256 i = 0; i < proof.length; i++) {
                      computedHash = _hashPair(computedHash, proof[i]);
                  }
                  return computedHash;
              }
              /**
               * @dev Calldata version of {processProof}
               *
               * _Available since v4.7._
               */
              function processProofCalldata(bytes32[] calldata proof, bytes32 leaf) internal pure returns (bytes32) {
                  bytes32 computedHash = leaf;
                  for (uint256 i = 0; i < proof.length; i++) {
                      computedHash = _hashPair(computedHash, proof[i]);
                  }
                  return computedHash;
              }
              /**
               * @dev Returns true if the `leaves` can be simultaneously proven to be a part of a merkle tree defined by
               * `root`, according to `proof` and `proofFlags` as described in {processMultiProof}.
               *
               * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
               *
               * _Available since v4.7._
               */
              function multiProofVerify(
                  bytes32[] memory proof,
                  bool[] memory proofFlags,
                  bytes32 root,
                  bytes32[] memory leaves
              ) internal pure returns (bool) {
                  return processMultiProof(proof, proofFlags, leaves) == root;
              }
              /**
               * @dev Calldata version of {multiProofVerify}
               *
               * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
               *
               * _Available since v4.7._
               */
              function multiProofVerifyCalldata(
                  bytes32[] calldata proof,
                  bool[] calldata proofFlags,
                  bytes32 root,
                  bytes32[] memory leaves
              ) internal pure returns (bool) {
                  return processMultiProofCalldata(proof, proofFlags, leaves) == root;
              }
              /**
               * @dev Returns the root of a tree reconstructed from `leaves` and sibling nodes in `proof`. The reconstruction
               * proceeds by incrementally reconstructing all inner nodes by combining a leaf/inner node with either another
               * leaf/inner node or a proof sibling node, depending on whether each `proofFlags` item is true or false
               * respectively.
               *
               * CAUTION: Not all merkle trees admit multiproofs. To use multiproofs, it is sufficient to ensure that: 1) the tree
               * is complete (but not necessarily perfect), 2) the leaves to be proven are in the opposite order they are in the
               * tree (i.e., as seen from right to left starting at the deepest layer and continuing at the next layer).
               *
               * _Available since v4.7._
               */
              function processMultiProof(
                  bytes32[] memory proof,
                  bool[] memory proofFlags,
                  bytes32[] memory leaves
              ) internal pure returns (bytes32 merkleRoot) {
                  // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
                  // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
                  // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
                  // the merkle tree.
                  uint256 leavesLen = leaves.length;
                  uint256 totalHashes = proofFlags.length;
                  // Check proof validity.
                  require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");
                  // The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
                  // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
                  bytes32[] memory hashes = new bytes32[](totalHashes);
                  uint256 leafPos = 0;
                  uint256 hashPos = 0;
                  uint256 proofPos = 0;
                  // At each step, we compute the next hash using two values:
                  // - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
                  //   get the next hash.
                  // - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
                  //   `proof` array.
                  for (uint256 i = 0; i < totalHashes; i++) {
                      bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
                      bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
                      hashes[i] = _hashPair(a, b);
                  }
                  if (totalHashes > 0) {
                      return hashes[totalHashes - 1];
                  } else if (leavesLen > 0) {
                      return leaves[0];
                  } else {
                      return proof[0];
                  }
              }
              /**
               * @dev Calldata version of {processMultiProof}.
               *
               * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
               *
               * _Available since v4.7._
               */
              function processMultiProofCalldata(
                  bytes32[] calldata proof,
                  bool[] calldata proofFlags,
                  bytes32[] memory leaves
              ) internal pure returns (bytes32 merkleRoot) {
                  // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
                  // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
                  // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
                  // the merkle tree.
                  uint256 leavesLen = leaves.length;
                  uint256 totalHashes = proofFlags.length;
                  // Check proof validity.
                  require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");
                  // The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
                  // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
                  bytes32[] memory hashes = new bytes32[](totalHashes);
                  uint256 leafPos = 0;
                  uint256 hashPos = 0;
                  uint256 proofPos = 0;
                  // At each step, we compute the next hash using two values:
                  // - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
                  //   get the next hash.
                  // - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
                  //   `proof` array.
                  for (uint256 i = 0; i < totalHashes; i++) {
                      bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
                      bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
                      hashes[i] = _hashPair(a, b);
                  }
                  if (totalHashes > 0) {
                      return hashes[totalHashes - 1];
                  } else if (leavesLen > 0) {
                      return leaves[0];
                  } else {
                      return proof[0];
                  }
              }
              function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32) {
                  return a < b ? _efficientHash(a, b) : _efficientHash(b, a);
              }
              function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      mstore(0x00, a)
                      mstore(0x20, b)
                      value := keccak256(0x00, 0x40)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
          pragma solidity ^0.8.0;
          import "./IERC165.sol";
          /**
           * @dev Implementation of the {IERC165} interface.
           *
           * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
           * for the additional interface id that will be supported. For example:
           *
           * ```solidity
           * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
           *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
           * }
           * ```
           *
           * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
           */
          abstract contract ERC165 is IERC165 {
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IERC165).interfaceId;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC165 standard, as defined in the
           * https://eips.ethereum.org/EIPS/eip-165[EIP].
           *
           * Implementers can declare support of contract interfaces, which can then be
           * queried by others ({ERC165Checker}).
           *
           * For an implementation, see {ERC165}.
           */
          interface IERC165 {
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30 000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Standard math utilities missing in the Solidity language.
           */
          library Math {
              enum Rounding {
                  Down, // Toward negative infinity
                  Up, // Toward infinity
                  Zero // Toward zero
              }
              /**
               * @dev Returns the largest of two numbers.
               */
              function max(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a > b ? a : b;
              }
              /**
               * @dev Returns the smallest of two numbers.
               */
              function min(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a < b ? a : b;
              }
              /**
               * @dev Returns the average of two numbers. The result is rounded towards
               * zero.
               */
              function average(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b) / 2 can overflow.
                  return (a & b) + (a ^ b) / 2;
              }
              /**
               * @dev Returns the ceiling of the division of two numbers.
               *
               * This differs from standard division with `/` in that it rounds up instead
               * of rounding down.
               */
              function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b - 1) / b can overflow on addition, so we distribute.
                  return a == 0 ? 0 : (a - 1) / b + 1;
              }
              /**
               * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
               * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
               * with further edits by Uniswap Labs also under MIT license.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator
              ) internal pure returns (uint256 result) {
                  unchecked {
                      // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                      // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                      // variables such that product = prod1 * 2^256 + prod0.
                      uint256 prod0; // Least significant 256 bits of the product
                      uint256 prod1; // Most significant 256 bits of the product
                      assembly {
                          let mm := mulmod(x, y, not(0))
                          prod0 := mul(x, y)
                          prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                      }
                      // Handle non-overflow cases, 256 by 256 division.
                      if (prod1 == 0) {
                          return prod0 / denominator;
                      }
                      // Make sure the result is less than 2^256. Also prevents denominator == 0.
                      require(denominator > prod1);
                      ///////////////////////////////////////////////
                      // 512 by 256 division.
                      ///////////////////////////////////////////////
                      // Make division exact by subtracting the remainder from [prod1 prod0].
                      uint256 remainder;
                      assembly {
                          // Compute remainder using mulmod.
                          remainder := mulmod(x, y, denominator)
                          // Subtract 256 bit number from 512 bit number.
                          prod1 := sub(prod1, gt(remainder, prod0))
                          prod0 := sub(prod0, remainder)
                      }
                      // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                      // See https://cs.stackexchange.com/q/138556/92363.
                      // Does not overflow because the denominator cannot be zero at this stage in the function.
                      uint256 twos = denominator & (~denominator + 1);
                      assembly {
                          // Divide denominator by twos.
                          denominator := div(denominator, twos)
                          // Divide [prod1 prod0] by twos.
                          prod0 := div(prod0, twos)
                          // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                          twos := add(div(sub(0, twos), twos), 1)
                      }
                      // Shift in bits from prod1 into prod0.
                      prod0 |= prod1 * twos;
                      // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                      // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                      // four bits. That is, denominator * inv = 1 mod 2^4.
                      uint256 inverse = (3 * denominator) ^ 2;
                      // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                      // in modular arithmetic, doubling the correct bits in each step.
                      inverse *= 2 - denominator * inverse; // inverse mod 2^8
                      inverse *= 2 - denominator * inverse; // inverse mod 2^16
                      inverse *= 2 - denominator * inverse; // inverse mod 2^32
                      inverse *= 2 - denominator * inverse; // inverse mod 2^64
                      inverse *= 2 - denominator * inverse; // inverse mod 2^128
                      inverse *= 2 - denominator * inverse; // inverse mod 2^256
                      // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                      // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                      // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                      // is no longer required.
                      result = prod0 * inverse;
                      return result;
                  }
              }
              /**
               * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator,
                  Rounding rounding
              ) internal pure returns (uint256) {
                  uint256 result = mulDiv(x, y, denominator);
                  if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                      result += 1;
                  }
                  return result;
              }
              /**
               * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
               *
               * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
               */
              function sqrt(uint256 a) internal pure returns (uint256) {
                  if (a == 0) {
                      return 0;
                  }
                  // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                  //
                  // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                  // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
                  //
                  // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
                  // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
                  // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
                  //
                  // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
                  uint256 result = 1 << (log2(a) >> 1);
                  // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                  // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                  // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                  // into the expected uint128 result.
                  unchecked {
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      return min(result, a / result);
                  }
              }
              /**
               * @notice Calculates sqrt(a), following the selected rounding direction.
               */
              function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = sqrt(a);
                      return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 2, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 128;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 64;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 32;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 16;
                      }
                      if (value >> 8 > 0) {
                          value >>= 8;
                          result += 8;
                      }
                      if (value >> 4 > 0) {
                          value >>= 4;
                          result += 4;
                      }
                      if (value >> 2 > 0) {
                          value >>= 2;
                          result += 2;
                      }
                      if (value >> 1 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log2(value);
                      return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 10, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >= 10**64) {
                          value /= 10**64;
                          result += 64;
                      }
                      if (value >= 10**32) {
                          value /= 10**32;
                          result += 32;
                      }
                      if (value >= 10**16) {
                          value /= 10**16;
                          result += 16;
                      }
                      if (value >= 10**8) {
                          value /= 10**8;
                          result += 8;
                      }
                      if (value >= 10**4) {
                          value /= 10**4;
                          result += 4;
                      }
                      if (value >= 10**2) {
                          value /= 10**2;
                          result += 2;
                      }
                      if (value >= 10**1) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log10(value);
                      return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 256, rounded down, of a positive value.
               * Returns 0 if given 0.
               *
               * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
               */
              function log256(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 16;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 8;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 4;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 2;
                      }
                      if (value >> 8 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log256(value);
                      return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
                  }
              }
          }
          // SPDX-License-Identifier: CC0-1.0
          pragma solidity >=0.8.10 <0.9.0;
          /**
           * @title An immutable registry contract to be deployed as a standalone primitive
           * @dev See EIP-5639, new project launches can read previous cold wallet -> hot wallet delegations
           * from here and integrate those permissions into their flow
           */
          interface IDelegationRegistry {
              /// @notice Delegation type
              enum DelegationType {
                  NONE,
                  ALL,
                  CONTRACT,
                  TOKEN
              }
              /// @notice Info about a single delegation, used for onchain enumeration
              struct DelegationInfo {
                  DelegationType type_;
                  address vault;
                  address delegate;
                  address contract_;
                  uint256 tokenId;
              }
              /// @notice Info about a single contract-level delegation
              struct ContractDelegation {
                  address contract_;
                  address delegate;
              }
              /// @notice Info about a single token-level delegation
              struct TokenDelegation {
                  address contract_;
                  uint256 tokenId;
                  address delegate;
              }
              /// @notice Emitted when a user delegates their entire wallet
              event DelegateForAll(address vault, address delegate, bool value);
              /// @notice Emitted when a user delegates a specific contract
              event DelegateForContract(address vault, address delegate, address contract_, bool value);
              /// @notice Emitted when a user delegates a specific token
              event DelegateForToken(address vault, address delegate, address contract_, uint256 tokenId, bool value);
              /// @notice Emitted when a user revokes all delegations
              event RevokeAllDelegates(address vault);
              /// @notice Emitted when a user revoes all delegations for a given delegate
              event RevokeDelegate(address vault, address delegate);
              /**
               * -----------  WRITE -----------
               */
              /**
               * @notice Allow the delegate to act on your behalf for all contracts
               * @param delegate The hotwallet to act on your behalf
               * @param value Whether to enable or disable delegation for this address, true for setting and false for revoking
               */
              function delegateForAll(address delegate, bool value) external;
              /**
               * @notice Allow the delegate to act on your behalf for a specific contract
               * @param delegate The hotwallet to act on your behalf
               * @param contract_ The address for the contract you're delegating
               * @param value Whether to enable or disable delegation for this address, true for setting and false for revoking
               */
              function delegateForContract(address delegate, address contract_, bool value) external;
              /**
               * @notice Allow the delegate to act on your behalf for a specific token
               * @param delegate The hotwallet to act on your behalf
               * @param contract_ The address for the contract you're delegating
               * @param tokenId The token id for the token you're delegating
               * @param value Whether to enable or disable delegation for this address, true for setting and false for revoking
               */
              function delegateForToken(address delegate, address contract_, uint256 tokenId, bool value) external;
              /**
               * @notice Revoke all delegates
               */
              function revokeAllDelegates() external;
              /**
               * @notice Revoke a specific delegate for all their permissions
               * @param delegate The hotwallet to revoke
               */
              function revokeDelegate(address delegate) external;
              /**
               * @notice Remove yourself as a delegate for a specific vault
               * @param vault The vault which delegated to the msg.sender, and should be removed
               */
              function revokeSelf(address vault) external;
              /**
               * -----------  READ -----------
               */
              /**
               * @notice Returns all active delegations a given delegate is able to claim on behalf of
               * @param delegate The delegate that you would like to retrieve delegations for
               * @return info Array of DelegationInfo structs
               */
              function getDelegationsByDelegate(address delegate) external view returns (DelegationInfo[] memory);
              /**
               * @notice Returns an array of wallet-level delegates for a given vault
               * @param vault The cold wallet who issued the delegation
               * @return addresses Array of wallet-level delegates for a given vault
               */
              function getDelegatesForAll(address vault) external view returns (address[] memory);
              /**
               * @notice Returns an array of contract-level delegates for a given vault and contract
               * @param vault The cold wallet who issued the delegation
               * @param contract_ The address for the contract you're delegating
               * @return addresses Array of contract-level delegates for a given vault and contract
               */
              function getDelegatesForContract(address vault, address contract_) external view returns (address[] memory);
              /**
               * @notice Returns an array of contract-level delegates for a given vault's token
               * @param vault The cold wallet who issued the delegation
               * @param contract_ The address for the contract holding the token
               * @param tokenId The token id for the token you're delegating
               * @return addresses Array of contract-level delegates for a given vault's token
               */
              function getDelegatesForToken(address vault, address contract_, uint256 tokenId)
                  external
                  view
                  returns (address[] memory);
              /**
               * @notice Returns all contract-level delegations for a given vault
               * @param vault The cold wallet who issued the delegations
               * @return delegations Array of ContractDelegation structs
               */
              function getContractLevelDelegations(address vault)
                  external
                  view
                  returns (ContractDelegation[] memory delegations);
              /**
               * @notice Returns all token-level delegations for a given vault
               * @param vault The cold wallet who issued the delegations
               * @return delegations Array of TokenDelegation structs
               */
              function getTokenLevelDelegations(address vault) external view returns (TokenDelegation[] memory delegations);
              /**
               * @notice Returns true if the address is delegated to act on the entire vault
               * @param delegate The hotwallet to act on your behalf
               * @param vault The cold wallet who issued the delegation
               */
              function checkDelegateForAll(address delegate, address vault) external view returns (bool);
              /**
               * @notice Returns true if the address is delegated to act on your behalf for a token contract or an entire vault
               * @param delegate The hotwallet to act on your behalf
               * @param contract_ The address for the contract you're delegating
               * @param vault The cold wallet who issued the delegation
               */
              function checkDelegateForContract(address delegate, address vault, address contract_)
                  external
                  view
                  returns (bool);
              /**
               * @notice Returns true if the address is delegated to act on your behalf for a specific token, the token's contract or an entire vault
               * @param delegate The hotwallet to act on your behalf
               * @param contract_ The address for the contract you're delegating
               * @param tokenId The token id for the token you're delegating
               * @param vault The cold wallet who issued the delegation
               */
              function checkDelegateForToken(address delegate, address vault, address contract_, uint256 tokenId)
                  external
                  view
                  returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.10 <0.9.0;
          /*
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          import {ERC2981} from "openzeppelin/token/common/ERC2981.sol";
          import {ERC721A} from "erc721a/contracts/ERC721A.sol";
          import {IDelegationRegistry} from "./IDelegationRegistry.sol";
          import {Lists} from "./Lists.sol";
          import {OperatorFilterer} from "closedsea/OperatorFilterer.sol";
          import {Ownable} from "openzeppelin/access/Ownable.sol";
          import {ReentrancyGuard} from "openzeppelin/security/ReentrancyGuard.sol";
          contract IronPawGang is ERC721A, ERC2981, Ownable, OperatorFilterer, ReentrancyGuard {
              using Lists for Lists.Store;
              event DriverSwap(uint256 indexed tokenA, uint256 indexed tokenB);
              // Mint
              error ContractMintDisallowedError();
              error IncorrectAmountError();
              error InvalidProofError();
              error ListDisabledError();
              error MaxAmountExceededError();
              error MaxSupplyExceededError();
              error SaleStateClosedError();
              error UnknownListError();
              error MaxPerTransactionExceededError();
              error MissingDelegationError();
              // Drivers
              error InvalidSwapError();
              error OutOfBoundsError();
              error SenderDoesntOwnTokenError();
              error RecentSwapTransferProhibitedError();
              error DriverSwappingDisabledError();
              string public PROVENANCE_HASH;
              uint256 constant MAX_SUPPLY = 4000;
              uint256 constant price = 0.15 ether;
              uint256 public maxMintPerTransaction = 1;
              bool public driverSwapEnabled;
              uint256 public postSwapTransferLockDuration = 86400;
              mapping(uint256 => uint256) private _swappedDriverIDs;
              mapping(uint256 => uint256) private _lastSwapTimes;
              string public baseURI;
              IDelegationRegistry public delegationRegistry;
              enum SaleState {
                  Closed,
                  Private,
                  Public
              }
              SaleState public saleState = SaleState.Closed;
              Lists.Store private _lists;
              bool public operatorFilteringEnabled;
              constructor(string memory initialBaseURI, address payable royaltiesReceiver, address delegationRegistryAddress)
                  ERC721A("Iron Paw Gang", "IPG")
              {
                  baseURI = initialBaseURI;
                  setRoyaltyInfo(royaltiesReceiver, 500);
                  delegationRegistry = IDelegationRegistry(delegationRegistryAddress);
                  _registerForOperatorFiltering();
                  operatorFilteringEnabled = true;
              }
              function withdraw(address payable destination) external onlyOwner {
                  destination.transfer(address(this).balance);
              }
              // Metadata
              function setProvenanceHash(string calldata hash) external onlyOwner {
                  PROVENANCE_HASH = hash;
              }
              function setBaseURI(string memory uri) external onlyOwner {
                  baseURI = uri;
              }
              function _baseURI() internal view override returns (string memory) {
                  return baseURI;
              }
              // Modifiers
              modifier verifySaleState(SaleState requiredState) {
                  if (saleState != requiredState) revert SaleStateClosedError();
                  _;
              }
              modifier verifyAmount(uint256 amount, uint256 price_) {
                  if (msg.value != price_ * amount) revert IncorrectAmountError();
                  _;
              }
              modifier verifyMaxPerTransaction(uint256 amount) {
                  if (amount > maxMintPerTransaction) revert MaxPerTransactionExceededError();
                  _;
              }
              modifier verifyAvailableSupply(uint256 amount) {
                  if (totalSupply() + amount > MAX_SUPPLY) revert MaxSupplyExceededError();
                  _;
              }
              modifier verifyListExists(string calldata list) {
                  if (_lists.roots[list] == "") revert UnknownListError();
                  if (!_lists.active[list]) revert ListDisabledError();
                  _;
              }
              // Driver swaps
              function setDriverSwapEnabled(bool enabled) external onlyOwner {
                  driverSwapEnabled = enabled;
              }
              function setPostSwapTransferLockDuration(uint256 secs) external onlyOwner {
                  postSwapTransferLockDuration = secs;
              }
              function driverId(uint256 tokenId) public view returns (uint256) {
                  if (tokenId < 1 || tokenId > MAX_SUPPLY) revert OutOfBoundsError();
                  uint256 swappedId = _swappedDriverIDs[tokenId];
                  if (swappedId != 0) return swappedId;
                  return tokenId;
              }
              function lastSwapTime(uint256 tokenId) public view returns (uint256) {
                  return _lastSwapTimes[tokenId];
              }
              function swapDrivers(uint256 a, uint256 b) external nonReentrant {
                  if (!driverSwapEnabled) revert DriverSwappingDisabledError();
                  if (a == b) revert InvalidSwapError();
                  if (ownerOf(a) != _msgSender() && ownerOf(b) != _msgSender()) revert SenderDoesntOwnTokenError();
                  uint256 aDriver = driverId(a);
                  uint256 bDriver = driverId(b);
                  _swappedDriverIDs[a] = bDriver;
                  _swappedDriverIDs[b] = aDriver;
                  _lastSwapTimes[a] = block.timestamp;
                  _lastSwapTimes[b] = block.timestamp;
                  emit DriverSwap(a, b);
              }
              function _beforeTokenTransfers(address, address, uint256 startTokenId, uint256 quantity) internal view override {
                  uint256 tokenId = startTokenId;
                  for (uint256 end = tokenId + quantity; tokenId < end; ++tokenId) {
                      if (lastSwapTime(tokenId) == 0) continue;
                      if (block.timestamp - lastSwapTime(tokenId) < postSwapTransferLockDuration) {
                          revert RecentSwapTransferProhibitedError();
                      }
                  }
              }
              // Minting
              function setSaleState(SaleState state) external onlyOwner {
                  saleState = state;
              }
              function setListRoot(string calldata list, bytes32 root, bool active) public onlyOwner {
                  _lists.roots[list] = root;
                  _lists.active[list] = active;
              }
              function setListRoot(string calldata list, bytes32 root) external onlyOwner {
                  setListRoot(list, root, true);
              }
              function setListActive(string calldata list, bool active) external onlyOwner {
                  _lists.active[list] = active;
              }
              function setMaxPerTransaction(uint256 max) external onlyOwner {
                  maxMintPerTransaction = max;
              }
              function listMintCount(string calldata list, address account) public view returns (uint256) {
                  return _lists.usageCount(list, account);
              }
              function mintListed(
                  string calldata list,
                  uint256 amount,
                  bytes32[] calldata merkleProof,
                  uint256 maxAmount,
                  address onBehalfOf
              )
                  public
                  payable
                  verifySaleState(SaleState.Private)
                  verifyAvailableSupply(amount)
                  verifyListExists(list)
                  verifyAmount(amount, price)
                  nonReentrant
              {
                  if (!_lists.verify(list, merkleProof, onBehalfOf, maxAmount)) revert InvalidProofError();
                  if (_msgSender() != onBehalfOf) {
                      if (!delegationRegistry.checkDelegateForContract(_msgSender(), onBehalfOf, address(this))) {
                          revert MissingDelegationError();
                      }
                  }
                  _checkMaxAmountAndRecordUsage(list, onBehalfOf, amount, maxAmount);
                  _mint(_msgSender(), amount);
              }
              function mintListed(string calldata list, uint256 amount, bytes32[] calldata merkleProof, uint256 maxAmount)
                  public
                  payable
              {
                  mintListed(list, amount, merkleProof, maxAmount, _msgSender());
              }
              function mintMonke(string calldata list, uint256 amount, bytes32[] calldata merkleProof, uint256 maxAmount)
                  public
                  payable
                  verifySaleState(SaleState.Private)
                  verifyAvailableSupply(amount)
                  verifyListExists(list)
                  verifyAmount(amount, 0)
                  nonReentrant
              {
                  if (!_lists.verify(list, merkleProof, _msgSender(), maxAmount)) revert InvalidProofError();
                  _checkMaxAmountAndRecordUsage(list, _msgSender(), amount, maxAmount);
                  _mint(_msgSender(), amount);
              }
              function _checkMaxAmountAndRecordUsage(string calldata list, address account, uint256 amount, uint256 maxAmount)
                  private
              {
                  uint256 alreadyUsed = _lists.usageCount(list, account);
                  if (amount > maxAmount - alreadyUsed) revert MaxAmountExceededError();
                  _lists.incrementUsageCount(list, account, amount);
              }
              function mintPublic(uint256 amount)
                  external
                  payable
                  verifySaleState(SaleState.Public)
                  verifyAmount(amount, price)
                  verifyAvailableSupply(amount)
                  verifyMaxPerTransaction(amount)
                  nonReentrant
              {
                  if (_msgSender() != tx.origin) revert ContractMintDisallowedError();
                  _mint(_msgSender(), amount);
              }
              function ownerMint(address to, uint256 amount) external onlyOwner verifyAvailableSupply(amount) {
                  _mint(to, amount);
              }
              // ERC721A
              function _startTokenId() internal view virtual override returns (uint256) {
                  return 1;
              }
              // OperatorFilterer
              function setApprovalForAll(address operator, bool approved)
                  public
                  override(ERC721A)
                  onlyAllowedOperatorApproval(operator)
              {
                  super.setApprovalForAll(operator, approved);
              }
              function approve(address operator, uint256 tokenId)
                  public
                  payable
                  override(ERC721A)
                  onlyAllowedOperatorApproval(operator)
              {
                  super.approve(operator, tokenId);
              }
              function transferFrom(address from, address to, uint256 tokenId)
                  public
                  payable
                  override(ERC721A)
                  onlyAllowedOperator(from)
              {
                  super.transferFrom(from, to, tokenId);
              }
              function safeTransferFrom(address from, address to, uint256 tokenId)
                  public
                  payable
                  override(ERC721A)
                  onlyAllowedOperator(from)
              {
                  super.safeTransferFrom(from, to, tokenId);
              }
              function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data)
                  public
                  payable
                  override(ERC721A)
                  onlyAllowedOperator(from)
              {
                  super.safeTransferFrom(from, to, tokenId, data);
              }
              function setOperatorFilteringEnabled(bool value) public onlyOwner {
                  operatorFilteringEnabled = value;
              }
              function _operatorFilteringEnabled() internal view override returns (bool) {
                  return operatorFilteringEnabled;
              }
              function _isPriorityOperator(address operator) internal pure override returns (bool) {
                  // OpenSea Seaport Conduit:
                  // https://etherscan.io/address/0x1E0049783F008A0085193E00003D00cd54003c71
                  // https://goerli.etherscan.io/address/0x1E0049783F008A0085193E00003D00cd54003c71
                  return operator == address(0x1E0049783F008A0085193E00003D00cd54003c71);
              }
              // IERC2981
              function setRoyaltyInfo(address payable receiver, uint96 numerator) public onlyOwner {
                  _setDefaultRoyalty(receiver, numerator);
              }
              // ERC165
              function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721A, ERC2981) returns (bool) {
                  return ERC721A.supportsInterface(interfaceId) || ERC2981.supportsInterface(interfaceId);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.10 <0.9.0;
          import {Strings} from "openzeppelin/utils/Strings.sol";
          import {MerkleProof} from "openzeppelin/utils/cryptography/MerkleProof.sol";
          library Lists {
              using Strings for uint256;
              struct Store {
                  mapping(string => bytes32) roots;
                  mapping(string => bool) active;
                  mapping(bytes32 => uint256) usageCounts;
              }
              function verify(
                  Store storage store,
                  string calldata list,
                  bytes32[] calldata merkleProof,
                  address sender,
                  uint256 maxAmount
              ) internal view returns (bool) {
                  bytes32 leaf = keccak256(abi.encodePacked(sender, maxAmount.toString()));
                  return MerkleProof.verify(merkleProof, store.roots[list], leaf);
              }
              function usageCount(Store storage store, string calldata list, address account) internal view returns (uint256) {
                  return store.usageCounts[countKey(list, account)];
              }
              function incrementUsageCount(Store storage store, string calldata list, address account, uint256 amount) internal {
                  store.usageCounts[countKey(list, account)] += amount;
              }
              function countKey(string calldata list, address account) private pure returns (bytes32) {
                  return keccak256(abi.encodePacked(list, account));
              }
          }
          

          File 3 of 5: BlurExchange
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
          import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
          import "./lib/ReentrancyGuarded.sol";
          import "./lib/EIP712.sol";
          import "./lib/MerkleVerifier.sol";
          import "./interfaces/IBlurExchange.sol";
          import "./interfaces/IBlurPool.sol";
          import "./interfaces/IExecutionDelegate.sol";
          import "./interfaces/IPolicyManager.sol";
          import "./interfaces/IMatchingPolicy.sol";
          import {
            Side,
            SignatureVersion,
            AssetType,
            Fee,
            Order,
            Input,
            Execution
          } from "./lib/OrderStructs.sol";
          /**
           * @title BlurExchange
           * @dev Core Blur exchange contract
           */
          contract BlurExchange is IBlurExchange, ReentrancyGuarded, EIP712, OwnableUpgradeable, UUPSUpgradeable {
              /* Auth */
              uint256 public isOpen;
              modifier whenOpen() {
                  require(isOpen == 1, "Closed");
                  _;
              }
              modifier setupExecution() {
                  require(!isInternal, "Unsafe call"); // add redundant re-entrancy check for clarity
                  remainingETH = msg.value;
                  isInternal = true;
                  _;
                  remainingETH = 0;
                  isInternal = false;
              }
              modifier internalCall() {
                  require(isInternal, "Unsafe call");
                  _;
              }
              event Opened();
              event Closed();
              function open() external onlyOwner {
                  isOpen = 1;
                  emit Opened();
              }
              function close() external onlyOwner {
                  isOpen = 0;
                  emit Closed();
              }
              // required by the OZ UUPS module
              function _authorizeUpgrade(address) internal override onlyOwner {}
              /* Constants */
              string public constant NAME = "Blur Exchange";
              string public constant VERSION = "1.0";
              uint256 public constant INVERSE_BASIS_POINT = 10_000;
              address public constant WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
              address public constant POOL = 0x0000000000A39bb272e79075ade125fd351887Ac;
              uint256 private constant MAX_FEE_RATE = 250;
              /* Variables */
              IExecutionDelegate public executionDelegate;
              IPolicyManager public policyManager;
              address public oracle;
              uint256 public blockRange;
              /* Storage */
              mapping(bytes32 => bool) public cancelledOrFilled;
              mapping(address => uint256) public nonces;
              bool public isInternal = false;
              uint256 public remainingETH = 0;
              /* Governance Variables */
              uint256 public feeRate;
              address public feeRecipient;
              address public governor;
              /* Events */
              event OrdersMatched(
                  address indexed maker,
                  address indexed taker,
                  Order sell,
                  bytes32 sellHash,
                  Order buy,
                  bytes32 buyHash
              );
              event OrderCancelled(bytes32 hash);
              event NonceIncremented(address indexed trader, uint256 newNonce);
              event NewExecutionDelegate(IExecutionDelegate indexed executionDelegate);
              event NewPolicyManager(IPolicyManager indexed policyManager);
              event NewOracle(address indexed oracle);
              event NewBlockRange(uint256 blockRange);
              event NewFeeRate(uint256 feeRate);
              event NewFeeRecipient(address feeRecipient);
              event NewGovernor(address governor);
              constructor() {
                _disableInitializers();
              }
              /* Constructor (for ERC1967) */
              function initialize(
                  IExecutionDelegate _executionDelegate,
                  IPolicyManager _policyManager,
                  address _oracle,
                  uint _blockRange
              ) external initializer {
                  __Ownable_init();
                  isOpen = 1;
                  DOMAIN_SEPARATOR = _hashDomain(EIP712Domain({
                      name              : NAME,
                      version           : VERSION,
                      chainId           : block.chainid,
                      verifyingContract : address(this)
                  }));
                  executionDelegate = _executionDelegate;
                  policyManager = _policyManager;
                  oracle = _oracle;
                  blockRange = _blockRange;
              }
              /* External Functions */
              /**
               * @dev _execute wrapper
               * @param sell Sell input
               * @param buy Buy input
               */
              function execute(Input calldata sell, Input calldata buy)
                  external
                  payable
                  whenOpen
                  setupExecution
              {
                  _execute(sell, buy);
                  _returnDust();
              }
              /**
               * @dev Bulk execute multiple matches
               * @param executions Potential buy/sell matches
               */
              function bulkExecute(Execution[] calldata executions)
                  external
                  payable
                  whenOpen
                  setupExecution
              {
                  /*
                  REFERENCE
                  uint256 executionsLength = executions.length;
                  for (uint8 i=0; i < executionsLength; i++) {
                      bytes memory data = abi.encodeWithSelector(this._execute.selector, executions[i].sell, executions[i].buy);
                      (bool success,) = address(this).delegatecall(data);
                  }
                  _returnDust(remainingETH);
                  */
                  uint256 executionsLength = executions.length;
                  if (executionsLength == 0) {
                    revert("No orders to execute");
                  }
                  for (uint8 i = 0; i < executionsLength; i++) {
                      assembly {
                          let memPointer := mload(0x40)
                          let order_location := calldataload(add(executions.offset, mul(i, 0x20)))
                          let order_pointer := add(executions.offset, order_location)
                          let size
                          switch eq(add(i, 0x01), executionsLength)
                          case 1 {
                              size := sub(calldatasize(), order_pointer)
                          }
                          default {
                              let next_order_location := calldataload(add(executions.offset, mul(add(i, 0x01), 0x20)))
                              let next_order_pointer := add(executions.offset, next_order_location)
                              size := sub(next_order_pointer, order_pointer)
                          }
                          mstore(memPointer, 0xe04d94ae00000000000000000000000000000000000000000000000000000000) // _execute
                          calldatacopy(add(0x04, memPointer), order_pointer, size)
                          // must be put in separate transaction to bypass failed executions
                          // must be put in delegatecall to maintain the authorization from the caller
                          let result := delegatecall(gas(), address(), memPointer, add(size, 0x04), 0, 0)
                      }
                  }
                  _returnDust();
              }
              /**
               * @dev Match two orders, ensuring validity of the match, and execute all associated state transitions. Must be called internally.
               * @param sell Sell input
               * @param buy Buy input
               */
              function _execute(Input calldata sell, Input calldata buy)
                  public
                  payable
                  internalCall
                  reentrancyGuard // move re-entrancy check for clarity
              {
                  require(sell.order.side == Side.Sell);
                  bytes32 sellHash = _hashOrder(sell.order, nonces[sell.order.trader]);
                  bytes32 buyHash = _hashOrder(buy.order, nonces[buy.order.trader]);
                  require(_validateOrderParameters(sell.order, sellHash), "Sell has invalid parameters");
                  require(_validateOrderParameters(buy.order, buyHash), "Buy has invalid parameters");
                  require(_validateSignatures(sell, sellHash), "Sell failed authorization");
                  require(_validateSignatures(buy, buyHash), "Buy failed authorization");
                  (uint256 price, uint256 tokenId, uint256 amount, AssetType assetType) = _canMatchOrders(sell.order, buy.order);
                  /* Mark orders as filled. */
                  cancelledOrFilled[sellHash] = true;
                  cancelledOrFilled[buyHash] = true;
                  _executeFundsTransfer(
                      sell.order.trader,
                      buy.order.trader,
                      sell.order.paymentToken,
                      sell.order.fees,
                      buy.order.fees,
                      price
                  );
                  _executeTokenTransfer(
                      sell.order.collection,
                      sell.order.trader,
                      buy.order.trader,
                      tokenId,
                      amount,
                      assetType
                  );
                  emit OrdersMatched(
                      sell.order.listingTime <= buy.order.listingTime ? sell.order.trader : buy.order.trader,
                      sell.order.listingTime > buy.order.listingTime ? sell.order.trader : buy.order.trader,
                      sell.order,
                      sellHash,
                      buy.order,
                      buyHash
                  );
              }
              /**
               * @dev Cancel an order, preventing it from being matched. Must be called by the trader of the order
               * @param order Order to cancel
               */
              function cancelOrder(Order calldata order) public {
                  /* Assert sender is authorized to cancel order. */
                  require(msg.sender == order.trader, "Not sent by trader");
                  bytes32 hash = _hashOrder(order, nonces[order.trader]);
                  require(!cancelledOrFilled[hash], "Order cancelled or filled");
                  /* Mark order as cancelled, preventing it from being matched. */
                  cancelledOrFilled[hash] = true;
                  emit OrderCancelled(hash);
              }
              /**
               * @dev Cancel multiple orders
               * @param orders Orders to cancel
               */
              function cancelOrders(Order[] calldata orders) external {
                  for (uint8 i = 0; i < orders.length; i++) {
                      cancelOrder(orders[i]);
                  }
              }
              /**
               * @dev Cancel all current orders for a user, preventing them from being matched. Must be called by the trader of the order
               */
              function incrementNonce() external {
                  nonces[msg.sender] += 1;
                  emit NonceIncremented(msg.sender, nonces[msg.sender]);
              }
              /* Setters */
              function setExecutionDelegate(IExecutionDelegate _executionDelegate)
                  external
                  onlyOwner
              {
                  require(address(_executionDelegate) != address(0), "Address cannot be zero");
                  executionDelegate = _executionDelegate;
                  emit NewExecutionDelegate(executionDelegate);
              }
              function setPolicyManager(IPolicyManager _policyManager)
                  external
                  onlyOwner
              {
                  require(address(_policyManager) != address(0), "Address cannot be zero");
                  policyManager = _policyManager;
                  emit NewPolicyManager(policyManager);
              }
              function setOracle(address _oracle)
                  external
                  onlyOwner
              {
                  require(_oracle != address(0), "Address cannot be zero");
                  oracle = _oracle;
                  emit NewOracle(oracle);
              }
              function setBlockRange(uint256 _blockRange)
                  external
                  onlyOwner
              {
                  blockRange = _blockRange;
                  emit NewBlockRange(blockRange);
              }
              function setGovernor(address _governor)
                  external
                  onlyOwner
              {
                  governor = _governor;
                  emit NewGovernor(governor);
              }
              function setFeeRate(uint256 _feeRate)
                  external
              {
                  require(msg.sender == governor, "Fee rate can only be set by governor");
                  require(_feeRate <= MAX_FEE_RATE, "Fee cannot be more than 2.5%");
                  feeRate = _feeRate;
                  emit NewFeeRate(feeRate);
              }
              function setFeeRecipient(address _feeRecipient)
                  external
                  onlyOwner
              {
                  feeRecipient = _feeRecipient;
                  emit NewFeeRecipient(feeRecipient);
              }
              /* Internal Functions */
              /**
               * @dev Verify the validity of the order parameters
               * @param order order
               * @param orderHash hash of order
               */
              function _validateOrderParameters(Order calldata order, bytes32 orderHash)
                  internal
                  view
                  returns (bool)
              {
                  return (
                      /* Order must have a trader. */
                      (order.trader != address(0)) &&
                      /* Order must not be cancelled or filled. */
                      (!cancelledOrFilled[orderHash]) &&
                      /* Order must be settleable. */
                      (order.listingTime < block.timestamp) &&
                      (block.timestamp < order.expirationTime)
                  );
              }
              /**
               * @dev Verify the validity of the signatures
               * @param order order
               * @param orderHash hash of order
               */
              function _validateSignatures(Input calldata order, bytes32 orderHash)
                  internal
                  view
                  returns (bool)
              {
                  if (order.order.extraParams.length > 0 && order.order.extraParams[0] == 0x01) {
                      /* Check oracle authorization. */
                      require(block.number - order.blockNumber < blockRange, "Signed block number out of range");
                      if (
                          !_validateOracleAuthorization(
                              orderHash,
                              order.signatureVersion,
                              order.extraSignature,
                              order.blockNumber
                          )
                      ) {
                          return false;
                      }
                  }
                  if (order.order.trader == msg.sender) {
                    return true;
                  }
                  /* Check user authorization. */
                  if (
                      !_validateUserAuthorization(
                          orderHash,
                          order.order.trader,
                          order.v,
                          order.r,
                          order.s,
                          order.signatureVersion,
                          order.extraSignature
                      )
                  ) {
                      return false;
                  }
                  return true;
              }
              /**
               * @dev Verify the validity of the user signature
               * @param orderHash hash of the order
               * @param trader order trader who should be the signer
               * @param v v
               * @param r r
               * @param s s
               * @param signatureVersion signature version
               * @param extraSignature packed merkle path
               */
              function _validateUserAuthorization(
                  bytes32 orderHash,
                  address trader,
                  uint8 v,
                  bytes32 r,
                  bytes32 s,
                  SignatureVersion signatureVersion,
                  bytes calldata extraSignature
              ) internal view returns (bool) {
                  bytes32 hashToSign;
                  if (signatureVersion == SignatureVersion.Single) {
                      /* Single-listing authentication: Order signed by trader */
                      hashToSign = _hashToSign(orderHash);
                  } else if (signatureVersion == SignatureVersion.Bulk) {
                      /* Bulk-listing authentication: Merkle root of orders signed by trader */
                      (bytes32[] memory merklePath) = abi.decode(extraSignature, (bytes32[]));
                      bytes32 computedRoot = MerkleVerifier._computeRoot(orderHash, merklePath);
                      hashToSign = _hashToSignRoot(computedRoot);
                  }
                  return _verify(trader, hashToSign, v, r, s);
              }
              /**
               * @dev Verify the validity of oracle signature
               * @param orderHash hash of the order
               * @param signatureVersion signature version
               * @param extraSignature packed oracle signature
               * @param blockNumber block number used in oracle signature
               */
              function _validateOracleAuthorization(
                  bytes32 orderHash,
                  SignatureVersion signatureVersion,
                  bytes calldata extraSignature,
                  uint256 blockNumber
              ) internal view returns (bool) {
                  bytes32 oracleHash = _hashToSignOracle(orderHash, blockNumber);
                  uint8 v; bytes32 r; bytes32 s;
                  if (signatureVersion == SignatureVersion.Single) {
                      assembly {
                          v := calldataload(extraSignature.offset)
                          r := calldataload(add(extraSignature.offset, 0x20))
                          s := calldataload(add(extraSignature.offset, 0x40))
                      }
                      /*
                      REFERENCE
                      (v, r, s) = abi.decode(extraSignature, (uint8, bytes32, bytes32));
                      */
                  } else if (signatureVersion == SignatureVersion.Bulk) {
                      /* If the signature was a bulk listing the merkle path must be unpacked before the oracle signature. */
                      assembly {
                          v := calldataload(add(extraSignature.offset, 0x20))
                          r := calldataload(add(extraSignature.offset, 0x40))
                          s := calldataload(add(extraSignature.offset, 0x60))
                      }
                      /*
                      REFERENCE
                      uint8 _v, bytes32 _r, bytes32 _s;
                      (bytes32[] memory merklePath, uint8 _v, bytes32 _r, bytes32 _s) = abi.decode(extraSignature, (bytes32[], uint8, bytes32, bytes32));
                      v = _v; r = _r; s = _s;
                      */
                  }
                  return _verify(oracle, oracleHash, v, r, s);
              }
              /**
               * @dev Verify ECDSA signature
               * @param signer Expected signer
               * @param digest Signature preimage
               * @param v v
               * @param r r
               * @param s s
               */
              function _verify(
                  address signer,
                  bytes32 digest,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal pure returns (bool) {
                  require(v == 27 || v == 28, "Invalid v parameter");
                  address recoveredSigner = ecrecover(digest, v, r, s);
                  if (recoveredSigner == address(0)) {
                    return false;
                  } else {
                    return signer == recoveredSigner;
                  }
              }
              /**
               * @dev Call the matching policy to check orders can be matched and get execution parameters
               * @param sell sell order
               * @param buy buy order
               */
              function _canMatchOrders(Order calldata sell, Order calldata buy)
                  internal
                  view
                  returns (uint256 price, uint256 tokenId, uint256 amount, AssetType assetType)
              {
                  bool canMatch;
                  if (sell.listingTime <= buy.listingTime) {
                      /* Seller is maker. */
                      require(policyManager.isPolicyWhitelisted(sell.matchingPolicy), "Policy is not whitelisted");
                      (canMatch, price, tokenId, amount, assetType) = IMatchingPolicy(sell.matchingPolicy).canMatchMakerAsk(sell, buy);
                  } else {
                      /* Buyer is maker. */
                      require(policyManager.isPolicyWhitelisted(buy.matchingPolicy), "Policy is not whitelisted");
                      (canMatch, price, tokenId, amount, assetType) = IMatchingPolicy(buy.matchingPolicy).canMatchMakerBid(buy, sell);
                  }
                  require(canMatch, "Orders cannot be matched");
                  return (price, tokenId, amount, assetType);
              }
              /**
               * @dev Execute all ERC20 token / ETH transfers associated with an order match (fees and buyer => seller transfer)
               * @param seller seller
               * @param buyer buyer
               * @param paymentToken payment token
               * @param sellerFees seller fees
               * @param buyerFees buyer fees
               * @param price price
               */
              function _executeFundsTransfer(
                  address seller,
                  address buyer,
                  address paymentToken,
                  Fee[] calldata sellerFees,
                  Fee[] calldata buyerFees,
                  uint256 price
              ) internal {
                  if (paymentToken == address(0)) {
                      require(msg.sender == buyer, "Cannot use ETH");
                      require(remainingETH >= price, "Insufficient value");
                      remainingETH -= price;
                  }
                  /* Take fee. */
                  uint256 sellerFeesPaid = _transferFees(sellerFees, paymentToken, buyer, price, true);
                  uint256 buyerFeesPaid = _transferFees(buyerFees, paymentToken, buyer, price, false);
                  if (paymentToken == address(0)) {
                    /* Need to account for buyer fees paid on top of the price. */
                    remainingETH -= buyerFeesPaid;
                  }
                  /* Transfer remainder to seller. */
                  _transferTo(paymentToken, buyer, seller, price - sellerFeesPaid);
              }
              /**
               * @dev Charge a fee in ETH or WETH
               * @param fees fees to distribute
               * @param paymentToken address of token to pay in
               * @param from address to charge fees
               * @param price price of token
               * @return total fees paid
               */
              function _transferFees(
                  Fee[] calldata fees,
                  address paymentToken,
                  address from,
                  uint256 price,
                  bool protocolFee
              ) internal returns (uint256) {
                  uint256 totalFee = 0;
                  /* Take protocol fee if enabled. */
                  if (feeRate > 0 && protocolFee) {
                      uint256 fee = (price * feeRate) / INVERSE_BASIS_POINT;
                      _transferTo(paymentToken, from, feeRecipient, fee);
                      totalFee += fee;
                  }
                  /* Take order fees. */
                  for (uint8 i = 0; i < fees.length; i++) {
                      uint256 fee = (price * fees[i].rate) / INVERSE_BASIS_POINT;
                      _transferTo(paymentToken, from, fees[i].recipient, fee);
                      totalFee += fee;
                  }
                  require(totalFee <= price, "Fees are more than the price");
                  return totalFee;
              }
              /**
               * @dev Transfer amount in ETH or WETH
               * @param paymentToken address of token to pay in
               * @param from token sender
               * @param to token recipient
               * @param amount amount to transfer
               */
              function _transferTo(
                  address paymentToken,
                  address from,
                  address to,
                  uint256 amount
              ) internal {
                  if (amount == 0) {
                      return;
                  }
                  if (paymentToken == address(0)) {
                      /* Transfer funds in ETH. */
                      require(to != address(0), "Transfer to zero address");
                      (bool success,) = payable(to).call{value: amount}("");
                      require(success, "ETH transfer failed");
                  } else if (paymentToken == POOL) {
                      /* Transfer Pool funds. */
                      bool success = IBlurPool(POOL).transferFrom(from, to, amount);
                      require(success, "Pool transfer failed");
                  } else if (paymentToken == WETH) {
                      /* Transfer funds in WETH. */
                      executionDelegate.transferERC20(WETH, from, to, amount);
                  } else {
                      revert("Invalid payment token");
                  }
              }
              /**
               * @dev Execute call through delegate proxy
               * @param collection collection contract address
               * @param from seller address
               * @param to buyer address
               * @param tokenId tokenId
               * @param assetType asset type of the token
               */
              function _executeTokenTransfer(
                  address collection,
                  address from,
                  address to,
                  uint256 tokenId,
                  uint256 amount,
                  AssetType assetType
              ) internal {
                  /* Call execution delegate. */
                  if (assetType == AssetType.ERC721) {
                      executionDelegate.transferERC721(collection, from, to, tokenId);
                  } else if (assetType == AssetType.ERC1155) {
                      executionDelegate.transferERC1155(collection, from, to, tokenId, amount);
                  }
              }
              /**
               * @dev Return remaining ETH sent to bulkExecute or execute
               */
              function _returnDust() private {
                  uint256 _remainingETH = remainingETH;
                  assembly {
                      if gt(_remainingETH, 0) {
                          let callStatus := call(
                              gas(),
                              caller(),
                              _remainingETH,
                              0,
                              0,
                              0,
                              0
                          )
                          if iszero(callStatus) {
                            revert(0, 0)
                          }
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
          pragma solidity ^0.8.2;
          import "../../utils/AddressUpgradeable.sol";
          /**
           * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
           * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
           * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
           * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
           *
           * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
           * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
           * case an upgrade adds a module that needs to be initialized.
           *
           * For example:
           *
           * [.hljs-theme-light.nopadding]
           * ```
           * contract MyToken is ERC20Upgradeable {
           *     function initialize() initializer public {
           *         __ERC20_init("MyToken", "MTK");
           *     }
           * }
           * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
           *     function initializeV2() reinitializer(2) public {
           *         __ERC20Permit_init("MyToken");
           *     }
           * }
           * ```
           *
           * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
           * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
           *
           * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
           * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
           *
           * [CAUTION]
           * ====
           * Avoid leaving a contract uninitialized.
           *
           * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
           * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
           * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
           *
           * [.hljs-theme-light.nopadding]
           * ```
           * /// @custom:oz-upgrades-unsafe-allow constructor
           * constructor() {
           *     _disableInitializers();
           * }
           * ```
           * ====
           */
          abstract contract Initializable {
              /**
               * @dev Indicates that the contract has been initialized.
               * @custom:oz-retyped-from bool
               */
              uint8 private _initialized;
              /**
               * @dev Indicates that the contract is in the process of being initialized.
               */
              bool private _initializing;
              /**
               * @dev Triggered when the contract has been initialized or reinitialized.
               */
              event Initialized(uint8 version);
              /**
               * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
               * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
               */
              modifier initializer() {
                  bool isTopLevelCall = !_initializing;
                  require(
                      (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                      "Initializable: contract is already initialized"
                  );
                  _initialized = 1;
                  if (isTopLevelCall) {
                      _initializing = true;
                  }
                  _;
                  if (isTopLevelCall) {
                      _initializing = false;
                      emit Initialized(1);
                  }
              }
              /**
               * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
               * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
               * used to initialize parent contracts.
               *
               * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
               * initialization step. This is essential to configure modules that are added through upgrades and that require
               * initialization.
               *
               * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
               * a contract, executing them in the right order is up to the developer or operator.
               */
              modifier reinitializer(uint8 version) {
                  require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                  _initialized = version;
                  _initializing = true;
                  _;
                  _initializing = false;
                  emit Initialized(version);
              }
              /**
               * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
               * {initializer} and {reinitializer} modifiers, directly or indirectly.
               */
              modifier onlyInitializing() {
                  require(_initializing, "Initializable: contract is not initializing");
                  _;
              }
              /**
               * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
               * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
               * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
               * through proxies.
               */
              function _disableInitializers() internal virtual {
                  require(!_initializing, "Initializable: contract is initializing");
                  if (_initialized < type(uint8).max) {
                      _initialized = type(uint8).max;
                      emit Initialized(type(uint8).max);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/utils/UUPSUpgradeable.sol)
          pragma solidity ^0.8.0;
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
          import "./Initializable.sol";
          /**
           * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
           * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
           *
           * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
           * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
           * `UUPSUpgradeable` with a custom implementation of upgrades.
           *
           * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
           *
           * _Available since v4.1._
           */
          abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
              function __UUPSUpgradeable_init() internal onlyInitializing {
              }
              function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
              }
              /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
              address private immutable __self = address(this);
              /**
               * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
               * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
               * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
               * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
               * fail.
               */
              modifier onlyProxy() {
                  require(address(this) != __self, "Function must be called through delegatecall");
                  require(_getImplementation() == __self, "Function must be called through active proxy");
                  _;
              }
              /**
               * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
               * callable on the implementing contract but not through proxies.
               */
              modifier notDelegated() {
                  require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
                  _;
              }
              /**
               * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
               * implementation. It is used to validate that the this implementation remains valid after an upgrade.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
               */
              function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
                  return _IMPLEMENTATION_SLOT;
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeTo(address newImplementation) external virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
               * encoded in `data`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, data, true);
              }
              /**
               * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
               * {upgradeTo} and {upgradeToAndCall}.
               *
               * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
               *
               * ```solidity
               * function _authorizeUpgrade(address) internal override onlyOwner {}
               * ```
               */
              function _authorizeUpgrade(address newImplementation) internal virtual;
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
          pragma solidity ^0.8.0;
          import "../utils/ContextUpgradeable.sol";
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              function __Ownable_init() internal onlyInitializing {
                  __Ownable_init_unchained();
              }
              function __Ownable_init_unchained() internal onlyInitializing {
                  _transferOwnership(_msgSender());
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  _checkOwner();
                  _;
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if the sender is not the owner.
               */
              function _checkOwner() internal view virtual {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions anymore. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby removing any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  _transferOwnership(address(0));
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  _transferOwnership(newOwner);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Internal function without access restriction.
               */
              function _transferOwnership(address newOwner) internal virtual {
                  address oldOwner = _owner;
                  _owner = newOwner;
                  emit OwnershipTransferred(oldOwner, newOwner);
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          /**
           * @title ReentrancyGuarded
           * @dev Protections for reentrancy attacks
           */
          contract ReentrancyGuarded {
              bool private reentrancyLock = false;
              /* Prevent a contract function from being reentrant-called. */
              modifier reentrancyGuard {
                  require(!reentrancyLock, "Reentrancy detected");
                  reentrancyLock = true;
                  _;
                  reentrancyLock = false;
              }
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import {Order, Fee} from "./OrderStructs.sol";
          /**
           * @title EIP712
           * @dev Contains all of the order hashing functions for EIP712 compliant signatures
           */
          contract EIP712 {
              struct EIP712Domain {
                  string  name;
                  string  version;
                  uint256 chainId;
                  address verifyingContract;
              }
              /* Order typehash for EIP 712 compatibility. */
              bytes32 constant public FEE_TYPEHASH = keccak256(
                  "Fee(uint16 rate,address recipient)"
              );
              bytes32 constant public ORDER_TYPEHASH = keccak256(
                  "Order(address trader,uint8 side,address matchingPolicy,address collection,uint256 tokenId,uint256 amount,address paymentToken,uint256 price,uint256 listingTime,uint256 expirationTime,Fee[] fees,uint256 salt,bytes extraParams,uint256 nonce)Fee(uint16 rate,address recipient)"
              );
              bytes32 constant public ORACLE_ORDER_TYPEHASH = keccak256(
                  "OracleOrder(Order order,uint256 blockNumber)Fee(uint16 rate,address recipient)Order(address trader,uint8 side,address matchingPolicy,address collection,uint256 tokenId,uint256 amount,address paymentToken,uint256 price,uint256 listingTime,uint256 expirationTime,Fee[] fees,uint256 salt,bytes extraParams,uint256 nonce)"
              );
              bytes32 constant public ROOT_TYPEHASH = keccak256(
                  "Root(bytes32 root)"
              );
              bytes32 constant EIP712DOMAIN_TYPEHASH = keccak256(
                  "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
              );
              bytes32 DOMAIN_SEPARATOR;
              function _hashDomain(EIP712Domain memory eip712Domain)
                  internal
                  pure
                  returns (bytes32)
              {
                  return keccak256(
                      abi.encode(
                          EIP712DOMAIN_TYPEHASH,
                          keccak256(bytes(eip712Domain.name)),
                          keccak256(bytes(eip712Domain.version)),
                          eip712Domain.chainId,
                          eip712Domain.verifyingContract
                      )
                  );
              }
              function _hashFee(Fee calldata fee)
                  internal 
                  pure
                  returns (bytes32)
              {
                  return keccak256(
                      abi.encode(
                          FEE_TYPEHASH,
                          fee.rate,
                          fee.recipient
                      )
                  );
              }
              function _packFees(Fee[] calldata fees)
                  internal
                  pure
                  returns (bytes32)
              {
                  bytes32[] memory feeHashes = new bytes32[](
                      fees.length
                  );
                  for (uint256 i = 0; i < fees.length; i++) {
                      feeHashes[i] = _hashFee(fees[i]);
                  }
                  return keccak256(abi.encodePacked(feeHashes));
              }
              function _hashOrder(Order calldata order, uint256 nonce)
                  internal
                  pure
                  returns (bytes32)
              {
                  return keccak256(
                      bytes.concat(
                          abi.encode(
                                ORDER_TYPEHASH,
                                order.trader,
                                order.side,
                                order.matchingPolicy,
                                order.collection,
                                order.tokenId,
                                order.amount,
                                order.paymentToken,
                                order.price,
                                order.listingTime,
                                order.expirationTime,
                                _packFees(order.fees),
                                order.salt,
                                keccak256(order.extraParams)
                          ),
                          abi.encode(nonce)
                      )
                  );
              }
              function _hashToSign(bytes32 orderHash)
                  internal
                  view
                  returns (bytes32 hash)
              {
                  return keccak256(abi.encodePacked(
                      "\\x19\\x01",
                      DOMAIN_SEPARATOR,
                      orderHash
                  ));
              }
              function _hashToSignRoot(bytes32 root)
                  internal
                  view
                  returns (bytes32 hash)
              {
                  return keccak256(abi.encodePacked(
                      "\\x19\\x01",
                      DOMAIN_SEPARATOR,
                      keccak256(abi.encode(
                          ROOT_TYPEHASH,
                          root
                      ))
                  ));
              }
              function _hashToSignOracle(bytes32 orderHash, uint256 blockNumber)
                  internal
                  view
                  returns (bytes32 hash)
              {
                  return keccak256(abi.encodePacked(
                      "\\x19\\x01",
                      DOMAIN_SEPARATOR,
                      keccak256(abi.encode(
                          ORACLE_ORDER_TYPEHASH,
                          orderHash,
                          blockNumber
                      ))
                  ));
              }
              uint256[44] private __gap;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          /**
           * @title MerkleVerifier
           * @dev Utility functions for Merkle tree computations
           */
          library MerkleVerifier {
              error InvalidProof();
              /**
               * @dev Verify the merkle proof
               * @param leaf leaf
               * @param root root
               * @param proof proof
               */
              function _verifyProof(
                  bytes32 leaf,
                  bytes32 root,
                  bytes32[] memory proof
              ) public pure {
                  bytes32 computedRoot = _computeRoot(leaf, proof);
                  if (computedRoot != root) {
                      revert InvalidProof();
                  }
              }
              /**
               * @dev Compute the merkle root
               * @param leaf leaf
               * @param proof proof
               */
              function _computeRoot(
                  bytes32 leaf,
                  bytes32[] memory proof
              ) public pure returns (bytes32) {
                  bytes32 computedHash = leaf;
                  for (uint256 i = 0; i < proof.length; i++) {
                      bytes32 proofElement = proof[i];
                      computedHash = _hashPair(computedHash, proofElement);
                  }
                  return computedHash;
              }
              function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32) {
                  return a < b ? _efficientHash(a, b) : _efficientHash(b, a);
              }
              function _efficientHash(
                  bytes32 a,
                  bytes32 b
              ) private pure returns (bytes32 value) {
                  assembly {
                      mstore(0x00, a)
                      mstore(0x20, b)
                      value := keccak256(0x00, 0x40)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import {Input, Order} from "../lib/OrderStructs.sol";
          import "./IExecutionDelegate.sol";
          import "./IPolicyManager.sol";
          interface IBlurExchange {
              function nonces(address) external view returns (uint256);
              function close() external;
              function initialize(
                  IExecutionDelegate _executionDelegate,
                  IPolicyManager _policyManager,
                  address _oracle,
                  uint _blockRange
              ) external;
              function setExecutionDelegate(IExecutionDelegate _executionDelegate) external;
              function setPolicyManager(IPolicyManager _policyManager) external;
              function setOracle(address _oracle) external;
              function setBlockRange(uint256 _blockRange) external;
              function cancelOrder(Order calldata order) external;
              function cancelOrders(Order[] calldata orders) external;
              function incrementNonce() external;
              function execute(Input calldata sell, Input calldata buy)
                  external
                  payable;
          }
          pragma solidity ^0.8.17;
          interface IBlurPool {
              event Transfer(address indexed from, address indexed to, uint256 amount);
              function totalSupply() external view returns (uint256);
              function balanceOf(address user) external view returns (uint256);
              function deposit() external payable;
              function withdraw(uint256) external;
              function transferFrom(address from, address to, uint256 amount)
                  external
                  returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          interface IExecutionDelegate {
              function approveContract(address _contract) external;
              function denyContract(address _contract) external;
              function revokeApproval() external;
              function grantApproval() external;
              function transferERC721Unsafe(address collection, address from, address to, uint256 tokenId) external;
              function transferERC721(address collection, address from, address to, uint256 tokenId) external;
              function transferERC1155(address collection, address from, address to, uint256 tokenId, uint256 amount) external;
              function transferERC20(address token, address from, address to, uint256 amount) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          interface IPolicyManager {
              function addPolicy(address policy) external;
              function removePolicy(address policy) external;
              function isPolicyWhitelisted(address policy) external view returns (bool);
              function viewWhitelistedPolicies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
              function viewCountWhitelistedPolicies() external view returns (uint256);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import {Order, AssetType} from "../lib/OrderStructs.sol";
          interface IMatchingPolicy {
              function canMatchMakerAsk(Order calldata makerAsk, Order calldata takerBid)
                  external
                  view
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  );
              function canMatchMakerBid(Order calldata makerBid, Order calldata takerAsk)
                  external
                  view
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  );
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          enum Side { Buy, Sell }
          enum SignatureVersion { Single, Bulk }
          enum AssetType { ERC721, ERC1155 }
          struct Fee {
              uint16 rate;
              address payable recipient;
          }
          struct Order {
              address trader;
              Side side;
              address matchingPolicy;
              address collection;
              uint256 tokenId;
              uint256 amount;
              address paymentToken;
              uint256 price;
              uint256 listingTime;
              /* Order expiration timestamp - 0 for oracle cancellations. */
              uint256 expirationTime;
              Fee[] fees;
              uint256 salt;
              bytes extraParams;
          }
          struct Input {
              Order order;
              uint8 v;
              bytes32 r;
              bytes32 s;
              bytes extraSignature;
              SignatureVersion signatureVersion;
              uint256 blockNumber;
          }
          struct Execution {
            Input sell;
            Input buy;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
          pragma solidity ^0.8.1;
          /**
           * @dev Collection of functions related to the address type
           */
          library AddressUpgradeable {
              /**
               * @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
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
                  return account.code.length > 0;
              }
              /**
               * @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, "Address: insufficient balance");
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @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:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCall(target, data, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  require(isContract(target), "Address: call to non-contract");
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  require(isContract(target), "Address: static call to non-contract");
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) 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
                          /// @solidity memory-safe-assembly
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
           * proxy whose upgrades are fully controlled by the current implementation.
           */
          interface IERC1822ProxiableUpgradeable {
              /**
               * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
               * address.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy.
               */
              function proxiableUUID() external view returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
          pragma solidity ^0.8.2;
          import "../beacon/IBeaconUpgradeable.sol";
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../../utils/AddressUpgradeable.sol";
          import "../../utils/StorageSlotUpgradeable.sol";
          import "../utils/Initializable.sol";
          /**
           * @dev This abstract contract provides getters and event emitting update functions for
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
           *
           * _Available since v4.1._
           *
           * @custom:oz-upgrades-unsafe-allow delegatecall
           */
          abstract contract ERC1967UpgradeUpgradeable is Initializable {
              function __ERC1967Upgrade_init() internal onlyInitializing {
              }
              function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
              }
              // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
              bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
              /**
               * @dev Storage slot with the address of the current implementation.
               * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
              /**
               * @dev Emitted when the implementation is upgraded.
               */
              event Upgraded(address indexed implementation);
              /**
               * @dev Returns the current implementation address.
               */
              function _getImplementation() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 implementation slot.
               */
              function _setImplementation(address newImplementation) private {
                  require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                  StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
              }
              /**
               * @dev Perform implementation upgrade
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
              /**
               * @dev Perform implementation upgrade with additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCall(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _upgradeTo(newImplementation);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(newImplementation, data);
                  }
              }
              /**
               * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCallUUPS(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  // Upgrades from old implementations will perform a rollback test. This test requires the new
                  // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                  // this special case will break upgrade paths from old UUPS implementation to new ones.
                  if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                      _setImplementation(newImplementation);
                  } else {
                      try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                          require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                      } catch {
                          revert("ERC1967Upgrade: new implementation is not UUPS");
                      }
                      _upgradeToAndCall(newImplementation, data, forceCall);
                  }
              }
              /**
               * @dev Storage slot with the admin of the contract.
               * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
              /**
               * @dev Emitted when the admin account has changed.
               */
              event AdminChanged(address previousAdmin, address newAdmin);
              /**
               * @dev Returns the current admin.
               */
              function _getAdmin() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 admin slot.
               */
              function _setAdmin(address newAdmin) private {
                  require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                  StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
              }
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               */
              function _changeAdmin(address newAdmin) internal {
                  emit AdminChanged(_getAdmin(), newAdmin);
                  _setAdmin(newAdmin);
              }
              /**
               * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
               * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
               */
              bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
              /**
               * @dev Emitted when the beacon is upgraded.
               */
              event BeaconUpgraded(address indexed beacon);
              /**
               * @dev Returns the current beacon.
               */
              function _getBeacon() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
              }
              /**
               * @dev Stores a new beacon in the EIP1967 beacon slot.
               */
              function _setBeacon(address newBeacon) private {
                  require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                  require(
                      AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                      "ERC1967: beacon implementation is not a contract"
                  );
                  StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
              }
              /**
               * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
               * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
               *
               * Emits a {BeaconUpgraded} event.
               */
              function _upgradeBeaconToAndCall(
                  address newBeacon,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _setBeacon(newBeacon);
                  emit BeaconUpgraded(newBeacon);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
                  }
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
                  require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev This is the interface that {BeaconProxy} expects of its beacon.
           */
          interface IBeaconUpgradeable {
              /**
               * @dev Must return an address that can be used as a delegate call target.
               *
               * {BeaconProxy} will check that this address is a contract.
               */
              function implementation() external view returns (address);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Library for reading and writing primitive types to specific storage slots.
           *
           * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
           * This library helps with reading and writing to such slots without the need for inline assembly.
           *
           * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
           *
           * Example usage to set ERC1967 implementation slot:
           * ```
           * contract ERC1967 {
           *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
           *
           *     function _getImplementation() internal view returns (address) {
           *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
           *     }
           *
           *     function _setImplementation(address newImplementation) internal {
           *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
           *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
           *     }
           * }
           * ```
           *
           * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
           */
          library StorageSlotUpgradeable {
              struct AddressSlot {
                  address value;
              }
              struct BooleanSlot {
                  bool value;
              }
              struct Bytes32Slot {
                  bytes32 value;
              }
              struct Uint256Slot {
                  uint256 value;
              }
              /**
               * @dev Returns an `AddressSlot` with member `value` located at `slot`.
               */
              function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
               */
              function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
               */
              function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
               */
              function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract ContextUpgradeable is Initializable {
              function __Context_init() internal onlyInitializing {
              }
              function __Context_init_unchained() internal onlyInitializing {
              }
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          

          File 4 of 5: StandardPolicyERC721
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import {Order, AssetType} from "../lib/OrderStructs.sol";
          import {IMatchingPolicy} from "../interfaces/IMatchingPolicy.sol";
          /**
           * @title StandardPolicyERC721
           * @dev Policy for matching orders at a fixed price for a specific ERC721 tokenId (requires oracle authorization on both orders)
           */
          contract StandardPolicyERC721 is IMatchingPolicy {
              function canMatchMakerAsk(Order calldata makerAsk, Order calldata takerBid)
                  external
                  pure
                  override
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  )
              {
                  return (
                      (makerAsk.side != takerBid.side) &&
                      (makerAsk.paymentToken == takerBid.paymentToken) &&
                      (makerAsk.collection == takerBid.collection) &&
                      (makerAsk.tokenId == takerBid.tokenId) &&
                      (makerAsk.extraParams.length > 0 && makerAsk.extraParams[0] == "\\x01") &&
                      (takerBid.extraParams.length > 0 && takerBid.extraParams[0] == "\\x01") &&
                      (makerAsk.amount == 1) &&
                      (takerBid.amount == 1) &&
                      (makerAsk.matchingPolicy == takerBid.matchingPolicy) &&
                      (makerAsk.price == takerBid.price),
                      makerAsk.price,
                      makerAsk.tokenId,
                      1,
                      AssetType.ERC721
                  );
              }
              function canMatchMakerBid(Order calldata makerBid, Order calldata takerAsk)
                  external
                  pure
                  override
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  )
              {
                  return (
                      (makerBid.side != takerAsk.side) &&
                      (makerBid.paymentToken == takerAsk.paymentToken) &&
                      (makerBid.collection == takerAsk.collection) &&
                      (makerBid.tokenId == takerAsk.tokenId) &&
                      (makerBid.extraParams.length > 0 && makerBid.extraParams[0] == "\\x01") &&
                      (takerAsk.extraParams.length > 0 && takerAsk.extraParams[0] == "\\x01") &&
                      (makerBid.amount == 1) &&
                      (takerAsk.amount == 1) &&
                      (makerBid.matchingPolicy == takerAsk.matchingPolicy) &&
                      (makerBid.price == takerAsk.price),
                      makerBid.price,
                      makerBid.tokenId,
                      1,
                      AssetType.ERC721
                  );
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          enum Side { Buy, Sell }
          enum SignatureVersion { Single, Bulk }
          enum AssetType { ERC721, ERC1155 }
          struct Fee {
              uint16 rate;
              address payable recipient;
          }
          struct Order {
              address trader;
              Side side;
              address matchingPolicy;
              address collection;
              uint256 tokenId;
              uint256 amount;
              address paymentToken;
              uint256 price;
              uint256 listingTime;
              /* Order expiration timestamp - 0 for oracle cancellations. */
              uint256 expirationTime;
              Fee[] fees;
              uint256 salt;
              bytes extraParams;
          }
          struct Input {
              Order order;
              uint8 v;
              bytes32 r;
              bytes32 s;
              bytes extraSignature;
              SignatureVersion signatureVersion;
              uint256 blockNumber;
          }
          struct Execution {
            Input sell;
            Input buy;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.17;
          import {Order, AssetType} from "../lib/OrderStructs.sol";
          interface IMatchingPolicy {
              function canMatchMakerAsk(Order calldata makerAsk, Order calldata takerBid)
                  external
                  view
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  );
              function canMatchMakerBid(Order calldata makerBid, Order calldata takerAsk)
                  external
                  view
                  returns (
                      bool,
                      uint256,
                      uint256,
                      uint256,
                      AssetType
                  );
          }
          

          File 5 of 5: OperatorFilterRegistry
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
          pragma solidity ^0.8.0;
          import "../utils/Context.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract Ownable is Context {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              constructor() {
                  _transferOwnership(_msgSender());
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  _checkOwner();
                  _;
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if the sender is not the owner.
               */
              function _checkOwner() internal view virtual {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions anymore. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby removing any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  _transferOwnership(address(0));
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  _transferOwnership(newOwner);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Internal function without access restriction.
               */
              function _transferOwnership(address newOwner) internal virtual {
                  address oldOwner = _owner;
                  _owner = newOwner;
                  emit OwnershipTransferred(oldOwner, newOwner);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (utils/structs/EnumerableSet.sol)
          // This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.
          pragma solidity ^0.8.0;
          /**
           * @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.
           *
           * [WARNING]
           * ====
           * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure
           * unusable.
           * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
           *
           * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an
           * array of EnumerableSet.
           * ====
           */
          library EnumerableSet {
              // To implement this library for multiple types with as little code
              // repetition as possible, we write it in terms of a generic Set type with
              // bytes32 values.
              // The Set implementation uses private functions, and user-facing
              // implementations (such as AddressSet) are just wrappers around the
              // underlying Set.
              // This means that we can only create new EnumerableSets for types that fit
              // in bytes32.
              struct Set {
                  // 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(Set storage set, bytes32 value) private 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(Set storage set, bytes32 value) private 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;
                      if (lastIndex != toDeleteIndex) {
                          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] = valueIndex; // Replace lastValue's index to valueIndex
                      }
                      // 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(Set storage set, bytes32 value) private view returns (bool) {
                  return set._indexes[value] != 0;
              }
              /**
               * @dev Returns the number of values on the set. O(1).
               */
              function _length(Set storage set) private 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(Set storage set, uint256 index) private view returns (bytes32) {
                  return set._values[index];
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function _values(Set storage set) private view returns (bytes32[] memory) {
                  return set._values;
              }
              // Bytes32Set
              struct Bytes32Set {
                  Set _inner;
              }
              /**
               * @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) {
                  return _add(set._inner, value);
              }
              /**
               * @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) {
                  return _remove(set._inner, value);
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
                  return _contains(set._inner, value);
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(Bytes32Set storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @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) {
                  return _at(set._inner, index);
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  bytes32[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
              // AddressSet
              struct AddressSet {
                  Set _inner;
              }
              /**
               * @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(AddressSet storage set, address value) internal returns (bool) {
                  return _add(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @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) {
                  return _remove(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(AddressSet storage set, address value) internal view returns (bool) {
                  return _contains(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(AddressSet storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @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) {
                  return address(uint160(uint256(_at(set._inner, index))));
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(AddressSet storage set) internal view returns (address[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  address[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
              // UintSet
              struct UintSet {
                  Set _inner;
              }
              /**
               * @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(UintSet storage set, uint256 value) internal returns (bool) {
                  return _add(set._inner, bytes32(value));
              }
              /**
               * @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(UintSet storage set, uint256 value) internal returns (bool) {
                  return _remove(set._inner, bytes32(value));
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(UintSet storage set, uint256 value) internal view returns (bool) {
                  return _contains(set._inner, bytes32(value));
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(UintSet storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @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(UintSet storage set, uint256 index) internal view returns (uint256) {
                  return uint256(_at(set._inner, index));
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(UintSet storage set) internal view returns (uint256[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  uint256[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          import {EnumerableSet} from "openzeppelin-contracts/utils/structs/EnumerableSet.sol";
          interface IOperatorFilterRegistry {
              function isOperatorAllowed(address registrant, address operator) external returns (bool);
              function register(address registrant) external;
              function registerAndSubscribe(address registrant, address subscription) external;
              function registerAndCopyEntries(address registrant, address registrantToCopy) external;
              function updateOperator(address registrant, address operator, bool filtered) external;
              function updateOperators(address registrant, address[] calldata operators, bool filtered) external;
              function updateCodeHash(address registrant, bytes32 codehash, bool filtered) external;
              function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered) external;
              function subscribe(address registrant, address registrantToSubscribe) external;
              function unsubscribe(address registrant, bool copyExistingEntries) external;
              function subscriptionOf(address addr) external returns (address registrant);
              function subscribers(address registrant) external returns (address[] memory);
              function subscriberAt(address registrant, uint256 index) external returns (address);
              function copyEntriesOf(address registrant, address registrantToCopy) external;
              function isOperatorFiltered(address registrant, address operator) external returns (bool);
              function isCodeHashOfFiltered(address registrant, address operatorWithCode) external returns (bool);
              function isCodeHashFiltered(address registrant, bytes32 codeHash) external returns (bool);
              function filteredOperators(address addr) external returns (address[] memory);
              function filteredCodeHashes(address addr) external returns (bytes32[] memory);
              function filteredOperatorAt(address registrant, uint256 index) external returns (address);
              function filteredCodeHashAt(address registrant, uint256 index) external returns (bytes32);
              function isRegistered(address addr) external returns (bool);
              function codeHashOf(address addr) external returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          import {IOperatorFilterRegistry} from "./IOperatorFilterRegistry.sol";
          import {Ownable} from "openzeppelin-contracts/access/Ownable.sol";
          import {EnumerableSet} from "openzeppelin-contracts/utils/structs/EnumerableSet.sol";
          import {OperatorFilterRegistryErrorsAndEvents} from "./OperatorFilterRegistryErrorsAndEvents.sol";
          /**
           * @title  OperatorFilterRegistry
           * @notice Borrows heavily from the QQL BlacklistOperatorFilter contract:
           *         https://github.com/qql-art/contracts/blob/main/contracts/BlacklistOperatorFilter.sol
           * @notice This contracts allows tokens or token owners to register specific addresses or codeHashes that may be
           * *       restricted according to the isOperatorAllowed function.
           */
          contract OperatorFilterRegistry is IOperatorFilterRegistry, OperatorFilterRegistryErrorsAndEvents {
              using EnumerableSet for EnumerableSet.AddressSet;
              using EnumerableSet for EnumerableSet.Bytes32Set;
              /// @dev initialized accounts have a nonzero codehash (see https://eips.ethereum.org/EIPS/eip-1052)
              /// Note that this will also be a smart contract's codehash when making calls from its constructor.
              bytes32 constant EOA_CODEHASH = keccak256("");
              mapping(address => EnumerableSet.AddressSet) private _filteredOperators;
              mapping(address => EnumerableSet.Bytes32Set) private _filteredCodeHashes;
              mapping(address => address) private _registrations;
              mapping(address => EnumerableSet.AddressSet) private _subscribers;
              /**
               * @notice restricts method caller to the address or EIP-173 "owner()"
               */
              modifier onlyAddressOrOwner(address addr) {
                  if (msg.sender != addr) {
                      try Ownable(addr).owner() returns (address owner) {
                          if (msg.sender != owner) {
                              revert OnlyAddressOrOwner();
                          }
                      } catch (bytes memory reason) {
                          if (reason.length == 0) {
                              revert NotOwnable();
                          } else {
                              /// @solidity memory-safe-assembly
                              assembly {
                                  revert(add(32, reason), mload(reason))
                              }
                          }
                      }
                  }
                  _;
              }
              /**
               * @notice Returns true if operator is not filtered for a given token, either by address or codeHash. Also returns
               *         true if supplied registrant address is not registered.
               */
              function isOperatorAllowed(address registrant, address operator) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      EnumerableSet.AddressSet storage filteredOperatorsRef;
                      EnumerableSet.Bytes32Set storage filteredCodeHashesRef;
                      filteredOperatorsRef = _filteredOperators[registration];
                      filteredCodeHashesRef = _filteredCodeHashes[registration];
                      if (filteredOperatorsRef.contains(operator)) {
                          revert AddressFiltered(operator);
                      }
                      if (operator.code.length > 0) {
                          bytes32 codeHash = operator.codehash;
                          if (filteredCodeHashesRef.contains(codeHash)) {
                              revert CodeHashFiltered(operator, codeHash);
                          }
                      }
                  }
                  return true;
              }
              //////////////////
              // AUTH METHODS //
              //////////////////
              /**
               * @notice Registers an address with the registry. May be called by address itself or by EIP-173 owner.
               */
              function register(address registrant) external onlyAddressOrOwner(registrant) {
                  if (_registrations[registrant] != address(0)) {
                      revert AlreadyRegistered();
                  }
                  _registrations[registrant] = registrant;
                  emit RegistrationUpdated(registrant, true);
              }
              /**
               * @notice Unregisters an address with the registry and removes its subscription. May be called by address itself or by EIP-173 owner.
               *         Note that this does not remove any filtered addresses or codeHashes.
               *         Also note that any subscriptions to this registrant will still be active and follow the existing filtered addresses and codehashes.
               */
              function unregister(address registrant) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      _subscribers[registration].remove(registrant);
                      emit SubscriptionUpdated(registrant, registration, false);
                  }
                  _registrations[registrant] = address(0);
                  emit RegistrationUpdated(registrant, false);
              }
              /**
               * @notice Registers an address with the registry and "subscribes" to another address's filtered operators and codeHashes.
               */
              function registerAndSubscribe(address registrant, address subscription) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      revert AlreadyRegistered();
                  }
                  if (registrant == subscription) {
                      revert CannotSubscribeToSelf();
                  }
                  address subscriptionRegistration = _registrations[subscription];
                  if (subscriptionRegistration == address(0)) {
                      revert NotRegistered(subscription);
                  }
                  if (subscriptionRegistration != subscription) {
                      revert CannotSubscribeToRegistrantWithSubscription(subscription);
                  }
                  _registrations[registrant] = subscription;
                  _subscribers[subscription].add(registrant);
                  emit RegistrationUpdated(registrant, true);
                  emit SubscriptionUpdated(registrant, subscription, true);
              }
              /**
               * @notice Registers an address with the registry and copies the filtered operators and codeHashes from another
               *         address without subscribing.
               */
              function registerAndCopyEntries(address registrant, address registrantToCopy)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  if (registrantToCopy == registrant) {
                      revert CannotCopyFromSelf();
                  }
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      revert AlreadyRegistered();
                  }
                  address registrantRegistration = _registrations[registrantToCopy];
                  if (registrantRegistration == address(0)) {
                      revert NotRegistered(registrantToCopy);
                  }
                  _registrations[registrant] = registrant;
                  emit RegistrationUpdated(registrant, true);
                  _copyEntries(registrant, registrantToCopy);
              }
              /**
               * @notice Update an operator address for a registered address - when filtered is true, the operator is filtered.
               */
              function updateOperator(address registrant, address operator, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrant];
                  if (!filtered) {
                      bool removed = filteredOperatorsRef.remove(operator);
                      if (!removed) {
                          revert AddressNotFiltered(operator);
                      }
                  } else {
                      bool added = filteredOperatorsRef.add(operator);
                      if (!added) {
                          revert AddressAlreadyFiltered(operator);
                      }
                  }
                  emit OperatorUpdated(registrant, operator, filtered);
              }
              /**
               * @notice Update a codeHash for a registered address - when filtered is true, the codeHash is filtered.
               */
              function updateCodeHash(address registrant, bytes32 codeHash, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  if (codeHash == EOA_CODEHASH) {
                      revert CannotFilterEOAs();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrant];
                  if (!filtered) {
                      bool removed = filteredCodeHashesRef.remove(codeHash);
                      if (!removed) {
                          revert CodeHashNotFiltered(codeHash);
                      }
                  } else {
                      bool added = filteredCodeHashesRef.add(codeHash);
                      if (!added) {
                          revert CodeHashAlreadyFiltered(codeHash);
                      }
                  }
                  emit CodeHashUpdated(registrant, codeHash, filtered);
              }
              /**
               * @notice Update multiple operators for a registered address - when filtered is true, the operators will be filtered. Reverts on duplicates.
               */
              function updateOperators(address registrant, address[] calldata operators, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrant];
                  uint256 operatorsLength = operators.length;
                  unchecked {
                      if (!filtered) {
                          for (uint256 i = 0; i < operatorsLength; ++i) {
                              address operator = operators[i];
                              bool removed = filteredOperatorsRef.remove(operator);
                              if (!removed) {
                                  revert AddressNotFiltered(operator);
                              }
                          }
                      } else {
                          for (uint256 i = 0; i < operatorsLength; ++i) {
                              address operator = operators[i];
                              bool added = filteredOperatorsRef.add(operator);
                              if (!added) {
                                  revert AddressAlreadyFiltered(operator);
                              }
                          }
                      }
                  }
                  emit OperatorsUpdated(registrant, operators, filtered);
              }
              /**
               * @notice Update multiple codeHashes for a registered address - when filtered is true, the codeHashes will be filtered. Reverts on duplicates.
               */
              function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrant];
                  uint256 codeHashesLength = codeHashes.length;
                  unchecked {
                      if (!filtered) {
                          for (uint256 i = 0; i < codeHashesLength; ++i) {
                              bytes32 codeHash = codeHashes[i];
                              bool removed = filteredCodeHashesRef.remove(codeHash);
                              if (!removed) {
                                  revert CodeHashNotFiltered(codeHash);
                              }
                          }
                      } else {
                          for (uint256 i = 0; i < codeHashesLength; ++i) {
                              bytes32 codeHash = codeHashes[i];
                              if (codeHash == EOA_CODEHASH) {
                                  revert CannotFilterEOAs();
                              }
                              bool added = filteredCodeHashesRef.add(codeHash);
                              if (!added) {
                                  revert CodeHashAlreadyFiltered(codeHash);
                              }
                          }
                      }
                  }
                  emit CodeHashesUpdated(registrant, codeHashes, filtered);
              }
              /**
               * @notice Subscribe an address to another registrant's filtered operators and codeHashes. Will remove previous
               *         subscription if present.
               *         Note that accounts with subscriptions may go on to subscribe to other accounts - in this case,
               *         subscriptions will not be forwarded. Instead the former subscription's existing entries will still be
               *         used.
               */
              function subscribe(address registrant, address newSubscription) external onlyAddressOrOwner(registrant) {
                  if (registrant == newSubscription) {
                      revert CannotSubscribeToSelf();
                  }
                  if (newSubscription == address(0)) {
                      revert CannotSubscribeToZeroAddress();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration == newSubscription) {
                      revert AlreadySubscribed(newSubscription);
                  }
                  address newSubscriptionRegistration = _registrations[newSubscription];
                  if (newSubscriptionRegistration == address(0)) {
                      revert NotRegistered(newSubscription);
                  }
                  if (newSubscriptionRegistration != newSubscription) {
                      revert CannotSubscribeToRegistrantWithSubscription(newSubscription);
                  }
                  if (registration != registrant) {
                      _subscribers[registration].remove(registrant);
                      emit SubscriptionUpdated(registrant, registration, false);
                  }
                  _registrations[registrant] = newSubscription;
                  _subscribers[newSubscription].add(registrant);
                  emit SubscriptionUpdated(registrant, newSubscription, true);
              }
              /**
               * @notice Unsubscribe an address from its current subscribed registrant, and optionally copy its filtered operators and codeHashes.
               */
              function unsubscribe(address registrant, bool copyExistingEntries) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration == registrant) {
                      revert NotSubscribed();
                  }
                  _subscribers[registration].remove(registrant);
                  _registrations[registrant] = registrant;
                  emit SubscriptionUpdated(registrant, registration, false);
                  if (copyExistingEntries) {
                      _copyEntries(registrant, registration);
                  }
              }
              /**
               * @notice Copy filtered operators and codeHashes from a different registrantToCopy to addr.
               */
              function copyEntriesOf(address registrant, address registrantToCopy) external onlyAddressOrOwner(registrant) {
                  if (registrant == registrantToCopy) {
                      revert CannotCopyFromSelf();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  address registrantRegistration = _registrations[registrantToCopy];
                  if (registrantRegistration == address(0)) {
                      revert NotRegistered(registrantToCopy);
                  }
                  _copyEntries(registrant, registrantToCopy);
              }
              /// @dev helper to copy entries from registrantToCopy to registrant and emit events
              function _copyEntries(address registrant, address registrantToCopy) private {
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrantToCopy];
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrantToCopy];
                  uint256 filteredOperatorsLength = filteredOperatorsRef.length();
                  uint256 filteredCodeHashesLength = filteredCodeHashesRef.length();
                  unchecked {
                      for (uint256 i = 0; i < filteredOperatorsLength; ++i) {
                          address operator = filteredOperatorsRef.at(i);
                          bool added = _filteredOperators[registrant].add(operator);
                          if (added) {
                              emit OperatorUpdated(registrant, operator, true);
                          }
                      }
                      for (uint256 i = 0; i < filteredCodeHashesLength; ++i) {
                          bytes32 codehash = filteredCodeHashesRef.at(i);
                          bool added = _filteredCodeHashes[registrant].add(codehash);
                          if (added) {
                              emit CodeHashUpdated(registrant, codehash, true);
                          }
                      }
                  }
              }
              //////////////////
              // VIEW METHODS //
              //////////////////
              /**
               * @notice Get the subscription address of a given registrant, if any.
               */
              function subscriptionOf(address registrant) external view returns (address subscription) {
                  subscription = _registrations[registrant];
                  if (subscription == address(0)) {
                      revert NotRegistered(registrant);
                  } else if (subscription == registrant) {
                      subscription = address(0);
                  }
              }
              /**
               * @notice Get the set of addresses subscribed to a given registrant.
               *         Note that order is not guaranteed as updates are made.
               */
              function subscribers(address registrant) external view returns (address[] memory) {
                  return _subscribers[registrant].values();
              }
              /**
               * @notice Get the subscriber at a given index in the set of addresses subscribed to a given registrant.
               *         Note that order is not guaranteed as updates are made.
               */
              function subscriberAt(address registrant, uint256 index) external view returns (address) {
                  return _subscribers[registrant].at(index);
              }
              /**
               * @notice Returns true if operator is filtered by a given address or its subscription.
               */
              function isOperatorFiltered(address registrant, address operator) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].contains(operator);
                  }
                  return _filteredOperators[registrant].contains(operator);
              }
              /**
               * @notice Returns true if a codeHash is filtered by a given address or its subscription.
               */
              function isCodeHashFiltered(address registrant, bytes32 codeHash) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].contains(codeHash);
                  }
                  return _filteredCodeHashes[registrant].contains(codeHash);
              }
              /**
               * @notice Returns true if the hash of an address's code is filtered by a given address or its subscription.
               */
              function isCodeHashOfFiltered(address registrant, address operatorWithCode) external view returns (bool) {
                  bytes32 codeHash = operatorWithCode.codehash;
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].contains(codeHash);
                  }
                  return _filteredCodeHashes[registrant].contains(codeHash);
              }
              /**
               * @notice Returns true if an address has registered
               */
              function isRegistered(address registrant) external view returns (bool) {
                  return _registrations[registrant] != address(0);
              }
              /**
               * @notice Returns a list of filtered operators for a given address or its subscription.
               */
              function filteredOperators(address registrant) external view returns (address[] memory) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].values();
                  }
                  return _filteredOperators[registrant].values();
              }
              /**
               * @notice Returns the set of filtered codeHashes for a given address or its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredCodeHashes(address registrant) external view returns (bytes32[] memory) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].values();
                  }
                  return _filteredCodeHashes[registrant].values();
              }
              /**
               * @notice Returns the filtered operator at the given index of the set of filtered operators for a given address or
               *         its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredOperatorAt(address registrant, uint256 index) external view returns (address) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].at(index);
                  }
                  return _filteredOperators[registrant].at(index);
              }
              /**
               * @notice Returns the filtered codeHash at the given index of the list of filtered codeHashes for a given address or
               *         its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredCodeHashAt(address registrant, uint256 index) external view returns (bytes32) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].at(index);
                  }
                  return _filteredCodeHashes[registrant].at(index);
              }
              /// @dev Convenience method to compute the code hash of an arbitrary contract
              function codeHashOf(address a) external view returns (bytes32) {
                  return a.codehash;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          contract OperatorFilterRegistryErrorsAndEvents {
              error CannotFilterEOAs();
              error AddressAlreadyFiltered(address operator);
              error AddressNotFiltered(address operator);
              error CodeHashAlreadyFiltered(bytes32 codeHash);
              error CodeHashNotFiltered(bytes32 codeHash);
              error OnlyAddressOrOwner();
              error NotRegistered(address registrant);
              error AlreadyRegistered();
              error AlreadySubscribed(address subscription);
              error NotSubscribed();
              error CannotUpdateWhileSubscribed(address subscription);
              error CannotSubscribeToSelf();
              error CannotSubscribeToZeroAddress();
              error NotOwnable();
              error AddressFiltered(address filtered);
              error CodeHashFiltered(address account, bytes32 codeHash);
              error CannotSubscribeToRegistrantWithSubscription(address registrant);
              error CannotCopyFromSelf();
              event RegistrationUpdated(address indexed registrant, bool indexed registered);
              event OperatorUpdated(address indexed registrant, address indexed operator, bool indexed filtered);
              event OperatorsUpdated(address indexed registrant, address[] operators, bool indexed filtered);
              event CodeHashUpdated(address indexed registrant, bytes32 indexed codeHash, bool indexed filtered);
              event CodeHashesUpdated(address indexed registrant, bytes32[] codeHashes, bool indexed filtered);
              event SubscriptionUpdated(address indexed registrant, address indexed subscription, bool indexed subscribed);
          }