// File: @ensdomains/ens/contracts/ENS.sol

pragma solidity >=0.4.24;

interface ENS {

    // Logged when the owner of a node assigns a new owner to a subnode.
    event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);

    // Logged when the owner of a node transfers ownership to a new account.
    event Transfer(bytes32 indexed node, address owner);

    // Logged when the resolver for a node changes.
    event NewResolver(bytes32 indexed node, address resolver);

    // Logged when the TTL of a node changes
    event NewTTL(bytes32 indexed node, uint64 ttl);

    // Logged when an operator is added or removed.
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function setRecord(bytes32 node, address owner, address resolver, uint64 ttl) external;
    function setSubnodeRecord(bytes32 node, bytes32 label, address owner, address resolver, uint64 ttl) external;
    function setSubnodeOwner(bytes32 node, bytes32 label, address owner) external returns(bytes32);
    function setResolver(bytes32 node, address resolver) external;
    function setOwner(bytes32 node, address owner) external;
    function setTTL(bytes32 node, uint64 ttl) external;
    function setApprovalForAll(address operator, bool approved) external;
    function owner(bytes32 node) external view returns (address);
    function resolver(bytes32 node) external view returns (address);
    function ttl(bytes32 node) external view returns (uint64);
    function recordExists(bytes32 node) external view returns (bool);
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// File: openzeppelin-solidity/contracts/introspection/IERC165.sol

pragma solidity ^0.5.0;

/**
 * @title IERC165
 * @dev https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
 */
interface IERC165 {
    /**
     * @notice Query if a contract implements an interface
     * @param interfaceId The interface identifier, as specified in ERC-165
     * @dev Interface identification is specified in ERC-165. This function
     * uses less than 30,000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721.sol

pragma solidity ^0.5.0;


/**
 * @title ERC721 Non-Fungible Token Standard basic interface
 * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
 */
contract IERC721 is IERC165 {
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function balanceOf(address owner) public view returns (uint256 balance);
    function ownerOf(uint256 tokenId) public view returns (address owner);

    function approve(address to, uint256 tokenId) public;
    function getApproved(uint256 tokenId) public view returns (address operator);

    function setApprovalForAll(address operator, bool _approved) public;
    function isApprovedForAll(address owner, address operator) public view returns (bool);

    function transferFrom(address from, address to, uint256 tokenId) public;
    function safeTransferFrom(address from, address to, uint256 tokenId) public;

    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public;
}

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721Receiver.sol

pragma solidity ^0.5.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
contract IERC721Receiver {
    /**
     * @notice Handle the receipt of an NFT
     * @dev The ERC721 smart contract calls this function on the recipient
     * after a `safeTransfer`. This function MUST return the function selector,
     * otherwise the caller will revert the transaction. The selector to be
     * returned can be obtained as `this.onERC721Received.selector`. This
     * function MAY throw to revert and reject the transfer.
     * Note: the ERC721 contract address is always the message sender.
     * @param operator The address which called `safeTransferFrom` function
     * @param from The address which previously owned the token
     * @param tokenId The NFT identifier which is being transferred
     * @param data Additional data with no specified format
     * @return `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
     */
    function onERC721Received(address operator, address from, uint256 tokenId, bytes memory data)
    public returns (bytes4);
}

// File: openzeppelin-solidity/contracts/math/SafeMath.sol

pragma solidity ^0.5.0;

/**
 * @title SafeMath
 * @dev Unsigned math operations with safety checks that revert on error
 */
library SafeMath {
    /**
    * @dev Multiplies two unsigned integers, reverts on overflow.
    */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b);

        return c;
    }

    /**
    * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
    */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
    * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
    */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;

        return c;
    }

    /**
    * @dev Adds two unsigned integers, reverts on overflow.
    */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);

        return c;
    }

    /**
    * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
    * reverts when dividing by zero.
    */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }
}

// File: openzeppelin-solidity/contracts/utils/Address.sol

pragma solidity ^0.5.0;

/**
 * Utility library of inline functions on addresses
 */
library Address {
    /**
     * Returns whether the target address is a contract
     * @dev This function will return false if invoked during the constructor of a contract,
     * as the code is not actually created until after the constructor finishes.
     * @param account address of the account to check
     * @return whether the target address is a contract
     */
    function isContract(address account) internal view returns (bool) {
        uint256 size;
        // XXX Currently there is no better way to check if there is a contract in an address
        // than to check the size of the code at that address.
        // See https://ethereum.stackexchange.com/a/14016/36603
        // for more details about how this works.
        // TODO Check this again before the Serenity release, because all addresses will be
        // contracts then.
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
}

// File: openzeppelin-solidity/contracts/introspection/ERC165.sol

pragma solidity ^0.5.0;


/**
 * @title ERC165
 * @author Matt Condon (@shrugs)
 * @dev Implements ERC165 using a lookup table.
 */
contract ERC165 is IERC165 {
    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
    /**
     * 0x01ffc9a7 ===
     *     bytes4(keccak256('supportsInterface(bytes4)'))
     */

    /**
     * @dev a mapping of interface id to whether or not it's supported
     */
    mapping(bytes4 => bool) private _supportedInterfaces;

    /**
     * @dev A contract implementing SupportsInterfaceWithLookup
     * implement ERC165 itself
     */
    constructor () internal {
        _registerInterface(_INTERFACE_ID_ERC165);
    }

    /**
     * @dev implement supportsInterface(bytes4) using a lookup table
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool) {
        return _supportedInterfaces[interfaceId];
    }

    /**
     * @dev internal method for registering an interface
     */
    function _registerInterface(bytes4 interfaceId) internal {
        require(interfaceId != 0xffffffff);
        _supportedInterfaces[interfaceId] = true;
    }
}

// File: openzeppelin-solidity/contracts/token/ERC721/ERC721.sol

pragma solidity ^0.5.0;






/**
 * @title ERC721 Non-Fungible Token Standard basic implementation
 * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
 */
contract ERC721 is ERC165, IERC721 {
    using SafeMath for uint256;
    using Address for address;

    // Equals to `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
    // which can be also obtained as `IERC721Receiver(0).onERC721Received.selector`
    bytes4 private constant _ERC721_RECEIVED = 0x150b7a02;

    // Mapping from token ID to owner
    mapping (uint256 => address) private _tokenOwner;

    // Mapping from token ID to approved address
    mapping (uint256 => address) private _tokenApprovals;

    // Mapping from owner to number of owned token
    mapping (address => uint256) private _ownedTokensCount;

    // Mapping from owner to operator approvals
    mapping (address => mapping (address => bool)) private _operatorApprovals;

    bytes4 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;
    /*
     * 0x80ac58cd ===
     *     bytes4(keccak256('balanceOf(address)')) ^
     *     bytes4(keccak256('ownerOf(uint256)')) ^
     *     bytes4(keccak256('approve(address,uint256)')) ^
     *     bytes4(keccak256('getApproved(uint256)')) ^
     *     bytes4(keccak256('setApprovalForAll(address,bool)')) ^
     *     bytes4(keccak256('isApprovedForAll(address,address)')) ^
     *     bytes4(keccak256('transferFrom(address,address,uint256)')) ^
     *     bytes4(keccak256('safeTransferFrom(address,address,uint256)')) ^
     *     bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)'))
     */

    constructor () public {
        // register the supported interfaces to conform to ERC721 via ERC165
        _registerInterface(_INTERFACE_ID_ERC721);
    }

    /**
     * @dev Gets the balance of the specified address
     * @param owner address to query the balance of
     * @return uint256 representing the amount owned by the passed address
     */
    function balanceOf(address owner) public view returns (uint256) {
        require(owner != address(0));
        return _ownedTokensCount[owner];
    }

    /**
     * @dev Gets the owner of the specified token ID
     * @param tokenId uint256 ID of the token to query the owner of
     * @return owner address currently marked as the owner of the given token ID
     */
    function ownerOf(uint256 tokenId) public view returns (address) {
        address owner = _tokenOwner[tokenId];
        require(owner != address(0));
        return owner;
    }

    /**
     * @dev Approves another address to transfer the given token ID
     * The zero address indicates there is no approved address.
     * There can only be one approved address per token at a given time.
     * Can only be called by the token owner or an approved operator.
     * @param to address to be approved for the given token ID
     * @param tokenId uint256 ID of the token to be approved
     */
    function approve(address to, uint256 tokenId) public {
        address owner = ownerOf(tokenId);
        require(to != owner);
        require(msg.sender == owner || isApprovedForAll(owner, msg.sender));

        _tokenApprovals[tokenId] = to;
        emit Approval(owner, to, tokenId);
    }

    /**
     * @dev Gets the approved address for a token ID, or zero if no address set
     * Reverts if the token ID does not exist.
     * @param tokenId uint256 ID of the token to query the approval of
     * @return address currently approved for the given token ID
     */
    function getApproved(uint256 tokenId) public view returns (address) {
        require(_exists(tokenId));
        return _tokenApprovals[tokenId];
    }

    /**
     * @dev Sets or unsets the approval of a given operator
     * An operator is allowed to transfer all tokens of the sender on their behalf
     * @param to operator address to set the approval
     * @param approved representing the status of the approval to be set
     */
    function setApprovalForAll(address to, bool approved) public {
        require(to != msg.sender);
        _operatorApprovals[msg.sender][to] = approved;
        emit ApprovalForAll(msg.sender, to, approved);
    }

    /**
     * @dev Tells whether an operator is approved by a given owner
     * @param owner owner address which you want to query the approval of
     * @param operator operator address which you want to query the approval of
     * @return bool whether the given operator is approved by the given owner
     */
    function isApprovedForAll(address owner, address operator) public view returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev Transfers the ownership of a given token ID to another address
     * Usage of this method is discouraged, use `safeTransferFrom` whenever possible
     * Requires the msg sender to be the owner, approved, or operator
     * @param from current owner of the token
     * @param to address to receive the ownership of the given token ID
     * @param tokenId uint256 ID of the token to be transferred
    */
    function transferFrom(address from, address to, uint256 tokenId) public {
        require(_isApprovedOrOwner(msg.sender, tokenId));

        _transferFrom(from, to, tokenId);
    }

    /**
     * @dev Safely transfers the ownership of a given token ID to another address
     * If the target address is a contract, it must implement `onERC721Received`,
     * which is called upon a safe transfer, and return the magic value
     * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
     * the transfer is reverted.
     *
     * Requires the msg sender to be the owner, approved, or operator
     * @param from current owner of the token
     * @param to address to receive the ownership of the given token ID
     * @param tokenId uint256 ID of the token to be transferred
    */
    function safeTransferFrom(address from, address to, uint256 tokenId) public {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev Safely transfers the ownership of a given token ID to another address
     * If the target address is a contract, it must implement `onERC721Received`,
     * which is called upon a safe transfer, and return the magic value
     * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
     * the transfer is reverted.
     * Requires the msg sender to be the owner, approved, or operator
     * @param from current owner of the token
     * @param to address to receive the ownership of the given token ID
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes data to send along with a safe transfer check
     */
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public {
        transferFrom(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, _data));
    }

    /**
     * @dev Returns whether the specified token exists
     * @param tokenId uint256 ID of the token to query the existence of
     * @return whether the token exists
     */
    function _exists(uint256 tokenId) internal view returns (bool) {
        address owner = _tokenOwner[tokenId];
        return owner != address(0);
    }

    /**
     * @dev Returns whether the given spender can transfer a given token ID
     * @param spender address of the spender to query
     * @param tokenId uint256 ID of the token to be transferred
     * @return bool whether the msg.sender is approved for the given token ID,
     *    is an operator of the owner, or is the owner of the token
     */
    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view returns (bool) {
        address owner = ownerOf(tokenId);
        return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
    }

    /**
     * @dev Internal function to mint a new token
     * Reverts if the given token ID already exists
     * @param to The address that will own the minted token
     * @param tokenId uint256 ID of the token to be minted
     */
    function _mint(address to, uint256 tokenId) internal {
        require(to != address(0));
        require(!_exists(tokenId));

        _tokenOwner[tokenId] = to;
        _ownedTokensCount[to] = _ownedTokensCount[to].add(1);

        emit Transfer(address(0), to, tokenId);
    }

    /**
     * @dev Internal function to burn a specific token
     * Reverts if the token does not exist
     * Deprecated, use _burn(uint256) instead.
     * @param owner owner of the token to burn
     * @param tokenId uint256 ID of the token being burned
     */
    function _burn(address owner, uint256 tokenId) internal {
        require(ownerOf(tokenId) == owner);

        _clearApproval(tokenId);

        _ownedTokensCount[owner] = _ownedTokensCount[owner].sub(1);
        _tokenOwner[tokenId] = address(0);

        emit Transfer(owner, address(0), tokenId);
    }

    /**
     * @dev Internal function to burn a specific token
     * Reverts if the token does not exist
     * @param tokenId uint256 ID of the token being burned
     */
    function _burn(uint256 tokenId) internal {
        _burn(ownerOf(tokenId), tokenId);
    }

    /**
     * @dev Internal function to transfer ownership of a given token ID to another address.
     * As opposed to transferFrom, this imposes no restrictions on msg.sender.
     * @param from current owner of the token
     * @param to address to receive the ownership of the given token ID
     * @param tokenId uint256 ID of the token to be transferred
    */
    function _transferFrom(address from, address to, uint256 tokenId) internal {
        require(ownerOf(tokenId) == from);
        require(to != address(0));

        _clearApproval(tokenId);

        _ownedTokensCount[from] = _ownedTokensCount[from].sub(1);
        _ownedTokensCount[to] = _ownedTokensCount[to].add(1);

        _tokenOwner[tokenId] = to;

        emit Transfer(from, to, tokenId);
    }

    /**
     * @dev Internal function to invoke `onERC721Received` on a target address
     * The call is not executed if the target address is not a contract
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes optional data to send along with the call
     * @return whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)
        internal returns (bool)
    {
        if (!to.isContract()) {
            return true;
        }

        bytes4 retval = IERC721Receiver(to).onERC721Received(msg.sender, from, tokenId, _data);
        return (retval == _ERC721_RECEIVED);
    }

    /**
     * @dev Private function to clear current approval of a given token ID
     * @param tokenId uint256 ID of the token to be transferred
     */
    function _clearApproval(uint256 tokenId) private {
        if (_tokenApprovals[tokenId] != address(0)) {
            _tokenApprovals[tokenId] = address(0);
        }
    }
}

// File: openzeppelin-solidity/contracts/ownership/Ownable.sol

pragma solidity ^0.5.0;

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    constructor () internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
    }

    /**
     * @return the address of the owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(isOwner());
        _;
    }

    /**
     * @return true if `msg.sender` is the owner of the contract.
     */
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     * @notice Renouncing to ownership will leave the contract without an owner.
     * It will not be possible to call the functions with the `onlyOwner`
     * modifier anymore.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0));
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: @ensdomains/ethregistrar/contracts/BaseRegistrar.sol

pragma solidity >=0.4.24;




contract BaseRegistrar is IERC721, Ownable {
    uint constant public GRACE_PERIOD = 90 days;

    event ControllerAdded(address indexed controller);
    event ControllerRemoved(address indexed controller);
    event NameMigrated(uint256 indexed id, address indexed owner, uint expires);
    event NameRegistered(uint256 indexed id, address indexed owner, uint expires);
    event NameRenewed(uint256 indexed id, uint expires);

    // The ENS registry
    ENS public ens;

    // The namehash of the TLD this registrar owns (eg, .eth)
    bytes32 public baseNode;

    // A map of addresses that are authorised to register and renew names.
    mapping(address=>bool) public controllers;

    // Authorises a controller, who can register and renew domains.
    function addController(address controller) external;

    // Revoke controller permission for an address.
    function removeController(address controller) external;

    // Set the resolver for the TLD this registrar manages.
    function setResolver(address resolver) external;

    // Returns the expiration timestamp of the specified label hash.
    function nameExpires(uint256 id) external view returns(uint);

    // Returns true iff the specified name is available for registration.
    function available(uint256 id) public view returns(bool);

    /**
     * @dev Register a name.
     */
    function register(uint256 id, address owner, uint duration) external returns(uint);

    function renew(uint256 id, uint duration) external returns(uint);

    /**
     * @dev Reclaim ownership of a name in ENS, if you own it in the registrar.
     */
    function reclaim(uint256 id, address owner) external;
}

// File: @ensdomains/ethregistrar/contracts/BaseRegistrarImplementation.sol

pragma solidity ^0.5.0;




contract BaseRegistrarImplementation is BaseRegistrar, ERC721 {
    // A map of expiry times
    mapping(uint256=>uint) expiries;

    bytes4 constant private INTERFACE_META_ID = bytes4(keccak256("supportsInterface(bytes4)"));
    bytes4 constant private ERC721_ID = bytes4(
        keccak256("balanceOf(address)") ^
        keccak256("ownerOf(uint256)") ^
        keccak256("approve(address,uint256)") ^
        keccak256("getApproved(uint256)") ^
        keccak256("setApprovalForAll(address,bool)") ^
        keccak256("isApprovedForAll(address,address)") ^
        keccak256("transferFrom(address,address,uint256)") ^
        keccak256("safeTransferFrom(address,address,uint256)") ^
        keccak256("safeTransferFrom(address,address,uint256,bytes)")
    );
    bytes4 constant private RECLAIM_ID = bytes4(keccak256("reclaim(uint256,address)"));

    constructor(ENS _ens, bytes32 _baseNode) public {
        ens = _ens;
        baseNode = _baseNode;
    }

    modifier live {
        require(ens.owner(baseNode) == address(this));
        _;
    }

    modifier onlyController {
        require(controllers[msg.sender]);
        _;
    }

    /**
     * @dev Gets the owner of the specified token ID. Names become unowned
     *      when their registration expires.
     * @param tokenId uint256 ID of the token to query the owner of
     * @return address currently marked as the owner of the given token ID
     */
    function ownerOf(uint256 tokenId) public view returns (address) {
        require(expiries[tokenId] > now);
        return super.ownerOf(tokenId);
    }

    // Authorises a controller, who can register and renew domains.
    function addController(address controller) external onlyOwner {
        controllers[controller] = true;
        emit ControllerAdded(controller);
    }

    // Revoke controller permission for an address.
    function removeController(address controller) external onlyOwner {
        controllers[controller] = false;
        emit ControllerRemoved(controller);
    }

    // Set the resolver for the TLD this registrar manages.
    function setResolver(address resolver) external onlyOwner {
        ens.setResolver(baseNode, resolver);
    }

    // Returns the expiration timestamp of the specified id.
    function nameExpires(uint256 id) external view returns(uint) {
        return expiries[id];
    }

    // Returns true iff the specified name is available for registration.
    function available(uint256 id) public view returns(bool) {
        // Not available if it's registered here or in its grace period.
        return expiries[id] + GRACE_PERIOD < now;
    }

    /**
     * @dev Register a name.
     * @param id The token ID (keccak256 of the label).
     * @param owner The address that should own the registration.
     * @param duration Duration in seconds for the registration.
     */
    function register(uint256 id, address owner, uint duration) external returns(uint) {
      return _register(id, owner, duration, true);
    }

    /**
     * @dev Register a name, without modifying the registry.
     * @param id The token ID (keccak256 of the label).
     * @param owner The address that should own the registration.
     * @param duration Duration in seconds for the registration.
     */
    function registerOnly(uint256 id, address owner, uint duration) external returns(uint) {
      return _register(id, owner, duration, false);
    }

    function _register(uint256 id, address owner, uint duration, bool updateRegistry) internal live onlyController returns(uint) {
        require(available(id));
        require(now + duration + GRACE_PERIOD > now + GRACE_PERIOD); // Prevent future overflow

        expiries[id] = now + duration;
        if(_exists(id)) {
            // Name was previously owned, and expired
            _burn(id);
        }
        _mint(owner, id);
        if(updateRegistry) {
            ens.setSubnodeOwner(baseNode, bytes32(id), owner);
        }

        emit NameRegistered(id, owner, now + duration);

        return now + duration;
    }

    function renew(uint256 id, uint duration) external live onlyController returns(uint) {
        require(expiries[id] + GRACE_PERIOD >= now); // Name must be registered here or in grace period
        require(expiries[id] + duration + GRACE_PERIOD > duration + GRACE_PERIOD); // Prevent future overflow

        expiries[id] += duration;
        emit NameRenewed(id, expiries[id]);
        return expiries[id];
    }

    /**
     * @dev Reclaim ownership of a name in ENS, if you own it in the registrar.
     */
    function reclaim(uint256 id, address owner) external live {
        require(_isApprovedOrOwner(msg.sender, id));
        ens.setSubnodeOwner(baseNode, bytes32(id), owner);
    }

    function supportsInterface(bytes4 interfaceID) external view returns (bool) {
        return interfaceID == INTERFACE_META_ID ||
               interfaceID == ERC721_ID ||
               interfaceID == RECLAIM_ID;
    }
}

// File: @ensdomains/ens/contracts/ENS.sol

pragma solidity >=0.4.24;

interface ENS {

    // Logged when the owner of a node assigns a new owner to a subnode.
    event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);

    // Logged when the owner of a node transfers ownership to a new account.
    event Transfer(bytes32 indexed node, address owner);

    // Logged when the resolver for a node changes.
    event NewResolver(bytes32 indexed node, address resolver);

    // Logged when the TTL of a node changes
    event NewTTL(bytes32 indexed node, uint64 ttl);

    // Logged when an operator is added or removed.
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function setRecord(bytes32 node, address owner, address resolver, uint64 ttl) external;
    function setSubnodeRecord(bytes32 node, bytes32 label, address owner, address resolver, uint64 ttl) external;
    function setSubnodeOwner(bytes32 node, bytes32 label, address owner) external returns(bytes32);
    function setResolver(bytes32 node, address resolver) external;
    function setOwner(bytes32 node, address owner) external;
    function setTTL(bytes32 node, uint64 ttl) external;
    function setApprovalForAll(address operator, bool approved) external;
    function owner(bytes32 node) external view returns (address);
    function resolver(bytes32 node) external view returns (address);
    function ttl(bytes32 node) external view returns (uint64);
    function recordExists(bytes32 node) external view returns (bool);
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// File: @ensdomains/ens/contracts/ENSRegistry.sol

pragma solidity ^0.5.0;


/**
 * The ENS registry contract.
 */
contract ENSRegistry is ENS {

    struct Record {
        address owner;
        address resolver;
        uint64 ttl;
    }

    mapping (bytes32 => Record) records;
    mapping (address => mapping(address => bool)) operators;

    // Permits modifications only by the owner of the specified node.
    modifier authorised(bytes32 node) {
        address owner = records[node].owner;
        require(owner == msg.sender || operators[owner][msg.sender]);
        _;
    }

    /**
     * @dev Constructs a new ENS registrar.
     */
    constructor() public {
        records[0x0].owner = msg.sender;
    }

    /**
     * @dev Sets the record for a node.
     * @param node The node to update.
     * @param owner The address of the new owner.
     * @param resolver The address of the resolver.
     * @param ttl The TTL in seconds.
     */
    function setRecord(bytes32 node, address owner, address resolver, uint64 ttl) external {
        setOwner(node, owner);
        _setResolverAndTTL(node, resolver, ttl);
    }

    /**
     * @dev Sets the record for a subnode.
     * @param node The parent node.
     * @param label The hash of the label specifying the subnode.
     * @param owner The address of the new owner.
     * @param resolver The address of the resolver.
     * @param ttl The TTL in seconds.
     */
    function setSubnodeRecord(bytes32 node, bytes32 label, address owner, address resolver, uint64 ttl) external {
        bytes32 subnode = setSubnodeOwner(node, label, owner);
        _setResolverAndTTL(subnode, resolver, ttl);
    }

    /**
     * @dev Transfers ownership of a node to a new address. May only be called by the current owner of the node.
     * @param node The node to transfer ownership of.
     * @param owner The address of the new owner.
     */
    function setOwner(bytes32 node, address owner) public authorised(node) {
        _setOwner(node, owner);
        emit Transfer(node, owner);
    }

    /**
     * @dev Transfers ownership of a subnode keccak256(node, label) to a new address. May only be called by the owner of the parent node.
     * @param node The parent node.
     * @param label The hash of the label specifying the subnode.
     * @param owner The address of the new owner.
     */
    function setSubnodeOwner(bytes32 node, bytes32 label, address owner) public authorised(node) returns(bytes32) {
        bytes32 subnode = keccak256(abi.encodePacked(node, label));
        _setOwner(subnode, owner);
        emit NewOwner(node, label, owner);
        return subnode;
    }

    /**
     * @dev Sets the resolver address for the specified node.
     * @param node The node to update.
     * @param resolver The address of the resolver.
     */
    function setResolver(bytes32 node, address resolver) public authorised(node) {
        emit NewResolver(node, resolver);
        records[node].resolver = resolver;
    }

    /**
     * @dev Sets the TTL for the specified node.
     * @param node The node to update.
     * @param ttl The TTL in seconds.
     */
    function setTTL(bytes32 node, uint64 ttl) public authorised(node) {
        emit NewTTL(node, ttl);
        records[node].ttl = ttl;
    }

    /**
     * @dev Enable or disable approval for a third party ("operator") to manage
     *  all of `msg.sender`'s ENS records. Emits the ApprovalForAll event.
     * @param operator Address to add to the set of authorized operators.
     * @param approved True if the operator is approved, false to revoke approval.
     */
    function setApprovalForAll(address operator, bool approved) external {
        operators[msg.sender][operator] = approved;
        emit ApprovalForAll(msg.sender, operator, approved);
    }

    /**
     * @dev Returns the address that owns the specified node.
     * @param node The specified node.
     * @return address of the owner.
     */
    function owner(bytes32 node) public view returns (address) {
        address addr = records[node].owner;
        if (addr == address(this)) {
            return address(0x0);
        }

        return addr;
    }

    /**
     * @dev Returns the address of the resolver for the specified node.
     * @param node The specified node.
     * @return address of the resolver.
     */
    function resolver(bytes32 node) public view returns (address) {
        return records[node].resolver;
    }

    /**
     * @dev Returns the TTL of a node, and any records associated with it.
     * @param node The specified node.
     * @return ttl of the node.
     */
    function ttl(bytes32 node) public view returns (uint64) {
        return records[node].ttl;
    }

    /**
     * @dev Returns whether a record has been imported to the registry.
     * @param node The specified node.
     * @return Bool if record exists
     */
    function recordExists(bytes32 node) public view returns (bool) {
        return records[node].owner != address(0x0);
    }

    /**
     * @dev Query if an address is an authorized operator for another address.
     * @param owner The address that owns the records.
     * @param operator The address that acts on behalf of the owner.
     * @return True if `operator` is an approved operator for `owner`, false otherwise.
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool) {
        return operators[owner][operator];
    }

    function _setOwner(bytes32 node, address owner) internal {
        records[node].owner = owner;
    }

    function _setResolverAndTTL(bytes32 node, address resolver, uint64 ttl) internal {
        if(resolver != records[node].resolver) {
            records[node].resolver = resolver;
            emit NewResolver(node, resolver);
        }

        if(ttl != records[node].ttl) {
            records[node].ttl = ttl;
            emit NewTTL(node, ttl);
        }
    }
}

// File: @ensdomains/ens/contracts/ENSRegistryWithFallback.sol

pragma solidity ^0.5.0;



/**
 * The ENS registry contract.
 */
contract ENSRegistryWithFallback is ENSRegistry {

    ENS public old;

    /**
     * @dev Constructs a new ENS registrar.
     */
    constructor(ENS _old) public ENSRegistry() {
        old = _old;
    }

    /**
     * @dev Returns the address of the resolver for the specified node.
     * @param node The specified node.
     * @return address of the resolver.
     */
    function resolver(bytes32 node) public view returns (address) {
        if (!recordExists(node)) {
            return old.resolver(node);
        }

        return super.resolver(node);
    }

    /**
     * @dev Returns the address that owns the specified node.
     * @param node The specified node.
     * @return address of the owner.
     */
    function owner(bytes32 node) public view returns (address) {
        if (!recordExists(node)) {
            return old.owner(node);
        }

        return super.owner(node);
    }

    /**
     * @dev Returns the TTL of a node, and any records associated with it.
     * @param node The specified node.
     * @return ttl of the node.
     */
    function ttl(bytes32 node) public view returns (uint64) {
        if (!recordExists(node)) {
            return old.ttl(node);
        }

        return super.ttl(node);
    }

    function _setOwner(bytes32 node, address owner) internal {
        address addr = owner;
        if (addr == address(0x0)) {
            addr = address(this);
        }

        super._setOwner(node, addr);
    }
}

// File: @ensdomains/ethregistrar/contracts/PriceOracle.sol

pragma solidity >=0.4.24;

interface PriceOracle {
    /**
     * @dev Returns the price to register or renew a name.
     * @param name The name being registered or renewed.
     * @param expires When the name presently expires (0 if this is a new registration).
     * @param duration How long the name is being registered or extended for, in seconds.
     * @return The price of this renewal or registration, in wei.
     */
    function price(string calldata name, uint expires, uint duration) external view returns(uint);
}

// File: @ensdomains/ens/contracts/ENS.sol

pragma solidity >=0.4.24;

interface ENS {

    // Logged when the owner of a node assigns a new owner to a subnode.
    event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);

    // Logged when the owner of a node transfers ownership to a new account.
    event Transfer(bytes32 indexed node, address owner);

    // Logged when the resolver for a node changes.
    event NewResolver(bytes32 indexed node, address resolver);

    // Logged when the TTL of a node changes
    event NewTTL(bytes32 indexed node, uint64 ttl);

    // Logged when an operator is added or removed.
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function setRecord(bytes32 node, address owner, address resolver, uint64 ttl) external;
    function setSubnodeRecord(bytes32 node, bytes32 label, address owner, address resolver, uint64 ttl) external;
    function setSubnodeOwner(bytes32 node, bytes32 label, address owner) external returns(bytes32);
    function setResolver(bytes32 node, address resolver) external;
    function setOwner(bytes32 node, address owner) external;
    function setTTL(bytes32 node, uint64 ttl) external;
    function setApprovalForAll(address operator, bool approved) external;
    function owner(bytes32 node) external view returns (address);
    function resolver(bytes32 node) external view returns (address);
    function ttl(bytes32 node) external view returns (uint64);
    function recordExists(bytes32 node) external view returns (bool);
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// File: openzeppelin-solidity/contracts/introspection/IERC165.sol

pragma solidity ^0.5.0;

/**
 * @title IERC165
 * @dev https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
 */
interface IERC165 {
    /**
     * @notice Query if a contract implements an interface
     * @param interfaceId The interface identifier, as specified in ERC-165
     * @dev Interface identification is specified in ERC-165. This function
     * uses less than 30,000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721.sol

pragma solidity ^0.5.0;


/**
 * @title ERC721 Non-Fungible Token Standard basic interface
 * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
 */
contract IERC721 is IERC165 {
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function balanceOf(address owner) public view returns (uint256 balance);
    function ownerOf(uint256 tokenId) public view returns (address owner);

    function approve(address to, uint256 tokenId) public;
    function getApproved(uint256 tokenId) public view returns (address operator);

    function setApprovalForAll(address operator, bool _approved) public;
    function isApprovedForAll(address owner, address operator) public view returns (bool);

    function transferFrom(address from, address to, uint256 tokenId) public;
    function safeTransferFrom(address from, address to, uint256 tokenId) public;

    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public;
}

// File: openzeppelin-solidity/contracts/ownership/Ownable.sol

pragma solidity ^0.5.0;

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    constructor () internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
    }

    /**
     * @return the address of the owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(isOwner());
        _;
    }

    /**
     * @return true if `msg.sender` is the owner of the contract.
     */
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     * @notice Renouncing to ownership will leave the contract without an owner.
     * It will not be possible to call the functions with the `onlyOwner`
     * modifier anymore.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0));
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: @ensdomains/ethregistrar/contracts/BaseRegistrar.sol

pragma solidity >=0.4.24;




contract BaseRegistrar is IERC721, Ownable {
    uint constant public GRACE_PERIOD = 90 days;

    event ControllerAdded(address indexed controller);
    event ControllerRemoved(address indexed controller);
    event NameMigrated(uint256 indexed id, address indexed owner, uint expires);
    event NameRegistered(uint256 indexed id, address indexed owner, uint expires);
    event NameRenewed(uint256 indexed id, uint expires);

    // The ENS registry
    ENS public ens;

    // The namehash of the TLD this registrar owns (eg, .eth)
    bytes32 public baseNode;

    // A map of addresses that are authorised to register and renew names.
    mapping(address=>bool) public controllers;

    // Authorises a controller, who can register and renew domains.
    function addController(address controller) external;

    // Revoke controller permission for an address.
    function removeController(address controller) external;

    // Set the resolver for the TLD this registrar manages.
    function setResolver(address resolver) external;

    // Returns the expiration timestamp of the specified label hash.
    function nameExpires(uint256 id) external view returns(uint);

    // Returns true iff the specified name is available for registration.
    function available(uint256 id) public view returns(bool);

    /**
     * @dev Register a name.
     */
    function register(uint256 id, address owner, uint duration) external returns(uint);

    function renew(uint256 id, uint duration) external returns(uint);

    /**
     * @dev Reclaim ownership of a name in ENS, if you own it in the registrar.
     */
    function reclaim(uint256 id, address owner) external;
}

// File: @ensdomains/ethregistrar/contracts/StringUtils.sol

pragma solidity >=0.4.24;

library StringUtils {
    /**
     * @dev Returns the length of a given string
     *
     * @param s The string to measure the length of
     * @return The length of the input string
     */
    function strlen(string memory s) internal pure returns (uint) {
        uint len;
        uint i = 0;
        uint bytelength = bytes(s).length;
        for(len = 0; i < bytelength; len++) {
            byte b = bytes(s)[i];
            if(b < 0x80) {
                i += 1;
            } else if (b < 0xE0) {
                i += 2;
            } else if (b < 0xF0) {
                i += 3;
            } else if (b < 0xF8) {
                i += 4;
            } else if (b < 0xFC) {
                i += 5;
            } else {
                i += 6;
            }
        }
        return len;
    }
}

// File: @ensdomains/resolver/contracts/Resolver.sol

pragma solidity >=0.4.25;

/**
 * A generic resolver interface which includes all the functions including the ones deprecated
 */
interface Resolver{
    event AddrChanged(bytes32 indexed node, address a);
    event AddressChanged(bytes32 indexed node, uint coinType, bytes newAddress);
    event NameChanged(bytes32 indexed node, string name);
    event ABIChanged(bytes32 indexed node, uint256 indexed contentType);
    event PubkeyChanged(bytes32 indexed node, bytes32 x, bytes32 y);
    event TextChanged(bytes32 indexed node, string indexed indexedKey, string key);
    event ContenthashChanged(bytes32 indexed node, bytes hash);
    /* Deprecated events */
    event ContentChanged(bytes32 indexed node, bytes32 hash);

    function ABI(bytes32 node, uint256 contentTypes) external view returns (uint256, bytes memory);
    function addr(bytes32 node) external view returns (address);
    function addr(bytes32 node, uint coinType) external view returns(bytes memory);
    function contenthash(bytes32 node) external view returns (bytes memory);
    function dnsrr(bytes32 node) external view returns (bytes memory);
    function name(bytes32 node) external view returns (string memory);
    function pubkey(bytes32 node) external view returns (bytes32 x, bytes32 y);
    function text(bytes32 node, string calldata key) external view returns (string memory);
    function interfaceImplementer(bytes32 node, bytes4 interfaceID) external view returns (address);

    function setABI(bytes32 node, uint256 contentType, bytes calldata data) external;
    function setAddr(bytes32 node, address addr) external;
    function setAddr(bytes32 node, uint coinType, bytes calldata a) external;
    function setContenthash(bytes32 node, bytes calldata hash) external;
    function setDnsrr(bytes32 node, bytes calldata data) external;
    function setName(bytes32 node, string calldata _name) external;
    function setPubkey(bytes32 node, bytes32 x, bytes32 y) external;
    function setText(bytes32 node, string calldata key, string calldata value) external;
    function setInterface(bytes32 node, bytes4 interfaceID, address implementer) external;

    function supportsInterface(bytes4 interfaceID) external pure returns (bool);

    /* Deprecated functions */
    function content(bytes32 node) external view returns (bytes32);
    function multihash(bytes32 node) external view returns (bytes memory);
    function setContent(bytes32 node, bytes32 hash) external;
    function setMultihash(bytes32 node, bytes calldata hash) external;
}

// File: @ensdomains/ethregistrar/contracts/ETHRegistrarController.sol

pragma solidity ^0.5.0;






/**
 * @dev A registrar controller for registering and renewing names at fixed cost.
 */
contract ETHRegistrarController is Ownable {
    using StringUtils for *;

    uint constant public MIN_REGISTRATION_DURATION = 28 days;

    bytes4 constant private INTERFACE_META_ID = bytes4(keccak256("supportsInterface(bytes4)"));
    bytes4 constant private COMMITMENT_CONTROLLER_ID = bytes4(
        keccak256("rentPrice(string,uint256)") ^
        keccak256("available(string)") ^
        keccak256("makeCommitment(string,address,bytes32)") ^
        keccak256("commit(bytes32)") ^
        keccak256("register(string,address,uint256,bytes32)") ^
        keccak256("renew(string,uint256)")
    );

    bytes4 constant private COMMITMENT_WITH_CONFIG_CONTROLLER_ID = bytes4(
        keccak256("registerWithConfig(string,address,uint256,bytes32,address,address)") ^
        keccak256("makeCommitmentWithConfig(string,address,bytes32,address,address)")
    );

    BaseRegistrar base;
    PriceOracle prices;
    uint public minCommitmentAge;
    uint public maxCommitmentAge;

    mapping(bytes32=>uint) public commitments;

    event NameRegistered(string name, bytes32 indexed label, address indexed owner, uint cost, uint expires);
    event NameRenewed(string name, bytes32 indexed label, uint cost, uint expires);
    event NewPriceOracle(address indexed oracle);

    constructor(BaseRegistrar _base, PriceOracle _prices, uint _minCommitmentAge, uint _maxCommitmentAge) public {
        require(_maxCommitmentAge > _minCommitmentAge);

        base = _base;
        prices = _prices;
        minCommitmentAge = _minCommitmentAge;
        maxCommitmentAge = _maxCommitmentAge;
    }

    function rentPrice(string memory name, uint duration) view public returns(uint) {
        bytes32 hash = keccak256(bytes(name));
        return prices.price(name, base.nameExpires(uint256(hash)), duration);
    }

    function valid(string memory name) public pure returns(bool) {
        return name.strlen() >= 3;
    }

    function available(string memory name) public view returns(bool) {
        bytes32 label = keccak256(bytes(name));
        return valid(name) && base.available(uint256(label));
    }

    function makeCommitment(string memory name, address owner, bytes32 secret) pure public returns(bytes32) {
        return makeCommitmentWithConfig(name, owner, secret, address(0), address(0));
    }

    function makeCommitmentWithConfig(string memory name, address owner, bytes32 secret, address resolver, address addr) pure public returns(bytes32) {
        bytes32 label = keccak256(bytes(name));
        if (resolver == address(0) && addr == address(0)) {
            return keccak256(abi.encodePacked(label, owner, secret));
        }
        require(resolver != address(0));
        return keccak256(abi.encodePacked(label, owner, resolver, addr, secret));
    }

    function commit(bytes32 commitment) public {
        require(commitments[commitment] + maxCommitmentAge < now);
        commitments[commitment] = now;
    }

    function register(string calldata name, address owner, uint duration, bytes32 secret) external payable {
      registerWithConfig(name, owner, duration, secret, address(0), address(0));
    }

    function registerWithConfig(string memory name, address owner, uint duration, bytes32 secret, address resolver, address addr) public payable {
        bytes32 commitment = makeCommitmentWithConfig(name, owner, secret, resolver, addr);
        uint cost = _consumeCommitment(name, duration, commitment);

        bytes32 label = keccak256(bytes(name));
        uint256 tokenId = uint256(label);

        uint expires;
        if(resolver != address(0)) {
            // Set this contract as the (temporary) owner, giving it
            // permission to set up the resolver.
            expires = base.register(tokenId, address(this), duration);

            // The nodehash of this label
            bytes32 nodehash = keccak256(abi.encodePacked(base.baseNode(), label));

            // Set the resolver
            base.ens().setResolver(nodehash, resolver);

            // Configure the resolver
            if (addr != address(0)) {
                Resolver(resolver).setAddr(nodehash, addr);
            }

            // Now transfer full ownership to the expeceted owner
            base.reclaim(tokenId, owner);
            base.transferFrom(address(this), owner, tokenId);
        } else {
            require(addr == address(0));
            expires = base.register(tokenId, owner, duration);
        }

        emit NameRegistered(name, label, owner, cost, expires);

        // Refund any extra payment
        if(msg.value > cost) {
            msg.sender.transfer(msg.value - cost);
        }
    }

    function renew(string calldata name, uint duration) external payable {
        uint cost = rentPrice(name, duration);
        require(msg.value >= cost);

        bytes32 label = keccak256(bytes(name));
        uint expires = base.renew(uint256(label), duration);

        if(msg.value > cost) {
            msg.sender.transfer(msg.value - cost);
        }

        emit NameRenewed(name, label, cost, expires);
    }

    function setPriceOracle(PriceOracle _prices) public onlyOwner {
        prices = _prices;
        emit NewPriceOracle(address(prices));
    }

    function setCommitmentAges(uint _minCommitmentAge, uint _maxCommitmentAge) public onlyOwner {
        minCommitmentAge = _minCommitmentAge;
        maxCommitmentAge = _maxCommitmentAge;
    }

    function withdraw() public onlyOwner {
        msg.sender.transfer(address(this).balance);
    }

    function supportsInterface(bytes4 interfaceID) external pure returns (bool) {
        return interfaceID == INTERFACE_META_ID ||
               interfaceID == COMMITMENT_CONTROLLER_ID ||
               interfaceID == COMMITMENT_WITH_CONFIG_CONTROLLER_ID;
    }

    function _consumeCommitment(string memory name, uint duration, bytes32 commitment) internal returns (uint256) {
        // Require a valid commitment
        require(commitments[commitment] + minCommitmentAge <= now);

        // If the commitment is too old, or the name is registered, stop
        require(commitments[commitment] + maxCommitmentAge > now);
        require(available(name));

        delete(commitments[commitment]);

        uint cost = rentPrice(name, duration);
        require(duration >= MIN_REGISTRATION_DURATION);
        require(msg.value >= cost);

        return cost;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        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;
    }
}
pragma solidity >=0.8.4;
import "./SafeMath.sol";
import "./StablePriceOracle.sol";
contract ExponentialPremiumPriceOracle is StablePriceOracle {
    uint256 constant GRACE_PERIOD = 90 days;
    uint256 immutable startPremium;
    uint256 immutable endValue;
    constructor(
        AggregatorInterface _usdOracle,
        uint256[] memory _rentPrices,
        uint256 _startPremium,
        uint256 totalDays
    ) StablePriceOracle(_usdOracle, _rentPrices) {
        startPremium = _startPremium;
        endValue = _startPremium >> totalDays;
    }
    uint256 constant PRECISION = 1e18;
    uint256 constant bit1 = 999989423469314432; // 0.5 ^ 1/65536 * (10 ** 18)
    uint256 constant bit2 = 999978847050491904; // 0.5 ^ 2/65536 * (10 ** 18)
    uint256 constant bit3 = 999957694548431104;
    uint256 constant bit4 = 999915390886613504;
    uint256 constant bit5 = 999830788931929088;
    uint256 constant bit6 = 999661606496243712;
    uint256 constant bit7 = 999323327502650752;
    uint256 constant bit8 = 998647112890970240;
    uint256 constant bit9 = 997296056085470080;
    uint256 constant bit10 = 994599423483633152;
    uint256 constant bit11 = 989228013193975424;
    uint256 constant bit12 = 978572062087700096;
    uint256 constant bit13 = 957603280698573696;
    uint256 constant bit14 = 917004043204671232;
    uint256 constant bit15 = 840896415253714560;
    uint256 constant bit16 = 707106781186547584;
    /**
     * @dev Returns the pricing premium in internal base units.
     */
    function _premium(
        string memory,
        uint256 expires,
        uint256
    ) internal view override returns (uint256) {
        expires = expires + GRACE_PERIOD;
        if (expires > block.timestamp) {
            return 0;
        }
        uint256 elapsed = block.timestamp - expires;
        uint256 premium = decayedPremium(startPremium, elapsed);
        if (premium >= endValue) {
            return premium - endValue;
        }
        return 0;
    }
    /**
     * @dev Returns the premium price at current time elapsed
     * @param startPremium starting price
     * @param elapsed time past since expiry
     */
    function decayedPremium(uint256 startPremium, uint256 elapsed)
        public
        pure
        returns (uint256)
    {
        uint256 daysPast = (elapsed * PRECISION) / 1 days;
        uint256 intDays = daysPast / PRECISION;
        uint256 premium = startPremium >> intDays;
        uint256 partDay = (daysPast - intDays * PRECISION);
        uint256 fraction = (partDay * (2**16)) / PRECISION;
        uint256 totalPremium = addFractionalPremium(fraction, premium);
        return totalPremium;
    }
    function addFractionalPremium(uint256 fraction, uint256 premium)
        internal
        pure
        returns (uint256)
    {
        if (fraction & (1 << 0) != 0) {
            premium = (premium * bit1) / PRECISION;
        }
        if (fraction & (1 << 1) != 0) {
            premium = (premium * bit2) / PRECISION;
        }
        if (fraction & (1 << 2) != 0) {
            premium = (premium * bit3) / PRECISION;
        }
        if (fraction & (1 << 3) != 0) {
            premium = (premium * bit4) / PRECISION;
        }
        if (fraction & (1 << 4) != 0) {
            premium = (premium * bit5) / PRECISION;
        }
        if (fraction & (1 << 5) != 0) {
            premium = (premium * bit6) / PRECISION;
        }
        if (fraction & (1 << 6) != 0) {
            premium = (premium * bit7) / PRECISION;
        }
        if (fraction & (1 << 7) != 0) {
            premium = (premium * bit8) / PRECISION;
        }
        if (fraction & (1 << 8) != 0) {
            premium = (premium * bit9) / PRECISION;
        }
        if (fraction & (1 << 9) != 0) {
            premium = (premium * bit10) / PRECISION;
        }
        if (fraction & (1 << 10) != 0) {
            premium = (premium * bit11) / PRECISION;
        }
        if (fraction & (1 << 11) != 0) {
            premium = (premium * bit12) / PRECISION;
        }
        if (fraction & (1 << 12) != 0) {
            premium = (premium * bit13) / PRECISION;
        }
        if (fraction & (1 << 13) != 0) {
            premium = (premium * bit14) / PRECISION;
        }
        if (fraction & (1 << 14) != 0) {
            premium = (premium * bit15) / PRECISION;
        }
        if (fraction & (1 << 15) != 0) {
            premium = (premium * bit16) / PRECISION;
        }
        return premium;
    }
    function supportsInterface(bytes4 interfaceID)
        public
        view
        virtual
        override
        returns (bool)
    {
        return super.supportsInterface(interfaceID);
    }
}
pragma solidity >=0.8.4;
interface PriceOracle {
    /**
     * @dev Returns the price to register or renew a name.
     * @param name The name being registered or renewed.
     * @param expires When the name presently expires (0 if this is a new registration).
     * @param duration How long the name is being registered or extended for, in seconds.
     * @return The price of this renewal or registration, in wei.
     */
    function price(string calldata name, uint expires, uint duration) external view returns(uint);
}
pragma solidity >=0.8.4;
/**
 * @title SafeMath
 * @dev Unsigned math operations with safety checks that revert on error
 */
library SafeMath {
    /**
    * @dev Multiplies two unsigned integers, reverts on overflow.
    */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b);
        return c;
    }
    /**
    * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
    */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }
    /**
    * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
    */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;
        return c;
    }
    /**
    * @dev Adds two unsigned integers, reverts on overflow.
    */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);
        return c;
    }
    /**
    * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
    * reverts when dividing by zero.
    */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }
}
pragma solidity >=0.8.4;
import "./PriceOracle.sol";
import "./SafeMath.sol";
import "./StringUtils.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
interface AggregatorInterface {
    function latestAnswer() external view returns (int256);
}
// StablePriceOracle sets a price in USD, based on an oracle.
contract StablePriceOracle is Ownable, PriceOracle {
    using SafeMath for *;
    using StringUtils for *;
    // Rent in base price units by length. Element 0 is for 1-length names, and so on.
    uint256[] public rentPrices;
    // Oracle address
    AggregatorInterface public immutable usdOracle;
    event OracleChanged(address oracle);
    event RentPriceChanged(uint256[] prices);
    bytes4 private constant INTERFACE_META_ID =
        bytes4(keccak256("supportsInterface(bytes4)"));
    bytes4 private constant ORACLE_ID =
        bytes4(
            keccak256("price(string,uint256,uint256)") ^
                keccak256("premium(string,uint256,uint256)")
        );
    constructor(AggregatorInterface _usdOracle, uint256[] memory _rentPrices)
        public
    {
        usdOracle = _usdOracle;
        setPrices(_rentPrices);
    }
    function price(
        string calldata name,
        uint256 expires,
        uint256 duration
    ) external view override returns (uint256) {
        uint256 len = name.strlen();
        if (len > rentPrices.length) {
            len = rentPrices.length;
        }
        require(len > 0);
        uint256 basePrice = rentPrices[len - 1].mul(duration);
        basePrice = basePrice.add(_premium(name, expires, duration));
        return attoUSDToWei(basePrice);
    }
    /**
     * @dev Sets rent prices.
     * @param _rentPrices The price array. Each element corresponds to a specific
     *                    name length; names longer than the length of the array
     *                    default to the price of the last element. Values are
     *                    in base price units, equal to one attodollar (1e-18
     *                    dollar) each.
     */
    function setPrices(uint256[] memory _rentPrices) public onlyOwner {
        rentPrices = _rentPrices;
        emit RentPriceChanged(_rentPrices);
    }
    /**
     * @dev Returns the pricing premium in wei.
     */
    function premium(
        string calldata name,
        uint256 expires,
        uint256 duration
    ) external view returns (uint256) {
        uint256 weiPrice = attoUSDToWei(_premium(name, expires, duration));
        return weiPrice;
    }
    /**
     * @dev Returns the pricing premium in internal base units.
     */
    function _premium(
        string memory name,
        uint256 expires,
        uint256 duration
    ) internal view virtual returns (uint256) {
        return 0;
    }
    function attoUSDToWei(uint256 amount) internal view returns (uint256) {
        uint256 ethPrice = uint256(usdOracle.latestAnswer()); //2
        return amount.mul(1e8).div(ethPrice);
    }
    function weiToAttoUSD(uint256 amount) internal view returns (uint256) {
        uint256 ethPrice = uint256(usdOracle.latestAnswer());
        return amount.mul(ethPrice).div(1e8);
    }
    function supportsInterface(bytes4 interfaceID)
        public
        view
        virtual
        returns (bool)
    {
        return interfaceID == INTERFACE_META_ID || interfaceID == ORACLE_ID;
    }
}
pragma solidity >=0.8.4;
library StringUtils {
    /**
     * @dev Returns the length of a given string
     *
     * @param s The string to measure the length of
     * @return The length of the input string
     */
    function strlen(string memory s) internal pure returns (uint) {
        uint len;
        uint i = 0;
        uint bytelength = bytes(s).length;
        for(len = 0; i < bytelength; len++) {
            bytes1 b = bytes(s)[i];
            if(b < 0x80) {
                i += 1;
            } else if (b < 0xE0) {
                i += 2;
            } else if (b < 0xF0) {
                i += 3;
            } else if (b < 0xF8) {
                i += 4;
            } else if (b < 0xFC) {
                i += 5;
            } else {
                i += 6;
            }
        }
        return len;
    }
}

pragma solidity 0.6.6;


/**
 * @title The Owned contract
 * @notice A contract with helpers for basic contract ownership.
 */
contract Owned {

  address payable public owner;
  address private pendingOwner;

  event OwnershipTransferRequested(
    address indexed from,
    address indexed to
  );
  event OwnershipTransferred(
    address indexed from,
    address indexed to
  );

  constructor() public {
    owner = msg.sender;
  }

  /**
   * @dev Allows an owner to begin transferring ownership to a new address,
   * pending.
   */
  function transferOwnership(address _to)
    external
    onlyOwner()
  {
    pendingOwner = _to;

    emit OwnershipTransferRequested(owner, _to);
  }

  /**
   * @dev Allows an ownership transfer to be completed by the recipient.
   */
  function acceptOwnership()
    external
  {
    require(msg.sender == pendingOwner, "Must be proposed owner");

    address oldOwner = owner;
    owner = msg.sender;
    pendingOwner = address(0);

    emit OwnershipTransferred(oldOwner, msg.sender);
  }

  /**
   * @dev Reverts if called by anyone other than the contract owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner, "Only callable by owner");
    _;
  }

}

interface AggregatorInterface {
  function latestAnswer() external view returns (int256);
  function latestTimestamp() external view returns (uint256);
  function latestRound() external view returns (uint256);
  function getAnswer(uint256 roundId) external view returns (int256);
  function getTimestamp(uint256 roundId) external view returns (uint256);

  event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
  event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
}

interface AggregatorV3Interface {

  function decimals() external view returns (uint8);
  function description() external view returns (string memory);
  function version() external view returns (uint256);

  // getRoundData and latestRoundData should both raise "No data present"
  // if they do not have data to report, instead of returning unset values
  // which could be misinterpreted as actual reported values.
  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

}

interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
{
}

/**
 * @title A trusted proxy for updating where current answers are read from
 * @notice This contract provides a consistent address for the
 * CurrentAnwerInterface but delegates where it reads from to the owner, who is
 * trusted to update it.
 */
contract AggregatorProxy is AggregatorV2V3Interface, Owned {

  struct Phase {
    uint16 id;
    AggregatorV2V3Interface aggregator;
  }
  Phase private currentPhase;
  AggregatorV2V3Interface public proposedAggregator;
  mapping(uint16 => AggregatorV2V3Interface) public phaseAggregators;

  uint256 constant private PHASE_OFFSET = 64;
  uint256 constant private PHASE_SIZE = 16;
  uint256 constant private MAX_ID = 2**(PHASE_OFFSET+PHASE_SIZE) - 1;

  constructor(address _aggregator) public Owned() {
    setAggregator(_aggregator);
  }

  /**
   * @notice Reads the current answer from aggregator delegated to.
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestAnswer()
    public
    view
    virtual
    override
    returns (int256 answer)
  {
    return currentPhase.aggregator.latestAnswer();
  }

  /**
   * @notice Reads the last updated height from aggregator delegated to.
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestTimestamp()
    public
    view
    virtual
    override
    returns (uint256 updatedAt)
  {
    return currentPhase.aggregator.latestTimestamp();
  }

  /**
   * @notice get past rounds answers
   * @param _roundId the answer number to retrieve the answer for
   *
   * @dev #[deprecated] Use getRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended getRoundData
   * instead which includes better verification information.
   */
  function getAnswer(uint256 _roundId)
    public
    view
    virtual
    override
    returns (int256 answer)
  {
    if (_roundId > MAX_ID) return 0;

    (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);
    AggregatorV2V3Interface aggregator = phaseAggregators[phaseId];
    if (address(aggregator) == address(0)) return 0;

    return aggregator.getAnswer(aggregatorRoundId);
  }

  /**
   * @notice get block timestamp when an answer was last updated
   * @param _roundId the answer number to retrieve the updated timestamp for
   *
   * @dev #[deprecated] Use getRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended getRoundData
   * instead which includes better verification information.
   */
  function getTimestamp(uint256 _roundId)
    public
    view
    virtual
    override
    returns (uint256 updatedAt)
  {
    if (_roundId > MAX_ID) return 0;

    (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);
    AggregatorV2V3Interface aggregator = phaseAggregators[phaseId];
    if (address(aggregator) == address(0)) return 0;

    return aggregator.getTimestamp(aggregatorRoundId);
  }

  /**
   * @notice get the latest completed round where the answer was updated. This
   * ID includes the proxy's phase, to make sure round IDs increase even when
   * switching to a newly deployed aggregator.
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestRound()
    public
    view
    virtual
    override
    returns (uint256 roundId)
  {
    Phase memory phase = currentPhase; // cache storage reads
    return addPhase(phase.id, uint64(phase.aggregator.latestRound()));
  }

  /**
   * @notice get data about a round. Consumers are encouraged to check
   * that they're receiving fresh data by inspecting the updatedAt and
   * answeredInRound return values.
   * Note that different underlying implementations of AggregatorV3Interface
   * have slightly different semantics for some of the return values. Consumers
   * should determine what implementations they expect to receive
   * data from and validate that they can properly handle return data from all
   * of them.
   * @param _roundId the requested round ID as presented through the proxy, this
   * is made up of the aggregator's round ID with the phase ID encoded in the
   * two highest order bytes
   * @return roundId is the round ID from the aggregator for which the data was
   * retrieved combined with an phase to ensure that round IDs get larger as
   * time moves forward.
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @dev Note that answer and updatedAt may change between queries.
   */
  function getRoundData(uint80 _roundId)
    public
    view
    virtual
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);

    (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 ansIn
    ) = phaseAggregators[phaseId].getRoundData(aggregatorRoundId);

    return addPhaseIds(roundId, answer, startedAt, updatedAt, ansIn, phaseId);
  }

  /**
   * @notice get data about the latest round. Consumers are encouraged to check
   * that they're receiving fresh data by inspecting the updatedAt and
   * answeredInRound return values.
   * Note that different underlying implementations of AggregatorV3Interface
   * have slightly different semantics for some of the return values. Consumers
   * should determine what implementations they expect to receive
   * data from and validate that they can properly handle return data from all
   * of them.
   * @return roundId is the round ID from the aggregator for which the data was
   * retrieved combined with an phase to ensure that round IDs get larger as
   * time moves forward.
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @dev Note that answer and updatedAt may change between queries.
   */
  function latestRoundData()
    public
    view
    virtual
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    Phase memory current = currentPhase; // cache storage reads

    (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 ansIn
    ) = current.aggregator.latestRoundData();

    return addPhaseIds(roundId, answer, startedAt, updatedAt, ansIn, current.id);
  }

  /**
   * @notice Used if an aggregator contract has been proposed.
   * @param _roundId the round ID to retrieve the round data for
   * @return roundId is the round ID for which data was retrieved
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
  */
  function proposedGetRoundData(uint80 _roundId)
    public
    view
    virtual
    hasProposal()
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return proposedAggregator.getRoundData(_roundId);
  }

  /**
   * @notice Used if an aggregator contract has been proposed.
   * @return roundId is the round ID for which data was retrieved
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
  */
  function proposedLatestRoundData()
    public
    view
    virtual
    hasProposal()
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return proposedAggregator.latestRoundData();
  }

  /**
   * @notice returns the current phase's aggregator address.
   */
  function aggregator()
    external
    view
    returns (address)
  {
    return address(currentPhase.aggregator);
  }

  /**
   * @notice returns the current phase's ID.
   */
  function phaseId()
    external
    view
    returns (uint16)
  {
    return currentPhase.id;
  }

  /**
   * @notice represents the number of decimals the aggregator responses represent.
   */
  function decimals()
    external
    view
    override
    returns (uint8)
  {
    return currentPhase.aggregator.decimals();
  }

  /**
   * @notice the version number representing the type of aggregator the proxy
   * points to.
   */
  function version()
    external
    view
    override
    returns (uint256)
  {
    return currentPhase.aggregator.version();
  }

  /**
   * @notice returns the description of the aggregator the proxy points to.
   */
  function description()
    external
    view
    override
    returns (string memory)
  {
    return currentPhase.aggregator.description();
  }

  /**
   * @notice Allows the owner to propose a new address for the aggregator
   * @param _aggregator The new address for the aggregator contract
   */
  function proposeAggregator(address _aggregator)
    external
    onlyOwner()
  {
    proposedAggregator = AggregatorV2V3Interface(_aggregator);
  }

  /**
   * @notice Allows the owner to confirm and change the address
   * to the proposed aggregator
   * @dev Reverts if the given address doesn't match what was previously
   * proposed
   * @param _aggregator The new address for the aggregator contract
   */
  function confirmAggregator(address _aggregator)
    external
    onlyOwner()
  {
    require(_aggregator == address(proposedAggregator), "Invalid proposed aggregator");
    delete proposedAggregator;
    setAggregator(_aggregator);
  }


  /*
   * Internal
   */

  function setAggregator(address _aggregator)
    internal
  {
    uint16 id = currentPhase.id + 1;
    currentPhase = Phase(id, AggregatorV2V3Interface(_aggregator));
    phaseAggregators[id] = AggregatorV2V3Interface(_aggregator);
  }

  function addPhase(
    uint16 _phase,
    uint64 _originalId
  )
    internal
    view
    returns (uint80)
  {
    return uint80(uint256(_phase) << PHASE_OFFSET | _originalId);
  }

  function parseIds(
    uint256 _roundId
  )
    internal
    view
    returns (uint16, uint64)
  {
    uint16 phaseId = uint16(_roundId >> PHASE_OFFSET);
    uint64 aggregatorRoundId = uint64(_roundId);

    return (phaseId, aggregatorRoundId);
  }

  function addPhaseIds(
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound,
      uint16 phaseId
  )
    internal
    view
    returns (uint80, int256, uint256, uint256, uint80)
  {
    return (
      addPhase(phaseId, uint64(roundId)),
      answer,
      startedAt,
      updatedAt,
      addPhase(phaseId, uint64(answeredInRound))
    );
  }

  /*
   * Modifiers
   */

  modifier hasProposal() {
    require(address(proposedAggregator) != address(0), "No proposed aggregator present");
    _;
  }

}

interface AccessControllerInterface {
  function hasAccess(address user, bytes calldata data) external view returns (bool);
}

/**
 * @title External Access Controlled Aggregator Proxy
 * @notice A trusted proxy for updating where current answers are read from
 * @notice This contract provides a consistent address for the
 * Aggregator and AggregatorV3Interface but delegates where it reads from to the owner, who is
 * trusted to update it.
 * @notice Only access enabled addresses are allowed to access getters for
 * aggregated answers and round information.
 */
contract EACAggregatorProxy is AggregatorProxy {

  AccessControllerInterface public accessController;

  constructor(
    address _aggregator,
    address _accessController
  )
    public
    AggregatorProxy(_aggregator)
  {
    setController(_accessController);
  }

  /**
   * @notice Allows the owner to update the accessController contract address.
   * @param _accessController The new address for the accessController contract
   */
  function setController(address _accessController)
    public
    onlyOwner()
  {
    accessController = AccessControllerInterface(_accessController);
  }

  /**
   * @notice Reads the current answer from aggregator delegated to.
   * @dev overridden function to add the checkAccess() modifier
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestAnswer()
    public
    view
    override
    checkAccess()
    returns (int256)
  {
    return super.latestAnswer();
  }

  /**
   * @notice get the latest completed round where the answer was updated. This
   * ID includes the proxy's phase, to make sure round IDs increase even when
   * switching to a newly deployed aggregator.
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestTimestamp()
    public
    view
    override
    checkAccess()
    returns (uint256)
  {
    return super.latestTimestamp();
  }

  /**
   * @notice get past rounds answers
   * @param _roundId the answer number to retrieve the answer for
   * @dev overridden function to add the checkAccess() modifier
   *
   * @dev #[deprecated] Use getRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended getRoundData
   * instead which includes better verification information.
   */
  function getAnswer(uint256 _roundId)
    public
    view
    override
    checkAccess()
    returns (int256)
  {
    return super.getAnswer(_roundId);
  }

  /**
   * @notice get block timestamp when an answer was last updated
   * @param _roundId the answer number to retrieve the updated timestamp for
   * @dev overridden function to add the checkAccess() modifier
   *
   * @dev #[deprecated] Use getRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended getRoundData
   * instead which includes better verification information.
   */
  function getTimestamp(uint256 _roundId)
    public
    view
    override
    checkAccess()
    returns (uint256)
  {
    return super.getTimestamp(_roundId);
  }

  /**
   * @notice get the latest completed round where the answer was updated
   * @dev overridden function to add the checkAccess() modifier
   *
   * @dev #[deprecated] Use latestRoundData instead. This does not error if no
   * answer has been reached, it will simply return 0. Either wait to point to
   * an already answered Aggregator or use the recommended latestRoundData
   * instead which includes better verification information.
   */
  function latestRound()
    public
    view
    override
    checkAccess()
    returns (uint256)
  {
    return super.latestRound();
  }

  /**
   * @notice get data about a round. Consumers are encouraged to check
   * that they're receiving fresh data by inspecting the updatedAt and
   * answeredInRound return values.
   * Note that different underlying implementations of AggregatorV3Interface
   * have slightly different semantics for some of the return values. Consumers
   * should determine what implementations they expect to receive
   * data from and validate that they can properly handle return data from all
   * of them.
   * @param _roundId the round ID to retrieve the round data for
   * @return roundId is the round ID from the aggregator for which the data was
   * retrieved combined with a phase to ensure that round IDs get larger as
   * time moves forward.
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @dev Note that answer and updatedAt may change between queries.
   */
  function getRoundData(uint80 _roundId)
    public
    view
    checkAccess()
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.getRoundData(_roundId);
  }

  /**
   * @notice get data about the latest round. Consumers are encouraged to check
   * that they're receiving fresh data by inspecting the updatedAt and
   * answeredInRound return values.
   * Note that different underlying implementations of AggregatorV3Interface
   * have slightly different semantics for some of the return values. Consumers
   * should determine what implementations they expect to receive
   * data from and validate that they can properly handle return data from all
   * of them.
   * @return roundId is the round ID from the aggregator for which the data was
   * retrieved combined with a phase to ensure that round IDs get larger as
   * time moves forward.
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @dev Note that answer and updatedAt may change between queries.
   */
  function latestRoundData()
    public
    view
    checkAccess()
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.latestRoundData();
  }

  /**
   * @notice Used if an aggregator contract has been proposed.
   * @param _roundId the round ID to retrieve the round data for
   * @return roundId is the round ID for which data was retrieved
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
  */
  function proposedGetRoundData(uint80 _roundId)
    public
    view
    checkAccess()
    hasProposal()
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.proposedGetRoundData(_roundId);
  }

  /**
   * @notice Used if an aggregator contract has been proposed.
   * @return roundId is the round ID for which data was retrieved
   * @return answer is the answer for the given round
   * @return startedAt is the timestamp when the round was started.
   * (Only some AggregatorV3Interface implementations return meaningful values)
   * @return updatedAt is the timestamp when the round last was updated (i.e.
   * answer was last computed)
   * @return answeredInRound is the round ID of the round in which the answer
   * was computed.
  */
  function proposedLatestRoundData()
    public
    view
    checkAccess()
    hasProposal()
    override
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.proposedLatestRoundData();
  }

  /**
   * @dev reverts if the caller does not have access by the accessController
   * contract or is the contract itself.
   */
  modifier checkAccess() {
    AccessControllerInterface ac = accessController;
    require(address(ac) == address(0) || ac.hasAccess(msg.sender, msg.data), "No access");
    _;
  }
}

// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./OffchainAggregator.sol";
import "./SimpleReadAccessController.sol";
/**
 * @notice Wrapper of OffchainAggregator which checks read access on Aggregator-interface methods
 */
contract AccessControlledOffchainAggregator is OffchainAggregator, SimpleReadAccessController {
  constructor(
    uint32 _maximumGasPrice,
    uint32 _reasonableGasPrice,
    uint32 _microLinkPerEth,
    uint32 _linkGweiPerObservation,
    uint32 _linkGweiPerTransmission,
    LinkTokenInterface _link,
    int192 _minAnswer,
    int192 _maxAnswer,
    AccessControllerInterface _billingAccessController,
    AccessControllerInterface _requesterAccessController,
    uint8 _decimals,
    string memory description
  )
    OffchainAggregator(
      _maximumGasPrice,
      _reasonableGasPrice,
      _microLinkPerEth,
      _linkGweiPerObservation,
      _linkGweiPerTransmission,
      _link,
      _minAnswer,
      _maxAnswer,
      _billingAccessController,
      _requesterAccessController,
      _decimals,
      description
    ) {
    }
  /*
   * Versioning
   */
  function typeAndVersion()
    external
    override
    pure
    virtual
    returns (string memory)
  {
    return "AccessControlledOffchainAggregator 4.0.0";
  }
  /*
   * v2 Aggregator interface
   */
  /// @inheritdoc OffchainAggregator
  function latestAnswer()
    public
    override
    view
    checkAccess()
    returns (int256)
  {
    return super.latestAnswer();
  }
  /// @inheritdoc OffchainAggregator
  function latestTimestamp()
    public
    override
    view
    checkAccess()
    returns (uint256)
  {
    return super.latestTimestamp();
  }
  /// @inheritdoc OffchainAggregator
  function latestRound()
    public
    override
    view
    checkAccess()
    returns (uint256)
  {
    return super.latestRound();
  }
  /// @inheritdoc OffchainAggregator
  function getAnswer(uint256 _roundId)
    public
    override
    view
    checkAccess()
    returns (int256)
  {
    return super.getAnswer(_roundId);
  }
  /// @inheritdoc OffchainAggregator
  function getTimestamp(uint256 _roundId)
    public
    override
    view
    checkAccess()
    returns (uint256)
  {
    return super.getTimestamp(_roundId);
  }
  /*
   * v3 Aggregator interface
   */
  /// @inheritdoc OffchainAggregator
  function description()
    public
    override
    view
    checkAccess()
    returns (string memory)
  {
    return super.description();
  }
  /// @inheritdoc OffchainAggregator
  function getRoundData(uint80 _roundId)
    public
    override
    view
    checkAccess()
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.getRoundData(_roundId);
  }
  /// @inheritdoc OffchainAggregator
  function latestRoundData()
    public
    override
    view
    checkAccess()
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    return super.latestRoundData();
  }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
interface AccessControllerInterface {
  function hasAccess(address user, bytes calldata data) external view returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
interface AggregatorInterface {
  function latestAnswer() external view returns (int256);
  function latestTimestamp() external view returns (uint256);
  function latestRound() external view returns (uint256);
  function getAnswer(uint256 roundId) external view returns (int256);
  function getTimestamp(uint256 roundId) external view returns (uint256);
  event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
  event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "./AggregatorInterface.sol";
import "./AggregatorV3Interface.sol";
interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
{
}// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
interface AggregatorV3Interface {
  function decimals() external view returns (uint8);
  function description() external view returns (string memory);
  function version() external view returns (uint256);
  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
interface AggregatorValidatorInterface {
  function validate(
    uint256 previousRoundId,
    int256 previousAnswer,
    uint256 currentRoundId,
    int256 currentAnswer
  ) external returns (bool);
}// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
interface LinkTokenInterface {
  function allowance(address owner, address spender) external view returns (uint256 remaining);
  function approve(address spender, uint256 value) external returns (bool success);
  function balanceOf(address owner) external view returns (uint256 balance);
  function decimals() external view returns (uint8 decimalPlaces);
  function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);
  function increaseApproval(address spender, uint256 subtractedValue) external;
  function name() external view returns (string memory tokenName);
  function symbol() external view returns (string memory tokenSymbol);
  function totalSupply() external view returns (uint256 totalTokensIssued);
  function transfer(address to, uint256 value) external returns (bool success);
  function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool success);
  function transferFrom(address from, address to, uint256 value) external returns (bool success);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./AccessControllerInterface.sol";
import "./AggregatorV2V3Interface.sol";
import "./AggregatorValidatorInterface.sol";
import "./LinkTokenInterface.sol";
import "./Owned.sol";
import "./OffchainAggregatorBilling.sol";
import "./TypeAndVersionInterface.sol";
/**
  * @notice Onchain verification of reports from the offchain reporting protocol
  * @dev For details on its operation, see the offchain reporting protocol design
  * @dev doc, which refers to this contract as simply the "contract".
*/
contract OffchainAggregator is Owned, OffchainAggregatorBilling, AggregatorV2V3Interface, TypeAndVersionInterface {
  uint256 constant private maxUint32 = (1 << 32) - 1;
  // Storing these fields used on the hot path in a HotVars variable reduces the
  // retrieval of all of them to a single SLOAD. If any further fields are
  // added, make sure that storage of the struct still takes at most 32 bytes.
  struct HotVars {
    // Provides 128 bits of security against 2nd pre-image attacks, but only
    // 64 bits against collisions. This is acceptable, since a malicious owner has
    // easier way of messing up the protocol than to find hash collisions.
    bytes16 latestConfigDigest;
    uint40 latestEpochAndRound; // 32 most sig bits for epoch, 8 least sig bits for round
    // Current bound assumed on number of faulty/dishonest oracles participating
    // in the protocol, this value is referred to as f in the design
    uint8 threshold;
    // Chainlink Aggregators expose a roundId to consumers. The offchain reporting
    // protocol does not use this id anywhere. We increment it whenever a new
    // transmission is made to provide callers with contiguous ids for successive
    // reports.
    uint32 latestAggregatorRoundId;
  }
  HotVars internal s_hotVars;
  // Transmission records the median answer from the transmit transaction at
  // time timestamp
  struct Transmission {
    int192 answer; // 192 bits ought to be enough for anyone
    uint64 timestamp;
  }
  mapping(uint32 /* aggregator round ID */ => Transmission) internal s_transmissions;
  // incremented each time a new config is posted. This count is incorporated
  // into the config digest, to prevent replay attacks.
  uint32 internal s_configCount;
  uint32 internal s_latestConfigBlockNumber; // makes it easier for offchain systems
                                             // to extract config from logs.
  // Lowest answer the system is allowed to report in response to transmissions
  int192 immutable public minAnswer;
  // Highest answer the system is allowed to report in response to transmissions
  int192 immutable public maxAnswer;
  /*
   * @param _maximumGasPrice highest gas price for which transmitter will be compensated
   * @param _reasonableGasPrice transmitter will receive reward for gas prices under this value
   * @param _microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
   * @param _linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
   * @param _linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
   * @param _link address of the LINK contract
   * @param _minAnswer lowest answer the median of a report is allowed to be
   * @param _maxAnswer highest answer the median of a report is allowed to be
   * @param _billingAccessController access controller for billing admin functions
   * @param _requesterAccessController access controller for requesting new rounds
   * @param _decimals answers are stored in fixed-point format, with this many digits of precision
   * @param _description short human-readable description of observable this contract's answers pertain to
   */
  constructor(
    uint32 _maximumGasPrice,
    uint32 _reasonableGasPrice,
    uint32 _microLinkPerEth,
    uint32 _linkGweiPerObservation,
    uint32 _linkGweiPerTransmission,
    LinkTokenInterface _link,
    int192 _minAnswer,
    int192 _maxAnswer,
    AccessControllerInterface _billingAccessController,
    AccessControllerInterface _requesterAccessController,
    uint8 _decimals,
    string memory _description
  )
    OffchainAggregatorBilling(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
      _linkGweiPerObservation, _linkGweiPerTransmission, _link,
      _billingAccessController
    )
  {
    decimals = _decimals;
    s_description = _description;
    setRequesterAccessController(_requesterAccessController);
    setValidatorConfig(AggregatorValidatorInterface(0x0), 0);
    minAnswer = _minAnswer;
    maxAnswer = _maxAnswer;
  }
  /*
   * Versioning
   */
  function typeAndVersion()
    external
    override
    pure
    virtual
    returns (string memory)
  {
    return "OffchainAggregator 4.0.0";
  }
  /*
   * Config logic
   */
  /**
   * @notice triggers a new run of the offchain reporting protocol
   * @param previousConfigBlockNumber block in which the previous config was set, to simplify historic analysis
   * @param configCount ordinal number of this config setting among all config settings over the life of this contract
   * @param signers ith element is address ith oracle uses to sign a report
   * @param transmitters ith element is address ith oracle uses to transmit a report via the transmit method
   * @param threshold maximum number of faulty/dishonest oracles the protocol can tolerate while still working correctly
   * @param encodedConfigVersion version of the serialization format used for "encoded" parameter
   * @param encoded serialized data used by oracles to configure their offchain operation
   */
  event ConfigSet(
    uint32 previousConfigBlockNumber,
    uint64 configCount,
    address[] signers,
    address[] transmitters,
    uint8 threshold,
    uint64 encodedConfigVersion,
    bytes encoded
  );
  // Reverts transaction if config args are invalid
  modifier checkConfigValid (
    uint256 _numSigners, uint256 _numTransmitters, uint256 _threshold
  ) {
    require(_numSigners <= maxNumOracles, "too many signers");
    require(_threshold > 0, "threshold must be positive");
    require(
      _numSigners == _numTransmitters,
      "oracle addresses out of registration"
    );
    require(_numSigners > 3*_threshold, "faulty-oracle threshold too high");
    _;
  }
  /**
   * @notice sets offchain reporting protocol configuration incl. participating oracles
   * @param _signers addresses with which oracles sign the reports
   * @param _transmitters addresses oracles use to transmit the reports
   * @param _threshold number of faulty oracles the system can tolerate
   * @param _encodedConfigVersion version number for offchainEncoding schema
   * @param _encoded encoded off-chain oracle configuration
   */
  function setConfig(
    address[] calldata _signers,
    address[] calldata _transmitters,
    uint8 _threshold,
    uint64 _encodedConfigVersion,
    bytes calldata _encoded
  )
    external
    checkConfigValid(_signers.length, _transmitters.length, _threshold)
    onlyOwner()
  {
    while (s_signers.length != 0) { // remove any old signer/transmitter addresses
      uint lastIdx = s_signers.length - 1;
      address signer = s_signers[lastIdx];
      address transmitter = s_transmitters[lastIdx];
      payOracle(transmitter);
      delete s_oracles[signer];
      delete s_oracles[transmitter];
      s_signers.pop();
      s_transmitters.pop();
    }
    for (uint i = 0; i < _signers.length; i++) { // add new signer/transmitter addresses
      require(
        s_oracles[_signers[i]].role == Role.Unset,
        "repeated signer address"
      );
      s_oracles[_signers[i]] = Oracle(uint8(i), Role.Signer);
      require(s_payees[_transmitters[i]] != address(0), "payee must be set");
      require(
        s_oracles[_transmitters[i]].role == Role.Unset,
        "repeated transmitter address"
      );
      s_oracles[_transmitters[i]] = Oracle(uint8(i), Role.Transmitter);
      s_signers.push(_signers[i]);
      s_transmitters.push(_transmitters[i]);
    }
    s_hotVars.threshold = _threshold;
    uint32 previousConfigBlockNumber = s_latestConfigBlockNumber;
    s_latestConfigBlockNumber = uint32(block.number);
    s_configCount += 1;
    uint64 configCount = s_configCount;
    {
      s_hotVars.latestConfigDigest = configDigestFromConfigData(
        address(this),
        configCount,
        _signers,
        _transmitters,
        _threshold,
        _encodedConfigVersion,
        _encoded
      );
      s_hotVars.latestEpochAndRound = 0;
    }
    emit ConfigSet(
      previousConfigBlockNumber,
      configCount,
      _signers,
      _transmitters,
      _threshold,
      _encodedConfigVersion,
      _encoded
    );
  }
  function configDigestFromConfigData(
    address _contractAddress,
    uint64 _configCount,
    address[] calldata _signers,
    address[] calldata _transmitters,
    uint8 _threshold,
    uint64 _encodedConfigVersion,
    bytes calldata _encodedConfig
  ) internal pure returns (bytes16) {
    return bytes16(keccak256(abi.encode(_contractAddress, _configCount,
      _signers, _transmitters, _threshold, _encodedConfigVersion, _encodedConfig
    )));
  }
  /**
   * @notice information about current offchain reporting protocol configuration
   * @return configCount ordinal number of current config, out of all configs applied to this contract so far
   * @return blockNumber block at which this config was set
   * @return configDigest domain-separation tag for current config (see configDigestFromConfigData)
   */
  function latestConfigDetails()
    external
    view
    returns (
      uint32 configCount,
      uint32 blockNumber,
      bytes16 configDigest
    )
  {
    return (s_configCount, s_latestConfigBlockNumber, s_hotVars.latestConfigDigest);
  }
  /**
   * @return list of addresses permitted to transmit reports to this contract
   * @dev The list will match the order used to specify the transmitter during setConfig
   */
  function transmitters()
    external
    view
    returns(address[] memory)
  {
      return s_transmitters;
  }
  /*
   * On-chain validation logc
   */
  // Configuration for validator
  struct ValidatorConfig {
    AggregatorValidatorInterface validator;
    uint32 gasLimit;
  }
  ValidatorConfig private s_validatorConfig;
  /**
   * @notice indicates that the validator configuration has been set
   * @param previousValidator previous validator contract
   * @param previousGasLimit previous gas limit for validate calls
   * @param currentValidator current validator contract
   * @param currentGasLimit current gas limit for validate calls
   */
  event ValidatorConfigSet(
    AggregatorValidatorInterface indexed previousValidator,
    uint32 previousGasLimit,
    AggregatorValidatorInterface indexed currentValidator,
    uint32 currentGasLimit
  );
  /**
   * @notice validator configuration
   * @return validator validator contract
   * @return gasLimit gas limit for validate calls
   */
  function validatorConfig()
    external
    view
    returns (AggregatorValidatorInterface validator, uint32 gasLimit)
  {
    ValidatorConfig memory vc = s_validatorConfig;
    return (vc.validator, vc.gasLimit);
  }
  /**
   * @notice sets validator configuration
   * @dev set _newValidator to 0x0 to disable validate calls
   * @param _newValidator address of the new validator contract
   * @param _newGasLimit new gas limit for validate calls
   */
  function setValidatorConfig(AggregatorValidatorInterface _newValidator, uint32 _newGasLimit)
    public
    onlyOwner()
  {
    ValidatorConfig memory previous = s_validatorConfig;
    if (previous.validator != _newValidator || previous.gasLimit != _newGasLimit) {
      s_validatorConfig = ValidatorConfig({
        validator: _newValidator,
        gasLimit: _newGasLimit
      });
      emit ValidatorConfigSet(previous.validator, previous.gasLimit, _newValidator, _newGasLimit);
    }
  }
  function validateAnswer(
    uint32 _aggregatorRoundId,
    int256 _answer
  )
    private
  {
    ValidatorConfig memory vc = s_validatorConfig;
    if (address(vc.validator) == address(0)) {
      return;
    }
    uint32 prevAggregatorRoundId = _aggregatorRoundId - 1;
    int256 prevAggregatorRoundAnswer = s_transmissions[prevAggregatorRoundId].answer;
    require(
      callWithExactGasEvenIfTargetIsNoContract(
        vc.gasLimit,
        address(vc.validator),
        abi.encodeWithSignature(
          "validate(uint256,int256,uint256,int256)",
          uint256(prevAggregatorRoundId),
          prevAggregatorRoundAnswer,
          uint256(_aggregatorRoundId),
          _answer
        )
      ),
      "insufficient gas"
    );
  }
  uint256 private constant CALL_WITH_EXACT_GAS_CUSHION = 5_000;
  /**
   * @dev calls target address with exactly gasAmount gas and data as calldata
   * or reverts if at least gasAmount gas is not available.
   */
  function callWithExactGasEvenIfTargetIsNoContract(
    uint256 _gasAmount,
    address _target,
    bytes memory _data
  )
    private
    returns (bool sufficientGas)
  {
    // solhint-disable-next-line no-inline-assembly
    assembly {
      let g := gas()
      // Compute g -= CALL_WITH_EXACT_GAS_CUSHION and check for underflow. We
      // need the cushion since the logic following the above call to gas also
      // costs gas which we cannot account for exactly. So cushion is a
      // conservative upper bound for the cost of this logic.
      if iszero(lt(g, CALL_WITH_EXACT_GAS_CUSHION)) {
        g := sub(g, CALL_WITH_EXACT_GAS_CUSHION)
        // If g - g//64 <= _gasAmount, we don't have enough gas. (We subtract g//64
        // because of EIP-150.)
        if gt(sub(g, div(g, 64)), _gasAmount) {
          // Call and ignore success/return data. Note that we did not check
          // whether a contract actually exists at the _target address.
          pop(call(_gasAmount, _target, 0, add(_data, 0x20), mload(_data), 0, 0))
          sufficientGas := true
        }
      }
    }
  }
  /*
   * requestNewRound logic
   */
  AccessControllerInterface internal s_requesterAccessController;
  /**
   * @notice emitted when a new requester access controller contract is set
   * @param old the address prior to the current setting
   * @param current the address of the new access controller contract
   */
  event RequesterAccessControllerSet(AccessControllerInterface old, AccessControllerInterface current);
  /**
   * @notice emitted to immediately request a new round
   * @param requester the address of the requester
   * @param configDigest the latest transmission's configDigest
   * @param epoch the latest transmission's epoch
   * @param round the latest transmission's round
   */
  event RoundRequested(address indexed requester, bytes16 configDigest, uint32 epoch, uint8 round);
  /**
   * @notice address of the requester access controller contract
   * @return requester access controller address
   */
  function requesterAccessController()
    external
    view
    returns (AccessControllerInterface)
  {
    return s_requesterAccessController;
  }
  /**
   * @notice sets the requester access controller
   * @param _requesterAccessController designates the address of the new requester access controller
   */
  function setRequesterAccessController(AccessControllerInterface _requesterAccessController)
    public
    onlyOwner()
  {
    AccessControllerInterface oldController = s_requesterAccessController;
    if (_requesterAccessController != oldController) {
      s_requesterAccessController = AccessControllerInterface(_requesterAccessController);
      emit RequesterAccessControllerSet(oldController, _requesterAccessController);
    }
  }
  /**
   * @notice immediately requests a new round
   * @return the aggregatorRoundId of the next round. Note: The report for this round may have been
   * transmitted (but not yet mined) *before* requestNewRound() was even called. There is *no*
   * guarantee of causality between the request and the report at aggregatorRoundId.
   */
  function requestNewRound() external returns (uint80) {
    require(msg.sender == owner || s_requesterAccessController.hasAccess(msg.sender, msg.data),
      "Only owner&requester can call");
    HotVars memory hotVars = s_hotVars;
    emit RoundRequested(
      msg.sender,
      hotVars.latestConfigDigest,
      uint32(s_hotVars.latestEpochAndRound >> 8),
      uint8(s_hotVars.latestEpochAndRound)
    );
    return hotVars.latestAggregatorRoundId + 1;
  }
  /*
   * Transmission logic
   */
  /**
   * @notice indicates that a new report was transmitted
   * @param aggregatorRoundId the round to which this report was assigned
   * @param answer median of the observations attached this report
   * @param transmitter address from which the report was transmitted
   * @param observations observations transmitted with this report
   * @param rawReportContext signature-replay-prevention domain-separation tag
   */
  event NewTransmission(
    uint32 indexed aggregatorRoundId,
    int192 answer,
    address transmitter,
    int192[] observations,
    bytes observers,
    bytes32 rawReportContext
  );
  // decodeReport is used to check that the solidity and go code are using the
  // same format. See TestOffchainAggregator.testDecodeReport and TestReportParsing
  function decodeReport(bytes memory _report)
    internal
    pure
    returns (
      bytes32 rawReportContext,
      bytes32 rawObservers,
      int192[] memory observations
    )
  {
    (rawReportContext, rawObservers, observations) = abi.decode(_report,
      (bytes32, bytes32, int192[]));
  }
  // Used to relieve stack pressure in transmit
  struct ReportData {
    HotVars hotVars; // Only read from storage once
    bytes observers; // ith element is the index of the ith observer
    int192[] observations; // ith element is the ith observation
    bytes vs; // jth element is the v component of the jth signature
    bytes32 rawReportContext;
  }
  /*
   * @notice details about the most recent report
   * @return configDigest domain separation tag for the latest report
   * @return epoch epoch in which the latest report was generated
   * @return round OCR round in which the latest report was generated
   * @return latestAnswer median value from latest report
   * @return latestTimestamp when the latest report was transmitted
   */
  function latestTransmissionDetails()
    external
    view
    returns (
      bytes16 configDigest,
      uint32 epoch,
      uint8 round,
      int192 latestAnswer,
      uint64 latestTimestamp
    )
  {
    require(msg.sender == tx.origin, "Only callable by EOA");
    return (
      s_hotVars.latestConfigDigest,
      uint32(s_hotVars.latestEpochAndRound >> 8),
      uint8(s_hotVars.latestEpochAndRound),
      s_transmissions[s_hotVars.latestAggregatorRoundId].answer,
      s_transmissions[s_hotVars.latestAggregatorRoundId].timestamp
    );
  }
  // The constant-length components of the msg.data sent to transmit.
  // See the "If we wanted to call sam" example on for example reasoning
  // https://solidity.readthedocs.io/en/v0.7.2/abi-spec.html
  uint16 private constant TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT =
    4 + // function selector
    32 + // word containing start location of abiencoded _report value
    32 + // word containing location start of abiencoded  _rs value
    32 + // word containing start location of abiencoded _ss value
    32 + // _rawVs value
    32 + // word containing length of _report
    32 + // word containing length _rs
    32 + // word containing length of _ss
    0; // placeholder
  function expectedMsgDataLength(
    bytes calldata _report, bytes32[] calldata _rs, bytes32[] calldata _ss
  ) private pure returns (uint256 length)
  {
    // calldata will never be big enough to make this overflow
    return uint256(TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT) +
      _report.length + // one byte pure entry in _report
      _rs.length * 32 + // 32 bytes per entry in _rs
      _ss.length * 32 + // 32 bytes per entry in _ss
      0; // placeholder
  }
  /**
   * @notice transmit is called to post a new report to the contract
   * @param _report serialized report, which the signatures are signing. See parsing code below for format. The ith element of the observers component must be the index in s_signers of the address for the ith signature
   * @param _rs ith element is the R components of the ith signature on report. Must have at most maxNumOracles entries
   * @param _ss ith element is the S components of the ith signature on report. Must have at most maxNumOracles entries
   * @param _rawVs ith element is the the V component of the ith signature
   */
  function transmit(
    // NOTE: If these parameters are changed, expectedMsgDataLength and/or
    // TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT need to be changed accordingly
    bytes calldata _report,
    bytes32[] calldata _rs, bytes32[] calldata _ss, bytes32 _rawVs // signatures
  )
    external
  {
    uint256 initialGas = gasleft(); // This line must come first
    // Make sure the transmit message-length matches the inputs. Otherwise, the
    // transmitter could append an arbitrarily long (up to gas-block limit)
    // string of 0 bytes, which we would reimburse at a rate of 16 gas/byte, but
    // which would only cost the transmitter 4 gas/byte. (Appendix G of the
    // yellow paper, p. 25, for G_txdatazero and EIP 2028 for G_txdatanonzero.)
    // This could amount to reimbursement profit of 36 million gas, given a 3MB
    // zero tail.
    require(msg.data.length == expectedMsgDataLength(_report, _rs, _ss),
      "transmit message too long");
    ReportData memory r; // Relieves stack pressure
    {
      r.hotVars = s_hotVars; // cache read from storage
      bytes32 rawObservers;
      (r.rawReportContext, rawObservers, r.observations) = abi.decode(
        _report, (bytes32, bytes32, int192[])
      );
      // rawReportContext consists of:
      // 11-byte zero padding
      // 16-byte configDigest
      // 4-byte epoch
      // 1-byte round
      bytes16 configDigest = bytes16(r.rawReportContext << 88);
      require(
        r.hotVars.latestConfigDigest == configDigest,
        "configDigest mismatch"
      );
      uint40 epochAndRound = uint40(uint256(r.rawReportContext));
      // direct numerical comparison works here, because
      //
      //   ((e,r) <= (e',r')) implies (epochAndRound <= epochAndRound')
      //
      // because alphabetic ordering implies e <= e', and if e = e', then r<=r',
      // so e*256+r <= e'*256+r', because r, r' < 256
      require(r.hotVars.latestEpochAndRound < epochAndRound, "stale report");
      require(_rs.length > r.hotVars.threshold, "not enough signatures");
      require(_rs.length <= maxNumOracles, "too many signatures");
      require(_ss.length == _rs.length, "signatures out of registration");
      require(r.observations.length <= maxNumOracles,
              "num observations out of bounds");
      require(r.observations.length > 2 * r.hotVars.threshold,
              "too few values to trust median");
      // Copy signature parities in bytes32 _rawVs to bytes r.v
      r.vs = new bytes(_rs.length);
      for (uint8 i = 0; i < _rs.length; i++) {
        r.vs[i] = _rawVs[i];
      }
      // Copy observer identities in bytes32 rawObservers to bytes r.observers
      r.observers = new bytes(r.observations.length);
      bool[maxNumOracles] memory seen;
      for (uint8 i = 0; i < r.observations.length; i++) {
        uint8 observerIdx = uint8(rawObservers[i]);
        require(!seen[observerIdx], "observer index repeated");
        seen[observerIdx] = true;
        r.observers[i] = rawObservers[i];
      }
      Oracle memory transmitter = s_oracles[msg.sender];
      require( // Check that sender is authorized to report
        transmitter.role == Role.Transmitter &&
        msg.sender == s_transmitters[transmitter.index],
        "unauthorized transmitter"
      );
      // record epochAndRound here, so that we don't have to carry the local
      // variable in transmit. The change is reverted if something fails later.
      r.hotVars.latestEpochAndRound = epochAndRound;
    }
    { // Verify signatures attached to report
      bytes32 h = keccak256(_report);
      bool[maxNumOracles] memory signed;
      Oracle memory o;
      for (uint i = 0; i < _rs.length; i++) {
        address signer = ecrecover(h, uint8(r.vs[i])+27, _rs[i], _ss[i]);
        o = s_oracles[signer];
        require(o.role == Role.Signer, "address not authorized to sign");
        require(!signed[o.index], "non-unique signature");
        signed[o.index] = true;
      }
    }
    { // Check the report contents, and record the result
      for (uint i = 0; i < r.observations.length - 1; i++) {
        bool inOrder = r.observations[i] <= r.observations[i+1];
        require(inOrder, "observations not sorted");
      }
      int192 median = r.observations[r.observations.length/2];
      require(minAnswer <= median && median <= maxAnswer, "median is out of min-max range");
      r.hotVars.latestAggregatorRoundId++;
      s_transmissions[r.hotVars.latestAggregatorRoundId] =
        Transmission(median, uint64(block.timestamp));
      emit NewTransmission(
        r.hotVars.latestAggregatorRoundId,
        median,
        msg.sender,
        r.observations,
        r.observers,
        r.rawReportContext
      );
      // Emit these for backwards compatability with offchain consumers
      // that only support legacy events
      emit NewRound(
        r.hotVars.latestAggregatorRoundId,
        address(0x0), // use zero address since we don't have anybody "starting" the round here
        block.timestamp
      );
      emit AnswerUpdated(
        median,
        r.hotVars.latestAggregatorRoundId,
        block.timestamp
      );
      validateAnswer(r.hotVars.latestAggregatorRoundId, median);
    }
    s_hotVars = r.hotVars;
    assert(initialGas < maxUint32);
    reimburseAndRewardOracles(uint32(initialGas), r.observers);
  }
  /*
   * v2 Aggregator interface
   */
  /**
   * @notice median from the most recent report
   */
  function latestAnswer()
    public
    override
    view
    virtual
    returns (int256)
  {
    return s_transmissions[s_hotVars.latestAggregatorRoundId].answer;
  }
  /**
   * @notice timestamp of block in which last report was transmitted
   */
  function latestTimestamp()
    public
    override
    view
    virtual
    returns (uint256)
  {
    return s_transmissions[s_hotVars.latestAggregatorRoundId].timestamp;
  }
  /**
   * @notice Aggregator round (NOT OCR round) in which last report was transmitted
   */
  function latestRound()
    public
    override
    view
    virtual
    returns (uint256)
  {
    return s_hotVars.latestAggregatorRoundId;
  }
  /**
   * @notice median of report from given aggregator round (NOT OCR round)
   * @param _roundId the aggregator round of the target report
   */
  function getAnswer(uint256 _roundId)
    public
    override
    view
    virtual
    returns (int256)
  {
    if (_roundId > 0xFFFFFFFF) { return 0; }
    return s_transmissions[uint32(_roundId)].answer;
  }
  /**
   * @notice timestamp of block in which report from given aggregator round was transmitted
   * @param _roundId aggregator round (NOT OCR round) of target report
   */
  function getTimestamp(uint256 _roundId)
    public
    override
    view
    virtual
    returns (uint256)
  {
    if (_roundId > 0xFFFFFFFF) { return 0; }
    return s_transmissions[uint32(_roundId)].timestamp;
  }
  /*
   * v3 Aggregator interface
   */
  string constant private V3_NO_DATA_ERROR = "No data present";
  /**
   * @return answers are stored in fixed-point format, with this many digits of precision
   */
  uint8 immutable public override decimals;
  /**
   * @notice aggregator contract version
   */
  uint256 constant public override version = 4;
  string internal s_description;
  /**
   * @notice human-readable description of observable this contract is reporting on
   */
  function description()
    public
    override
    view
    virtual
    returns (string memory)
  {
    return s_description;
  }
  /**
   * @notice details for the given aggregator round
   * @param _roundId target aggregator round (NOT OCR round). Must fit in uint32
   * @return roundId _roundId
   * @return answer median of report from given _roundId
   * @return startedAt timestamp of block in which report from given _roundId was transmitted
   * @return updatedAt timestamp of block in which report from given _roundId was transmitted
   * @return answeredInRound _roundId
   */
  function getRoundData(uint80 _roundId)
    public
    override
    view
    virtual
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    require(_roundId <= 0xFFFFFFFF, V3_NO_DATA_ERROR);
    Transmission memory transmission = s_transmissions[uint32(_roundId)];
    return (
      _roundId,
      transmission.answer,
      transmission.timestamp,
      transmission.timestamp,
      _roundId
    );
  }
  /**
   * @notice aggregator details for the most recently transmitted report
   * @return roundId aggregator round of latest report (NOT OCR round)
   * @return answer median of latest report
   * @return startedAt timestamp of block containing latest report
   * @return updatedAt timestamp of block containing latest report
   * @return answeredInRound aggregator round of latest report
   */
  function latestRoundData()
    public
    override
    view
    virtual
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    )
  {
    roundId = s_hotVars.latestAggregatorRoundId;
    // Skipped for compatability with existing FluxAggregator in which latestRoundData never reverts.
    // require(roundId != 0, V3_NO_DATA_ERROR);
    Transmission memory transmission = s_transmissions[uint32(roundId)];
    return (
      roundId,
      transmission.answer,
      transmission.timestamp,
      transmission.timestamp,
      roundId
    );
  }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./AccessControllerInterface.sol";
import "./LinkTokenInterface.sol";
import "./Owned.sol";
/**
 * @notice tracks administration of oracle-reward and gas-reimbursement parameters.
 * @dev
 * If you read or change this, be sure to read or adjust the comments. They
 * track the units of the values under consideration, and are crucial to
 * the readability of the operations it specifies.
 * @notice
 * Trust Model:
 * Nothing in this contract prevents a billing admin from setting insane
 * values for the billing parameters in setBilling. Oracles
 * participating in this contract should regularly check that the
 * parameters make sense. Similarly, the outstanding obligations of this
 * contract to the oracles can exceed the funds held by the contract.
 * Oracles participating in this contract should regularly check that it
 * holds sufficient funds and stop interacting with it if funding runs
 * out.
 * This still leaves oracles with some risk due to TOCTOU issues.
 * However, since the sums involved are pretty small (Ethereum
 * transactions aren't that expensive in the end) and an oracle would
 * likely stop participating in a contract it repeatedly lost money on,
 * this risk is deemed acceptable. Oracles should also regularly
 * withdraw any funds in the contract to prevent issues where the
 * contract becomes underfunded at a later time, and different oracles
 * are competing for the left-over funds.
 * Finally, note that any change to the set of oracles or to the billing
 * parameters will trigger payout of all oracles first (using the old
 * parameters), a billing admin cannot take away funds that are already
 * marked for payment.
*/
contract OffchainAggregatorBilling is Owned {
  // Maximum number of oracles the offchain reporting protocol is designed for
  uint256 constant internal maxNumOracles = 31;
  // Parameters for oracle payments
  struct Billing {
    // Highest compensated gas price, in ETH-gwei uints
    uint32 maximumGasPrice;
    // If gas price is less (in ETH-gwei units), transmitter gets half the savings
    uint32 reasonableGasPrice;
    // Pay transmitter back this much LINK per unit eth spent on gas
    // (1e-6LINK/ETH units)
    uint32 microLinkPerEth;
    // Fixed LINK reward for each observer, in LINK-gwei units
    uint32 linkGweiPerObservation;
    // Fixed reward for transmitter, in linkGweiPerObservation units
    uint32 linkGweiPerTransmission;
  }
  Billing internal s_billing;
  // We assume that the token contract is correct. This contract is not written
  // to handle misbehaving ERC20 tokens!
  LinkTokenInterface internal s_linkToken;
  AccessControllerInterface internal s_billingAccessController;
  // ith element is number of observation rewards due to ith process, plus one.
  // This is expected to saturate after an oracle has submitted 65,535
  // observations, or about 65535/(3*24*20) = 45 days, given a transmission
  // every 3 minutes.
  //
  // This is always one greater than the actual value, so that when the value is
  // reset to zero, we don't end up with a zero value in storage (which would
  // result in a higher gas cost, the next time the value is incremented.)
  // Calculations using this variable need to take that offset into account.
  uint16[maxNumOracles] internal s_oracleObservationsCounts;
  // Addresses at which oracles want to receive payments, by transmitter address
  mapping (address /* transmitter */ => address /* payment address */)
    internal
    s_payees;
  // Payee addresses which must be approved by the owner
  mapping (address /* transmitter */ => address /* payment address */)
    internal
    s_proposedPayees;
  // LINK-wei-denominated reimbursements for gas used by transmitters.
  //
  // This is always one greater than the actual value, so that when the value is
  // reset to zero, we don't end up with a zero value in storage (which would
  // result in a higher gas cost, the next time the value is incremented.)
  // Calculations using this variable need to take that offset into account.
  //
  // Argument for overflow safety:
  // We have the following maximum intermediate values:
  // - 2**40 additions to this variable (epochAndRound is a uint40)
  // - 2**32 gas price in ethgwei/gas
  // - 1e9 ethwei/ethgwei
  // - 2**32 gas since the block gas limit is at ~20 million
  // - 2**32 (microlink/eth)
  // And we have 2**40 * 2**32 * 1e9 * 2**32 * 2**32 < 2**166
  // (we also divide in some places, but that only makes the value smaller)
  // We can thus safely use uint256 intermediate values for the computation
  // updating this variable.
  uint256[maxNumOracles] internal s_gasReimbursementsLinkWei;
  // Used for s_oracles[a].role, where a is an address, to track the purpose
  // of the address, or to indicate that the address is unset.
  enum Role {
    // No oracle role has been set for address a
    Unset,
    // Signing address for the s_oracles[a].index'th oracle. I.e., report
    // signatures from this oracle should ecrecover back to address a.
    Signer,
    // Transmission address for the s_oracles[a].index'th oracle. I.e., if a
    // report is received by OffchainAggregator.transmit in which msg.sender is
    // a, it is attributed to the s_oracles[a].index'th oracle.
    Transmitter
  }
  struct Oracle {
    uint8 index; // Index of oracle in s_signers/s_transmitters
    Role role;   // Role of the address which mapped to this struct
  }
  mapping (address /* signer OR transmitter address */ => Oracle)
    internal s_oracles;
  // s_signers contains the signing address of each oracle
  address[] internal s_signers;
  // s_transmitters contains the transmission address of each oracle,
  // i.e. the address the oracle actually sends transactions to the contract from
  address[] internal s_transmitters;
  uint256 constant private  maxUint16 = (1 << 16) - 1;
  uint256 constant internal maxUint128 = (1 << 128) - 1;
  constructor(
    uint32 _maximumGasPrice,
    uint32 _reasonableGasPrice,
    uint32 _microLinkPerEth,
    uint32 _linkGweiPerObservation,
    uint32 _linkGweiPerTransmission,
    LinkTokenInterface _link,
    AccessControllerInterface _billingAccessController
  )
  {
    setBillingInternal(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
      _linkGweiPerObservation, _linkGweiPerTransmission);
    s_linkToken = _link;
    emit LinkTokenSet(LinkTokenInterface(address(0)), _link);
    setBillingAccessControllerInternal(_billingAccessController);
    uint16[maxNumOracles] memory counts; // See s_oracleObservationsCounts docstring
    uint256[maxNumOracles] memory gas; // see s_gasReimbursementsLinkWei docstring
    for (uint8 i = 0; i < maxNumOracles; i++) {
      counts[i] = 1;
      gas[i] = 1;
    }
    s_oracleObservationsCounts = counts;
    s_gasReimbursementsLinkWei = gas;
  }
  /*
   * @notice emitted when the LINK token contract is set
   * @param _oldLinkToken the address of the old LINK token contract
   * @param _newLinkToken the address of the new LINK token contract
   */
  event LinkTokenSet(
    LinkTokenInterface indexed _oldLinkToken,
    LinkTokenInterface indexed _newLinkToken
  );
  /*
   * @notice sets the LINK token contract used for paying oracles
   * @param _linkToken the address of the LINK token contract
   * @param _recipient remaining funds from the previous token contract are transfered
   * here
   * @dev this function will return early (without an error) without changing any state
   * if _linkToken equals getLinkToken().
   * @dev this will trigger a payout so that a malicious owner cannot take from oracles
   * what is already owed to them.
   * @dev we assume that the token contract is correct. This contract is not written
   * to handle misbehaving ERC20 tokens!
   */
  function setLinkToken(
    LinkTokenInterface _linkToken,
    address _recipient
  ) external
    onlyOwner()
  {
    LinkTokenInterface oldLinkToken = s_linkToken;
    if (_linkToken == oldLinkToken) {
      // No change, nothing to be done
      return;
    }
    // call balanceOf as a sanity check on whether we're talking to a token
    // contract
    _linkToken.balanceOf(address(this));
    // we break CEI here, but that's okay because we're dealing with a correct
    // token contract (by assumption).
    payOracles();
    uint256 remainingBalance = oldLinkToken.balanceOf(address(this));
    require(oldLinkToken.transfer(_recipient, remainingBalance), "transfer remaining funds failed");
    s_linkToken = _linkToken;
    emit LinkTokenSet(oldLinkToken, _linkToken);
  }
  /*
   * @notice gets the LINK token contract used for paying oracles
   * @return linkToken the address of the LINK token contract
   */
  function getLinkToken()
    external
    view
    returns(LinkTokenInterface linkToken)
  {
    return s_linkToken;
  }
  /**
   * @notice emitted when billing parameters are set
   * @param maximumGasPrice highest gas price for which transmitter will be compensated
   * @param reasonableGasPrice transmitter will receive reward for gas prices under this value
   * @param microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
   * @param linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
   * @param linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
   */
  event BillingSet(
    uint32 maximumGasPrice,
    uint32 reasonableGasPrice,
    uint32 microLinkPerEth,
    uint32 linkGweiPerObservation,
    uint32 linkGweiPerTransmission
  );
  function setBillingInternal(
    uint32 _maximumGasPrice,
    uint32 _reasonableGasPrice,
    uint32 _microLinkPerEth,
    uint32 _linkGweiPerObservation,
    uint32 _linkGweiPerTransmission
  )
    internal
  {
    s_billing = Billing(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
      _linkGweiPerObservation, _linkGweiPerTransmission);
    emit BillingSet(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
      _linkGweiPerObservation, _linkGweiPerTransmission);
  }
  /**
   * @notice sets billing parameters
   * @param _maximumGasPrice highest gas price for which transmitter will be compensated
   * @param _reasonableGasPrice transmitter will receive reward for gas prices under this value
   * @param _microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
   * @param _linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
   * @param _linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
   * @dev access control provided by billingAccessController
   */
  function setBilling(
    uint32 _maximumGasPrice,
    uint32 _reasonableGasPrice,
    uint32 _microLinkPerEth,
    uint32 _linkGweiPerObservation,
    uint32 _linkGweiPerTransmission
  )
    external
  {
    AccessControllerInterface access = s_billingAccessController;
    require(msg.sender == owner || access.hasAccess(msg.sender, msg.data),
      "Only owner&billingAdmin can call");
    payOracles();
    setBillingInternal(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
      _linkGweiPerObservation, _linkGweiPerTransmission);
  }
  /**
   * @notice gets billing parameters
   * @param maximumGasPrice highest gas price for which transmitter will be compensated
   * @param reasonableGasPrice transmitter will receive reward for gas prices under this value
   * @param microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
   * @param linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
   * @param linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
   */
  function getBilling()
    external
    view
    returns (
      uint32 maximumGasPrice,
      uint32 reasonableGasPrice,
      uint32 microLinkPerEth,
      uint32 linkGweiPerObservation,
      uint32 linkGweiPerTransmission
    )
  {
    Billing memory billing = s_billing;
    return (
      billing.maximumGasPrice,
      billing.reasonableGasPrice,
      billing.microLinkPerEth,
      billing.linkGweiPerObservation,
      billing.linkGweiPerTransmission
    );
  }
  /**
   * @notice emitted when a new access-control contract is set
   * @param old the address prior to the current setting
   * @param current the address of the new access-control contract
   */
  event BillingAccessControllerSet(AccessControllerInterface old, AccessControllerInterface current);
  function setBillingAccessControllerInternal(AccessControllerInterface _billingAccessController)
    internal
  {
    AccessControllerInterface oldController = s_billingAccessController;
    if (_billingAccessController != oldController) {
      s_billingAccessController = _billingAccessController;
      emit BillingAccessControllerSet(
        oldController,
        _billingAccessController
      );
    }
  }
  /**
   * @notice sets billingAccessController
   * @param _billingAccessController new billingAccessController contract address
   * @dev only owner can call this
   */
  function setBillingAccessController(AccessControllerInterface _billingAccessController)
    external
    onlyOwner
  {
    setBillingAccessControllerInternal(_billingAccessController);
  }
  /**
   * @notice gets billingAccessController
   * @return address of billingAccessController contract
   */
  function billingAccessController()
    external
    view
    returns (AccessControllerInterface)
  {
    return s_billingAccessController;
  }
  /**
   * @notice withdraws an oracle's payment from the contract
   * @param _transmitter the transmitter address of the oracle
   * @dev must be called by oracle's payee address
   */
  function withdrawPayment(address _transmitter)
    external
  {
    require(msg.sender == s_payees[_transmitter], "Only payee can withdraw");
    payOracle(_transmitter);
  }
  /**
   * @notice query an oracle's payment amount
   * @param _transmitter the transmitter address of the oracle
   */
  function owedPayment(address _transmitter)
    public
    view
    returns (uint256)
  {
    Oracle memory oracle = s_oracles[_transmitter];
    if (oracle.role == Role.Unset) { return 0; }
    Billing memory billing = s_billing;
    uint256 linkWeiAmount =
      uint256(s_oracleObservationsCounts[oracle.index] - 1) *
      uint256(billing.linkGweiPerObservation) *
      (1 gwei);
    linkWeiAmount += s_gasReimbursementsLinkWei[oracle.index] - 1;
    return linkWeiAmount;
  }
  /**
   * @notice emitted when an oracle has been paid LINK
   * @param transmitter address from which the oracle sends reports to the transmit method
   * @param payee address to which the payment is sent
   * @param amount amount of LINK sent
   * @param linkToken address of the LINK token contract
   */
  event OraclePaid(
    address indexed transmitter,
    address indexed payee,
    uint256 amount,
    LinkTokenInterface indexed linkToken
  );
  // payOracle pays out _transmitter's balance to the corresponding payee, and zeros it out
  function payOracle(address _transmitter)
    internal
  {
    Oracle memory oracle = s_oracles[_transmitter];
    uint256 linkWeiAmount = owedPayment(_transmitter);
    if (linkWeiAmount > 0) {
      address payee = s_payees[_transmitter];
      // Poses no re-entrancy issues, because LINK.transfer does not yield
      // control flow.
      require(s_linkToken.transfer(payee, linkWeiAmount), "insufficient funds");
      s_oracleObservationsCounts[oracle.index] = 1; // "zero" the counts. see var's docstring
      s_gasReimbursementsLinkWei[oracle.index] = 1; // "zero" the counts. see var's docstring
      emit OraclePaid(_transmitter, payee, linkWeiAmount, s_linkToken);
    }
  }
  // payOracles pays out all transmitters, and zeros out their balances.
  //
  // It's much more gas-efficient to do this as a single operation, to avoid
  // hitting storage too much.
  function payOracles()
    internal
  {
    Billing memory billing = s_billing;
    LinkTokenInterface linkToken = s_linkToken;
    uint16[maxNumOracles] memory observationsCounts = s_oracleObservationsCounts;
    uint256[maxNumOracles] memory gasReimbursementsLinkWei =
      s_gasReimbursementsLinkWei;
    address[] memory transmitters = s_transmitters;
    for (uint transmitteridx = 0; transmitteridx < transmitters.length; transmitteridx++) {
      uint256 reimbursementAmountLinkWei = gasReimbursementsLinkWei[transmitteridx] - 1;
      uint256 obsCount = observationsCounts[transmitteridx] - 1;
      uint256 linkWeiAmount =
        obsCount * uint256(billing.linkGweiPerObservation) * (1 gwei) + reimbursementAmountLinkWei;
      if (linkWeiAmount > 0) {
          address payee = s_payees[transmitters[transmitteridx]];
          // Poses no re-entrancy issues, because LINK.transfer does not yield
          // control flow.
          require(linkToken.transfer(payee, linkWeiAmount), "insufficient funds");
          observationsCounts[transmitteridx] = 1;       // "zero" the counts.
          gasReimbursementsLinkWei[transmitteridx] = 1; // "zero" the counts.
          emit OraclePaid(transmitters[transmitteridx], payee, linkWeiAmount, linkToken);
        }
    }
    // "Zero" the accounting storage variables
    s_oracleObservationsCounts = observationsCounts;
    s_gasReimbursementsLinkWei = gasReimbursementsLinkWei;
  }
  function oracleRewards(
    bytes memory observers,
    uint16[maxNumOracles] memory observations
  )
    internal
    pure
    returns (uint16[maxNumOracles] memory)
  {
    // reward each observer-participant with the observer reward
    for (uint obsIdx = 0; obsIdx < observers.length; obsIdx++) {
      uint8 observer = uint8(observers[obsIdx]);
      observations[observer] = saturatingAddUint16(observations[observer], 1);
    }
    return observations;
  }
  // This value needs to change if maxNumOracles is increased, or the accounting
  // calculations at the bottom of reimburseAndRewardOracles change.
  //
  // To recalculate it, run the profiler as described in
  // ../../profile/README.md, and add up the gas-usage values reported for the
  // lines in reimburseAndRewardOracles following the "gasLeft = gasleft()"
  // line. E.g., you will see output like this:
  //
  //      7        uint256 gasLeft = gasleft();
  //     29        uint256 gasCostEthWei = transmitterGasCostEthWei(
  //      9          uint256(initialGas),
  //      3          gasPrice,
  //      3          callDataGasCost,
  //      3          gasLeft
  //      .
  //      .
  //      .
  //     59        uint256 gasCostLinkWei = (gasCostEthWei * billing.microLinkPerEth)/ 1e6;
  //      .
  //      .
  //      .
  //   5047        s_gasReimbursementsLinkWei[txOracle.index] =
  //    856          s_gasReimbursementsLinkWei[txOracle.index] + gasCostLinkWei +
  //     26          uint256(billing.linkGweiPerTransmission) * (1 gwei);
  //
  // If those were the only lines to be accounted for, you would add up
  // 29+9+3+3+3+59+5047+856+26=6035.
  uint256 internal constant accountingGasCost = 6035;
  // Uncomment the following declaration to compute the remaining gas cost after
  // above gasleft(). (This must exist in a base class to OffchainAggregator, so
  // it can't go in TestOffchainAggregator.)
  //
  // uint256 public gasUsedInAccounting;
  // Gas price at which the transmitter should be reimbursed, in ETH-gwei/gas
  function impliedGasPrice(
    uint256 txGasPrice,         // ETH-gwei/gas units
    uint256 reasonableGasPrice, // ETH-gwei/gas units
    uint256 maximumGasPrice     // ETH-gwei/gas units
  )
    internal
    pure
    returns (uint256)
  {
    // Reward the transmitter for choosing an efficient gas price: if they manage
    // to come in lower than considered reasonable, give them half the savings.
    //
    // The following calculations are all in units of gwei/gas, i.e. 1e-9ETH/gas
    uint256 gasPrice = txGasPrice;
    if (txGasPrice < reasonableGasPrice) {
      // Give transmitter half the savings for coming in under the reasonable gas price
      gasPrice += (reasonableGasPrice - txGasPrice) / 2;
    }
    // Don't reimburse a gas price higher than maximumGasPrice
    return min(gasPrice, maximumGasPrice);
  }
  // gas reimbursement due the transmitter, in ETH-wei
  //
  // If this function is changed, accountingGasCost needs to change, too. See
  // its docstring
  function transmitterGasCostEthWei(
    uint256 initialGas,
    uint256 gasPrice, // ETH-gwei/gas units
    uint256 callDataCost, // gas units
    uint256 gasLeft
  )
    internal
    pure
    returns (uint128 gasCostEthWei)
  {
    require(initialGas >= gasLeft, "gasLeft cannot exceed initialGas");
    uint256 gasUsed = // gas units
      initialGas - gasLeft + // observed gas usage
      callDataCost + accountingGasCost; // estimated gas usage
    // gasUsed is in gas units, gasPrice is in ETH-gwei/gas units; convert to ETH-wei
    uint256 fullGasCostEthWei = gasUsed * gasPrice * (1 gwei);
    assert(fullGasCostEthWei < maxUint128); // the entire ETH supply fits in a uint128...
    return uint128(fullGasCostEthWei);
  }
  /**
   * @notice withdraw any available funds left in the contract, up to _amount, after accounting for the funds due to participants in past reports
   * @param _recipient address to send funds to
   * @param _amount maximum amount to withdraw, denominated in LINK-wei.
   * @dev access control provided by billingAccessController
   */
  function withdrawFunds(address _recipient, uint256 _amount)
    external
  {
    require(msg.sender == owner || s_billingAccessController.hasAccess(msg.sender, msg.data),
      "Only owner&billingAdmin can call");
    uint256 linkDue = totalLINKDue();
    uint256 linkBalance = s_linkToken.balanceOf(address(this));
    require(linkBalance >= linkDue, "insufficient balance");
    require(s_linkToken.transfer(_recipient, min(linkBalance - linkDue, _amount)), "insufficient funds");
  }
  // Total LINK due to participants in past reports.
  function totalLINKDue()
    internal
    view
    returns (uint256 linkDue)
  {
    // Argument for overflow safety: We do all computations in
    // uint256s. The inputs to linkDue are:
    // - the <= 31 observation rewards each of which has less than
    //   64 bits (32 bits for billing.linkGweiPerObservation, 32 bits
    //   for wei/gwei conversion). Hence 69 bits are sufficient for this part.
    // - the <= 31 gas reimbursements, each of which consists of at most 166
    //   bits (see s_gasReimbursementsLinkWei docstring). Hence 171 bits are
    //   sufficient for this part
    // In total, 172 bits are enough.
    uint16[maxNumOracles] memory observationCounts = s_oracleObservationsCounts;
    for (uint i = 0; i < maxNumOracles; i++) {
      linkDue += observationCounts[i] - 1; // Stored value is one greater than actual value
    }
    Billing memory billing = s_billing;
    // Convert linkGweiPerObservation to uint256, or this overflows!
    linkDue *= uint256(billing.linkGweiPerObservation) * (1 gwei);
    address[] memory transmitters = s_transmitters;
    uint256[maxNumOracles] memory gasReimbursementsLinkWei =
      s_gasReimbursementsLinkWei;
    for (uint i = 0; i < transmitters.length; i++) {
      linkDue += uint256(gasReimbursementsLinkWei[i]-1); // Stored value is one greater than actual value
    }
  }
  /**
   * @notice allows oracles to check that sufficient LINK balance is available
   * @return availableBalance LINK available on this contract, after accounting for outstanding obligations. can become negative
   */
  function linkAvailableForPayment()
    external
    view
    returns (int256 availableBalance)
  {
    // there are at most one billion LINK, so this cast is safe
    int256 balance = int256(s_linkToken.balanceOf(address(this)));
    // according to the argument in the definition of totalLINKDue,
    // totalLINKDue is never greater than 2**172, so this cast is safe
    int256 due = int256(totalLINKDue());
    // safe from overflow according to above sizes
    return int256(balance) - int256(due);
  }
  /**
   * @notice number of observations oracle is due to be reimbursed for
   * @param _signerOrTransmitter address used by oracle for signing or transmitting reports
   */
  function oracleObservationCount(address _signerOrTransmitter)
    external
    view
    returns (uint16)
  {
    Oracle memory oracle = s_oracles[_signerOrTransmitter];
    if (oracle.role == Role.Unset) { return 0; }
    return s_oracleObservationsCounts[oracle.index] - 1;
  }
  function reimburseAndRewardOracles(
    uint32 initialGas,
    bytes memory observers
  )
    internal
  {
    Oracle memory txOracle = s_oracles[msg.sender];
    Billing memory billing = s_billing;
    // Reward oracles for providing observations. Oracles are not rewarded
    // for providing signatures, because signing is essentially free.
    s_oracleObservationsCounts =
      oracleRewards(observers, s_oracleObservationsCounts);
    // Reimburse transmitter of the report for gas usage
    require(txOracle.role == Role.Transmitter,
      "sent by undesignated transmitter"
    );
    uint256 gasPrice = impliedGasPrice(
      tx.gasprice / (1 gwei), // convert to ETH-gwei units
      billing.reasonableGasPrice,
      billing.maximumGasPrice
    );
    // The following is only an upper bound, as it ignores the cheaper cost for
    // 0 bytes. Safe from overflow, because calldata just isn't that long.
    uint256 callDataGasCost = 16 * msg.data.length;
    // If any changes are made to subsequent calculations, accountingGasCost
    // needs to change, too.
    uint256 gasLeft = gasleft();
    uint256 gasCostEthWei = transmitterGasCostEthWei(
      uint256(initialGas),
      gasPrice,
      callDataGasCost,
      gasLeft
    );
    // microLinkPerEth is 1e-6LINK/ETH units, gasCostEthWei is 1e-18ETH units
    // (ETH-wei), product is 1e-24LINK-wei units, dividing by 1e6 gives
    // 1e-18LINK units, i.e. LINK-wei units
    // Safe from over/underflow, since all components are non-negative,
    // gasCostEthWei will always fit into uint128 and microLinkPerEth is a
    // uint32 (128+32 < 256!).
    uint256 gasCostLinkWei = (gasCostEthWei * billing.microLinkPerEth)/ 1e6;
    // Safe from overflow, because gasCostLinkWei < 2**160 and
    // billing.linkGweiPerTransmission * (1 gwei) < 2**64 and we increment
    // s_gasReimbursementsLinkWei[txOracle.index] at most 2**40 times.
    s_gasReimbursementsLinkWei[txOracle.index] =
      s_gasReimbursementsLinkWei[txOracle.index] + gasCostLinkWei +
      uint256(billing.linkGweiPerTransmission) * (1 gwei); // convert from linkGwei to linkWei
    // Uncomment next line to compute the remaining gas cost after above gasleft().
    // See OffchainAggregatorBilling.accountingGasCost docstring for more information.
    //
    // gasUsedInAccounting = gasLeft - gasleft();
  }
  /*
   * Payee management
   */
  /**
   * @notice emitted when a transfer of an oracle's payee address has been initiated
   * @param transmitter address from which the oracle sends reports to the transmit method
   * @param current the payeee address for the oracle, prior to this setting
   * @param proposed the proposed new payee address for the oracle
   */
  event PayeeshipTransferRequested(
    address indexed transmitter,
    address indexed current,
    address indexed proposed
  );
  /**
   * @notice emitted when a transfer of an oracle's payee address has been completed
   * @param transmitter address from which the oracle sends reports to the transmit method
   * @param current the payeee address for the oracle, prior to this setting
   */
  event PayeeshipTransferred(
    address indexed transmitter,
    address indexed previous,
    address indexed current
  );
  /**
   * @notice sets the payees for transmitting addresses
   * @param _transmitters addresses oracles use to transmit the reports
   * @param _payees addresses of payees corresponding to list of transmitters
   * @dev must be called by owner
   * @dev cannot be used to change payee addresses, only to initially populate them
   */
  function setPayees(
    address[] calldata _transmitters,
    address[] calldata _payees
  )
    external
    onlyOwner()
  {
    require(_transmitters.length == _payees.length, "transmitters.size != payees.size");
    for (uint i = 0; i < _transmitters.length; i++) {
      address transmitter = _transmitters[i];
      address payee = _payees[i];
      address currentPayee = s_payees[transmitter];
      bool zeroedOut = currentPayee == address(0);
      require(zeroedOut || currentPayee == payee, "payee already set");
      s_payees[transmitter] = payee;
      if (currentPayee != payee) {
        emit PayeeshipTransferred(transmitter, currentPayee, payee);
      }
    }
  }
  /**
   * @notice first step of payeeship transfer (safe transfer pattern)
   * @param _transmitter transmitter address of oracle whose payee is changing
   * @param _proposed new payee address
   * @dev can only be called by payee address
   */
  function transferPayeeship(
    address _transmitter,
    address _proposed
  )
    external
  {
      require(msg.sender == s_payees[_transmitter], "only current payee can update");
      require(msg.sender != _proposed, "cannot transfer to self");
      address previousProposed = s_proposedPayees[_transmitter];
      s_proposedPayees[_transmitter] = _proposed;
      if (previousProposed != _proposed) {
        emit PayeeshipTransferRequested(_transmitter, msg.sender, _proposed);
      }
  }
  /**
   * @notice second step of payeeship transfer (safe transfer pattern)
   * @param _transmitter transmitter address of oracle whose payee is changing
   * @dev can only be called by proposed new payee address
   */
  function acceptPayeeship(
    address _transmitter
  )
    external
  {
    require(msg.sender == s_proposedPayees[_transmitter], "only proposed payees can accept");
    address currentPayee = s_payees[_transmitter];
    s_payees[_transmitter] = msg.sender;
    s_proposedPayees[_transmitter] = address(0);
    emit PayeeshipTransferred(_transmitter, currentPayee, msg.sender);
  }
  /*
   * Helper functions
   */
  function saturatingAddUint16(uint16 _x, uint16 _y)
    internal
    pure
    returns (uint16)
  {
    return uint16(min(uint256(_x)+uint256(_y), maxUint16));
  }
  function min(uint256 a, uint256 b)
    internal
    pure
    returns (uint256)
  {
    if (a < b) { return a; }
    return b;
  }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
/**
 * @title The Owned contract
 * @notice A contract with helpers for basic contract ownership.
 */
contract Owned {
  address payable public owner;
  address private pendingOwner;
  event OwnershipTransferRequested(
    address indexed from,
    address indexed to
  );
  event OwnershipTransferred(
    address indexed from,
    address indexed to
  );
  constructor() {
    owner = msg.sender;
  }
  /**
   * @dev Allows an owner to begin transferring ownership to a new address,
   * pending.
   */
  function transferOwnership(address _to)
    external
    onlyOwner()
  {
    pendingOwner = _to;
    emit OwnershipTransferRequested(owner, _to);
  }
  /**
   * @dev Allows an ownership transfer to be completed by the recipient.
   */
  function acceptOwnership()
    external
  {
    require(msg.sender == pendingOwner, "Must be proposed owner");
    address oldOwner = owner;
    owner = msg.sender;
    pendingOwner = address(0);
    emit OwnershipTransferred(oldOwner, msg.sender);
  }
  /**
   * @dev Reverts if called by anyone other than the contract owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner, "Only callable by owner");
    _;
  }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./SimpleWriteAccessController.sol";
/**
 * @title SimpleReadAccessController
 * @notice Gives access to:
 * - any externally owned account (note that offchain actors can always read
 * any contract storage regardless of onchain access control measures, so this
 * does not weaken the access control while improving usability)
 * - accounts explicitly added to an access list
 * @dev SimpleReadAccessController is not suitable for access controlling writes
 * since it grants any externally owned account access! See
 * SimpleWriteAccessController for that.
 */
contract SimpleReadAccessController is SimpleWriteAccessController {
  /**
   * @notice Returns the access of an address
   * @param _user The address to query
   */
  function hasAccess(
    address _user,
    bytes memory _calldata
  )
    public
    view
    virtual
    override
    returns (bool)
  {
    return super.hasAccess(_user, _calldata) || _user == tx.origin;
  }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./Owned.sol";
import "./AccessControllerInterface.sol";
/**
 * @title SimpleWriteAccessController
 * @notice Gives access to accounts explicitly added to an access list by the
 * controller's owner.
 * @dev does not make any special permissions for externally, see
 * SimpleReadAccessController for that.
 */
contract SimpleWriteAccessController is AccessControllerInterface, Owned {
  bool public checkEnabled;
  mapping(address => bool) internal accessList;
  event AddedAccess(address user);
  event RemovedAccess(address user);
  event CheckAccessEnabled();
  event CheckAccessDisabled();
  constructor()
  {
    checkEnabled = true;
  }
  /**
   * @notice Returns the access of an address
   * @param _user The address to query
   */
  function hasAccess(
    address _user,
    bytes memory
  )
    public
    view
    virtual
    override
    returns (bool)
  {
    return accessList[_user] || !checkEnabled;
  }
  /**
   * @notice Adds an address to the access list
   * @param _user The address to add
   */
  function addAccess(address _user) external onlyOwner() {
    addAccessInternal(_user);
  }
  function addAccessInternal(address _user) internal {
    if (!accessList[_user]) {
      accessList[_user] = true;
      emit AddedAccess(_user);
    }
  }
  /**
   * @notice Removes an address from the access list
   * @param _user The address to remove
   */
  function removeAccess(address _user)
    external
    onlyOwner()
  {
    if (accessList[_user]) {
      accessList[_user] = false;
      emit RemovedAccess(_user);
    }
  }
  /**
   * @notice makes the access check enforced
   */
  function enableAccessCheck()
    external
    onlyOwner()
  {
    if (!checkEnabled) {
      checkEnabled = true;
      emit CheckAccessEnabled();
    }
  }
  /**
   * @notice makes the access check unenforced
   */
  function disableAccessCheck()
    external
    onlyOwner()
  {
    if (checkEnabled) {
      checkEnabled = false;
      emit CheckAccessDisabled();
    }
  }
  /**
   * @dev reverts if the caller does not have access
   */
  modifier checkAccess() {
    require(hasAccess(msg.sender, msg.data), "No access");
    _;
  }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
abstract contract TypeAndVersionInterface{
  function typeAndVersion()
    external
    pure
    virtual
    returns (string memory);
}