// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
// OpenZeppelin contracts
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
// LooksRare interfaces
import {ICurrencyManager} from "./interfaces/ICurrencyManager.sol";
import {IExecutionManager} from "./interfaces/IExecutionManager.sol";
import {IExecutionStrategy} from "./interfaces/IExecutionStrategy.sol";
import {IRoyaltyFeeManager} from "./interfaces/IRoyaltyFeeManager.sol";
import {ILooksRareExchange} from "./interfaces/ILooksRareExchange.sol";
import {ITransferManagerNFT} from "./interfaces/ITransferManagerNFT.sol";
import {ITransferSelectorNFT} from "./interfaces/ITransferSelectorNFT.sol";
import {IWETH} from "./interfaces/IWETH.sol";
// LooksRare libraries
import {OrderTypes} from "./libraries/OrderTypes.sol";
import {SignatureChecker} from "./libraries/SignatureChecker.sol";
/**
 * @title LooksRareExchange
 * @notice It is the core contract of the LooksRare exchange.
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRAR'''''''''''''''''''''''''''''''''''OOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKS:.                                        .;OOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOO,.                                            .,KSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRAREL'                ..',;:LOOKS::;,'..                'RARELOOKSRARELOOKSR
LOOKSRARELOOKSRAR.              .,:LOOKSRARELOOKSRARELO:,.              .RELOOKSRARELOOKSR
LOOKSRARELOOKS:.             .;RARELOOKSRARELOOKSRARELOOKSl;.             .:OOKSRARELOOKSR
LOOKSRARELOO;.            .'OKSRARELOOKSRARELOOKSRARELOOKSRARE'.            .;KSRARELOOKSR
LOOKSRAREL,.            .,LOOKSRARELOOK:;;:"""":;;;lELOOKSRARELO,.            .,RARELOOKSR
LOOKSRAR.             .;okLOOKSRAREx:.              .;OOKSRARELOOK;.             .RELOOKSR
LOOKS:.             .:dOOOLOOKSRARE'      .''''..     .OKSRARELOOKSR:.             .LOOKSR
LOx;.             .cKSRARELOOKSRAR'     'LOOKSRAR'     .KSRARELOOKSRARc..            .OKSR
L;.             .cxOKSRARELOOKSRAR.    .LOOKS.RARE'     ;kRARELOOKSRARExc.             .;R
LO'             .;oOKSRARELOOKSRAl.    .LOOKS.RARE.     :kRARELOOKSRAREo;.             'SR
LOOK;.            .,KSRARELOOKSRAx,     .;LOOKSR;.     .oSRARELOOKSRAo,.            .;OKSR
LOOKSk:.            .'RARELOOKSRARd;.      ....       'oOOOOOOOOOOxc'.            .:LOOKSR
LOOKSRARc.             .:dLOOKSRAREko;.            .,lxOOOOOOOOOd:.             .ARELOOKSR
LOOKSRARELo'             .;oOKSRARELOOxoc;,....,;:ldkOOOOOOOOkd;.             'SRARELOOKSR
LOOKSRARELOOd,.            .,lSRARELOOKSRARELOOKSRARELOOKSRkl,.            .,OKSRARELOOKSR
LOOKSRARELOOKSx;.            ..;oxELOOKSRARELOOKSRARELOkxl:..            .:LOOKSRARELOOKSR
LOOKSRARELOOKSRARc.              .':cOKSRARELOOKSRALOc;'.              .ARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELl'                 ...'',,,,''...                 'SRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOo,.                                          .,OKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSx;.                                      .;xOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLO:.                                  .:SRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKl.                              .lOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRo'.                        .'oLOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARd;.                    .;xRELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELO:.                .:kRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKl.            .cOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRo'        'oLOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARE,.  .,dRELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
 */
contract LooksRareExchange is ILooksRareExchange, ReentrancyGuard, Ownable {
    using SafeERC20 for IERC20;
    using OrderTypes for OrderTypes.MakerOrder;
    using OrderTypes for OrderTypes.TakerOrder;
    address public immutable WETH;
    bytes32 public immutable DOMAIN_SEPARATOR;
    address public protocolFeeRecipient;
    ICurrencyManager public currencyManager;
    IExecutionManager public executionManager;
    IRoyaltyFeeManager public royaltyFeeManager;
    ITransferSelectorNFT public transferSelectorNFT;
    mapping(address => uint256) public userMinOrderNonce;
    mapping(address => mapping(uint256 => bool)) private _isUserOrderNonceExecutedOrCancelled;
    event CancelAllOrders(address indexed user, uint256 newMinNonce);
    event CancelMultipleOrders(address indexed user, uint256[] orderNonces);
    event NewCurrencyManager(address indexed currencyManager);
    event NewExecutionManager(address indexed executionManager);
    event NewProtocolFeeRecipient(address indexed protocolFeeRecipient);
    event NewRoyaltyFeeManager(address indexed royaltyFeeManager);
    event NewTransferSelectorNFT(address indexed transferSelectorNFT);
    event RoyaltyPayment(
        address indexed collection,
        uint256 indexed tokenId,
        address indexed royaltyRecipient,
        address currency,
        uint256 amount
    );
    event TakerAsk(
        bytes32 orderHash, // bid hash of the maker order
        uint256 orderNonce, // user order nonce
        address indexed taker, // sender address for the taker ask order
        address indexed maker, // maker address of the initial bid order
        address indexed strategy, // strategy that defines the execution
        address currency, // currency address
        address collection, // collection address
        uint256 tokenId, // tokenId transferred
        uint256 amount, // amount of tokens transferred
        uint256 price // final transacted price
    );
    event TakerBid(
        bytes32 orderHash, // ask hash of the maker order
        uint256 orderNonce, // user order nonce
        address indexed taker, // sender address for the taker bid order
        address indexed maker, // maker address of the initial ask order
        address indexed strategy, // strategy that defines the execution
        address currency, // currency address
        address collection, // collection address
        uint256 tokenId, // tokenId transferred
        uint256 amount, // amount of tokens transferred
        uint256 price // final transacted price
    );
    /**
     * @notice Constructor
     * @param _currencyManager currency manager address
     * @param _executionManager execution manager address
     * @param _royaltyFeeManager royalty fee manager address
     * @param _WETH wrapped ether address (for other chains, use wrapped native asset)
     * @param _protocolFeeRecipient protocol fee recipient
     */
    constructor(
        address _currencyManager,
        address _executionManager,
        address _royaltyFeeManager,
        address _WETH,
        address _protocolFeeRecipient
    ) {
        // Calculate the domain separator
        DOMAIN_SEPARATOR = keccak256(
            abi.encode(
                0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f, // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                0xda9101ba92939daf4bb2e18cd5f942363b9297fbc3232c9dd964abb1fb70ed71, // keccak256("LooksRareExchange")
                0xc89efdaa54c0f20c7adf612882df0950f5a951637e0307cdcb4c672f298b8bc6, // keccak256(bytes("1")) for versionId = 1
                block.chainid,
                address(this)
            )
        );
        currencyManager = ICurrencyManager(_currencyManager);
        executionManager = IExecutionManager(_executionManager);
        royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
        WETH = _WETH;
        protocolFeeRecipient = _protocolFeeRecipient;
    }
    /**
     * @notice Cancel all pending orders for a sender
     * @param minNonce minimum user nonce
     */
    function cancelAllOrdersForSender(uint256 minNonce) external {
        require(minNonce > userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
        require(minNonce < userMinOrderNonce[msg.sender] + 500000, "Cancel: Cannot cancel more orders");
        userMinOrderNonce[msg.sender] = minNonce;
        emit CancelAllOrders(msg.sender, minNonce);
    }
    /**
     * @notice Cancel maker orders
     * @param orderNonces array of order nonces
     */
    function cancelMultipleMakerOrders(uint256[] calldata orderNonces) external {
        require(orderNonces.length > 0, "Cancel: Cannot be empty");
        for (uint256 i = 0; i < orderNonces.length; i++) {
            require(orderNonces[i] >= userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
            _isUserOrderNonceExecutedOrCancelled[msg.sender][orderNonces[i]] = true;
        }
        emit CancelMultipleOrders(msg.sender, orderNonces);
    }
    /**
     * @notice Match ask with a taker bid order using ETH
     * @param takerBid taker bid order
     * @param makerAsk maker ask order
     */
    function matchAskWithTakerBidUsingETHAndWETH(
        OrderTypes.TakerOrder calldata takerBid,
        OrderTypes.MakerOrder calldata makerAsk
    ) external payable override nonReentrant {
        require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
        require(makerAsk.currency == WETH, "Order: Currency must be WETH");
        require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
        // If not enough ETH to cover the price, use WETH
        if (takerBid.price > msg.value) {
            IERC20(WETH).safeTransferFrom(msg.sender, address(this), (takerBid.price - msg.value));
        } else {
            require(takerBid.price == msg.value, "Order: Msg.value too high");
        }
        // Wrap ETH sent to this contract
        IWETH(WETH).deposit{value: msg.value}();
        // Check the maker ask order
        bytes32 askHash = makerAsk.hash();
        _validateOrder(makerAsk, askHash);
        // Retrieve execution parameters
        (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
            .canExecuteTakerBid(takerBid, makerAsk);
        require(isExecutionValid, "Strategy: Execution invalid");
        // Update maker ask order status to true (prevents replay)
        _isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
        // Execution part 1/2
        _transferFeesAndFundsWithWETH(
            makerAsk.strategy,
            makerAsk.collection,
            tokenId,
            makerAsk.signer,
            takerBid.price,
            makerAsk.minPercentageToAsk
        );
        // Execution part 2/2
        _transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
        emit TakerBid(
            askHash,
            makerAsk.nonce,
            takerBid.taker,
            makerAsk.signer,
            makerAsk.strategy,
            makerAsk.currency,
            makerAsk.collection,
            tokenId,
            amount,
            takerBid.price
        );
    }
    /**
     * @notice Match a takerBid with a matchAsk
     * @param takerBid taker bid order
     * @param makerAsk maker ask order
     */
    function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external
        override
        nonReentrant
    {
        require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
        require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
        // Check the maker ask order
        bytes32 askHash = makerAsk.hash();
        _validateOrder(makerAsk, askHash);
        (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
            .canExecuteTakerBid(takerBid, makerAsk);
        require(isExecutionValid, "Strategy: Execution invalid");
        // Update maker ask order status to true (prevents replay)
        _isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
        // Execution part 1/2
        _transferFeesAndFunds(
            makerAsk.strategy,
            makerAsk.collection,
            tokenId,
            makerAsk.currency,
            msg.sender,
            makerAsk.signer,
            takerBid.price,
            makerAsk.minPercentageToAsk
        );
        // Execution part 2/2
        _transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
        emit TakerBid(
            askHash,
            makerAsk.nonce,
            takerBid.taker,
            makerAsk.signer,
            makerAsk.strategy,
            makerAsk.currency,
            makerAsk.collection,
            tokenId,
            amount,
            takerBid.price
        );
    }
    /**
     * @notice Match a takerAsk with a makerBid
     * @param takerAsk taker ask order
     * @param makerBid maker bid order
     */
    function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        override
        nonReentrant
    {
        require((!makerBid.isOrderAsk) && (takerAsk.isOrderAsk), "Order: Wrong sides");
        require(msg.sender == takerAsk.taker, "Order: Taker must be the sender");
        // Check the maker bid order
        bytes32 bidHash = makerBid.hash();
        _validateOrder(makerBid, bidHash);
        (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerBid.strategy)
            .canExecuteTakerAsk(takerAsk, makerBid);
        require(isExecutionValid, "Strategy: Execution invalid");
        // Update maker bid order status to true (prevents replay)
        _isUserOrderNonceExecutedOrCancelled[makerBid.signer][makerBid.nonce] = true;
        // Execution part 1/2
        _transferNonFungibleToken(makerBid.collection, msg.sender, makerBid.signer, tokenId, amount);
        // Execution part 2/2
        _transferFeesAndFunds(
            makerBid.strategy,
            makerBid.collection,
            tokenId,
            makerBid.currency,
            makerBid.signer,
            takerAsk.taker,
            takerAsk.price,
            takerAsk.minPercentageToAsk
        );
        emit TakerAsk(
            bidHash,
            makerBid.nonce,
            takerAsk.taker,
            makerBid.signer,
            makerBid.strategy,
            makerBid.currency,
            makerBid.collection,
            tokenId,
            amount,
            takerAsk.price
        );
    }
    /**
     * @notice Update currency manager
     * @param _currencyManager new currency manager address
     */
    function updateCurrencyManager(address _currencyManager) external onlyOwner {
        require(_currencyManager != address(0), "Owner: Cannot be null address");
        currencyManager = ICurrencyManager(_currencyManager);
        emit NewCurrencyManager(_currencyManager);
    }
    /**
     * @notice Update execution manager
     * @param _executionManager new execution manager address
     */
    function updateExecutionManager(address _executionManager) external onlyOwner {
        require(_executionManager != address(0), "Owner: Cannot be null address");
        executionManager = IExecutionManager(_executionManager);
        emit NewExecutionManager(_executionManager);
    }
    /**
     * @notice Update protocol fee and recipient
     * @param _protocolFeeRecipient new recipient for protocol fees
     */
    function updateProtocolFeeRecipient(address _protocolFeeRecipient) external onlyOwner {
        protocolFeeRecipient = _protocolFeeRecipient;
        emit NewProtocolFeeRecipient(_protocolFeeRecipient);
    }
    /**
     * @notice Update royalty fee manager
     * @param _royaltyFeeManager new fee manager address
     */
    function updateRoyaltyFeeManager(address _royaltyFeeManager) external onlyOwner {
        require(_royaltyFeeManager != address(0), "Owner: Cannot be null address");
        royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
        emit NewRoyaltyFeeManager(_royaltyFeeManager);
    }
    /**
     * @notice Update transfer selector NFT
     * @param _transferSelectorNFT new transfer selector address
     */
    function updateTransferSelectorNFT(address _transferSelectorNFT) external onlyOwner {
        require(_transferSelectorNFT != address(0), "Owner: Cannot be null address");
        transferSelectorNFT = ITransferSelectorNFT(_transferSelectorNFT);
        emit NewTransferSelectorNFT(_transferSelectorNFT);
    }
    /**
     * @notice Check whether user order nonce is executed or cancelled
     * @param user address of user
     * @param orderNonce nonce of the order
     */
    function isUserOrderNonceExecutedOrCancelled(address user, uint256 orderNonce) external view returns (bool) {
        return _isUserOrderNonceExecutedOrCancelled[user][orderNonce];
    }
    /**
     * @notice Transfer fees and funds to royalty recipient, protocol, and seller
     * @param strategy address of the execution strategy
     * @param collection non fungible token address for the transfer
     * @param tokenId tokenId
     * @param currency currency being used for the purchase (e.g., WETH/USDC)
     * @param from sender of the funds
     * @param to seller's recipient
     * @param amount amount being transferred (in currency)
     * @param minPercentageToAsk minimum percentage of the gross amount that goes to ask
     */
    function _transferFeesAndFunds(
        address strategy,
        address collection,
        uint256 tokenId,
        address currency,
        address from,
        address to,
        uint256 amount,
        uint256 minPercentageToAsk
    ) internal {
        // Initialize the final amount that is transferred to seller
        uint256 finalSellerAmount = amount;
        // 1. Protocol fee
        {
            uint256 protocolFeeAmount = _calculateProtocolFee(strategy, amount);
            // Check if the protocol fee is different than 0 for this strategy
            if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
                IERC20(currency).safeTransferFrom(from, protocolFeeRecipient, protocolFeeAmount);
                finalSellerAmount -= protocolFeeAmount;
            }
        }
        // 2. Royalty fee
        {
            (address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
                .calculateRoyaltyFeeAndGetRecipient(collection, tokenId, amount);
            // Check if there is a royalty fee and that it is different to 0
            if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
                IERC20(currency).safeTransferFrom(from, royaltyFeeRecipient, royaltyFeeAmount);
                finalSellerAmount -= royaltyFeeAmount;
                emit RoyaltyPayment(collection, tokenId, royaltyFeeRecipient, currency, royaltyFeeAmount);
            }
        }
        require((finalSellerAmount * 10000) >= (minPercentageToAsk * amount), "Fees: Higher than expected");
        // 3. Transfer final amount (post-fees) to seller
        {
            IERC20(currency).safeTransferFrom(from, to, finalSellerAmount);
        }
    }
    /**
     * @notice Transfer fees and funds to royalty recipient, protocol, and seller
     * @param strategy address of the execution strategy
     * @param collection non fungible token address for the transfer
     * @param tokenId tokenId
     * @param to seller's recipient
     * @param amount amount being transferred (in currency)
     * @param minPercentageToAsk minimum percentage of the gross amount that goes to ask
     */
    function _transferFeesAndFundsWithWETH(
        address strategy,
        address collection,
        uint256 tokenId,
        address to,
        uint256 amount,
        uint256 minPercentageToAsk
    ) internal {
        // Initialize the final amount that is transferred to seller
        uint256 finalSellerAmount = amount;
        // 1. Protocol fee
        {
            uint256 protocolFeeAmount = _calculateProtocolFee(strategy, amount);
            // Check if the protocol fee is different than 0 for this strategy
            if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
                IERC20(WETH).safeTransfer(protocolFeeRecipient, protocolFeeAmount);
                finalSellerAmount -= protocolFeeAmount;
            }
        }
        // 2. Royalty fee
        {
            (address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
                .calculateRoyaltyFeeAndGetRecipient(collection, tokenId, amount);
            // Check if there is a royalty fee and that it is different to 0
            if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
                IERC20(WETH).safeTransfer(royaltyFeeRecipient, royaltyFeeAmount);
                finalSellerAmount -= royaltyFeeAmount;
                emit RoyaltyPayment(collection, tokenId, royaltyFeeRecipient, address(WETH), royaltyFeeAmount);
            }
        }
        require((finalSellerAmount * 10000) >= (minPercentageToAsk * amount), "Fees: Higher than expected");
        // 3. Transfer final amount (post-fees) to seller
        {
            IERC20(WETH).safeTransfer(to, finalSellerAmount);
        }
    }
    /**
     * @notice Transfer NFT
     * @param collection address of the token collection
     * @param from address of the sender
     * @param to address of the recipient
     * @param tokenId tokenId
     * @param amount amount of tokens (1 for ERC721, 1+ for ERC1155)
     * @dev For ERC721, amount is not used
     */
    function _transferNonFungibleToken(
        address collection,
        address from,
        address to,
        uint256 tokenId,
        uint256 amount
    ) internal {
        // Retrieve the transfer manager address
        address transferManager = transferSelectorNFT.checkTransferManagerForToken(collection);
        // If no transfer manager found, it returns address(0)
        require(transferManager != address(0), "Transfer: No NFT transfer manager available");
        // If one is found, transfer the token
        ITransferManagerNFT(transferManager).transferNonFungibleToken(collection, from, to, tokenId, amount);
    }
    /**
     * @notice Calculate protocol fee for an execution strategy
     * @param executionStrategy strategy
     * @param amount amount to transfer
     */
    function _calculateProtocolFee(address executionStrategy, uint256 amount) internal view returns (uint256) {
        uint256 protocolFee = IExecutionStrategy(executionStrategy).viewProtocolFee();
        return (protocolFee * amount) / 10000;
    }
    /**
     * @notice Verify the validity of the maker order
     * @param makerOrder maker order
     * @param orderHash computed hash for the order
     */
    function _validateOrder(OrderTypes.MakerOrder calldata makerOrder, bytes32 orderHash) internal view {
        // Verify whether order nonce has expired
        require(
            (!_isUserOrderNonceExecutedOrCancelled[makerOrder.signer][makerOrder.nonce]) &&
                (makerOrder.nonce >= userMinOrderNonce[makerOrder.signer]),
            "Order: Matching order expired"
        );
        // Verify the signer is not address(0)
        require(makerOrder.signer != address(0), "Order: Invalid signer");
        // Verify the amount is not 0
        require(makerOrder.amount > 0, "Order: Amount cannot be 0");
        // Verify the validity of the signature
        require(
            SignatureChecker.verify(
                orderHash,
                makerOrder.signer,
                makerOrder.v,
                makerOrder.r,
                makerOrder.s,
                DOMAIN_SEPARATOR
            ),
            "Signature: Invalid"
        );
        // Verify whether the currency is whitelisted
        require(currencyManager.isCurrencyWhitelisted(makerOrder.currency), "Currency: Not whitelisted");
        // Verify whether strategy can be executed
        require(executionManager.isStrategyWhitelisted(makerOrder.strategy), "Strategy: Not whitelisted");
    }
}
// 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 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor() {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;
    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ICurrencyManager {
    function addCurrency(address currency) external;
    function removeCurrency(address currency) external;
    function isCurrencyWhitelisted(address currency) external view returns (bool);
    function viewWhitelistedCurrencies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
    function viewCountWhitelistedCurrencies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IExecutionManager {
    function addStrategy(address strategy) external;
    function removeStrategy(address strategy) external;
    function isStrategyWhitelisted(address strategy) external view returns (bool);
    function viewWhitelistedStrategies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
    function viewCountWhitelistedStrategies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface IExecutionStrategy {
    function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function viewProtocolFee() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IRoyaltyFeeManager {
    function calculateRoyaltyFeeAndGetRecipient(
        address collection,
        uint256 tokenId,
        uint256 amount
    ) external view returns (address, uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface ILooksRareExchange {
    function matchAskWithTakerBidUsingETHAndWETH(
        OrderTypes.TakerOrder calldata takerBid,
        OrderTypes.MakerOrder calldata makerAsk
    ) external payable;
    function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external;
    function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferManagerNFT {
    function transferNonFungibleToken(
        address collection,
        address from,
        address to,
        uint256 tokenId,
        uint256 amount
    ) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferSelectorNFT {
    function checkTransferManagerForToken(address collection) external view returns (address);
}
// SPDX-License-Identifier: GNU
pragma solidity >=0.5.0;
interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint256 value) external returns (bool);
    function withdraw(uint256) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @title OrderTypes
 * @notice This library contains order types for the LooksRare exchange.
 */
library OrderTypes {
    // keccak256("MakerOrder(bool isOrderAsk,address signer,address collection,uint256 price,uint256 tokenId,uint256 amount,address strategy,address currency,uint256 nonce,uint256 startTime,uint256 endTime,uint256 minPercentageToAsk,bytes params)")
    bytes32 internal constant MAKER_ORDER_HASH = 0x40261ade532fa1d2c7293df30aaadb9b3c616fae525a0b56d3d411c841a85028;
    struct MakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address signer; // signer of the maker order
        address collection; // collection address
        uint256 price; // price (used as )
        uint256 tokenId; // id of the token
        uint256 amount; // amount of tokens to sell/purchase (must be 1 for ERC721, 1+ for ERC1155)
        address strategy; // strategy for trade execution (e.g., DutchAuction, StandardSaleForFixedPrice)
        address currency; // currency (e.g., WETH)
        uint256 nonce; // order nonce (must be unique unless new maker order is meant to override existing one e.g., lower ask price)
        uint256 startTime; // startTime in timestamp
        uint256 endTime; // endTime in timestamp
        uint256 minPercentageToAsk; // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // additional parameters
        uint8 v; // v: parameter (27 or 28)
        bytes32 r; // r: parameter
        bytes32 s; // s: parameter
    }
    struct TakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address taker; // msg.sender
        uint256 price; // final price for the purchase
        uint256 tokenId;
        uint256 minPercentageToAsk; // // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // other params (e.g., tokenId)
    }
    function hash(MakerOrder memory makerOrder) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    MAKER_ORDER_HASH,
                    makerOrder.isOrderAsk,
                    makerOrder.signer,
                    makerOrder.collection,
                    makerOrder.price,
                    makerOrder.tokenId,
                    makerOrder.amount,
                    makerOrder.strategy,
                    makerOrder.currency,
                    makerOrder.nonce,
                    makerOrder.startTime,
                    makerOrder.endTime,
                    makerOrder.minPercentageToAsk,
                    keccak256(makerOrder.params)
                )
            );
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {IERC1271} from "@openzeppelin/contracts/interfaces/IERC1271.sol";
/**
 * @title SignatureChecker
 * @notice This library allows verification of signatures for both EOAs and contracts.
 */
library SignatureChecker {
    /**
     * @notice Recovers the signer of a signature (for EOA)
     * @param hash the hash containing the signed mesage
     * @param v parameter (27 or 28). This prevents maleability since the public key recovery equation has two possible solutions.
     * @param r parameter
     * @param s parameter
     */
    function recover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address) {
        // https://ethereum.stackexchange.com/questions/83174/is-it-best-practice-to-check-signature-malleability-in-ecrecover
        // https://crypto.iacr.org/2019/affevents/wac/medias/Heninger-BiasedNonceSense.pdf
        require(
            uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
            "Signature: Invalid s parameter"
        );
        require(v == 27 || v == 28, "Signature: Invalid v parameter");
        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        require(signer != address(0), "Signature: Invalid signer");
        return signer;
    }
    /**
     * @notice Returns whether the signer matches the signed message
     * @param hash the hash containing the signed mesage
     * @param signer the signer address to confirm message validity
     * @param v parameter (27 or 28)
     * @param r parameter
     * @param s parameter
     * @param domainSeparator paramer to prevent signature being executed in other chains and environments
     * @return true --> if valid // false --> if invalid
     */
    function verify(
        bytes32 hash,
        address signer,
        uint8 v,
        bytes32 r,
        bytes32 s,
        bytes32 domainSeparator
    ) internal view returns (bool) {
        // \\x19\\x01 is the standardized encoding prefix
        // https://eips.ethereum.org/EIPS/eip-712#specification
        bytes32 digest = keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, hash));
        if (Address.isContract(signer)) {
            // 0x1626ba7e is the interfaceId for signature contracts (see IERC1271)
            return IERC1271(signer).isValidSignature(digest, abi.encodePacked(r, s, v)) == 0x1626ba7e;
        } else {
            return recover(digest, v, r, s) == signer;
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
pragma solidity ^0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC1271 standard signature validation method for
 * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
 *
 * _Available since v4.1._
 */
interface IERC1271 {
    /**
     * @dev Should return whether the signature provided is valid for the provided data
     * @param hash      Hash of the data to be signed
     * @param signature Signature byte array associated with _data
     */
    function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {EnumerableSet} from "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import {ICurrencyManager} from "./interfaces/ICurrencyManager.sol";
/**
 * @title CurrencyManager
 * @notice It allows adding/removing currencies for trading on the LooksRare exchange.
 */
contract CurrencyManager is ICurrencyManager, Ownable {
    using EnumerableSet for EnumerableSet.AddressSet;
    EnumerableSet.AddressSet private _whitelistedCurrencies;
    event CurrencyRemoved(address indexed currency);
    event CurrencyWhitelisted(address indexed currency);
    /**
     * @notice Add a currency in the system
     * @param currency address of the currency to add
     */
    function addCurrency(address currency) external override onlyOwner {
        require(!_whitelistedCurrencies.contains(currency), "Currency: Already whitelisted");
        _whitelistedCurrencies.add(currency);
        emit CurrencyWhitelisted(currency);
    }
    /**
     * @notice Remove a currency from the system
     * @param currency address of the currency to remove
     */
    function removeCurrency(address currency) external override onlyOwner {
        require(_whitelistedCurrencies.contains(currency), "Currency: Not whitelisted");
        _whitelistedCurrencies.remove(currency);
        emit CurrencyRemoved(currency);
    }
    /**
     * @notice Returns if a currency is in the system
     * @param currency address of the currency
     */
    function isCurrencyWhitelisted(address currency) external view override returns (bool) {
        return _whitelistedCurrencies.contains(currency);
    }
    /**
     * @notice View number of whitelisted currencies
     */
    function viewCountWhitelistedCurrencies() external view override returns (uint256) {
        return _whitelistedCurrencies.length();
    }
    /**
     * @notice See whitelisted currencies in the system
     * @param cursor cursor (should start at 0 for first request)
     * @param size size of the response (e.g., 50)
     */
    function viewWhitelistedCurrencies(uint256 cursor, uint256 size)
        external
        view
        override
        returns (address[] memory, uint256)
    {
        uint256 length = size;
        if (length > _whitelistedCurrencies.length() - cursor) {
            length = _whitelistedCurrencies.length() - cursor;
        }
        address[] memory whitelistedCurrencies = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            whitelistedCurrencies[i] = _whitelistedCurrencies.at(cursor + i);
        }
        return (whitelistedCurrencies, cursor + length);
    }
}
// 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/structs/EnumerableSet.sol)
pragma solidity ^0.8.0;
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.
    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            if (lastIndex != toDeleteIndex) {
                bytes32 lastvalue = set._values[lastIndex];
                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
            }
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }
    // Bytes32Set
    struct Bytes32Set {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        return _values(set._inner);
    }
    // AddressSet
    struct AddressSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;
        assembly {
            result := store
        }
        return result;
    }
    // UintSet
    struct UintSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;
        assembly {
            result := store
        }
        return result;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ICurrencyManager {
    function addCurrency(address currency) external;
    function removeCurrency(address currency) external;
    function isCurrencyWhitelisted(address currency) external view returns (bool);
    function viewWhitelistedCurrencies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
    function viewCountWhitelistedCurrencies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {EnumerableSet} from "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import {IExecutionManager} from "./interfaces/IExecutionManager.sol";
/**
 * @title ExecutionManager
 * @notice It allows adding/removing execution strategies for trading on the LooksRare exchange.
 */
contract ExecutionManager is IExecutionManager, Ownable {
    using EnumerableSet for EnumerableSet.AddressSet;
    EnumerableSet.AddressSet private _whitelistedStrategies;
    event StrategyRemoved(address indexed strategy);
    event StrategyWhitelisted(address indexed strategy);
    /**
     * @notice Add an execution strategy in the system
     * @param strategy address of the strategy to add
     */
    function addStrategy(address strategy) external override onlyOwner {
        require(!_whitelistedStrategies.contains(strategy), "Strategy: Already whitelisted");
        _whitelistedStrategies.add(strategy);
        emit StrategyWhitelisted(strategy);
    }
    /**
     * @notice Remove an execution strategy from the system
     * @param strategy address of the strategy to remove
     */
    function removeStrategy(address strategy) external override onlyOwner {
        require(_whitelistedStrategies.contains(strategy), "Strategy: Not whitelisted");
        _whitelistedStrategies.remove(strategy);
        emit StrategyRemoved(strategy);
    }
    /**
     * @notice Returns if an execution strategy is in the system
     * @param strategy address of the strategy
     */
    function isStrategyWhitelisted(address strategy) external view override returns (bool) {
        return _whitelistedStrategies.contains(strategy);
    }
    /**
     * @notice View number of whitelisted strategies
     */
    function viewCountWhitelistedStrategies() external view override returns (uint256) {
        return _whitelistedStrategies.length();
    }
    /**
     * @notice See whitelisted strategies in the system
     * @param cursor cursor (should start at 0 for first request)
     * @param size size of the response (e.g., 50)
     */
    function viewWhitelistedStrategies(uint256 cursor, uint256 size)
        external
        view
        override
        returns (address[] memory, uint256)
    {
        uint256 length = size;
        if (length > _whitelistedStrategies.length() - cursor) {
            length = _whitelistedStrategies.length() - cursor;
        }
        address[] memory whitelistedStrategies = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            whitelistedStrategies[i] = _whitelistedStrategies.at(cursor + i);
        }
        return (whitelistedStrategies, cursor + length);
    }
}
// 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/structs/EnumerableSet.sol)
pragma solidity ^0.8.0;
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.
    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            if (lastIndex != toDeleteIndex) {
                bytes32 lastvalue = set._values[lastIndex];
                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
            }
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }
    // Bytes32Set
    struct Bytes32Set {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        return _values(set._inner);
    }
    // AddressSet
    struct AddressSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;
        assembly {
            result := store
        }
        return result;
    }
    // UintSet
    struct UintSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;
        assembly {
            result := store
        }
        return result;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IExecutionManager {
    function addStrategy(address strategy) external;
    function removeStrategy(address strategy) external;
    function isStrategyWhitelisted(address strategy) external view returns (bool);
    function viewWhitelistedStrategies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
    function viewCountWhitelistedStrategies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
import {IExecutionStrategy} from "../interfaces/IExecutionStrategy.sol";
/**
 * @title StrategyStandardSaleForFixedPrice
 * @notice Strategy that executes an order at a fixed price that
 * can be taken either by a bid or an ask.
 */
contract StrategyStandardSaleForFixedPrice is IExecutionStrategy {
    uint256 public immutable PROTOCOL_FEE;
    /**
     * @notice Constructor
     * @param _protocolFee protocol fee (200 --> 2%, 400 --> 4%)
     */
    constructor(uint256 _protocolFee) {
        PROTOCOL_FEE = _protocolFee;
    }
    /**
     * @notice Check whether a taker ask order can be executed against a maker bid
     * @param takerAsk taker ask order
     * @param makerBid maker bid order
     * @return (whether strategy can be executed, tokenId to execute, amount of tokens to execute)
     */
    function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        view
        override
        returns (
            bool,
            uint256,
            uint256
        )
    {
        return (
            ((makerBid.price == takerAsk.price) &&
                (makerBid.tokenId == takerAsk.tokenId) &&
                (makerBid.startTime <= block.timestamp) &&
                (makerBid.endTime >= block.timestamp)),
            makerBid.tokenId,
            makerBid.amount
        );
    }
    /**
     * @notice Check whether a taker bid order can be executed against a maker ask
     * @param takerBid taker bid order
     * @param makerAsk maker ask order
     * @return (whether strategy can be executed, tokenId to execute, amount of tokens to execute)
     */
    function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external
        view
        override
        returns (
            bool,
            uint256,
            uint256
        )
    {
        return (
            ((makerAsk.price == takerBid.price) &&
                (makerAsk.tokenId == takerBid.tokenId) &&
                (makerAsk.startTime <= block.timestamp) &&
                (makerAsk.endTime >= block.timestamp)),
            makerAsk.tokenId,
            makerAsk.amount
        );
    }
    /**
     * @notice Return protocol fee for this strategy
     * @return protocol fee
     */
    function viewProtocolFee() external view override returns (uint256) {
        return PROTOCOL_FEE;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @title OrderTypes
 * @notice This library contains order types for the LooksRare exchange.
 */
library OrderTypes {
    // keccak256("MakerOrder(bool isOrderAsk,address signer,address collection,uint256 price,uint256 tokenId,uint256 amount,address strategy,address currency,uint256 nonce,uint256 startTime,uint256 endTime,uint256 minPercentageToAsk,bytes params)")
    bytes32 internal constant MAKER_ORDER_HASH = 0x40261ade532fa1d2c7293df30aaadb9b3c616fae525a0b56d3d411c841a85028;
    struct MakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address signer; // signer of the maker order
        address collection; // collection address
        uint256 price; // price (used as )
        uint256 tokenId; // id of the token
        uint256 amount; // amount of tokens to sell/purchase (must be 1 for ERC721, 1+ for ERC1155)
        address strategy; // strategy for trade execution (e.g., DutchAuction, StandardSaleForFixedPrice)
        address currency; // currency (e.g., WETH)
        uint256 nonce; // order nonce (must be unique unless new maker order is meant to override existing one e.g., lower ask price)
        uint256 startTime; // startTime in timestamp
        uint256 endTime; // endTime in timestamp
        uint256 minPercentageToAsk; // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // additional parameters
        uint8 v; // v: parameter (27 or 28)
        bytes32 r; // r: parameter
        bytes32 s; // s: parameter
    }
    struct TakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address taker; // msg.sender
        uint256 price; // final price for the purchase
        uint256 tokenId;
        uint256 minPercentageToAsk; // // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // other params (e.g., tokenId)
    }
    function hash(MakerOrder memory makerOrder) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    MAKER_ORDER_HASH,
                    makerOrder.isOrderAsk,
                    makerOrder.signer,
                    makerOrder.collection,
                    makerOrder.price,
                    makerOrder.tokenId,
                    makerOrder.amount,
                    makerOrder.strategy,
                    makerOrder.currency,
                    makerOrder.nonce,
                    makerOrder.startTime,
                    makerOrder.endTime,
                    makerOrder.minPercentageToAsk,
                    keccak256(makerOrder.params)
                )
            );
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface IExecutionStrategy {
    function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function viewProtocolFee() external view returns (uint256);
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU General Public License is a free, copyleft license for
software and other kinds of works.

  The licenses for most software and other practical works are designed
to take away your freedom to share and change the works.  By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
free programs, and that you know you can do these things.

  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

  For example, if you distribute copies of such a program, whether
gratis or for a fee, you must pass on to the recipients the same
freedoms that you received.  You must make sure that they, too, receive
or can get the source code.  And you must show them these terms so they
know their rights.

  Developers that use the GNU GPL protect your rights with two steps:
(1) assert copyright on the software, and (2) offer you this License
giving you legal permission to copy, distribute and/or modify it.

  For the developers' and authors' protection, the GPL clearly explains
that there is no warranty for this free software.  For both users' and
authors' sake, the GPL requires that modified versions be marked as
changed, so that their problems will not be attributed erroneously to
authors of previous versions.

  Some devices are designed to deny users access to install or run
modified versions of the software inside them, although the manufacturer
can do so.  This is fundamentally incompatible with the aim of
protecting users' freedom to change the software.  The systematic
pattern of such abuse occurs in the area of products for individuals to
use, which is precisely where it is most unacceptable.  Therefore, we
have designed this version of the GPL to prohibit the practice for those
products.  If such problems arise substantially in other domains, we
stand ready to extend this provision to those domains in future versions
of the GPL, as needed to protect the freedom of users.

  Finally, every program is threatened constantly by software patents.
States should not allow patents to restrict development and use of
software on general-purpose computers, but in those that do, we wish to
avoid the special danger that patents applied to a free program could
make it effectively proprietary.  To prevent this, the GPL assures that
patents cannot be used to render the program non-free.

  The precise terms and conditions for copying, distribution and
modification follow.

                       TERMS AND CONDITIONS

  0. Definitions.

  "This License" refers to version 3 of the GNU General Public License.

  "Copyright" also means copyright-like laws that apply to other kinds of
works, such as semiconductor masks.

  "The Program" refers to any copyrightable work licensed under this
License.  Each licensee is addressed as "you".  "Licensees" and
"recipients" may be individuals or organizations.

  To "modify" a work means to copy from or adapt all or part of the work
in a fashion requiring copyright permission, other than the making of an
exact copy.  The resulting work is called a "modified version" of the
earlier work or a work "based on" the earlier work.

  A "covered work" means either the unmodified Program or a work based
on the Program.

  To "propagate" a work means to do anything with it that, without
permission, would make you directly or secondarily liable for
infringement under applicable copyright law, except executing it on a
computer or modifying a private copy.  Propagation includes copying,
distribution (with or without modification), making available to the
public, and in some countries other activities as well.

  To "convey" a work means any kind of propagation that enables other
parties to make or receive copies.  Mere interaction with a user through
a computer network, with no transfer of a copy, is not conveying.

  An interactive user interface displays "Appropriate Legal Notices"
to the extent that it includes a convenient and prominently visible
feature that (1) displays an appropriate copyright notice, and (2)
tells the user that there is no warranty for the work (except to the
extent that warranties are provided), that licensees may convey the
work under this License, and how to view a copy of this License.  If
the interface presents a list of user commands or options, such as a
menu, a prominent item in the list meets this criterion.

  1. Source Code.

  The "source code" for a work means the preferred form of the work
for making modifications to it.  "Object code" means any non-source
form of a work.

  A "Standard Interface" means an interface that either is an official
standard defined by a recognized standards body, or, in the case of
interfaces specified for a particular programming language, one that
is widely used among developers working in that language.

  The "System Libraries" of an executable work include anything, other
than the work as a whole, that (a) is included in the normal form of
packaging a Major Component, but which is not part of that Major
Component, and (b) serves only to enable use of the work with that
Major Component, or to implement a Standard Interface for which an
implementation is available to the public in source code form.  A
"Major Component", in this context, means a major essential component
(kernel, window system, and so on) of the specific operating system
(if any) on which the executable work runs, or a compiler used to
produce the work, or an object code interpreter used to run it.

  The "Corresponding Source" for a work in object code form means all
the source code needed to generate, install, and (for an executable
work) run the object code and to modify the work, including scripts to
control those activities.  However, it does not include the work's
System Libraries, or general-purpose tools or generally available free
programs which are used unmodified in performing those activities but
which are not part of the work.  For example, Corresponding Source
includes interface definition files associated with source files for
the work, and the source code for shared libraries and dynamically
linked subprograms that the work is specifically designed to require,
such as by intimate data communication or control flow between those
subprograms and other parts of the work.

  The Corresponding Source need not include anything that users
can regenerate automatically from other parts of the Corresponding
Source.

  The Corresponding Source for a work in source code form is that
same work.

  2. Basic Permissions.

  All rights granted under this License are granted for the term of
copyright on the Program, and are irrevocable provided the stated
conditions are met.  This License explicitly affirms your unlimited
permission to run the unmodified Program.  The output from running a
covered work is covered by this License only if the output, given its
content, constitutes a covered work.  This License acknowledges your
rights of fair use or other equivalent, as provided by copyright law.

  You may make, run and propagate covered works that you do not
convey, without conditions so long as your license otherwise remains
in force.  You may convey covered works to others for the sole purpose
of having them make modifications exclusively for you, or provide you
with facilities for running those works, provided that you comply with
the terms of this License in conveying all material for which you do
not control copyright.  Those thus making or running the covered works
for you must do so exclusively on your behalf, under your direction
and control, on terms that prohibit them from making any copies of
your copyrighted material outside their relationship with you.

  Conveying under any other circumstances is permitted solely under
the conditions stated below.  Sublicensing is not allowed; section 10
makes it unnecessary.

  3. Protecting Users' Legal Rights From Anti-Circumvention Law.

  No covered work shall be deemed part of an effective technological
measure under any applicable law fulfilling obligations under article
11 of the WIPO copyright treaty adopted on 20 December 1996, or
similar laws prohibiting or restricting circumvention of such
measures.

  When you convey a covered work, you waive any legal power to forbid
circumvention of technological measures to the extent such circumvention
is effected by exercising rights under this License with respect to
the covered work, and you disclaim any intention to limit operation or
modification of the work as a means of enforcing, against the work's
users, your or third parties' legal rights to forbid circumvention of
technological measures.

  4. Conveying Verbatim Copies.

  You may convey verbatim copies of the Program's source code as you
receive it, in any medium, provided that you conspicuously and
appropriately publish on each copy an appropriate copyright notice;
keep intact all notices stating that this License and any
non-permissive terms added in accord with section 7 apply to the code;
keep intact all notices of the absence of any warranty; and give all
recipients a copy of this License along with the Program.

  You may charge any price or no price for each copy that you convey,
and you may offer support or warranty protection for a fee.

  5. Conveying Modified Source Versions.

  You may convey a work based on the Program, or the modifications to
produce it from the Program, in the form of source code under the
terms of section 4, provided that you also meet all of these conditions:

    a) The work must carry prominent notices stating that you modified
    it, and giving a relevant date.

    b) The work must carry prominent notices stating that it is
    released under this License and any conditions added under section
    7.  This requirement modifies the requirement in section 4 to
    "keep intact all notices".

    c) You must license the entire work, as a whole, under this
    License to anyone who comes into possession of a copy.  This
    License will therefore apply, along with any applicable section 7
    additional terms, to the whole of the work, and all its parts,
    regardless of how they are packaged.  This License gives no
    permission to license the work in any other way, but it does not
    invalidate such permission if you have separately received it.

    d) If the work has interactive user interfaces, each must display
    Appropriate Legal Notices; however, if the Program has interactive
    interfaces that do not display Appropriate Legal Notices, your
    work need not make them do so.

  A compilation of a covered work with other separate and independent
works, which are not by their nature extensions of the covered work,
and which are not combined with it such as to form a larger program,
in or on a volume of a storage or distribution medium, is called an
"aggregate" if the compilation and its resulting copyright are not
used to limit the access or legal rights of the compilation's users
beyond what the individual works permit.  Inclusion of a covered work
in an aggregate does not cause this License to apply to the other
parts of the aggregate.

  6. Conveying Non-Source Forms.

  You may convey a covered work in object code form under the terms
of sections 4 and 5, provided that you also convey the
machine-readable Corresponding Source under the terms of this License,
in one of these ways:

    a) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by the
    Corresponding Source fixed on a durable physical medium
    customarily used for software interchange.

    b) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by a
    written offer, valid for at least three years and valid for as
    long as you offer spare parts or customer support for that product
    model, to give anyone who possesses the object code either (1) a
    copy of the Corresponding Source for all the software in the
    product that is covered by this License, on a durable physical
    medium customarily used for software interchange, for a price no
    more than your reasonable cost of physically performing this
    conveying of source, or (2) access to copy the
    Corresponding Source from a network server at no charge.

    c) Convey individual copies of the object code with a copy of the
    written offer to provide the Corresponding Source.  This
    alternative is allowed only occasionally and noncommercially, and
    only if you received the object code with such an offer, in accord
    with subsection 6b.

    d) Convey the object code by offering access from a designated
    place (gratis or for a charge), and offer equivalent access to the
    Corresponding Source in the same way through the same place at no
    further charge.  You need not require recipients to copy the
    Corresponding Source along with the object code.  If the place to
    copy the object code is a network server, the Corresponding Source
    may be on a different server (operated by you or a third party)
    that supports equivalent copying facilities, provided you maintain
    clear directions next to the object code saying where to find the
    Corresponding Source.  Regardless of what server hosts the
    Corresponding Source, you remain obligated to ensure that it is
    available for as long as needed to satisfy these requirements.

    e) Convey the object code using peer-to-peer transmission, provided
    you inform other peers where the object code and Corresponding
    Source of the work are being offered to the general public at no
    charge under subsection 6d.

  A separable portion of the object code, whose source code is excluded
from the Corresponding Source as a System Library, need not be
included in conveying the object code work.

  A "User Product" is either (1) a "consumer product", which means any
tangible personal property which is normally used for personal, family,
or household purposes, or (2) anything designed or sold for incorporation
into a dwelling.  In determining whether a product is a consumer product,
doubtful cases shall be resolved in favor of coverage.  For a particular
product received by a particular user, "normally used" refers to a
typical or common use of that class of product, regardless of the status
of the particular user or of the way in which the particular user
actually uses, or expects or is expected to use, the product.  A product
is a consumer product regardless of whether the product has substantial
commercial, industrial or non-consumer uses, unless such uses represent
the only significant mode of use of the product.

  "Installation Information" for a User Product means any methods,
procedures, authorization keys, or other information required to install
and execute modified versions of a covered work in that User Product from
a modified version of its Corresponding Source.  The information must
suffice to ensure that the continued functioning of the modified object
code is in no case prevented or interfered with solely because
modification has been made.

  If you convey an object code work under this section in, or with, or
specifically for use in, a User Product, and the conveying occurs as
part of a transaction in which the right of possession and use of the
User Product is transferred to the recipient in perpetuity or for a
fixed term (regardless of how the transaction is characterized), the
Corresponding Source conveyed under this section must be accompanied
by the Installation Information.  But this requirement does not apply
if neither you nor any third party retains the ability to install
modified object code on the User Product (for example, the work has
been installed in ROM).

  The requirement to provide Installation Information does not include a
requirement to continue to provide support service, warranty, or updates
for a work that has been modified or installed by the recipient, or for
the User Product in which it has been modified or installed.  Access to a
network may be denied when the modification itself materially and
adversely affects the operation of the network or violates the rules and
protocols for communication across the network.

  Corresponding Source conveyed, and Installation Information provided,
in accord with this section must be in a format that is publicly
documented (and with an implementation available to the public in
source code form), and must require no special password or key for
unpacking, reading or copying.

  7. Additional Terms.

  "Additional permissions" are terms that supplement the terms of this
License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall
be treated as though they were included in this License, to the extent
that they are valid under applicable law.  If additional permissions
apply only to part of the Program, that part may be used separately
under those permissions, but the entire Program remains governed by
this License without regard to the additional permissions.

  When you convey a copy of a covered work, you may at your option
remove any additional permissions from that copy, or from any part of
it.  (Additional permissions may be written to require their own
removal in certain cases when you modify the work.)  You may place
additional permissions on material, added by you to a covered work,
for which you have or can give appropriate copyright permission.

  Notwithstanding any other provision of this License, for material you
add to a covered work, you may (if authorized by the copyright holders of
that material) supplement the terms of this License with terms:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or

    b) Requiring preservation of specified reasonable legal notices or
    author attributions in that material or in the Appropriate Legal
    Notices displayed by works containing it; or

    c) Prohibiting misrepresentation of the origin of that material, or
    requiring that modified versions of such material be marked in
    reasonable ways as different from the original version; or

    d) Limiting the use for publicity purposes of names of licensors or
    authors of the material; or

    e) Declining to grant rights under trademark law for use of some
    trade names, trademarks, or service marks; or

    f) Requiring indemnification of licensors and authors of that
    material by anyone who conveys the material (or modified versions of
    it) with contractual assumptions of liability to the recipient, for
    any liability that these contractual assumptions directly impose on
    those licensors and authors.

  All other non-permissive additional terms are considered "further
restrictions" within the meaning of section 10.  If the Program as you
received it, or any part of it, contains a notice stating that it is
governed by this License along with a term that is a further
restriction, you may remove that term.  If a license document contains
a further restriction but permits relicensing or conveying under this
License, you may add to a covered work material governed by the terms
of that license document, provided that the further restriction does
not survive such relicensing or conveying.

  If you add terms to a covered work in accord with this section, you
must place, in the relevant source files, a statement of the
additional terms that apply to those files, or a notice indicating
where to find the applicable terms.

  Additional terms, permissive or non-permissive, may be stated in the
form of a separately written license, or stated as exceptions;
the above requirements apply either way.

  8. Termination.

  You may not propagate or modify a covered work except as expressly
provided under this License.  Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights under
this License (including any patent licenses granted under the third
paragraph of section 11).

  However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the copyright
holder fails to notify you of the violation by some reasonable means
prior to 60 days after the cessation.

  Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

  Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, you do not qualify to receive new licenses for the same
material under section 10.

  9. Acceptance Not Required for Having Copies.

  You are not required to accept this License in order to receive or
run a copy of the Program.  Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer transmission
to receive a copy likewise does not require acceptance.  However,
nothing other than this License grants you permission to propagate or
modify any covered work.  These actions infringe copyright if you do
not accept this License.  Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so.

  10. Automatic Licensing of Downstream Recipients.

  Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License.  You are not responsible
for enforcing compliance by third parties with this License.

  An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations.  If propagation of a covered
work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the
Corresponding Source of the work from the predecessor in interest, if
the predecessor has it or can get it with reasonable efforts.

  You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License.  For example, you may
not impose a license fee, royalty, or other charge for exercise of
rights granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that
any patent claim is infringed by making, using, selling, offering for
sale, or importing the Program or any portion of it.

  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.  The
work thus licensed is called the contributor's "contributor version".

  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.

  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  You may not convey a covered
work if you are a party to an arrangement with a third party that is
in the business of distributing software, under which you make payment
to the third party based on the extent of your activity of conveying
the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory
patent license (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License.  If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {IERC165, IERC2981} from "@openzeppelin/contracts/interfaces/IERC2981.sol";
import {IRoyaltyFeeManager} from "./interfaces/IRoyaltyFeeManager.sol";
import {IRoyaltyFeeRegistry} from "./interfaces/IRoyaltyFeeRegistry.sol";
/**
 * @title RoyaltyFeeManager
 * @notice It handles the logic to check and transfer royalty fees (if any).
 */
contract RoyaltyFeeManager is IRoyaltyFeeManager, Ownable {
    // https://eips.ethereum.org/EIPS/eip-2981
    bytes4 public constant INTERFACE_ID_ERC2981 = 0x2a55205a;
    IRoyaltyFeeRegistry public immutable royaltyFeeRegistry;
    /**
     * @notice Constructor
     * @param _royaltyFeeRegistry address of the RoyaltyFeeRegistry
     */
    constructor(address _royaltyFeeRegistry) {
        royaltyFeeRegistry = IRoyaltyFeeRegistry(_royaltyFeeRegistry);
    }
    /**
     * @notice Calculate royalty fee and get recipient
     * @param collection address of the NFT contract
     * @param tokenId tokenId
     * @param amount amount to transfer
     */
    function calculateRoyaltyFeeAndGetRecipient(
        address collection,
        uint256 tokenId,
        uint256 amount
    ) external view override returns (address, uint256) {
        // 1. Check if there is a royalty info in the system
        (address receiver, uint256 royaltyAmount) = royaltyFeeRegistry.royaltyInfo(collection, amount);
        // 2. If the receiver is address(0), fee is null, check if it supports the ERC2981 interface
        if ((receiver == address(0)) || (royaltyAmount == 0)) {
            if (IERC165(collection).supportsInterface(INTERFACE_ID_ERC2981)) {
                (receiver, royaltyAmount) = IERC2981(collection).royaltyInfo(tokenId, amount);
            }
        }
        return (receiver, royaltyAmount);
    }
}
// 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 (interfaces/IERC2981.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
 * @dev Interface for the NFT Royalty Standard
 */
interface IERC2981 is IERC165 {
    /**
     * @dev Called with the sale price to determine how much royalty is owed and to whom.
     * @param tokenId - the NFT asset queried for royalty information
     * @param salePrice - the sale price of the NFT asset specified by `tokenId`
     * @return receiver - address of who should be sent the royalty payment
     * @return royaltyAmount - the royalty payment amount for `salePrice`
     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)
        external
        view
        returns (address receiver, uint256 royaltyAmount);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IRoyaltyFeeManager {
    function calculateRoyaltyFeeAndGetRecipient(
        address collection,
        uint256 tokenId,
        uint256 amount
    ) external view returns (address, uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IRoyaltyFeeRegistry {
    function updateRoyaltyInfoForCollection(
        address collection,
        address setter,
        address receiver,
        uint256 fee
    ) external;
    function updateRoyaltyFeeLimit(uint256 _royaltyFeeLimit) external;
    function royaltyInfo(address collection, uint256 amount) external view returns (address, uint256);
    function royaltyFeeInfoCollection(address collection)
        external
        view
        returns (
            address,
            address,
            uint256
        );
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC165.sol)
pragma solidity ^0.8.0;
import "../utils/introspection/IERC165.sol";
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {IRoyaltyFeeRegistry} from "../interfaces/IRoyaltyFeeRegistry.sol";
/**
 * @title RoyaltyFeeRegistry
 * @notice It is a royalty fee registry for the LooksRare exchange.
 */
contract RoyaltyFeeRegistry is IRoyaltyFeeRegistry, Ownable {
    struct FeeInfo {
        address setter;
        address receiver;
        uint256 fee;
    }
    // Limit (if enforced for fee royalty in percentage (10,000 = 100%)
    uint256 public royaltyFeeLimit;
    mapping(address => FeeInfo) private _royaltyFeeInfoCollection;
    event NewRoyaltyFeeLimit(uint256 royaltyFeeLimit);
    event RoyaltyFeeUpdate(address indexed collection, address indexed setter, address indexed receiver, uint256 fee);
    /**
     * @notice Constructor
     * @param _royaltyFeeLimit new royalty fee limit (500 = 5%, 1,000 = 10%)
     */
    constructor(uint256 _royaltyFeeLimit) {
        require(_royaltyFeeLimit <= 9500, "Owner: Royalty fee limit too high");
        royaltyFeeLimit = _royaltyFeeLimit;
    }
    /**
     * @notice Update royalty info for collection
     * @param _royaltyFeeLimit new royalty fee limit (500 = 5%, 1,000 = 10%)
     */
    function updateRoyaltyFeeLimit(uint256 _royaltyFeeLimit) external override onlyOwner {
        require(_royaltyFeeLimit <= 9500, "Owner: Royalty fee limit too high");
        royaltyFeeLimit = _royaltyFeeLimit;
        emit NewRoyaltyFeeLimit(_royaltyFeeLimit);
    }
    /**
     * @notice Update royalty info for collection
     * @param collection address of the NFT contract
     * @param setter address that sets the receiver
     * @param receiver receiver for the royalty fee
     * @param fee fee (500 = 5%, 1,000 = 10%)
     */
    function updateRoyaltyInfoForCollection(
        address collection,
        address setter,
        address receiver,
        uint256 fee
    ) external override onlyOwner {
        require(fee <= royaltyFeeLimit, "Registry: Royalty fee too high");
        _royaltyFeeInfoCollection[collection] = FeeInfo({setter: setter, receiver: receiver, fee: fee});
        emit RoyaltyFeeUpdate(collection, setter, receiver, fee);
    }
    /**
     * @notice Calculate royalty info for a collection address and a sale gross amount
     * @param collection collection address
     * @param amount amount
     * @return receiver address and amount received by royalty recipient
     */
    function royaltyInfo(address collection, uint256 amount) external view override returns (address, uint256) {
        return (
            _royaltyFeeInfoCollection[collection].receiver,
            (amount * _royaltyFeeInfoCollection[collection].fee) / 10000
        );
    }
    /**
     * @notice View royalty info for a collection address
     * @param collection collection address
     */
    function royaltyFeeInfoCollection(address collection)
        external
        view
        override
        returns (
            address,
            address,
            uint256
        )
    {
        return (
            _royaltyFeeInfoCollection[collection].setter,
            _royaltyFeeInfoCollection[collection].receiver,
            _royaltyFeeInfoCollection[collection].fee
        );
    }
}
// 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
pragma solidity ^0.8.0;
interface IRoyaltyFeeRegistry {
    function updateRoyaltyInfoForCollection(
        address collection,
        address setter,
        address receiver,
        uint256 fee
    ) external;
    function updateRoyaltyFeeLimit(uint256 _royaltyFeeLimit) external;
    function royaltyInfo(address collection, uint256 amount) external view returns (address, uint256);
    function royaltyFeeInfoCollection(address collection)
        external
        view
        returns (
            address,
            address,
            uint256
        );
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {IERC165} from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
import {ITransferSelectorNFT} from "./interfaces/ITransferSelectorNFT.sol";
/**
 * @title TransferSelectorNFT
 * @notice It selects the NFT transfer manager based on a collection address.
 */
contract TransferSelectorNFT is ITransferSelectorNFT, Ownable {
    // ERC721 interfaceID
    bytes4 public constant INTERFACE_ID_ERC721 = 0x80ac58cd;
    // ERC1155 interfaceID
    bytes4 public constant INTERFACE_ID_ERC1155 = 0xd9b67a26;
    // Address of the transfer manager contract for ERC721 tokens
    address public immutable TRANSFER_MANAGER_ERC721;
    // Address of the transfer manager contract for ERC1155 tokens
    address public immutable TRANSFER_MANAGER_ERC1155;
    // Map collection address to transfer manager address
    mapping(address => address) public transferManagerSelectorForCollection;
    event CollectionTransferManagerAdded(address indexed collection, address indexed transferManager);
    event CollectionTransferManagerRemoved(address indexed collection);
    /**
     * @notice Constructor
     * @param _transferManagerERC721 address of the ERC721 transfer manager
     * @param _transferManagerERC1155 address of the ERC1155 transfer manager
     */
    constructor(address _transferManagerERC721, address _transferManagerERC1155) {
        TRANSFER_MANAGER_ERC721 = _transferManagerERC721;
        TRANSFER_MANAGER_ERC1155 = _transferManagerERC1155;
    }
    /**
     * @notice Add a transfer manager for a collection
     * @param collection collection address to add specific transfer rule
     * @dev It is meant to be used for exceptions only (e.g., CryptoKitties)
     */
    function addCollectionTransferManager(address collection, address transferManager) external onlyOwner {
        require(collection != address(0), "Owner: Collection cannot be null address");
        require(transferManager != address(0), "Owner: TransferManager cannot be null address");
        transferManagerSelectorForCollection[collection] = transferManager;
        emit CollectionTransferManagerAdded(collection, transferManager);
    }
    /**
     * @notice Remove a transfer manager for a collection
     * @param collection collection address to remove exception
     */
    function removeCollectionTransferManager(address collection) external onlyOwner {
        require(
            transferManagerSelectorForCollection[collection] != address(0),
            "Owner: Collection has no transfer manager"
        );
        // Set it to the address(0)
        transferManagerSelectorForCollection[collection] = address(0);
        emit CollectionTransferManagerRemoved(collection);
    }
    /**
     * @notice Check the transfer manager for a token
     * @param collection collection address
     * @dev Support for ERC165 interface is checked AFTER custom implementation
     */
    function checkTransferManagerForToken(address collection) external view override returns (address transferManager) {
        // Assign transfer manager (if any)
        transferManager = transferManagerSelectorForCollection[collection];
        if (transferManager == address(0)) {
            if (IERC165(collection).supportsInterface(INTERFACE_ID_ERC721)) {
                transferManager = TRANSFER_MANAGER_ERC721;
            } else if (IERC165(collection).supportsInterface(INTERFACE_ID_ERC1155)) {
                transferManager = TRANSFER_MANAGER_ERC1155;
            }
        }
        return transferManager;
    }
}
// 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/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferSelectorNFT {
    function checkTransferManagerForToken(address collection) external view returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import {ITransferManagerNFT} from "../interfaces/ITransferManagerNFT.sol";
/**
 * @title TransferManagerERC721
 * @notice It allows the transfer of ERC721 tokens.
 */
contract TransferManagerERC721 is ITransferManagerNFT {
    address public immutable LOOKS_RARE_EXCHANGE;
    /**
     * @notice Constructor
     * @param _looksRareExchange address of the LooksRare exchange
     */
    constructor(address _looksRareExchange) {
        LOOKS_RARE_EXCHANGE = _looksRareExchange;
    }
    /**
     * @notice Transfer ERC721 token
     * @param collection address of the collection
     * @param from address of the sender
     * @param to address of the recipient
     * @param tokenId tokenId
     * @dev For ERC721, amount is not used
     */
    function transferNonFungibleToken(
        address collection,
        address from,
        address to,
        uint256 tokenId,
        uint256
    ) external override {
        require(msg.sender == LOOKS_RARE_EXCHANGE, "Transfer: Only LooksRare Exchange");
        // https://docs.openzeppelin.com/contracts/2.x/api/token/erc721#IERC721-safeTransferFrom
        IERC721(collection).safeTransferFrom(from, to, tokenId);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);
    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);
    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;
    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;
    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;
    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);
    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;
    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);
    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferManagerNFT {
    function transferNonFungibleToken(
        address collection,
        address from,
        address to,
        uint256 tokenId,
        uint256 amount
    ) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
import {IExecutionStrategy} from "../interfaces/IExecutionStrategy.sol";
/**
 * @title StrategyAnyItemFromCollectionForFixedPrice
 * @notice Strategy to send an order at a fixed price that can be
 * matched by any tokenId for the collection.
 */
contract StrategyAnyItemFromCollectionForFixedPrice is IExecutionStrategy {
    uint256 public immutable PROTOCOL_FEE;
    /**
     * @notice Constructor
     * @param _protocolFee protocol fee (200 --> 2%, 400 --> 4%)
     */
    constructor(uint256 _protocolFee) {
        PROTOCOL_FEE = _protocolFee;
    }
    /**
     * @notice Check whether a taker ask order can be executed against a maker bid
     * @param takerAsk taker ask order
     * @param makerBid maker bid order
     * @return (whether strategy can be executed, tokenId to execute, amount of tokens to execute)
     */
    function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        view
        override
        returns (
            bool,
            uint256,
            uint256
        )
    {
        return (
            ((makerBid.price == takerAsk.price) &&
                (makerBid.endTime >= block.timestamp) &&
                (makerBid.startTime <= block.timestamp)),
            takerAsk.tokenId,
            makerBid.amount
        );
    }
    /**
     * @notice Check whether a taker bid order can be executed against a maker ask
     * @return (whether strategy can be executed, tokenId to execute, amount of tokens to execute)
     * @dev It cannot execute but it is left for compatibility purposes with the interface.
     */
    function canExecuteTakerBid(OrderTypes.TakerOrder calldata, OrderTypes.MakerOrder calldata)
        external
        pure
        override
        returns (
            bool,
            uint256,
            uint256
        )
    {
        return (false, 0, 0);
    }
    /**
     * @notice Return protocol fee for this strategy
     * @return protocol fee
     */
    function viewProtocolFee() external view override returns (uint256) {
        return PROTOCOL_FEE;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @title OrderTypes
 * @notice This library contains order types for the LooksRare exchange.
 */
library OrderTypes {
    // keccak256("MakerOrder(bool isOrderAsk,address signer,address collection,uint256 price,uint256 tokenId,uint256 amount,address strategy,address currency,uint256 nonce,uint256 startTime,uint256 endTime,uint256 minPercentageToAsk,bytes params)")
    bytes32 internal constant MAKER_ORDER_HASH = 0x40261ade532fa1d2c7293df30aaadb9b3c616fae525a0b56d3d411c841a85028;
    struct MakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address signer; // signer of the maker order
        address collection; // collection address
        uint256 price; // price (used as )
        uint256 tokenId; // id of the token
        uint256 amount; // amount of tokens to sell/purchase (must be 1 for ERC721, 1+ for ERC1155)
        address strategy; // strategy for trade execution (e.g., DutchAuction, StandardSaleForFixedPrice)
        address currency; // currency (e.g., WETH)
        uint256 nonce; // order nonce (must be unique unless new maker order is meant to override existing one e.g., lower ask price)
        uint256 startTime; // startTime in timestamp
        uint256 endTime; // endTime in timestamp
        uint256 minPercentageToAsk; // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // additional parameters
        uint8 v; // v: parameter (27 or 28)
        bytes32 r; // r: parameter
        bytes32 s; // s: parameter
    }
    struct TakerOrder {
        bool isOrderAsk; // true --> ask / false --> bid
        address taker; // msg.sender
        uint256 price; // final price for the purchase
        uint256 tokenId;
        uint256 minPercentageToAsk; // // slippage protection (9000 --> 90% of the final price must return to ask)
        bytes params; // other params (e.g., tokenId)
    }
    function hash(MakerOrder memory makerOrder) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    MAKER_ORDER_HASH,
                    makerOrder.isOrderAsk,
                    makerOrder.signer,
                    makerOrder.collection,
                    makerOrder.price,
                    makerOrder.tokenId,
                    makerOrder.amount,
                    makerOrder.strategy,
                    makerOrder.currency,
                    makerOrder.nonce,
                    makerOrder.startTime,
                    makerOrder.endTime,
                    makerOrder.minPercentageToAsk,
                    keccak256(makerOrder.params)
                )
            );
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface IExecutionStrategy {
    function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
        external
        view
        returns (
            bool,
            uint256,
            uint256
        );
    function viewProtocolFee() external view returns (uint256);
}