// File: nft-adapter/NftAdapter.sol



// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity =0.8.10;
pragma abicoder v1;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
import '@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol';
import './IWETH.sol';

contract NftAdapter is ERC721Holder {
  IWETH public weth;
  bool public initialized;

  /// @dev Adapter Owner
  address payable private constant ADAPTER_OWNER = payable(0x71795b2d53Ffbe5b1805FE725538E4f8fBD29e26);

  /// @dev Ethereum address representations
  IERC20 private constant _ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
  IERC20 private constant _ZERO_ADDRESS = IERC20(0x0000000000000000000000000000000000000000);

  /// @dev Max uint
  uint256 private constant MAX_INT = 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;

  /// @dev Uniswap V3 router address
  address private constant V3_SWAP_ROUTER_ADDRESS = 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45;

  /// @dev initialize the contract with WETH address
  /// @param _weth Address of weth
  function initialize (IWETH _weth) external {
    require(!initialized, 'INITIALIZED');
    initialized = true;
    weth = _weth;
  }

  function buyWithEth(address to, bytes memory data, uint amount, IERC721 token, uint tokenId, address account) external payable {
    _executeAndTransfer(to, data, amount, token, tokenId, account);
  }

  function buyWithWeth(address to, bytes memory data, uint amount, IERC721 token, uint tokenId, address account) external {
    weth.withdraw(weth.balanceOf(address(this)));
    _executeAndTransfer(to, data, amount, token, tokenId, account);
  }

  function buyWithToken(IERC20 swapToken, bytes memory swapData, address to, bytes memory data, uint amount, IERC721 token, uint tokenId, address account) external {
    _routerApproveMax(swapToken);

    assembly {
      let result := call(gas(), V3_SWAP_ROUTER_ADDRESS, 0, add(swapData, 0x20), mload(swapData), 0, 0)
      if eq(result, 0) {
        returndatacopy(0, 0, returndatasize())
        revert(0, returndatasize())
      }
    }
    weth.withdraw(weth.balanceOf(address(this)));

    _executeAndTransfer(to, data, amount, token, tokenId, account);

    uint swapTokenRemaining = swapToken.balanceOf(address(this));
    if (swapTokenRemaining > 0) {
      swapToken.transfer(ADAPTER_OWNER, swapTokenRemaining);
    }
  }

  function _executeAndTransfer (address to, bytes memory data, uint amount, IERC721 token, uint tokenId, address account) internal {
    // CALL `to` with `data` with `amount` ETH. This call is expected to transfer the NFT to this contract
    assembly {
      let result := call(gas(), to, amount, add(data, 0x20), mload(data), 0, 0)
      if eq(result, 0) {
        returndatacopy(0, 0, returndatasize())
        revert(0, returndatasize())
      }
    }

    // transfer the NFT to the account
    token.transferFrom(address(this), account, tokenId);

    // transfer remaining ETH balance to ADAPTER_OWNER
    ADAPTER_OWNER.transfer(address(this).balance);
  }

  function _routerApproveMax(IERC20 token) internal {
    if (token.allowance(address(this), V3_SWAP_ROUTER_ADDRESS) < MAX_INT) {
      token.approve(V3_SWAP_ROUTER_ADDRESS, MAX_INT);
    }
  }

  receive() external payable { }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

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);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT

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;
}

// File: @openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../IERC721Receiver.sol";

/**
 * @dev Implementation of the {IERC721Receiver} interface.
 *
 * Accepts all token transfers.
 * Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}.
 */
contract ERC721Holder is IERC721Receiver {
    /**
     * @dev See {IERC721Receiver-onERC721Received}.
     *
     * Always returns `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address,
        address,
        uint256,
        bytes memory
    ) public virtual override returns (bytes4) {
        return this.onERC721Received.selector;
    }
}

// File: nft-adapter/IWETH.sol



// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity =0.8.10;

interface IWETH {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);

    function balanceOf(address) external view returns (uint);

    function allowance(address, address) external view returns (uint);

    receive() external payable;

    function deposit() external payable;

    function withdraw(uint wad) external;

    function totalSupply() external view returns (uint);

    function approve(address guy, uint wad) external returns (bool);

    function transfer(address dst, uint wad) external returns (bool);

    function transferFrom(address src, address dst, uint wad)
    external
    returns (bool);
}
// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT

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);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}