@levxdao/airdrop/deployments/mainnet/solcInputs/3e8fef43ca6da9b9316505ffcb4b9dd0.json

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{
  "language": "Solidity",
  "sources": {
    "contracts/ERC20Airdrops.sol": {
      "content": "// SPDX-License-Identifier: UNLICENSED\n\npragma solidity =0.8.3;\n\nimport \"@openzeppelin/contracts/token/ERC20/IERC20.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol\";\nimport \"./MerkleProof.sol\";\n\ncontract ERC20Airdrops is MerkleProof {\n    using SafeERC20 for IERC20;\n\n    mapping(address => mapping(bytes32 => uint256)) public deadlineOf;\n    mapping(address => mapping(bytes32 => address)) public walletOf;\n    mapping(address => mapping(bytes32 => mapping(bytes32 => bool))) internal _hasClaimed;\n\n    event AddMerkleRoot(address indexed token, bytes32 indexed merkleRoot, address wallet, uint256 deadline);\n    event Claim(\n        address indexed token,\n        bytes32 indexed merkleRoot,\n        address wallet,\n        address indexed account,\n        uint256 amount\n    );\n\n    function addMerkleRoot(\n        address token,\n        bytes32 merkleRoot,\n        uint256 deadline\n    ) external {\n        address wallet = walletOf[token][merkleRoot];\n        require(wallet == address(0), \"LEVX: DUPLICATE_ROOT\");\n        walletOf[token][merkleRoot] = msg.sender;\n        deadlineOf[token][merkleRoot] = deadline;\n\n        emit AddMerkleRoot(token, merkleRoot, msg.sender, deadline);\n    }\n\n    function claim(\n        address token,\n        bytes32 merkleRoot,\n        bytes32[] calldata merkleProof,\n        uint256 amount\n    ) external {\n        address wallet = walletOf[token][merkleRoot];\n        require(wallet != address(0), \"LEVX: INVALID_ROOT\");\n        require(block.timestamp < deadlineOf[token][merkleRoot], \"LEVX: EXPIRED\");\n\n        bytes32 leaf = keccak256(abi.encodePacked(msg.sender, amount));\n        require(!_hasClaimed[token][merkleRoot][leaf], \"LEVX: FORBIDDEN\");\n        require(verify(merkleRoot, leaf, merkleProof), \"LEVX: INVALID_PROOF\");\n\n        _hasClaimed[token][merkleRoot][leaf] = true;\n        IERC20(token).safeTransferFrom(wallet, msg.sender, amount);\n\n        emit Claim(token, merkleRoot, wallet, msg.sender, amount);\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC20/IERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller's account to `to`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address to, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender's allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `from` to `to` using the\n     * allowance mechanism. `amount` is then deducted from the caller's\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 amount\n    ) external returns (bool);\n\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC20.sol\";\nimport \"../../../utils/Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using Address for address;\n\n    function safeTransfer(\n        IERC20 token,\n        address to,\n        uint256 value\n    ) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(\n        IERC20 token,\n        address from,\n        address to,\n        uint256 value\n    ) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'\n        require(\n            (value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        uint256 newAllowance = token.allowance(address(this), spender) + value;\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        unchecked {\n            uint256 oldAllowance = token.allowance(address(this), spender);\n            require(oldAllowance >= value, \"SafeERC20: decreased allowance below zero\");\n            uint256 newAllowance = oldAllowance - value;\n            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n        }\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since\n        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length > 0) {\n            // Return data is optional\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n"
    },
    "contracts/MerkleProof.sol": {
      "content": "// SPDX-License-Identifier: UNLICENSED\n\npragma solidity =0.8.3;\n\ncontract MerkleProof {\n    function verify(\n        bytes32 root,\n        bytes32 leaf,\n        bytes32[] memory proof\n    ) public pure returns (bool) {\n        bytes32 computedHash = leaf;\n\n        for (uint256 i = 0; i < proof.length; i++) {\n            bytes32 proofElement = proof[i];\n\n            if (computedHash < proofElement) {\n                // Hash(current computed hash + current element of the proof)\n                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));\n            } else {\n                // Hash(current element of the proof + current computed hash)\n                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));\n            }\n        }\n\n        // Check if the computed hash (root) is equal to the provided root\n        return computedHash == root;\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Address.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)\n\npragma solidity ^0.8.1;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     *\n     * [IMPORTANT]\n     * ====\n     * You shouldn't rely on `isContract` to protect against flash loan attacks!\n     *\n     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets\n     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract\n     * constructor.\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize/address.code.length, which returns 0\n        // for contracts in construction, since the code is only stored at the end\n        // of the constructor execution.\n\n        return account.code.length > 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n        (bool success, ) = recipient.call{value: amount}(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain `call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        require(address(this).balance >= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.call{value: value}(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the\n     * revert reason using the provided one.\n     *\n     * _Available since v4.3._\n     */\n    function verifyCallResult(\n        bool success,\n        bytes memory returndata,\n        string memory errorMessage\n    ) internal pure returns (bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length > 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n"
    },
    "contracts/LevxAirdrop.sol": {
      "content": "// SPDX-License-Identifier: UNLICENSED\n\npragma solidity =0.8.3;\n\nimport \"@openzeppelin/contracts/access/Ownable.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/IERC20.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol\";\nimport \"./MerkleProof.sol\";\n\ncontract LevxAirdrop is Ownable, MerkleProof {\n    using SafeERC20 for IERC20;\n\n    address public immutable levx;\n    mapping(bytes32 => bool) public isValidMerkleRoot;\n    mapping(bytes32 => mapping(bytes32 => bool)) internal _hasClaimed;\n\n    event AddMerkleRoot(bytes32 indexed merkleRoot);\n    event Claim(bytes32 indexed merkleRoot, address indexed account, uint256 amount);\n\n    constructor(address _owner, address _levx) {\n        levx = _levx;\n        _transferOwnership(_owner);\n    }\n\n    function addMerkleRoot(bytes32 merkleRoot) external onlyOwner {\n        require(!isValidMerkleRoot[merkleRoot], \"SHOYU: DUPLICATE_ROOT\");\n        isValidMerkleRoot[merkleRoot] = true;\n\n        emit AddMerkleRoot(merkleRoot);\n    }\n\n    function claim(\n        bytes32 merkleRoot,\n        bytes32[] calldata merkleProof,\n        uint256 amount\n    ) external {\n        require(isValidMerkleRoot[merkleRoot], \"SHOYU: INVALID_ROOT\");\n\n        bytes32 leaf = keccak256(abi.encodePacked(msg.sender, amount));\n        require(!_hasClaimed[merkleRoot][leaf], \"SHOYU: FORBIDDEN\");\n        require(verify(merkleRoot, leaf, merkleProof), \"SHOYU: INVALID_PROOF\");\n\n        _hasClaimed[merkleRoot][leaf] = true;\n        IERC20(levx).safeTransferFrom(owner(), msg.sender, amount);\n\n        emit Claim(merkleRoot, msg.sender, amount);\n    }\n}\n"
    },
    "@openzeppelin/contracts/access/Ownable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../utils/Context.sol\";\n\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * By default, the owner account will be the one that deploys the contract. This\n * can later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n    address private _owner;\n\n    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n    /**\n     * @dev Initializes the contract setting the deployer as the initial owner.\n     */\n    constructor() {\n        _transferOwnership(_msgSender());\n    }\n\n    /**\n     * @dev Returns the address of the current owner.\n     */\n    function owner() public view virtual returns (address) {\n        return _owner;\n    }\n\n    /**\n     * @dev Throws if called by any account other than the owner.\n     */\n    modifier onlyOwner() {\n        require(owner() == _msgSender(), \"Ownable: caller is not the owner\");\n        _;\n    }\n\n    /**\n     * @dev Leaves the contract without owner. It will not be possible to call\n     * `onlyOwner` functions anymore. Can only be called by the current owner.\n     *\n     * NOTE: Renouncing ownership will leave the contract without an owner,\n     * thereby removing any functionality that is only available to the owner.\n     */\n    function renounceOwnership() public virtual onlyOwner {\n        _transferOwnership(address(0));\n    }\n\n    /**\n     * @dev Transfers ownership of the contract to a new account (`newOwner`).\n     * Can only be called by the current owner.\n     */\n    function transferOwnership(address newOwner) public virtual onlyOwner {\n        require(newOwner != address(0), \"Ownable: new owner is the zero address\");\n        _transferOwnership(newOwner);\n    }\n\n    /**\n     * @dev Transfers ownership of the contract to a new account (`newOwner`).\n     * Internal function without access restriction.\n     */\n    function _transferOwnership(address newOwner) internal virtual {\n        address oldOwner = _owner;\n        _owner = newOwner;\n        emit OwnershipTransferred(oldOwner, newOwner);\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Context.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes calldata) {\n        return msg.data;\n    }\n}\n"
    },
    "contracts/NFTAirdropsAndSales.sol": {
      "content": "// SPDX-License-Identifier: UNLICENSED\n\npragma solidity =0.8.3;\n\nimport \"@openzeppelin/contracts/access/Ownable.sol\";\nimport \"@openzeppelin/contracts/utils/cryptography/ECDSA.sol\";\nimport \"@shoyunft/contracts/contracts/interfaces/INFT721.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/IERC20.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol\";\n\ncontract NFTAirdropsAndSales is Ownable {\n    using SafeERC20 for IERC20;\n\n    address public immutable nftContract;\n    address public immutable levx;\n    address public immutable wallet;\n    mapping(bytes32 => Airdrop) public airdrops;\n    mapping(address => bool) public isMinter;\n    mapping(bytes32 => mapping(bytes32 => bool)) internal _minted;\n\n    struct Airdrop {\n        address signer;\n        uint64 deadline;\n        uint256 nextTokenId;\n        uint256 maxTokenId;\n    }\n\n    event SetMinter(address account, bool indexed isMinter);\n    event Add(bytes32 indexed slug, address signer, uint64 deadline, uint256 fromTokenId, uint256 maxTokenId);\n    event Claim(bytes32 indexed slug, bytes32 indexed id, address indexed to, uint256 tokenId, uint256 price);\n\n    constructor(\n        address _nftContract,\n        address _levx,\n        address _wallet\n    ) {\n        nftContract = _nftContract;\n        levx = _levx;\n        wallet = _wallet;\n    }\n\n    function setMinter(address account, bool _isMinter) external onlyOwner {\n        isMinter[account] = _isMinter;\n\n        emit SetMinter(account, _isMinter);\n    }\n\n    function transferOwnershipOfNFTContract(address newOwner) external onlyOwner {\n        INFT721(nftContract).transferOwnership(newOwner);\n    }\n\n    function setRoyaltyFeeRecipient(address _royaltyFeeRecipient) external onlyOwner {\n        INFT721(nftContract).setRoyaltyFeeRecipient(_royaltyFeeRecipient);\n    }\n\n    function setRoyaltyFee(uint8 _royaltyFee) external onlyOwner {\n        INFT721(nftContract).setRoyaltyFee(_royaltyFee);\n    }\n\n    function setTokenURI(uint256 tokenId, string memory uri) external onlyOwner {\n        INFT721(nftContract).setTokenURI(tokenId, uri);\n    }\n\n    function setBaseURI(string memory baseURI) external onlyOwner {\n        INFT721(nftContract).setBaseURI(baseURI);\n    }\n\n    function parkTokenIds(uint256 toTokenId) external onlyOwner {\n        INFT721(nftContract).parkTokenIds(toTokenId);\n    }\n\n    function mint(\n        address to,\n        uint256 tokenId,\n        bytes calldata data\n    ) external {\n        require(msg.sender == owner() || isMinter[msg.sender], \"LEVX: FORBIDDEN\");\n\n        INFT721(nftContract).mint(to, tokenId, data);\n    }\n\n    function mintBatch(\n        address to,\n        uint256[] calldata tokenIds,\n        bytes calldata data\n    ) external {\n        require(msg.sender == owner() || isMinter[msg.sender], \"LEVX: FORBIDDEN\");\n\n        INFT721(nftContract).mintBatch(to, tokenIds, data);\n    }\n\n    function add(\n        bytes32 slug,\n        address signer,\n        uint64 deadline,\n        uint256 fromTokenId,\n        uint256 maxTokenId\n    ) external onlyOwner {\n        Airdrop storage airdrop = airdrops[slug];\n        require(airdrop.signer == address(0), \"LEVX: ADDED\");\n\n        airdrop.signer = signer;\n        airdrop.deadline = deadline;\n        airdrop.nextTokenId = fromTokenId;\n        airdrop.maxTokenId = maxTokenId;\n\n        emit Add(slug, signer, deadline, fromTokenId, maxTokenId);\n    }\n\n    function claim(\n        bytes32 slug,\n        bytes32 id,\n        uint256 tokenId,\n        uint256 price,\n        uint8 v,\n        bytes32 r,\n        bytes32 s,\n        address to,\n        bytes calldata data\n    ) external {\n        Airdrop storage airdrop = airdrops[slug];\n        {\n            (address signer, uint64 deadline) = (airdrop.signer, airdrop.deadline);\n\n            require(signer != address(0), \"LEVX: INVALID_SLUG\");\n            require(deadline == 0 || uint64(block.timestamp) < deadline, \"LEVX: EXPIRED\");\n            require(!_minted[slug][id], \"LEVX: MINTED\");\n\n            bytes32 message = keccak256(abi.encodePacked(slug, id, tokenId, price));\n            require(ECDSA.recover(ECDSA.toEthSignedMessageHash(message), v, r, s) == signer, \"LEVX: UNAUTHORIZED\");\n        }\n\n        {\n            (uint256 nextTokenId, uint256 maxTokenId) = (airdrop.nextTokenId, airdrop.maxTokenId);\n\n            if (tokenId == 0) {\n                tokenId = nextTokenId;\n                while (tokenId < maxTokenId) {\n                    if (INFT721(nftContract).ownerOf(tokenId) == address(0)) {\n                        break;\n                    }\n                    tokenId++;\n                }\n                require(tokenId < maxTokenId, \"LEVX: INVALID_TOKEN_ID\");\n                airdrop.nextTokenId = tokenId + 1;\n            } else {\n                require(tokenId >= nextTokenId && tokenId < maxTokenId, \"LEVX: INVALID_TOKEN_ID\");\n            }\n        }\n\n        _minted[slug][id] = true;\n\n        emit Claim(slug, id, to, tokenId, price);\n        if (price > 0) IERC20(levx).safeTransferFrom(msg.sender, wallet, price);\n        INFT721(nftContract).mint(to, tokenId, data);\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/cryptography/ECDSA.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../Strings.sol\";\n\n/**\n * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.\n *\n * These functions can be used to verify that a message was signed by the holder\n * of the private keys of a given address.\n */\nlibrary ECDSA {\n    enum RecoverError {\n        NoError,\n        InvalidSignature,\n        InvalidSignatureLength,\n        InvalidSignatureS,\n        InvalidSignatureV\n    }\n\n    function _throwError(RecoverError error) private pure {\n        if (error == RecoverError.NoError) {\n            return; // no error: do nothing\n        } else if (error == RecoverError.InvalidSignature) {\n            revert(\"ECDSA: invalid signature\");\n        } else if (error == RecoverError.InvalidSignatureLength) {\n            revert(\"ECDSA: invalid signature length\");\n        } else if (error == RecoverError.InvalidSignatureS) {\n            revert(\"ECDSA: invalid signature 's' value\");\n        } else if (error == RecoverError.InvalidSignatureV) {\n            revert(\"ECDSA: invalid signature 'v' value\");\n        }\n    }\n\n    /**\n     * @dev Returns the address that signed a hashed message (`hash`) with\n     * `signature` or error string. This address can then be used for verification purposes.\n     *\n     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:\n     * this function rejects them by requiring the `s` value to be in the lower\n     * half order, and the `v` value to be either 27 or 28.\n     *\n     * IMPORTANT: `hash` _must_ be the result of a hash operation for the\n     * verification to be secure: it is possible to craft signatures that\n     * recover to arbitrary addresses for non-hashed data. A safe way to ensure\n     * this is by receiving a hash of the original message (which may otherwise\n     * be too long), and then calling {toEthSignedMessageHash} on it.\n     *\n     * Documentation for signature generation:\n     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]\n     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]\n     *\n     * _Available since v4.3._\n     */\n    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {\n        // Check the signature length\n        // - case 65: r,s,v signature (standard)\n        // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._\n        if (signature.length == 65) {\n            bytes32 r;\n            bytes32 s;\n            uint8 v;\n            // ecrecover takes the signature parameters, and the only way to get them\n            // currently is to use assembly.\n            assembly {\n                r := mload(add(signature, 0x20))\n                s := mload(add(signature, 0x40))\n                v := byte(0, mload(add(signature, 0x60)))\n            }\n            return tryRecover(hash, v, r, s);\n        } else if (signature.length == 64) {\n            bytes32 r;\n            bytes32 vs;\n            // ecrecover takes the signature parameters, and the only way to get them\n            // currently is to use assembly.\n            assembly {\n                r := mload(add(signature, 0x20))\n                vs := mload(add(signature, 0x40))\n            }\n            return tryRecover(hash, r, vs);\n        } else {\n            return (address(0), RecoverError.InvalidSignatureLength);\n        }\n    }\n\n    /**\n     * @dev Returns the address that signed a hashed message (`hash`) with\n     * `signature`. This address can then be used for verification purposes.\n     *\n     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:\n     * this function rejects them by requiring the `s` value to be in the lower\n     * half order, and the `v` value to be either 27 or 28.\n     *\n     * IMPORTANT: `hash` _must_ be the result of a hash operation for the\n     * verification to be secure: it is possible to craft signatures that\n     * recover to arbitrary addresses for non-hashed data. A safe way to ensure\n     * this is by receiving a hash of the original message (which may otherwise\n     * be too long), and then calling {toEthSignedMessageHash} on it.\n     */\n    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {\n        (address recovered, RecoverError error) = tryRecover(hash, signature);\n        _throwError(error);\n        return recovered;\n    }\n\n    /**\n     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.\n     *\n     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]\n     *\n     * _Available since v4.3._\n     */\n    function tryRecover(\n        bytes32 hash,\n        bytes32 r,\n        bytes32 vs\n    ) internal pure returns (address, RecoverError) {\n        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);\n        uint8 v = uint8((uint256(vs) >> 255) + 27);\n        return tryRecover(hash, v, r, s);\n    }\n\n    /**\n     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.\n     *\n     * _Available since v4.2._\n     */\n    function recover(\n        bytes32 hash,\n        bytes32 r,\n        bytes32 vs\n    ) internal pure returns (address) {\n        (address recovered, RecoverError error) = tryRecover(hash, r, vs);\n        _throwError(error);\n        return recovered;\n    }\n\n    /**\n     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,\n     * `r` and `s` signature fields separately.\n     *\n     * _Available since v4.3._\n     */\n    function tryRecover(\n        bytes32 hash,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) internal pure returns (address, RecoverError) {\n        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature\n        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines\n        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most\n        // signatures from current libraries generate a unique signature with an s-value in the lower half order.\n        //\n        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value\n        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or\n        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept\n        // these malleable signatures as well.\n        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {\n            return (address(0), RecoverError.InvalidSignatureS);\n        }\n        if (v != 27 && v != 28) {\n            return (address(0), RecoverError.InvalidSignatureV);\n        }\n\n        // If the signature is valid (and not malleable), return the signer address\n        address signer = ecrecover(hash, v, r, s);\n        if (signer == address(0)) {\n            return (address(0), RecoverError.InvalidSignature);\n        }\n\n        return (signer, RecoverError.NoError);\n    }\n\n    /**\n     * @dev Overload of {ECDSA-recover} that receives the `v`,\n     * `r` and `s` signature fields separately.\n     */\n    function recover(\n        bytes32 hash,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) internal pure returns (address) {\n        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);\n        _throwError(error);\n        return recovered;\n    }\n\n    /**\n     * @dev Returns an Ethereum Signed Message, created from a `hash`. This\n     * produces hash corresponding to the one signed with the\n     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]\n     * JSON-RPC method as part of EIP-191.\n     *\n     * See {recover}.\n     */\n    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {\n        // 32 is the length in bytes of hash,\n        // enforced by the type signature above\n        return keccak256(abi.encodePacked(\"\\x19Ethereum Signed Message:\\n32\", hash));\n    }\n\n    /**\n     * @dev Returns an Ethereum Signed Message, created from `s`. This\n     * produces hash corresponding to the one signed with the\n     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]\n     * JSON-RPC method as part of EIP-191.\n     *\n     * See {recover}.\n     */\n    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {\n        return keccak256(abi.encodePacked(\"\\x19Ethereum Signed Message:\\n\", Strings.toString(s.length), s));\n    }\n\n    /**\n     * @dev Returns an Ethereum Signed Typed Data, created from a\n     * `domainSeparator` and a `structHash`. This produces hash corresponding\n     * to the one signed with the\n     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]\n     * JSON-RPC method as part of EIP-712.\n     *\n     * See {recover}.\n     */\n    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {\n        return keccak256(abi.encodePacked(\"\\x19\\x01\", domainSeparator, structHash));\n    }\n}\n"
    },
    "@shoyunft/contracts/contracts/interfaces/INFT721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.5.0;\n\nimport \"./IBaseNFT721.sol\";\nimport \"./IBaseExchange.sol\";\n\ninterface INFT721 is IBaseNFT721, IBaseExchange {\n    event SetRoyaltyFeeRecipient(address recipient);\n    event SetRoyaltyFee(uint8 fee);\n\n    function initialize(\n        address _owner,\n        string calldata _name,\n        string calldata _symbol,\n        uint256[] calldata tokenIds,\n        address royaltyFeeRecipient,\n        uint8 royaltyFee\n    ) external;\n\n    function initialize(\n        address _owner,\n        string calldata _name,\n        string calldata _symbol,\n        uint256 toTokenId,\n        address royaltyFeeRecipient,\n        uint8 royaltyFee\n    ) external;\n\n    function DOMAIN_SEPARATOR() external view override(IBaseNFT721, IBaseExchange) returns (bytes32);\n\n    function factory() external view override(IBaseNFT721, IBaseExchange) returns (address);\n\n    function setRoyaltyFeeRecipient(address _royaltyFeeRecipient) external;\n\n    function setRoyaltyFee(uint8 _royaltyFee) external;\n}\n"
    },
    "@openzeppelin/contracts/utils/Strings.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n    bytes16 private constant _HEX_SYMBOLS = \"0123456789abcdef\";\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n     */\n    function toString(uint256 value) internal pure returns (string memory) {\n        // Inspired by OraclizeAPI's implementation - MIT licence\n        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol\n\n        if (value == 0) {\n            return \"0\";\n        }\n        uint256 temp = value;\n        uint256 digits;\n        while (temp != 0) {\n            digits++;\n            temp /= 10;\n        }\n        bytes memory buffer = new bytes(digits);\n        while (value != 0) {\n            digits -= 1;\n            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));\n            value /= 10;\n        }\n        return string(buffer);\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n     */\n    function toHexString(uint256 value) internal pure returns (string memory) {\n        if (value == 0) {\n            return \"0x00\";\n        }\n        uint256 temp = value;\n        uint256 length = 0;\n        while (temp != 0) {\n            length++;\n            temp >>= 8;\n        }\n        return toHexString(value, length);\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n     */\n    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n        bytes memory buffer = new bytes(2 * length + 2);\n        buffer[0] = \"0\";\n        buffer[1] = \"x\";\n        for (uint256 i = 2 * length + 1; i > 1; --i) {\n            buffer[i] = _HEX_SYMBOLS[value & 0xf];\n            value >>= 4;\n        }\n        require(value == 0, \"Strings: hex length insufficient\");\n        return string(buffer);\n    }\n}\n"
    },
    "@shoyunft/contracts/contracts/interfaces/IBaseNFT721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.5.0;\n\nimport \"@openzeppelin/contracts/token/ERC721/IERC721.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol\";\n\nimport \"./IOwnable.sol\";\n\ninterface IBaseNFT721 is IERC721, IERC721Metadata, IOwnable {\n    event SetTokenURI(uint256 indexed tokenId, string uri);\n    event SetBaseURI(string uri);\n    event ParkTokenIds(uint256 toTokenId);\n    event Burn(uint256 indexed tokenId, uint256 indexed label, bytes32 data);\n\n    function PERMIT_TYPEHASH() external view returns (bytes32);\n\n    function PERMIT_ALL_TYPEHASH() external view returns (bytes32);\n\n    function DOMAIN_SEPARATOR() external view returns (bytes32);\n\n    function factory() external view returns (address);\n\n    function nonces(uint256 tokenId) external view returns (uint256);\n\n    function noncesForAll(address account) external view returns (uint256);\n\n    function parked(uint256 tokenId) external view returns (bool);\n\n    function initialize(\n        string calldata name,\n        string calldata symbol,\n        address _owner\n    ) external;\n\n    function setTokenURI(uint256 id, string memory uri) external;\n\n    function setBaseURI(string memory uri) external;\n\n    function parkTokenIds(uint256 toTokenId) external;\n\n    function mint(\n        address to,\n        uint256 tokenId,\n        bytes calldata data\n    ) external;\n\n    function mintBatch(\n        address to,\n        uint256[] calldata tokenIds,\n        bytes calldata data\n    ) external;\n\n    function burn(\n        uint256 tokenId,\n        uint256 label,\n        bytes32 data\n    ) external;\n\n    function burnBatch(uint256[] calldata tokenIds) external;\n\n    function permit(\n        address spender,\n        uint256 tokenId,\n        uint256 deadline,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) external;\n\n    function permitAll(\n        address owner,\n        address spender,\n        uint256 deadline,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) external;\n}\n"
    },
    "@shoyunft/contracts/contracts/interfaces/IBaseExchange.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.5.0;\n\nimport \"../libraries/Orders.sol\";\n\ninterface IBaseExchange {\n    event Cancel(bytes32 indexed hash);\n    event Claim(\n        bytes32 indexed hash,\n        address bidder,\n        uint256 amount,\n        uint256 price,\n        address recipient,\n        address referrer\n    );\n    event Bid(bytes32 indexed hash, address bidder, uint256 amount, uint256 price, address recipient, address referrer);\n    event UpdateApprovedBidHash(\n        address indexed proxy,\n        bytes32 indexed askHash,\n        address indexed bidder,\n        bytes32 bidHash\n    );\n\n    function DOMAIN_SEPARATOR() external view returns (bytes32);\n\n    function factory() external view returns (address);\n\n    function canTrade(address token) external view returns (bool);\n\n    function bestBid(bytes32 hash)\n        external\n        view\n        returns (\n            address bidder,\n            uint256 amount,\n            uint256 price,\n            address recipient,\n            address referrer,\n            uint256 blockNumber\n        );\n\n    function isCancelledOrClaimed(bytes32 hash) external view returns (bool);\n\n    function amountFilled(bytes32 hash) external view returns (uint256);\n\n    function approvedBidHash(\n        address proxy,\n        bytes32 askHash,\n        address bidder\n    ) external view returns (bytes32 bidHash);\n\n    function cancel(Orders.Ask memory order) external;\n\n    function updateApprovedBidHash(\n        bytes32 askHash,\n        address bidder,\n        bytes32 bidHash\n    ) external;\n\n    function bid(Orders.Ask memory askOrder, Orders.Bid memory bidOrder) external returns (bool executed);\n\n    function bid(\n        Orders.Ask memory askOrder,\n        uint256 bidAmount,\n        uint256 bidPrice,\n        address bidRecipient,\n        address bidReferrer\n    ) external returns (bool executed);\n\n    function claim(Orders.Ask memory order) external;\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/IERC721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../../utils/introspection/IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC721 compliant contract.\n */\ninterface IERC721 is IERC165 {\n    /**\n     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.\n     */\n    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.\n     */\n    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);\n\n    /**\n     * @dev Returns the number of tokens in ``owner``'s account.\n     */\n    function balanceOf(address owner) external view returns (uint256 balance);\n\n    /**\n     * @dev Returns the owner of the `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function ownerOf(uint256 tokenId) external view returns (address owner);\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n     * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Transfers `tokenId` token from `from` to `to`.\n     *\n     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must be owned by `from`.\n     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Gives permission to `to` to transfer `tokenId` token to another account.\n     * The approval is cleared when the token is transferred.\n     *\n     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.\n     *\n     * Requirements:\n     *\n     * - The caller must own the token or be an approved operator.\n     * - `tokenId` must exist.\n     *\n     * Emits an {Approval} event.