{"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\u0027t 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 \u003e 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity\u0027s `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 \u003e= 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 \u003e= 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\u0027t, 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 \u003e 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"},"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"},"DRONES.sol":{"content":"///////////////////////////////////////////////////////////////////////////\r\n//                                                                       //\r\n//▄▄▄█████▓ ██▀███   ██▓ ██▓███   ██▓    ▓█████      ██████  ██▓▒██   ██▒//\r\n//▓  ██▒ ▓▒▓██ ▒ ██▒▓██▒▓██░  ██▒▓██▒    ▓█   ▀    ▒██    ▒ ▓██▒▒▒ █ █ ▒░//\r\n//▒ ▓██░ ▒░▓██ ░▄█ ▒▒██▒▓██░ ██▓▒▒██░    ▒███      ░ ▓██▄   ▒██▒░░  █   ░//\r\n//░ ▓██▓ ░ ▒██▀▀█▄  ░██░▒██▄█▓▒ ▒▒██░    ▒▓█  ▄      ▒   ██▒░██░ ░ █ █ ▒ //\r\n//  ▒██▒ ░ ░██▓ ▒██▒░██░▒██▒ ░  ░░██████▒░▒████▒   ▒██████▒▒░██░▒██▒ ▒██▒//\r\n//  ▒ ░░   ░ ▒▓ ░▒▓░░▓  ▒▓▒░ ░  ░░ ▒░▓  ░░░ ▒░ ░   ▒ ▒▓▒ ▒ ░░▓  ▒▒ ░ ░▓ ░//\r\n//    ░      ░▒ ░ ▒░ ▒ ░░▒ ░     ░ ░ ▒  ░ ░ ░  ░   ░ ░▒  ░ ░ ▒ ░░░   ░▒ ░//\r\n//  ░        ░░   ░  ▒ ░░░         ░ ░      ░      ░  ░  ░   ▒ ░ ░    ░  //\r\n//            ░      ░               ░  ░   ░  ░         ░   ░   ░    ░  //\r\n//                                          SPDX-License-Identifier: MIT //\r\n///////////////////////////////////////////////////////////////////////////\r\n\r\npragma solidity ^0.8.0;\r\n\r\nimport \"./ERC721A.sol\";\r\nimport \"./Ownable.sol\";\r\nimport \"./MerkleProof.sol\";\r\n\r\ncontract DRONES is ERC721A, Ownable {\r\n  using Strings for uint256;\r\n\r\n  string baseURI;\r\n  string public baseExtension = \".json\";\r\n  string public notRevealedUri;\r\n  uint256 public maxSupply = 2999;\r\n  uint256 public nftPerAddressLimit = 1;\r\n\r\n  struct mintInfo {\r\n    uint256 metalsHeld;\r\n    uint256 tokenID;\r\n  }\r\n\r\n  bool public paused = true;\r\n  bool public revealed = false;\r\n  bool public pausedBurn = true;\r\n\r\n  mapping(address =\u003e mintInfo) mintedTokenIDs;\r\n  mapping(address =\u003e uint256) public addressMintedBalance;\r\n  mapping(address =\u003e bool) public giveaway;\r\n  mapping(address =\u003e bool) public hasMintedGW;\r\n\r\n  bytes32 public merkleRoot;\r\n\r\n  address[] mintedAddreses;\r\n  uint256[] public silverMints;\r\n  uint256[] public goldMints;\r\n\r\n  address public constant LIQUID_METALS = 0xA49F31C7C90137e8d76FCf339E242e97B8f417D9;\r\n\r\n  constructor(\r\n    string memory _name,\r\n    string memory _symbol,\r\n    string memory _initBaseURI,\r\n    string memory _initNotRevealedUri\r\n  ) ERC721A(_name, _symbol) {\r\n    setBaseURI(_initBaseURI);\r\n    setNotRevealedURI(_initNotRevealedUri);\r\n  }\r\n\r\n  // internal\r\n  function _baseURI() internal view virtual override returns (string memory) {\r\n    return baseURI;\r\n  }\r\n\r\n  // public\r\n  function mint(bytes32[] calldata _merkleProof) public {\r\n    uint256 supply = totalSupply();\r\n    uint256 balanceOfUser = ERC721A(LIQUID_METALS).balanceOf(msg.sender);\r\n\r\n    require(!paused, \"Public sale is paused.\");\r\n    require(isWhitelisted(msg.sender, _merkleProof), \"User is not whitelisted.\");\r\n    require(tx.origin == msg.sender, \"Origin doesnt match sender.\");\r\n    require(supply + 1 \u003c= maxSupply, \"Max supply reached\");\r\n    \r\n    uint256 localnftPerAddressLimit = nftPerAddressLimit;\r\n    uint256 senderMintCount = addressMintedBalance[msg.sender];\r\n\r\n    if(balanceOfUser \u003e= 15) {\r\n      localnftPerAddressLimit = 2;\r\n    }\r\n    require(senderMintCount + 1 \u003c= localnftPerAddressLimit, \"Max NFT per address exceeded\");\r\n\r\n    _safeMint(msg.sender, 1);\r\n    addressMintedBalance[msg.sender] += 1;\r\n\r\n    if (senderMintCount == 0) {\r\n      mintedTokenIDs[msg.sender] = mintInfo(balanceOfUser, supply);\r\n      mintedAddreses.push(msg.sender);\r\n    } else if (senderMintCount == 1) {\r\n      goldMints.push(supply);\r\n    }\r\n  }\r\n\r\n  function mintGiveaway() public {\r\n    uint256 supply = totalSupply();\r\n    require(!paused, \"Public sale is paused.\");\r\n    require(giveaway[msg.sender], \"You are not in the giveaway winner list.\");\r\n    require(!hasMintedGW[msg.sender], \"Already minted the giveaway.\");\r\n    require(supply + 1 \u003c maxSupply, \"Max supply reached\");\r\n    require(tx.origin == msg.sender, \"Origin doesn\u0027t match sender\");\r\n\r\n    _safeMint(msg.sender, 1);\r\n    hasMintedGW[msg.sender] = true;\r\n    silverMints.push(supply);\r\n  }\r\n\r\n  function mintAdmin(uint256 mintAmount) external onlyOwner {\r\n    uint256 supply = totalSupply();\r\n    require(supply + mintAmount \u003c maxSupply, \"Too many tokens.\");\r\n    _safeMint(msg.sender, mintAmount);\r\n  }\r\n\r\n  function burnToken(uint256 tokenId) public {\r\n    require(!pausedBurn, \"Burn is paused\");\r\n    _burn(tokenId);\r\n  }\r\n\r\n  function walletOfOwner(address _owner)\r\n    public\r\n    view\r\n    returns (uint256[] memory)\r\n  {\r\n    uint256 ownerTokenCount = balanceOf(_owner);\r\n    uint256[] memory tokenIds = new uint256[](ownerTokenCount);\r\n    for (uint256 i; i \u003c ownerTokenCount; i++) {\r\n      tokenIds[i] = tokenOfOwnerByIndex(_owner, i);\r\n    }\r\n    return tokenIds;\r\n  }\r\n\r\n  function tokenURI(uint256 tokenId)\r\n    public\r\n    view\r\n    virtual\r\n    override\r\n    returns (string memory)\r\n  {\r\n    require(\r\n      _exists(tokenId),\r\n      \"ERC721Metadata: URI query for nonexistent token\"\r\n    );\r\n    \r\n    if(revealed == false) {\r\n        return notRevealedUri;\r\n    }\r\n\r\n    string memory currentBaseURI = _baseURI();\r\n    return bytes(currentBaseURI).length \u003e 0\r\n        ? string(abi.encodePacked(currentBaseURI, tokenId.toString(), baseExtension))\r\n        : \"\";\r\n  }\r\n\r\n  function reveal() public onlyOwner {\r\n    revealed = true;\r\n  }\r\n\r\n  function setNftPerAddressLimit(uint256 _limit) public onlyOwner {\r\n    nftPerAddressLimit = _limit;\r\n  }\r\n  \r\n  function setNotRevealedURI(string memory _notRevealedURI) public onlyOwner {\r\n    notRevealedUri = _notRevealedURI;\r\n  }\r\n\r\n  function setBaseURI(string memory _newBaseURI) public onlyOwner {\r\n    baseURI = _newBaseURI;\r\n  }\r\n\r\n  function setBaseExtension(string memory _newBaseExtension) public onlyOwner {\r\n    baseExtension = _newBaseExtension;\r\n  }\r\n\r\n  function pause(bool _state) public onlyOwner {\r\n    paused = _state;\r\n  }\r\n\r\n  function pauseBurn(bool _state) public onlyOwner {\r\n    pausedBurn = _state;\r\n  }\r\n\r\n  function getMinters() public view returns (address[] memory minted) { return mintedAddreses; }\r\n  function getSilvers() public view returns (uint256[] memory silvers) { return silverMints; }\r\n  function getGolds() public view returns (uint256[] memory golds) { return goldMints; }\r\n  \r\n  function getMinterInfo(address _minter) public view returns (uint256 minterMetalsHeld, uint256 mintedTokenID){\r\n    require(addressMintedBalance[_minter] \u003e= 1, \"ERROR: Address has not minted the NFT from the main sale.\");\r\n    mintInfo memory minterInfo = mintedTokenIDs[_minter];\r\n    return (minterInfo.metalsHeld, minterInfo.tokenID);\r\n  }\r\n\r\n  function isWhitelisted(address _user, bytes32[] calldata _merkleProof) public view returns (bool) {\r\n    bytes32 leaf = keccak256(abi.encodePacked(_user));\r\n    return MerkleProof.verify(_merkleProof, merkleRoot, leaf);\r\n  }\r\n\r\n  function setMerkleRoot(bytes32 _merkleRoot) external onlyOwner {\r\n    merkleRoot = _merkleRoot;\r\n  }\r\n\r\n  function isGiveaway(address _user) public view returns (bool) {\r\n    return giveaway[_user];\r\n  }\r\n\r\n  function addGiveaway(address[] calldata addresses) external onlyOwner {\r\n    for (uint256 i = 0; i \u003c addresses.length; i++) {\r\n      giveaway[addresses[i]] = true;\r\n    }\r\n  }\r\n}"},"ERC165.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n        return interfaceId == type(IERC165).interfaceId;\n    }\n}\n"},"ERC721A.sol":{"content":"// SPDX-License-Identifier: MIT\r\n// Creator: Chiru Labs\r\n\r\npragma solidity ^0.8.4;\r\n\r\nimport \u0027./IERC721.sol\u0027;\r\nimport \u0027./IERC721Receiver.sol\u0027;\r\nimport \u0027./IERC721Metadata.sol\u0027;\r\nimport \u0027./IERC721Enumerable.sol\u0027;\r\nimport \u0027./Address.sol\u0027;\r\nimport \u0027./Context.sol\u0027;\r\nimport \u0027./Strings.sol\u0027;\r\nimport \u0027./ERC165.sol\u0027;\r\n\r\nerror ApprovalCallerNotOwnerNorApproved();\r\nerror ApprovalQueryForNonexistentToken();\r\nerror ApproveToCaller();\r\nerror ApprovalToCurrentOwner();\r\nerror BalanceQueryForZeroAddress();\r\nerror MintedQueryForZeroAddress();\r\nerror BurnedQueryForZeroAddress();\r\nerror MintToZeroAddress();\r\nerror MintZeroQuantity();\r\nerror OwnerIndexOutOfBounds();\r\nerror OwnerQueryForNonexistentToken();\r\nerror TokenIndexOutOfBounds();\r\nerror TransferCallerNotOwnerNorApproved();\r\nerror TransferFromIncorrectOwner();\r\nerror TransferToNonERC721ReceiverImplementer();\r\nerror TransferToZeroAddress();\r\nerror URIQueryForNonexistentToken();\r\n\r\n/**\r\n * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including\r\n * the Metadata and Enumerable extension. Built to optimize for lower gas during batch mints.\r\n *\r\n * Assumes serials are sequentially minted starting at 0 (e.g. 0, 1, 2, 3..).\r\n *\r\n * Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.\r\n *\r\n * Assumes that the maximum token id cannot exceed 2**128 - 1 (max value of uint128).\r\n */\r\ncontract ERC721A is Context, ERC165, IERC721, IERC721Metadata, IERC721Enumerable {\r\n    using Address for address;\r\n    using Strings for uint256;\r\n\r\n    // Compiler will pack this into a single 256bit word.\r\n    struct TokenOwnership {\r\n        // The address of the owner.\r\n        address addr;\r\n        // Keeps track of the start time of ownership with minimal overhead for tokenomics.\r\n        uint64 startTimestamp;\r\n        // Whether the token has been burned.\r\n        bool burned;\r\n    }\r\n\r\n    // Compiler will pack this into a single 256bit word.\r\n    struct AddressData {\r\n        // Realistically, 2**64-1 is more than enough.\r\n        uint64 balance;\r\n        // Keeps track of mint count with minimal overhead for tokenomics.\r\n        uint64 numberMinted;\r\n        // Keeps track of burn count with minimal overhead for tokenomics.\r\n        uint64 numberBurned;\r\n    }\r\n\r\n    // The tokenId of the next token to be minted.\r\n    uint256 internal _currentIndex;\r\n\r\n    // The number of tokens burned.\r\n    uint256 internal _burnCounter;\r\n\r\n    // Token name\r\n    string private _name;\r\n\r\n    // Token symbol\r\n    string private _symbol;\r\n\r\n    // Mapping from token ID to ownership details\r\n    // An empty struct value does not necessarily mean the token is unowned. See ownershipOf implementation for details.\r\n    mapping(uint256 =\u003e TokenOwnership) internal _ownerships;\r\n\r\n    // Mapping owner address to address data\r\n    mapping(address =\u003e AddressData) private _addressData;\r\n\r\n    // Mapping from token ID to approved address\r\n    mapping(uint256 =\u003e address) private _tokenApprovals;\r\n\r\n    // Mapping from owner to operator approvals\r\n    mapping(address =\u003e mapping(address =\u003e bool)) private _operatorApprovals;\r\n\r\n    constructor(string memory name_, string memory symbol_) {\r\n        _name = name_;\r\n        _symbol = symbol_;\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Enumerable-totalSupply}.\r\n     */\r\n    function totalSupply() public view override returns (uint256) {\r\n        // Counter underflow is impossible as _burnCounter cannot be incremented\r\n        // more than _currentIndex times\r\n        unchecked {\r\n            return _currentIndex - _burnCounter;    \r\n        }\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Enumerable-tokenByIndex}.\r\n     * This read function is O(totalSupply). If calling from a separate contract, be sure to test gas first.\r\n     * It may also degrade with extremely large collection sizes (e.g \u003e\u003e 10000), test for your use case.\r\n     */\r\n    function tokenByIndex(uint256 index) public view override returns (uint256) {\r\n        uint256 numMintedSoFar = _currentIndex;\r\n        uint256 tokenIdsIdx;\r\n\r\n        // Counter overflow is impossible as the loop breaks when\r\n        // uint256 i is equal to another uint256 numMintedSoFar.\r\n        unchecked {\r\n            for (uint256 i; i \u003c numMintedSoFar; i++) {\r\n                TokenOwnership memory ownership = _ownerships[i];\r\n                if (!ownership.burned) {\r\n                    if (tokenIdsIdx == index) {\r\n                        return i;\r\n                    }\r\n                    tokenIdsIdx++;\r\n                }\r\n            }\r\n        }\r\n        revert TokenIndexOutOfBounds();\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.\r\n     * This read function is O(totalSupply). If calling from a separate contract, be sure to test gas first.\r\n     * It may also degrade with extremely large collection sizes (e.g \u003e\u003e 10000), test for your use case.\r\n     */\r\n    function tokenOfOwnerByIndex(address owner, uint256 index) public view override returns (uint256) {\r\n        if (index \u003e= balanceOf(owner)) revert OwnerIndexOutOfBounds();\r\n        uint256 numMintedSoFar = _currentIndex;\r\n        uint256 tokenIdsIdx;\r\n        address currOwnershipAddr;\r\n\r\n        // Counter overflow is impossible as the loop breaks when\r\n        // uint256 i is equal to another uint256 numMintedSoFar.\r\n        unchecked {\r\n            for (uint256 i; i \u003c numMintedSoFar; i++) {\r\n                TokenOwnership memory ownership = _ownerships[i];\r\n                if (ownership.burned) {\r\n                    continue;\r\n                }\r\n                if (ownership.addr != address(0)) {\r\n                    currOwnershipAddr = ownership.addr;\r\n                }\r\n                if (currOwnershipAddr == owner) {\r\n                    if (tokenIdsIdx == index) {\r\n                        return i;\r\n                    }\r\n                    tokenIdsIdx++;\r\n                }\r\n            }\r\n        }\r\n\r\n        // Execution should never reach this point.\r\n        revert();\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC165-supportsInterface}.\r\n     */\r\n    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\r\n        return\r\n            interfaceId == type(IERC721).interfaceId ||\r\n            interfaceId == type(IERC721Metadata).interfaceId ||\r\n            interfaceId == type(IERC721Enumerable).interfaceId ||\r\n            super.supportsInterface(interfaceId);\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-balanceOf}.\r\n     */\r\n    function balanceOf(address owner) public view override returns (uint256) {\r\n        if (owner == address(0)) revert BalanceQueryForZeroAddress();\r\n        return uint256(_addressData[owner].balance);\r\n    }\r\n\r\n    function _numberMinted(address owner) internal view returns (uint256) {\r\n        if (owner == address(0)) revert MintedQueryForZeroAddress();\r\n        return uint256(_addressData[owner].numberMinted);\r\n    }\r\n\r\n    function _numberBurned(address owner) internal view returns (uint256) {\r\n        if (owner == address(0)) revert BurnedQueryForZeroAddress();\r\n        return uint256(_addressData[owner].numberBurned);\r\n    }\r\n\r\n    /**\r\n     * Gas spent here starts off proportional to the maximum mint batch size.\r\n     * It gradually moves to O(1) as tokens get transferred around in the collection over time.\r\n     */\r\n    function ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {\r\n        uint256 curr = tokenId;\r\n\r\n        unchecked {\r\n            if (curr \u003c _currentIndex) {\r\n                TokenOwnership memory ownership = _ownerships[curr];\r\n                if (!ownership.burned) {\r\n                    if (ownership.addr != address(0)) {\r\n                        return ownership;\r\n                    }\r\n                    // Invariant: \r\n                    // There will always be an ownership that has an address and is not burned \r\n                    // before an ownership that does not have an address and is not burned.\r\n                    // Hence, curr will not underflow.\r\n                    while (true) {\r\n                        curr--;\r\n                        ownership = _ownerships[curr];\r\n                        if (ownership.addr != address(0)) {\r\n                            return ownership;\r\n                        }\r\n                    }\r\n                }\r\n            }\r\n        }\r\n        revert OwnerQueryForNonexistentToken();\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-ownerOf}.\r\n     */\r\n    function ownerOf(uint256 tokenId) public view override returns (address) {\r\n        return ownershipOf(tokenId).addr;\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Metadata-name}.\r\n     */\r\n    function name() public view virtual override returns (string memory) {\r\n        return _name;\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Metadata-symbol}.\r\n     */\r\n    function symbol() public view virtual override returns (string memory) {\r\n        return _symbol;\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721Metadata-tokenURI}.\r\n     */\r\n    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {\r\n        if (!_exists(tokenId)) revert URIQueryForNonexistentToken();\r\n\r\n        string memory baseURI = _baseURI();\r\n        return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : \u0027\u0027;\r\n    }\r\n\r\n    /**\r\n     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each\r\n     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty\r\n     * by default, can be overriden in child contracts.\r\n     */\r\n    function _baseURI() internal view virtual returns (string memory) {\r\n        return \u0027\u0027;\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-approve}.\r\n     */\r\n    function approve(address to, uint256 tokenId) public override {\r\n        address owner = ERC721A.ownerOf(tokenId);\r\n        if (to == owner) revert ApprovalToCurrentOwner();\r\n\r\n        if (_msgSender() != owner \u0026\u0026 !isApprovedForAll(owner, _msgSender())) {\r\n            revert ApprovalCallerNotOwnerNorApproved();\r\n        }\r\n\r\n        _approve(to, tokenId, owner);\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-getApproved}.\r\n     */\r\n    function getApproved(uint256 tokenId) public view override returns (address) {\r\n        if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();\r\n\r\n        return _tokenApprovals[tokenId];\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-setApprovalForAll}.\r\n     */\r\n    function setApprovalForAll(address operator, bool approved) public override {\r\n        if (operator == _msgSender()) revert ApproveToCaller();\r\n\r\n        _operatorApprovals[_msgSender()][operator] = approved;\r\n        emit ApprovalForAll(_msgSender(), operator, approved);\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-isApprovedForAll}.\r\n     */\r\n    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {\r\n        return _operatorApprovals[owner][operator];\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-transferFrom}.\r\n     */\r\n    function transferFrom(\r\n        address from,\r\n        address to,\r\n        uint256 tokenId\r\n    ) public virtual override {\r\n        _transfer(from, to, tokenId);\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-safeTransferFrom}.\r\n     */\r\n    function safeTransferFrom(\r\n        address from,\r\n        address to,\r\n        uint256 tokenId\r\n    ) public virtual override {\r\n        safeTransferFrom(from, to, tokenId, \u0027\u0027);\r\n    }\r\n\r\n    /**\r\n     * @dev See {IERC721-safeTransferFrom}.\r\n     */\r\n    function safeTransferFrom(\r\n        address from,\r\n        address to,\r\n        uint256 tokenId,\r\n        bytes memory _data\r\n    ) public virtual override {\r\n        _transfer(from, to, tokenId);\r\n        if (!_checkOnERC721Received(from, to, tokenId, _data)) {\r\n            revert TransferToNonERC721ReceiverImplementer();\r\n        }\r\n    }\r\n\r\n    /**\r\n     * @dev Returns whether `tokenId` exists.\r\n     *\r\n     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.\r\n     *\r\n     * Tokens start existing when they are minted (`_mint`),\r\n     */\r\n    function _exists(uint256 tokenId) internal view returns (bool) {\r\n        return tokenId \u003c _currentIndex \u0026\u0026 !_ownerships[tokenId].burned;\r\n    }\r\n\r\n    function _safeMint(address to, uint256 quantity) internal {\r\n        _safeMint(to, quantity, \u0027\u0027);\r\n    }\r\n\r\n    /**\r\n     * @dev Safely mints `quantity` tokens and transfers them to `to`.\r\n     *\r\n     * Requirements:\r\n     *\r\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called for each safe transfer.\r\n     * - `quantity` must be greater than 0.\r\n     *\r\n     * Emits a {Transfer} event.\r\n     */\r\n    function _safeMint(\r\n        address to,\r\n        uint256 quantity,\r\n        bytes memory _data\r\n    ) internal {\r\n        _mint(to, quantity, _data, true);\r\n    }\r\n\r\n    /**\r\n     * @dev Mints `quantity` tokens and transfers them to `to`.\r\n     *\r\n     * Requirements:\r\n     *\r\n     * - `to` cannot be the zero address.\r\n     * - `quantity` must be greater than 0.\r\n     *\r\n     * Emits a {Transfer} event.\r\n     */\r\n    function _mint(\r\n        address to,\r\n        uint256 quantity,\r\n        bytes memory _data,\r\n        bool safe\r\n    ) internal {\r\n        uint256 startTokenId = _currentIndex;\r\n        if (to == address(0)) revert MintToZeroAddress();\r\n        if (quantity == 0) revert MintZeroQuantity();\r\n\r\n        _beforeTokenTransfers(address(0), to, startTokenId, quantity);\r\n\r\n        // Overflows are incredibly unrealistic.\r\n        // balance or numberMinted overflow if current value of either + quantity \u003e 3.4e38 (2**128) - 1\r\n        // updatedIndex overflows if _currentIndex + quantity \u003e 3.4e38 (2**128) - 1\r\n        unchecked {\r\n            _addressData[to].balance += uint64(quantity);\r\n            _addressData[to].numberMinted += uint64(quantity);\r\n\r\n            _ownerships[startTokenId].addr = to;\r\n            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);\r\n\r\n            uint256 updatedIndex = startTokenId;\r\n\r\n            for (uint256 i; i \u003c quantity; i++) {\r\n                emit Transfer(address(0), to, updatedIndex);\r\n                if (safe \u0026\u0026 !_checkOnERC721Received(address(0), to, updatedIndex, _data)) {\r\n                    revert TransferToNonERC721ReceiverImplementer();\r\n                }\r\n                updatedIndex++;\r\n            }\r\n\r\n            _currentIndex = uint128(updatedIndex);\r\n        }\r\n        _afterTokenTransfers(address(0), to, startTokenId, quantity);\r\n    }\r\n\r\n    /**\r\n     * @dev Transfers `tokenId` from `from` to `to`.\r\n     *\r\n     * Requirements:\r\n     *\r\n     * - `to` cannot be the zero address.\r\n     * - `tokenId` token must be owned by `from`.\r\n     *\r\n     * Emits a {Transfer} event.\r\n     */\r\n    function _transfer(\r\n        address from,\r\n        address to,\r\n        uint256 tokenId\r\n    ) private {\r\n        TokenOwnership memory prevOwnership = ownershipOf(tokenId);\r\n\r\n        bool isApprovedOrOwner = (_msgSender() == prevOwnership.addr ||\r\n            isApprovedForAll(prevOwnership.addr, _msgSender()) ||\r\n            getApproved(tokenId) == _msgSender());\r\n\r\n        if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();\r\n        if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();\r\n        if (to == address(0)) revert TransferToZeroAddress();\r\n\r\n        _beforeTokenTransfers(from, to, tokenId, 1);\r\n\r\n        // Clear approvals from the previous owner\r\n        _approve(address(0), tokenId, prevOwnership.addr);\r\n\r\n        // Underflow of the sender\u0027s balance is impossible because we check for\r\n        // ownership above and the recipient\u0027s balance can\u0027t realistically overflow.\r\n        // Counter overflow is incredibly unrealistic as tokenId would have to be 2**128.\r\n        unchecked {\r\n            _addressData[from].balance -= 1;\r\n            _addressData[to].balance += 1;\r\n\r\n            _ownerships[tokenId].addr = to;\r\n            _ownerships[tokenId].startTimestamp = uint64(block.timestamp);\r\n\r\n            // If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.\r\n            // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.\r\n            uint256 nextTokenId = tokenId + 1;\r\n            if (_ownerships[nextTokenId].addr == address(0)) {\r\n                // This will suffice for checking _exists(nextTokenId),\r\n                // as a burned slot cannot contain the zero address.\r\n                if (nextTokenId \u003c _currentIndex) {\r\n                    _ownerships[nextTokenId].addr = prevOwnership.addr;\r\n                    _ownerships[nextTokenId].startTimestamp = prevOwnership.startTimestamp;\r\n                }\r\n            }\r\n        }\r\n\r\n        emit Transfer(from, to, tokenId);\r\n        _afterTokenTransfers(from, to, tokenId, 1);\r\n    }\r\n\r\n    /**\r\n     * @dev Destroys `tokenId`.\r\n     * The approval is cleared when the token is burned.\r\n     *\r\n     * Requirements:\r\n     *\r\n     * - `tokenId` must exist.\r\n     *\r\n     * Emits a {Transfer} event.\r\n     */\r\n    function _burn(uint256 tokenId) internal virtual {\r\n        TokenOwnership memory prevOwnership = ownershipOf(tokenId);\r\n\r\n        _beforeTokenTransfers(prevOwnership.addr, address(0), tokenId, 1);\r\n\r\n        // Clear approvals from the previous owner\r\n        _approve(address(0), tokenId, prevOwnership.addr);\r\n\r\n        // Underflow of the sender\u0027s balance is impossible because we check for\r\n        // ownership above and the recipient\u0027s balance can\u0027t realistically overflow.\r\n        // Counter overflow is incredibly unrealistic as tokenId would have to be 2**128.\r\n        unchecked {\r\n            _addressData[prevOwnership.addr].balance -= 1;\r\n            _addressData[prevOwnership.addr].numberBurned += 1;\r\n\r\n            // Keep track of who burned the token, and the timestamp of burning.\r\n            _ownerships[tokenId].addr = prevOwnership.addr;\r\n            _ownerships[tokenId].startTimestamp = uint64(block.timestamp);\r\n            _ownerships[tokenId].burned = true;\r\n\r\n            // If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.\r\n            // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.\r\n            uint256 nextTokenId = tokenId + 1;\r\n            if (_ownerships[nextTokenId].addr == address(0)) {\r\n                // This will suffice for checking _exists(nextTokenId),\r\n                // as a burned slot cannot contain the zero address.\r\n                if (nextTokenId \u003c _currentIndex) {\r\n                    _ownerships[nextTokenId].addr = prevOwnership.addr;\r\n                    _ownerships[nextTokenId].startTimestamp = prevOwnership.startTimestamp;\r\n                }\r\n            }\r\n        }\r\n\r\n        emit Transfer(prevOwnership.addr, address(0), tokenId);\r\n        _afterTokenTransfers(prevOwnership.addr, address(0), tokenId, 1);\r\n\r\n        // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.\r\n        unchecked { \r\n            _burnCounter++;\r\n        }\r\n    }\r\n\r\n    /**\r\n     * @dev Approve `to` to operate on `tokenId`\r\n     *\r\n     * Emits a {Approval} event.\r\n     */\r\n    function _approve(\r\n        address to,\r\n        uint256 tokenId,\r\n        address owner\r\n    ) private {\r\n        _tokenApprovals[tokenId] = to;\r\n        emit Approval(owner, to, tokenId);\r\n    }\r\n\r\n    /**\r\n     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.\r\n     * The call is not executed if the target address is not a contract.\r\n     *\r\n     * @param from address representing the previous owner of the given token ID\r\n     * @param to target address that will receive the tokens\r\n     * @param tokenId uint256 ID of the token to be transferred\r\n     * @param _data bytes optional data to send along with the call\r\n     * @return bool whether the call correctly returned the expected magic value\r\n     */\r\n    function _checkOnERC721Received(\r\n        address from,\r\n        address to,\r\n        uint256 tokenId,\r\n        bytes memory _data\r\n    ) private returns (bool) {\r\n        if (to.isContract()) {\r\n            try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {\r\n                return retval == IERC721Receiver(to).onERC721Received.selector;\r\n            } catch (bytes memory reason) {\r\n                if (reason.length == 0) {\r\n                    revert TransferToNonERC721ReceiverImplementer();\r\n                } else {\r\n                    assembly {\r\n                        revert(add(32, reason), mload(reason))\r\n                    }\r\n                }\r\n            }\r\n        } else {\r\n            return true;\r\n        }\r\n    }\r\n\r\n    /**\r\n     * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.\r\n     * And also called before burning one token.\r\n     *\r\n     * startTokenId - the first token id to be transferred\r\n     * quantity - the amount to be transferred\r\n     *\r\n     * Calling conditions:\r\n     *\r\n     * - When `from` and `to` are both non-zero, `from`\u0027s `tokenId` will be\r\n     * transferred to `to`.\r\n     * - When `from` is zero, `tokenId` will be minted for `to`.\r\n     * - When `to` is zero, `tokenId` will be burned by `from`.\r\n     * - `from` and `to` are never both zero.\r\n     */\r\n    function _beforeTokenTransfers(\r\n        address from,\r\n        address to,\r\n        uint256 startTokenId,\r\n        uint256 quantity\r\n    ) internal virtual {}\r\n\r\n    /**\r\n     * @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes\r\n     * minting.\r\n     * And also called after one token has been burned.\r\n     *\r\n     * startTokenId - the first token id to be transferred\r\n     * quantity - the amount to be transferred\r\n     *\r\n     * Calling conditions:\r\n     *\r\n     * - When `from` and `to` are both non-zero, `from`\u0027s `tokenId` has been\r\n     * transferred to `to`.\r\n     * - When `from` is zero, `tokenId` has been minted for `to`.\r\n     * - When `to` is zero, `tokenId` has been burned by `from`.\r\n     * - `from` and `to` are never both zero.\r\n     */\r\n    function _afterTokenTransfers(\r\n        address from,\r\n        address to,\r\n        uint256 startTokenId,\r\n        uint256 quantity\r\n    ) internal virtual {}\r\n}"},"IERC165.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n    /**\n     * @dev Returns true if this contract implements the interface defined by\n     * `interfaceId`. See the corresponding\n     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n     * to learn more about how these ids are created.\n     *\n     * This function call must use less than 30 000 gas.\n     */\n    function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n"},"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 \"./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``\u0027s 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.\n     */\n    function approve(address to, uint256 tokenId) external;\n\n    /**\n     * @dev Returns the account approved for `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function getApproved(uint256 tokenId) external view returns (address operator);\n\n    /**\n     * @dev Approve or remove `operator` as an operator for the caller.\n     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.\n     *\n     * Requirements:\n     *\n     * - The `operator` cannot be the caller.\n     *\n     * Emits an {ApprovalForAll} event.\n     */\n    function setApprovalForAll(address operator, bool _approved) external;\n\n    /**\n     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.\n     *\n     * See {setApprovalForAll}\n     */\n    function isApprovedForAll(address owner, address operator) external view returns (bool);\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`.\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 approved 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        bytes calldata data\n    ) external;\n}\n"},"IERC721Enumerable.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Enumerable is IERC721 {\n    /**\n     * @dev Returns the total amount of tokens stored by the contract.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.\n     * Use along with {balanceOf} to enumerate all of ``owner``\u0027s tokens.\n     */\n    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256);\n\n    /**\n     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.\n     * Use along with {totalSupply} to enumerate all tokens.\n     */\n    function tokenByIndex(uint256 index) external view returns (uint256);\n}\n"},"IERC721Metadata.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional metadata extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Metadata is IERC721 {\n    /**\n     * @dev Returns the token collection name.\n     */\n    function name() external view returns (string memory);\n\n    /**\n     * @dev Returns the token collection symbol.\n     */\n    function symbol() external view returns (string memory);\n\n    /**\n     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.\n     */\n    function tokenURI(uint256 tokenId) external view returns (string memory);\n}\n"},"IERC721Receiver.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @title ERC721 token receiver interface\n * @dev Interface for any contract that wants to support safeTransfers\n * from ERC721 asset contracts.\n */\ninterface IERC721Receiver {\n    /**\n     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}\n     * by `operator` from `from`, this function is called.\n     *\n     * It must return its Solidity selector to confirm the token transfer.\n     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.\n     *\n     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.\n     */\n    function onERC721Received(\n        address operator,\n        address from,\n        uint256 tokenId,\n        bytes calldata data\n    ) external returns (bytes4);\n}\n"},"MerkleProof.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/MerkleProof.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev These functions deal with verification of Merkle Trees proofs.\n *\n * The proofs can be generated using the JavaScript library\n * https://github.com/miguelmota/merkletreejs[merkletreejs].\n * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.\n *\n * See `test/utils/cryptography/MerkleProof.test.js` for some examples.\n *\n * WARNING: You should avoid using leaf values that are 64 bytes long prior to\n * hashing, or use a hash function other than keccak256 for hashing leaves.\n * This is because the concatenation of a sorted pair of internal nodes in\n * the merkle tree could be reinterpreted as a leaf value.\n */\nlibrary MerkleProof {\n    /**\n     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree\n     * defined by `root`. For this, a `proof` must be provided, containing\n     * sibling hashes on the branch from the leaf to the root of the tree. Each\n     * pair of leaves and each pair of pre-images are assumed to be sorted.\n     */\n    function verify(\n        bytes32[] memory proof,\n        bytes32 root,\n        bytes32 leaf\n    ) internal pure returns (bool) {\n        return processProof(proof, leaf) == root;\n    }\n\n    /**\n     * @dev Returns the rebuilt hash obtained by traversing a Merkle tree up\n     * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt\n     * hash matches the root of the tree. When processing the proof, the pairs\n     * of leafs \u0026 pre-images are assumed to be sorted.\n     *\n     * _Available since v4.4._\n     */\n    function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {\n        bytes32 computedHash = leaf;\n        for (uint256 i = 0; i \u003c proof.length; i++) {\n            bytes32 proofElement = proof[i];\n            if (computedHash \u003c= proofElement) {\n                // Hash(current computed hash + current element of the proof)\n                computedHash = _efficientHash(computedHash, proofElement);\n            } else {\n                // Hash(current element of the proof + current computed hash)\n                computedHash = _efficientHash(proofElement, computedHash);\n            }\n        }\n        return computedHash;\n    }\n\n    function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {\n        assembly {\n            mstore(0x00, a)\n            mstore(0x20, b)\n            value := keccak256(0x00, 0x40)\n        }\n    }\n}"},"Ownable.sol":{"content":"// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./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"},"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\u0027s 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 \u003e\u003e= 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 \u003e 1; --i) {\n            buffer[i] = _HEX_SYMBOLS[value \u0026 0xf];\n            value \u003e\u003e= 4;\n        }\n        require(value == 0, \"Strings: hex length insufficient\");\n        return string(buffer);\n    }\n}\n"}}