ETH Price: $2,155.39 (+0.36%)
Gas: 0.03 Gwei

Transaction Decoder

Block:
14809179 at May-20-2022 04:59:14 AM +UTC
Transaction Fee:
0.001764142125011983 ETH $3.80
Gas Used:
84,061 Gas / 20.986451803 Gwei

Account State Difference:

  Address   Before After State Difference Code
0x251764CE...1c6Dc7AFC
0.014419515296096835 Eth
Nonce: 606
0.012655373171084852 Eth
Nonce: 607
0.001764142125011983
0x6faD7393...941B44042
(Ezil.me : Ezil Pool 4)
348.122609290953297018 Eth348.122735382453297018 Eth0.0001260915

Execution Trace

FlufSceneAndMusic.swap( tokenId=3064, backgroundAssetLockIn=77, musicAssetLockIn=15 )
  • FLUF.ownerOf( tokenId=3064 ) => ( 0x251764CE2619b69C6784f853e1B58601c6Dc7AFC )
  • FlufSceneAndMusic.onERC1155Received( 0x251764CE2619b69C6784f853e1B58601c6Dc7AFC, 0x251764CE2619b69C6784f853e1B58601c6Dc7AFC, 77, 1, 0x )
    File 1 of 2: FlufSceneAndMusic
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "@openzeppelin/contracts/token/ERC1155/ERC1155.sol";
    import "@openzeppelin/contracts/token/ERC1155/utils/ERC1155Holder.sol";
    import "@openzeppelin/contracts/access/AccessControl.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/utils/Strings.sol";
    import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
    contract FlufSceneAndMusic is ERC1155, ERC1155Holder, Ownable {
      // ERC1155 id => Asset Name
      struct flufLocked {
        uint256 background;
        uint256 music;
      }
      struct assetDescription {
        string assetType; // Background / Music
        string assetName; // Dunes / Lambo etc
      }
      mapping(uint256 => assetDescription) public assets;
      // fluf tokenId => ERC1155 id
      mapping(uint256 => flufLocked) public flufLock;
      mapping(uint256 => bool) public flufHasDefault;
      //mapping(uint256 => uint256) public flufLock;
      event Swap(
        address by,
        uint256 musicAssetLockIn,
        uint256 backgroundAssetLockIn,
        uint256 tokenId
      );
      address public signingWallet;
      address public flufAddress;
      string public name;
      constructor() ERC1155("https://erc1155-api.fluf.world/token/") {
        name = "FLUF World: Scenes and Sounds";
      }
      function setTokenURI(string memory _tokenURI) public onlyOwner {
          _setURI(_tokenURI);
      }
      
      function getTokenURI(uint256 _id) 
        public 
        view 
        returns (string memory)
      {
        string memory idToString = Strings.toString(_id);
        string memory uri = uri(_id);
        string memory tokenURI = string(abi.encodePacked(uri, idToString));
        return tokenURI;
      }
      function setContractName(string memory _name) public onlyOwner {
        name = _name;
      }
      function setFlufAddress(address _address) public onlyOwner {
        flufAddress = _address;
      }
      function updateSigningWallet(address _address) public onlyOwner {
        signingWallet = _address;
      }
      function setDefaultForFluf(
        uint256 _flufId,
        uint256 _defaultBackground,
        uint256 _defaultMusic
      ) internal {
        // Person has to be the owner of the fluf that he is setting the default for
        require(flufHasDefault[_flufId] != true, "Fluf default was already set");
        require(isFlufOwner(_flufId, msg.sender), "You do not own this FLUF");
        flufLock[_flufId].background = _defaultBackground;
        flufLock[_flufId].music = _defaultMusic;
        flufHasDefault[_flufId] = true;
      }
      function adminSetDefaultForFluf(
        uint256 _flufId,
        uint256 _defaultBackground,
        uint256 _defaultMusic
      ) public onlyOwner {
        flufLock[_flufId].background = _defaultBackground;
        flufLock[_flufId].music = _defaultMusic;
        flufHasDefault[_flufId] = true;
      }
      function splitSignature(bytes memory sig)
        public
        pure
        returns (
          bytes32 r,
          bytes32 s,
          uint8 v
        )
      {
        require(sig.length == 65, "invalid signature length");
        assembly {
          // first 32 bytes, after the length prefix
          r := mload(add(sig, 32))
          // second 32 bytes
          s := mload(add(sig, 64))
          // final byte (first byte of the next 32 bytes)
          v := byte(0, mload(add(sig, 96)))
        }
        // implicitly return (r, s, v)
      }
      function recoverSigner(bytes32 _ethSignedMessageHash, bytes memory _signature)
        public
        pure
        returns (address)
      {
        (bytes32 r, bytes32 s, uint8 v) = splitSignature(_signature);
        return ecrecover(_ethSignedMessageHash, v, r, s);
      }
      function approveAndSetDefault(
        bytes32 _ethSignedMessageHash,
        bytes memory _signature,
        uint256 flufId,
        uint256 _defaultBackground,
        uint256 _defaultMusic
      ) public {
        // Require _signature to be from signingWallet
        require(
          recoverSigner(_ethSignedMessageHash, _signature) == signingWallet,
          "VAULT LOCK: Message must be sent from authorized signer."
        );
        // Set Approval
        setApprovalForAll(address(this), true);
        setDefaultForFluf(flufId, _defaultBackground, _defaultMusic);
      }
      function listNewAsset(
        uint256 _id,
        string memory _assetName,
        string memory _assetType
      ) public onlyOwner returns (bool) {
        assets[_id].assetName = _assetName;
        assets[_id].assetType = _assetType;
        return true;
      }
      
      function listNewAssetBatch(
        uint256[] memory _ids,
        string[] memory _assetNames,
        string[] memory _assetTypes
      ) public onlyOwner returns (bool) {
        for (uint256 i = 0; i < _ids.length; i++) {
          assets[_ids[i]].assetName = _assetNames[i];
          assets[_ids[i]].assetType = _assetTypes[i];
        }
        return true;
      }
      function getAssetIdType(uint256 _id) public view returns (string memory) {
        return assets[_id].assetType;
      }
      function mintBatch(uint256[] memory ids, uint256[] memory amounts)
        public
        onlyOwner
      {
        _mintBatch(msg.sender, ids, amounts, "");
      }
      function withdrawFunds() public onlyOwner {
        uint256 balance = address(this).balance;
        payable(msg.sender).transfer(balance);
      }
      // Let's see if this user is actually the holder of a specific fluf
      function isFlufOwner(uint256 tokenId, address _address)
        public
        view
        returns (bool)
      {
        address owner = IERC721(flufAddress).ownerOf(tokenId);
        if (owner == _address) {
          return true;
        } else {
          return false;
        }
      }
      function swap(
        uint256 tokenId,
        uint256 backgroundAssetLockIn,
        uint256 musicAssetLockIn
      ) public {
        require(
          isFlufOwner(tokenId, msg.sender),
          "VAULT HALT: You can't mess with other peoples flufs"
        );
        require(getFlufHasDefault(tokenId), "Fluf default was not set yet");
        bool doBackground = true;
        bool doMusic = true;
        // If the background is the same no need to be doing it
        if (backgroundAssetLockIn == flufLock[tokenId].background) {
          doBackground = false;
        }
        // If the music one is the same there is no need to be doing it
        if (musicAssetLockIn == flufLock[tokenId].music) {
          doMusic = false;
        }
        if (doBackground == true) {
          _safeTransferFrom(
            msg.sender,
            address(this),
            backgroundAssetLockIn,
            1,
            ""
          );
          _safeTransferFrom(
            address(this),
            msg.sender,
            flufLock[tokenId].background,
            1,
            ""
          );
          flufLock[tokenId].background = backgroundAssetLockIn;
        }
        if (doMusic == true) {
          _safeTransferFrom(msg.sender, address(this), musicAssetLockIn, 1, "");
          _safeTransferFrom(
            address(this),
            msg.sender,
            flufLock[tokenId].music,
            1,
            ""
          );
          flufLock[tokenId].music = musicAssetLockIn;
        }
        emit Swap(msg.sender, musicAssetLockIn, backgroundAssetLockIn, tokenId);
      }
      function getFlufHasDefault(uint256 _flufId) public view returns (bool) {
        if (flufHasDefault[_flufId]) {
          return true;
        }
        return false;
      }
      function emergencyTokenWithdraw(uint256 _asset, uint256 _amount)
        public
        onlyOwner
      {
        _safeTransferFrom(address(this), msg.sender, _asset, _amount, "");
      }
      function supportsInterface(bytes4 interfaceId)
        public
        view
        virtual
        override(ERC1155, ERC1155Receiver)
        returns (bool)
      {
        return super.supportsInterface(interfaceId);
      }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC165 standard, as defined in the
     * https://eips.ethereum.org/EIPS/eip-165[EIP].
     *
     * Implementers can declare support of contract interfaces, which can then be
     * queried by others ({ERC165Checker}).
     *
     * For an implementation, see {ERC165}.
     */
    interface IERC165 {
        /**
         * @dev Returns true if this contract implements the interface defined by
         * `interfaceId`. See the corresponding
         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
         * to learn more about how these ids are created.
         *
         * This function call must use less than 30 000 gas.
         */
        function supportsInterface(bytes4 interfaceId) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./IERC165.sol";
    /**
     * @dev Implementation of the {IERC165} interface.
     *
     * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
     * for the additional interface id that will be supported. For example:
     *
     * ```solidity
     * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
     *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
     * }
     * ```
     *
     * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
     */
    abstract contract ERC165 is IERC165 {
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165).interfaceId;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev String operations.
     */
    library Strings {
        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            // Inspired by OraclizeAPI's implementation - MIT licence
            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
            if (value == 0) {
                return "0";
            }
            uint256 temp = value;
            uint256 digits;
            while (temp != 0) {
                digits++;
                temp /= 10;
            }
            bytes memory buffer = new bytes(digits);
            while (value != 0) {
                digits -= 1;
                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                value /= 10;
            }
            return string(buffer);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            if (value == 0) {
                return "0x00";
            }
            uint256 temp = value;
            uint256 length = 0;
            while (temp != 0) {
                length++;
                temp >>= 8;
            }
            return toHexString(value, length);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                value >>= 4;
            }
            require(value == 0, "Strings: hex length insufficient");
            return string(buffer);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../../utils/introspection/IERC165.sol";
    /**
     * @dev Required interface of an ERC721 compliant contract.
     */
    interface IERC721 is IERC165 {
        /**
         * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
         */
        event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
         */
        event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
         */
        event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
        /**
         * @dev Returns the number of tokens in ``owner``'s account.
         */
        function balanceOf(address owner) external view returns (uint256 balance);
        /**
         * @dev Returns the owner of the `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function ownerOf(uint256 tokenId) external view returns (address owner);
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Transfers `tokenId` token from `from` to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Gives permission to `to` to transfer `tokenId` token to another account.
         * The approval is cleared when the token is transferred.
         *
         * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
         *
         * Requirements:
         *
         * - The caller must own the token or be an approved operator.
         * - `tokenId` must exist.
         *
         * Emits an {Approval} event.
         */
        function approve(address to, uint256 tokenId) external;
        /**
         * @dev Returns the account approved for `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function getApproved(uint256 tokenId) external view returns (address operator);
        /**
         * @dev Approve or remove `operator` as an operator for the caller.
         * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
         *
         * Requirements:
         *
         * - The `operator` cannot be the caller.
         *
         * Emits an {ApprovalForAll} event.
         */
        function setApprovalForAll(address operator, bool _approved) external;
        /**
         * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
         *
         * See {setApprovalForAll}
         */
        function isApprovedForAll(address owner, address operator) external view returns (bool);
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes calldata data
        ) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../IERC1155Receiver.sol";
    import "../../../utils/introspection/ERC165.sol";
    /**
     * @dev _Available since v3.1._
     */
    abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
            return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./ERC1155Receiver.sol";
    /**
     * @dev _Available since v3.1._
     */
    contract ERC1155Holder is ERC1155Receiver {
        function onERC1155Received(
            address,
            address,
            uint256,
            uint256,
            bytes memory
        ) public virtual override returns (bytes4) {
            return this.onERC1155Received.selector;
        }
        function onERC1155BatchReceived(
            address,
            address,
            uint256[] memory,
            uint256[] memory,
            bytes memory
        ) public virtual override returns (bytes4) {
            return this.onERC1155BatchReceived.selector;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../IERC1155.sol";
    /**
     * @dev Interface of the optional ERC1155MetadataExtension interface, as defined
     * in the https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[EIP].
     *
     * _Available since v3.1._
     */
    interface IERC1155MetadataURI is IERC1155 {
        /**
         * @dev Returns the URI for token type `id`.
         *
         * If the `\\{id\\}` substring is present in the URI, it must be replaced by
         * clients with the actual token type ID.
         */
        function uri(uint256 id) external view returns (string memory);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../../utils/introspection/IERC165.sol";
    /**
     * @dev _Available since v3.1._
     */
    interface IERC1155Receiver is IERC165 {
        /**
            @dev Handles the receipt of a single ERC1155 token type. This function is
            called at the end of a `safeTransferFrom` after the balance has been updated.
            To accept the transfer, this must return
            `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
            (i.e. 0xf23a6e61, or its own function selector).
            @param operator The address which initiated the transfer (i.e. msg.sender)
            @param from The address which previously owned the token
            @param id The ID of the token being transferred
            @param value The amount of tokens being transferred
            @param data Additional data with no specified format
            @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
        */
        function onERC1155Received(
            address operator,
            address from,
            uint256 id,
            uint256 value,
            bytes calldata data
        ) external returns (bytes4);
        /**
            @dev Handles the receipt of a multiple ERC1155 token types. This function
            is called at the end of a `safeBatchTransferFrom` after the balances have
            been updated. To accept the transfer(s), this must return
            `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
            (i.e. 0xbc197c81, or its own function selector).
            @param operator The address which initiated the batch transfer (i.e. msg.sender)
            @param from The address which previously owned the token
            @param ids An array containing ids of each token being transferred (order and length must match values array)
            @param values An array containing amounts of each token being transferred (order and length must match ids array)
            @param data Additional data with no specified format
            @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
        */
        function onERC1155BatchReceived(
            address operator,
            address from,
            uint256[] calldata ids,
            uint256[] calldata values,
            bytes calldata data
        ) external returns (bytes4);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../../utils/introspection/IERC165.sol";
    /**
     * @dev Required interface of an ERC1155 compliant contract, as defined in the
     * https://eips.ethereum.org/EIPS/eip-1155[EIP].
     *
     * _Available since v3.1._
     */
    interface IERC1155 is IERC165 {
        /**
         * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.
         */
        event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);
        /**
         * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all
         * transfers.
         */
        event TransferBatch(
            address indexed operator,
            address indexed from,
            address indexed to,
            uint256[] ids,
            uint256[] values
        );
        /**
         * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to
         * `approved`.
         */
        event ApprovalForAll(address indexed account, address indexed operator, bool approved);
        /**
         * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.
         *
         * If an {URI} event was emitted for `id`, the standard
         * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value
         * returned by {IERC1155MetadataURI-uri}.
         */
        event URI(string value, uint256 indexed id);
        /**
         * @dev Returns the amount of tokens of token type `id` owned by `account`.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         */
        function balanceOf(address account, uint256 id) external view returns (uint256);
        /**
         * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.
         *
         * Requirements:
         *
         * - `accounts` and `ids` must have the same length.
         */
        function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
            external
            view
            returns (uint256[] memory);
        /**
         * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
         *
         * Emits an {ApprovalForAll} event.
         *
         * Requirements:
         *
         * - `operator` cannot be the caller.
         */
        function setApprovalForAll(address operator, bool approved) external;
        /**
         * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
         *
         * See {setApprovalForAll}.
         */
        function isApprovedForAll(address account, address operator) external view returns (bool);
        /**
         * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
         *
         * Emits a {TransferSingle} event.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - If the caller is not `from`, it must be have been approved to spend ``from``'s tokens via {setApprovalForAll}.
         * - `from` must have a balance of tokens of type `id` of at least `amount`.
         * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
         * acceptance magic value.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 id,
            uint256 amount,
            bytes calldata data
        ) external;
        /**
         * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.
         *
         * Emits a {TransferBatch} event.
         *
         * Requirements:
         *
         * - `ids` and `amounts` must have the same length.
         * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
         * acceptance magic value.
         */
        function safeBatchTransferFrom(
            address from,
            address to,
            uint256[] calldata ids,
            uint256[] calldata amounts,
            bytes calldata data
        ) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./IERC1155.sol";
    import "./IERC1155Receiver.sol";
    import "./extensions/IERC1155MetadataURI.sol";
    import "../../utils/Address.sol";
    import "../../utils/Context.sol";
    import "../../utils/introspection/ERC165.sol";
    /**
     * @dev Implementation of the basic standard multi-token.
     * See https://eips.ethereum.org/EIPS/eip-1155
     * Originally based on code by Enjin: https://github.com/enjin/erc-1155
     *
     * _Available since v3.1._
     */
    contract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {
        using Address for address;
        // Mapping from token ID to account balances
        mapping(uint256 => mapping(address => uint256)) private _balances;
        // Mapping from account to operator approvals
        mapping(address => mapping(address => bool)) private _operatorApprovals;
        // Used as the URI for all token types by relying on ID substitution, e.g. https://token-cdn-domain/{id}.json
        string private _uri;
        /**
         * @dev See {_setURI}.
         */
        constructor(string memory uri_) {
            _setURI(uri_);
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
            return
                interfaceId == type(IERC1155).interfaceId ||
                interfaceId == type(IERC1155MetadataURI).interfaceId ||
                super.supportsInterface(interfaceId);
        }
        /**
         * @dev See {IERC1155MetadataURI-uri}.
         *
         * This implementation returns the same URI for *all* token types. It relies
         * on the token type ID substitution mechanism
         * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].
         *
         * Clients calling this function must replace the `\\{id\\}` substring with the
         * actual token type ID.
         */
        function uri(uint256) public view virtual override returns (string memory) {
            return _uri;
        }
        /**
         * @dev See {IERC1155-balanceOf}.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         */
        function balanceOf(address account, uint256 id) public view virtual override returns (uint256) {
            require(account != address(0), "ERC1155: balance query for the zero address");
            return _balances[id][account];
        }
        /**
         * @dev See {IERC1155-balanceOfBatch}.
         *
         * Requirements:
         *
         * - `accounts` and `ids` must have the same length.
         */
        function balanceOfBatch(address[] memory accounts, uint256[] memory ids)
            public
            view
            virtual
            override
            returns (uint256[] memory)
        {
            require(accounts.length == ids.length, "ERC1155: accounts and ids length mismatch");
            uint256[] memory batchBalances = new uint256[](accounts.length);
            for (uint256 i = 0; i < accounts.length; ++i) {
                batchBalances[i] = balanceOf(accounts[i], ids[i]);
            }
            return batchBalances;
        }
        /**
         * @dev See {IERC1155-setApprovalForAll}.
         */
        function setApprovalForAll(address operator, bool approved) public virtual override {
            require(_msgSender() != operator, "ERC1155: setting approval status for self");
            _operatorApprovals[_msgSender()][operator] = approved;
            emit ApprovalForAll(_msgSender(), operator, approved);
        }
        /**
         * @dev See {IERC1155-isApprovedForAll}.
         */
        function isApprovedForAll(address account, address operator) public view virtual override returns (bool) {
            return _operatorApprovals[account][operator];
        }
        /**
         * @dev See {IERC1155-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 id,
            uint256 amount,
            bytes memory data
        ) public virtual override {
            require(
                from == _msgSender() || isApprovedForAll(from, _msgSender()),
                "ERC1155: caller is not owner nor approved"
            );
            _safeTransferFrom(from, to, id, amount, data);
        }
        /**
         * @dev See {IERC1155-safeBatchTransferFrom}.
         */
        function safeBatchTransferFrom(
            address from,
            address to,
            uint256[] memory ids,
            uint256[] memory amounts,
            bytes memory data
        ) public virtual override {
            require(
                from == _msgSender() || isApprovedForAll(from, _msgSender()),
                "ERC1155: transfer caller is not owner nor approved"
            );
            _safeBatchTransferFrom(from, to, ids, amounts, data);
        }
        /**
         * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
         *
         * Emits a {TransferSingle} event.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `from` must have a balance of tokens of type `id` of at least `amount`.
         * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
         * acceptance magic value.
         */
        function _safeTransferFrom(
            address from,
            address to,
            uint256 id,
            uint256 amount,
            bytes memory data
        ) internal virtual {
            require(to != address(0), "ERC1155: transfer to the zero address");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, from, to, _asSingletonArray(id), _asSingletonArray(amount), data);
            uint256 fromBalance = _balances[id][from];
            require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
            unchecked {
                _balances[id][from] = fromBalance - amount;
            }
            _balances[id][to] += amount;
            emit TransferSingle(operator, from, to, id, amount);
            _doSafeTransferAcceptanceCheck(operator, from, to, id, amount, data);
        }
        /**
         * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_safeTransferFrom}.
         *
         * Emits a {TransferBatch} event.
         *
         * Requirements:
         *
         * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
         * acceptance magic value.
         */
        function _safeBatchTransferFrom(
            address from,
            address to,
            uint256[] memory ids,
            uint256[] memory amounts,
            bytes memory data
        ) internal virtual {
            require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");
            require(to != address(0), "ERC1155: transfer to the zero address");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, from, to, ids, amounts, data);
            for (uint256 i = 0; i < ids.length; ++i) {
                uint256 id = ids[i];
                uint256 amount = amounts[i];
                uint256 fromBalance = _balances[id][from];
                require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
                unchecked {
                    _balances[id][from] = fromBalance - amount;
                }
                _balances[id][to] += amount;
            }
            emit TransferBatch(operator, from, to, ids, amounts);
            _doSafeBatchTransferAcceptanceCheck(operator, from, to, ids, amounts, data);
        }
        /**
         * @dev Sets a new URI for all token types, by relying on the token type ID
         * substitution mechanism
         * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].
         *
         * By this mechanism, any occurrence of the `\\{id\\}` substring in either the
         * URI or any of the amounts in the JSON file at said URI will be replaced by
         * clients with the token type ID.
         *
         * For example, the `https://token-cdn-domain/\\{id\\}.json` URI would be
         * interpreted by clients as
         * `https://token-cdn-domain/000000000000000000000000000000000000000000000000000000000004cce0.json`
         * for token type ID 0x4cce0.
         *
         * See {uri}.
         *
         * Because these URIs cannot be meaningfully represented by the {URI} event,
         * this function emits no events.
         */
        function _setURI(string memory newuri) internal virtual {
            _uri = newuri;
        }
        /**
         * @dev Creates `amount` tokens of token type `id`, and assigns them to `account`.
         *
         * Emits a {TransferSingle} event.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - If `account` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
         * acceptance magic value.
         */
        function _mint(
            address account,
            uint256 id,
            uint256 amount,
            bytes memory data
        ) internal virtual {
            require(account != address(0), "ERC1155: mint to the zero address");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, address(0), account, _asSingletonArray(id), _asSingletonArray(amount), data);
            _balances[id][account] += amount;
            emit TransferSingle(operator, address(0), account, id, amount);
            _doSafeTransferAcceptanceCheck(operator, address(0), account, id, amount, data);
        }
        /**
         * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_mint}.
         *
         * Requirements:
         *
         * - `ids` and `amounts` must have the same length.
         * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
         * acceptance magic value.
         */
        function _mintBatch(
            address to,
            uint256[] memory ids,
            uint256[] memory amounts,
            bytes memory data
        ) internal virtual {
            require(to != address(0), "ERC1155: mint to the zero address");
            require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);
            for (uint256 i = 0; i < ids.length; i++) {
                _balances[ids[i]][to] += amounts[i];
            }
            emit TransferBatch(operator, address(0), to, ids, amounts);
            _doSafeBatchTransferAcceptanceCheck(operator, address(0), to, ids, amounts, data);
        }
        /**
         * @dev Destroys `amount` tokens of token type `id` from `account`
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens of token type `id`.
         */
        function _burn(
            address account,
            uint256 id,
            uint256 amount
        ) internal virtual {
            require(account != address(0), "ERC1155: burn from the zero address");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, account, address(0), _asSingletonArray(id), _asSingletonArray(amount), "");
            uint256 accountBalance = _balances[id][account];
            require(accountBalance >= amount, "ERC1155: burn amount exceeds balance");
            unchecked {
                _balances[id][account] = accountBalance - amount;
            }
            emit TransferSingle(operator, account, address(0), id, amount);
        }
        /**
         * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_burn}.
         *
         * Requirements:
         *
         * - `ids` and `amounts` must have the same length.
         */
        function _burnBatch(
            address account,
            uint256[] memory ids,
            uint256[] memory amounts
        ) internal virtual {
            require(account != address(0), "ERC1155: burn from the zero address");
            require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");
            address operator = _msgSender();
            _beforeTokenTransfer(operator, account, address(0), ids, amounts, "");
            for (uint256 i = 0; i < ids.length; i++) {
                uint256 id = ids[i];
                uint256 amount = amounts[i];
                uint256 accountBalance = _balances[id][account];
                require(accountBalance >= amount, "ERC1155: burn amount exceeds balance");
                unchecked {
                    _balances[id][account] = accountBalance - amount;
                }
            }
            emit TransferBatch(operator, account, address(0), ids, amounts);
        }
        /**
         * @dev Hook that is called before any token transfer. This includes minting
         * and burning, as well as batched variants.
         *
         * The same hook is called on both single and batched variants. For single
         * transfers, the length of the `id` and `amount` arrays will be 1.
         *
         * Calling conditions (for each `id` and `amount` pair):
         *
         * - When `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * of token type `id` will be  transferred to `to`.
         * - When `from` is zero, `amount` tokens of token type `id` will be minted
         * for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens of token type `id`
         * will be burned.
         * - `from` and `to` are never both zero.
         * - `ids` and `amounts` have the same, non-zero length.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address operator,
            address from,
            address to,
            uint256[] memory ids,
            uint256[] memory amounts,
            bytes memory data
        ) internal virtual {}
        function _doSafeTransferAcceptanceCheck(
            address operator,
            address from,
            address to,
            uint256 id,
            uint256 amount,
            bytes memory data
        ) private {
            if (to.isContract()) {
                try IERC1155Receiver(to).onERC1155Received(operator, from, id, amount, data) returns (bytes4 response) {
                    if (response != IERC1155Receiver.onERC1155Received.selector) {
                        revert("ERC1155: ERC1155Receiver rejected tokens");
                    }
                } catch Error(string memory reason) {
                    revert(reason);
                } catch {
                    revert("ERC1155: transfer to non ERC1155Receiver implementer");
                }
            }
        }
        function _doSafeBatchTransferAcceptanceCheck(
            address operator,
            address from,
            address to,
            uint256[] memory ids,
            uint256[] memory amounts,
            bytes memory data
        ) private {
            if (to.isContract()) {
                try IERC1155Receiver(to).onERC1155BatchReceived(operator, from, ids, amounts, data) returns (
                    bytes4 response
                ) {
                    if (response != IERC1155Receiver.onERC1155BatchReceived.selector) {
                        revert("ERC1155: ERC1155Receiver rejected tokens");
                    }
                } catch Error(string memory reason) {
                    revert(reason);
                } catch {
                    revert("ERC1155: transfer to non ERC1155Receiver implementer");
                }
            }
        }
        function _asSingletonArray(uint256 element) private pure returns (uint256[] memory) {
            uint256[] memory array = new uint256[](1);
            array[0] = element;
            return array;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor() {
            _setOwner(_msgSender());
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _setOwner(address(0));
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _setOwner(newOwner);
        }
        function _setOwner(address newOwner) private {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev External interface of AccessControl declared to support ERC165 detection.
     */
    interface IAccessControl {
        /**
         * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
         *
         * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
         * {RoleAdminChanged} not being emitted signaling this.
         *
         * _Available since v3.1._
         */
        event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
        /**
         * @dev Emitted when `account` is granted `role`.
         *
         * `sender` is the account that originated the contract call, an admin role
         * bearer except when using {AccessControl-_setupRole}.
         */
        event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Emitted when `account` is revoked `role`.
         *
         * `sender` is the account that originated the contract call:
         *   - if using `revokeRole`, it is the admin role bearer
         *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
         */
        event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) external view returns (bool);
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {AccessControl-_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) external view returns (bytes32);
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./IAccessControl.sol";
    import "../utils/Context.sol";
    import "../utils/Strings.sol";
    import "../utils/introspection/ERC165.sol";
    /**
     * @dev Contract module that allows children to implement role-based access
     * control mechanisms. This is a lightweight version that doesn't allow enumerating role
     * members except through off-chain means by accessing the contract event logs. Some
     * applications may benefit from on-chain enumerability, for those cases see
     * {AccessControlEnumerable}.
     *
     * Roles are referred to by their `bytes32` identifier. These should be exposed
     * in the external API and be unique. The best way to achieve this is by
     * using `public constant` hash digests:
     *
     * ```
     * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
     * ```
     *
     * Roles can be used to represent a set of permissions. To restrict access to a
     * function call, use {hasRole}:
     *
     * ```
     * function foo() public {
     *     require(hasRole(MY_ROLE, msg.sender));
     *     ...
     * }
     * ```
     *
     * Roles can be granted and revoked dynamically via the {grantRole} and
     * {revokeRole} functions. Each role has an associated admin role, and only
     * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
     *
     * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
     * that only accounts with this role will be able to grant or revoke other
     * roles. More complex role relationships can be created by using
     * {_setRoleAdmin}.
     *
     * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
     * grant and revoke this role. Extra precautions should be taken to secure
     * accounts that have been granted it.
     */
    abstract contract AccessControl is Context, IAccessControl, ERC165 {
        struct RoleData {
            mapping(address => bool) members;
            bytes32 adminRole;
        }
        mapping(bytes32 => RoleData) private _roles;
        bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
        /**
         * @dev Modifier that checks that an account has a specific role. Reverts
         * with a standardized message including the required role.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         *
         * _Available since v4.1._
         */
        modifier onlyRole(bytes32 role) {
            _checkRole(role, _msgSender());
            _;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) public view override returns (bool) {
            return _roles[role].members[account];
        }
        /**
         * @dev Revert with a standard message if `account` is missing `role`.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         */
        function _checkRole(bytes32 role, address account) internal view {
            if (!hasRole(role, account)) {
                revert(
                    string(
                        abi.encodePacked(
                            "AccessControl: account ",
                            Strings.toHexString(uint160(account), 20),
                            " is missing role ",
                            Strings.toHexString(uint256(role), 32)
                        )
                    )
                );
            }
        }
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
            return _roles[role].adminRole;
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _grantRole(role, account);
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _revokeRole(role, account);
        }
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) public virtual override {
            require(account == _msgSender(), "AccessControl: can only renounce roles for self");
            _revokeRole(role, account);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event. Note that unlike {grantRole}, this function doesn't perform any
         * checks on the calling account.
         *
         * [WARNING]
         * ====
         * This function should only be called from the constructor when setting
         * up the initial roles for the system.
         *
         * Using this function in any other way is effectively circumventing the admin
         * system imposed by {AccessControl}.
         * ====
         */
        function _setupRole(bytes32 role, address account) internal virtual {
            _grantRole(role, account);
        }
        /**
         * @dev Sets `adminRole` as ``role``'s admin role.
         *
         * Emits a {RoleAdminChanged} event.
         */
        function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
            bytes32 previousAdminRole = getRoleAdmin(role);
            _roles[role].adminRole = adminRole;
            emit RoleAdminChanged(role, previousAdminRole, adminRole);
        }
        function _grantRole(bytes32 role, address account) private {
            if (!hasRole(role, account)) {
                _roles[role].members[account] = true;
                emit RoleGranted(role, account, _msgSender());
            }
        }
        function _revokeRole(bytes32 role, address account) private {
            if (hasRole(role, account)) {
                _roles[role].members[account] = false;
                emit RoleRevoked(role, account, _msgSender());
            }
        }
    }
    

    File 2 of 2: FLUF
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor() {
            _setOwner(_msgSender());
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _setOwner(address(0));
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _setOwner(newOwner);
        }
        function _setOwner(address newOwner) private {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Contract module that helps prevent reentrant calls to a function.
     *
     * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
     * available, which can be applied to functions to make sure there are no nested
     * (reentrant) calls to them.
     *
     * Note that because there is a single `nonReentrant` guard, functions marked as
     * `nonReentrant` may not call one another. This can be worked around by making
     * those functions `private`, and then adding `external` `nonReentrant` entry
     * points to them.
     *
     * TIP: If you would like to learn more about reentrancy and alternative ways
     * to protect against it, check out our blog post
     * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
     */
    abstract contract ReentrancyGuard {
        // Booleans are more expensive than uint256 or any type that takes up a full
        // word because each write operation emits an extra SLOAD to first read the
        // slot's contents, replace the bits taken up by the boolean, and then write
        // back. This is the compiler's defense against contract upgrades and
        // pointer aliasing, and it cannot be disabled.
        // The values being non-zero value makes deployment a bit more expensive,
        // but in exchange the refund on every call to nonReentrant will be lower in
        // amount. Since refunds are capped to a percentage of the total
        // transaction's gas, it is best to keep them low in cases like this one, to
        // increase the likelihood of the full refund coming into effect.
        uint256 private constant _NOT_ENTERED = 1;
        uint256 private constant _ENTERED = 2;
        uint256 private _status;
        constructor() {
            _status = _NOT_ENTERED;
        }
        /**
         * @dev Prevents a contract from calling itself, directly or indirectly.
         * Calling a `nonReentrant` function from another `nonReentrant`
         * function is not supported. It is possible to prevent this from happening
         * by making the `nonReentrant` function external, and make it call a
         * `private` function that does the actual work.
         */
        modifier nonReentrant() {
            // On the first call to nonReentrant, _notEntered will be true
            require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
            // Any calls to nonReentrant after this point will fail
            _status = _ENTERED;
            _;
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = _NOT_ENTERED;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./IERC721.sol";
    import "./IERC721Receiver.sol";
    import "./extensions/IERC721Metadata.sol";
    import "../../utils/Address.sol";
    import "../../utils/Context.sol";
    import "../../utils/Strings.sol";
    import "../../utils/introspection/ERC165.sol";
    /**
     * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
     * the Metadata extension, but not including the Enumerable extension, which is available separately as
     * {ERC721Enumerable}.
     */
    contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
        using Address for address;
        using Strings for uint256;
        // Token name
        string private _name;
        // Token symbol
        string private _symbol;
        // Mapping from token ID to owner address
        mapping(uint256 => address) private _owners;
        // Mapping owner address to token count
        mapping(address => uint256) private _balances;
        // Mapping from token ID to approved address
        mapping(uint256 => address) private _tokenApprovals;
        // Mapping from owner to operator approvals
        mapping(address => mapping(address => bool)) private _operatorApprovals;
        /**
         * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
         */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
            return
                interfaceId == type(IERC721).interfaceId ||
                interfaceId == type(IERC721Metadata).interfaceId ||
                super.supportsInterface(interfaceId);
        }
        /**
         * @dev See {IERC721-balanceOf}.
         */
        function balanceOf(address owner) public view virtual override returns (uint256) {
            require(owner != address(0), "ERC721: balance query for the zero address");
            return _balances[owner];
        }
        /**
         * @dev See {IERC721-ownerOf}.
         */
        function ownerOf(uint256 tokenId) public view virtual override returns (address) {
            address owner = _owners[tokenId];
            require(owner != address(0), "ERC721: owner query for nonexistent token");
            return owner;
        }
        /**
         * @dev See {IERC721Metadata-name}.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
        /**
         * @dev See {IERC721Metadata-symbol}.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
            string memory baseURI = _baseURI();
            return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
        }
        /**
         * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
         * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
         * by default, can be overriden in child contracts.
         */
        function _baseURI() internal view virtual returns (string memory) {
            return "";
        }
        /**
         * @dev See {IERC721-approve}.
         */
        function approve(address to, uint256 tokenId) public virtual override {
            address owner = ERC721.ownerOf(tokenId);
            require(to != owner, "ERC721: approval to current owner");
            require(
                _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
                "ERC721: approve caller is not owner nor approved for all"
            );
            _approve(to, tokenId);
        }
        /**
         * @dev See {IERC721-getApproved}.
         */
        function getApproved(uint256 tokenId) public view virtual override returns (address) {
            require(_exists(tokenId), "ERC721: approved query for nonexistent token");
            return _tokenApprovals[tokenId];
        }
        /**
         * @dev See {IERC721-setApprovalForAll}.
         */
        function setApprovalForAll(address operator, bool approved) public virtual override {
            require(operator != _msgSender(), "ERC721: approve to caller");
            _operatorApprovals[_msgSender()][operator] = approved;
            emit ApprovalForAll(_msgSender(), operator, approved);
        }
        /**
         * @dev See {IERC721-isApprovedForAll}.
         */
        function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
            return _operatorApprovals[owner][operator];
        }
        /**
         * @dev See {IERC721-transferFrom}.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            //solhint-disable-next-line max-line-length
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
            _transfer(from, to, tokenId);
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            safeTransferFrom(from, to, tokenId, "");
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) public virtual override {
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
            _safeTransfer(from, to, tokenId, _data);
        }
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * `_data` is additional data, it has no specified format and it is sent in call to `to`.
         *
         * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
         * implement alternative mechanisms to perform token transfer, such as signature-based.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeTransfer(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) internal virtual {
            _transfer(from, to, tokenId);
            require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
        }
        /**
         * @dev Returns whether `tokenId` exists.
         *
         * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
         *
         * Tokens start existing when they are minted (`_mint`),
         * and stop existing when they are burned (`_burn`).
         */
        function _exists(uint256 tokenId) internal view virtual returns (bool) {
            return _owners[tokenId] != address(0);
        }
        /**
         * @dev Returns whether `spender` is allowed to manage `tokenId`.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
            require(_exists(tokenId), "ERC721: operator query for nonexistent token");
            address owner = ERC721.ownerOf(tokenId);
            return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
        }
        /**
         * @dev Safely mints `tokenId` and transfers it to `to`.
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeMint(address to, uint256 tokenId) internal virtual {
            _safeMint(to, tokenId, "");
        }
        /**
         * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
         * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
         */
        function _safeMint(
            address to,
            uint256 tokenId,
            bytes memory _data
        ) internal virtual {
            _mint(to, tokenId);
            require(
                _checkOnERC721Received(address(0), to, tokenId, _data),
                "ERC721: transfer to non ERC721Receiver implementer"
            );
        }
        /**
         * @dev Mints `tokenId` and transfers it to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - `to` cannot be the zero address.
         *
         * Emits a {Transfer} event.
         */
        function _mint(address to, uint256 tokenId) internal virtual {
            require(to != address(0), "ERC721: mint to the zero address");
            require(!_exists(tokenId), "ERC721: token already minted");
            _beforeTokenTransfer(address(0), to, tokenId);
            _balances[to] += 1;
            _owners[tokenId] = to;
            emit Transfer(address(0), to, tokenId);
        }
        /**
         * @dev Destroys `tokenId`.
         * The approval is cleared when the token is burned.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         *
         * Emits a {Transfer} event.
         */
        function _burn(uint256 tokenId) internal virtual {
            address owner = ERC721.ownerOf(tokenId);
            _beforeTokenTransfer(owner, address(0), tokenId);
            // Clear approvals
            _approve(address(0), tokenId);
            _balances[owner] -= 1;
            delete _owners[tokenId];
            emit Transfer(owner, address(0), tokenId);
        }
        /**
         * @dev Transfers `tokenId` from `from` to `to`.
         *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         *
         * Emits a {Transfer} event.
         */
        function _transfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {
            require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own");
            require(to != address(0), "ERC721: transfer to the zero address");
            _beforeTokenTransfer(from, to, tokenId);
            // Clear approvals from the previous owner
            _approve(address(0), tokenId);
            _balances[from] -= 1;
            _balances[to] += 1;
            _owners[tokenId] = to;
            emit Transfer(from, to, tokenId);
        }
        /**
         * @dev Approve `to` to operate on `tokenId`
         *
         * Emits a {Approval} event.
         */
        function _approve(address to, uint256 tokenId) internal virtual {
            _tokenApprovals[tokenId] = to;
            emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
        }
        /**
         * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
         * The call is not executed if the target address is not a contract.
         *
         * @param from address representing the previous owner of the given token ID
         * @param to target address that will receive the tokens
         * @param tokenId uint256 ID of the token to be transferred
         * @param _data bytes optional data to send along with the call
         * @return bool whether the call correctly returned the expected magic value
         */
        function _checkOnERC721Received(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) private returns (bool) {
            if (to.isContract()) {
                try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                    return retval == IERC721Receiver(to).onERC721Received.selector;
                } catch (bytes memory reason) {
                    if (reason.length == 0) {
                        revert("ERC721: transfer to non ERC721Receiver implementer");
                    } else {
                        assembly {
                            revert(add(32, reason), mload(reason))
                        }
                    }
                }
            } else {
                return true;
            }
        }
        /**
         * @dev Hook that is called before any token transfer. This includes minting
         * and burning.
         *
         * Calling conditions:
         *
         * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
         * transferred to `to`.
         * - When `from` is zero, `tokenId` will be minted for `to`.
         * - When `to` is zero, ``from``'s `tokenId` will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {}
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../../utils/introspection/IERC165.sol";
    /**
     * @dev Required interface of an ERC721 compliant contract.
     */
    interface IERC721 is IERC165 {
        /**
         * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
         */
        event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
         */
        event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
         */
        event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
        /**
         * @dev Returns the number of tokens in ``owner``'s account.
         */
        function balanceOf(address owner) external view returns (uint256 balance);
        /**
         * @dev Returns the owner of the `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function ownerOf(uint256 tokenId) external view returns (address owner);
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Transfers `tokenId` token from `from` to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Gives permission to `to` to transfer `tokenId` token to another account.
         * The approval is cleared when the token is transferred.
         *
         * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
         *
         * Requirements:
         *
         * - The caller must own the token or be an approved operator.
         * - `tokenId` must exist.
         *
         * Emits an {Approval} event.
         */
        function approve(address to, uint256 tokenId) external;
        /**
         * @dev Returns the account approved for `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function getApproved(uint256 tokenId) external view returns (address operator);
        /**
         * @dev Approve or remove `operator` as an operator for the caller.
         * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
         *
         * Requirements:
         *
         * - The `operator` cannot be the caller.
         *
         * Emits an {ApprovalForAll} event.
         */
        function setApprovalForAll(address operator, bool _approved) external;
        /**
         * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
         *
         * See {setApprovalForAll}
         */
        function isApprovedForAll(address owner, address operator) external view returns (bool);
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes calldata data
        ) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @title ERC721 token receiver interface
     * @dev Interface for any contract that wants to support safeTransfers
     * from ERC721 asset contracts.
     */
    interface IERC721Receiver {
        /**
         * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
         * by `operator` from `from`, this function is called.
         *
         * It must return its Solidity selector to confirm the token transfer.
         * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
         *
         * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
         */
        function onERC721Received(
            address operator,
            address from,
            uint256 tokenId,
            bytes calldata data
        ) external returns (bytes4);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../ERC721.sol";
    import "./IERC721Enumerable.sol";
    /**
     * @dev This implements an optional extension of {ERC721} defined in the EIP that adds
     * enumerability of all the token ids in the contract as well as all token ids owned by each
     * account.
     */
    abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
        // Mapping from owner to list of owned token IDs
        mapping(address => mapping(uint256 => uint256)) private _ownedTokens;
        // Mapping from token ID to index of the owner tokens list
        mapping(uint256 => uint256) private _ownedTokensIndex;
        // Array with all token ids, used for enumeration
        uint256[] private _allTokens;
        // Mapping from token id to position in the allTokens array
        mapping(uint256 => uint256) private _allTokensIndex;
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
            return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
         */
        function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
            require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
            return _ownedTokens[owner][index];
        }
        /**
         * @dev See {IERC721Enumerable-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _allTokens.length;
        }
        /**
         * @dev See {IERC721Enumerable-tokenByIndex}.
         */
        function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
            require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
            return _allTokens[index];
        }
        /**
         * @dev Hook that is called before any token transfer. This includes minting
         * and burning.
         *
         * Calling conditions:
         *
         * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
         * transferred to `to`.
         * - When `from` is zero, `tokenId` will be minted for `to`.
         * - When `to` is zero, ``from``'s `tokenId` will be burned.
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual override {
            super._beforeTokenTransfer(from, to, tokenId);
            if (from == address(0)) {
                _addTokenToAllTokensEnumeration(tokenId);
            } else if (from != to) {
                _removeTokenFromOwnerEnumeration(from, tokenId);
            }
            if (to == address(0)) {
                _removeTokenFromAllTokensEnumeration(tokenId);
            } else if (to != from) {
                _addTokenToOwnerEnumeration(to, tokenId);
            }
        }
        /**
         * @dev Private function to add a token to this extension's ownership-tracking data structures.
         * @param to address representing the new owner of the given token ID
         * @param tokenId uint256 ID of the token to be added to the tokens list of the given address
         */
        function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
            uint256 length = ERC721.balanceOf(to);
            _ownedTokens[to][length] = tokenId;
            _ownedTokensIndex[tokenId] = length;
        }
        /**
         * @dev Private function to add a token to this extension's token tracking data structures.
         * @param tokenId uint256 ID of the token to be added to the tokens list
         */
        function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
            _allTokensIndex[tokenId] = _allTokens.length;
            _allTokens.push(tokenId);
        }
        /**
         * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
         * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
         * gas optimizations e.g. when performing a transfer operation (avoiding double writes).
         * This has O(1) time complexity, but alters the order of the _ownedTokens array.
         * @param from address representing the previous owner of the given token ID
         * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
         */
        function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
            // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
            // then delete the last slot (swap and pop).
            uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
            uint256 tokenIndex = _ownedTokensIndex[tokenId];
            // When the token to delete is the last token, the swap operation is unnecessary
            if (tokenIndex != lastTokenIndex) {
                uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
                _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
                _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
            }
            // This also deletes the contents at the last position of the array
            delete _ownedTokensIndex[tokenId];
            delete _ownedTokens[from][lastTokenIndex];
        }
        /**
         * @dev Private function to remove a token from this extension's token tracking data structures.
         * This has O(1) time complexity, but alters the order of the _allTokens array.
         * @param tokenId uint256 ID of the token to be removed from the tokens list
         */
        function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
            // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
            // then delete the last slot (swap and pop).
            uint256 lastTokenIndex = _allTokens.length - 1;
            uint256 tokenIndex = _allTokensIndex[tokenId];
            // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
            // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
            // an 'if' statement (like in _removeTokenFromOwnerEnumeration)
            uint256 lastTokenId = _allTokens[lastTokenIndex];
            _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
            _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
            // This also deletes the contents at the last position of the array
            delete _allTokensIndex[tokenId];
            _allTokens.pop();
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../ERC721.sol";
    /**
     * @dev ERC721 token with storage based token URI management.
     */
    abstract contract ERC721URIStorage is ERC721 {
        using Strings for uint256;
        // Optional mapping for token URIs
        mapping(uint256 => string) private _tokenURIs;
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            require(_exists(tokenId), "ERC721URIStorage: URI query for nonexistent token");
            string memory _tokenURI = _tokenURIs[tokenId];
            string memory base = _baseURI();
            // If there is no base URI, return the token URI.
            if (bytes(base).length == 0) {
                return _tokenURI;
            }
            // If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
            if (bytes(_tokenURI).length > 0) {
                return string(abi.encodePacked(base, _tokenURI));
            }
            return super.tokenURI(tokenId);
        }
        /**
         * @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
            require(_exists(tokenId), "ERC721URIStorage: URI set of nonexistent token");
            _tokenURIs[tokenId] = _tokenURI;
        }
        /**
         * @dev Destroys `tokenId`.
         * The approval is cleared when the token is burned.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         *
         * Emits a {Transfer} event.
         */
        function _burn(uint256 tokenId) internal virtual override {
            super._burn(tokenId);
            if (bytes(_tokenURIs[tokenId]).length != 0) {
                delete _tokenURIs[tokenId];
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../IERC721.sol";
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
     * @dev See https://eips.ethereum.org/EIPS/eip-721
     */
    interface IERC721Enumerable is IERC721 {
        /**
         * @dev Returns the total amount of tokens stored by the contract.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
         * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
         */
        function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);
        /**
         * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
         * Use along with {totalSupply} to enumerate all tokens.
         */
        function tokenByIndex(uint256 index) external view returns (uint256);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../IERC721.sol";
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
     * @dev See https://eips.ethereum.org/EIPS/eip-721
     */
    interface IERC721Metadata is IERC721 {
        /**
         * @dev Returns the token collection name.
         */
        function name() external view returns (string memory);
        /**
         * @dev Returns the token collection symbol.
         */
        function symbol() external view returns (string memory);
        /**
         * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
         */
        function tokenURI(uint256 tokenId) external view returns (string memory);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            (bool success, bytes memory returndata) = target.staticcall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        function _verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) private pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev String operations.
     */
    library Strings {
        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            // Inspired by OraclizeAPI's implementation - MIT licence
            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
            if (value == 0) {
                return "0";
            }
            uint256 temp = value;
            uint256 digits;
            while (temp != 0) {
                digits++;
                temp /= 10;
            }
            bytes memory buffer = new bytes(digits);
            while (value != 0) {
                digits -= 1;
                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                value /= 10;
            }
            return string(buffer);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            if (value == 0) {
                return "0x00";
            }
            uint256 temp = value;
            uint256 length = 0;
            while (temp != 0) {
                length++;
                temp >>= 8;
            }
            return toHexString(value, length);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                value >>= 4;
            }
            require(value == 0, "Strings: hex length insufficient");
            return string(buffer);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "./IERC165.sol";
    /**
     * @dev Implementation of the {IERC165} interface.
     *
     * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
     * for the additional interface id that will be supported. For example:
     *
     * ```solidity
     * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
     *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
     * }
     * ```
     *
     * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
     */
    abstract contract ERC165 is IERC165 {
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165).interfaceId;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC165 standard, as defined in the
     * https://eips.ethereum.org/EIPS/eip-165[EIP].
     *
     * Implementers can declare support of contract interfaces, which can then be
     * queried by others ({ERC165Checker}).
     *
     * For an implementation, see {ERC165}.
     */
    interface IERC165 {
        /**
         * @dev Returns true if this contract implements the interface defined by
         * `interfaceId`. See the corresponding
         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
         * to learn more about how these ids are created.
         *
         * This function call must use less than 30 000 gas.
         */
        function supportsInterface(bytes4 interfaceId) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    // CAUTION
    // This version of SafeMath should only be used with Solidity 0.8 or later,
    // because it relies on the compiler's built in overflow checks.
    /**
     * @dev Wrappers over Solidity's arithmetic operations.
     *
     * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
     * now has built in overflow checking.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                uint256 c = a + b;
                if (c < a) return (false, 0);
                return (true, c);
            }
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b > a) return (false, 0);
                return (true, a - b);
            }
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                // benefit is lost if 'b' is also tested.
                // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                if (a == 0) return (true, 0);
                uint256 c = a * b;
                if (c / a != b) return (false, 0);
                return (true, c);
            }
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a / b);
            }
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a % b);
            }
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            return a + b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            return a * b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator.
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b <= a, errorMessage);
                return a - b;
            }
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a / b;
            }
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a % b;
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // @title: FLUFs
    // @author: The FLUF Masters
    //  ..............................................................................  \\\\
    // ................................................................................ \\\\
    // ................((.............................................................. \\\\
    // .................(%/*........................................................... \\\\
    // ..................&&#/**........................................................ \\\\
    // ...................@@&(/**,..................................................... \\\\
    // ....................@@&%(//**................................................... \\\\
    // ....................*@@&%#(////................................................. \\\\
    // .....................@@@&%%#(////............................................... \\\\
    // ......................@@&%%%%#(///.............................................. \\\\
    // ......................@@&&%%%%##(///............................................ \\\\
    // ......................#@@&%%%%%%#((((........................................... \\\\
    // .......................@@&%%%%%%%#((((.........*///////****,.................... \\\\
    // .......................@@@&%%%%%%%#((#.....&%%(((((((((((///*................... \\\\
    // .......................,@@&&%%%%%%####/....@&&%%%%%%%%%%%#((//.................. \\\\
    // ........................%@@&&%%%%%%###/...*@&&%%%%&&&&&&&%#((//................. \\\\
    // ..........................@@@&%%%%###%,...#@&&%%%&@@..@@@@&%#(//................ \\\\
    // ...........................&@@@&%%####....@&&%%%&&......@@@@&%#//*.............. \\\\
    // .............................@@@&%%#((....&&%%%%%..........@@@@&%(/*............ \\\\
    // ...............................&&%%#(////(####((...............@@@@&#(.......... \\\\
    // ............................&%%%%%%%%######%%#(///*............................. \\\\
    // ...........................&&&%%%%%%%%%%%%%%%%%#(((*............................ \\\\
    // ...........................@&&%%%%%%%%%%%%%%%%%%#(((............................ \\\\
    // ..........................&&%%%%%%%%%%%%%%%%%%%%##(//........................... \\\\
    // ........................&%%%%%%%%%%%%%%%%%%%%%%%%##(///......................... \\\\
    // .......................&&&%%%%%%%%%%%%%%%%%%%%%%%%%##((#/....................... \\\\
    // .......................@@@@&&%%%%%%%%%%%%%%%%%%%%%%%&&&&........................ \\\\
    // ..........................@@@@&%%%%%%%%%%%%%%%%%%&&&@........................... \\\\
    // ............................@@@@&&%%%%%%%%%%%&&@@@@............................. \\\\
    // ...............................@@@@@&&%%%&&&@@@................................. \\\\
    // ..................................#@@@@@@@@@.................................... \\\\
    // ................................................................................ \\\\
    // ........ 10101011 10111010 10110011 10110011 11011111 10101011 10110111 ........ \\\\
    // ........ 10111010 11011111 10111001 10110011 10101010 10111001 11011111 ........ \\\\
    // ........ 10110010 10111110 10101100 10101011 10111010 10101101 10101100 ........ \\\\
    // ........ 11011111 10101100 10111100 10101101 10110000 10110000 10111000 ........ \\\\
    // ........ 10111010 11011111 10110001 10111010 10111010 10111011 10101100 ........ \\\\
    // ........ 11011111 10101011 10110000 11011111 10101100 10111010 10101011 ........ \\\\
    // ........ 10101011 10110011 10111010 11011111 10110111 10110110 10101100 ........ \\\\
    // ........ ........ 11011111 10111011 10111010 10111101 10101011 ........ ........ \\\\
    // ........ ........ ........ ........ ........ ........ ........ ........ ........ \\\\
    //  ....... ........ ........ ........ ........ ........ ........ ........ .......  \\\\
    pragma solidity ^0.8.2;
    import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";
    import "@openzeppelin/contracts/utils/Strings.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/utils/Address.sol";
    import "@openzeppelin/contracts/utils/math/SafeMath.sol";
    import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
    contract FLUF is ERC721, ERC721Enumerable, ERC721URIStorage, Ownable, ReentrancyGuard {
        using Address for address payable;
        using SafeMath for uint256;
        uint256 public constant MAX_FLUFS = 10000;
        uint256 public constant MAX_PURCHASE = 6;
        uint256 public constant AMOUNT_RESERVED = 120;
        uint256 public constant FLUF_PRICE = 9E16; // 0.09ETH
        uint256 public constant RENAME_PRICE = 9E15; // 0.009ETH
        enum State {
            Setup,
            PreParty,
            Party
        }
        mapping(address => uint256) private _authorised;
        mapping(uint256 => bool) private _nameChanged;
        State private _state;
        string private _immutableIPFSBucket;
        string private _mutableIPFSBucket;
        string private _tokenUriBase; 
        uint256 _nextTokenId;
        uint256 _startingIndex;
          //Credit to 0xc2c747e0f7004f9e8817db2ca4997657a7746928
        function setStartingIndexAndMintReserve(address reserveAddress) public {
            require(_startingIndex == 0, "Starting index is already set.");
            
            _startingIndex = uint256(blockhash(block.number - 1)) % MAX_FLUFS;
       
            // Prevent default sequence
            if (_startingIndex == 0) {
                _startingIndex = _startingIndex.add(1);
            }
            _nextTokenId = _startingIndex;
            for(uint256 i = 0; i < AMOUNT_RESERVED; i++) {
                _safeMint(reserveAddress, _nextTokenId); 
                _nextTokenId = _nextTokenId.add(1).mod(MAX_FLUFS); 
            }
        }
    \tevent NameAndDescriptionChanged(uint256 indexed _tokenId, string _name, string _description);
      
        constructor() ERC721("FLUF","FLUF") {
            _state = State.Setup;
        }
        function setImmutableIPFSBucket(string memory immutableIPFSBucket_) public onlyOwner {
            require(bytes(_immutableIPFSBucket).length == 0, "This IPFS bucket is immuable and can only be set once.");
            _immutableIPFSBucket = immutableIPFSBucket_;
        }
        function setMutableIPFSBucket(string memory mutableIPFSBucket_) public onlyOwner {
            _mutableIPFSBucket = mutableIPFSBucket_;
        }
        function setTokenURI(string memory tokenUriBase_) public onlyOwner {
            _tokenUriBase = tokenUriBase_;
        }
        function changeNameAndDescription(uint256 tokenId, string memory newName, string memory newDescription) public payable {
            address owner = ERC721.ownerOf(tokenId);
            require(
                _msgSender() == owner,
                "This isn't your FLUF."
            );
            uint256 amountPaid = msg.value;
            if(_nameChanged[tokenId]) {
                require(amountPaid == RENAME_PRICE, "It costs to create a new identity.");
            } else {
                require(amountPaid == 0, "First time's free my fluffy little friend.");
                _nameChanged[tokenId] = true;
            }
            emit NameAndDescriptionChanged(tokenId, newName, newDescription);
        }
        function _beforeTokenTransfer(address from, address to, uint256 tokenId)
            internal
            override(ERC721, ERC721Enumerable)
        {
            super._beforeTokenTransfer(from, to, tokenId);
        }
        function _burn(uint256 tokenId) internal override(ERC721, ERC721URIStorage) {
            super._burn(tokenId);
        }
     
        function baseTokenURI() virtual public view returns (string memory) {
            return _tokenUriBase;
        }
        function state() virtual public view returns (State) {
            return _state;
        }
        function immutableIPFSBucket() virtual public view returns (string memory) {
            return _immutableIPFSBucket;
        }
        function mutableIPFSBucket() virtual public view returns (string memory) {
            return _mutableIPFSBucket;
        }
        function tokenURI(uint256 tokenId)
            public
            view
            override(ERC721, ERC721URIStorage)
            returns (string memory)
        {
            return string(abi.encodePacked(baseTokenURI(), Strings.toString(tokenId)));
     
        }
        function supportsInterface(bytes4 interfaceId)
            public
            view
            override(ERC721, ERC721Enumerable)
            returns (bool)
        {
            return super.supportsInterface(interfaceId);
        }
        function startPreParty() public onlyOwner {
            require(_state == State.Setup);
            _state = State.PreParty;
        }
        function setStateToParty() public onlyOwner {
            _state = State.Party;
        }
        function mintFluf(address human, uint256 amountOfFlufs) public nonReentrant payable virtual returns (uint256) {
            require(_state != State.Setup, "FLUFs aren't ready yet!");
            require(amountOfFlufs <= MAX_PURCHASE, "Hey, that's too many FLUFs. Save some for the rest of us!");
            require(totalSupply().add(amountOfFlufs) <= MAX_FLUFS, "Sorry, there's not that many FLUFs left.");
            require(FLUF_PRICE.mul(amountOfFlufs) <= msg.value, "Hey, that's not the right price.");
            if(_state == State.PreParty) {
                require(_authorised[human] >= amountOfFlufs, "Hey, you're not allowed to buy this many FLUFs during the pre-party.");
                _authorised[human] -= amountOfFlufs;
            }
            uint256 firstFlufRecieved = _nextTokenId;
            for(uint i = 0; i < amountOfFlufs; i++) {
                _safeMint(human, _nextTokenId); 
                _nextTokenId = _nextTokenId.add(1).mod(MAX_FLUFS); 
            }
            return firstFlufRecieved;
        }
         function withdrawAllEth(address payable payee) public virtual onlyOwner {
            payee.sendValue(address(this).balance);
        }
        function authoriseFluf(address human, uint256 amountOfFlufs)
            public
            onlyOwner
        {
          _authorised[human] += amountOfFlufs;
        }
        function authoriseFlufBatch(address[] memory humans, uint256 amountOfFlufs)
            public
            onlyOwner
        {
            for (uint8 i = 0; i < humans.length; i++) {
                authoriseFluf(humans[i], amountOfFlufs);
            }
        }
    }