ETH Price: $3,337.51 (-1.38%)
Gas: 23 Gwei

Contract Diff Checker

Contract Name:
RoyalFoolsHalloween

Contract Source Code:

File 1 of 1 : RoyalFoolsHalloween

// ██████╗░░█████╗░██╗░░░██╗░█████╗░██╗░░░░░███████╗░█████╗░░█████╗░██╗░░░░░░██████╗
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// ██║░░██║╚█████╔╝░░░██║░░░██║░░██║███████╗██║░░░░░╚█████╔╝╚█████╔╝███████╗██████╔╝
// ╚═╝░░╚═╝░╚════╝░░░░╚═╝░░░╚═╝░░╚═╝╚══════╝╚═╝░░░░░░╚════╝░░╚════╝░╚══════╝╚═════╝░
// SPDX-License-Identifier: MIT
//OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
   function _msgSender() internal view virtual returns(address) {
      return msg.sender;
   }

   function _msgData() internal view virtual returns(bytes calldata) {
      return msg.data;
   }
}


//OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;

/**
 * @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 module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
   address private _owner;

   event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

   /**
    * @dev Initializes the contract setting the deployer as the initial owner.
   */
   constructor() {
      _transferOwnership(_msgSender());
   }

   /**
    * @dev Returns the address of the current owner.
   */
   function owner() public view virtual returns (address) {
      return _owner;
   }

   /**
    * @dev Throws if called by any account other than the owner.
   */
   modifier onlyOwner() {
      require(owner() == _msgSender(), "Not an owner");
      _;
   }

   /**
    * @dev Leaves the contract without owner. It will not be possible to call
    * `onlyOwner` functions anymore. Can only be called by the current owner.
    * NOTE: Renouncing ownership will leave the contract without an owner,
    * thereby removing any functionality that is only available to the owner.
   */
   function renounceOwnership() public virtual onlyOwner {
      _transferOwnership(address(0));
   }

   /**
    * @dev Transfers ownership of the contract to a new account (`newOwner`).
    * Can only be called by the current owner.
   */
   function transferOwnership(address newOwner) public virtual onlyOwner {
      require(newOwner != address(0), "Ownable: new owner is the zero address");
      _transferOwnership(newOwner);
   }

   /**
    * @dev Transfers ownership of the contract to a new account (`newOwner`).
    * Internal function without access restriction.
   */
   function _transferOwnership(address newOwner) internal virtual {
      address oldOwner = _owner;
      _owner = newOwner;
      emit OwnershipTransferred(oldOwner, newOwner);
   }
}


// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {

        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);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}
//  .-. .-.  .--.  ,---.  ,---..-.   .-.                
//  | | | | / /\ \ | .-.\ | .-.\\ \_/ )/                
//  | `-' |/ /__\ \| |-' )| |-' )\   (_)                
//  | .-. ||  __  || |--' | |--'  ) (                   
//  | | |)|| |  |)|| |    | |     | |                   
//  /(  (_)|_|  (_)/(     /(     /(_|                   
// (__)           (__)   (__)   (__)                    
//      .---. ,---.   .---.   .---.  ,-. .-..-.   .-.   
//     ( .-._)| .-.\ / .-. ) / .-. ) | |/ /  \ \_/ )/   
//    (_) \   | |-' )| | |(_)| | |(_)| | /    \   (_)   
//    _  \ \  | |--' | | | | | | | | | | \     ) (      
//   ( `-'  ) | |    \ `-' / \ `-' / | |) \    | |      
//    `----'  /(      )---'   )---'  |((_)-'  /(_|      
//           (__)    (_)     (_)     (_)     (__)       
//                     ,--,  ,-.      .--.  ,-.         
//                   .' .')  | |     / /\ \ |(||\    /| 
//                   |  |(_) | |    / /__\ \(_)|(\  / | 
//                   \  \    | |    |  __  || |(_)\/  | 
//                    \  `-. | `--. | |  |)|| || \  / | 
//                     \____\|( __.'|_|  (_)`-'| |\/| | 
//                           (_)               '-'  '-' 

// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
pragma solidity ^0.8.1;

/**
 * @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
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 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 functionCallWithValue(target, data, 0, "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");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or 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 {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // 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
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}


// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}


// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}


// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;

/**
 * @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;
    }
}


// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 {
   /**
    * @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;
}


// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
pragma solidity ^0.8.0;

/**
 * @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);
}

//                     .. ...                                        
//                       .....                                        
//                      .....
//                     ........                                       
//                     ...... ///.((###.//////             
//               () .  ....***...//(((((##///(((**.       
//           ()..,///***.....(/,,//((((#*(((###((((((*/.               
//         .((////(((.#(/.(#((###((/(#((##((((###((((///           
//        ((/(SKAKUN/(##(( /(.#,,###(/((#((##(((#####(((((.            
//       .*(/#####((##,((.#/..  AVERA((##,,//(((#####*####*          
//      .((*(ANKH((((#/,(###( *.#####(,,... (*//(#####(((((*         
//     .//((#####(,((## (#.#,/((##(DAHLIN/,. ,*/((((###*((((,      
//     /*/(/#####(/((###.(##*(//(#METAVERSEM4STER(,. *//((_(((*       
//    **.((***.,*&%###/((/((./*.*/&&&%&&&&&*.**/,(#/(####//,/()   
//    *,/(/**,/*(KING'S FOOL(*.*,,** ./YA RISUU**//*#(#(((##()         
//    */(,(/*,*(,%&&&&&&%,/*/**/(.*%&&&&&&/*/ .##(##(((((//**)         
//    .((,#(//**(#*&&&&&%#(((  ##(((#####(/(/ *(####(((((///)
//    /#((((##(.*//.//(((#(((/((,##((#(   ##  ((###((/((///*          
//    .#(/(((####(/  (((###((##((###       , //(((//.///,/
//     ////#(((#####,(  (##, /#/            /(/////**//            
//       //,((,((#####.(#  ,           ##  .((//*/*               
//          .///*/((###*(((,//##/.     ,#(((((/                   
//                  ((((///((//(((((((((/     


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
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 `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}


// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.0;

contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    string private _name;

    string private _symbol;

    mapping(uint256 => address) private _owners;

    mapping(address => uint256) private _balances;

    mapping(uint256 => address) private _tokenApprovals;

    mapping(address => mapping(address => bool)) private _operatorApprovals;

    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: address zero is not a valid owner");
        return _balances[owner];
    }

    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _ownerOf(tokenId);
        require(owner != address(0), "ERC721: invalid token ID");
        return owner;
    }

    function name() public view virtual override returns (string memory) {
        return _name;
    }

    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        _requireMinted(tokenId);

        string memory baseURI = _baseURI();
        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
    }

    function _baseURI() internal view virtual returns (string memory) {
        return "";
    }

    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 token owner or approved for all"
        );

        _approve(to, tokenId);
    }

    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        _requireMinted(tokenId);

        return _tokenApprovals[tokenId];
    }

    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");

        _transfer(from, to, tokenId);
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory data
    ) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
        _safeTransfer(from, to, tokenId, data);
    }

    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");
    }

    function _ownerOf(uint256 tokenId) internal view virtual returns (address) {
        return _owners[tokenId];
    }

    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _ownerOf(tokenId) != address(0);
    }

    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
    }

    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    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"
        );
    }

    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);

        require(!_exists(tokenId), "ERC721: token already minted");

        unchecked {
            _balances[to] += 1;
        }

        _owners[tokenId] = to;

        emit Transfer(address(0), to, tokenId);

        _afterTokenTransfer(address(0), to, tokenId);
    }

    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

        _beforeTokenTransfer(owner, address(0), tokenId);

        owner = ERC721.ownerOf(tokenId);

        delete _tokenApprovals[tokenId];

        unchecked {
            _balances[owner] -= 1;
        }
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);

        _afterTokenTransfer(owner, address(0), tokenId);
    }

    function _transfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId);

        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");

        delete _tokenApprovals[tokenId];

        unchecked {
            _balances[from] -= 1;
            _balances[to] += 1;
        }
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId);
    }

    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

    function _setApprovalForAll(
        address owner,
        address operator,
        bool approved
    ) internal virtual {
        require(owner != operator, "ERC721: approve to caller");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    function _requireMinted(uint256 tokenId) internal view virtual {
        require(_exists(tokenId), "ERC721: invalid token ID");
    }

    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.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;
        }
    }

    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}

    function _afterTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}

    function _beforeConsecutiveTokenTransfer(
        address from,
        address to,
        uint256,
        uint96 size
    ) internal virtual {
        if (from != address(0)) {
            _balances[from] -= size;
        }
        if (to != address(0)) {
            _balances[to] += size;
        }
    }

    function _afterConsecutiveTokenTransfer(
        address,
        address,
        uint256,
        uint96
    ) internal virtual {}
}


interface IRoyalFools {
    function balanceOf(address owner) external view returns (uint256);
}

// ██░ ██  ▄▄▄      ██▓     ██▓     ▒███████  █     █░▓█████ ▓█████  ███▄    █
// ██░ ██ ▒████▄    ▓██▒    ▓██▒    ▒██▒  ██ ▓█░ █ ░█░▓█   ▀ ▓█   ▀  ██ ▀█   █
// ██▀▀██ ▒██  ▀█▄  ▒██░    ▒██░    ▒██░  ██ ▒█░ █ ░█ ▒███   ▒███   ▓██  ▀█ ██
// ▓█ ░██ ░██▄▄▄▄██ ▒██░    ▒██░    ▒██   ██ ░█░ █ ░█ ▒▓█  ▄ ▒▓█  ▄ ▓██▒  ▐▌██
// ▓█ ░██ ▒▓█   ▓██▒░██████▒░██████▒░ ████▓▒ ░░██▒██▓ ░▒████▒░▒████▒▒██░   ▓██
// ▒  ░▒ ▒ ▒   ▓▒█ ░ ▒░▓  ░░ ▒░▓  ░░ ▒░▒░▒░ ░ ▓░▒ ▒  ░░ ▒░ ░░░ ▒░ ░░ ▒░   ▒ ▒ 
// ▒  ▒░ ░  ▒   ▒▒ ░░ ░ ▒  ░░ ░ ▒  ░  ░ ▒ ▒░  ▒ ░ ░  ░ ░  ░ ░ ░  ░░ ░░   ░ ▒░
// ░  ░░ ░  ░   ▒     ░ ░    ░ ░   ░ ░ ░ ▒    ░   ░    ░    ░     ░   ░ ░ 
// ░  ░  ░    ░  ░   ░  ░    ░  ░    ░ ░      ░       ░  ░   ░  ░         ░ 


pragma solidity ^0.8.17;

contract RoyalFoolsHalloween is ERC721, Ownable {
   using Counters for Counters.Counter;
   using Strings for uint256;

   Counters.Counter private supply;

   string public baseTokenURI;
   string public baseExtension;
   uint256 public maxElements;

   IRoyalFools private token;

   bool public isPaused;

   mapping(address => uint256) avaliableClaims;
   mapping(address => bool) isClaimer;

   error Soldout();
   error EmptyBalance();
   error AlreadyClaimed();
   error ContractIsPaused();

   constructor(
       string memory baseURI,
       string memory _baseExtension,
       uint256 _maxElements) ERC721("RoyalFoolsHalloween", "RFH") {

           supply.increment();
           setBaseURI(baseURI);

           baseExtension = _baseExtension;
           maxElements = _maxElements;
           token = IRoyalFools(0xCF3bc939f9B2487092936F21cC0757b2b523B7aA);
    }

    modifier claimIsOpen() {
        if (isPaused == false) {
            revert ContractIsPaused();
        }
        if (totalSupply() > maxElements) {
            revert Soldout();
        }
        _;
    }

    function totalSupply() public view returns (uint256) {
        return supply.current();
    }

    function claim() public claimIsOpen {
        address wallet = _msgSender();
        uint256 tokenId = totalSupply();
        uint256 balance = token.balanceOf(wallet);

        require(balance > 0, "Empty balance");

        if (!isClaimer[wallet]) {
            avaliableClaims[wallet] = balance;
            isClaimer[wallet] = true;
        }

        require(avaliableClaims[wallet] > 0, "All claimed");

        _safeMint(wallet, tokenId);
        supply.increment();
        avaliableClaims[wallet] -= 1;
    }

    function burn(uint256 tokenId) public {
        require(_isApprovedOrOwner(msg.sender, tokenId), "Not approved or owner");
        _burn(tokenId);
    }

    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "URI for nonexistent tokenId");

        string memory baseURI = _baseURI();

        return bytes(baseURI).length > 0
        ? string(abi.encodePacked(baseURI, tokenId.toString(), baseExtension))
        : "";
    }

    function _baseURI() internal view override returns (string memory) {
        return baseTokenURI;
    }

    function setBaseExtension(string memory _newExtension) public onlyOwner {
        baseExtension = _newExtension;
    }

    function setBaseURI(string memory baseURI) public onlyOwner {
        baseTokenURI = baseURI;
    }

    function setMaxElements(uint256 _newAmount) public onlyOwner {
        maxElements = _newAmount;
    }

    function setPause(bool _newState) public onlyOwner {
        isPaused = _newState;
    }

    function uncheckedIncrement(uint256 i) internal pure returns (uint256) {
        unchecked {
            i++;
        }
        return i;
    }
}

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