// File: contracts/FlashingLights.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "./access/AdminControl.sol";
import "./core/IERC721CreatorCore.sol";
import "./extensions/ICreatorExtensionTokenURI.sol";

import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";

/**
 * As I recall, I know you love to show off
 * But I never thought that you would take it this far
 * What do I know?
 */
contract FlashingLights is AdminControl, ICreatorExtensionTokenURI {

    using Strings for uint256;

    address private _creator;
    uint private _tokenId;
    string public _script;
    string private _name;
    string private _description;
    string private _attributes;
    string[2] private _previews;

    constructor(address creator) {
        _creator = creator;
    }

    function supportsInterface(bytes4 interfaceId) public view virtual override(AdminControl, IERC165) returns (bool) {
        return interfaceId == type(ICreatorExtensionTokenURI).interfaceId || AdminControl.supportsInterface(interfaceId) || super.supportsInterface(interfaceId);
    }

    function mint() public adminRequired {
        require(_tokenId == 0, 'Token already minted');
        _tokenId = IERC721CreatorCore(_creator).mintExtension(msg.sender);
    }

    function setScript(string memory script) public adminRequired {
      _script = script;
    }

    function setName(string memory name) public adminRequired {
      _name = name;
    }

    function setDescription(string memory description) public adminRequired {
      _description = description;
    }

    function setAttributes(string memory attributes) public adminRequired {
      _attributes = attributes;
    }

    function setPreviews(string memory imagePreview, string memory videoPreview) public {
      require(IERC721(_creator).ownerOf(_tokenId) == msg.sender || isAdmin(msg.sender), "Only owner or admin can change.");
      _previews[0] = imagePreview;
      _previews[1] = videoPreview;
    }

    function tokenURI(address creator, uint256 tokenId) external view override returns (string memory) {
        require(creator == _creator && tokenId == _tokenId, "Invalid token");
        return string(abi.encodePacked('data:application/json;utf8,',
        '{"name":"',
        _name,
        '","created_by":"yung wknd","description":"',
        _description,
        '","image":"',
        _previews[0],
        '","image_url":"',
        _previews[0],
        '","animation":"',
        _previews[1],
        '","animation_url":"',
        _previews[1],
        '","attributes":[',
        _attributes,
        ']}'));
    }
}

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol



// 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;
    }
}

// File: @openzeppelin/contracts/utils/Strings.sol



// 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);
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol



// 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);
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;
}

// File: contracts/extensions/ICreatorExtensionTokenURI.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/utils/introspection/IERC165.sol";

/**
 * @dev Implement this if you want your extension to have overloadable URI's
 */
interface ICreatorExtensionTokenURI is IERC165 {

    /**
     * Get the uri for a given creator/tokenId
     */
    function tokenURI(address creator, uint256 tokenId) external view returns (string memory);
}

// File: contracts/core/IERC721CreatorCore.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "./ICreatorCore.sol";

/**
 * @dev Core ERC721 creator interface
 */
interface IERC721CreatorCore is ICreatorCore {

    /**
     * @dev mint a token with no extension. Can only be called by an admin.
     * Returns tokenId minted
     */
    function mintBase(address to) external returns (uint256);

    /**
     * @dev mint a token with no extension. Can only be called by an admin.
     * Returns tokenId minted
     */
    function mintBase(address to, string calldata uri) external returns (uint256);

    /**
     * @dev batch mint a token with no extension. Can only be called by an admin.
     * Returns tokenId minted
     */
    function mintBaseBatch(address to, uint16 count) external returns (uint256[] memory);

    /**
     * @dev batch mint a token with no extension. Can only be called by an admin.
     * Returns tokenId minted
     */
    function mintBaseBatch(address to, string[] calldata uris) external returns (uint256[] memory);

    /**
     * @dev mint a token. Can only be called by a registered extension.
     * Returns tokenId minted
     */
    function mintExtension(address to) external returns (uint256);

    /**
     * @dev mint a token. Can only be called by a registered extension.
     * Returns tokenId minted
     */
    function mintExtension(address to, string calldata uri) external returns (uint256);

    /**
     * @dev batch mint a token. Can only be called by a registered extension.
     * Returns tokenIds minted
     */
    function mintExtensionBatch(address to, uint16 count) external returns (uint256[] memory);

    /**
     * @dev batch mint a token. Can only be called by a registered extension.
     * Returns tokenId minted
     */
    function mintExtensionBatch(address to, string[] calldata uris) external returns (uint256[] memory);

    /**
     * @dev burn a token. Can only be called by token owner or approved address.
     * On burn, calls back to the registered extension's onBurn method
     */
    function burn(uint256 tokenId) external;

}
// File: contracts/access/AdminControl.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./IAdminControl.sol";

abstract contract AdminControl is Ownable, IAdminControl, ERC165 {
    using EnumerableSet for EnumerableSet.AddressSet;

    // Track registered admins
    EnumerableSet.AddressSet private _admins;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return interfaceId == type(IAdminControl).interfaceId
            || super.supportsInterface(interfaceId);
    }

    /**
     * @dev Only allows approved admins to call the specified function
     */
    modifier adminRequired() {
        require(owner() == msg.sender || _admins.contains(msg.sender), "AdminControl: Must be owner or admin");
        _;
    }   

    /**
     * @dev See {IAdminControl-getAdmins}.
     */
    function getAdmins() external view override returns (address[] memory admins) {
        admins = new address[](_admins.length());
        for (uint i = 0; i < _admins.length(); i++) {
            admins[i] = _admins.at(i);
        }
        return admins;
    }

    /**
     * @dev See {IAdminControl-approveAdmin}.
     */
    function approveAdmin(address admin) external override onlyOwner {
        if (!_admins.contains(admin)) {
            emit AdminApproved(admin, msg.sender);
            _admins.add(admin);
        }
    }

    /**
     * @dev See {IAdminControl-revokeAdmin}.
     */
    function revokeAdmin(address admin) external override onlyOwner {
        if (_admins.contains(admin)) {
            emit AdminRevoked(admin, msg.sender);
            _admins.remove(admin);
        }
    }

    /**
     * @dev See {IAdminControl-isAdmin}.
     */
    function isAdmin(address admin) public override view returns (bool) {
        return (owner() == admin || _admins.contains(admin));
    }

}
// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

// File: contracts/core/ICreatorCore.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/utils/introspection/IERC165.sol";

/**
 * @dev Core creator interface
 */
interface ICreatorCore is IERC165 {

    event ExtensionRegistered(address indexed extension, address indexed sender);
    event ExtensionUnregistered(address indexed extension, address indexed sender);
    event ExtensionBlacklisted(address indexed extension, address indexed sender);
    event MintPermissionsUpdated(address indexed extension, address indexed permissions, address indexed sender);
    event RoyaltiesUpdated(uint256 indexed tokenId, address payable[] receivers, uint256[] basisPoints);
    event DefaultRoyaltiesUpdated(address payable[] receivers, uint256[] basisPoints);
    event ExtensionRoyaltiesUpdated(address indexed extension, address payable[] receivers, uint256[] basisPoints);
    event ExtensionApproveTransferUpdated(address indexed extension, bool enabled);

    /**
     * @dev gets address of all extensions
     */
    function getExtensions() external view returns (address[] memory);

    /**
     * @dev add an extension.  Can only be called by contract owner or admin.
     * extension address must point to a contract implementing ICreatorExtension.
     * Returns True if newly added, False if already added.
     */
    function registerExtension(address extension, string calldata baseURI) external;

    /**
     * @dev add an extension.  Can only be called by contract owner or admin.
     * extension address must point to a contract implementing ICreatorExtension.
     * Returns True if newly added, False if already added.
     */
    function registerExtension(address extension, string calldata baseURI, bool baseURIIdentical) external;

    /**
     * @dev add an extension.  Can only be called by contract owner or admin.
     * Returns True if removed, False if already removed.
     */
    function unregisterExtension(address extension) external;

    /**
     * @dev blacklist an extension.  Can only be called by contract owner or admin.
     * This function will destroy all ability to reference the metadata of any tokens created
     * by the specified extension. It will also unregister the extension if needed.
     * Returns True if removed, False if already removed.
     */
    function blacklistExtension(address extension) external;

    /**
     * @dev set the baseTokenURI of an extension.  Can only be called by extension.
     */
    function setBaseTokenURIExtension(string calldata uri) external;

    /**
     * @dev set the baseTokenURI of an extension.  Can only be called by extension.
     * For tokens with no uri configured, tokenURI will return "uri+tokenId"
     */
    function setBaseTokenURIExtension(string calldata uri, bool identical) external;

    /**
     * @dev set the common prefix of an extension.  Can only be called by extension.
     * If configured, and a token has a uri set, tokenURI will return "prefixURI+tokenURI"
     * Useful if you want to use ipfs/arweave
     */
    function setTokenURIPrefixExtension(string calldata prefix) external;

    /**
     * @dev set the tokenURI of a token extension.  Can only be called by extension that minted token.
     */
    function setTokenURIExtension(uint256 tokenId, string calldata uri) external;

    /**
     * @dev set the tokenURI of a token extension for multiple tokens.  Can only be called by extension that minted token.
     */
    function setTokenURIExtension(uint256[] memory tokenId, string[] calldata uri) external;

    /**
     * @dev set the baseTokenURI for tokens with no extension.  Can only be called by owner/admin.
     * For tokens with no uri configured, tokenURI will return "uri+tokenId"
     */
    function setBaseTokenURI(string calldata uri) external;

    /**
     * @dev set the common prefix for tokens with no extension.  Can only be called by owner/admin.
     * If configured, and a token has a uri set, tokenURI will return "prefixURI+tokenURI"
     * Useful if you want to use ipfs/arweave
     */
    function setTokenURIPrefix(string calldata prefix) external;

    /**
     * @dev set the tokenURI of a token with no extension.  Can only be called by owner/admin.
     */
    function setTokenURI(uint256 tokenId, string calldata uri) external;

    /**
     * @dev set the tokenURI of multiple tokens with no extension.  Can only be called by owner/admin.
     */
    function setTokenURI(uint256[] memory tokenIds, string[] calldata uris) external;

    /**
     * @dev set a permissions contract for an extension.  Used to control minting.
     */
    function setMintPermissions(address extension, address permissions) external;

    /**
     * @dev Configure so transfers of tokens created by the caller (must be extension) gets approval
     * from the extension before transferring
     */
    function setApproveTransferExtension(bool enabled) external;

    /**
     * @dev get the extension of a given token
     */
    function tokenExtension(uint256 tokenId) external view returns (address);

    /**
     * @dev Set default royalties
     */
    function setRoyalties(address payable[] calldata receivers, uint256[] calldata basisPoints) external;

    /**
     * @dev Set royalties of a token
     */
    function setRoyalties(uint256 tokenId, address payable[] calldata receivers, uint256[] calldata basisPoints) external;

    /**
     * @dev Set royalties of an extension
     */
    function setRoyaltiesExtension(address extension, address payable[] calldata receivers, uint256[] calldata basisPoints) external;

    /**
     * @dev Get royalites of a token.  Returns list of receivers and basisPoints
     */
    function getRoyalties(uint256 tokenId) external view returns (address payable[] memory, uint256[] memory);
    
    // Royalty support for various other standards
    function getFeeRecipients(uint256 tokenId) external view returns (address payable[] memory);
    function getFeeBps(uint256 tokenId) external view returns (uint[] memory);
    function getFees(uint256 tokenId) external view returns (address payable[] memory, uint256[] memory);
    function royaltyInfo(uint256 tokenId, uint256 value) external view returns (address, uint256);

}

// File: contracts/access/IAdminControl.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/utils/introspection/IERC165.sol";

/**
 * @dev Interface for admin control
 */
interface IAdminControl is IERC165 {

    event AdminApproved(address indexed account, address indexed sender);
    event AdminRevoked(address indexed account, address indexed sender);

    /**
     * @dev gets address of all admins
     */
    function getAdmins() external view returns (address[] memory);

    /**
     * @dev add an admin.  Can only be called by contract owner.
     */
    function approveAdmin(address admin) external;

    /**
     * @dev remove an admin.  Can only be called by contract owner.
     */
    function revokeAdmin(address admin) external;

    /**
     * @dev checks whether or not given address is an admin
     * Returns True if they are
     */
    function isAdmin(address admin) external view returns (bool);

}
// File: @openzeppelin/contracts/utils/structs/EnumerableSet.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            if (lastIndex != toDeleteIndex) {
                bytes32 lastvalue = set._values[lastIndex];

                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
            }

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        return _values(set._inner);
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;

        assembly {
            result := store
        }

        return result;
    }

    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;

        assembly {
            result := store
        }

        return result;
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// 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;
    }
}