// File: /contracts/eucliiid/xEUCLiD.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// Manifold Creator Extension
/// @author: eucliiid.xyz

////////////////////////////////////////////////////////////////////////////////////
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//                                                                                //
//                                                                                //
////////////////////////////////////////////////////////////////////////////////////                  
                    
import "../ERC721Creator.sol";

contract xEUCLiD is ERC721Creator("xEUCLiD","xE") {
}
// File: /contracts/permissions/ERC721/IERC721CreatorMintPermissions.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

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

/**
 * @dev Required interface of an ERC721Creator compliant extension contracts.
 */
interface IERC721CreatorMintPermissions is IERC165 {

    /**
     * @dev get approval to mint
     */
    function approveMint(address extension, address to, uint256 tokenId) 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/extensions/ERC721/IERC721CreatorExtensionBurnable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

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

/**
 * @dev Your extension is required to implement this interface if it wishes
 * to receive the onBurn callback whenever a token the extension created is
 * burned
 */
interface IERC721CreatorExtensionBurnable is IERC165 {
    /**
     * @dev callback handler for burn events
     */
    function onBurn(address owner, uint256 tokenId) external;
}
// File: /contracts/extensions/ERC721/IERC721CreatorExtensionApproveTransfer.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

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

/**
 * Implement this if you want your extension to approve a transfer
 */
interface IERC721CreatorExtensionApproveTransfer is IERC165 {

    /**
     * @dev Set whether or not the creator will check the extension for approval of token transfer
     */
    function setApproveTransfer(address creator, bool enabled) external;

    /**
     * @dev Called by creator contract to approve a transfer
     */
    function approveTransfer(address from, address to, uint256 tokenId) external returns (bool);
}

// 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/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/core/ERC721CreatorCore.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";

import "../extensions/ERC721/IERC721CreatorExtensionApproveTransfer.sol";
import "../extensions/ERC721/IERC721CreatorExtensionBurnable.sol";
import "../permissions/ERC721/IERC721CreatorMintPermissions.sol";
import "./IERC721CreatorCore.sol";
import "./CreatorCore.sol";

/**
 * @dev Core ERC721 creator implementation
 */
abstract contract ERC721CreatorCore is CreatorCore, IERC721CreatorCore {

    using EnumerableSet for EnumerableSet.AddressSet;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(CreatorCore, IERC165) returns (bool) {
        return interfaceId == type(IERC721CreatorCore).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {ICreatorCore-setApproveTransferExtension}.
     */
    function setApproveTransferExtension(bool enabled) external override extensionRequired {
        require(!enabled || ERC165Checker.supportsInterface(msg.sender, type(IERC721CreatorExtensionApproveTransfer).interfaceId), "Extension must implement IERC721CreatorExtensionApproveTransfer");
        if (_extensionApproveTransfers[msg.sender] != enabled) {
            _extensionApproveTransfers[msg.sender] = enabled;
            emit ExtensionApproveTransferUpdated(msg.sender, enabled);
        }
    }

    /**
     * @dev Set mint permissions for an extension
     */
    function _setMintPermissions(address extension, address permissions) internal {
        require(_extensions.contains(extension), "CreatorCore: Invalid extension");
        require(permissions == address(0x0) || ERC165Checker.supportsInterface(permissions, type(IERC721CreatorMintPermissions).interfaceId), "Invalid address");
        if (_extensionPermissions[extension] != permissions) {
            _extensionPermissions[extension] = permissions;
            emit MintPermissionsUpdated(extension, permissions, msg.sender);
        }
    }

    /**
     * Check if an extension can mint
     */
    function _checkMintPermissions(address to, uint256 tokenId) internal {
        if (_extensionPermissions[msg.sender] != address(0x0)) {
            IERC721CreatorMintPermissions(_extensionPermissions[msg.sender]).approveMint(msg.sender, to, tokenId);
        }
    }

    /**
     * Override for post mint actions
     */
    function _postMintBase(address, uint256) internal virtual {}

    
    /**
     * Override for post mint actions
     */
    function _postMintExtension(address, uint256) internal virtual {}

    /**
     * Post-burning callback and metadata cleanup
     */
    function _postBurn(address owner, uint256 tokenId) internal virtual {
        // Callback to originating extension if needed
        if (_tokensExtension[tokenId] != address(this)) {
           if (ERC165Checker.supportsInterface(_tokensExtension[tokenId], type(IERC721CreatorExtensionBurnable).interfaceId)) {
               IERC721CreatorExtensionBurnable(_tokensExtension[tokenId]).onBurn(owner, tokenId);
           }
        }
        // Clear metadata (if any)
        if (bytes(_tokenURIs[tokenId]).length != 0) {
            delete _tokenURIs[tokenId];
        }    
        // Delete token origin extension tracking
        delete _tokensExtension[tokenId];    
    }

    /**
     * Approve a transfer
     */
    function _approveTransfer(address from, address to, uint256 tokenId) internal {
       if (_extensionApproveTransfers[_tokensExtension[tokenId]]) {
           require(IERC721CreatorExtensionApproveTransfer(_tokensExtension[tokenId]).approveTransfer(from, to, tokenId), "ERC721Creator: Extension approval failure");
       }
    }

}
// File: /contracts/core/CreatorCore.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165Checker.sol";
import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";

import "../extensions/ICreatorExtensionTokenURI.sol";

import "./ICreatorCore.sol";

/**
 * @dev Core creator implementation
 */
abstract contract CreatorCore is ReentrancyGuardUpgradeable, ICreatorCore, ERC165 {
    using Strings for uint256;
    using EnumerableSet for EnumerableSet.AddressSet;
    using AddressUpgradeable for address;

    uint256 _tokenCount;

    // Track registered extensions data
    EnumerableSet.AddressSet internal _extensions;
    EnumerableSet.AddressSet internal _blacklistedExtensions;
    mapping (address => address) internal _extensionPermissions;
    mapping (address => bool) internal _extensionApproveTransfers;
    
    // For tracking which extension a token was minted by
    mapping (uint256 => address) internal _tokensExtension;

    // The baseURI for a given extension
    mapping (address => string) private _extensionBaseURI;
    mapping (address => bool) private _extensionBaseURIIdentical;

    // The prefix for any tokens with a uri configured
    mapping (address => string) private _extensionURIPrefix;

    // Mapping for individual token URIs
    mapping (uint256 => string) internal _tokenURIs;

    
    // Royalty configurations
    mapping (address => address payable[]) internal _extensionRoyaltyReceivers;
    mapping (address => uint256[]) internal _extensionRoyaltyBPS;
    mapping (uint256 => address payable[]) internal _tokenRoyaltyReceivers;
    mapping (uint256 => uint256[]) internal _tokenRoyaltyBPS;

    /**
     * External interface identifiers for royalties
     */

    /**
     *  @dev CreatorCore
     *
     *  bytes4(keccak256('getRoyalties(uint256)')) == 0xbb3bafd6
     *
     *  => 0xbb3bafd6 = 0xbb3bafd6
     */
    bytes4 private constant _INTERFACE_ID_ROYALTIES_CREATORCORE = 0xbb3bafd6;

    /**
     *  @dev Rarible: RoyaltiesV1
     *
     *  bytes4(keccak256('getFeeRecipients(uint256)')) == 0xb9c4d9fb
     *  bytes4(keccak256('getFeeBps(uint256)')) == 0x0ebd4c7f
     *
     *  => 0xb9c4d9fb ^ 0x0ebd4c7f = 0xb7799584
     */
    bytes4 private constant _INTERFACE_ID_ROYALTIES_RARIBLE = 0xb7799584;

    /**
     *  @dev Foundation
     *
     *  bytes4(keccak256('getFees(uint256)')) == 0xd5a06d4c
     *
     *  => 0xd5a06d4c = 0xd5a06d4c
     */
    bytes4 private constant _INTERFACE_ID_ROYALTIES_FOUNDATION = 0xd5a06d4c;

    /**
     *  @dev EIP-2981
     *
     * bytes4(keccak256("royaltyInfo(uint256,uint256)")) == 0x2a55205a
     *
     * => 0x2a55205a = 0x2a55205a
     */
    bytes4 private constant _INTERFACE_ID_ROYALTIES_EIP2981 = 0x2a55205a;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return interfaceId == type(ICreatorCore).interfaceId || super.supportsInterface(interfaceId)
            || interfaceId == _INTERFACE_ID_ROYALTIES_CREATORCORE || interfaceId == _INTERFACE_ID_ROYALTIES_RARIBLE
            || interfaceId == _INTERFACE_ID_ROYALTIES_FOUNDATION || interfaceId == _INTERFACE_ID_ROYALTIES_EIP2981;
    }

    /**
     * @dev Only allows registered extensions to call the specified function
     */
    modifier extensionRequired() {
        require(_extensions.contains(msg.sender), "Must be registered extension");
        _;
    }

    /**
     * @dev Only allows non-blacklisted extensions
     */
    modifier nonBlacklistRequired(address extension) {
        require(!_blacklistedExtensions.contains(extension), "Extension blacklisted");
        _;
    }   

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

    /**
     * @dev Register an extension
     */
    function _registerExtension(address extension, string calldata baseURI, bool baseURIIdentical) internal {
        require(extension != address(this), "Creator: Invalid");
        require(extension.isContract(), "Creator: Extension must be a contract");
        if (!_extensions.contains(extension)) {
            _extensionBaseURI[extension] = baseURI;
            _extensionBaseURIIdentical[extension] = baseURIIdentical;
            emit ExtensionRegistered(extension, msg.sender);
            _extensions.add(extension);
        }
    }

    /**
     * @dev Unregister an extension
     */
    function _unregisterExtension(address extension) internal {
       if (_extensions.contains(extension)) {
           emit ExtensionUnregistered(extension, msg.sender);
           _extensions.remove(extension);
       }
    }

    /**
     * @dev Blacklist an extension
     */
    function _blacklistExtension(address extension) internal {
       require(extension != address(this), "Cannot blacklist yourself");
       if (_extensions.contains(extension)) {
           emit ExtensionUnregistered(extension, msg.sender);
           _extensions.remove(extension);
       }
       if (!_blacklistedExtensions.contains(extension)) {
           emit ExtensionBlacklisted(extension, msg.sender);
           _blacklistedExtensions.add(extension);
       }
    }

    /**
     * @dev Set base token uri for an extension
     */
    function _setBaseTokenURIExtension(string calldata uri, bool identical) internal {
        _extensionBaseURI[msg.sender] = uri;
        _extensionBaseURIIdentical[msg.sender] = identical;
    }

    /**
     * @dev Set token uri prefix for an extension
     */
    function _setTokenURIPrefixExtension(string calldata prefix) internal {
        _extensionURIPrefix[msg.sender] = prefix;
    }

    /**
     * @dev Set token uri for a token of an extension
     */
    function _setTokenURIExtension(uint256 tokenId, string calldata uri) internal {
        require(_tokensExtension[tokenId] == msg.sender, "Invalid token");
        _tokenURIs[tokenId] = uri;
    }

    /**
     * @dev Set base token uri for tokens with no extension
     */
    function _setBaseTokenURI(string memory uri) internal {
        _extensionBaseURI[address(this)] = uri;
    }

    /**
     * @dev Set token uri prefix for tokens with no extension
     */
    function _setTokenURIPrefix(string calldata prefix) internal {
        _extensionURIPrefix[address(this)] = prefix;
    }


    /**
     * @dev Set token uri for a token with no extension
     */
    function _setTokenURI(uint256 tokenId, string calldata uri) internal {
        require(_tokensExtension[tokenId] == address(this), "Invalid token");
        _tokenURIs[tokenId] = uri;
    }

    /**
     * @dev Retrieve a token's URI
     */
    function _tokenURI(uint256 tokenId) internal view returns (string memory) {
        address extension = _tokensExtension[tokenId];
        require(!_blacklistedExtensions.contains(extension), "Extension blacklisted");

        if (bytes(_tokenURIs[tokenId]).length != 0) {
            if (bytes(_extensionURIPrefix[extension]).length != 0) {
                return string(abi.encodePacked(_extensionURIPrefix[extension],_tokenURIs[tokenId]));
            }
            return _tokenURIs[tokenId];
        }

        if (ERC165Checker.supportsInterface(extension, type(ICreatorExtensionTokenURI).interfaceId)) {
            return ICreatorExtensionTokenURI(extension).tokenURI(address(this), tokenId);
        }

        if (!_extensionBaseURIIdentical[extension]) {
            return string(abi.encodePacked(_extensionBaseURI[extension], tokenId.toString()));
        } else {
            return _extensionBaseURI[extension];
        }
    }

    /**
     * Get token extension
     */
    function _tokenExtension(uint256 tokenId) internal view returns (address extension) {
        extension = _tokensExtension[tokenId];

        require(extension != address(this), "No extension for token");
        require(!_blacklistedExtensions.contains(extension), "Extension blacklisted");

        return extension;
    }

    /**
     * Helper to get royalties for a token
     */
    function _getRoyalties(uint256 tokenId) view internal returns (address payable[] storage, uint256[] storage) {
        return (_getRoyaltyReceivers(tokenId), _getRoyaltyBPS(tokenId));
    }

    /**
     * Helper to get royalty receivers for a token
     */
    function _getRoyaltyReceivers(uint256 tokenId) view internal returns (address payable[] storage) {
        if (_tokenRoyaltyReceivers[tokenId].length > 0) {
            return _tokenRoyaltyReceivers[tokenId];
        } else if (_extensionRoyaltyReceivers[_tokensExtension[tokenId]].length > 0) {
            return _extensionRoyaltyReceivers[_tokensExtension[tokenId]];
        }
        return _extensionRoyaltyReceivers[address(this)];        
    }

    /**
     * Helper to get royalty basis points for a token
     */
    function _getRoyaltyBPS(uint256 tokenId) view internal returns (uint256[] storage) {
        if (_tokenRoyaltyBPS[tokenId].length > 0) {
            return _tokenRoyaltyBPS[tokenId];
        } else if (_extensionRoyaltyBPS[_tokensExtension[tokenId]].length > 0) {
            return _extensionRoyaltyBPS[_tokensExtension[tokenId]];
        }
        return _extensionRoyaltyBPS[address(this)];        
    }

    function _getRoyaltyInfo(uint256 tokenId, uint256 value) view internal returns (address receiver, uint256 amount){
        address payable[] storage receivers = _getRoyaltyReceivers(tokenId);
        require(receivers.length <= 1, "More than 1 royalty receiver");
        
        if (receivers.length == 0) {
            return (address(this), 0);
        }
        return (receivers[0], _getRoyaltyBPS(tokenId)[0]*value/10000);
    }

    /**
     * Set royalties for a token
     */
    function _setRoyalties(uint256 tokenId, address payable[] calldata receivers, uint256[] calldata basisPoints) internal {
        require(receivers.length == basisPoints.length, "Invalid input");
        uint256 totalBasisPoints;
        for (uint i = 0; i < basisPoints.length; i++) {
            totalBasisPoints += basisPoints[i];
        }
        require(totalBasisPoints < 10000, "Invalid total royalties");
        _tokenRoyaltyReceivers[tokenId] = receivers;
        _tokenRoyaltyBPS[tokenId] = basisPoints;
        emit RoyaltiesUpdated(tokenId, receivers, basisPoints);
    }

    /**
     * Set royalties for all tokens of an extension
     */
    function _setRoyaltiesExtension(address extension, address payable[] calldata receivers, uint256[] calldata basisPoints) internal {
        require(receivers.length == basisPoints.length, "Invalid input");
        uint256 totalBasisPoints;
        for (uint i = 0; i < basisPoints.length; i++) {
            totalBasisPoints += basisPoints[i];
        }
        require(totalBasisPoints < 10000, "Invalid total royalties");
        _extensionRoyaltyReceivers[extension] = receivers;
        _extensionRoyaltyBPS[extension] = basisPoints;
        if (extension == address(this)) {
            emit DefaultRoyaltiesUpdated(receivers, basisPoints);
        } else {
            emit ExtensionRoyaltiesUpdated(extension, receivers, basisPoints);
        }
    }


}

// File: /contracts/ERC721Creator.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";

import "@manifoldxyz/libraries-solidity/contracts/access/AdminControl.sol";
import "./core/ERC721CreatorCore.sol";

/**
 * @dev ERC721Creator implementation
 */
contract ERC721Creator is AdminControl, ERC721, ERC721CreatorCore {

    constructor (string memory _name, string memory _symbol) ERC721(_name, _symbol) {
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721, ERC721CreatorCore, AdminControl) returns (bool) {
        return ERC721CreatorCore.supportsInterface(interfaceId) || ERC721.supportsInterface(interfaceId) || AdminControl.supportsInterface(interfaceId);
    }

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

    /**
     * @dev See {ICreatorCore-registerExtension}.
     */
    function registerExtension(address extension, string calldata baseURI) external override adminRequired nonBlacklistRequired(extension) {
        _registerExtension(extension, baseURI, false);
    }

    /**
     * @dev See {ICreatorCore-registerExtension}.
     */
    function registerExtension(address extension, string calldata baseURI, bool baseURIIdentical) external override adminRequired nonBlacklistRequired(extension) {
        _registerExtension(extension, baseURI, baseURIIdentical);
    }


    /**
     * @dev See {ICreatorCore-unregisterExtension}.
     */
    function unregisterExtension(address extension) external override adminRequired {
        _unregisterExtension(extension);
    }

    /**
     * @dev See {ICreatorCore-blacklistExtension}.
     */
    function blacklistExtension(address extension) external override adminRequired {
        _blacklistExtension(extension);
    }

    /**
     * @dev See {ICreatorCore-setBaseTokenURIExtension}.
     */
    function setBaseTokenURIExtension(string calldata uri) external override extensionRequired {
        _setBaseTokenURIExtension(uri, false);
    }

    /**
     * @dev See {ICreatorCore-setBaseTokenURIExtension}.
     */
    function setBaseTokenURIExtension(string calldata uri, bool identical) external override extensionRequired {
        _setBaseTokenURIExtension(uri, identical);
    }

    /**
     * @dev See {ICreatorCore-setTokenURIPrefixExtension}.
     */
    function setTokenURIPrefixExtension(string calldata prefix) external override extensionRequired {
        _setTokenURIPrefixExtension(prefix);
    }

    /**
     * @dev See {ICreatorCore-setTokenURIExtension}.
     */
    function setTokenURIExtension(uint256 tokenId, string calldata uri) external override extensionRequired {
        _setTokenURIExtension(tokenId, uri);
    }

    /**
     * @dev See {ICreatorCore-setTokenURIExtension}.
     */
    function setTokenURIExtension(uint256[] memory tokenIds, string[] calldata uris) external override extensionRequired {
        require(tokenIds.length == uris.length, "Invalid input");
        for (uint i = 0; i < tokenIds.length; i++) {
            _setTokenURIExtension(tokenIds[i], uris[i]);            
        }
    }

    /**
     * @dev See {ICreatorCore-setBaseTokenURI}.
     */
    function setBaseTokenURI(string calldata uri) external override adminRequired {
        _setBaseTokenURI(uri);
    }

    /**
     * @dev See {ICreatorCore-setTokenURIPrefix}.
     */
    function setTokenURIPrefix(string calldata prefix) external override adminRequired {
        _setTokenURIPrefix(prefix);
    }

    /**
     * @dev See {ICreatorCore-setTokenURI}.
     */
    function setTokenURI(uint256 tokenId, string calldata uri) external override adminRequired {
        _setTokenURI(tokenId, uri);
    }

    /**
     * @dev See {ICreatorCore-setTokenURI}.
     */
    function setTokenURI(uint256[] memory tokenIds, string[] calldata uris) external override adminRequired {
        require(tokenIds.length == uris.length, "Invalid input");
        for (uint i = 0; i < tokenIds.length; i++) {
            _setTokenURI(tokenIds[i], uris[i]);            
        }
    }

    /**
     * @dev See {ICreatorCore-setMintPermissions}.
     */
    function setMintPermissions(address extension, address permissions) external override adminRequired {
        _setMintPermissions(extension, permissions);
    }

    /**
     * @dev See {IERC721CreatorCore-mintBase}.
     */
    function mintBase(address to) public virtual override nonReentrant adminRequired returns(uint256) {
        return _mintBase(to, "");
    }

    /**
     * @dev See {IERC721CreatorCore-mintBase}.
     */
    function mintBase(address to, string calldata uri) public virtual override nonReentrant adminRequired returns(uint256) {
        return _mintBase(to, uri);
    }

    /**
     * @dev See {IERC721CreatorCore-mintBaseBatch}.
     */
    function mintBaseBatch(address to, uint16 count) public virtual override nonReentrant adminRequired returns(uint256[] memory tokenIds) {
        tokenIds = new uint256[](count);
        for (uint16 i = 0; i < count; i++) {
            tokenIds[i] = _mintBase(to, "");
        }
        return tokenIds;
    }

    /**
     * @dev See {IERC721CreatorCore-mintBaseBatch}.
     */
    function mintBaseBatch(address to, string[] calldata uris) public virtual override nonReentrant adminRequired returns(uint256[] memory tokenIds) {
        tokenIds = new uint256[](uris.length);
        for (uint i = 0; i < uris.length; i++) {
            tokenIds[i] = _mintBase(to, uris[i]);
        }
        return tokenIds;
    }

    /**
     * @dev Mint token with no extension
     */
    function _mintBase(address to, string memory uri) internal virtual returns(uint256 tokenId) {
        _tokenCount++;
        tokenId = _tokenCount;

        // Track the extension that minted the token
        _tokensExtension[tokenId] = address(this);

        _safeMint(to, tokenId);

        if (bytes(uri).length > 0) {
            _tokenURIs[tokenId] = uri;
        }

        // Call post mint
        _postMintBase(to, tokenId);
        return tokenId;
    }


    /**
     * @dev See {IERC721CreatorCore-mintExtension}.
     */
    function mintExtension(address to) public virtual override nonReentrant extensionRequired returns(uint256) {
        return _mintExtension(to, "");
    }

    /**
     * @dev See {IERC721CreatorCore-mintExtension}.
     */
    function mintExtension(address to, string calldata uri) public virtual override nonReentrant extensionRequired returns(uint256) {
        return _mintExtension(to, uri);
    }

    /**
     * @dev See {IERC721CreatorCore-mintExtensionBatch}.
     */
    function mintExtensionBatch(address to, uint16 count) public virtual override nonReentrant extensionRequired returns(uint256[] memory tokenIds) {
        tokenIds = new uint256[](count);
        for (uint16 i = 0; i < count; i++) {
            tokenIds[i] = _mintExtension(to, "");
        }
        return tokenIds;
    }

    /**
     * @dev See {IERC721CreatorCore-mintExtensionBatch}.
     */
    function mintExtensionBatch(address to, string[] calldata uris) public virtual override nonReentrant extensionRequired returns(uint256[] memory tokenIds) {
        tokenIds = new uint256[](uris.length);
        for (uint i = 0; i < uris.length; i++) {
            tokenIds[i] = _mintExtension(to, uris[i]);
        }
    }
    
    /**
     * @dev Mint token via extension
     */
    function _mintExtension(address to, string memory uri) internal virtual returns(uint256 tokenId) {
        _tokenCount++;
        tokenId = _tokenCount;

        _checkMintPermissions(to, tokenId);

        // Track the extension that minted the token
        _tokensExtension[tokenId] = msg.sender;

        _safeMint(to, tokenId);

        if (bytes(uri).length > 0) {
            _tokenURIs[tokenId] = uri;
        }
        
        // Call post mint
        _postMintExtension(to, tokenId);
        return tokenId;
    }

    /**
     * @dev See {IERC721CreatorCore-tokenExtension}.
     */
    function tokenExtension(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "Nonexistent token");
        return _tokenExtension(tokenId);
    }

    /**
     * @dev See {IERC721CreatorCore-burn}.
     */
    function burn(uint256 tokenId) public virtual override nonReentrant {
        require(_isApprovedOrOwner(msg.sender, tokenId), "Caller is not owner nor approved");
        address owner = ownerOf(tokenId);
        _burn(tokenId);
        _postBurn(owner, tokenId);
    }

    /**
     * @dev See {ICreatorCore-setRoyalties}.
     */
    function setRoyalties(address payable[] calldata receivers, uint256[] calldata basisPoints) external override adminRequired {
        _setRoyaltiesExtension(address(this), receivers, basisPoints);
    }

    /**
     * @dev See {ICreatorCore-setRoyalties}.
     */
    function setRoyalties(uint256 tokenId, address payable[] calldata receivers, uint256[] calldata basisPoints) external override adminRequired {
        require(_exists(tokenId), "Nonexistent token");
        _setRoyalties(tokenId, receivers, basisPoints);
    }

    /**
     * @dev See {ICreatorCore-setRoyaltiesExtension}.
     */
    function setRoyaltiesExtension(address extension, address payable[] calldata receivers, uint256[] calldata basisPoints) external override adminRequired {
        _setRoyaltiesExtension(extension, receivers, basisPoints);
    }

    /**
     * @dev {See ICreatorCore-getRoyalties}.
     */
    function getRoyalties(uint256 tokenId) external view virtual override returns (address payable[] memory, uint256[] memory) {
        require(_exists(tokenId), "Nonexistent token");
        return _getRoyalties(tokenId);
    }

    /**
     * @dev {See ICreatorCore-getFees}.
     */
    function getFees(uint256 tokenId) external view virtual override returns (address payable[] memory, uint256[] memory) {
        require(_exists(tokenId), "Nonexistent token");
        return _getRoyalties(tokenId);
    }

    /**
     * @dev {See ICreatorCore-getFeeRecipients}.
     */
    function getFeeRecipients(uint256 tokenId) external view virtual override returns (address payable[] memory) {
        require(_exists(tokenId), "Nonexistent token");
        return _getRoyaltyReceivers(tokenId);
    }

    /**
     * @dev {See ICreatorCore-getFeeBps}.
     */
    function getFeeBps(uint256 tokenId) external view virtual override returns (uint[] memory) {
        require(_exists(tokenId), "Nonexistent token");
        return _getRoyaltyBPS(tokenId);
    }
    
    /**
     * @dev {See ICreatorCore-royaltyInfo}.
     */
    function royaltyInfo(uint256 tokenId, uint256 value) external view virtual override returns (address, uint256) {
        require(_exists(tokenId), "Nonexistent token");
        return _getRoyaltyInfo(tokenId, value);
    } 

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "Nonexistent token");
        return _tokenURI(tokenId);
    }
    
}
// File: @openzeppelin/contracts/utils/structs/EnumerableSet.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/structs/EnumerableSet.sol)

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/introspection/IERC165.sol



// SPDX-License-Identifier: MIT
// 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);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165Checker.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165Checker.sol)

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Library used to query support of an interface declared via {IERC165}.
 *
 * Note that these functions return the actual result of the query: they do not
 * `revert` if an interface is not supported. It is up to the caller to decide
 * what to do in these cases.
 */
library ERC165Checker {
    // As per the EIP-165 spec, no interface should ever match 0xffffffff
    bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;

    /**
     * @dev Returns true if `account` supports the {IERC165} interface,
     */
    function supportsERC165(address account) internal view returns (bool) {
        // Any contract that implements ERC165 must explicitly indicate support of
        // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
        return
            _supportsERC165Interface(account, type(IERC165).interfaceId) &&
            !_supportsERC165Interface(account, _INTERFACE_ID_INVALID);
    }

    /**
     * @dev Returns true if `account` supports the interface defined by
     * `interfaceId`. Support for {IERC165} itself is queried automatically.
     *
     * See {IERC165-supportsInterface}.
     */
    function supportsInterface(address account, bytes4 interfaceId) internal view returns (bool) {
        // query support of both ERC165 as per the spec and support of _interfaceId
        return supportsERC165(account) && _supportsERC165Interface(account, interfaceId);
    }

    /**
     * @dev Returns a boolean array where each value corresponds to the
     * interfaces passed in and whether they're supported or not. This allows
     * you to batch check interfaces for a contract where your expectation
     * is that some interfaces may not be supported.
     *
     * See {IERC165-supportsInterface}.
     *
     * _Available since v3.4._
     */
    function getSupportedInterfaces(address account, bytes4[] memory interfaceIds)
        internal
        view
        returns (bool[] memory)
    {
        // an array of booleans corresponding to interfaceIds and whether they're supported or not
        bool[] memory interfaceIdsSupported = new bool[](interfaceIds.length);

        // query support of ERC165 itself
        if (supportsERC165(account)) {
            // query support of each interface in interfaceIds
            for (uint256 i = 0; i < interfaceIds.length; i++) {
                interfaceIdsSupported[i] = _supportsERC165Interface(account, interfaceIds[i]);
            }
        }

        return interfaceIdsSupported;
    }

    /**
     * @dev Returns true if `account` supports all the interfaces defined in
     * `interfaceIds`. Support for {IERC165} itself is queried automatically.
     *
     * Batch-querying can lead to gas savings by skipping repeated checks for
     * {IERC165} support.
     *
     * See {IERC165-supportsInterface}.
     */
    function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) internal view returns (bool) {
        // query support of ERC165 itself
        if (!supportsERC165(account)) {
            return false;
        }

        // query support of each interface in _interfaceIds
        for (uint256 i = 0; i < interfaceIds.length; i++) {
            if (!_supportsERC165Interface(account, interfaceIds[i])) {
                return false;
            }
        }

        // all interfaces supported
        return true;
    }

    /**
     * @notice Query if a contract implements an interface, does not check ERC165 support
     * @param account The address of the contract to query for support of an interface
     * @param interfaceId The interface identifier, as specified in ERC-165
     * @return true if the contract at account indicates support of the interface with
     * identifier interfaceId, false otherwise
     * @dev Assumes that account contains a contract that supports ERC165, otherwise
     * the behavior of this method is undefined. This precondition can be checked
     * with {supportsERC165}.
     * Interface identification is specified in ERC-165.
     */
    function _supportsERC165Interface(address account, bytes4 interfaceId) private view returns (bool) {
        bytes memory encodedParams = abi.encodeWithSelector(IERC165.supportsInterface.selector, interfaceId);
        (bool success, bytes memory result) = account.staticcall{gas: 30000}(encodedParams);
        if (result.length < 32) return false;
        return success && abi.decode(result, (bool));
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

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
// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)

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/utils/Context.sol



// 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;
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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 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);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)

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);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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: @openzeppelin/contracts/token/ERC721/ERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol)

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 {
        _setApprovalForAll(_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);

        _afterTokenTransfer(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);

        _afterTokenTransfer(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 from incorrect owner");
        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);

        _afterTokenTransfer(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 Approve `operator` to operate on all of `owner` tokens
     *
     * Emits a {ApprovalForAll} event.
     */
    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);
    }

    /**
     * @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.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 {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)

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() {
        _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(), "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 {
        _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);
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @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 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 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);
            }
        }
    }
}

// File: @openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";

/**
 * @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 ReentrancyGuardUpgradeable is Initializable {
    // 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;

    function __ReentrancyGuard_init() internal onlyInitializing {
        __ReentrancyGuard_init_unchained();
    }

    function __ReentrancyGuard_init_unchained() internal onlyInitializing {
        _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 making 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;
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[49] private __gap;
}

// File: @openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (proxy/utils/Initializable.sol)

pragma solidity ^0.8.0;

import "../../utils/AddressUpgradeable.sol";

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
 * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() initializer {}
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        // If the contract is initializing we ignore whether _initialized is set in order to support multiple
        // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
        // contract may have been reentered.
        require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} modifier, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }

    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

// File: @manifoldxyz/libraries-solidity/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: @manifoldxyz/libraries-solidity/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));
    }

}