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Contract Library for the Ethereum and Fantom blockchains by Dedaub

OPERATOR_FILTER_REGISTRY

SUBSCRIPTION

operator

from

approveTransfer

interfaceId

supportsInterface

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.2) (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) {
        // prepare call
        bytes memory encodedParams = abi.encodeWithSelector(IERC165.supportsInterface.selector, interfaceId);

        // perform static call
        bool success;
        uint256 returnSize;
        uint256 returnValue;
        assembly {
            success := staticcall(30000, account, add(encodedParams, 0x20), mload(encodedParams), 0x00, 0x20)
            returnSize := returndatasize()
            returnValue := mload(0x00)
        }

        return success && returnSize >= 0x20 && returnValue > 0;
    }
}

ERC165Checker.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "IERC165.sol";

/**
 * Implement this if you want your extension to approve a transfer
 */
interface IERC1155CreatorExtensionApproveTransfer is IERC165 {

    /**
     * @dev Set whether or not the creator contract 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 operator, address from, address to, uint256[] calldata tokenIds, uint256[] calldata amounts) external returns (bool);
}

IERC1155CreatorExtensionApproveTransfer.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);
}

IERC165.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "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 operator, address from, address to, uint256 tokenId) external returns (bool);
}

IERC721CreatorExtensionApproveTransfer.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

interface IOperatorFilterRegistry {
    function isOperatorAllowed(address registrant, address operator) external view returns (bool);
    function register(address registrant) external;
    function registerAndSubscribe(address registrant, address subscription) external;
    function registerAndCopyEntries(address registrant, address registrantToCopy) external;
    function unregister(address addr) external;
    function updateOperator(address registrant, address operator, bool filtered) external;
    function updateOperators(address registrant, address[] calldata operators, bool filtered) external;
    function updateCodeHash(address registrant, bytes32 codehash, bool filtered) external;
    function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered) external;
    function subscribe(address registrant, address registrantToSubscribe) external;
    function unsubscribe(address registrant, bool copyExistingEntries) external;
    function subscriptionOf(address addr) external returns (address registrant);
    function subscribers(address registrant) external returns (address[] memory);
    function subscriberAt(address registrant, uint256 index) external returns (address);
    function copyEntriesOf(address registrant, address registrantToCopy) external;
    function isOperatorFiltered(address registrant, address operator) external returns (bool);
    function isCodeHashOfFiltered(address registrant, address operatorWithCode) external returns (bool);
    function isCodeHashFiltered(address registrant, bytes32 codeHash) external returns (bool);
    function filteredOperators(address addr) external returns (address[] memory);
    function filteredCodeHashes(address addr) external returns (bytes32[] memory);
    function filteredOperatorAt(address registrant, uint256 index) external returns (address);
    function filteredCodeHashAt(address registrant, uint256 index) external returns (bytes32);
    function isRegistered(address addr) external returns (bool);
    function codeHashOf(address addr) external returns (bytes32);
}

IOperatorFilterRegistry.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

import "IERC721CreatorExtensionApproveTransfer.sol";
import "IERC1155CreatorExtensionApproveTransfer.sol";
import {IOperatorFilterRegistry} from "IOperatorFilterRegistry.sol";
import "ERC165Checker.sol";

contract OperatorFilterer is IERC165 {
    error OperatorNotAllowed(address operator);

    address public immutable OPERATOR_FILTER_REGISTRY;
    address public immutable SUBSCRIPTION;

    constructor(address operatorFilterRegistry, address subscription) {
        OPERATOR_FILTER_REGISTRY = operatorFilterRegistry;
        SUBSCRIPTION = subscription;

        IOperatorFilterRegistry(OPERATOR_FILTER_REGISTRY).registerAndSubscribe(address(this), SUBSCRIPTION);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override (IERC165) returns (bool) {
        return interfaceId == type(IERC721CreatorExtensionApproveTransfer).interfaceId
            || interfaceId == type(IERC1155CreatorExtensionApproveTransfer).interfaceId
            || interfaceId == type(IERC165).interfaceId;
    }

    /**
     * @dev ERC1155: Called by creator contract to approve a transfer
     */
    function approveTransfer(address operator, address from, address, uint256[] calldata, uint256[] calldata)
        external
        view
        returns (bool)
    {
        return isOperatorAllowed(operator, from);
    }

    /**
     * @dev ERC721: Called by creator contract to approve a transfer
     */
    function approveTransfer(address operator, address from, address, uint256) external view returns (bool) {
        return isOperatorAllowed(operator, from);
    }

    /**
     * @dev Check OperatorFiltererRegistry to see if operator is approved
     */
    function isOperatorAllowed(address operator, address from) internal view returns (bool) {
        if (from != operator) {
            if (!IOperatorFilterRegistry(OPERATOR_FILTER_REGISTRY).isOperatorAllowed(address(this), operator)) {
                revert OperatorNotAllowed(operator);
            }
        }

        return true;
    }
}