// SPDX-License-Identifier: GPL-3.0-or-later pragma solidity ^0.8.17; import {IERC721Receiver} from '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol'; import {IERC1155Receiver} from '@openzeppelin/contracts/token/ERC1155/IERC1155Receiver.sol'; import {IERC165} from '@openzeppelin/contracts/utils/introspection/IERC165.sol'; /// @title ERC Callback Support /// @notice Implements various functions introduced by a variety of ERCs for security reasons. /// All are called by external contracts to ensure that this contract safely supports the ERC in question. contract Callbacks is IERC721Receiver, IERC1155Receiver { function onERC721Received(address, address, uint256, bytes calldata) external pure returns (bytes4) { return this.onERC721Received.selector; } function onERC1155Received(address, address, uint256, uint256, bytes calldata) external pure returns (bytes4) { return this.onERC1155Received.selector; } function onERC1155BatchReceived(address, address, uint256[] calldata, uint256[] calldata, bytes calldata) external pure returns (bytes4) { return this.onERC1155BatchReceived.selector; } function supportsInterface(bytes4 interfaceId) external pure returns (bool) { return interfaceId == type(IERC1155Receiver).interfaceId || interfaceId == type(IERC721Receiver).interfaceId || interfaceId == type(IERC165).interfaceId; } }