| |
| pragma solidity ^0.8.20; |
|
|
| import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol"; |
| import {EIP712} from "@openzeppelin/contracts/utils/cryptography/EIP712.sol"; |
| import {ECDSA} from "@openzeppelin/contracts/utils/cryptography/ECDSA.sol"; |
|
|
| contract PermitCollection is ERC721, EIP712 { |
| address public immutable issuer; |
| bytes32 public constant PERMIT_TYPEHASH = |
| keccak256("Permit(address spender,uint256 tokenId,uint256 nonce,uint256 deadline)"); |
|
|
| mapping(uint256 => uint256) private _nonces; |
|
|
| constructor() ERC721("Collection", "NFT") EIP712("Collection", "1") { |
| issuer = msg.sender; |
| } |
|
|
| function mint(address to, uint256 tokenId) external { |
| require(msg.sender == issuer, "only issuer"); |
| _mint(to, tokenId); |
| } |
|
|
| function nonces(uint256 tokenId) external view returns (uint256) { |
| _requireOwned(tokenId); |
| return _nonces[tokenId]; |
| } |
|
|
| function DOMAIN_SEPARATOR() external view returns (bytes32) { |
| return _domainSeparatorV4(); |
| } |
|
|
| function bumpNonce(uint256 tokenId) external { |
| address owner = _requireOwned(tokenId); |
| require(msg.sender == issuer || msg.sender == owner, "not authorized"); |
| _nonces[tokenId]++; |
| } |
|
|
| function permit( |
| address spender, |
| uint256 tokenId, |
| uint256 deadline, |
| bytes memory sig |
| ) external { |
| require(block.timestamp <= deadline, "permit expired"); |
| address owner = _requireOwned(tokenId); |
| bytes32 structHash = keccak256( |
| abi.encode( |
| PERMIT_TYPEHASH, |
| spender, |
| tokenId, |
| _nonces[tokenId]++, |
| deadline |
| ) |
| ); |
| bytes32 hash = _hashTypedDataV4(structHash); |
| address signer = ECDSA.recover(hash, sig); |
| require(signer == owner, "invalid permit signature"); |
| _approve(spender, tokenId, address(0), true); |
| } |
|
|
| function _update(address to, uint256 tokenId, address auth) internal virtual override returns (address from) { |
| from = super._update(to, tokenId, auth); |
| if (from != address(0)) { |
| _nonces[tokenId]++; |
| } |
| } |
|
|
| function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { |
| return interfaceId == 0x5604e225 || super.supportsInterface(interfaceId); |
| } |
| } |
|
|
