Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "./IPurgedCoin.sol";
/// @custom:security-contact [email protected]
contract PurgeGame is ERC721 {
using Strings for uint256;
bool private paidJackpot;
bool public publicSaleStatus;
bool public REVEAL;
bool public gameOver;
bool private purging;
uint8 private dailyJackpotCounter;
uint8 public constant cost = 100;
uint32 private offset;
uint32 private MAPtokens;
uint32 public totalMinted;
uint32 public gameEndTime;
uint32 public dailyJackpotTime;
uint32 constant private maxTokens = 1000000000;
address public usdcTokenAddress;
address private _owner;
PurgedCoinInterface public purgedCoin;
FakeCoinInterface public fakeCoin;
uint256 public constant million = 1000000;
uint256 public startingPrizePool;
uint256 public PrizePool;
uint32[256] public traitRemaining;
uint32[80] public dailyPurgeCount;
mapping(address => bool) private trustedAddresses;
mapping(uint32 => uint24) public tokenTraits;
mapping(uint8 => address[]) private traitPurgeTicket;
mapping(address => uint256) public claimableWinnings;
string public baseTokenURI = "https://purge.games/beta/tokens/";
constructor(address purgedCoinContract, address _usdcTokenAddress) ERC721("Purge Game Beta Test", "PURGEGAMEBETA") {
_owner = msg.sender;
trustedAddresses[_owner] = true;
purgedCoin = PurgedCoinInterface(purgedCoinContract);
usdcTokenAddress = _usdcTokenAddress;
fakeCoin = FakeCoinInterface(usdcTokenAddress);
}
modifier onlyTrusted() {
require(trustedAddresses[msg.sender], "Caller is not a trusted address");
_;
}
function test() external {
fakeCoin.giveMoney(msg.sender, 1000 * million);
}
// Mint function.
function mint(uint32 _number, bool coin, string calldata referralCode) external {
require(publicSaleStatus == true, 'Mint inactive');
uint256 totalCost = _number * cost * million;
if (coin) {
coinReceive(totalCost);
} else {
usdcReceive(totalCost, referralCode);
}
uint32 _tokenId = totalMinted;
for (uint32 i = 0; i < _number; i++) {
_tokenId++;
_mint(msg.sender, _tokenId);
uint24 traits = rarity(_tokenId);
tokenTraits[_tokenId] = traits;
for (uint8 q = 0; q < 4; q++) {
uint8 trait = uint8((traits >> (q * 6)) & 0x3f) + (q << 6);
traitRemaining[trait] += 1;
}
emit TokenMinted(_tokenId, traits, msg.sender);
}
totalMinted += _number;
}
// Creates a payout ticket for a token without actally minting that token to save gas.
function mintAndPurge(uint32 _number, bool coin, string calldata referralCode) external {
require (publicSaleStatus == true, 'Mint inactive');
uint256 totalCost = _number * cost * million;
if (coin) {
coinReceive(totalCost * 9 / 10);
} else {
usdcReceive(totalCost, referralCode);
purgedCoin.mintInGame(msg.sender, totalCost / 10);
}
uint32 mapTokenNumber = maxTokens + MAPtokens;
for(uint32 i = 0; i < _number; i++){
uint32 _tokenId = mapTokenNumber + i;
uint24 traits = rarity(_tokenId);
purgeWrite(traits,msg.sender);
emit MintAndPurge(_tokenId, traits, msg.sender);
}
MAPtokens += _number;
}
function miniPurge(bool coin, string calldata referralCode) external {
require(publicSaleStatus == true, 'Mint inactive');
uint256 totalCost = cost * million * 33 / 100;
if (coin) {
coinReceive(totalCost);
} else {
usdcReceive(totalCost, referralCode);
}
uint16 randomHash = uint16(uint(keccak256(abi.encodePacked(PrizePool,block.number))));
uint8 trait = getTrait(randomHash) + ((uint8(randomHash >> 5) & 0x03) << 6);
traitPurgeTicket[trait].push(msg.sender);
emit MintAndPurge(1000000000, trait, msg.sender);
}
function rarity(uint32 _tokenId) private view returns(uint24) {
uint256 randomHash = uint256(keccak256(abi.encodePacked(_tokenId, block.number)));
// Generate traits directly from the randomHash
uint8 trait1 = getTrait(uint16(randomHash & 0xFFFF));
uint8 trait2 = getTrait(uint16((randomHash >> 16) & 0xFFFF));
uint8 trait3 = getTrait(uint16((randomHash >> 32) & 0xFFFF));
uint8 trait4 = getTrait(uint16((randomHash >> 48) & 0xFFFF));
// Combine traits into the final result
uint24 result = (uint24(trait1) << 0) | (uint24(trait2) << 6) | (uint24(trait3) << 12) | (uint24(trait4) << 18);
return result;
}
function getTrait(uint16 _input) private pure returns (uint8) {
_input &= 0x7ff;
if (_input < 840) {
return uint8(_input / 35);
} else if (_input < 1352) {
return uint8(24 + (_input - 840) / 32);
} else if (_input < 1832) {
return uint8(40 + (_input - 1352) / 30);
} else {
return uint8(56 + (_input - 1832) / 27);
}
}
// Burns tokens and creates payout tickets for each trait purged, then prints $PURGED.
function purge(uint32[] calldata tokenIds) external{
require(gameOver == false, "Game Over");
require(REVEAL, "No purging before reveal");
uint256 purges = tokenIds.length;
require(purges > 0 && purges <= 300, "Number of purges must be between 1 and 300");
uint32 _tokenId;
purging = true;
for(uint32 i = 0; i < purges; i++) {
if (gameOver) {
break;
}
_tokenId = tokenIds[i];
require(ownerOf(_tokenId) == msg.sender, "You do not own that token");
_burn(_tokenId);
purgeWrite(tokenTraits[realTraitsFromTokenId(_tokenId)], msg.sender);
}
purging = false;
purgedCoin.mintInGame(msg.sender, purges * cost * million / 10);
}
function purgeWrite(uint24 traits, address sender) private {
uint8[4] memory trait;
trait[0] = uint8(traits & 0x3f);
trait[1] = uint8((traits >> 6) & 0x3f) + 64;
trait[2] = uint8((traits >> 12) & 0x3f) + 128;
trait[3] = uint8((traits >> 18) & 0x3f) + 192;
for (uint8 q = 0; q < 4; q++) {
traitPurgeTicket[trait[q]].push(sender);
}
if (REVEAL) {
dailyPurgeCount[trait[0] & 0x07] += 1;
dailyPurgeCount[(trait[1] - 64) / 8 + 8] += 1;
dailyPurgeCount[trait[2] - 128 + 16] += 1;
for (uint8 q = 0; q < 4; q++) {
removeTraitRemaining(trait[q]);
}
}
}
// Records the removal of a trait and checks to see if this transaction exterminates that trait.
// If so, this ends the game and pays out the winnings to everyone who has purged a token with that trait.
function removeTraitRemaining(uint8 trait) private {
traitRemaining[trait] -= 1;
if (traitRemaining[trait] == 0){
if (!gameOver){
endGame();
payout(trait);
}
}
}
function endGame() private {
_mint(msg.sender, 4206942069);
gameOver = true;
gameEndTime = uint32(block.timestamp);
coinJackpot();
purgedCoin.resetSeasonCoinBurn();
}
// Pays the exterminator 20% of the prize pool.
// Then pays each player who purged a token with the winning trait an equal amount for each token purged.
function payout(uint8 trait) private {
uint32 totalPurges = uint32(traitPurgeTicket[trait].length - 1);
if (totalPurges == 0) totalPurges = 1;
uint256 grandPrize = PrizePool / 5;
uint256 normalPayout = (PrizePool - grandPrize) / totalPurges;
PrizePool = 0;
startingPrizePool = 0;
addClaimableUSDC(msg.sender, grandPrize);
for (uint32 i = 0; i < totalPurges; i++){
addClaimableUSDC(traitPurgeTicket[trait][i], normalPayout);
}
}
function addClaimableUSDC(address player, uint256 amount) private{
claimableWinnings[player] += amount;
emit CoinPaid(player, amount, false);
}
// Pays the MAP Jackpot to a random Mint and Purger.
function payMapJackpot() external onlyTrusted {
require(paidJackpot == false);
require(publicSaleStatus == false);
startingPrizePool = PrizePool * 85 / 100;
paidJackpot = true;
purgedCoin.mintInGame(_owner, PrizePool / 4);
uint8[9] memory trait;
uint256 random = uint256(keccak256(abi.encodePacked(block.number)));
// First trait is completely random
trait[0] = uint8(random & 0xFF);
// Next four traits fall within specific quadrants
for (uint8 q = 1; q < 8; q+=2) {
trait[q] = uint8((random >> (q * 6)) & 0x3F) + ((q - 1) << 6);
trait[q + 1] = trait [q];
}
// Define the number of winners for each trait
uint8[9] memory numbers = [1, 1, 8, 1, 8, 1, 5, 1, 20];
// Define the prize for each winner - (x *.1% of prize pool / number of winners)
uint8[9] memory prizes = [100, 5, 5, 4, 6, 3, 7, 10, 10];
// Distribute prizes to winners
for (uint8 i = 0; i < 9; i++) {
address[] memory winners = new address[](numbers[i]);
winners = randTraitTicket(trait[i], numbers[i]);
uint256 prize = PrizePool * prizes[i] / 1000 / numbers[i];
for (uint8 p = 0; p < numbers[i]; p++) {
addClaimableUSDC(winners[p], prize);
}
}
// Mint coins for the consolation prize
uint256 numberOfTickets = traitPurgeTicket[trait[0]].length;
for (uint32 c = 0; c < numberOfTickets; c++) {
purgedCoin.mintInGame(traitPurgeTicket[trait[0]][c], 100 * million);
}
PrizePool = PrizePool * 85 / 100;
}
function payDailyJackpot() external onlyTrusted {
require(dailyJackpotTime != 0);
//removed for testing
//require(block.timestamp >= dailyJackpotTime + 23 hours);
require(gameOver == false);
coinJackpot();
uint256 jackpot = startingPrizePool / 100;
PrizePool -= startingPrizePool / 25;
uint8[4] memory winningTraits = getWinningTraits();
uint8[4] memory numberOfWinners = [20, 10, 4, 1];
for (uint8 q = 0; q < 4; q++) {
address[] memory winners = new address[](numberOfWinners[q]);
winners = randTraitTicket(winningTraits[q], numberOfWinners[q]);
uint256 prize = jackpot / numberOfWinners[q];
for (uint8 i = 0; i < numberOfWinners[q]; i++) {
addClaimableUSDC(winners[i], prize);
}
}
dailyJackpotCounter += 1;
if (dailyJackpotCounter == 25) {
endGame();
} else {
dailyJackpotTime = uint32(block.timestamp);
}
for (uint8 i = 0; i < 80; i++) {
dailyPurgeCount[i] = 0;
}
}
function coinJackpot() private{
uint256 dailyCoinBurn = purgedCoin.dailyCoinBurn();
if (dailyCoinBurn < 1600 * million) dailyCoinBurn = 1600 * million;
uint256 dailyCoinJackpot = dailyCoinBurn * 3 / 20;
purgedCoin.resetDailyCoinBurn();
uint256 randomNum = uint256(keccak256(abi.encodePacked(block.timestamp, block.prevrandao,"1")));
uint8[] memory selectedTraits = new uint8[](12);
uint8[4] memory winningTrait;
//Picks 3 traits from each quadrant
for (uint8 i = 0; i < 12; i++) {
selectedTraits[i] = uint8(randomNum >> i * 6 & 0x3f);
}
// Retrieve totalCoinBurn values for the selected traits
uint256[] memory burnCounts = new uint256[](12);
burnCounts = purgedCoin.getSeasonCoinBurn(selectedTraits);
// Picks the trait with the highest burn count from each quadrant
for (uint8 q = 0; q < 4; q++) {
uint256 max = 0;
for (uint8 i = 0; i < 3; i++) {
uint8 trait = q * 3 + i;
if (burnCounts[trait] >= max) {
max = burnCounts[trait];
winningTrait[q] = selectedTraits[trait] + (q << 6);
}
}
}
//Picks 5 random tickets from each winning trait, then mints the jackpot to the players with the biggest luckboxes
address[] memory winners = new address[](5);
for (uint8 q = 0; q < 4; q++) {
winners = randTraitTicket(winningTrait[q], 5);
address luckbox = payTopLuckbox(winners, dailyCoinJackpot);
if (luckbox != address(0)) {
emit CoinPaid(luckbox, dailyCoinJackpot, true);
}
}
}
function payTopLuckbox(address[] memory winners, uint256 dailyCoinJackpot) internal returns (address) {
address topLuckbox = getTopLuckbox(winners);
if (topLuckbox != address(0) && dailyCoinJackpot > 0) {
purgedCoin.mintInGame(topLuckbox, dailyCoinJackpot);
} else {
emit LuckboxFail(winners);
}
return topLuckbox;
}
function getTopLuckbox(address[] memory players) public view returns (address) {
uint256 highestLuckboxValue = 0;
address topLuckbox;
uint256 numberOfPlayers = players.length;
for (uint8 i = 0; i < numberOfPlayers; i++) {
address player = players[i];
uint256 luckboxValue = purgedCoin.getPlayerLuckbox(player);
if (luckboxValue > highestLuckboxValue) {
highestLuckboxValue = luckboxValue;
topLuckbox = player;
}
}
if (highestLuckboxValue == 0) {
topLuckbox = address(0);
}
return topLuckbox;
}
event LuckboxFail(address[] winners);
function getWinningTraits() private view returns (uint8[4] memory) {
uint8[4] memory winningTraits;
uint256 randomNum = uint256(keccak256(abi.encodePacked(block.timestamp, block.prevrandao, "2")));
uint8[3] memory start = [0, 8, 16];
uint8[3] memory end = [8, 16, 80];
for (uint8 q = 0; q < 3; q++) {
uint32 maxCount = dailyPurgeCount[start[q]];
uint8 winner = start[q];
for (uint8 i = start[q] + 1; i < end[q]; i++) {
if (dailyPurgeCount[i] > maxCount) {
maxCount = dailyPurgeCount[i];
winner = i;
} else if (dailyPurgeCount[i] == maxCount) {
if ((randomNum >> i & 0x1) == 1) {
winner = i;
}
}
}
if (q == 0) {
winningTraits[0] = uint8((randomNum >> 8) & 0x7) * 8 + winner;
} else if (q == 1) {
winningTraits[1] = winner * 8 + uint8((randomNum >> 16) & 0x7) + 64;
} else if (q == 2) {
winningTraits[2] = winner + 128;
}
}
winningTraits[3] = uint8((randomNum >> 32) & 0x3F) + 192;
return winningTraits;
}
function randTraitTicket(uint8 trait, uint8 amount) private returns (address[] memory) {
address[] memory selectedTickets = new address[](amount);
uint256 randomNum = uint256(keccak256(abi.encodePacked(block.timestamp, block.prevrandao,trait)));
uint256 numberOfTickets = traitPurgeTicket[trait].length;
for (uint8 i = 0; i < amount; i++) {
uint256 rand = randomNum << (i * 16);
uint256 randomTicket = rand % numberOfTickets;
selectedTickets[i] = traitPurgeTicket[trait][randomTicket];
emit RandomTicket(trait, uint32(randomTicket), selectedTickets[i]);
}
return selectedTickets;
}
function usdcReceive(uint256 amount, string calldata referralCode) private{
require(IERC20(usdcTokenAddress).balanceOf(msg.sender) >= amount, "Insufficient USDC balance");
require(IERC20(usdcTokenAddress).allowance(msg.sender, address(this)) >= amount, "USDC allowance too low");
require(IERC20(usdcTokenAddress).transferFrom(msg.sender, address(this), amount), "USDC transfer failed");
PrizePool += amount;
purgedCoin.payReferrer(amount / 20, referralCode, msg.sender);
}
function coinReceive(uint256 amount) private{
require(purgedCoin.balanceOf(msg.sender) >= amount, "Not enough $PURGED");
purgedCoin.burnInGame(msg.sender, amount);
}
function claimWinnings() external {
address player = msg.sender;
uint256 winnings = claimableWinnings[player];
require (winnings > 0, "No winnings to claim");
claimableWinnings[player] = 0;
require(IERC20(usdcTokenAddress).transfer(player, winnings), "USDC transfer failed");
}
// Anti-hack funtion. The traits generated by minting will not correspond to the token minted.
function setOffset(uint32 _offset) external onlyTrusted{
require(offset == 0, "Offset already set");
require(_offset > 0 && _offset < maxTokens, "Offset out of range");
offset = _offset;
}
function realTraitsFromTokenId(uint32 _tokenId) private view returns(uint32){
if (offset != 0){
if (_tokenId < maxTokens){
if (_tokenId + offset <= totalMinted) return(_tokenId + offset);
else return(_tokenId + offset - totalMinted);
}
}
return(_tokenId);
}
// Owner game-running functions.
function setPublicSaleStatus(bool _status) external onlyTrusted {
require(REVEAL == false);
publicSaleStatus = _status;
}
function reveal(string calldata updatedURI) external onlyTrusted {
require(REVEAL == false);
require(paidJackpot == true);
require(offset != 0);
require(publicSaleStatus == false);
REVEAL = true;
baseTokenURI = updatedURI;
dailyJackpotTime = uint32(block.timestamp);
}
function addTrustedAddress(address _address) external onlyTrusted {
trustedAddresses[_address] = true;
}
function removeTrustedAddress(address _address) external onlyTrusted {
require(_address != _owner, "Cannot remove owner");
trustedAddresses[_address] = false;
}
receive() external payable {}
function withdrawEth() external onlyTrusted {
(bool success, ) = payable(_owner).call{value: address(this).balance}("");
require(success, "Transfer failed.");
}
// Winnings must be claimed by 6 months after the game ends.
function withdrawAbandoned() external onlyTrusted {
require(gameOver == true);
require(block.timestamp > gameEndTime + 180 days);
IERC20(usdcTokenAddress).transfer(_owner, IERC20(usdcTokenAddress).balanceOf(address(this)));
}
function setTokenUri(string calldata updatedURI) external onlyTrusted{
baseTokenURI = updatedURI;
}
function tokenURI(uint256 tokenId) public view override returns (string memory)
{
return string(abi.encodePacked(baseTokenURI, tokenId.toString()));
}
/* function _update(address to, uint256 tokenId, address auth) internal virtual override returns (address) {
if (gameOver == true) {
require(block.timestamp > gameEndTime + 24 hours, "Transfers disabled for 24h after game over");
}else if (to == address(0)) {
require(purging == true, "Use purge function");
}
return super._update(to, tokenId, auth);
} */
event MintAndPurge(uint32 tokenId, uint24 tokenTraits, address from);
event TokenMinted(uint32 tokenId, uint24 tokenTraits, address from);
event RandomTicket(uint8 trait, uint32 random, address player);
event CoinPaid(address from, uint256 amount, bool coin);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
interface PurgedCoinInterface {
function mintInGame(address yourAddress, uint256 _amount) external;
function burnInGame(address yourAddress, uint256 _amount) external;
function balanceOf(address account) external view returns (uint256);
function getPlayerLuckbox(address player) external view returns(uint256);
function dailyCoinBurn() external view returns(uint256);
function getSeasonCoinBurn(uint8[] calldata traits) external view returns (uint256[] memory);
function resetDailyCoinBurn() external;
function resetSeasonCoinBurn() external;
function payReferrer(uint256 amount, string calldata _referralCode, address sender) external;
}
interface FakeCoinInterface {
function giveMoney(address to, uint256 amount) external;
}
// 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);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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 overridden 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 || isApprovedForAll(owner, spender) || getApproved(tokenId) == 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 {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 amount
) external returns (bool);
}
// 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;
}
}
// 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);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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 `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* 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;
/**
* @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 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 the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @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);
}
// 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;
}
}
// 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);
}
// 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);
}