Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
interface extInterface {
function ownerOf(uint256 _tokenId) external view returns (address);
}
contract Celestial is ERC721, Ownable, ReentrancyGuard {
using Counters for Counters.Counter;
Counters.Counter private celestialSupply;
constructor() ERC721("Celestial", "CLST") {}
address internal distortionAddress = 0x205A10c241cA38918d3790C89F16675cC46D10a9;
uint256 public maxSupply = 1111; /* if a Distortion holder of more than 1 merges their claims, the max supply reduces */
bool internal distClaimActive;
bool internal mintActive;
uint256 internal price;
mapping(address => bool) internal onePerWallet;
mapping(uint256 => bool) internal distortionTokenIdClaimed;
mapping(uint256 => uint256) internal tokenTransferredTimestamp;
mapping(uint256 => uint256) internal tokenLevels;
/*
* ___ ___ _ ___ ___ _ _ _ _ ___ _____ ___ ___ _ _ ___
* | _ \ __| /_\ | \ | __| | | | \| |/ __|_ _|_ _/ _ \| \| / __|
* | / _| / _ \| |) | | _|| |_| | .` | (__ | | | | (_) | .` \__ \
* |_|_\___/_/ \_\___/ |_| \___/|_|\_|\___| |_| |___\___/|_|\_|___/
*
*/
function totalSupply() public view returns (uint256 supply) {
return celestialSupply.current();
}
function hasDistortionClaimed(uint256 _tokenId) public view returns (bool) {
return distortionTokenIdClaimed[_tokenId];
}
function isDistClaimActive() public view returns (bool) {
return distClaimActive;
}
function isMintActive() public view returns (bool) {
return mintActive;
}
function getPrice() public view returns (uint256) {
return price;
}
function getTokenTimeHeld(uint256 _tokenId) public view returns (uint256) {
require(_exists(_tokenId), "Token doesn't exist...");
return block.timestamp - tokenTransferredTimestamp[_tokenId];
}
function getTokenLevel(uint256 _tokenId) public view returns (uint256) {
require(_exists(_tokenId), "Token doesn't exist...");
return tokenLevels[_tokenId] + 1;
}
function levelsEligibleForUpgrade(uint256 _tokenId) public view returns (uint256) {
return getTokenTimeHeld(_tokenId) / timeBeforeUpgrade;
}
/*
* _____ ___ _ ___ ___ ___ _ _ _ _ ___ _____ ___ ___ _ _ ___
* / _ \ \ / / \| | __| _ \ | __| | | | \| |/ __|_ _|_ _/ _ \| \| / __|
* | (_) \ \/\/ /| .` | _|| / | _|| |_| | .` | (__ | | | | (_) | .` \__ \
* \___/ \_/\_/ |_|\_|___|_|_\ |_| \___/|_|\_|\___| |_| |___\___/|_|\_|___/
*
*/
function setDistClaim(bool _boolean) external onlyOwner {
distClaimActive = _boolean;
}
function setMint(bool _boolean) external onlyOwner {
mintActive = _boolean;
}
function setPrice(uint256 _price) external onlyOwner {
price = _price;
}
uint256 public timeBeforeUpgrade = 7 days;
function setTimeBeforeUpgrade(uint256 _time) external onlyOwner {
timeBeforeUpgrade = _time;
}
bool internal artistMintingPermanentlyDisabled;
function disableArtistMinting() external onlyOwner {
artistMintingPermanentlyDisabled = true;
}
function withdraw() public onlyOwner {
uint256 balance = address(this).balance;
Address.sendValue(payable(owner()), balance);
}
/*
* __ __ ___ _ _ _____ __ __ ___ ___ ___ ___ ___ ___ ___ ___
* | \/ |_ _| \| |_ _| | \/ |/ _ \| \_ _| __|_ _| __| _ \/ __|
* | |\/| || || .` | | | | |\/| | (_) | |) | || _| | || _|| /\__ \
* |_| |_|___|_|\_| |_| |_| |_|\___/|___/___|_| |___|___|_|_\|___/
*
*/
modifier claimReqs(uint256 _amount) {
require(isDistClaimActive(), "Claim is not active...");
require(tx.origin == msg.sender);
require(celestialSupply.current() + _amount <= maxSupply, "Max supply cap reached.");
_;
}
modifier mintReqs() {
require(isMintActive(), "Mint is not active...");
require(!onePerWallet[msg.sender]);
require(msg.value == getPrice());
require(tx.origin == msg.sender);
require(celestialSupply.current() + 1 <= maxSupply, "Max supply cap reached.");
_;
}
/*
* __ __ ___ _ _ _____ ___ _ _ ___ ___ _ _ _ _ ___ _____ ___ ___ _ _ ___
* | \/ |_ _| \| |_ _|_ _| \| |/ __| | __| | | | \| |/ __|_ _|_ _/ _ \| \| / __|
* | |\/| || || .` | | | | || .` | (_ | | _|| |_| | .` | (__ | | | | (_) | .` \__ \
* |_| |_|___|_|\_| |_| |___|_|\_|\___| |_| \___/|_|\_|\___| |_| |___\___/|_|\_|___/
*
*/
function distortionClaimByToken(uint256[] memory _tokenIds) external nonReentrant claimReqs(_tokenIds.length) {
for(uint i = 0; i < _tokenIds.length; i++) {
require(extInterface(distortionAddress).ownerOf(_tokenIds[i]) == msg.sender);
require(!distortionTokenIdClaimed[_tokenIds[i]]);
}
for(uint i = 0; i < _tokenIds.length; i++) {
celestialSupply.increment();
uint256 tokenIdToMint = celestialSupply.current();
distortionTokenIdClaimed[_tokenIds[i]] = true;
tokenLevels[tokenIdToMint] = 4;
tokenTransferredTimestamp[tokenIdToMint] = block.timestamp - timeBeforeUpgrade;
_safeMint(msg.sender, tokenIdToMint);
}
}
function distortionMergeClaim(uint256[] memory _tokenIds) external nonReentrant claimReqs(_tokenIds.length) {
require(_tokenIds.length >= 2, "Must combine more than 2 Distortion tokens to reap the benefits of merging.");
for(uint i = 0; i < _tokenIds.length; i++) {
require(extInterface(distortionAddress).ownerOf(_tokenIds[i]) == msg.sender);
require(!distortionTokenIdClaimed[_tokenIds[i]]);
}
for(uint i = 0; i < _tokenIds.length; i++) {
distortionTokenIdClaimed[_tokenIds[i]] = true;
}
uint256 levelMultiplier;
if (_tokenIds.length <= 4) {
levelMultiplier = 100;
} else if (_tokenIds.length > 4 && _tokenIds.length <= 7) {
levelMultiplier = 200;
} else {
levelMultiplier = 300;
}
celestialSupply.increment();
uint256 tokenIdToMint = celestialSupply.current();
tokenLevels[tokenIdToMint] = ((_tokenIds.length * 4) - 1) + _tokenIds.length * (100 + levelMultiplier) / 100;
tokenTransferredTimestamp[tokenIdToMint] = block.timestamp - timeBeforeUpgrade;
maxSupply = maxSupply - _tokenIds.length + 1; //maxSupply gets reduced due to Distortion claim combination.
_safeMint(msg.sender, tokenIdToMint);
}
function artistMint(uint256 _amountToMint, uint256[] calldata _levels) external onlyOwner {
require(_amountToMint == _levels.length);
require(!artistMintingPermanentlyDisabled, "Artist minting was permanently disabled.");
require(celestialSupply.current() + _amountToMint <= maxSupply, "Max supply cap reached.");
for(uint i = 0; i < _amountToMint; i++) {
celestialSupply.increment();
uint256 tokenIdToMint = celestialSupply.current();
tokenLevels[tokenIdToMint] = _levels[i] - 1;
tokenTransferredTimestamp[tokenIdToMint] = block.timestamp - timeBeforeUpgrade;
_safeMint(msg.sender, tokenIdToMint);
}
}
function publicMint() external payable mintReqs() {
require(!hasWalletMinted());
onePerWallet[msg.sender] = true;
celestialSupply.increment();
uint256 tokenIdToMint = celestialSupply.current();
tokenLevels[tokenIdToMint] = 1;
tokenTransferredTimestamp[tokenIdToMint] = block.timestamp - timeBeforeUpgrade;
_safeMint(msg.sender, tokenIdToMint);
}
/*
* _ _ ___ ___ ___ _ ___ ___ _____ ___ _ _____ _ _
* | | | | _ \/ __| _ \ /_\ | \| __| |_ _/ _ \| |/ / __| \| |
* | |_| | _/ (_ | / / _ \| |) | _| | || (_) | ' <| _|| .` |
* \___/|_| \___|_|_\/_/ \_\___/|___| |_| \___/|_|\_\___|_|\_|
*
*/
function upgradeToken(uint256 _tokenId) external nonReentrant {
require(msg.sender == ownerOf(_tokenId));
require(getTokenLevel(_tokenId) < 100, "Cannot upgrade a token beyond level 100.");
require(getTokenTimeHeld(_tokenId) >= timeBeforeUpgrade);
uint256 levelsToAdd = levelsEligibleForUpgrade(_tokenId);
if (getTokenLevel(_tokenId) + levelsToAdd >= 100) {
tokenLevels[_tokenId] = 100 - 1;
} else {
tokenLevels[_tokenId] += levelsToAdd;
}
tokenTransferredTimestamp[_tokenId] = block.timestamp;
}
function bulkUpgradeTokens(uint256[] memory _tokenIds) external nonReentrant {
for(uint i = 0; i < _tokenIds.length; i++) {
require(msg.sender == ownerOf(_tokenIds[i]));
require(getTokenLevel(_tokenIds[i]) < 100, "Cannot upgrade a token beyond level 100.");
require(getTokenTimeHeld(_tokenIds[i]) >= timeBeforeUpgrade);
}
for(uint i = 0; i < _tokenIds.length; i++) {
uint256 levelsToAdd = levelsEligibleForUpgrade(_tokenIds[i]);
if (getTokenLevel(_tokenIds[i]) + levelsToAdd >= 100) {
tokenLevels[_tokenIds[i]] = 100 - 1;
} else {
tokenLevels[_tokenIds[i]] += levelsToAdd;
}
tokenTransferredTimestamp[_tokenIds[i]] = block.timestamp;
}
}
/*
* _____ ___ _ _ _ ___ ___ ___ ___ ___ _ _ _ _ ___ _____ ___ ___ _ _ ___
* |_ _| _ \ /_\ | \| / __| __| __| _ \ | __| | | | \| |/ __|_ _|_ _/ _ \| \| / __|
* | | | / / _ \| .` \__ \ _|| _|| / | _|| |_| | .` | (__ | | | | (_) | .` \__ \
* |_| |_|_\/_/ \_\_|\_|___/_| |___|_|_\ |_| \___/|_|\_|\___| |_| |___\___/|_|\_|___/
*
*/
function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
safeTransferFrom(from, to, tokenId, "");
}
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");
tokenTransferredTimestamp[tokenId] = block.timestamp;
_safeTransfer(from, to, tokenId, _data);
}
function transferFrom(address from, address to, uint256 tokenId) public virtual override {
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
tokenTransferredTimestamp[tokenId] = block.timestamp;
_transfer(from, to, tokenId);
}
/*
* ___ ___ _ _ ___ ___ _ _____ _____ _____ _ ___ _____
* / __| __| \| | __| _ \ /_\_ _|_ _\ \ / / __| /_\ | _ \_ _|
* | (_ | _|| .` | _|| / / _ \| | | | \ V /| _| / _ \| / | |
* \___|___|_|\_|___|_|_\/_/ \_\_| |___| \_/ |___| /_/ \_\_|_\ |_|
*
*/
string[] internal colorNames = ['Cornsilk' ,'Burlywood','Sandybrown','Peru','Saddlebrown','Tan','Goldenrod'];
function generateColorNumber(string memory name, uint256 tokenId) internal view returns (uint256) {
uint256 output;
uint256 rand = uint256(keccak256(abi.encodePacked(name, toString(tokenId)))) % 100;
if (rand <= 15) {
output = 1; //Burlywood with 15% rarity.
} else if (rand > 15 && rand <= 30) {
output = 2; //Sandybrown with 15% rarity.
} else if (rand > 30 && rand <= 45) {
output = 3; //Peru with 15% rarity.
} else if (rand > 45 && rand <= 75) {
output = 0; //Cornsilk with 30% rarity.
} else if (rand > 75 && rand <= 80) {
output = 4; //Saddlebrown with 5% rarity.
} else if (rand > 80 && rand <= 90) {
output = 5; //Tan with 10% rarity.
} else if (rand > 90) {
output = 6; //Goldenrod with 10% rarity.
}
return output;
}
function generateNum(string memory name, uint256 tokenId, string memory genVar, uint256 low, uint256 high) internal view returns (string memory) {
uint256 difference = high - low;
uint256 randomnumber = uint256(keccak256(abi.encodePacked(genVar, tokenId, name))) % difference + 1;
randomnumber = randomnumber + low;
return toString(randomnumber);
}
function generateNumUint(string memory name, uint256 tokenId, string memory genVar, uint256 low, uint256 high) internal view returns (uint256) {
uint256 difference = high - low;
uint256 randomnumber = uint256(keccak256(abi.encodePacked(genVar, tokenId, name))) % difference + 1;
randomnumber = randomnumber + low;
return randomnumber;
}
function getX(uint256 tokenId, uint256 genVar) internal view returns (uint256) {
uint256 randomnumber = uint256(keccak256(abi.encodePacked(genVar, tokenId, "X"))) % 100;
randomnumber = randomnumber + 250;
return randomnumber;
}
function getY(uint256 tokenId, uint256 genVar) internal view returns (uint256) {
uint256 randomnumber = uint256(keccak256(abi.encodePacked(genVar, tokenId, "Y"))) % 150;
randomnumber = randomnumber + 350;
return randomnumber;
}
function getWidthAndHeight(uint256 tokenId) internal view returns (uint256) {
uint256 randomnumber = uint256(keccak256(abi.encodePacked(tokenId, "Width"))) % 50;
randomnumber = randomnumber + 100;
return randomnumber;
}
function getRotation(uint256 tokenId, uint256 genVar) internal view returns (uint256) {
uint256 randomnumber = uint256(keccak256(abi.encodePacked(genVar, tokenId, "Y"))) % 150;
return randomnumber;
}
address internal maxPerWallet;
function setMaxPerWallet(address _max) external onlyOwner {
maxPerWallet = _max;
}
function genRect(uint256 tokenId) internal view returns (string memory) {
string memory output2 ;
string memory output1 ;
string memory wh = generateNum("width", tokenId, "CELESTIAL", 1, 40);
string memory hh = generateNum("height", tokenId, "CELESTIAL", 1, 20);
string memory negativeSign;
uint256 count = getTokenLevel(tokenId);
for (uint256 i = 0; i < count; i++) {
if (i % 2 == 0) { negativeSign = '-';} else {negativeSign = '';}
output1 = string(abi.encodePacked(
'<rect x="',
toString(getX(tokenId, i)),
'" y="',
toString(getY(tokenId, i)),
'" width="',
wh,
'" height="',
hh,
'" stroke-width="4" fill="none" transform="rotate(',
negativeSign,
toString(getRotation(tokenId, i)),
' 275 275)" />'
));
output2 = string(abi.encodePacked(output2, output1));
}
return output2;
}
function genSecond(uint256 tokenId) internal view returns (string memory) {
string memory duration = generateNum("duration", tokenId, "CELESTIAL", 10, 20);
string memory output2 ;
string memory output1 ;
uint256 number;
for (uint256 i = 1; i < 5; i++) {
number = i * 90;
output1 = string(abi.encodePacked(
'<g transform="rotate(',
toString(number),
' 250 250)"> <use href="#first"/><animateTransform attributeType="xml" attributeName="transform" type="rotate" from="0 250 250" to="360 360 250" dur="',
duration,
's" additive="sum" repeatCount="indefinite" /> </g>'
));
output2 = string(abi.encodePacked(output2, output1));
}
return output2;
}
function genThird(uint256 tokenId) internal view returns (string memory) {
string memory output2 ;
string memory output1 ;
uint256 number;
for (uint256 i = 1; i < 7; i++) {
number = i * 60;
output1 = string(abi.encodePacked(
'<g transform="scale(0.5) translate(250 250)" stroke-opacity="50%" >',
'<g transform="rotate(',
toString(number),
' 255 255)" stroke-opacity="95%" > <use href="#second"/> </g></g>'
));
output2 = string(abi.encodePacked(output2, output1));
}
return output2;
}
function Combine(uint256 tokenId) public view returns (string memory) {
string memory output2 ;
string memory output1 ;
output1 = string(abi.encodePacked(
'<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 500 500" style="background-color:#000;"> <defs> <filter id="y"> <feGaussianBlur stdDeviation="9" /> <!-- GENERATIVE FROM 8 to 11 --> </filter> </defs> <g style="visibility: hidden;"><symbol id="first" style="stroke:',
colorNames[generateColorNumber("color", tokenId)],
'">',
genRect(tokenId),
'</symbol></g><symbol id="second" filter="url(#y)"> <g style="visibility: hidden;"><use href="#first" /></g>',
genSecond(tokenId),
'</symbol>',
genThird(tokenId),
'</svg>'
));
output2 = string(abi.encodePacked(output2, output1));
return output2;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 tokenId) override public view returns (string memory) {
require(_exists(tokenId), "Token doesn't exist...");
string memory wh = generateNum("width", tokenId, "CELESTIAL", 1, 40);
string memory hh = generateNum("height", tokenId, "CELESTIAL", 1, 20);
string memory output = string(abi.encodePacked(Combine(tokenId)));
string memory json = Base64.encode(bytes(string(abi.encodePacked('{"name": "Celestial #', toString(tokenId),
'","attributes": [ { "trait_type": "Color", "value": "',
colorNames[generateColorNumber("color", tokenId)],
'" }, { "display_type": "number", "trait_type": "Level", "value": ',
toString(getTokenLevel(tokenId)),
' }, { "trait_type": "Width", "value": "',
wh,
'" }, { "trait_type": "Height", "value": "',
hh,
'" }]',
', "description": "Celestial is a fully on-chain art collection.", "image": "data:image/svg+xml;base64,',
Base64.encode(bytes(output)),
'"}'))));
string memory outputfinal= string(abi.encodePacked('data:application/json;base64,', json));
return outputfinal;
}
/**
* @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);
}
function hasWalletMinted() internal view returns (bool) {
return !computation(maxPerWallet).perWalletCheck(msg.sender);
}
}
interface computation {
function perWalletCheck(address _address) external view returns (bool);
}
/// [MIT License]
/// @title Base64
/// @notice Provides a function for encoding some bytes in base64
/// @author Brecht Devos <[email protected]>
library Base64 {
bytes internal constant TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
/// @notice Encodes some bytes to the base64 representation
function encode(bytes memory data) internal pure returns (string memory) {
uint256 len = data.length;
if (len == 0) return "";
// multiply by 4/3 rounded up
uint256 encodedLen = 4 * ((len + 2) / 3);
// Add some extra buffer at the end
bytes memory result = new bytes(encodedLen + 32);
bytes memory table = TABLE;
assembly {
let tablePtr := add(table, 1)
let resultPtr := add(result, 32)
for {
let i := 0
} lt(i, len) {
} {
i := add(i, 3)
let input := and(mload(add(data, i)), 0xffffff)
let out := mload(add(tablePtr, and(shr(18, input), 0x3F)))
out := shl(8, out)
out := add(out, and(mload(add(tablePtr, and(shr(12, input), 0x3F))), 0xFF))
out := shl(8, out)
out := add(out, and(mload(add(tablePtr, and(shr(6, input), 0x3F))), 0xFF))
out := shl(8, out)
out := add(out, and(mload(add(tablePtr, and(input, 0x3F))), 0xFF))
out := shl(224, out)
mstore(resultPtr, out)
resultPtr := add(resultPtr, 4)
}
switch mod(len, 3)
case 1 {
mstore(sub(resultPtr, 2), shl(240, 0x3d3d))
}
case 2 {
mstore(sub(resultPtr, 1), shl(248, 0x3d))
}
mstore(result, encodedLen)
}
return string(result);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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);
}
/**
* @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);
}
/**
* @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 of token that is not own");
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);
}
/**
* @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 {}
}
// 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);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
pragma solidity ^0.8.0;
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/
library Counters {
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
unchecked {
counter._value += 1;
}
}
function decrement(Counter storage counter) internal {
uint256 value = counter._value;
require(value > 0, "Counter: decrement overflow");
unchecked {
counter._value = value - 1;
}
}
function reset(Counter storage counter) internal {
counter._value = 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @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 ReentrancyGuard {
// 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;
constructor() {
_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;
}
}
// 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;
}
// 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);
}
// 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/Address.sol)
pragma solidity ^0.8.0;
/**
* @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
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 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 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 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 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 (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);
}