Contract Source Code:
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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import "GoatLibrary.sol";
contract GoatSoup is ERC721, Ownable {
using ECDSA for bytes32;
uint256 private constant GS_PRICE = 0.08 ether;
uint256 private constant GS_PRIVATE_MAX = 3500;
uint256 private constant GS_SALE_MAX = 3744;
uint256 private constant GS_AIRDROP = 100;
address private constant GS_TEAM = 0xfa5d05Df712B059B74cCeFe4084785BE7f2ea1B8;
mapping(string => bool) private _nonces;
address private _signer = 0x818cDA2bA9CbC2dE202105E08dF37a26793f96A1;
uint256 private _reserveCounter;
uint256 private _presaleCounter;
uint256 private _publicCounter;
mapping(address => bool) public purchasedPresales;
uint256 public currentSupply;
bool public saleLive = false;
bool public presaleLive = false;
struct Attribute {
string name;
string attr_type;
string svgPath;
uint256 pixelCount;
}
mapping(uint256 => Attribute[]) _attributes;
mapping(uint256 => uint256) _tokens;
uint256 _nonce;
constructor() ERC721("Goat Soup", "GSOUP") { }
function verifyPublicMint(address sender, uint256 amount, string memory nonce, bytes memory signature) private view returns(bool) {
bytes32 hash = keccak256(abi.encodePacked(sender, amount, nonce));
return _signer == hash.recover(signature);
}
function verify(address sender, bytes memory signature) private view returns(bool) {
bytes32 hash = keccak256(abi.encodePacked(sender));
return _signer == hash.recover(signature);
}
function mint(uint256 amount, string memory nonce, bytes memory signature) external payable {
require(saleLive, "NOT_RELEASED");
require(totalSupply() < GS_SALE_MAX, "SOLD_OUT");
require(amount <= 2, "MAX_PER_TX_SALE");
require(!_nonces[nonce], "NONCE_USED");
require(verifyPublicMint(msg.sender, amount, nonce, signature), "INVALID_TRANSACTION");
require(_publicCounter + amount <= GS_SALE_MAX - _presaleCounter - GS_AIRDROP, "MAX_PUBLIC_SALE");
require(msg.value * amount >= GS_PRICE, "INSUFFICIENT_ETH_SENT");
_nonces[nonce] = true;
_publicCounter += amount;
for(uint256 i = 0; i < amount; i++) {
internalMint(msg.sender);
}
}
function presale(bytes memory signature) external payable {
require(presaleLive, "NOT_RELEASED");
require(totalSupply() < GS_SALE_MAX, "SOLD_OUT");
require(_presaleCounter < GS_PRIVATE_MAX, "MAX_PRIVATE_SALE");
require(!purchasedPresales[msg.sender], "MAX_PER_PRESALE");
require(verify(msg.sender, signature), "INVALID_TRANSACTION");
require(msg.value >= GS_PRICE, "INSUFFICIENT_ETH_SENT");
purchasedPresales[msg.sender] = true;
_presaleCounter++;
internalMint(msg.sender);
}
function reserveGoatSoup(address[] calldata _receivers) external onlyOwner {
require(totalSupply() + _receivers.length <= GS_SALE_MAX);
_reserveCounter += _receivers.length;
require(_reserveCounter <= GS_AIRDROP);
for (uint256 i = 0; i < _receivers.length; i++) {
internalMint(_receivers[i]);
}
}
function internalMint(address destination) internal {
_tokens[currentSupply] = _generateAttributeSet(currentSupply, destination);
_mint(destination, currentSupply);
currentSupply++;
}
function flipSaleState() external onlyOwner {
saleLive = !saleLive;
}
function flipPresaleState() external onlyOwner {
presaleLive = !presaleLive;
}
function setSignerAddress(address newSigner) external onlyOwner {
_signer = newSigner;
}
function withdraw() external onlyOwner {
payable(GS_TEAM).transfer(address(this).balance);
}
function totalSupply() public view returns (uint) {
return currentSupply;
}
function tokensOfOwner(address _owner, uint startId, uint endId) external view returns(uint256[] memory ) {
uint256 tokenCount = balanceOf(_owner);
if (tokenCount == 0) {
return new uint256[](0);
} else {
uint256[] memory result = new uint256[](tokenCount);
uint256 index = 0;
for (uint256 tokenId = startId; tokenId < endId; tokenId++) {
if (index == tokenCount) break;
if (ownerOf(tokenId) == _owner) {
result[index] = tokenId;
index++;
}
}
return result;
}
}
function _generateAttributeSet(uint256 _tokenId, address _sender) internal returns(uint256) {
_nonce++;
uint256 rndNumber = uint256(keccak256(abi.encodePacked(block.difficulty, block.timestamp, _tokenId, _sender, _nonce)));
uint256 hash = GoatLibrary.selectTraitSoup(rndNumber % 100);
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitBowl(rndNumber % 100) << 8;
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitFur(rndNumber % 100) << 16;
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitTeeth(rndNumber % 100) << 24;
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitHorns(rndNumber % 100) << 32;
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitHats(rndNumber % 100) << 40;
rndNumber >>= 12;
hash |= GoatLibrary.selectTraitEyes(rndNumber % 100) << 48;
return hash;
}
// credits to Anoynmice Mouse Dev for the inspiration of the SVG generation and compression algorithm
// which is an MIT licensed contract
function _generateSvg(uint256 _traitSet) internal view returns(string memory) {
string memory svg;
for(uint256 i = 0; i < 7; i++) {
uint256 idx = _traitSet & 0xff;
for(uint256 p = 0; p < _attributes[i][idx].pixelCount; p++) {
string memory data = GoatLibrary.substring(_attributes[i][idx].svgPath, p * 5, p * 5 + 5);
uint8 x = uint8(bytes(data)[0]) - 97;
uint8 y = uint8(bytes(data)[1]) - 97;
svg = string(abi.encodePacked(
svg,"<rect class='g",GoatLibrary.substring(data, 2, 5),"' x='", GoatLibrary.toString(x),"' y='",GoatLibrary.toString(y),"'/>"
)
);
}
_traitSet >>= 8;
}
svg = string(abi.encodePacked(
"<svg id='gs' xmlns='http://www.w3.org/2000/svg' preserveAspectRatio='xMinYMin meet' viewBox='0 0 24 24'>",
svg,
"<style>#gs{shape-rendering: crispedges;}rect{width:1px;height:1px;}.g100{fill:#000000}.g101{fill:#313131}.g102{fill:#252525}.g103{fill:#414040}.g104{fill:#4D4D4D}.g105{fill:#363636}.g106{fill:#003471}.g107{fill:#004A80}.g108{fill:#005E20}.g109{fill:#74A33E}.g110{fill:#6A9736}.g111{fill:#0054A6}.g112{fill:#598527}.g113{fill:#ABA000}.g114{fill:#CFBA5D}.g115{fill:#E8D782}.g116{fill:#E5D685}.g117{fill:#E0CE78}.g118{fill:#D7C264}.g119{fill:#C1AC50}.g120{fill:#DBC86D}.g121{fill:#D4BE5D}.g122{fill:#CCCCCC}.g123{fill:#FFFFFF}.g124{fill:#EBEBEB}.g125{fill:#C4393C}.g126{fill:#D14448}.g127{fill:#BC282C}.g128{fill:#B1191D}.g129{fill:#2C2422}.g130{fill:#6D6A6A}.g131{fill:#603913}.g132{fill:#593008}.g133{fill:#B5B5B5}.g134{fill:#563310}.g135{fill:#683F18}.g136{fill:#5C330B}.g137{fill:#5B3511}.g138{fill:#197B30}.g139{fill:#D7CC03}.g140{fill:#FFF200}.g141{fill:#8B3E0E}.g142{fill:#A34E19}.g143{fill:#D7640C}.g144{fill:#BD5717}.g145{fill:#2075A8}.g146{fill:#5F99BB}.g147{fill:#4D463E}.g148{fill:#F33C43}.g149{fill:#0E5024}.g150{fill:#5D981A}.g151{fill:#0C5D28}.g152{fill:#824E1C}.g153{fill:#C69C6D}.g154{fill:#362F2D}.g155{fill:#A67C52}.g156{fill:#F8F8F8}.g157{fill:#111111}.g158{fill:#636363}.g159{fill:#827C53}.g160{fill:#2F2D1E}.g161{fill:#00FFFF}.g162{fill:#27E5E5}.g163{fill:#2E3192}.g164{fill:#E60009}.g165{fill:#ED1C24}.g166{fill:#F6F6F6}.g167{fill:#08FFF4}.g168{fill:#00E4DA}.g169{fill:#6DCFF6}.g170{fill:#EFAE20}.g171{fill:#F8D00F}.g172{fill:#ECB223}.g173{fill:#F2B423}.g174{fill:#F7CE12}.g175{fill:#F7CF0D}.g176{fill:#F5BC13}.g177{fill:#F6CB0D}.g178{fill:#FBBA1E}.g179{fill:#F5CC10}.g180{fill:#F8D00E}.g181{fill:#F3BC1B}.g182{fill:#F6CD0F}.g183{fill:#FBBB1B}.g184{fill:#F9CD12}.g185{fill:#F6BA1B}.g186{fill:#F6C90E}.g187{fill:#EEAD1D}.g188{fill:#F7CB12}.g189{fill:#EBAC1F}.g190{fill:#ECAA16}.g191{fill:#F7C614}.g192{fill:#F0B31A}.g193{fill:#EDAE23}.g194{fill:#F2AD21}.g195{fill:#F3B71B}.g196{fill:#F3BF14}.g197{fill:#E4A12E}.g198{fill:#E5A124}.g199{fill:#EAA621}.g200{fill:#F4B51C}.g201{fill:#F5B619}.g202{fill:#F2B21C}.g203{fill:#F6B71C}.g204{fill:#FFFF00}.g205{fill:#03A600}.g206{fill:#A6001C}.g207{fill:#A1B92F}.g208{fill:#B2813E}.g209{fill:#BB9F4B}.g210{fill:#FCF8FF}.g211{fill:#5D8429}.g212{fill:#6E930F}.g213{fill:#E9EBB9}.g214{fill:#B59854}.g215{fill:#C4994B}.g216{fill:#69A22D}.g217{fill:#7EA21A}.g218{fill:#CAE4A7}.g219{fill:#779A18}.g220{fill:#B2CC09}.g221{fill:#C4EA32}.g222{fill:#7C9F0D}.g223{fill:#C1D224}.g224{fill:#A2CA1C}.g225{fill:#947235}.g226{fill:#906D29}.g227{fill:#6EA21A}.g228{fill:#EBF6D4}.g229{fill:#8AB510}.g230{fill:#8C692F}.g231{fill:#8B6A34}.g232{fill:#86B62E}.g233{fill:#8D9F3B}.g234{fill:#6FA11E}.g235{fill:#F6FBF4}.g236{fill:#FFFFFA}.g237{fill:#D7EFA1}.g238{fill:#F49AC1}.g239{fill:#F06EAA}.g240{fill:#FDBED9}.g241{fill:#F3438F}.g242{fill:#FBD1E3}.g243{fill:#B9006E}.g244{fill:#1A1A18}.g245{fill:#E01313}.g246{fill:#B7B7B7}.g247{fill:#C92121}.g248{fill:#FF0000}.g249{fill:#FF4747}.g250{fill:#6D3703}.g251{fill:#763B02}.g252{fill:#81450B}.g253{fill:#6D3907}.g254{fill:#99724A}.g255{fill:#894C11}.g256{fill:#8C6239}.g257{fill:#592D00}.g258{fill:#9B4E00}.g259{fill:#B47A40}.g260{fill:#261300}.g261{fill:#F9FB96}.g262{fill:#5674B9}.g263{fill:#7DA7D9}.g264{fill:#B5D3F6}.g265{fill:#F26522}.g266{fill:#D65A20}.g267{fill:#8A8A8A}.g268{fill:#8E8E8E}.g269{fill:#ACA49E}.g270{fill:#8560A8}.g271{fill:#F26C4F}.g272{fill:#007236}.g273{fill:#00A651}.g274{fill:#616161}.g275{fill:#BE8053}.g276{fill:#575656}.g277{fill:#A87046}.g278{fill:#302F2F}.g279{fill:#679CF1}.g280{fill:#3C81F0}.g281{fill:#26518F}.g282{fill:#CEB858}.g283{fill:#D6C162}.g284{fill:#EDE198}.g285{fill:#E9DC8E}.g286{fill:#E1D07B}.g287{fill:#D9C569}.g288{fill:#F3EBA7}.g289{fill:#F0E6A0}.g290{fill:#DDCA72}.g291{fill:#F5EEAC}.g292{fill:#BFBCBC}.g293{fill:#ACACAC}.g294{fill:#D7D7D7}.g295{fill:#7FFEA1}.g296{fill:#0FFF50}.g297{fill:#64FB8D}.g298{fill:#FD48AB}.g299{fill:#FF1494}.g300{fill:#980F5A}.g301{fill:#F1A367}.g302{fill:#F08B3C}.g303{fill:#8F5526}.g304{fill:#BB77E2}.g305{fill:#AA51DC}.g306{fill:#643283}.g307{fill:#8E11BF}.g308{fill:#B32DE8}.g309{fill:#F13655}.g310{fill:#BF1330}.g311{fill:#00BFF3}.g312{fill:#069AC3}.g313{fill:#B1462E}.g314{fill:#3CB878}.g315{fill:#0D9951}.g316{fill:#DCD331}.g317{fill:#BBD8A8}.g318{fill:#F26D7D}.g319{fill:#9E0B0F}.g320{fill:#9B5D2F}.g321{fill:#CD0C12}.g322{fill:#FCE695}.g323{fill:#C7945B}.g324{fill:#E9C364}.g325{fill:#F6ED5C}.g326{fill:#754C24}.g327{fill:#CDA0DE}.g328{fill:#E7BAF8}.g329{fill:#DDB2ED}.g330{fill:#AE7C4B}.g331{fill:#E1AEF5}.g332{fill:#CDA3DD}.g333{fill:#E3B5F5}.g334{fill:#E8BFF9}.g335{fill:#BE92D0}.g336{fill:#720F0F}.g337{fill:#1C84C8}.g338{fill:#FBFBFB}.g339{fill:#4DC0B8}.g340{fill:#F7941D}.g341{fill:#FECB4B}.g342{fill:#65D7CF}.g343{fill:#DCA825}.g344{fill:#5C5354}.g345{fill:#FFD8AD}.g346{fill:#C8C9CB}.g347{fill:#706C6D}.g348{fill:#38F152}.g349{fill:#636161}.g350{fill:#A7A7A7}.g351{fill:#AA7147}.g352{fill:#FF5900}.g353{fill:#7A0026}.g354{fill:#7A1010}.g355{fill:#7A2910}.g356{fill:#FF5300}.g357{fill:#E9D837}.g358{fill:#39B54A}.g359{fill:#FFF596}.g360{fill:#FDC689}.g361{fill:#685647}.g362{fill:#C79672}.g363{fill:#9EFAB6}.g364{fill:#4CFB7C}.g365{fill:#CB67FC}.g366{fill:#DA92FE}.g367{fill:#343434}.g368{fill:#BB33FF}.g369{fill:#F9F9F9}.g370{fill:#ACB8B7}.g371{fill:#E58A1D}.g372{fill:#B6714B}.g373{fill:#E0BF6C}.g374{fill:#A67DBD}.g375{fill:#7B2E00}.g376{fill:#A0410D}.g377{fill:#EDE10C}.g378{fill:#BD8CBF}.g379{fill:#2CF222}</style></svg>"
)
);
return svg;
}
// credits to Anoynmice Mouse Dev for the implementation of the trait set conversion to OpenSea metadata JSON format,
// which is an MIT licensed contract
function hashToMetadata(uint256 _traitSet) internal view returns (string memory) {
string memory metadataString;
for (uint8 i = 0; i < 7; i++) {
uint256 idx = _traitSet & 0xff;
metadataString = string(abi.encodePacked(metadataString,'{"trait_type":"',_attributes[i][idx].attr_type,'","value":"',_attributes[i][idx].name,'"}'));
if (i != 6)
metadataString = string(abi.encodePacked(metadataString, ","));
_traitSet >>= 8;
}
return string(abi.encodePacked("[", metadataString, "]"));
}
function tokenURI(uint256 _id) public view override returns (string memory) {
require(_exists(_id), "TOKEN_DOES_NOT_EXIST");
uint256 hash = _tokens[_id];
return
string(
abi.encodePacked(
"data:application/json;base64,",
GoatLibrary.encode(
bytes(
string(
abi.encodePacked(
'{"name": "Goat Soup #',
GoatLibrary.toString(_id),
'", "description": "Goat Soup genesis collection is a fully on chain NFT series of 3,744. All the metadata and images are generated and stored 100% on-chain.", "image": "data:image/svg+xml;base64,',
GoatLibrary.encode(
bytes(_generateSvg(hash))
),
'","attributes":',
hashToMetadata(hash),
"}"
)
)
)
)
)
);
}
function clearAttributes() external onlyOwner {
for(uint8 i = 0; i < 7; i++) {
delete _attributes[i];
}
}
function addAttributes(uint _attributeIndex, Attribute[] memory attributes) external onlyOwner {
for(uint8 i = 0; i < attributes.length; i++) {
_attributes[_attributeIndex].push(
Attribute(
attributes[i].name,
attributes[i].attr_type,
attributes[i].svgPath,
attributes[i].pixelCount
)
);
}
}
}
<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
library GoatLibrary {
// Provides a function for encoding some bytes in base64
// By Brecht Devos <[email protected]>
string internal constant TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
function encode(bytes memory data) internal pure returns (string memory) {
if (data.length == 0) return "";
// load the table into memory
string memory table = TABLE;
// multiply by 4/3 rounded up
uint256 encodedLen = 4 * ((data.length + 2) / 3);
// add some extra buffer at the end required for the writing
string memory result = new string(encodedLen + 32);
assembly {
// set the actual output length
mstore(result, encodedLen)
// prepare the lookup table
let tablePtr := add(table, 1)
// input ptr
let dataPtr := data
let endPtr := add(dataPtr, mload(data))
// result ptr, jump over length
let resultPtr := add(result, 32)
// run over the input, 3 bytes at a time
for {
} lt(dataPtr, endPtr) {
} {
dataPtr := add(dataPtr, 3)
// read 3 bytes
let input := mload(dataPtr)
// write 4 characters
mstore(
resultPtr,
shl(248, mload(add(tablePtr, and(shr(18, input), 0x3F))))
)
resultPtr := add(resultPtr, 1)
mstore(
resultPtr,
shl(248, mload(add(tablePtr, and(shr(12, input), 0x3F))))
)
resultPtr := add(resultPtr, 1)
mstore(
resultPtr,
shl(248, mload(add(tablePtr, and(shr(6, input), 0x3F))))
)
resultPtr := add(resultPtr, 1)
mstore(
resultPtr,
shl(248, mload(add(tablePtr, and(input, 0x3F))))
)
resultPtr := add(resultPtr, 1)
}
// padding with '='
switch mod(mload(data), 3)
case 1 {
mstore(sub(resultPtr, 2), shl(240, 0x3d3d))
}
case 2 {
mstore(sub(resultPtr, 1), shl(248, 0x3d))
}
}
return result;
}
function parseInt(string memory _a) internal pure returns (uint8 _parsedInt) {
bytes memory bresult = bytes(_a);
uint8 minty = 0;
for (uint8 i = 0; i < bresult.length; i++) {
if (
(uint8(uint8(bresult[i])) >= 48) &&
(uint8(uint8(bresult[i])) <= 57)
) {
minty *= 10;
minty += uint8(bresult[i]) - 48;
}
}
return minty;
}
function substring(string memory str, uint startIndex, uint endIndex) internal pure returns (string memory) {
bytes memory strBytes = bytes(str);
bytes memory result = new bytes(endIndex-startIndex);
for(uint i = startIndex; i < endIndex; i++) {
result[i-startIndex] = strBytes[i];
}
return string(result);
}
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 selectTraitSoup(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 2) { return 0; }
if(_rnd < 6) { return 1; }
if(_rnd < 11) { return 2; }
if(_rnd < 18) { return 3; }
if(_rnd < 26) { return 4; }
if(_rnd < 34) { return 5; }
if(_rnd < 42) { return 6; }
if(_rnd < 52) { return 7; }
if(_rnd < 65) { return 8; }
if(_rnd < 80) { return 9; }
return 10;
}
function selectTraitBowl(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 2) { return 0; }
if(_rnd < 6) { return 1; }
if(_rnd < 11) { return 2; }
if(_rnd < 18) { return 3; }
if(_rnd < 25) { return 4; }
if(_rnd < 33) { return 5; }
if(_rnd < 42) { return 6; }
if(_rnd < 52) { return 7; }
if(_rnd < 64) { return 8; }
return 9;
}
function selectTraitFur(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 2) { return 0; }
if(_rnd < 5) { return 1; }
if(_rnd < 9) { return 2; }
if(_rnd < 14) { return 3; }
if(_rnd < 24) { return 4; }
if(_rnd < 34) { return 5; }
if(_rnd < 50) { return 6; }
if(_rnd < 70) { return 7; }
return 8;
}
function selectTraitTeeth(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 2) { return 0; }
if(_rnd < 7) { return 1; }
if(_rnd < 17) { return 2; }
if(_rnd < 35) { return 3; }
if(_rnd < 60) { return 4; }
return 5;
}
function selectTraitHorns(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 5) { return 0; }
if(_rnd < 15) { return 1; }
if(_rnd < 50) { return 2; }
return 3;
}
function selectTraitHats(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 1) { return 0; }
if(_rnd < 3) { return 1; }
if(_rnd < 6) { return 2; }
if(_rnd < 9) { return 3; }
if(_rnd < 15) { return 4; }
if(_rnd < 22) { return 5; }
if(_rnd < 29) { return 6; }
if(_rnd < 38) { return 7; }
if(_rnd < 48) { return 8; }
if(_rnd < 59) { return 9; }
return 10;
}
function selectTraitEyes(uint256 _rnd) internal pure returns(uint256) {
if(_rnd < 1) { return 0; }
if(_rnd < 3) { return 1; }
if(_rnd < 6) { return 2; }
if(_rnd < 11) { return 3; }
if(_rnd < 19) { return 4; }
if(_rnd < 31) { return 5; }
if(_rnd < 49) { return 6; }
if(_rnd < 72) { return 7; }
return 8;
}
}
<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../Strings.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} else if (error == RecoverError.InvalidSignatureV) {
revert("ECDSA: invalid signature 'v' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
// Check the signature length
// - case 65: r,s,v signature (standard)
// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else if (signature.length == 64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
vs := mload(add(signature, 0x40))
}
return tryRecover(hash, r, vs);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address, RecoverError) {
bytes32 s;
uint8 v;
assembly {
s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
v := add(shr(255, vs), 27)
}
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
if (v != 27 && v != 28) {
return (address(0), RecoverError.InvalidSignatureV);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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);
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC721/extensions/ERC721Enumerable.sol)
pragma solidity ^0.8.0;
import "../ERC721.sol";
import "./IERC721Enumerable.sol";
/**
* @dev This implements an optional extension of {ERC721} defined in the EIP that adds
* enumerability of all the token ids in the contract as well as all token ids owned by each
* account.
*/
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
// Mapping from owner to list of owned token IDs
mapping(address => mapping(uint256 => uint256)) private _ownedTokens;
// Mapping from token ID to index of the owner tokens list
mapping(uint256 => uint256) private _ownedTokensIndex;
// Array with all token ids, used for enumeration
uint256[] private _allTokens;
// Mapping from token id to position in the allTokens array
mapping(uint256 => uint256) private _allTokensIndex;
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
return _ownedTokens[owner][index];
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _allTokens.length;
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/
function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
return _allTokens[index];
}
/**
* @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` cannot be the zero address.
* - `to` cannot be the zero address.
*
* 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 override {
super._beforeTokenTransfer(from, to, tokenId);
if (from == address(0)) {
_addTokenToAllTokensEnumeration(tokenId);
} else if (from != to) {
_removeTokenFromOwnerEnumeration(from, tokenId);
}
if (to == address(0)) {
_removeTokenFromAllTokensEnumeration(tokenId);
} else if (to != from) {
_addTokenToOwnerEnumeration(to, tokenId);
}
}
/**
* @dev Private function to add a token to this extension's ownership-tracking data structures.
* @param to address representing the new owner of the given token ID
* @param tokenId uint256 ID of the token to be added to the tokens list of the given address
*/
function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
uint256 length = ERC721.balanceOf(to);
_ownedTokens[to][length] = tokenId;
_ownedTokensIndex[tokenId] = length;
}
/**
* @dev Private function to add a token to this extension's token tracking data structures.
* @param tokenId uint256 ID of the token to be added to the tokens list
*/
function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
_allTokensIndex[tokenId] = _allTokens.length;
_allTokens.push(tokenId);
}
/**
* @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
* while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
* gas optimizations e.g. when performing a transfer operation (avoiding double writes).
* This has O(1) time complexity, but alters the order of the _ownedTokens array.
* @param from address representing the previous owner of the given token ID
* @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/
function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
// To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
uint256 tokenIndex = _ownedTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary
if (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
_ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
}
// This also deletes the contents at the last position of the array
delete _ownedTokensIndex[tokenId];
delete _ownedTokens[from][lastTokenIndex];
}
/**
* @dev Private function to remove a token from this extension's token tracking data structures.
* This has O(1) time complexity, but alters the order of the _allTokens array.
* @param tokenId uint256 ID of the token to be removed from the tokens list
*/
function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
// To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = _allTokens.length - 1;
uint256 tokenIndex = _allTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
// rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
// an 'if' statement (like in _removeTokenFromOwnerEnumeration)
uint256 lastTokenId = _allTokens[lastTokenIndex];
_allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
// This also deletes the contents at the last position of the array
delete _allTokensIndex[tokenId];
_allTokens.pop();
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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 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 {}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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);
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC721/extensions/IERC721Enumerable.sol)
pragma solidity ^0.8.0;
import "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Enumerable is IERC721 {
/**
* @dev Returns the total amount of tokens stored by the contract.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns a token ID owned by `owner` at a given `index` of its token list.
* Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);
/**
* @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
* Use along with {totalSupply} to enumerate all tokens.
*/
function tokenByIndex(uint256 index) external view returns (uint256);
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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;
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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;
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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);
}
}
}
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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);
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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 `IERC721.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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`, 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;
}
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// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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);
}