Contract Source Code:
// SPDX-License-Identifier: MIT
//
/*
*
* || .-:'"-._
* | | _(, )
* | | ,'O"( )>
* | | `-.-( )
* || `-._._.-'
* // //
*
* ASTERIA LABS:
* @Danny_One_
*
*/
import "./ERC721_efficient.sol";
pragma solidity ^0.8.0;
interface ILambDuh {
function balanceOf(address sender) external view returns (uint256);
}
contract LambDuhsPX is ERC721Enumerable, Ownable, nonReentrant {
uint256 public pxPS_Price = 50000000000000000; // 0.050 ETH
uint256 public pxLambPrice = 55000000000000000; // 0.055 ETH
uint256 public constant maxPxLambPurchase = 10;
uint256 public immutable MAX_PXLAMB = 8500; // 8.5k supply
uint256 public immutable MAX_PRESALE = 6150; // total presale lambs allowed
//Reserve PX Lamb for team - Giveaways/Prizes etc
uint256 public immutable MAX_PXLAMBRESERVE = 100; // total team reserves allowed
uint256 public immutable MAX_PXPORTALS = 1500; // total portal lambs allowed
uint256 public immutable MAX_FREECLAIM = 20; // total free lambs allowed
address public tokenDeposit = 0x2a6f3F959eb2cb0982B2dB5D4Cb2aEFb8B3cd4a3; // address to receive custom ERC20
string public PXprovenance;
uint256 public maxSaleMint = 10;
uint256 public teamMints = 0;
enum SaleState {
Paused,
Presale,
Phase2,
Open
}
SaleState public saleState;
bytes32 public MerkleRoot =
0x88e10a1c8b916fcfde160f7ab84e06107f52e258421fc3bf0b7f4d3a3e22c0b1;
ILambDuh public LambContract =
ILambDuh(0x1F0f72e6Dc2EA6FDe3A32A1B3fD47A26a3293Dc9);
struct TPToken {
uint64 MAX_TOKEN;
uint64 tokenSupply;
uint128 Cost;
IERC20 Contract;
}
enum TokenName {
BAMBOO,
PIXL,
ROOLAH,
SEED,
STAR,
LAMEX,
SPIT,
ETH
}
mapping(TokenName => TPToken) public mintableTokens;
address public proxyRegistryAddress;
struct AddressInfo {
uint64 ownerFreeClaims;
uint64 ownerPresaleMints;
bool[7] tokenMinted;
bool projectProxy;
}
mapping(address => AddressInfo) public addressInfo;
uint16[] public portalsIDs;
constructor() ERC721("Lamb Duhs PX", "LDPX") {}
// PUBLIC FUNCTIONS
function mint(uint256 _mintAmount) public payable reentryLock {
require(saleState > SaleState.Phase2, "public sale is not active");
require(msg.sender == tx.origin, "no proxy transactions");
uint256 supply = totalSupply();
require(_mintAmount < maxSaleMint + 1, "max transaction exceeded");
require(supply + _mintAmount < MAX_PXLAMB + 1, "max supply exceeded");
require(msg.value >= _mintAmount * pxLambPrice, "not enough ETH sent");
for (uint256 i = 0; i < _mintAmount; i++) {
_safeMint(msg.sender, supply + i);
}
}
function mintPresale(
bytes32[] memory _proof,
bytes2 _maxAmountKey,
uint256 _mintAmount,
TokenName _tokenName
) public payable reentryLock {
require(
MerkleRoot > 0x00 && saleState > SaleState.Paused,
"presale period not open!"
);
uint256 supply = totalSupply();
require(supply + _mintAmount < MAX_PXLAMB + 1, "max supply exceeded");
require(
MerkleProof.verify(
_proof,
MerkleRoot,
keccak256(abi.encodePacked(msg.sender, _maxAmountKey))
),
"invalid proof-key combo"
);
uint8 allowed = uint8(uint16(_maxAmountKey));
if (_tokenName == TokenName.ETH) {
require(saleState < SaleState.Open, "presale closed!");
require(
msg.value >= _mintAmount * pxPS_Price,
"not enough ETH sent"
);
require(
mintableTokens[_tokenName].tokenSupply + _mintAmount <
MAX_PRESALE + 1,
"presale sold out"
);
if (saleState == SaleState.Presale) {
require(
addressInfo[msg.sender].ownerPresaleMints + _mintAmount <
allowed + 1,
"max presale claims exceeded"
);
} else if (saleState == SaleState.Phase2) {
require(
addressInfo[msg.sender].ownerPresaleMints + _mintAmount <
2 * allowed + 1,
"max phase 2 claims exceeded"
);
}
mintableTokens[_tokenName].tokenSupply += uint64(_mintAmount);
addressInfo[msg.sender].ownerPresaleMints += uint64(_mintAmount);
} else {
// LAMEX, SPIT
require(_tokenName > TokenName.STAR, "invalid token");
require(_mintAmount < 2, "only 1 allowed");
require(
addressInfo[msg.sender].tokenMinted[uint256(_tokenName)] ==
false,
"tokenMint already claimed"
);
require(
mintableTokens[_tokenName].tokenSupply <
mintableTokens[_tokenName].MAX_TOKEN,
"max tokenMint exceeded"
);
mintableTokens[_tokenName].tokenSupply += uint64(_mintAmount);
addressInfo[msg.sender].tokenMinted[uint256(_tokenName)] = true;
}
for (uint256 i = 0; i < uint256(_mintAmount); i++) {
_safeMint(msg.sender, supply + i);
}
}
// TokenName: BAMBOO, PIXL, ROOLAH, SEED, STAR
function mintWithToken(TokenName _tokenName) public reentryLock {
require(
MerkleRoot > 0x00 && saleState > SaleState.Paused,
"token mint not open!"
);
uint256 supply = totalSupply();
require(supply < MAX_PXLAMB, "max supply exceeded");
require(
mintableTokens[_tokenName].tokenSupply <
mintableTokens[_tokenName].MAX_TOKEN,
"max tokenMint exceeded"
);
require(
addressInfo[msg.sender].tokenMinted[uint256(_tokenName)] == false,
"tokenMint already claimed"
);
require(_tokenName < TokenName.LAMEX, "invalid ERC20");
bool success = mintableTokens[_tokenName].Contract.transferFrom(
msg.sender,
tokenDeposit,
mintableTokens[_tokenName].Cost
);
require(success, "token transfer failed");
mintableTokens[_tokenName].tokenSupply += 1;
addressInfo[msg.sender].tokenMinted[uint256(_tokenName)] = true;
_safeMint(msg.sender, supply);
}
function mintFreeClaim(
bytes32[] memory _proof,
bytes2 _maxAmountKey,
uint256 _mintAmount
) public reentryLock {
require(
MerkleRoot > 0x00 && saleState > SaleState.Paused,
"free claim period not open!"
);
uint256 supply = totalSupply();
require(supply + _mintAmount < MAX_PXLAMB + 1, "max supply exceeded");
uint256 portalSupply = supply - portalsIDs.length;
require(
portalSupply + _mintAmount < MAX_PXPORTALS + 1,
"max portals exceeded"
);
require(
MerkleProof.verify(
_proof,
MerkleRoot,
keccak256(abi.encodePacked(msg.sender, _maxAmountKey))
),
"invalid proof-key combo"
);
uint8 allowed = uint8(bytes1(_maxAmountKey));
require(
addressInfo[msg.sender].ownerFreeClaims + _mintAmount < allowed + 1,
"max allowed claims exceeded"
);
require(
addressInfo[msg.sender].ownerFreeClaims + _mintAmount <
MAX_FREECLAIM + 1,
"max free claims exceeded"
);
require(
LambContract.balanceOf(msg.sender) >=
3 * (_mintAmount + addressInfo[msg.sender].ownerFreeClaims),
"insuffient OG Lamb balance"
);
addressInfo[msg.sender].ownerFreeClaims += uint64(_mintAmount);
portalSupply += uint64(_mintAmount);
for (uint256 i = 0; i < uint256(_mintAmount); i++) {
portalsIDs.push(uint16(supply + i));
_safeMint(msg.sender, supply + i);
}
}
function checkProofWithKey(bytes32[] memory proof, bytes memory key)
public
view
returns (bool)
{
return
MerkleProof.verify(
proof,
MerkleRoot,
keccak256(abi.encodePacked(msg.sender, key))
);
}
function isApprovedForAll(address _owner, address operator)
public
view
override(ERC721, IERC721)
returns (bool)
{
MarketplaceProxyRegistry proxyRegistry = MarketplaceProxyRegistry(
proxyRegistryAddress
);
if (
address(proxyRegistry.proxies(_owner)) == operator ||
addressInfo[operator].projectProxy
) return true;
return super.isApprovedForAll(_owner, operator);
}
function getTokensMinted(address _sender)
public
view
returns (bool[7] memory)
{
return addressInfo[_sender].tokenMinted;
}
function getPortalsIDs() public view returns (uint16[] memory) {
return portalsIDs;
}
// ONLY OWNER FUNCTIONS
function setBaseURI(string memory baseURI_) public onlyOwner {
_setBaseURI(baseURI_);
}
function setMerkleRoot(bytes32 _MerkleRoot) public onlyOwner {
MerkleRoot = _MerkleRoot;
}
function setSaleState(SaleState _state) public onlyOwner {
saleState = _state;
}
function setProxyRegistry(address _proxyRegistryAddress) public onlyOwner {
proxyRegistryAddress = _proxyRegistryAddress;
}
function withdraw() public onlyOwner {
uint256 balance = address(this).balance;
(bool success, ) = address(0x6e37d65D20Ec3842358fb326A03E5E0ca47A0fa5)
.call{value: balance}("");
require(success, "Transfer failed.");
}
function setPrice(uint256 _newPrice, uint256 _newPSPrice) public onlyOwner {
pxLambPrice = _newPrice;
pxPS_Price = _newPSPrice;
}
function setTokenConfig(
TokenName _token,
uint64 _MAX_TOKEN,
uint128 _Cost,
address _tokenAddress
) public onlyOwner {
if (mintableTokens[_token].tokenSupply > 0) {
require(
mintableTokens[_token].tokenSupply >= _MAX_TOKEN,
"supply already greater than max"
);
}
mintableTokens[_token].MAX_TOKEN = _MAX_TOKEN;
mintableTokens[_token].Cost = _Cost;
mintableTokens[_token].Contract = IERC20(_tokenAddress);
}
function setLambContract(address _lambOG) external onlyOwner {
if (address(LambContract) != _lambOG) {
LambContract = ILambDuh(_lambOG);
}
}
function setTokenDeposit(address _tokenDeposit) public onlyOwner {
tokenDeposit = _tokenDeposit;
}
function setProvenance(string memory _provenance) public onlyOwner {
PXprovenance = _provenance;
}
// reserve function for team mints (giveaways & payments)
function teamMint(address _to, uint256 _reserveAmount) public onlyOwner {
require(
_reserveAmount + teamMints < MAX_PXLAMBRESERVE + 1,
"Not enough reserve left for team"
);
uint256 supply = totalSupply();
teamMints = teamMints + _reserveAmount;
for (uint256 i = 0; i < _reserveAmount; i++) {
_safeMint(_to, supply + i);
}
}
}
contract OwnableDelegateProxy {}
contract MarketplaceProxyRegistry {
mapping(address => OwnableDelegateProxy) public proxies;
}
/**
* Flattened contract dependencies for ERC721 NFT projects
* @Danny_One
*
*
* Added Merkle Proof presale list
* Improved Enumerable per new best practices to save gas
*
* Flattened from:
* MerkleProof.sol - Nuclear Nerds (2022-01-16)
* ERC721Enumerable.sol - Nuclear Nerds (2022-01-04)
* IERC721Enumerable.sol - Open Zeppelin (2022-01-04)
* OpenZeppelin (on 2021-11-18):
* IERC20.sol (2022-04-13)
* ERC721.sol **significantly modified
* IERC721.sol
* IERC721Receiver.sol
* IERC721Metadata.sol
* Address.sol
* Context.sol
* Ownable.sol
* Strings.sol
* Counters.sol
* ERC165.sol
* IERC165.sol
* nonReentrant (custom)
*
**/
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/MerkleProof.sol)
pragma solidity ^0.8.0;
/**
* @dev These functions deal with verification of Merkle Trees proofs.
*
* The proofs can be generated using the JavaScript library
* https://github.com/miguelmota/merkletreejs[merkletreejs].
* Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
*
* See `test/utils/cryptography/MerkleProof.test.js` for some examples.
*/
library MerkleProof {
/**
* @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
* defined by `root`. For this, a `proof` must be provided, containing
* sibling hashes on the branch from the leaf to the root of the tree. Each
* pair of leaves and each pair of pre-images are assumed to be sorted.
*/
function verify(
bytes32[] memory proof,
bytes32 root,
bytes32 leaf
) internal pure returns (bool) {
return processProof(proof, leaf) == root;
}
/**
* @dev Returns the rebuilt hash obtained by traversing a Merklee tree up
* from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
* hash matches the root of the tree. When processing the proof, the pairs
* of leafs & pre-images are assumed to be sorted.
*
* _Available since v4.4._
*/
function processProof(bytes32[] memory proof, bytes32 leaf)
internal
pure
returns (bytes32)
{
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
bytes32 proofElement = proof[i];
if (computedHash <= proofElement) {
// Hash(current computed hash + current element of the proof)
computedHash = _efficientHash(computedHash, proofElement);
} else {
// Hash(current element of the proof + current computed hash)
computedHash = _efficientHash(proofElement, computedHash);
}
}
return computedHash;
}
function _efficientHash(bytes32 a, bytes32 b)
private
pure
returns (bytes32 value)
{
assembly {
mstore(0x00, a)
mstore(0x20, b)
value := keccak256(0x00, 0x40)
}
}
}
// OpenZeppelin Contracts v4.3.2 (utils/introspection/IERC165.sol)
/**
* @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);
}
// OpenZeppelin Contracts v4.3.2 (utils/introspection/ERC165.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;
}
}
// OpenZeppelin Contracts v4.3.2 (utils/Strings.sol)
/**
* @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);
}
}
// OpenZeppelin Contracts v4.3.2 (utils/Context.sol)
/**
* @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;
}
}
// OpenZeppelin Contracts v4.3.2 (access/Ownable.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);
}
}
// OpenZeppelin Contracts v4.3.2 (utils/Address.sol)
/**
* @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);
}
}
}
}
// OpenZeppelin Contracts v4.3.2 (token/ERC721/IERC721.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;
}
// OpenZeppelin Contracts v4.3.2 (token/ERC721/extensions/IERC721Metadata.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);
}
// OpenZeppelin Contracts v4.3.2 (token/ERC721/IERC721Receiver.sol)
/**
* @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);
}
// OpenZeppelin Contracts v4.3.2 (utils/Counters.sol)
/**
* @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;
}
}
/**
* @title nonReentrant module to prevent recursive calling of functions
* @dev See https://medium.com/coinmonks/protect-your-solidity-smart-contracts-from-reentrancy-attacks-9972c3af7c21
* part of a flattened ERC721 dependency collection compiled by Danny_One
*/
abstract contract nonReentrant {
bool private _reentryKey = false;
modifier reentryLock() {
require(!_reentryKey, "cannot reenter a locked function");
_reentryKey = true;
_;
_reentryKey = false;
}
}
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender)
external
view
returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 amount
) external returns (bool);
}
// OpenZeppelin Contracts v4.3.2 (token/ERC721/ERC721.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}.
*
* Modified from original OpenZeppelin version to improve gas performance
*
*/
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;
// Base URI
string private _baseURI;
// Owner array
address[] internal _owners;
// 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}.
* updated for owner array
*/
function balanceOf(address owner)
public
view
virtual
override
returns (uint256)
{
require(
owner != address(0),
"ERC721: balance query for the zero address"
);
uint256 _ownerBalance = 0;
for (uint256 i = 0; i < _owners.length; i++) {
if (_owners[i] == owner) _ownerBalance++;
}
return _ownerBalance;
}
/**
* @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 _baseURI;
}
/**
* @dev Internal function to set the base URI for all token IDs. It is
* automatically added as a prefix to the value returned in {tokenURI},
* or to the token ID if {tokenURI} is empty.
*/
function _setBaseURI(string memory baseURI_) internal virtual {
_baseURI = baseURI_;
}
/**
* @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 tokenId < _owners.length && _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);
_owners.push(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);
_owners[tokenId] = address(0);
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);
_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 {}
}
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Enumerable.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);
}
/**
* borrowed from Nuclear Nerds implementation
* @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 but rips out the core of the gas-wasting processing that comes from OpenZeppelin.
*/
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
/**
* @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-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _owners.length;
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/
function tokenByIndex(uint256 index)
public
view
virtual
override
returns (uint256)
{
require(
index < _owners.length,
"ERC721Enumerable: global index out of bounds"
);
return index;
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/
function tokenOfOwnerByIndex(address owner, uint256 index)
public
view
virtual
override
returns (uint256 tokenId)
{
require(
index < balanceOf(owner),
"ERC721Enumerable: owner index out of bounds"
);
uint256 count;
for (uint256 i; i < _owners.length; i++) {
if (owner == _owners[i]) {
if (count == index) return i;
else count++;
}
}
revert("ERC721Enumerable: owner index out of bounds");
}
}