Contract Source Code:

//SPDX-License-Identifier: UNLICENSED AND MIT

pragma solidity ^0.8.0;


/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}

// OpenZeppelin Contracts (last updated v5.0.0) (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 (last updated v5.0.0) (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);
 * }
 * ```
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

abstract contract Ownable {
    event OwnershipTransferred(address indexed user, address indexed newOwner);

    error Unauthorized();
    error InvalidOwner();

    address public owner;

    modifier onlyOwner() virtual {
        if (msg.sender != owner) revert Unauthorized();

        _;
    }

    constructor(address _owner) {
        if (_owner == address(0)) revert InvalidOwner();

        owner = _owner;

        emit OwnershipTransferred(address(0), _owner);
    }

    function transferOwnership(address _owner) public virtual onlyOwner {
        if (_owner == address(0)) revert InvalidOwner();

        owner = _owner;

        emit OwnershipTransferred(msg.sender, _owner);
    }

    function revokeOwnership() public virtual onlyOwner {
        owner = address(0);

        emit OwnershipTransferred(msg.sender, address(0));
    }
}



// "Fantom is Really Cool"
abstract contract STONER is Ownable {
    // Events
    event ERC20Transfer(
        address indexed from,
        address indexed to,
        uint256 amount
    );

    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 amount
    );

    event Transfer(
        address indexed from,
        address indexed to,
        uint256 indexed id
    );

    event ERC721Approval(
        address indexed owner,
        address indexed spender,
        uint256 indexed id
    );

    event ApprovalForAll(
        address indexed owner,
        address indexed operator,
        bool approved
    );

    // Errors
    error NotFound();
    error AlreadyExists();
    error InvalidRecipient();
    error InvalidSender();
    error UnsafeRecipient();

    // Metadata
    /// @dev Token name
    string public name;

    /// @dev Token symbol
    string public symbol;

    /// @dev Decimals for fractional representation
    uint8 public immutable decimals;

    /// @dev Total supply in fractionalized representation
    uint256 public immutable totalSupply;

    /// @dev Total supply in NFT representation
    uint256 public immutable totalNativeSupply;

    /// @dev Current mint counter, monotonically increasing to ensure accurate ownership
    uint256 public minted;

    // Mappings
    /// @dev Balance of user in fractional representation
    mapping(address => uint256) public balanceOf;

    /// @dev Allowance of user in fractional representation
    mapping(address => mapping(address => uint256)) public allowance;

    /// @dev Approval in native representaion
    mapping(uint256 => address) public getApproved;

    /// @dev Approval for all in native representation
    mapping(address => mapping(address => bool)) public isApprovedForAll;

    /// @dev Owner of id in native representation
    mapping(uint256 => address) internal _ownerOf;

    /// @dev Array of owned ids in native representation
    mapping(address => uint256[]) internal _owned;
    mapping(address => uint256[]) internal _contractOwned;

    /// @dev Tracks indices for the _owned mapping
    mapping(uint256 => uint256) internal _ownedIndex;

    /// @dev Addresses whitelisted from minting / burning for gas savings (pairs, routers, etc)
    mapping(address => bool) public whitelist;

    /// @dev Holds the IDs of NFTs that have been burned so that they can be re-used
    uint256[] public availableIds;

    // Constructor
    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals,
        uint256 _totalNativeSupply,
        address _owner
    ) Ownable(_owner) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        totalNativeSupply = _totalNativeSupply;
        totalSupply = _totalNativeSupply * (10**decimals);
    }

    /// @notice Initialization function to set pairs / etc
    ///         saving gas by avoiding mint / burn on unnecessary targets
    function setWhitelist(address target, bool state) public onlyOwner {
        whitelist[target] = state;
    }

    /// @notice Function to find owner of a given native token
    function ownerOf(uint256 id) public view virtual returns (address owner) {
        owner = _ownerOf[id];

        if (owner == address(0)) {
            revert NotFound();
        }
    }

    function totalAvailableIds() public view returns (uint256) {
        return availableIds.length;
    }

    function totalNFTsOwned(address owner) public view returns (uint256) {
        return _owned[owner].length;
    }

    /// @notice tokenURI must be implemented by child contract
    function tokenURI(uint256 id) public view virtual returns (string memory);

    /// @notice Function for token approvals
    /// @dev This function assumes id / native if amount less than or equal to current max id
    function approve(address spender, uint256 amountOrId)
        public
        virtual
        returns (bool)
    {
        if (amountOrId <= minted && amountOrId > 0) {
            address owner = _ownerOf[amountOrId];

            if (msg.sender != owner && !isApprovedForAll[owner][msg.sender]) {
                revert Unauthorized();
            }

            getApproved[amountOrId] = spender;

            emit Approval(owner, spender, amountOrId);
        } else {
            allowance[msg.sender][spender] = amountOrId;

            emit Approval(msg.sender, spender, amountOrId);
        }

        return true;
    }

    /// @notice Function native approvals
    function setApprovalForAll(address operator, bool approved) public virtual {
        isApprovedForAll[msg.sender][operator] = approved;

        emit ApprovalForAll(msg.sender, operator, approved);
    }

    /// @notice Function for mixed transfers
    /// @dev This function assumes id / native if amount less than or equal to current max id
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public returns (bool) {
        uint256 allowed = allowance[from][msg.sender];

        require(allowed >= amount, "Not enough allowance.");

        if (allowed != type(uint256).max)
            allowance[from][msg.sender] = allowed - amount;

        _transfer(from, to, amount);
        return true;
    }

    /// @notice Function for fractional transfers
    function transfer(address to, uint256 amount)
        public
        virtual
        returns (bool)
    {
        return _transfer(msg.sender, to, amount);
    }

    /// @notice Function for native transfers with contract support
    function safeTransferFrom(
        address from,
        address to,
        uint256 id
    ) public virtual {
        _nftTransferFrom(msg.sender, from, to, id);

        if (
            to.code.length != 0 &&
            ERC721Receiver(to).onERC721Received(msg.sender, from, id, "") !=
            ERC721Receiver.onERC721Received.selector
        ) {
            revert UnsafeRecipient();
        }
    }

    /// @notice Function for native transfers with contract support and callback data
    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        bytes calldata data
    ) public virtual {
        _nftTransferFrom(msg.sender, from, to, id);

        if (
            to.code.length != 0 &&
            ERC721Receiver(to).onERC721Received(msg.sender, from, id, data) !=
            ERC721Receiver.onERC721Received.selector
        ) {
            revert UnsafeRecipient();
        }
    }

    // testing only: delete before deploy
    function contractTokenBalance(address _contract)
        public
        view
        returns (uint256)
    {
        return
            balanceOf[_contract] -
            (_contractOwned[_contract].length * _getUnit());
    }

    function contractNFTBalance(address _contract)
        public
        view
        returns (uint256)
    {
        return _contractOwned[_contract].length;
    }

    function enoughTokenBalance(address _contract, uint256 amount)
        public
        view
        returns (bool)
    {
        uint256 tokenBalance = balanceOf[_contract] -
            (_contractOwned[_contract].length * _getUnit());
        return tokenBalance >= amount;
    }

    /// @notice Internal function for fractional transfers
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal returns (bool) {
        _beforeTokenTransfer(from, to, amount);

        uint256 unit = _getUnit();
        uint256 balanceBeforeSender = balanceOf[from];
        uint256 balanceBeforeReceiver = balanceOf[to];

        if (_isContract(from)) {
            uint256 tokenBalance = balanceBeforeSender -
                (_contractOwned[from].length * unit);
            require(tokenBalance >= amount, "Not enough token balance.");
        }

        balanceOf[from] -= amount;
        unchecked {
            balanceOf[to] += amount;
        }

        // Skip burn for certain addresses to save gas
        // Skip minting to smart contracts
        if (!_shouldSkip(from) || _owned[from].length > 0) {
            uint256 nftsToBurn = (balanceBeforeSender / unit) -
                (balanceOf[from] / unit);
            for (uint256 i = 0; i < nftsToBurn; i++) {
                _burnNFT(from);
            }
        }

        // Skip minting for certain addresses to save gas
        // Skip burning from smart contracts
        if (!_shouldSkip(to)) {
            uint256 nftsToMint = (balanceOf[to] / unit) -
                (balanceBeforeReceiver / unit);
            for (uint256 i = 0; i < nftsToMint; i++) {
                _mintNFT(to);
            }
        }

        emit ERC20Transfer(from, to, amount);
        return true;
    }

    function _mint(address recipient, uint256 quantity) internal {
        balanceOf[recipient] += quantity * _getUnit();

        for (uint256 index = 0; index < quantity; index++) {
            _mintNFT(recipient);
        }
    }

    function _nftTransferFrom(
        address msgSender,
        address from,
        address to,
        uint256 id
    ) internal {
        require(from == _ownerOf[id], "Sender is not owner of NFT.");
        require(to != address(0), "Cannot send to null address.");
        require(
            msgSender == from ||
                isApprovedForAll[from][msgSender] ||
                msgSender == getApproved[id],
            "Operator is not approved."
        );

        balanceOf[from] -= _getUnit();
        unchecked {
            balanceOf[to] += _getUnit();
        }

        _removeSpecificNFT(from, id);
        _deliverNFT(to, id);

        emit Transfer(from, to, id);
        emit ERC20Transfer(from, to, _getUnit());
    }

    // Internal utility logic
    function _getUnit() internal view returns (uint256) {
        return 10**decimals;
    }

    function _mintNFT(address to) internal virtual {
        if (to == address(0)) {
            revert InvalidRecipient();
        }

        uint256 id;

        if (availableIds.length == 0) {
            unchecked {
                minted++;
            }
            require(
                minted <= totalNativeSupply,
                "Cannot mint more than given supply."
            );
            id = minted;
        } else {
            id = availableIds[availableIds.length - 1];
            availableIds.pop();
        }

        if (_ownerOf[id] != address(0)) {
            revert AlreadyExists();
        }

        _deliverNFT(to, id);

        emit Transfer(address(0), to, id);
    }

    function _burnNFT(address from) internal virtual {
        if (from == address(0)) {
            revert InvalidSender();
        }

        // Indiscriminantly burn last NFT in list of owned NFTs for `from`
        uint256 id = _owned[from][_owned[from].length - 1];
        _owned[from].pop();
        delete _ownedIndex[id];
        delete _ownerOf[id];
        delete getApproved[id];

        availableIds.push(id);

        emit Transfer(from, address(0), id);
    }

    function _removeSpecificNFT(address from, uint256 id) private {
        uint256 lastId;
        if (_isContract(from)) {
            lastId = _contractOwned[from][_contractOwned[from].length - 1];
            _contractOwned[from][_ownedIndex[id]] = lastId;
            _contractOwned[from].pop();
        } else {
            lastId = _owned[from][_owned[from].length - 1];
            _owned[from][_ownedIndex[id]] = lastId;
            _owned[from].pop();
        }
        _ownedIndex[lastId] = _ownedIndex[id];
        delete getApproved[id];
    }

    function _deliverNFT(address to, uint256 id) private {
        _ownerOf[id] = to;
        if (_isContract(to)) {
            _contractOwned[to].push(id);
            _ownedIndex[id] = _contractOwned[to].length - 1;
        } else {
            _owned[to].push(id);
            _ownedIndex[id] = _owned[to].length - 1;
        }
    }

    function _setNameSymbol(string memory _name, string memory _symbol)
        internal
    {
        name = _name;
        symbol = _symbol;
    }

    function _shouldSkip(address a) private view returns (bool) {
        return whitelist[a] || _isContract(a);
    }

    function _isContract(address a) private view returns (bool result) {
        assembly {
            result := extcodesize(a)
        }
    }

    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

contract STONER404 is STONER, ERC165 {
    string public baseTokenURI;

    uint256 public maxMintable;
    uint256 public royaltyAmount;
    uint256 public maxMintPerTx;

    uint256 public price;

    address public royaltyReceiver;

    mapping(uint256 => mapping(address => uint256)) public phaseMintsRemaining;

    uint256 public phases;
    uint256 public phaseDuration;
    bool public paused;

    bytes4 private constant _INTERFACE_ID_ERC2981 = 0x2a55205a;

    bool private _mintActive;
    uint256 public startTime;

    constructor(
        address _owner,
        uint256 _startTime
    ) STONER("STONER404", "$STONER", 18, 420, _owner) {
        balanceOf[_owner] = 0 ether;

        whitelist[_owner] = true;
        price = 10 ether;

        maxMintable = 420;
        royaltyAmount = 250;
        _mintActive = false;
        maxMintPerTx = 420;
        startTime = _startTime;
        paused = false;
        royaltyReceiver = _owner;

        baseTokenURI = "ipfs://bafybeibrmm2ovy7aj3sqng256u3bzc2lvtywsmast5glwxs63actlbkenq/";

        phaseDuration = 600; // 10 minutes for each phase
        phases = 2;
    }

    function tokenURI(uint256 id) public view override returns (string memory) {
        return string.concat(baseTokenURI, Strings.toString(id));
    }

    function hasPhaseAccess(
        uint256 phase,
        address account
    ) public view returns (bool) {
        return phaseMintsRemaining[phase][account] > 0;
    }

    function canMintAmountInPhase(
        uint256 phase,
        address account,
        uint256 quantity
    ) public view returns (bool) {
        return phaseMintsRemaining[phase][account] >= quantity;
    }

    function activePhase() public view returns (uint256) {
        if (!mintHasStarted()) {
            return 0;
        } else {
            uint256 secondsPastStart = block.timestamp - startTime;
            uint256 phase = (secondsPastStart / phaseDuration) + 1;

            if (phase > phases) {
                return phases + 1; // +1 for public
            } else {
                return phase;
            }
        }
    }

    function mintHasStarted() public view returns (bool) {
        return block.timestamp >= startTime;
    }

    function secondsUntilStart() public view returns (uint256) {
        if (!mintHasStarted()) {
            return startTime - block.timestamp;
        } else {
            return 0;
        }
    }

    function mintActive() public view returns (bool) {
        return _mintActive || (block.timestamp >= startTime); // use timer w/ability to override
    }

    function mint(uint256 quantity) public payable {
        require(mintActive(), "Minting is not active.");
        require(!paused);

        require(quantity <= maxMintPerTx, "Cannot mint that many at once.");
        require(minted + quantity <= maxMintable, "Finished minting.");
        require(msg.value >= (quantity * price), "Not enough FTM sent.");

        for (uint256 phase = 1; phase <= phases; phase++) {
            if (activePhase() == phase) {
                require(
                    canMintAmountInPhase(phase, msg.sender, quantity),
                    string.concat(
                        "Currently in phase ",
                        Strings.toString(phase),
                        "."
                    )
                );
                phaseMintsRemaining[phase][msg.sender] -= quantity;
            }
        }

        if (msg.value > 0) {
            payable(owner).transfer(msg.value);
        }

        _mint(msg.sender, quantity);
    }

    // ROYALTIES

    function royaltyInfo(
        uint256 _tokenId,
        uint256 _salePrice
    ) external view returns (address receiver, uint256 amount) {
        return (royaltyReceiver, ((_salePrice * royaltyAmount) / 10000));
    }

    function supportsInterface(
        bytes4 interfaceId
    ) public view virtual override(ERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            interfaceId == _INTERFACE_ID_ERC2981 ||
            super.supportsInterface(interfaceId);
    }

    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual override {
        super._beforeTokenTransfer(from, to, amount);

        if (activePhase() <= phases) {
            // still within a mint phase
            require(
                from == owner || to == owner,
                "Cannot transfer until mint enters public."
            );
            return;
        } else if (
            block.timestamp < (startTime + (phases * phaseDuration) + 180)
        ) {
            // 3 minutes of anti-whale when trading goes live
            require(
                balanceOf[to] <= ((5 * totalSupply) / 1000),
                "No more than 0.5% at this stage."
            );
            return;
        }
    }

    // admin

    function ownerMint(address recipient, uint256 quantity) public onlyOwner {
        _mint(recipient, quantity);
    }

    function grantPhaseAccess(
        uint256 phase,
        address[] memory accounts,
        uint256 quantity
    ) public onlyOwner {
        for (uint256 i = 0; i < accounts.length; i++) {
            phaseMintsRemaining[phase][accounts[i]] += quantity;
        }
    }

    function setPaused(bool _paused) public onlyOwner {
        paused = _paused;
    }

    function setMintActive(bool mintActive_) public onlyOwner {
        _mintActive = mintActive_;
    }

    function setRoyaltyReceiver(address _receiver) public onlyOwner {
        royaltyReceiver = _receiver;
    }

    function setStartTime(uint256 _startTime) public onlyOwner {
        startTime = _startTime;
    }

    function setRoyaltyAmount(uint256 _royaltyAmount) public onlyOwner {
        royaltyAmount = _royaltyAmount;
    }

    function setBaseURI(string memory _baseURI) public onlyOwner {
        baseTokenURI = _baseURI;
    }

    function setMaxPerTx(uint256 _maxMintPerTx) public onlyOwner {
        maxMintPerTx = _maxMintPerTx;
    }

    function setPrice(uint256 _price) public onlyOwner {
        price = _price;
    }
}

abstract contract ERC721Receiver {
    function onERC721Received(
        address,
        address,
        uint256,
        bytes calldata
    ) external virtual returns (bytes4) {
        return ERC721Receiver.onERC721Received.selector;
    }
}

// OpenZeppelin Contracts (last updated v5.0.0) (utils/Strings.sol)


/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant HEX_DIGITS = "0123456789abcdef";
    uint8 private constant ADDRESS_LENGTH = 20;

    /**
     * @dev The `value` string doesn't fit in the specified `length`.
     */
    error StringsInsufficientHexLength(uint256 value, uint256 length);

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), HEX_DIGITS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toStringSigned(int256 value) internal pure returns (string memory) {
        return string.concat(value < 0 ? "-" : "", toString(SignedMath.abs(value)));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        uint256 localValue = value;
        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_DIGITS[localValue & 0xf];
            localValue >>= 4;
        }
        if (localValue != 0) {
            revert StringsInsufficientHexLength(value, length);
        }
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal
     * representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), ADDRESS_LENGTH);
    }

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return bytes(a).length == bytes(b).length && keccak256(bytes(a)) == keccak256(bytes(b));
    }
}

// OpenZeppelin Contracts (last updated v5.0.0) (utils/math/Math.sol)

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    /**
     * @dev Muldiv operation overflow.
     */
    error MathOverflowedMulDiv();

    enum Rounding {
        Floor, // Toward negative infinity
        Ceil, // Toward positive infinity
        Trunc, // Toward zero
        Expand // Away from zero
    }

    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds towards infinity instead
     * of rounding towards zero.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        if (b == 0) {
            // Guarantee the same behavior as in a regular Solidity division.
            return a / b;
        }

        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or
     * denominator == 0.
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv) with further edits by
     * Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0 = x * y; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            if (denominator <= prod1) {
                revert MathOverflowedMulDiv();
            }

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator.
            // Always >= 1. See https://cs.stackexchange.com/q/138556/92363.

            uint256 twos = denominator & (0 - denominator);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also
            // works in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (unsignedRoundsUp(rounding) && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded
     * towards zero.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (unsignedRoundsUp(rounding) && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (unsignedRoundsUp(rounding) && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (unsignedRoundsUp(rounding) && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (unsignedRoundsUp(rounding) && 1 << (result << 3) < value ? 1 : 0);
        }
    }

    /**
     * @dev Returns whether a provided rounding mode is considered rounding up for unsigned integers.
     */
    function unsignedRoundsUp(Rounding rounding) internal pure returns (bool) {
        return uint8(rounding) % 2 == 1;
    }
}
// OpenZeppelin Contracts (last updated v5.0.0) (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`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon
     *   a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must 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: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
     * or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
     * understand this adds an external call which potentially creates a reentrancy vulnerability.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 tokenId) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the address zero.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool approved) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// OpenZeppelin Contracts (last updated v5.0.0) (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);
}