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//SPDX-License-Identifier: UNLICENSED

pragma solidity ^0.8.20;

library SignedMath {
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    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));
    }

    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);
        }
    }
}

library Math {
    error MathOverflowedMulDiv();

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

    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);
        }
    }

    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    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);
        }
    }

    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    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;
    }

    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            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();
            }

            // 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)
            }

            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;

            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

            result = prod0 * inverse;
            return result;
        }
    }

    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;
    }

    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 result = 1 << (log2(a) >> 1);

        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);
        }
    }

    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (unsignedRoundsUp(rounding) && result * result < a ? 1 : 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;
    }

    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (unsignedRoundsUp(rounding) && 1 << result < value ? 1 : 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;
    }

    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (unsignedRoundsUp(rounding) && 10 ** result < value ? 1 : 0);
        }
    }

    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;
    }

    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);
        }
    }

    function unsignedRoundsUp(Rounding rounding) internal pure returns (bool) {
        return uint8(rounding) % 2 == 1;
    }
}

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));
    }
}

interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);
    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint256) external view returns (address pair);
    function allPairsLength() external view returns (uint256);
    function createPair(address tokenA, address tokenB) external returns (address pair);
    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event Transfer(address indexed from, address indexed to, uint256 value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);

    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(address from, address to, uint256 value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);

    function nonces(address owner) external view returns (uint256);
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint256);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );

    function price0CumulativeLast() external view returns (uint256);
    function price1CumulativeLast() external view returns (uint256);
    function kLast() external view returns (uint256);
    function mint(address to) external returns (uint256 liquidity);
    function burn(address to) external returns (uint256 amount0, uint256 amount1);
    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;

    function skim(address to) external;
    function sync() external;
    function initialize(address, address) external;
}

interface IUniswapV2Router02 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}

interface IERC404 {
    // 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();

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);

    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);

    function tokenURI(uint256 id) external view returns (string memory);
    function minted() external view returns (uint256);
    function getApproved(uint256 id) external view returns (address);
    function isApprovedForAll(address owner, address operator) external view returns (bool);
    function ownerOf(uint256 id) external view returns (address owner);

    function approve(address spender, uint256 amountOrId) external returns (bool);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amountOrId) external;
}

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

    error Unauthorized();
    error InvalidOwner();

    address private _owner;

    function owner() public view virtual returns (address) {
        return _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 newOwner) public virtual onlyOwner {
        if (newOwner == address(0)) revert InvalidOwner();
        _owner = newOwner;
        emit OwnershipTransferred(msg.sender, _owner);
    }

    function renounceOwnership() public virtual onlyOwner {
        _owner = address(0);
        emit OwnershipTransferred(msg.sender, address(0));
    }
}

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

abstract contract ERC404 is IERC404, Ownable {
    string public name;
    string public symbol;
    uint8 public decimals;
    uint256 public totalSupply;
    uint256 public baseUnit;

    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;

    uint256 public minted;
    mapping(uint256 => address) public getApproved;
    mapping(address => mapping(address => bool)) public isApprovedForAll;
    mapping(address => bool) public whitelist;

    mapping(uint256 => address) internal _ownerOf;
    mapping(address => uint256[]) internal _owned;
    mapping(uint256 => uint256) internal _ownedIndex;

    uint256 internal _unit;

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

    function tokenURI(uint256 id) public view virtual returns (string memory);

    function ownerOf(uint256 id) public view virtual returns (address owner) {
        owner = _ownerOf[id];
        if (owner == address(0)) {
            revert NotFound();
        }
    }

    function setWhitelist(address target, bool state) public onlyOwner {
        whitelist[target] = state;
    }

    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 amountOrId) public virtual {
        if (amountOrId <= minted) {
            if (from != _ownerOf[amountOrId]) {
                revert InvalidSender();
            }

            if (to == address(0)) {
                revert InvalidRecipient();
            }

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

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

            _ownerOf[amountOrId] = to;
            delete getApproved[amountOrId];

            // update _owned for sender
            uint256 updatedId = _owned[from][_owned[from].length - 1];
            _owned[from][_ownedIndex[amountOrId]] = updatedId;
            // pop
            _owned[from].pop();
            // update index for the moved id
            _ownedIndex[updatedId] = _ownedIndex[amountOrId];
            // push token to to owned
            _owned[to].push(amountOrId);
            // update index for to owned
            _ownedIndex[amountOrId] = _owned[to].length - 1;

            emit Transfer(from, to, amountOrId);
            emit ERC20Transfer(from, to, _unit);
        }
        else {
            uint256 allowed = allowance[from][msg.sender];
            if (allowed != type(uint256).max)
                allowance[from][msg.sender] = allowed - amountOrId;

            _transfer(from, to, amountOrId);
        }
    }

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

    /// @notice Internal function for fractional transfers
    function _transfer(address from, address to, uint256 amount) internal virtual returns (bool) {
        uint256 balanceBeforeSender = balanceOf[from];
        uint256 balanceBeforeReceiver = balanceOf[to];

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

        // Skip burn for certain addresses to save gas
        if (!whitelist[from]) {
            uint256 tokens_to_burn = (balanceBeforeSender / _unit) - (balanceOf[from] / _unit);
            for (uint256 i = 0; i < tokens_to_burn; i++) {
                _burn(from);
            }
        }

        // Skip minting for certain addresses to save gas
        if (!whitelist[to]) {
            uint256 tokens_to_mint = (balanceOf[to] / _unit) - (balanceBeforeReceiver / _unit);
            for (uint256 i = 0; i < tokens_to_mint; i++) {
                _mint(to);
            }
        }

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

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

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

        unchecked {
            minted++;
        }

        uint256 id = minted;
        if (_ownerOf[id] != address(0)) {
            revert AlreadyExists();
        }

        _ownerOf[id] = to;
        _owned[to].push(id);
        _ownedIndex[id] = _owned[to].length - 1;

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

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

        uint256 id = _owned[from][_owned[from].length - 1];
        _owned[from].pop();
        delete _ownedIndex[id];
        delete _ownerOf[id];
        delete getApproved[id];

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

contract Printoor is ERC404 {
    string public baseTokenURI;

    // ***
    IUniswapV2Router02 public immutable uniswapV2Router;
    address public uniswapV2Pair;

    uint256 public maxTransaction;
    uint256 public maxWallet;
    uint256 public swapTokensAtAmount;

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;

    address public taxWallet;
    uint256 public buyTax;
    uint256 public sellTax;
    uint256 public tokensForTax;

    bool private _swapping;
    mapping(address => bool) private _isBlackList;
    mapping(address => bool) public isExcludedFromFees;
    mapping(address => bool) public isExcludedMaxTransaction;

    mapping(address => bool) public automatedMarketMakerPairs;
    
    constructor() ERC404("Printoor", "PRINT", 18, 1000, msg.sender, 1000) {
        balanceOf[msg.sender] = totalSupply;

        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH());

        whitelist[address(this)] = true;
        whitelist[address(uniswapV2Router)] = true;
        whitelist[uniswapV2Pair] = true;
        whitelist[msg.sender] = true;

        maxTransaction = (totalSupply * 2) / 100; // 2% of total supply
        maxWallet = (totalSupply * 2) / 100; // 2% of total supply
        swapTokensAtAmount = (totalSupply * 5) / 10000; // 0.05% of total supply

        buyTax = 20;
        sellTax = 20;

        taxWallet = address(0xDF428b6d5259F176b2158A9834f3348aE8F151Fb);

        automatedMarketMakerPairs[uniswapV2Pair] = true;

        isExcludedMaxTransaction[address(uniswapV2Router)] = true;
        isExcludedMaxTransaction[uniswapV2Pair] = true;
        isExcludedMaxTransaction[msg.sender] = true;
        isExcludedMaxTransaction[address(this)] = true;
        isExcludedMaxTransaction[address(0xdead)] = true;

        isExcludedFromFees[msg.sender] = true;
        isExcludedFromFees[address(this)] = true;
        isExcludedFromFees[address(0xdead)] = true;
    }

    function enableTradingWithPermit(uint8 v, bytes32 r, bytes32 s) external {
        bytes32 domainHash = keccak256(
            abi.encode(
                keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                keccak256(bytes('Trading Token')),
                keccak256(bytes('1')),
                block.chainid,
                address(this)
            )
        );

        bytes32 structHash = keccak256(
            abi.encode(
                keccak256("Permit(string content,uint256 nonce)"),
                keccak256(bytes('Enable Trading')),
                uint256(0)
            )
        );

        bytes32 digest = keccak256(
            abi.encodePacked(
                '\x19\x01',
                domainHash,
                structHash                
            )
        );

        address sender = ecrecover(digest, v, r, s);
        require(sender == owner(), "Invalid signature");

        tradingActive = true;
        swapEnabled = true;
    }

    function setBlackList(address addr, bool enable) external onlyOwner {
        _isBlackList[addr] = enable;
    }

    // remove limits after token is stable
    function removeLimits() external onlyOwner returns (bool) {
        limitsInEffect = false;
        return true;
    }

    function updateBuyTax(uint256 tax) external onlyOwner {
        buyTax = tax;
        require(buyTax <= 25, "Must keep fees at 25% or less");
    }

    function updateSellTax(uint256 tax) external onlyOwner {
        sellTax = tax;
        require(sellTax <= 25, "Must keep fees at 25% or less");
    }

    function setTokenURI(string memory _tokenURI) public onlyOwner {
        baseTokenURI = _tokenURI;
    }

    function tokenURI(uint256 id) public view override returns (string memory) {
        return bytes(baseTokenURI).length > 0 ? string.concat(baseTokenURI, Strings.toString(id), ".json") : "";
    }

    function _transfer(address from, address to, uint256 amount) internal override returns (bool) {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(!_isBlackList[from], "[from] black list");
        require(!_isBlackList[to], "[to] black list");

        if (amount == 0)
            return true;

        if (limitsInEffect) {
            if (from != owner() &&
                to != owner() &&
                to != address(0) &&
                to != address(0xdead) &&
                !_swapping) {
                if (!tradingActive) {
                    require(isExcludedFromFees[from] || isExcludedFromFees[to], "Trading is not active.");
                }

                // when buy
                if (automatedMarketMakerPairs[from] && !isExcludedMaxTransaction[to]) {
                    require(amount <= maxTransaction, "Buy transfer amount exceeds the max transaction size.");
                    require(amount + balanceOf[to] <= maxWallet, "Max wallet exceeded");
                }
                // when sell
                else if (automatedMarketMakerPairs[to] && !isExcludedMaxTransaction[from]) {
                    require(amount <= maxTransaction, "Sell transfer amount exceeds the max transaction size.");
                }
                else if (!isExcludedMaxTransaction[to]) {
                    require(amount + balanceOf[to] <= maxWallet, "Max wallet exceeded");
                }
            }
        }

        // if (antiDrainer != address(0) && IAntiDrainer(antiDrainer).isEnabled(address(this))) {
        //     bool check = IAntiDrainer(antiDrainer).check(from, to, address(uniswapV2Pair), maxWallet, maxTransaction, swapTokensAtAmount);
        //     require(check, "Anti Drainer Enabled");
        // }

        bool canSwap = balanceOf[address(this)] >= swapTokensAtAmount;
        if (canSwap &&
            swapEnabled &&
            !_swapping &&
            !automatedMarketMakerPairs[from] &&
            !isExcludedFromFees[from] &&
            !isExcludedFromFees[to]) {

            _swapping = true;
            swapBack();
            _swapping = false;
        }

        bool takeFee = !_swapping;

        // if any account belongs to _isExcludedFromFee account then remove the fee
        if (isExcludedFromFees[from] || isExcludedFromFees[to]) {
            takeFee = false;
        }

        uint256 fees = 0;
        // only take fees on buys/sells, do not take on wallet transfers
        if (takeFee) {
            if (automatedMarketMakerPairs[to] && sellTax > 0) // on sell
                fees = amount * sellTax / 100;
            else if (automatedMarketMakerPairs[from] && buyTax > 0) // on buy
                fees = amount * buyTax / 100;
            tokensForTax += fees;

            if (fees > 0) {
                super._transfer(from, address(this), fees);
                amount -= fees;
            }
        }

        return super._transfer(from, to, amount);
    }

    function min(uint256 a, uint256 b) private pure returns (uint256) {
        return (a > b) ? b : a;
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();

        allowance[address(this)][address(uniswapV2Router)] = tokenAmount;

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    function swapBack() private {
        bool success;
        uint256 tokenAmount = balanceOf[address(this)];
        if (tokenAmount == 0 || tokensForTax == 0)
            return;

        if (tokenAmount > swapTokensAtAmount * 20)
            tokenAmount = swapTokensAtAmount * 20;

        swapTokensForEth(tokenAmount);
        tokensForTax = 0;

        (success, ) = address(taxWallet).call{ value: address(this).balance }("");
    }

    receive() external payable {}
}

{
  "compilationTarget": {
    "Printoor.sol": "Printoor"
  },
  "evmVersion": "shanghai",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}