// SPDX-License-Identifier: MIT

pragma solidity 0.8.11;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

interface IDexPair {
    function sync() external;
}

interface IERC20 {
    /**
     * @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 `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @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
    );
}

interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

contract ERC20 is Context, IERC20, IERC20Metadata {
    using SafeMath for uint256;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string public _name;
    string public _symbol;

    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function name() public view virtual override returns (string memory) {
        return _name;
    }

    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account)
        public
        view
        virtual
        override
        returns (uint256)
    {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount)
        public
        virtual
        override
        returns (bool)
    {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function allowance(address owner, address spender)
        public
        view
        virtual
        override
        returns (uint256)
    {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount)
        public
        virtual
        override
        returns (bool)
    {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(
            currentAllowance >= amount,
            "ERC20: transfer amount exceeds allowance"
        );
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue)
        public
        virtual
        returns (bool)
    {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender] + addedValue
        );
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue)
        public
        virtual
        returns (bool)
    {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(
            currentAllowance >= subtractedValue,
            "ERC20: decreased allowance below zero"
        );
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        uint256 senderBalance = _balances[sender];
        require(
            senderBalance >= amount,
            "ERC20: transfer amount exceeds balance"
        );
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);
    }

    function _createInitialSupply(address account, uint256 amount)
        internal
        virtual
    {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);
    }

    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _balances[account] = _balances[account].sub(
            amount,
            "ERC20: burn amount exceeds balance"
        );
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
}

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() {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view 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() external virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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) external virtual onlyOwner {
        require(
            newOwner != address(0),
            "Ownable: new owner is the zero address"
        );
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // 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 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

interface IDexRouter {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        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 addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );
}

interface IDexFactory {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}

contract BurnInu is ERC20, Ownable {
    using SafeMath for uint256;

    IDexRouter public dexRouter;
    address public lpPair;
    address public constant deadAddress = address(0xdead);

    bool private swapping;

    address public marketingWallet;
    address public devWallet;

    uint256 private blockPenalty;

    uint256 public tradingActiveBlock = 0; // 0 means trading is not active

    uint256 public maxTxnAmount;
    uint256 public swapTokensAtAmount;
    uint256 public maxWallet;

    uint256 public amountForAutoBuyBack = 0.2 ether;
    bool public autoBuyBackEnabled = true;
    uint256 public autoBuyBackFrequency = 3600 seconds;
    uint256 public lastAutoBuyBackTime;

    uint256 public percentForLPBurn = 100; // 100 = 1%
    bool public lpBurnEnabled = true;
    uint256 public lpBurnFrequency = 3600 seconds;
    uint256 public lastLpBurnTime;

    uint256 public manualBurnFrequency = 1 hours;
    uint256 public lastManualLpBurnTime;

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;

    // Anti-bot and anti-whale mappings and variables
    mapping(address => uint256) private _holderLastTransferBlock;
    bool public transferDelayEnabled = true;

    uint256 public buyTotalFees;
    uint256 public buyMarketingFee;
    uint256 public buyLiquidityFee;
    uint256 public buyBuyBackFee;
    uint256 public buyDevFee;
    uint256 public buyBurnFee;

    uint256 public sellTotalFees;
    uint256 public sellMarketingFee;
    uint256 public sellLiquidityFee;
    uint256 public sellBuyBackFee;
    uint256 public sellDevFee;
    uint256 public sellBurnFee;

    uint256 public tokensForMarketing;
    uint256 public tokensForLiquidity;
    uint256 public tokensForBuyBack;
    uint256 public tokensForDev;
    uint256 public tokensForBurn;

    uint256 public delayBlock = 3;
    address private tokenOwner;

    /******************/

    // exlcude from fees and max transaction amount
    mapping(address => bool) private _isExcludedFromFees;
    mapping(address => bool) public _isExcludedmaxTxnAmount;

    // store addresses that a automatic market maker pairs. Any transfer *to* these addresses
    // could be subject to a maximum transfer amount
    mapping(address => bool) public automatedMarketMakerPairs;

    event ExcludeFromFees(address indexed account, bool isExcluded);

    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

    event MarketingWalletUpdated(
        address indexed newWallet,
        address indexed oldWallet
    );

    event DevWalletUpdated(
        address indexed newWallet,
        address indexed oldWallet
    );

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiquidity
    );

    event AutoNukeLP(uint256 amount);

    event ManualNukeLP(uint256 amount);

    event BuyBackTriggered(uint256 amount);

    event OwnerForcedSwapBack(uint256 timestamp);

    constructor(address newOwner, address marketingOwner)
        payable
        ERC20("Burn Inu", "BINU")
    {
        uint256 _buyMarketingFee = 4;
        uint256 _buyLiquidityFee = 1;
        uint256 _buyBuyBackFee = 1;
        uint256 _buyDevFee = 1;
        uint256 _buyBurnFee = 3;

        uint256 _sellMarketingFee = 3;
        uint256 _sellLiquidityFee = 3;
        uint256 _sellBuyBackFee = 2;
        uint256 _sellDevFee = 2;
        uint256 _sellBurnFee = 4;

        uint256 totalSupply = 1 * 1e9 * 1e18;

        //update name/ticker
        _name = "Burn Inu";
        _symbol = "BINU";

        tokenOwner = newOwner;

        maxTxnAmount = (totalSupply * 5) / 1000; // 0.5% of supply
        maxWallet = (totalSupply * 1) / 100; // 1% maxWallet
        swapTokensAtAmount = (totalSupply * 5) / 10000; // 0.05% swap amount

        buyMarketingFee = _buyMarketingFee;
        buyLiquidityFee = _buyLiquidityFee;
        buyBuyBackFee = _buyBuyBackFee;
        buyDevFee = _buyDevFee;
        buyBurnFee = _buyBurnFee;
        buyTotalFees =
            buyMarketingFee +
            buyLiquidityFee +
            buyBuyBackFee +
            buyDevFee +
            buyBurnFee;

        sellMarketingFee = _sellMarketingFee;
        sellLiquidityFee = _sellLiquidityFee;
        sellBuyBackFee = _sellBuyBackFee;
        sellDevFee = _sellDevFee;
        sellBurnFee = _sellBurnFee;
        sellTotalFees =
            sellMarketingFee +
            sellLiquidityFee +
            sellBuyBackFee +
            sellDevFee +
            sellBurnFee;

        marketingWallet = address(marketingOwner); // set as marketing wallet
        devWallet = address(msg.sender);

        // exclude from paying fees or having max transaction amount
        excludeFromFees(owner(), true);
        excludeFromFees(marketingWallet, true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);
        excludeFromFees(tokenOwner, true); // future owner wallet

        excludeFromMaxTransaction(owner(), true);
        excludeFromMaxTransaction(marketingWallet, true);
        excludeFromMaxTransaction(address(this), true);
        excludeFromMaxTransaction(address(0xdead), true);
        excludeFromMaxTransaction(tokenOwner, true);

        /*
            _createInitialSupply is an internal function that is only called here,
            and CANNOT be called ever again
        */

        _createInitialSupply(tokenOwner, (totalSupply * 5) / 100);
        _createInitialSupply(address(this), (totalSupply * 95) / 100);
    }

    receive() external payable {}

    // remove limits after token is stable
    function removeLimits() external onlyOwner {
        limitsInEffect = false;
    }

    // disable Transfer delay - cannot be reenabled
    function disableTransferDelay() external onlyOwner {
        transferDelayEnabled = false;
    }

    // change the minimum amount of tokens to sell from fees
    function updateSwapTokensAtAmount(uint256 newAmount)
        external
        onlyOwner
        returns (bool)
    {
        require(
            newAmount >= (totalSupply() * 1) / 100000,
            "Swap amount cannot be lower than 0.001% total supply."
        );
        require(
            newAmount <= (totalSupply() * 1) / 100000,
            "Swap amount cannot be higher than 0.5% total supply."
        );
        swapTokensAtAmount = newAmount;
        return true;
    }

    function updateMaxTxnAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 1) / 100) / 1e18,
            "Cannot set maxTxnAmount lower than 1%"
        );
        maxTxnAmount = newNum * (10**18);
    }

    function updateMaxWalletAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 1) / 100) / 1e18,
            "Cannot set maxWallet lower than 1%"
        );
        maxWallet = newNum * (10**18);
    }

    function excludeFromMaxTransaction(address updAds, bool isEx)
        public
        onlyOwner
    {
        _isExcludedmaxTxnAmount[updAds] = isEx;
    }

    // only use to disable contract sales if absolutely necessary (emergency use only)
    function updateSwapEnabled(bool enabled) external onlyOwner {
        swapEnabled = enabled;
    }

    function updateBuyFees(
        uint256 _marketingFee,
        uint256 _liquidityFee,
        uint256 _buyBackFee,
        uint256 _devFee,
        uint256 _burnFee
    ) external onlyOwner {
        buyMarketingFee = _marketingFee;
        buyLiquidityFee = _liquidityFee;
        buyBuyBackFee = _buyBackFee;
        buyDevFee = _devFee;
        buyBurnFee = _burnFee;

        buyTotalFees =
            buyMarketingFee +
            buyLiquidityFee +
            buyBuyBackFee +
            buyDevFee +
            buyBurnFee;
        require(buyTotalFees <= 20, "Must keep fees at 20% or less");
    }

    function updateSellFees(
        uint256 _marketingFee,
        uint256 _liquidityFee,
        uint256 _buyBackFee,
        uint256 _devFee,
        uint256 _burnFee
    ) external onlyOwner {
        sellMarketingFee = _marketingFee;
        sellLiquidityFee = _liquidityFee;
        sellBuyBackFee = _buyBackFee;
        sellDevFee = _devFee;
        sellBurnFee = _burnFee;

        sellTotalFees =
            sellMarketingFee +
            sellLiquidityFee +
            sellBuyBackFee +
            sellDevFee +
            sellBurnFee;
        require(sellTotalFees <= 25, "Must keep fees at 25% or less");
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function setAutomatedMarketMakerPair(address pair, bool value)
        public
        onlyOwner
    {
        require(
            pair != lpPair,
            "The pair cannot be removed from automatedMarketMakerPairs"
        );

        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        automatedMarketMakerPairs[pair] = value;

        emit SetAutomatedMarketMakerPair(pair, value);
    }

    function updateMarketingWallet(address newMarketingWallet)
        external
        onlyOwner
    {
        emit MarketingWalletUpdated(newMarketingWallet, marketingWallet);
        marketingWallet = newMarketingWallet;
    }

    function updateDevWallet(address newWallet) external onlyOwner {
        emit DevWalletUpdated(newWallet, devWallet);
        devWallet = newWallet;
    }

    function isExcludedFromFees(address account) public view returns (bool) {
        return _isExcludedFromFees[account];
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        if (amount == 0) {
            super._transfer(from, to, 0);
            return;
        }

        if (!tradingActive) {
            require(
                _isExcludedFromFees[from] || _isExcludedFromFees[to],
                "Trading is not active."
            );
        }

        if (limitsInEffect) {
            if (
                from != owner() &&
                to != owner() &&
                to != address(0) &&
                to != address(0xdead) &&
                !swapping &&
                !_isExcludedFromFees[to] &&
                !_isExcludedFromFees[from]
            ) {
                if (transferDelayEnabled) {
                    if (to != address(dexRouter) && to != address(lpPair)) {
                        require(
                            _holderLastTransferBlock[tx.origin] <
                                block.number - delayBlock &&
                                _holderLastTransferBlock[to] <
                                block.number - delayBlock,
                            "_transfer:: Transfer Delay enabled.  Try again later."
                        );
                        _holderLastTransferBlock[tx.origin] = block.number;
                        _holderLastTransferBlock[to] = block.number;
                    }
                }

                //when buy
                if (
                    automatedMarketMakerPairs[from] &&
                    !_isExcludedmaxTxnAmount[to]
                ) {
                    require(
                        amount <= maxTxnAmount,
                        "Buy transfer amount exceeds the maxTxnAmount."
                    );
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
                //when sell
                else if (
                    automatedMarketMakerPairs[to] &&
                    !_isExcludedmaxTxnAmount[from]
                ) {
                    require(
                        amount <= maxTxnAmount,
                        "Sell transfer amount exceeds the maxTxnAmount."
                    );
                } else if (!_isExcludedmaxTxnAmount[to]) {
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
            }
        }

        uint256 contractTokenBalance = balanceOf(address(this));

        bool canSwap = contractTokenBalance >= swapTokensAtAmount;

        if (
            canSwap &&
            swapEnabled &&
            !swapping &&
            !automatedMarketMakerPairs[from] &&
            !_isExcludedFromFees[from] &&
            !_isExcludedFromFees[to]
        ) {
            swapping = true;

            swapBack();

            swapping = false;
        }

        if (
            !swapping &&
            automatedMarketMakerPairs[to] &&
            lpBurnEnabled &&
            block.timestamp >= lastLpBurnTime + lpBurnFrequency &&
            !_isExcludedFromFees[from]
        ) {
            autoBurnLiquidityPairTokens();
        }

        if (
            !swapping &&
            automatedMarketMakerPairs[to] &&
            autoBuyBackEnabled &&
            block.timestamp >= lastAutoBuyBackTime + autoBuyBackFrequency &&
            !_isExcludedFromFees[from] &&
            address(this).balance >= amountForAutoBuyBack
        ) {
            autoBuyBack(amountForAutoBuyBack);
        }

        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) {
            // bot/sniper penalty.  Tokens get transferred to marketing wallet to allow potential refund.
            if (isPenaltyActive() && automatedMarketMakerPairs[from]) {
                fees = (amount * 99) / 100;
                tokensForLiquidity += (fees * sellLiquidityFee) / sellTotalFees;
                tokensForBuyBack += (fees * sellBuyBackFee) / sellTotalFees;
                tokensForMarketing += (fees * sellMarketingFee) / sellTotalFees;
                tokensForDev += (fees * sellDevFee) / sellTotalFees;
            }
            // on sell
            else if (automatedMarketMakerPairs[to] && sellTotalFees > 0) {
                fees = (amount * sellTotalFees) / 100;
                tokensForLiquidity += (fees * sellLiquidityFee) / sellTotalFees;
                tokensForBuyBack += (fees * sellBuyBackFee) / sellTotalFees;
                tokensForMarketing += (fees * sellMarketingFee) / sellTotalFees;
                tokensForDev += (fees * sellDevFee) / sellTotalFees;

                //Burnomics
                tokensForBurn += (fees * sellBurnFee) / sellTotalFees;
            }
            // on buy
            else if (automatedMarketMakerPairs[from] && buyTotalFees > 0) {
                fees = (amount * buyTotalFees) / 100;
                tokensForLiquidity += (fees * buyLiquidityFee) / buyTotalFees;
                tokensForBuyBack += (fees * buyBuyBackFee) / buyTotalFees;
                tokensForMarketing += (fees * buyMarketingFee) / buyTotalFees;
                tokensForDev += (fees * buyDevFee) / buyTotalFees;

                //Burnomics
                tokensForBurn += (fees * buyBurnFee) / buyTotalFees;
            }

            if (fees > 0) {
                super._transfer(from, address(this), fees);

                if (tokensForBurn > 0) {
                    _burn(address(this), tokensForBurn);
                    tokensForBurn = 0;
                }
            }

            amount -= fees;
        }

        super._transfer(from, to, amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = dexRouter.WETH();

        _approve(address(this), address(dexRouter), tokenAmount);

        // make the swap
        dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(dexRouter), tokenAmount);

        // add the liquidity
        dexRouter.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            deadAddress,
            block.timestamp
        );
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        uint256 totalTokensToSwap = tokensForLiquidity +
            tokensForMarketing +
            tokensForBuyBack +
            tokensForDev;
        bool success;

        if (contractBalance == 0 || totalTokensToSwap == 0) {
            return;
        }

        if (contractBalance > swapTokensAtAmount * 20) {
            contractBalance = swapTokensAtAmount * 20;
        }

        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = (contractBalance * tokensForLiquidity) /
            totalTokensToSwap /
            2;
        uint256 amountToSwapForETH = contractBalance - liquidityTokens;

        uint256 initialETHBalance = address(this).balance;

        swapTokensForEth(amountToSwapForETH);

        uint256 ethBalance = address(this).balance - initialETHBalance;

        uint256 ethForMarketing = (ethBalance * tokensForMarketing) /
            (totalTokensToSwap - (tokensForLiquidity / 2));
        uint256 ethForBuyBack = (ethBalance * tokensForBuyBack) /
            (totalTokensToSwap - (tokensForLiquidity / 2));
        uint256 ethForDev = (ethBalance * tokensForDev) /
            (totalTokensToSwap - (tokensForLiquidity / 2));

        uint256 ethForLiquidity = ethBalance -
            ethForMarketing -
            ethForBuyBack -
            ethForDev;

        tokensForLiquidity = 0;
        tokensForMarketing = 0;
        tokensForBuyBack = 0;
        tokensForDev = 0;

        (success, ) = address(devWallet).call{value: ethForDev}("");
        (success, ) = address(marketingWallet).call{value: ethForMarketing}("");

        if (liquidityTokens > 0 && ethForLiquidity > 0) {
            addLiquidity(liquidityTokens, ethForLiquidity);
            emit SwapAndLiquify(
                amountToSwapForETH,
                ethForLiquidity,
                tokensForLiquidity
            );
        }

        // keep leftover ETH for buyback
    }

    // force Swap back if slippage issues.
    function forceSwapBack() external onlyOwner {
        require(
            balanceOf(address(this)) >= swapTokensAtAmount,
            "Can only swap when token amount is at or higher than restriction"
        );
        swapping = true;
        swapBack();
        swapping = false;
        emit OwnerForcedSwapBack(block.timestamp);
    }

    // useful for buybacks or to reclaim any ETH on the contract in a way that helps holders.
    function buyBackTokens(uint256 amountInWei) external onlyOwner {
        require(
            amountInWei <= 10 ether,
            "May not buy more than 10 ETH in a single buy to reduce sandwich attacks"
        );

        address[] memory path = new address[](2);
        path[0] = dexRouter.WETH();
        path[1] = address(this);

        // make the swap
        dexRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{
            value: amountInWei
        }(
            0, // accept any amount of Ethereum
            path,
            address(0xdead),
            block.timestamp
        );
        emit BuyBackTriggered(amountInWei);
    }

    function setAutoBuyBackSettings(
        uint256 _frequencyInSeconds,
        uint256 _buyBackAmount,
        bool _autoBuyBackEnabled
    ) external onlyOwner {
        require(
            _frequencyInSeconds >= 30,
            "cannot set buyback more often than every 30 seconds"
        );
        require(
            _buyBackAmount <= 2 ether && _buyBackAmount >= 0.05 ether,
            "Must set auto buyback amount between .05 and 2 ETH"
        );
        autoBuyBackFrequency = _frequencyInSeconds;
        amountForAutoBuyBack = _buyBackAmount;
        autoBuyBackEnabled = _autoBuyBackEnabled;
    }

    function setAutoLPBurnSettings(
        uint256 _frequencyInSeconds,
        uint256 _percent,
        bool _Enabled
    ) external onlyOwner {
        require(
            _frequencyInSeconds >= 600,
            "cannot set buyback more often than every 10 minutes"
        );
        require(
            _percent <= 1000 && _percent >= 0,
            "Must set auto LP burn percent between 1% and 10%"
        );
        lpBurnFrequency = _frequencyInSeconds;
        percentForLPBurn = _percent;
        lpBurnEnabled = _Enabled;
    }

    // automated buyback
    function autoBuyBack(uint256 amountInWei) internal {
        lastAutoBuyBackTime = block.timestamp;

        address[] memory path = new address[](2);
        path[0] = dexRouter.WETH();
        path[1] = address(this);

        // make the swap
        dexRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{
            value: amountInWei
        }(
            0, // accept any amount of Ethereum
            path,
            address(0xdead),
            block.timestamp
        );

        emit BuyBackTriggered(amountInWei);
    }

    function isPenaltyActive() public view returns (bool) {
        return tradingActiveBlock >= block.number - blockPenalty;
    }

    function autoBurnLiquidityPairTokens() internal {
        lastLpBurnTime = block.timestamp;

        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(lpPair);

        // calculate amount to burn
        uint256 amountToBurn = (liquidityPairBalance * percentForLPBurn) /
            10000;

        if (amountToBurn > 0) {
            super._transfer(lpPair, address(0xdead), amountToBurn);
        }

        //sync price since this is not in a swap transaction!
        IDexPair pair = IDexPair(lpPair);
        pair.sync();
        emit AutoNukeLP(amountToBurn);
    }

    function manualBurnLiquidityPairTokens(uint256 percent) external onlyOwner {
        require(
            block.timestamp > lastManualLpBurnTime + manualBurnFrequency,
            "Must wait for cooldown to finish"
        );
        require(percent <= 1000, "May not nuke more than 10% of tokens in LP");
        lastManualLpBurnTime = block.timestamp;

        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(lpPair);

        // calculate amount to burn
        uint256 amountToBurn = (liquidityPairBalance * percent) / 10000;

        if (amountToBurn > 0) {
            super._transfer(lpPair, address(0xdead), amountToBurn);
        }

        //sync price since this is not in a swap transaction!
        IDexPair pair = IDexPair(lpPair);
        pair.sync();
        emit ManualNukeLP(amountToBurn);
    }

    function launch(uint256 _blockPenalty) external onlyOwner {
        require(!tradingActive, "Trading is already active, cannot relaunch.");

        blockPenalty = _blockPenalty;

        //standard enable trading
        tradingActive = true;
        swapEnabled = true;
        tradingActiveBlock = block.number;
        lastLpBurnTime = block.timestamp;

        // initialize router
        IDexRouter _dexRouter = IDexRouter(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );
        dexRouter = _dexRouter;

        // create pair
        lpPair = IDexFactory(_dexRouter.factory()).createPair(
            address(this),
            _dexRouter.WETH()
        );
        excludeFromMaxTransaction(address(lpPair), true);
        _setAutomatedMarketMakerPair(address(lpPair), true);

        // add the liquidity
        require(
            address(this).balance > 0,
            "Must have ETH on contract to launch"
        );
        require(
            balanceOf(address(this)) > 0,
            "Must have Tokens on contract to launch"
        );
        _approve(address(this), address(dexRouter), balanceOf(address(this)));
        dexRouter.addLiquidityETH{value: address(this).balance}(
            address(this),
            balanceOf(address(this)),
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            tokenOwner,
            block.timestamp
        );
    }

    // withdraw ETH if stuck before launch
    function withdrawStuckETH() external onlyOwner {
        require(!tradingActive, "Can only withdraw if trading hasn't started");
        bool success;
        (success, ) = address(msg.sender).call{value: address(this).balance}(
            ""
        );
    }
}