// SPDX-License-Identifier: MIT
pragma solidity 0.8.18;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this;
        return msg.data;
    }
}

interface IERC20 {
    function totalSupply() external view returns (uint256);

    function balanceOf(address account) external view returns (uint256);

    function transfer(
        address recipient,
        uint256 amount
    ) external returns (bool);

    function allowance(
        address owner,
        address spender
    ) external view returns (uint256);

    function approve(address spender, uint256 amount) external returns (bool);

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);
}

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;

    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 _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
    );

    constructor() {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    function owner() public view returns (address) {
        return _owner;
    }

    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    function renounceOwnership() external virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(
            newOwner != address(0),
            "Ownable: new owner is the zero address"
        );
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

interface IDexRouter {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;

    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 FuckAzuki is ERC20, Ownable {
    uint256 public maxBuyAmount;
    uint256 public maxSellAmount;
    uint256 public maxWalletAmount;

    IDexRouter public immutable uniswapV2Router;
    address public immutable uniswapV2Pair;

    bool private swapping;
    uint256 public swapTokensAtAmount;

    address public TreasuryAddress;

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;

    uint256 public buyTotalFees;
    uint256 public buyTreasuryFee;
    uint256 public buyLiquidityFee;

    uint256 public sellTotalFees;
    uint256 public sellTreasuryFee;
    uint256 public sellLiquidityFee;

    uint256 public tokensForTreasury;
    uint256 public tokensForLiquidity;

    // exlcude from fees and max transaction amount
    mapping(address => bool) private _isExcludedFromFees;
    mapping(address => bool) public _isExcludedMaxTransactionAmount;

    // 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 SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);
    event EnabledTrading(bool tradingActive);
    event RemovedLimits();
    event ExcludeFromFees(address indexed account, bool isExcluded);
    event UpdatedMaxBuyAmount(uint256 newAmount);
    event UpdatedMaxSellAmount(uint256 newAmount);
    event UpdatedMaxWalletAmount(uint256 newAmount);
    event UpdatedTreasuryAddress(address indexed newWallet);
    event UpdatedRewardsAddress(address indexed newWallet);
    event MaxTransactionExclusion(address _address, bool excluded);
    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiquidity
    );

    constructor() ERC20("FKAZUKI", "FKAZUKI") {
        address newOwner = msg.sender;

        IDexRouter _uniswapV2Router = IDexRouter(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );

        _excludeFromMaxTransaction(address(_uniswapV2Router), true);
        uniswapV2Router = _uniswapV2Router;

        uniswapV2Pair = IDexFactory(_uniswapV2Router.factory()).createPair(
            address(this),
            _uniswapV2Router.WETH()
        );
        _setAutomatedMarketMakerPair(address(uniswapV2Pair), true);

        uint256 totalSupply = 1000000000 * 1e18;

        maxBuyAmount = 1000000000 * 1e18;
        maxSellAmount = 1000000000 * 1e18;
        maxWalletAmount = 1000000000 * 1e18;
        swapTokensAtAmount = (totalSupply * 50) / 100000;

        buyTreasuryFee = 15;
        buyLiquidityFee = 0;
        buyTotalFees = buyTreasuryFee + buyLiquidityFee;

        sellTreasuryFee = 30;
        sellLiquidityFee = 0;
        sellTotalFees = sellTreasuryFee + sellLiquidityFee;

        _excludeFromMaxTransaction(newOwner, true);
        _excludeFromMaxTransaction(address(this), true);
        _excludeFromMaxTransaction(address(0xdead), true);

        TreasuryAddress = address(msg.sender);

        excludeFromFees(newOwner, true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);

        _createInitialSupply(newOwner, totalSupply);
        transferOwnership(newOwner);
    }

    receive() external payable {}

    function updateMaxBuyAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 1) / 1000) / 1e18,
            "Cannot set max buy amount lower than 0.1%"
        );
        maxBuyAmount = newNum * (10 ** 18);
        emit UpdatedMaxBuyAmount(maxBuyAmount);
    }

    function updateMaxSellAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 1) / 1000) / 1e18,
            "Cannot set max sell amount lower than 0.1%"
        );
        maxSellAmount = newNum * (10 ** 18);
        emit UpdatedMaxSellAmount(maxSellAmount);
    }

    // remove limits after token is stable
    function removeLimits() external onlyOwner {
        limitsInEffect = false;
        emit RemovedLimits();
    }

    function _excludeFromMaxTransaction(
        address updAds,
        bool isExcluded
    ) private {
        _isExcludedMaxTransactionAmount[updAds] = isExcluded;
        emit MaxTransactionExclusion(updAds, isExcluded);
    }

    function excludeFromMaxTransaction(
        address updAds,
        bool isEx
    ) external onlyOwner {
        if (!isEx) {
            require(
                updAds != uniswapV2Pair,
                "Cannot remove uniswap pair from max txn"
            );
        }
        _isExcludedMaxTransactionAmount[updAds] = isEx;
    }

    function updateMaxWalletAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 3) / 1000) / 1e18,
            "Cannot set max wallet amount lower than 0.3%"
        );
        maxWalletAmount = newNum * (10 ** 18);
        emit UpdatedMaxWalletAmount(maxWalletAmount);
    }

    // change the minimum amount of tokens to sell from fees
    function updateSwapTokensAtAmount(uint256 newAmount) external onlyOwner {
        require(
            newAmount >= (totalSupply() * 1) / 100000,
            "Swap amount cannot be lower than 0.001% total supply."
        );
        require(
            newAmount <= (totalSupply() * 1) / 1000,
            "Swap amount cannot be higher than 0.1% total supply."
        );
        swapTokensAtAmount = newAmount;
    }

    function updateBuyFees(
        uint256 _treasuryFee,
        uint256 _liquidityFee
    ) external onlyOwner {
        buyTreasuryFee = _treasuryFee;
        buyLiquidityFee = _liquidityFee;
        buyTotalFees = buyTreasuryFee + buyLiquidityFee;
        require(buyTotalFees <= 15, "Must keep fees at 15% or less");
    }

    function updateSellFees(
        uint256 _treasuryFee,
        uint256 _liquidityFee
    ) external onlyOwner {
        sellTreasuryFee = _treasuryFee;
        sellLiquidityFee = _liquidityFee;
        sellTotalFees = sellTreasuryFee + sellLiquidityFee;
        require(sellTotalFees <= 30, "Must keep fees at 30% or less");
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    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");
        require(amount > 0, "amount must be greater than 0");

        if (limitsInEffect) {
            if (
                from != owner() &&
                to != owner() &&
                to != address(0) &&
                to != address(0xdead)
            ) {
                if (!tradingActive) {
                    require(
                        _isExcludedMaxTransactionAmount[from] ||
                            _isExcludedMaxTransactionAmount[to],
                        "Trading is not active."
                    );
                    require(from == owner(), "Trading is enabled");
                }

                //when buy
                if (
                    automatedMarketMakerPairs[from] &&
                    !_isExcludedMaxTransactionAmount[to]
                ) {
                    require(
                        amount <= maxBuyAmount,
                        "Buy transfer amount exceeds the max buy."
                    );
                    require(
                        amount + balanceOf(to) <= maxWalletAmount,
                        "Cannot Exceed max wallet"
                    );
                }
                //when sell
                else if (
                    automatedMarketMakerPairs[to] &&
                    !_isExcludedMaxTransactionAmount[from]
                ) {
                    require(
                        amount <= maxSellAmount,
                        "Sell transfer amount exceeds the max sell."
                    );
                } else if (
                    !_isExcludedMaxTransactionAmount[to] &&
                    !_isExcludedMaxTransactionAmount[from]
                ) {
                    require(
                        amount + balanceOf(to) <= maxWalletAmount,
                        "Cannot Exceed max wallet"
                    );
                }
            }
        }

        uint256 contractTokenBalance = balanceOf(address(this));

        bool canSwap = contractTokenBalance >= swapTokensAtAmount;

        if (
            canSwap &&
            swapEnabled &&
            !swapping &&
            !automatedMarketMakerPairs[from] &&
            !_isExcludedFromFees[from] &&
            !_isExcludedFromFees[to]
        ) {
            swapping = true;
            swapBack();
            swapping = false;
        }

        bool takeFee = true;
        // 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 Trades, not on wallet transfers

        if (takeFee) {
            // on sell
            if (automatedMarketMakerPairs[to] && sellTotalFees > 0) {
                fees = (amount * sellTotalFees) / 100;
                tokensForLiquidity += (fees * sellLiquidityFee) / sellTotalFees;
                tokensForTreasury += (fees * sellTreasuryFee) / sellTotalFees;
            }
            // on buy
            else if (automatedMarketMakerPairs[from] && buyTotalFees > 0) {
                fees = (amount * buyTotalFees) / 100;
                tokensForLiquidity += (fees * buyLiquidityFee) / buyTotalFees;
                tokensForTreasury += (fees * buyTreasuryFee) / buyTotalFees;
            }

            if (fees > 0) {
                super._transfer(from, address(this), fees);
            }

            amount -= fees;
        }

        super._transfer(from, to, amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();

        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    function setAutomatedMarketMakerPair(
        address pair,
        bool value
    ) external onlyOwner {
        require(
            pair != uniswapV2Pair,
            "The pair cannot be removed from automatedMarketMakerPairs"
        );

        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        automatedMarketMakerPairs[pair] = value;

        _excludeFromMaxTransaction(pair, value);

        emit SetAutomatedMarketMakerPair(pair, value);
    }

    // once enabled, can never be turned off
    function enableTrading(bool _status) external onlyOwner {
        require(!tradingActive, "Cannot re enable trading");
        tradingActive = _status;
        swapEnabled = true;
        emit EnabledTrading(tradingActive);
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // add the liquidity
        uniswapV2Router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            address(owner()),
            block.timestamp
        );
    }

    function setTreasuryAddress(address _TreasuryAddress) external onlyOwner {
        require(
            _TreasuryAddress != address(0),
            "_TreasuryAddress address cannot be 0"
        );
        TreasuryAddress = payable(_TreasuryAddress);
        emit UpdatedTreasuryAddress(_TreasuryAddress);
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        uint256 totalTokensToSwap = tokensForLiquidity + tokensForTreasury;

        if (contractBalance == 0 || totalTokensToSwap == 0) {
            return;
        }

        if (contractBalance > swapTokensAtAmount * 10) {
            contractBalance = swapTokensAtAmount * 10;
        }

        bool success;

        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = (contractBalance * tokensForLiquidity) /
            totalTokensToSwap /
            2;

        swapTokensForEth(contractBalance - liquidityTokens);

        uint256 ethBalance = address(this).balance;
        uint256 ethForLiquidity = ethBalance;

        uint256 ethForTreasury = (ethBalance * tokensForTreasury) /
            (totalTokensToSwap - (tokensForLiquidity / 2));

        ethForLiquidity -= ethForTreasury;

        tokensForLiquidity = 0;
        tokensForTreasury = 0;

        if (liquidityTokens > 0 && ethForLiquidity > 0) {
            addLiquidity(liquidityTokens, ethForLiquidity);
        }

        (success, ) = address(TreasuryAddress).call{
            value: address(this).balance
        }("");
    }

    function claimStuckTokens(address _token) external onlyOwner {
        if (_token == address(0x0)) {
            payable(owner()).transfer(address(this).balance);
            return;
        }
        IERC20 erc20token = IERC20(_token);
        uint256 balance = erc20token.balanceOf(address(this));
        erc20token.transfer(owner(), balance);
    }
}