// SPDX-License-Identifier: MIT                                                                               
                                                    
pragma solidity 0.8.17;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

contract ERC20 is Context, IERC20, IERC20Metadata {
    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 ILpPair {
    function sync() external;
}

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 swapExactETHForTokensSupportingFeeOnTransferTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) external payable;
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(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);
    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 getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
}

interface IDexFactory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

contract TokenHandler is Ownable {
    function sendTokenToOwner(address token) external onlyOwner {
        if(IERC20(token).balanceOf(address(this)) > 0){
            IERC20(token).transfer(owner(), IERC20(token).balanceOf(address(this)));
        }
    }
}

contract CHUINU is ERC20, Ownable {

    uint256 public maxBuyAmount;
    uint256 public maxSellAmount;
    uint256 public maxWalletAmount;

    IDexRouter public immutable dexRouter;
    address public immutable lpPair;

    TokenHandler public immutable tokenHandler;

    bool private swapping;
    uint256 public swapTokensAtAmount;

    address public operationsAddress;
    address public marketingAddress;

    uint256 public tradingActiveBlock = 0; // 0 means trading is not active

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;
    
     // Anti-bot and anti-whale mappings and variables
    mapping(address => uint256) private _holderLastTransferTimestamp; // to hold last Transfers temporarily during launch
    bool public transferDelayEnabled = true;

    IERC20 public constant SHIBA = IERC20(0x95aD61b0a150d79219dCF64E1E6Cc01f0B64C4cE);  //Mainnet: 0x95aD61b0a150d79219dCF64E1E6Cc01f0B64C4cE

    uint256 public buyTotalFees;
    uint256 public buyOperationsFee;
    uint256 public buyMarketingFee;
    uint256 public buyLiquidityFee;

    uint256 public sellTotalFees;
    uint256 public sellOperationsFee;
    uint256 public sellMarketingFee;
    uint256 public sellLiquidityFee;

    uint256 public tokensForOperations;
    uint256 public tokensForMarketing;
    uint256 public tokensForLiquidity;

    bool public zeroTaxMode;
    
    /******************/

    // 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();
    event RemovedLimits();

    event ExcludeFromFees(address indexed account, bool isExcluded);

    event UpdatedMaxBuyAmount(uint256 newAmount);

    event UpdatedMaxSellAmount(uint256 newAmount);

    event UpdatedMaxWalletAmount(uint256 newAmount);

    event UpdatedOperationsAddress(address indexed newWallet);
    event UpdatedMarketingAddress(address indexed newWallet);

    event MaxTransactionExclusion(address _address, bool excluded);

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiquidity
    );

    event TransferForeignToken(address token, uint256 amount);

    constructor() ERC20("Chu Inu", "CHU") {
        
        address newOwner = msg.sender; // can leave alone if owner is deployer.
        
        IDexRouter _dexRouter = IDexRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);  //uniswap router

        _excludeFromMaxTransaction(address(_dexRouter), true);
        dexRouter = _dexRouter;
        
        lpPair = IDexFactory(_dexRouter.factory()).createPair(address(this), address(SHIBA));
        _setAutomatedMarketMakerPair(address(lpPair), true);

        tokenHandler = new TokenHandler();
 
        uint256 totalSupply = 1_000_000_000_000 * 1e18;
        
        maxBuyAmount = totalSupply * 2 / 100;
        maxSellAmount = totalSupply * 2 / 100;
        maxWalletAmount = totalSupply * 2 / 100;
        swapTokensAtAmount = totalSupply * 25 / 100000; // 0.025% swap amount

        buyOperationsFee = 14;
        buyMarketingFee = 14;
        buyLiquidityFee = 0;
        buyTotalFees = buyOperationsFee + buyMarketingFee + buyLiquidityFee;

        sellOperationsFee = 14;
        sellMarketingFee = 14;
        sellLiquidityFee = 0;
        sellTotalFees = sellOperationsFee + sellMarketingFee + sellLiquidityFee;
        zeroTaxMode = false;

        _excludeFromMaxTransaction(newOwner, true);
        _excludeFromMaxTransaction(address(this), true);
        _excludeFromMaxTransaction(address(0xdead), true);

        excludeFromFees(newOwner, true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);

        operationsAddress = address(0x8976469CA4dD4BFde5693D9467E204576CBdE5C7);
        marketingAddress = address(0xA657373f948605D77735fb536c132335A34A12a8);
        
        _createInitialSupply(newOwner, totalSupply);
        transferOwnership(newOwner);
    }

    receive() external payable {}

    // once enabled, can never be turned off
    function enableTrading() external onlyOwner {
        require(!tradingActive, "Cannot reenable trading");
        tradingActive = true;
        swapEnabled = true;
        tradingActiveBlock = block.number;
        emit EnabledTrading();
    }
    
    // remove limits after token is stable
    function removeLimits() external onlyOwner {
        limitsInEffect = false;
        transferDelayEnabled = false;
        emit RemovedLimits();
    }
    
   
    // disable Transfer delay - cannot be reenabled
    function disableTransferDelay() external onlyOwner {
        transferDelayEnabled = false;
    }
    
    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);
    }

    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 _excludeFromMaxTransaction(address updAds, bool isExcluded) private {
        _isExcludedMaxTransactionAmount[updAds] = isExcluded;
        emit MaxTransactionExclusion(updAds, isExcluded);
    }

    function airdrop(address[] memory wallets, uint256[] memory amountsInTokens) external onlyOwner {
        require(wallets.length == amountsInTokens.length, "arrays must be the same length");
        require(wallets.length < 200, "Can only airdrop 200 wallets per txn due to gas limits");
        for(uint256 i = 0; i < wallets.length; i++){
            address wallet = wallets[i];
            uint256 amount = amountsInTokens[i]*1e18;
            _transfer(msg.sender, wallet, amount);
        }
    }
    
    function excludeFromMaxTransaction(address updAds, bool isEx) external onlyOwner {
        if(!isEx){
            require(updAds != lpPair, "Cannot remove uniswap pair from max txn");
        }
        _isExcludedMaxTransactionAmount[updAds] = isEx;
    }

    function setAutomatedMarketMakerPair(address pair, bool value) external onlyOwner {
        require(pair != lpPair, "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);
    }

    function updateBuyFees(uint256 _operationsFee, uint256 _marketingFee, uint256 _liquidityFee) external onlyOwner {
        buyOperationsFee = _operationsFee;
        buyMarketingFee = _marketingFee;
        buyLiquidityFee = _liquidityFee;
        buyTotalFees = buyOperationsFee + buyMarketingFee + buyLiquidityFee;
    }

    function updateSellFees(uint256 _operationsFee, uint256 _marketingFee, uint256 _liquidityFee) external onlyOwner {
        sellOperationsFee = _operationsFee;
        sellMarketingFee = _marketingFee;
        sellLiquidityFee = _liquidityFee;
        sellTotalFees = sellOperationsFee + sellMarketingFee + sellLiquidityFee;
    }

    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.");
                }
                
                // at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.  
                if (transferDelayEnabled){
                    if (to != address(dexRouter) && to != address(lpPair)){
                        require(_holderLastTransferTimestamp[tx.origin] < block.number - 4 && _holderLastTransferTimestamp[to] < block.number - 4, "_transfer:: Transfer Delay enabled.  Try again later.");
                        _holderLastTransferTimestamp[tx.origin] = block.number;
                        _holderLastTransferTimestamp[to] = block.number;
                    }
                }
                 
                //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;
        uint256 penaltyAmount = 0;
        // only take fees on buys/sells, do not take on wallet transfers
        if(takeFee && !zeroTaxMode){
            // on sell
            if (automatedMarketMakerPairs[to] && sellTotalFees > 0){
                fees = amount * sellTotalFees /100;
                tokensForLiquidity += fees * sellLiquidityFee / sellTotalFees;
                tokensForOperations += fees * sellOperationsFee / sellTotalFees;
                tokensForMarketing += fees * sellMarketingFee / sellTotalFees;
            }
            // on buy
            else if(automatedMarketMakerPairs[from] && buyTotalFees > 0) {
        	    fees = amount * buyTotalFees / 100;
        	    tokensForLiquidity += fees * buyLiquidityFee / buyTotalFees;
                tokensForOperations += fees * buyOperationsFee / buyTotalFees;
                tokensForMarketing += fees * buyMarketingFee / buyTotalFees;
            }
            
            if(fees > 0){    
                super._transfer(from, address(this), fees);
            }
        	
        	amount -= fees + penaltyAmount;
        }

        super._transfer(from, to, amount);
    }
    
    function addLiquidity(uint256 tokenAmount, uint256 shibaAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(dexRouter), tokenAmount);
        SHIBA.approve(address(dexRouter), shibaAmount);

        // add the liquidity
        dexRouter.addLiquidity(address(this), address(SHIBA), tokenAmount, shibaAmount, 0,  0,  address(this), block.timestamp);
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        uint256 totalTokensToSwap = tokensForLiquidity + tokensForOperations + tokensForMarketing;
        
        if(contractBalance == 0 || totalTokensToSwap == 0) {return;}

        if(contractBalance > swapTokensAtAmount * 10){
            contractBalance = swapTokensAtAmount * 10;
        }
        
        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = contractBalance * tokensForLiquidity / totalTokensToSwap / 2;
        
        swapTokensForSHIBA(contractBalance - liquidityTokens); 

        tokenHandler.sendTokenToOwner(address(SHIBA));
        
        uint256 shibaBalance = SHIBA.balanceOf(address(this));
        uint256 shibaForLiquidity = shibaBalance;

        uint256 shibaForOperations = shibaBalance * tokensForOperations / (totalTokensToSwap - (tokensForLiquidity/2));
        uint256 shibaForMarketing = shibaBalance * tokensForMarketing / (totalTokensToSwap - (tokensForLiquidity/2));

        shibaForLiquidity -= shibaForOperations + shibaForMarketing;
            
        tokensForLiquidity = 0;
        tokensForOperations = 0;
        tokensForMarketing = 0;
        
        if(liquidityTokens > 0 && shibaForLiquidity > 0){
            addLiquidity(liquidityTokens, shibaForLiquidity);
        }


        if(shibaForMarketing > 0){
            SHIBA.transfer(marketingAddress, shibaForMarketing);
        }

        if(SHIBA.balanceOf(address(this)) > 0){
            SHIBA.transfer(operationsAddress, SHIBA.balanceOf(address(this)));
        }
    }

    function swapTokensForSHIBA(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = address(SHIBA);
        _approve(address(this), address(dexRouter), tokenAmount);

        // make the swap
        dexRouter.swapExactTokensForTokensSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(tokenHandler),
            block.timestamp
        );
    }

  function withdrawStuckForeignTokens(address _token, address _to) external onlyOwner returns (bool _sent) {
        require(_token != address(0), "_token address cannot be 0");
        require(_token != address(this), "Can't withdraw native tokens");
        uint256 _contractBalance = IERC20(_token).balanceOf(address(this));
        _sent = IERC20(_token).transfer(_to, _contractBalance);
        emit TransferForeignToken(_token, _contractBalance);
    }

    // withdraw ETH if stuck or someone sends to the address
    function withdrawStuckETH() external onlyOwner {
        bool success;
        (success,) = address(msg.sender).call{value: address(this).balance}("");
    }

    function setOperationsAddress(address _operationsAddress) external onlyOwner {
        require(_operationsAddress != address(0), "_operationsAddress address cannot be 0");
        operationsAddress = payable(_operationsAddress);
        emit UpdatedOperationsAddress(_operationsAddress);
    }

     function setMarketingAddress(address _marketingAddress) external onlyOwner {
        require(_marketingAddress != address(0), "_marketingAddress address cannot be 0");
        marketingAddress = payable(_marketingAddress);
        emit UpdatedMarketingAddress(_marketingAddress);
    }

     function setZeroTaxMode(bool _zeroTaxMode) external onlyOwner {
        zeroTaxMode = _zeroTaxMode;
    }

}