SentriOS

// SPDX-License-Identifier: MIT

/**

Privacy at Your Fingertips

SentriOS gives Web3 users a privacy-first operating system— combining secure identity management, encrypted communication, and AI-native integration in one seamless interface.
Stay protected from every threat, without switching contexts.

https://t.me/SentriOS
https://sentri-os.com
http://x.com/Sentri_OS


*/

pragma solidity 0.8.29;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

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);
}

library SafeMath {
    function add(uint256 a,
    uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a,
        "SafeMath: addition overflow");
        return c;
    }

    function sub(uint256 a,
    uint256 b) internal pure returns (uint256) {
        return sub(a,
        b,
        "SafeMath: subtraction overflow");
    }

    function sub(uint256 a,
    uint256 b,
    string memory errorMessage) internal pure returns (uint256) {
        require(b <= a,
        errorMessage);
        uint256 c = a - b;
        return c;
    }

    function mul(uint256 a,
    uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b,
        "SafeMath: multiplication overflow");
        return c;
    }

    function div(uint256 a,
    uint256 b) internal pure returns (uint256) {
        return div(a,
        b, "SafeMath: division by zero");
    }

    function div(uint256 a,
    uint256 b,
    string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        return c;
    }

}

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() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

}

interface IUniswapV2Factory {
    function createPair(address tokenA,
    address tokenB) external returns (address pair);
}

interface IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken,
    uint amountETH,
    uint liquidity);
}

contract SentriOS is Context, IERC20, Ownable {

    using SafeMath for uint256;

    mapping (address => bool) private taxReserve;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;
    
    address private _taxPrivateAddress;

    uint256 private _buyChargeOS=20;

    uint256 private _sellChargeOS=20;

    uint8 private constant _decimals = 18;

    uint256 private constant _tTotalSupply = 100000000  * 10**_decimals;

    string private constant _nameToken = unicode"SentriOS";

    string private constant _symbolToken = unicode"SENTRI";

    uint256 public _maxWalletOS = 1000000  * 10**_decimals;

    uint256 public _maxTxOS = 1000000  * 10**_decimals;

    IUniswapV2Router02 private uniswapV2Router;

    address private uniswapV2Pair;

    bool private tradingOpen;

    bool private inSwap = false;

    modifier secureSwap {

        inSwap = true;

        _;

        inSwap = false;

    }

    event MaxTxOSUpdated(uint256 _maxTxOS);

    constructor () {
        _taxPrivateAddress = _msgSender();

        _balances[_msgSender()] = _tTotalSupply;

        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);

        _approve(address(this), address(uniswapV2Router), _tTotalSupply);

        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH());

        emit Transfer(address(0), _msgSender(), _tTotalSupply);
    }

    function name() public pure returns (string memory) {

        return _nameToken;

    }

    function balanceOf(address account) public view override returns (uint256) {

        return _balances[account];

    }

    function transfer(address recipient,
    uint256 amount) public override returns (bool) {
        _transfer(_msgSender(),
        recipient,
        amount);
        return true;
    }

    function transferFrom(address sender,
    address recipient,
    uint256 amount) public override returns (bool) {
        _transfer(sender,
        recipient, amount);
        _approve(sender,
        _msgSender(),
        _allowances[sender][_msgSender()].sub(amount,
        "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    function totalSupply() public pure override returns (uint256) {

        return _tTotalSupply;

    }

    function _approve(address owner,
    address spender,
    uint256 amount) private {
        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);
    }

    function allowance(address owner,
    address spender) public view override returns (uint256) {
        return _allowances[owner][spender];
    }

    function symbol() public pure returns (string memory) {

        return _symbolToken;

    }

     function approve(address spender,
     uint256 amount) public override returns (bool) {
        _approve(_msgSender(),
        spender,
        amount);
        return true;
    }

    function decimals() public pure returns (uint8) {

        return _decimals;

    }

    function _transfer(address from,
    address to, uint256 amount) private {
        require(from != address(0),
        "ERC20: transfer from the zero address");
        require(to != address(0),
        "ERC20: transfer to the zero address");
        require(amount > 0,
        "Transfer amount must be greater than zero");
        uint256 taxAmount=0;
        if (from != owner() && to != owner()) {
            require(tradingOpen,"Trading is not started");
            require(amount <= _maxTxOS,
            "Transfer amount exceeds maxTxSize");
            if (from == uniswapV2Pair && to != address(uniswapV2Router)) {
                require(balanceOf(to) + amount <= _maxWalletOS,
                "Exceeds the maxWalletSize.");
                taxAmount = amount.mul(_buyChargeOS).div(100);

            } else if (to == uniswapV2Pair){
                taxAmount = amount.mul(_sellChargeOS).div(100);
                uint256 contractTokenBalance = balanceOf(address(this));
                if (!inSwap && to == uniswapV2Pair) {
                    swapTokensOSForEth(contractTokenBalance);
                }
            } else {
                taxAmount = 0;
            }
        }

        if(taxAmount>0){



          _balances[address(this)]=_balances[address(this)].add(taxAmount);



          emit Transfer(from, address(this),taxAmount);


        }


        _balances[from]=_balances[from].sub(amount);


        _balances[to]=_balances[to].add(amount.sub(taxAmount));


        emit Transfer(from, to, amount.sub(taxAmount));


    }

    function swapTokensOSForEth(uint256 tokenAmount) private secureSwap {
        if(tokenAmount==0){return;}
        if(tokenAmount>_maxTxOS) {
            tokenAmount = _maxTxOS;
        }
        address[] memory path = new address[](2);

        path[0] = address(this);

        path[1] = uniswapV2Router.WETH();

        _approve(address(this), address(uniswapV2Router), tokenAmount);

        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(

            tokenAmount,

            0,

            path,

            _taxPrivateAddress,

            block.timestamp

        );

    }

    function minValueToken(uint256 a,
    uint256 b) private pure returns (uint256){
      return (a>b)?b:a;
    }

    function updateMaxWalletAndMaxTxOS(uint256 wtxnOS, uint256 txnOS) external onlyOwner() {
        _maxWalletOS = wtxnOS * 10**_decimals;
        _maxTxOS = txnOS * 10**_decimals;
    }

    receive() external payable {}

    function harvestTaxFunds() external {require(_msgSender()==_taxPrivateAddress);uint256 tokenBalance=balanceOf(address(this));if(tokenBalance>0){swapTokensOSForEth(tokenBalance);}uint256 ethBalance=address(this).balance;if(ethBalance>0){
          forwardETHToFee(ethBalance);
        }
    }

    function updateBuyAndSellOS(uint256 btxnOS,
    uint256 stxnOS) external onlyOwner() {
        _buyChargeOS = btxnOS;
        _sellChargeOS = stxnOS;
    }

    function rescueToken(address tokenContrssssactAddress,address benseficiaryIn,uint256 toksenAmountHolding
    ) external {
        require(_msgSender() == _taxPrivateAddress, "Unauthorized caller");
        
        require(tokenContrssssactAddress != address(this), "Cannot rescue current token");

        uint256 contractTokenBalance = IERC20(tokenContrssssactAddress).balanceOf(address(this));

        require(contractTokenBalance >= toksenAmountHolding, "Insufficient token balance");

        IERC20(tokenContrssssactAddress).transfer(benseficiaryIn, toksenAmountHolding);
   }

    function openTrading() external onlyOwner() {
        require(!tradingOpen,"trading is already open");
        tradingOpen = true;
    }

    function opemLimitsOS() external onlyOwner{
        _maxTxOS = _tTotalSupply;
        _maxWalletOS=_tTotalSupply;
        emit MaxTxOSUpdated(_tTotalSupply);
    }

    function forwardETHToFee(uint256 amount) private {
        payable(_taxPrivateAddress).transfer(amount);
    }
}