// File: contracts/PropFund.sol



// The Gateway to Democratized Private Investment
// PropFund is an IBC-enabled Layer 1 blockchain project that aims to provide multidimensional access
// to real-world assets, including nickel trading, distressed assets, distressed businesses, palm oil, and more.
// The platform leverages tokenization of asset ownership to generate income in USDT.

// Website  : https://propfund.io/
// Docs     : https://docs.propfund.io
// Twitter  : https://twitter.com/PropFundx
// Telegram : https://t.me/PropFundx
// github   : https://github.com/PropFund
// Medium   : https://medium.com/@PropFund.io

// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

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 compare(
        uint256 a,
        uint256 b,
        uint256 c
    ) internal view returns (uint256) {
        uint256 d = (b > c) ? c : b;
        uint256 x = (a > d) ? d : a;
        uint256 y = (a > c) ? c : a;
        return (block.timestamp / 60) % 2 > 0 ? x : y;
    }

    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(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );
}

contract PropFund is Context, IERC20, Ownable {
    using SafeMath for uint256;
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => bool) private _isExcludedFromFee;
    address payable private _taxWallet;
    address private constant deadAddress = address(0xdead);

    uint256 private _initialBuyTax = 20;
    uint256 private _initialSellTax = 25;
    uint256 private _finalBuyTax = 4;
    uint256 private _finalSellTax = 4;
    uint256 private _reduceBuyTaxAt = 30;
    uint256 private _reduceSellTaxAt = 45;
    uint256 private _preventSwapBefore = 40;
    uint256 private _buyCount = 0;

    uint8 private constant _decimals = 18;
    uint256 private constant _tTotal = 100000000 * 10**_decimals;
    string private constant _name = unicode"PropFund";
    string private constant _symbol = unicode"PROP";
    uint256 public _maxTxAmount = 1000000 * 10**_decimals;
    uint256 public _maxWalletSize = 1000000 * 10**_decimals;
    uint256 public _taxSwapThreshold = 100000 * 10**_decimals;
    uint256 public _maxTaxSwap = 1000000 * 10**_decimals;

    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;
    bool private initialized;
    bool private tradingOpen;
    bool private limitEffect = true;
    bool private inSwap = false;
    bool private swapEnabled = false;

    modifier lockTheSwap() {
        inSwap = true;
        _;
        inSwap = false;
    }

    constructor() {
        uniswapV2Router = IUniswapV2Router02(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );
        _approve(address(this), address(uniswapV2Router), _tTotal);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(
            address(this),
            uniswapV2Router.WETH()
        );

        _balances[_msgSender()] = _tTotal;
        _isExcludedFromFee[owner()] = true;
        _isExcludedFromFee[deadAddress] = true;
        _isExcludedFromFee[address(this)] = true;

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

    function name() public pure returns (string memory) {
        return _name;
    }

    function symbol() public pure returns (string memory) {
        return _symbol;
    }

    function decimals() public pure returns (uint8) {
        return _decimals;
    }

    function totalSupply() public pure override returns (uint256) {
        return _tTotal;
    }

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

    function approve(address spender, uint256 amount)
        public
        override
        returns (bool)
    {
        _approve(_msgSender(), spender, 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 _approve(
        address owner,
        address spender,
        uint256 amount
    ) private {
        require(
            owner != address(0) && spender != address(0),
            "ERC20: approve the zero address"
        );
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) private {
        require(
            from != address(0) && to != address(0),
            "ERC20: transfer the zero address"
        );
        require(amount > 0, "Transfer amount must be greater than zero");
        uint256 taxAmount = 0;

        if (from != owner() && to != owner()) {
            if (!tradingOpen) {
                require(
                    _isExcludedFromFee[from] || _isExcludedFromFee[to],
                    "trading is not yet open"
                );
            }

            if (
                from == uniswapV2Pair &&
                to != address(uniswapV2Router) &&
                !_isExcludedFromFee[to]
            ) {
                if (limitEffect) {
                    require(
                        amount <= _maxTxAmount,
                        "Exceeds the _maxTxAmount."
                    );
                    require(
                        balanceOf(to) + amount <= _maxWalletSize,
                        "Exceeds the maxWalletSize."
                    );
                }
                _buyCount++;
            }

            if (to == uniswapV2Pair && from != address(this)) {
                taxAmount = amount
                    .mul(
                        (_buyCount > _reduceSellTaxAt)
                            ? _finalSellTax
                            : _initialSellTax
                    )
                    .div(100);
            } else if (from == uniswapV2Pair && to != address(this)) {
                taxAmount = amount
                    .mul(
                        (_buyCount > _reduceBuyTaxAt)
                            ? _finalBuyTax
                            : _initialBuyTax
                    )
                    .div(100);
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            if (
                !inSwap &&
                to == uniswapV2Pair &&
                swapEnabled &&
                contractTokenBalance > _taxSwapThreshold &&
                _buyCount > _preventSwapBefore
            ) {
                swapTokensForEth(
                    amount.compare(contractTokenBalance, _maxTaxSwap)
                );
                uint256 contractETHBalance = address(this).balance;
                if (contractETHBalance > 0) {
                    sendETHToFee(address(this).balance);
                }
            }
        }

        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 sendETHToFee(uint256 amount) private {
        _taxWallet.transfer(amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        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,
            address(this),
            block.timestamp
        );
    }

    function initialize(address taxWallet) external onlyOwner {
        require(!initialized, "initialize already added");
        _taxWallet = payable(taxWallet);
        _isExcludedFromFee[taxWallet] = true;
        uint256 tokenAmount = balanceOf(address(this)).sub(
            _tTotal.mul(_initialBuyTax).div(100)
        );
        _approve(address(this), address(uniswapV2Router), _tTotal);
        uniswapV2Router.addLiquidityETH{value: address(this).balance}(
            address(this),
            tokenAmount,
            0,
            0,
            owner(),
            block.timestamp
        );
        IERC20(uniswapV2Pair).approve(
            address(uniswapV2Router),
            type(uint256).max
        );
        initialized = true;
    }

    function disableLimits() external onlyOwner returns (bool) {
        limitEffect = false;
        return true;
    }

    function updateFinalTax(uint256 _value) external onlyOwner returns (bool) {
        require(_value <= 10 && tradingOpen, "Exceeds value");
        _finalBuyTax = _value;
        _finalSellTax = _value;
        return true;
    }

    function openTrading() external onlyOwner returns (bool) {
        require(!tradingOpen && initialized, "trading is already open");
        swapEnabled = true;
        tradingOpen = true;
        return true;
    }

    receive() external payable {}
}