NASA ON BASE

/**
 NASA ON BASE - $NASA
 JoiN oUr moOOOOOOoooOooon tRiiiiiiiiiiiiiiiiiiiiP 🚀
*/

/**
Twitter  https://x.com/NASAONBASE
Telegram https://t.me/+Xf_StTwJTkNlZDU0
Website  https://nasaonbase.online/
*/

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract NASA {
    string public name = "NASA ON BASE";
    string public symbol = "NASA";
    uint8 public decimals = 18;
    uint256 public totalSupply;
    address public owner;
    uint256 public taxRate = 0; // 0% tax
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;
    mapping(address => bool) private _isExcludedFromTax;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    event TaxRateChanged(uint256 newTaxRate);

    modifier onlyOwner() {
        require(msg.sender == owner, "Caller is not the owner");
        _;
    }

    constructor() {
        owner = msg.sender;
        totalSupply = 1000000000 * (10 ** uint256(decimals));
        balanceOf[owner] = totalSupply;
        _isExcludedFromTax[owner] = true;
        emit Transfer(address(0), owner, totalSupply);
    }

    function transfer(address to, uint256 value) public returns (bool success) {
        _transfer(msg.sender, to, value);
        return true;
    }

    function approve(address spender, uint256 value) public returns (bool success) {
        allowance[msg.sender][spender] = value;
        emit Approval(msg.sender, spender, value);
        return true;
    }

    function transferFrom(address from, address to, uint256 value) public returns (bool success) {
        require(value <= balanceOf[from], "Balance too low");
        require(value <= allowance[from][msg.sender], "Allowance too low");

        allowance[from][msg.sender] -= value;
        _transfer(from, to, value);
        return true;
    }

    function setTaxRate(uint256 newTaxRate) public onlyOwner {
        require(newTaxRate <= 100, "Tax rate must be less than or equal to 100%");
        taxRate = newTaxRate;
        emit TaxRateChanged(newTaxRate);
    }

    function excludeFromTax(address account, bool excluded) public onlyOwner {
        _isExcludedFromTax[account] = excluded;
    }

    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(owner, address(0));
        _isExcludedFromTax[owner] = false; // Remove tax exclusion when renouncing ownership
        owner = address(0);
    }

    function _transfer(address from, address to, uint256 value) internal {
        require(to != address(0), "Invalid address");
        require(value <= balanceOf[from], "Balance too low");

        uint256 taxAmount = 0;
        if (!_isExcludedFromTax[from] && !_isExcludedFromTax[to]) {
            taxAmount = value * taxRate / 100;
        }

        uint256 netAmount = value - taxAmount;
        balanceOf[from] -= value;
        balanceOf[to] += netAmount;
        if (taxAmount > 0) {
            balanceOf[address(this)] += taxAmount;
            emit Transfer(from, address(this), taxAmount);
        }
        emit Transfer(from, to, netAmount);
    }
}

{
  "compilationTarget": {
    "NASA.sol": "NASA"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}