ERC20Basic.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import 'hardhat/console.sol';

interface IERC20 {

    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);

    function transfer(address recipient, uint256 amount) external returns (bool);
    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);
}


contract ERC20Basic is IERC20 {

    string public name;
    string public symbol; 
    uint8 public decimals;
    address immutable deployer;

    mapping(address => uint256) balances;
    mapping(address => mapping (address => uint256)) allowed;

    uint256 totalSupply_;

    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals,
        address _deployer
    ) {
        balances[msg.sender] = totalSupply_;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        deployer = _deployer;
    }

    function totalSupply() public override view returns (uint256) {
        return totalSupply_;
    }

    function balanceOf(address tokenOwner) public override view returns (uint256) {
        return balances[tokenOwner];
    }

    function transfer(address receiver, uint256 numTokens) public override returns (bool) {
        require(numTokens <= balances[msg.sender]);
        balances[msg.sender] = balances[msg.sender]-numTokens;
        balances[receiver] = balances[receiver]+numTokens;
        emit Transfer(msg.sender, receiver, numTokens);
        return true;
    }

    function approve(address delegate, uint256 numTokens) public override returns (bool) {
        allowed[msg.sender][delegate] = numTokens;
        emit Approval(msg.sender, delegate, numTokens);
        return true;
    }

    function allowance(address owner, address delegate) public override view returns (uint) {
        return allowed[owner][delegate];
    }

    function transferFrom(address owner, address buyer, uint256 numTokens) public override returns (bool) {
        require(numTokens <= balances[owner], 'Owner of tokens does not have sufficient token balance');
        require(numTokens <= allowed[owner][msg.sender], 'Owner of tokens has not approved sender specified token amount to transfer');

        balances[owner] = balances[owner]-numTokens;
        allowed[owner][msg.sender] = allowed[owner][msg.sender]-numTokens;
        balances[buyer] = balances[buyer]+numTokens;
        emit Transfer(owner, buyer, numTokens);
        return true;
    }

    function mint(address account, uint256 amount) public {
        require(msg.sender == deployer, "Only deployer can mint tokens");
        totalSupply_ += amount;
        balances[account] += amount;
    }
}