3_Keran.sol

// contracts/Keran.sol
// SPDX-License-Identifier: MIT

pragma solidity ^0.8.17;

interface IERC20 {
    function transfer(address to, uint256 amount) external view returns (bool);
    function balanceOf(address account) external view returns (uint256);
    event Transfer(address indexed from, address indexed to, uint256 value);
}

contract Keran {
    address payable owner;
    IERC20 public token;

    uint256 public withdrawalAmount = 50 * (10**10);
    uint256 public lockTime = 1 minutes;

    event Withdrawal(address indexed to, uint256 indexed amount);
    event Deposit(address indexed from, uint256 indexed amount);

    mapping(address => uint256) nextAccessTime;

    constructor(address tokenAddress) payable {
        token = IERC20(tokenAddress);
        owner = payable(msg.sender);
    }

    function requestTokens() public {
        require(msg.sender != address(0), "Request must not originate from a zero account");
        require(token.balanceOf(address(this)) >= withdrawalAmount, "Insuficient balance in faucet for withdrawal request.");
        require(block.timestamp >=nextAccessTime[msg.sender], "Insuficient time elapsed since last withdrawal - try again later.");
        
        nextAccessTime[msg.sender] = block.timestamp + lockTime;
        
        token.transfer(msg.sender, withdrawalAmount);
    }

    receive() external payable {
        emit Deposit(msg.sender, msg.value);
    }

function getBalance() external view returns (uint256) {
    return token.balanceOf(address(this));
}

function setWithdrawalAmount(uint256 amount) public onlyOwner {
    withdrawalAmount = amount * (10**10);
}

function setLockTime(uint256 amount) public onlyOwner {
    lockTime = amount * 1 minutes;
}

function withdrawal() external onlyOwner {
    emit Withdrawal (msg.sender, token.balanceOf(address(this)));
    token.transfer(msg.sender, token.balanceOf(address(this)));
}

modifier onlyOwner() {
    require(msg.sender == owner, "Only the contract owner can call this function");
    _;    
}

}