Minion

Call Me Anytime! Wait... Can You Even Call Me?

// ref. https://ciphershastra.com/minion.html
pragma solidity ^0.8.11;

contract Minion {
    mapping(address => uint256) private contributionAmount;
    mapping(address => bool) private pwned;

    address public owner;
    uint256 private constant MINIMUM_CONTRIBUTION = (1 gwei)/10;
    uint256 private constant MAXIMUM_CONTRIBUTION = (1 gwei)/5;

    constructor(address _player) {
        owner = _player;
    }

    function isContract(address account) internal view returns(bool) {
        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    function pwn() external payable {
        require(tx.origin != msg.sender, "Well we are not allowing EOAs, sorry");
        require(!isContract(msg.sender), "Well we don't allow Contracts either");
        require(msg.value >= MINIMUM_CONTRIBUTION, "Minimum Contribution needed is 0.1 gwei");
        require(msg.value <= MAXIMUM_CONTRIBUTION, "How did you get so much money? Max allowed is 0.2 gwei");
        require(block.timestamp % 120 >= 0 && block.timestamp % 120 < 60, "Not the right time");

        contributionAmount[owner] += msg.value;
        if (contributionAmount[owner] >= 1 gwei) {
            pwned[owner] = true;
        }
    }

    function verify(address account) external view returns(bool) {
        require(account != address(0), "You trynna trick me?");
        return pwned[account];
    }

    function retrieve() external {
        require(msg.sender == owner, "Are you the owner?");
        require(address(this).balance > 0, "No balance, you greedy hooman");
        payable(owner).transfer(address(this).balance);
    }

    function timeVal() external view returns(uint256){
        return block.timestamp;
    }
}