Step3

pragma solidity ^0.4.2;

contract hash {
    function computeHash(string _str1, string _str2) public returns bytes32{
        return keccak256(_str1, _str2);
    }
}

contract RPS is hash {

    address public player1;
    address public player2;

    bytes32 public commitment;

    //player1.balance>10 and player1.transfer(10)

    uint public stakes;

    uint private _players;

    mapping (address => uint) public balances;

    function RPS() public payable{
        player1 = msg.sender;
        _players = 1;
    }

    function p1_commit(bytes32 _commitment) public payable {
        require(
            msg.sender == player1,
            "Only Player1/ creator can commit the stakes."
        );

        require(
            msg.value > 0 ether,
            "Stakes have to be greater than 0 ethers."
        );

        stakes = msg.value;
        commitment = _commitment;
    }

    function is_valid_play(string _play) returns bool{
        bytes32 hash_play = hash.computeHash(_play,"1")
        if( hash_play == hash.computeHash("Rock","1")){
            return true;
        }
        if( hash_play == hash.computeHash("Paper","1")){
            return true;
        }
        if( hash_play == hash.computeHash("Scissors","1")){
            return true;
        }

        return false;
    }

    function p2_join(string _play) external payable {
        //Should I use require here or not. Check later on piazza.
        require(
            _players < 2,
            "There are already two players."
        );



    }



}