var moves = {1 : "rock", 2 : "paper", 3 : "scissors"}

while (true) {
    var enemyDecision = moves[Math.ceil(Math.random() * 3)]
    var myDecision = prompt("Rock, paper, or scissors?").toLowerCase()
    var result = (
        myDecision == enemyDecision && "Tie!" ||
        (
            myDecision == "rock" && enemyDecision == "paper" ||
            myDecision == "paper" && enemyDecision == "scissors" ||
            myDecision == "scissors" && enemyDecision == "rock"
        ) && "You lose!" ||
        "You win!"
    )
    console.log(result + " You chose " + myDecision + " and your opponent chose " + enemyDecision)
}