const choices = ["rock", "paper", "scissors"];

function getComputerChoice() {
    return choices[Math.floor(Math.random() * 3)];
}

function playRound(playerChoice, computerChoice) {
    let playerChoiceCapital = playerChoice.slice(0,1).toUpperCase() + playerChoice.slice(1,playerChoice.length)
    let computerChoiceCapital = computerChoice.slice(0,1).toUpperCase() + computerChoice.slice(1,computerChoice.length)

    if (playerChoice == computerChoice) {
        return {string: `It's a tie! ${playerChoiceCapital} vs ${computerChoiceCapital}.`,
                points: {player: true, computer: true}};
    } else if ((playerChoice == "rock" && computerChoice == "paper")
            || (playerChoice == "paper" && computerChoice == "scissors")
            || (playerChoice == "scissors" && computerChoice == "rock")) {
        return {string: `You lost! ${computerChoiceCapital} beats ${playerChoiceCapital}.`,
                points: {player: false, computer: true}};
    } else if ((playerChoice == "rock" && computerChoice == "scissors")
            || (playerChoice == "paper" && computerChoice == "rock")
            || (playerChoice == "scissors" && computerChoice == "paper")) {
        return {string: `You won! ${playerChoiceCapital} beats ${computerChoiceCapital}.`,
                points: {player: true, computer: false}};
    }
}

function game() {
    let points = {
        player: 0,
        computer: 0,
    }

    for (let i = 0; i < 5; i++) {
        let correctOption = false
        let playerChoice;
        
        while (correctOption == false) {
            playerChoice = prompt("What do you choose, 'rock', 'paper' or 'scissors'?").toLowerCase().trim();
        
            choices.forEach(element => {
                if (playerChoice == element) {
                    correctOption = true
                    return;
                }
            })
        }
        
        let round = playRound(playerChoice, getComputerChoice());

        if (round.points.player) {
            points.player++;
        }
        if (round.points.computer) {
            points.computer++;
        }
        let pointsString = `Points: ${points.player}:${points.computer}\n`;
        alert(pointsString + round.string);
    }
}

game();