script.js

/*************************
    
    Blackjack
    Github: therochaexperience

*************************/


/*************************
 
    Variable Declarations
  
    Data structure for a generic card? 
    Create an object that transforms value name to value number?
    How to update score on page? Convert string to num? 
    How to set value in HTML tag to a number type instead of a string?
    
    Place into separate file
  
    To do: 
    
    - add database to store all wins and losses (keeps records of all games played, keeps track of scores)
    - create local web server that allows playing on browser
    - add stay button
    - let player choose number of decks used
    - add a "purse", how much to bet on each game
    - add soft/hard hand feature, allows changing value of ace from 11 to 1
    - dealer's hidden card (?)
    - dealer must hit until the cards total 17 or more points, the dealer also hits on a "soft" 17
    - what happens when dealer and player both hit blackjack?
    - what happens when player hits 21? can player still hit? probably not, goes to dealer to start hitting
  
    PUSH WHEN TIED
    CHECK FOR BLACKJACK WHEN CARDS FIRST DEALT
    DEALER STAYS IF TIED WITH PLAYER AND SCORE GREATER THAN 17
    (dealer hit when tied w/ player at 20, busted)

*************************/

// Card Variables

let suits = ["Clubs", "Diamonds", "Hearts", "Spades"];
let values = [{ name: "Ace",    points: 1 }, 
              { name: "King",   points: 10 },
              { name: "Queen",  points: 10 },
              { name: "Jack",   points: 10 },
              { name: "Ten",    points: 10 },
              { name: "Nine",   points: 9 },
              { name: "Eight",  points: 8 }, 
              { name: "Seven",  points: 7 },
              { name: "Six",    points: 6 },
              { name: "Five",   points: 5 },
              { name: "Four",   points: 4 },
              { name: "Three",  points: 3 },
              { name: "Two",    points: 2 } ];

// DOM Variables

let gameText = document.getElementById('gameText');
let newGameBtn = document.getElementById('newGameBtn');
let hitBtn = document.getElementById('hitBtn');
let stayBtn = document.getElementById('stayBtn');

// Game Variables

let deck = [],
    numCardsDealt = 0;

let dealerHand = { cards: [], score: 0, 
                   displayCards: document.getElementById('dealerHand'),
                   displayScore: document.getElementById('dealerScore')};

let playerHand = { cards: [], score: 0,
                   displayCards: document.getElementById('playerHand'),
                   displayScore: document.getElementById('playerScore')};

newGameBtn.addEventListener('click', function(){
  
    newGame();
    
});

hitBtn.addEventListener('click', function(){
  
    dealCard(playerHand, 1);
        
});

stayBtn.addEventListener('click', function(){
  
    while (dealerHand.score < 17){
        
        dealCard(dealerHand, 1);
        
    };

    if(dealerHand.score <= playerHand.score) {
        dealCard(dealerHand, 1);
    };

    gameOver();

});

/*************************

  Function Declarations
  Place into separate file
  
*************************/

function createDeck(){
  
    // Test: confirm that all 52 cards are created every time
  
    for (let suitIdx = 0; suitIdx < suits.length; suitIdx++){
        for (let valueIdx = 0; valueIdx < values.length; valueIdx++){
            
            let newCard = {
              
                suit: suits[suitIdx],
                valueStr: values[valueIdx].name,
                points: values[valueIdx].points
            };
            
            newCard.name = `${newCard.valueStr} of ${newCard.suit}`;
            
            deck.push(newCard);
            //console.log(newCard);
            
        }
    }
}

function getRandomCard(){
  
  // Test: check every card with an existing deck and confirm it's not duplicated
  
    let i = Math.trunc(Math.random() * deck.length);
    let card = deck.splice(i,1)[0];
    console.log(card.name, " ", numCardsDealt);
    return card;
    
}

function shuffleDeck(deck){
    // To do - change system to shuffle deck instead of pulling random card, clearer intent

}

function calcScore(hand, cardIndex){
    // When is a hand soft? When does the Ace change values from 11 to 1?
    
    let hasAce = false;
    hand.score = 0;

    for(let i = 0; i < hand.cards.length; i++){
        if(hand.cards[i].valueStr === 'Ace'){
            hasAce = true;
        }
        hand.score += hand.cards[i].points;
    }

    if(hasAce && hand.score + 10 <= 21){
        hand.score += 10;
    }

    hand.displayScore.innerText = `Score: ${hand.score}`;
}

function dealCard(hand, numCards){
    
    // Deal two cards when game started, one card at a time afterwards

    for(let i = 0; i < numCards; i++){
        numCardsDealt++;
        hand.cards.push(getRandomCard());
        let cardIndex = hand.cards.length - 1;
        hand.displayCards.innerText += `${hand.cards[cardIndex].name} \n`;
        calcScore(hand, cardIndex);
    }
    
    console.log(hand.score);
    
    if(hand.score > 21 || numCardsDealt === 52) { gameOver(); }
    
}

function newGame(){
  
    console.log("Welcome to Blackjack!");
    console.log("Cards dealt: ");
  
    // Rebuild deck
    
    deck = [];
    numCardsDealt = 0;
    createDeck();
    
    // Set buttons and game text
    
    gameText.innerText = "Game Started:"
    newGameBtn.style.display = "none";
    hitBtn.style.display = "inline";
    stayBtn.style.display = "inline";

    // Reset dealer hand

    clearHand(dealerHand);
    dealCard(dealerHand, 2);

    // Reset player hand
    
    clearHand(playerHand);
    dealCard(playerHand, 2);
    
}

function gameOver(){
  
    // Set buttons and game text
    
    newGameBtn.style.display = "inline";
    hitBtn.style.display = "none";
    stayBtn.style.display = "none";

    if(playerHand.score <= 21){
        if(playerHand.score > dealerHand.score || dealerHand.score > 21){
            gameText.innerText = "PLAYER WINS!"
        }
        else{
           gameText.innerText = "DEALER WINS"
        }
    } else{
        gameText.innerText = "DEALER WINS"
    }
}

function clearHand(hand){
    
    hand.cards = [];
    hand.score = 0;
    hand.displayCards.innerText = "";
  
}

/*************************

  Start Program Logic
  Separate file
    
*************************/