Javascript Dealer class for card games.

dealer.js

var Dealer = function (decks, suits, cards) {

    var pack = [],	// cards yet to be dealt (stock/shoe)
        played = 0,	// cards already dealt,
        suitsLen,
        cardsLen,
        i,
        j,
        
        // Fisher-Yates shuffle - http://jsfromhell.com/array/shuffle
        shuffle = function () { 
             for(var j, x, p = pack, i = p.length; i; j = ~~(Math.random() * i), x = p[--i], p[i] = p[j], p[j] = x);
        };

    // pack defaults
    decks = decks || 1;
    suits = suits || ['♥', '♣', '♦', '♠'];
    cards = cards || ['A', 2, 3, 4, 5, 6, 7, 8, 9, 10, 'J', 'Q', 'K'];

    suitsLen = j = suits.length;
    cardsLen = cards.length;

    // generate single deck
    while (j--) {
        for (i = 0; i < cardsLen; i++) {
            pack.push(suits[j] + cards[i]);
        }
    }

    // put the right number of decks in the pack
    while (--decks) {
        pack = pack.concat(pack.slice(0, suitsLen * cardsLen));
    }

    // shuffle the new pack
    shuffle();

    return {

        // deals from the top of the deck, defaults to 1 card
        deal: function (num) {
            num = num || 1;
            played += num;
            return pack.slice(played - num, played);
        },

        // put the played cards back in the deck and reshuffle
        resetDeck: function () {
            played = 0;
            shuffle();
        }
    };
};