import { Card, Suit } from "./Card";
import { shuffle } from "lodash";

export class Deck {

    private cards: Card[] = [];

    // Support multiple decks
    constructor(private numDecks = 1) {
        this.reset();
    }

    shuffle(): void {
        this.cards = shuffle(this.cards); // Just use lodash
    }

    drawCard(): Card {
        if (this.cards.length == 0) {
            throw new Error("Tried to draw card from empty deck");
        }
 
        return this.cards.shift() as Card; // Guaranteed to return a Card since we throw an Error if array is empty
    }

    // Draws a card, resetting the deck beforehands if the Deck is empty
    safeDrawCard(): Card {
        if (this.cards.length === 0) {
            this.reset();
        }

        return this.drawCard();
    }

    // Reset the deck back to the original 52 cards and shuffle it
    reset(): void {
        this.cards = [];

        for (let i = 1; i <= 13; ++i) {
            for (let j = 0; j < this.numDecks; ++j) {
                this.cards.push(new Card(i, Suit.Clubs));
                this.cards.push(new Card(i, Suit.Diamonds));
                this.cards.push(new Card(i, Suit.Hearts));
                this.cards.push(new Card(i, Suit.Spades));
            }
        }

        this.shuffle();
    }

    size(): number {
        return this.cards.length;
    }

    isEmpty(): boolean {
        return this.cards.length === 0;
    }

}