From 45c53304cf5ed7ac7893b95f2db676b6f0f0c3ad Mon Sep 17 00:00:00 2001
From: Divyansh Seth <divyanshseth08@gmail.com>
Date: Sun, 2 Jun 2024 00:57:51 +0530
Subject: [PATCH] engine: improved card drawing logic. this commit handles the
drawing logic from an empty cardDeck. - It reshuffles the thrown cards into
the card deck when the card deck is empty and a player needs to draw a card.
- It returns success message if the card is drawn successfully else returns
message error. - Also added relevant unit test, in engine.test.ts, to verify
this function (drawCardFromDeck) works correctly.
---
backend/tests/engine.test.ts | 21 ++++++++++++++++++
backend/uno-game-engine/engine.ts | 36 +++++++++++++++++++++++++------
2 files changed, 51 insertions(+), 6 deletions(-)
create mode 100644 backend/tests/engine.test.ts
diff --git a/backend/tests/engine.test.ts b/backend/tests/engine.test.ts
new file mode 100644
index 0000000..1fd7312
--- /dev/null
+++ b/backend/tests/engine.test.ts
@@ -0,0 +1,21 @@
+import { GameEngine } from '../uno-game-engine/engine';
+
+describe('testing drawCardFromDeck()', () => {
+ test('draws a card when deck is empty but thrownCards is not', () => {
+ const game = new GameEngine();
+ game.addPlayer({ id: '1', cards: [] });
+ game.cardDeck = [];
+ game.thrownCards = [
+ {
+ type: 'number',
+ color: 'yellow',
+ value: '1',
+ id: 'card-number-yellow-1-1',
+ },
+ ];
+ const player = game.players[0];
+ const status: EventResult = game.drawCardFromDeck(player);
+ expect(player.cards.length).toBe(1);
+ expect(status.type).toBe('SUCCESS');
+ });
+});
diff --git a/backend/uno-game-engine/engine.ts b/backend/uno-game-engine/engine.ts
index 17bf2fe..0c97d04 100644
--- a/backend/uno-game-engine/engine.ts
+++ b/backend/uno-game-engine/engine.ts
@@ -1,4 +1,4 @@
-import { getShuffledCardDeck } from './deck';
+import { getShuffledCardDeck, shuffle } from './deck';
import { handleEvent } from './gameEvents';
const NUM_CARDS_PER_PLAYER = 7;
@@ -47,11 +47,35 @@ export class GameEngine {
this.currentPlayerIndex =
(this.currentPlayerIndex + this.direction) % this.players.length;
}
- drawCardFromDeck(player: Player) {
- //todo: Handle the case when the deck is empty and we have to move the thrown cards back to the deck
- this.players
- .find((p: Player) => p.id === player.id)
- .cards.push(this.cardDeck.pop());
+ drawCardFromDeck(player: Player): EventResult {
+ try {
+ if (this.cardDeck.length === 0) {
+ this.cardDeck = [...this.thrownCards];
+ this.thrownCards = [];
+ shuffle(this.cardDeck);
+ }
+ const currentPlayer = this.players.find(
+ (p: Player) => p.id === player.id
+ );
+ if (currentPlayer && this.cardDeck) {
+ const card = this.cardDeck.pop();
+ if (card) {
+ currentPlayer.cards.push(card);
+ return {
+ type: 'SUCCESS',
+ message: 'Card drawn successfully',
+ };
+ } else
+ return { type: 'ERROR', message: 'Unable to draw a card' };
+ } else {
+ return {
+ type: 'ERROR',
+ message: 'Player not found or cardDeck is empty',
+ };
+ }
+ } catch (error) {
+ return { type: 'ERROR', message: (error as Error).message };
+ }
}
dispatchEvent(event: GameEvent) {
// handle different types of events based on event.type