feat(application): add StartGame command, handler and GameRepository …

src/Chess/Application/Command/StartGame/StartGameCommand.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Chess\Application\Command\StartGame;
+
+final class StartGameCommand
+{
+}

src/Chess/Application/Command/StartGame/StartGameHandler.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Chess\Application\Command\StartGame;
+
+use Chess\Domain\Model\Game;
+use Chess\Domain\Repository\GameRepositoryInterface;
+use Chess\Domain\Value\GameId;
+use Symfony\Component\Messenger\Attribute\AsMessageHandler;
+
+#[AsMessageHandler(bus: 'command.bus')]
+final class StartGameHandler
+{
+    public function __construct(
+        private readonly GameRepositoryInterface $repository,
+    ) {
+    }
+
+    public function __invoke(StartGameCommand $command): GameId
+    {
+        $game = Game::start();
+        $this->repository->save($game);
+
+        return $game->id();
+    }
+}

src/Chess/Domain/Repository/GameRepositoryInterface.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Chess\Domain\Repository;
+
+use Chess\Domain\Model\Game;
+use Chess\Domain\Value\GameId;
+
+interface GameRepositoryInterface
+{
+    public function save(Game $game): void;
+
+    public function findById(GameId $id): ?Game;
+}

tests/Chess/Application/Command/StartGame/StartGameHandlerTest.php

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+<?php
+
+declare(strict_types=1);
+
+namespace Chess\Tests\Application\Command\StartGame;
+
+use Chess\Application\Command\StartGame\StartGameCommand;
+use Chess\Application\Command\StartGame\StartGameHandler;
+use Chess\Domain\Model\Game;
+use Chess\Domain\Repository\GameRepositoryInterface;
+use Chess\Domain\Value\GameId;
+use PHPUnit\Framework\TestCase;
+
+final class StartGameHandlerTest extends TestCase
+{
+    public function testItCreatesAndSavesAGame(): void
+    {
+        $repository = new class implements GameRepositoryInterface {
+            public ?Game $savedGame = null;
+
+            public function save(Game $game): void
+            {
+                $this->savedGame = $game;
+            }
+
+            public function findById(GameId $id): ?Game
+            {
+                return null;
+            }
+        };
+
+        $handler = new StartGameHandler($repository);
+        $gameId = $handler(new StartGameCommand());
+
+        self::assertInstanceOf(GameId::class, $gameId);
+        self::assertNotNull($repository->savedGame);
+        self::assertSame($gameId->toString(), $repository->savedGame->id()->toString());
+    }
+}