feat(save): SaveService disk persistence (atomic write, list, load)

Semesterprojekt/src/test/java/thb/jeanluc/adventure/save/SaveServiceTest.java

@@ -0,0 +1,63 @@
+package thb.jeanluc.adventure.save;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+import thb.jeanluc.adventure.game.GameSession;
+import thb.jeanluc.adventure.loader.WorldLoader;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class SaveServiceTest {
+
+    private GameSession freshSession(String slot) {
+        WorldLoader.LoadResult r = new WorldLoader().load();
+        return new GameSession(r.world(), r.player(), slot);
+    }
+
+    @Test
+    void saveThenLoadReproducesState(@TempDir Path dir) {
+        SaveService svc = new SaveService(dir);
+        GameSession s = freshSession("my-game");
+        s.getState().set("power_on");
+        s.getPlayer().setGold(4);
+        s.setTurn(9);
+        svc.save(s);
+
+        GameSession loaded = svc.load("my-game");
+        assertThat(loaded.getState().isSet("power_on")).isTrue();
+        assertThat(loaded.getPlayer().getGold()).isEqualTo(4);
+        assertThat(loaded.getTurn()).isEqualTo(9);
+        assertThat(loaded.getSlotName()).isEqualTo("my-game");
+    }
+
+    @Test
+    void listReturnsSlotMetadata(@TempDir Path dir) {
+        SaveService svc = new SaveService(dir);
+        GameSession s = freshSession("Alpha Run");
+        s.setTurn(3);
+        svc.save(s);
+
+        List<SaveSlotInfo> slots = svc.list();
+        assertThat(slots).hasSize(1);
+        assertThat(slots.getFirst().slotName()).isEqualTo("Alpha Run");
+        assertThat(slots.getFirst().turn()).isEqualTo(3);
+    }
+
+    @Test
+    void listSkipsCorruptFiles(@TempDir Path dir) throws Exception {
+        Files.writeString(dir.resolve("broken.json"), "{ not json");
+        assertThat(new SaveService(dir).list()).isEmpty();
+    }
+
+    @Test
+    void loadCorruptFileThrowsSaveException(@TempDir Path dir) throws Exception {
+        Files.writeString(dir.resolve("bad.json"), "{ not json");
+        SaveService svc = new SaveService(dir);
+        assertThrows(SaveException.class, () -> svc.load("bad"));
+    }
+}