feat: darkness gating for go/look/take/examine + HUD light

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Semesterprojekt/src/test/java/thb/jeanluc/adventure/command/impl/DarknessTest.java

@@ -0,0 +1,64 @@
+package thb.jeanluc.adventure.command.impl;
+
+import org.junit.jupiter.api.Test;
+import thb.jeanluc.adventure.game.GameContext;
+import thb.jeanluc.adventure.io.TestIO;
+import thb.jeanluc.adventure.model.Direction;
+import thb.jeanluc.adventure.model.Player;
+import thb.jeanluc.adventure.model.Room;
+import thb.jeanluc.adventure.model.item.SwitchableItem;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DarknessTest {
+    private SwitchableItem lamp(boolean on) {
+        return SwitchableItem.builder().id("lamp").name("Lamp").description("d")
+                .state(on).onText("on").offText("off").light(true).build();
+    }
+
+    @Test
+    void cannotEnterDarkRoomWithoutLight() {
+        Room hall = new Room("hall", "Hall", "d");
+        Room cave = new Room("cave", "Cave", "d");
+        cave.setDark(true);
+        hall.addExit(Direction.NORTH, cave);
+        Player p = new Player(hall, 0);
+        GameContext ctx = new GameContext(null, p, new TestIO());
+
+        new GoCommand().execute(ctx, List.of("north"));
+        assertThat(p.getCurrentRoom()).isEqualTo(hall);
+        assertThat(((TestIO) ctx.getIo()).allOutput()).containsIgnoringCase("pitch black");
+    }
+
+    @Test
+    void canEnterDarkRoomWithLitLamp() {
+        Room hall = new Room("hall", "Hall", "d");
+        Room cave = new Room("cave", "Cave", "d");
+        cave.setDark(true);
+        hall.addExit(Direction.NORTH, cave);
+        Player p = new Player(hall, 0);
+        p.addItem(lamp(true));
+        GameContext ctx = new GameContext(null, p, new TestIO());
+
+        new GoCommand().execute(ctx, List.of("north"));
+        assertThat(p.getCurrentRoom()).isEqualTo(cave);
+    }
+
+    @Test
+    void lookAndTakeAreBlockedInTheDark() {
+        Room cave = new Room("cave", "Cave", "d");
+        cave.setDark(true);
+        Player p = new Player(cave, 0);
+        TestIO io = new TestIO();
+        GameContext ctx = new GameContext(null, p, io);
+
+        new LookCommand().execute(ctx, List.of());
+        assertThat(io.allOutput()).containsIgnoringCase("pitch black");
+
+        io.outputs().clear();
+        new TakeCommand().execute(ctx, List.of("anything"));
+        assertThat(io.allOutput()).containsIgnoringCase("too dark");
+    }
+}