feat: conditional NPC dialogue

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

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

@@ -0,0 +1,37 @@
+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.Condition;
+import thb.jeanluc.adventure.model.DialogueLine;
+import thb.jeanluc.adventure.model.Npc;
+import thb.jeanluc.adventure.model.Player;
+import thb.jeanluc.adventure.model.Room;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DialogueTest {
+    @Test
+    void dialogueSwitchesWithFlagElseGreeting() {
+        Room room = new Room("k", "K", "d");
+        Npc man = Npc.shell("man", "Old Man", "stooped", "Hello there.");
+        man.addDialogue(new DialogueLine(
+                List.of(new Condition(Condition.Type.FLAG, "power_on")),
+                "The lights are back, bless you!"));
+        room.addNpc(man);
+        Player player = new Player(room, 0);
+        TestIO io = new TestIO();
+        GameContext ctx = new GameContext(null, player, io);
+
+        new TalkCommand().execute(ctx, List.of("man"));
+        assertThat(io.allOutput()).contains("Hello there");
+
+        io.outputs().clear();
+        ctx.getState().set("power_on");
+        new TalkCommand().execute(ctx, List.of("man"));
+        assertThat(io.allOutput()).contains("lights are back").doesNotContain("Hello there");
+    }
+}