fix(items): make scenery items fixed so they cannot be taken

Nothing stopped the player from picking up scenery. The front door is an
ordinary switchable item in the foyer whose on-transition sets the 'left_manor'
flag that every ending keys off, so it could be carried into the cellar and used
there to end the game two floors underground. The chapel shrine could likewise
be carried out and the locket/photograph ritual performed anywhere.

Item gains a 'fixed' flag; TakeCommand refuses fixed items and leaves them in
the room. Fixed items stay usable in place, so all recipes still work.

Marked fixed: front_door, shrine, generator, valve, portrait — their
descriptions already claimed they were bolted down.

Semesterprojekt/src/main/java/thb/jeanluc/adventure/command/impl/TakeCommand.java

@@ -27,13 +27,19 @@ public class TakeCommand implements Command {
         }
         String itemId = args.getFirst();
         Room room = ctx.getPlayer().getCurrentRoom();
-        Optional<Item> taken = room.removeItem(itemId);
+        Optional<Item> found = room.findItem(itemId);
-        if (taken.isEmpty()) {
+        if (found.isEmpty()) {
             ctx.getIo().write("There is no '" + itemId + "' here.");
             return;
         }
-        ctx.getPlayer().addItem(taken.get());
+        Item item = found.get();
-        ctx.getIo().write("You take the " + taken.get().getName() + ".");
+        if (item.isFixed()) {
+            ctx.getIo().write("The " + item.getName() + " is part of the room — you can't take it.");
+            return;
+        }
+        room.removeItem(itemId);
+        ctx.getPlayer().addItem(item);
+        ctx.getIo().write("You take the " + item.getName() + ".");
     }
 
     @Override

Semesterprojekt/src/main/java/thb/jeanluc/adventure/loader/ItemFactory.java

@@ -13,6 +13,7 @@ import thb.jeanluc.adventure.model.item.SwitchableItem;
  */
 public final class ItemFactory {
 
+    /** Utility class; not instantiable. */
     private ItemFactory() {
     }
 
@@ -31,6 +32,7 @@ public final class ItemFactory {
                     .name(dto.name())
                     .description(dto.description())
                     .light(Boolean.TRUE.equals(dto.light()))
+                    .fixed(Boolean.TRUE.equals(dto.fixed()))
                     .build();
             case "readable" -> ReadableItem.builder()
                     .id(dto.id())
@@ -38,6 +40,7 @@ public final class ItemFactory {
                     .description(dto.description())
                     .readText(dto.readText())
                     .light(Boolean.TRUE.equals(dto.light()))
+                    .fixed(Boolean.TRUE.equals(dto.fixed()))
                     .build();
             case "switchable" -> SwitchableItem.builder()
                     .id(dto.id())
@@ -48,6 +51,7 @@ public final class ItemFactory {
                     .offText(dto.offText())
                     .effects(thb.jeanluc.adventure.loader.dto.EffectDto.toModelList(dto.effects()))
                     .light(Boolean.TRUE.equals(dto.light()))
+                    .fixed(Boolean.TRUE.equals(dto.fixed()))
                     .build();
             default -> throw new WorldLoadException(
                     "Unknown item type '" + dto.type() + "' on item '" + dto.id() + "'");

Semesterprojekt/src/main/java/thb/jeanluc/adventure/loader/dto/ItemDto.java

@@ -16,6 +16,7 @@ import java.util.List;
  * @param offText      message printed when a switchable transitions to off
  * @param effects      effects applied when a switchable transitions to on; nullable
  * @param light        whether this item is a light source; nullable
+ * @param fixed        whether this item is scenery that cannot be taken; nullable
  */
 public record ItemDto(
         String type,
@@ -27,11 +28,24 @@ public record ItemDto(
         String onText,
         String offText,
         List<EffectDto> effects,
-        Boolean light
+        Boolean light,
+        Boolean fixed
 ) {
-    /** Backward-compatible constructor without effects/light. */
+    /**
+     * Backward-compatible constructor without effects/light/fixed, which default to null.
+     *
+     * @param type         discriminator: {@code plain | readable | switchable}
+     * @param id           unique slug
+     * @param name         display name
+     * @param description  examine description
+     * @param readText     text printed when a readable item is used
+     * @param initialState initial on/off state of a switchable item
+     * @param onText       message printed when a switchable transitions to on
+     * @param offText      message printed when a switchable transitions to off
+     */
     public ItemDto(String type, String id, String name, String description,
                    String readText, Boolean initialState, String onText, String offText) {
-        this(type, id, name, description, readText, initialState, onText, offText, null, null);
+        this(type, id, name, description, readText, initialState, onText, offText,
+                null, null, null);
     }
 }

Semesterprojekt/src/main/java/thb/jeanluc/adventure/model/item/Item.java

@@ -36,6 +36,13 @@ public abstract class Item {
     /** Whether this item can serve as a light source (when on, for switchables). */
     protected final boolean light;
 
+    /**
+     * Whether this item is scenery bolted to its room and cannot be taken.
+     * Fixed items (the front door, the chapel shrine, the boiler generator)
+     * remain usable in place but must never enter the player's inventory.
+     */
+    protected final boolean fixed;
+
     /**
      * Executes the item's primary action. Side effects (text output,
      * mutation of player state) flow through the given context.

Semesterprojekt/src/main/resources/world/items.yaml

@@ -40,6 +40,7 @@
 - type: plain
   id: valve
   name: Drainage Valve
+  fixed: true
   description: |
     A rusted drainage valve set into the cellar wall. Its wheel is missing —
     it is part of the house, not something you can carry off.
@@ -52,6 +53,7 @@
 - type: plain
   id: generator
   name: Generator
+  fixed: true
   description: |
     A rusty generator with an empty fuse socket. It is bolted to the floor —
     you will have to work on it where it stands.
@@ -71,6 +73,7 @@
 - type: plain
   id: shrine
   name: Stone Shrine
+  fixed: true
   description: |
     A small stone shrine with a shallow offering niche. It is mortared into
     the chapel floor — a place to leave something, not to take it.
@@ -80,6 +83,7 @@
 - type: switchable
   id: front_door
   name: Front Door
+  fixed: true
   description: The heavy front door. It would let you leave the manor for good.
   initialState: false
   onText: |
@@ -113,6 +117,7 @@
 - type: readable
   id: portrait
   name: Family Portrait
+  fixed: true
   description: A faded oil portrait above the dining-room hearth.
   readText: |
     A stern family poses before the manor. A small brass plate reads only:

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

@@ -0,0 +1,39 @@
+package thb.jeanluc.adventure.command.impl;
+
+import org.junit.jupiter.api.Test;
+import thb.jeanluc.adventure.model.item.PlainItem;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Scenery items are usable in place but must never enter the inventory —
+ * otherwise the front door could be carried off and opened from any room.
+ */
+class FixedItemTest {
+
+    @Test
+    void take_withFixedItem_leavesItInTheRoom() {
+        var w = new CommandTestSupport.World();
+        var door = PlainItem.builder()
+                .id("door").name("Front Door").description("heavy").fixed(true).build();
+        w.kitchen.addItem(door);
+
+        new TakeCommand().execute(w.ctx, List.of("door"));
+
+        assertThat(w.player.hasItem("door")).isFalse();
+        assertThat(w.kitchen.findItem("door")).isPresent();
+        assertThat(w.io.allOutput()).contains("part of the room");
+    }
+
+    @Test
+    void take_withOrdinaryItem_stillMovesItToInventory() {
+        var w = new CommandTestSupport.World();
+
+        new TakeCommand().execute(w.ctx, List.of("letter"));
+
+        assertThat(w.player.hasItem("letter")).isTrue();
+        assertThat(w.kitchen.findItem("letter")).isEmpty();
+    }
+}