fix: clear a plate's sauce once its last food is taken off

The sauce visual stayed on a plate after its food was removed, so hasSauce
rejected sauce for every later dish on that plate (reported with chicken
legs, but any food was affected). Remove the sauce slot when the last food
leaves, clear leftover sauce on plates saved before this fix, and keep the
ladle full when sauce is ladled onto an empty plate.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: XxFran10xX

src/main/java/net/tfminecraft/cooking/manager/PlateManager.java

@@ -10,6 +10,7 @@
 import org.bukkit.Sound;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
@@ -31,6 +32,7 @@
 import net.tfminecraft.interactiblefurniture.events.FurnitureBreakEvent;
 import net.tfminecraft.interactiblefurniture.events.FurnitureInteractEvent;
 import net.tfminecraft.interactiblefurniture.events.FurnitureSlotItemAddEvent;
+import net.tfminecraft.interactiblefurniture.events.FurnitureSlotItemTakeEvent;
 import net.tfminecraft.interactiblefurniture.furniture.Furniture;
 import net.tfminecraft.interactiblefurniture.furniture.PlacedSlot;
 import net.tfminecraft.interactiblefurniture.furniture.data.DisplayData;
@@ -56,6 +58,11 @@ public void run() {
     }
 
     public void update(Furniture f) {
+        // Also clears plates saved with leftover sauce before the take handler existed.
+        if(hasLeftoverSauce(f, null)) {
+            f.removeActiveSlot("sauce");
+            InteractibleFurniture.getInstance().getFurnitureManager().persistFurniture(f);
+        }
         for(PlacedSlot slot : f.getActiveSlots().values()) {
             if(slot.getId().contains("display")) continue;
             ItemStack item = slot.getCurrentItem();
@@ -99,10 +106,35 @@ public boolean hasSauce(Furniture f) {
         return false;
     }
 
+    /**
+     * True when the plate shows a sauce visual but no food would remain once {@code leavingSlot}
+     * is gone. A leftover sauce visual makes hasSauce reject the next dish on the plate.
+     */
+    boolean hasLeftoverSauce(Furniture f, String leavingSlot) {
+        if(!f.hasActiveSlot("sauce")) return false;
+        for(String id : f.getActiveSlots().keySet()) {
+            if(id.equals("sauce") || id.equals(leavingSlot)) continue;
+            return false;
+        }
+        return true;
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+    public void takeItem(FurnitureSlotItemTakeEvent e) {
+        Furniture f = e.getFurniture();
+        if(!FurnitureCache.isPlate(f)) return;
+        // The taken slot is still active here; InteractibleFurniture removes it and saves the plate next.
+        if(hasLeftoverSauce(f, e.getSlot().getId())) {
+            f.removeActiveSlot("sauce");
+        }
+    }
+
     // Keep the existing legacy text representation, formatting, and exact-string comparisons.
     @SuppressWarnings("deprecation")
     public void addSauce(Player p, Furniture f, FoodItem sauce, ItemStack base) {
         if (hasSauce(f)) return;
+        // Sauce on an empty plate would never reach food added later, so keep the ladle full.
+        if (f.getActiveSlots().isEmpty()) return;
 
         // Replace player ladle with empty ladle
         p.getInventory().setItemInMainHand(

src/test/java/net/tfminecraft/cooking/manager/PlateManagerTest.java

@@ -116,4 +116,45 @@ public boolean hasItemMeta() {
 
         assertFalse(new PlateManager().hasSauce(plate));
     }
+
+    @Test
+    void sauceIsLeftoverOnceTheLastFoodLeaves() {
+        Furniture plate = plateWithSauceVisual();
+        plate.getActiveSlots().put("item_1", new PlacedSlot(plate, "item_1"));
+
+        assertFalse(new PlateManager().hasLeftoverSauce(plate, null));
+        assertTrue(new PlateManager().hasLeftoverSauce(plate, "item_1"));
+    }
+
+    @Test
+    void sauceStaysWhileOtherFoodRemains() {
+        Furniture plate = plateWithSauceVisual();
+        plate.getActiveSlots().put("item_1", new PlacedSlot(plate, "item_1"));
+        plate.getActiveSlots().put("item_2", new PlacedSlot(plate, "item_2"));
+
+        assertFalse(new PlateManager().hasLeftoverSauce(plate, "item_1"));
+    }
+
+    @Test
+    void sauceAloneOnAPlateIsLeftover() {
+        assertTrue(new PlateManager().hasLeftoverSauce(plateWithSauceVisual(), null));
+    }
+
+    @Test
+    void plateWithoutSauceHasNoLeftover() {
+        Furniture plate = new Furniture("plate", null, UUID.randomUUID());
+        plate.getActiveSlots().put("item_1", new PlacedSlot(plate, "item_1"));
+
+        assertFalse(new PlateManager().hasLeftoverSauce(plate, null));
+        assertFalse(new PlateManager().hasLeftoverSauce(plate, "item_1"));
+    }
+
+    @Test
+    void sauceOnAnEmptyPlateReturnsBeforeTouchingThePlayerOrLadle() {
+        Furniture plate = new Furniture("plate", null, UUID.randomUUID());
+
+        // Null interaction arguments ensure the empty-plate attempt exits before using them.
+        assertDoesNotThrow(() -> new PlateManager().addSauce(null, plate, null, null));
+        assertTrue(plate.getActiveSlots().isEmpty());
+    }
 }