From 11dab1eba74f6f92c780ba715ab136ab9989da27 Mon Sep 17 00:00:00 2001
From: NichtStudioCode <51272202+NichtStudioCode@users.noreply.github.com>
Date: Sat, 23 Apr 2022 18:18:46 +0200
Subject: [PATCH] Fixed background not working for nested GUIs

---
 .../de/studiocode/invui/gui/SlotElement.java     | 16 ++++++++++++++++
 .../studiocode/invui/window/impl/BaseWindow.java | 13 +++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/InvUI/src/main/java/de/studiocode/invui/gui/SlotElement.java b/InvUI/src/main/java/de/studiocode/invui/gui/SlotElement.java
index 29c6515..c0845ef 100644
--- a/InvUI/src/main/java/de/studiocode/invui/gui/SlotElement.java
+++ b/InvUI/src/main/java/de/studiocode/invui/gui/SlotElement.java
@@ -5,6 +5,8 @@ import de.studiocode.invui.item.ItemProvider;
 import de.studiocode.invui.virtualinventory.VirtualInventory;
 import org.bukkit.inventory.ItemStack;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.UUID;
 
 public interface SlotElement {
@@ -119,6 +121,20 @@ public interface SlotElement {
             }
         }
         
+        public List<GUI> getGuiList() {
+            ArrayList<GUI> guis = new ArrayList<>();
+            LinkedSlotElement element = this;
+            while (true) {
+                guis.add(element.getGui());
+                SlotElement below = element.getGui().getSlotElement(element.getSlotIndex());
+                if (below instanceof LinkedSlotElement)
+                    element = (LinkedSlotElement) below;
+                else break;
+            }
+            
+            return guis;
+        }
+        
         @Override
         public ItemStack getItemStack(UUID viewerUUID) {
             SlotElement holdingElement = getHoldingElement();
diff --git a/InvUI/src/main/java/de/studiocode/invui/window/impl/BaseWindow.java b/InvUI/src/main/java/de/studiocode/invui/window/impl/BaseWindow.java
index 31375c2..13b3217 100644
--- a/InvUI/src/main/java/de/studiocode/invui/window/impl/BaseWindow.java
+++ b/InvUI/src/main/java/de/studiocode/invui/window/impl/BaseWindow.java
@@ -5,6 +5,7 @@ import de.studiocode.invui.InvUI;
 import de.studiocode.invui.gui.GUI;
 import de.studiocode.invui.gui.SlotElement;
 import de.studiocode.invui.gui.SlotElement.ItemSlotElement;
+import de.studiocode.invui.gui.SlotElement.LinkedSlotElement;
 import de.studiocode.invui.gui.SlotElement.VISlotElement;
 import de.studiocode.invui.item.Item;
 import de.studiocode.invui.item.ItemProvider;
@@ -73,6 +74,18 @@ public abstract class BaseWindow implements Window {
             }
         } else if (element == null || (element instanceof VISlotElement && element.getItemStack(viewerUUID) == null)) {
             ItemProvider background = getGuiAt(index).getFirst().getBackground();
+            itemStack = background == null ? null : background.getFor(viewerUUID);
+        } else if (element instanceof LinkedSlotElement && element.getHoldingElement() == null) {
+            ItemProvider background = null;
+            
+            List<GUI> guis = ((LinkedSlotElement) element).getGuiList();
+            guis.add(0, getGuiAt(index).getFirst());
+            
+            for (int i = guis.size() - 1; i >= 0; i--) {
+                background = guis.get(i).getBackground();
+                if (background != null) break;
+            }
+            
             itemStack = background == null ? null : background.getFor(viewerUUID);
         } else itemStack = element.getItemStack(viewerUUID);
         setInvItem(index, itemStack);