From 184fe8c1fce3e1de6b4d90ab1510d01eedd0c64f Mon Sep 17 00:00:00 2001
From: Sebastian Hartte <sebastian@hartte.de>
Date: Mon, 3 Aug 2020 22:29:03 +0200
Subject: [PATCH] Fix items being lost when trying to stack items in the player
 inventory.

---
 .../appeng/container/AEBaseContainer.java     | 28 +++++++++++++------
 .../appeng/container/slot/PlayerInvSlot.java  |  5 ++--
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/src/main/java/appeng/container/AEBaseContainer.java b/src/main/java/appeng/container/AEBaseContainer.java
index 7691abc15..17bb8eed2 100644
--- a/src/main/java/appeng/container/AEBaseContainer.java
+++ b/src/main/java/appeng/container/AEBaseContainer.java
@@ -95,8 +95,6 @@ public abstract class AEBaseContainer extends ScreenHandler {
     private boolean sentCustomName;
     private int ticksSinceCheck = 900;
     private IAEItemStack clientRequestedTargetItem = null;
-    // Slots that were created to represent the player inventory
-    private List<Slot> playerInventorySlots = null;
 
     public AEBaseContainer(ScreenHandlerType<?> containerType, int id, final PlayerInventory ip,
             final BlockEntity myTile, final IPart myPart) {
@@ -264,25 +262,39 @@ public abstract class AEBaseContainer extends ScreenHandler {
     }
 
     protected void bindPlayerInventory(final PlayerInventory playerInventory, final int offsetX, final int offsetY) {
-        FixedItemInv ih = new FixedInventoryVanillaWrapper(playerInventory);
+        FixedItemInv ih = new FixedInventoryVanillaWrapper(playerInventory) {
+            // Vanilla needs this to be modifiable otherwise stacking will eat items.
+            // FIXME FABRIC: Remove when LBA makes these mutable as per
+            // ModifiableFixedItemInv
+            @Override
+            public ItemStack getInvStack(int slot) {
+                return playerInventory.getStack(slot);
+            }
+        };
 
         // bind player inventory
         for (int i = 0; i < 3; i++) {
             for (int j = 0; j < 9; j++) {
-                if (this.locked.contains(j + i * 9 + 9)) {
-                    this.addSlot(new DisabledSlot(ih, j + i * 9 + 9, 8 + j * 18 + offsetX, offsetY + i * 18));
+                int invSlot = j + i * 9 + 9;
+                int x = 8 + j * 18 + offsetX;
+                int y = offsetY + i * 18;
+
+                if (this.locked.contains(invSlot)) {
+                    this.addSlot(new DisabledSlot(ih, invSlot, x, y));
                 } else {
-                    this.addSlot(new PlayerInvSlot(ih, j + i * 9 + 9, 8 + j * 18 + offsetX, offsetY + i * 18));
+                    this.addSlot(new PlayerInvSlot(ih, invSlot, x, y));
                 }
             }
         }
 
         // bind player hotbar
         for (int i = 0; i < 9; i++) {
+            int x = 8 + i * 18 + offsetX;
+            int y = 58 + offsetY;
             if (this.locked.contains(i)) {
-                this.addSlot(new DisabledSlot(ih, i, 8 + i * 18 + offsetX, 58 + offsetY));
+                this.addSlot(new DisabledSlot(ih, i, x, y));
             } else {
-                this.addSlot(new PlayerHotBarSlot(ih, i, 8 + i * 18 + offsetX, 58 + offsetY));
+                this.addSlot(new PlayerHotBarSlot(ih, i, x, y));
             }
         }
     }
diff --git a/src/main/java/appeng/container/slot/PlayerInvSlot.java b/src/main/java/appeng/container/slot/PlayerInvSlot.java
index e141ccfda..38cf92ffd 100644
--- a/src/main/java/appeng/container/slot/PlayerInvSlot.java
+++ b/src/main/java/appeng/container/slot/PlayerInvSlot.java
@@ -21,11 +21,10 @@ package appeng.container.slot;
 import alexiil.mc.lib.attributes.item.FixedItemInv;
 
 // there is nothing special about this slot, its simply used to represent the players inventory, vs a container slot.
-
 public class PlayerInvSlot extends AppEngSlot {
 
-    public PlayerInvSlot(final FixedItemInv par1iInventory, final int invSlot, final int x, final int y) {
-        super(par1iInventory, invSlot, x, y);
+    public PlayerInvSlot(final FixedItemInv inv, final int invSlot, final int x, final int y) {
+        super(inv, invSlot, x, y);
 
         this.setPlayerSide(true);
     }