itemstack syncing for inevntory

Minecraft.Server.FourKit/Inventory/Inventory.cs

@@ -51,10 +51,16 @@ public class Inventory : IEnumerable<ItemStack>
             int id = buf[i * 3];
             int count = buf[i * 3 + 1];
             int aux = buf[i * 3 + 2];
+            _items[i]?.UnbindFromInventory();
             if (id > 0 && count > 0)
+            {
                 _items[i] = new ItemStack(id, count, (short)aux);
+                _items[i]!.BindToInventory(this, i);
+            }
             else
+            {
                 _items[i] = null;
+            }
         }
     }
 
@@ -79,7 +85,9 @@ public class Inventory : IEnumerable<ItemStack>
     {
         EnsureSynced();
         if (index < 0 || index >= _items.Length) return null;
-        return _items[index];
+        var item = _items[index];
+        item?.BindToInventory(this, index);
+        return item;
     }
 
     /// <summary>
@@ -91,6 +99,12 @@ public class Inventory : IEnumerable<ItemStack>
     {
         if (index >= 0 && index < _items.Length)
         {
+            var old = _items[index];
+            if (old != item)
+            {
+                old?.UnbindFromInventory();
+                item?.BindToInventory(this, index);
+            }
             _items[index] = item;
             _slotModifiedByPlugin = true;
         }
@@ -569,6 +583,9 @@ public class Inventory : IEnumerable<ItemStack>
     {
         for (int i = start; i < _items.Length; i++)
             if (_items[i] != null)
+            {
+                _items[i]!.BindToInventory(this, i);
                 yield return _items[i]!;
+            }
     }
 }

Minecraft.Server.FourKit/Inventory/ItemStack.cs

@@ -11,6 +11,8 @@ public class ItemStack
     private int _amount;
     private short _durability;
     private ItemMeta? _meta;
+    internal Inventory? _ownerInventory;
+    internal int _ownerSlot = -1;
 
     /// <summary>
     /// Creates a new ItemStack of the specified material with amount 1.
@@ -62,7 +64,7 @@ public class ItemStack
     /// Sets the type of this item.
     /// </summary>
     /// <param name="type">New type to set the items in this stack to.</param>
-    public void setType(Material type) => _type = type;
+    public void setType(Material type) { _type = type; SyncToOwner(); }
 
     /// <summary>
     /// Gets the type id for this item.
@@ -77,6 +79,7 @@ public class ItemStack
     public void setTypeId(int type)
     {
         _type = Enum.IsDefined(typeof(Material), type) ? (Material)type : Material.AIR;
+        SyncToOwner();
     }
 
     /// <summary>
@@ -89,7 +92,7 @@ public class ItemStack
     /// Sets the amount of items in this stack.
     /// </summary>
     /// <param name="amount">New amount of items in this stack.</param>
-    public void setAmount(int amount) => _amount = amount;
+    public void setAmount(int amount) { _amount = amount; SyncToOwner(); }
 
     /// <summary>
     /// Gets the durability of this item.
@@ -101,7 +104,7 @@ public class ItemStack
     /// Sets the durability of this item.
     /// </summary>
     /// <param name="durability">Durability of this item.</param>
-    public void setDurability(short durability) => _durability = durability;
+    public void setDurability(short durability) { _durability = durability; SyncToOwner(); }
 
     /// <summary>
     /// Get a copy of this ItemStack's ItemMeta.
@@ -129,4 +132,22 @@ public class ItemStack
     internal ItemMeta? getItemMetaInternal() => _meta;
 
     internal void setItemMetaInternal(ItemMeta? meta) => _meta = meta;
+
+    internal void BindToInventory(Inventory inventory, int slot)
+    {
+        _ownerInventory = inventory;
+        _ownerSlot = slot;
+    }
+
+    internal void UnbindFromInventory()
+    {
+        _ownerInventory = null;
+        _ownerSlot = -1;
+    }
+
+    private void SyncToOwner()
+    {
+        if (_ownerInventory != null && _ownerSlot >= 0)
+            _ownerInventory.setItem(_ownerSlot, this);
+    }
 }

Minecraft.Server.FourKit/Inventory/PlayerInventory.cs

@@ -44,6 +44,7 @@ public class PlayerInventory : Inventory
             int id = buf[i * 3];
             int count = buf[i * 3 + 1];
             int aux = buf[i * 3 + 2];
+            _items[i]?.UnbindFromInventory();
             if (id > 0 && count > 0)
             {
                 var stack = new ItemStack(id, count, (short)aux);
@@ -51,6 +52,7 @@ public class PlayerInventory : Inventory
                 if (meta != null)
                     stack.setItemMetaInternal(meta);
                 _items[i] = stack;
+                stack.BindToInventory(this, i);
             }
             else
             {