Added more quest stuff including dialogic quest condition

scripts/CSharp/Common/Inventory/InventoryInstance.cs

@@ -2,6 +2,7 @@
 using System;
 using Godot;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Babushka.scripts.CSharp.Common.Inventory;
 
@@ -120,12 +121,29 @@ public partial class InventoryInstance : Node
     {
         if (destinationSlot < 0 || destinationSlot >= _slots.Count)
             return InventoryActionResult.DestinationDoesNotExists;
-        
+
         if (!_slots[destinationSlot].IsEmpty())
             return InventoryActionResult.DestinationFull;
-        
+
         _slots[destinationSlot].itemInstance = itemInstance;
         EmitSignal(SignalName.InventoryContentsChanged);
         return InventoryActionResult.Success;
     }
-}
+
+    public int TotalItemsOfBlueprint(ItemResource blueprint)
+    {
+        return _slots
+            .Where(i => !i.IsEmpty() && i.itemInstance!.blueprint == blueprint)
+            .Sum(i => i.itemInstance!.amount);
+    }
+
+    public bool HasItems(ItemInstance item)
+    {
+        return TotalItemsOfBlueprint(item.blueprint) >= item.amount;
+    }
+
+    public bool HasItems(IEnumerable<ItemInstance> items)
+    {
+        return items.All(HasItems);
+    }
+}

scripts/CSharp/Common/Inventory/ItemInstance.cs

@@ -1,9 +1,13 @@
-namespace Babushka.scripts.CSharp.Common.Inventory;
+using Godot;
+namespace Babushka.scripts.CSharp.Common.Inventory;
 
-public class ItemInstance
+// Do not instantiate this resource
+// But it has to be a resource because Godot
+[GlobalClass]
+public partial class ItemInstance: Resource 
 {
-    public ItemResource blueprint;
-    public int amount = 1;
+    [Export] public ItemResource blueprint;
+    [Export] public int amount = 1;
 
     public ItemInstance Clone()
     {