Finished implementing xp shop. It allows users to buy frames and backgrounds if the user enables the feature in data/xp.yml. It can also be available only to patrons

src/NadekoBot/Db/Models/XpShopOwnedItem.cs

@@ -0,0 +1,17 @@
+using NadekoBot.Services.Database.Models;
+
+namespace NadekoBot.Db.Models;
+
+public class XpShopOwnedItem : DbEntity
+{
+    public ulong UserId { get; set; }
+    public XpShopItemType ItemType { get; set; }
+    public bool IsUsing { get; set; }
+    public string ItemKey { get; set; }
+}
+
+public enum XpShopItemType
+{
+    Background,
+    Frame,
+}

src/NadekoBot/Db/NadekoContext.cs

@@ -454,6 +454,23 @@ public abstract class NadekoContext : DbContext
         });
 
         #endregion
+ 
+        #region Xp Item Shop
+
+        modelBuilder.Entity<XpShopOwnedItem>(
+            x =>
+            {
+                // user can own only one of each item
+                x.HasIndex(model => new
+                    {
+                        model.UserId,
+                        model.ItemType,
+                        model.ItemKey
+                    })
+                    .IsUnique();
+            });
+
+        #endregion
     }
 
 #if DEBUG