From b00c6a1d60723622101512b13168214ff61696aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20Dach?= <dach.bartlomiej@gmail.com>
Date: Tue, 19 Jan 2021 18:29:55 +0100
Subject: [PATCH] Make first non-default skin index a property

The previous code was very brittle - it was not always updating
properly, and seems to have worked either by a carefully crafted set of
circumstances, or just plain coincidence.

Having this be a get-only property avoids potential error in the future
caused by not updating the index properly, at the expense of an added
linear lookup.
---
 .../Overlays/Settings/Sections/SkinSection.cs | 21 ++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/osu.Game/Overlays/Settings/Sections/SkinSection.cs b/osu.Game/Overlays/Settings/Sections/SkinSection.cs
index a3e472a9f9..bbb4c50f6b 100644
--- a/osu.Game/Overlays/Settings/Sections/SkinSection.cs
+++ b/osu.Game/Overlays/Settings/Sections/SkinSection.cs
@@ -38,7 +38,17 @@ namespace osu.Game.Overlays.Settings.Sections
 
         private List<SkinInfo> skinItems;
 
-        private int firstNonDefault;
+        private int firstNonDefaultSkinIndex
+        {
+            get
+            {
+                var index = skinItems.FindIndex(s => s.ID > 0);
+                if (index < 0)
+                    index = skinItems.Count;
+
+                return index;
+            }
+        }
 
         [Resolved]
         private SkinManager skins { get; set; }
@@ -114,10 +124,7 @@ namespace osu.Game.Overlays.Settings.Sections
         private void updateItems()
         {
             skinItems = skins.GetAllUsableSkins();
-            firstNonDefault = skinItems.FindIndex(s => s.ID > 0);
-            if (firstNonDefault < 0)
-                firstNonDefault = skinItems.Count;
-            skinItems.Insert(firstNonDefault, random_skin_info);
+            skinItems.Insert(firstNonDefaultSkinIndex, random_skin_info);
             skinItems = sortList(skinItems);
             skinDropdown.Items = skinItems;
         }
@@ -141,8 +148,8 @@ namespace osu.Game.Overlays.Settings.Sections
         private List<SkinInfo> sortList(List<SkinInfo> skinsList)
         {
             // Sort user skins seperate from built-in skins
-            List<SkinInfo> userSkinsList = skinsList.GetRange(firstNonDefault + 1, skinsList.Count - (firstNonDefault + 1));
-            skinsList.RemoveRange(firstNonDefault + 1, skinsList.Count - (firstNonDefault + 1));
+            List<SkinInfo> userSkinsList = skinsList.GetRange(firstNonDefaultSkinIndex, skinsList.Count - firstNonDefaultSkinIndex);
+            skinsList.RemoveRange(firstNonDefaultSkinIndex, skinsList.Count - firstNonDefaultSkinIndex);
             userSkinsList.Sort((a, b) => string.Compare(a.Name, b.Name, StringComparison.OrdinalIgnoreCase));
             skinsList.AddRange(userSkinsList);
             return skinsList;