From 9bca84dca459712928f734afaad5eb1ac24e8004 Mon Sep 17 00:00:00 2001
From: Michael Bucari-Tovo <mbucari1@gmail.com>
Date: Mon, 28 Jul 2025 09:29:17 -0600
Subject: [PATCH] Sort columns with null values always at the bottom

---
 Source/LibationUiBase/GridView/GridEntry.cs   | 19 ++++++++++++++-
 .../GridView/RowComparerBase.cs               | 23 +++++++++++++------
 2 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/Source/LibationUiBase/GridView/GridEntry.cs b/Source/LibationUiBase/GridView/GridEntry.cs
index 6f4549a2..665859f1 100644
--- a/Source/LibationUiBase/GridView/GridEntry.cs
+++ b/Source/LibationUiBase/GridView/GridEntry.cs
@@ -210,6 +210,24 @@ namespace LibationUiBase.GridView
 			nameof(IsSpatial) => IsSpatial,
 			_ => null
 		};
+		
+		public bool MemberValueIsDefault(string memberName) => memberName switch
+		{
+			nameof(Series) => Book.SeriesLink?.Any() is not true,
+			nameof(SeriesOrder) => string.IsNullOrWhiteSpace(SeriesOrder.OrderString),
+			nameof(MyRating) => RatingIsDefault(Book.UserDefinedItem.Rating),
+			nameof(ProductRating) => RatingIsDefault(Book.Rating),
+			nameof(Authors) => string.IsNullOrWhiteSpace(Authors),
+			nameof(Narrators) => string.IsNullOrWhiteSpace(Narrators),
+			nameof(Description) => string.IsNullOrWhiteSpace(Description),
+			nameof(Category) => string.IsNullOrWhiteSpace(Category),
+			nameof(Misc) => string.IsNullOrWhiteSpace(Misc),
+			nameof(BookTags) => string.IsNullOrWhiteSpace(BookTags),
+			_ => false
+		};
+
+		private static bool RatingIsDefault(Rating rating)
+			=> rating is null || (rating.OverallRating == 0 && rating.PerformanceRating == 0 && rating.StoryRating == 0);
 
 		public IComparer GetMemberComparer(Type memberType)
 			=> memberTypeComparers.TryGetValue(memberType, out IComparer value) ? value : memberTypeComparers[memberType.BaseType];
@@ -341,7 +359,6 @@ namespace LibationUiBase.GridView
 			return (await Task.WhenAll(tasks)).SelectMany(a => a).ToList();
 		}
 
-
 		~GridEntry()
 		{
 			PictureStorage.PictureCached -= PictureStorage_PictureCached;
diff --git a/Source/LibationUiBase/GridView/RowComparerBase.cs b/Source/LibationUiBase/GridView/RowComparerBase.cs
index dab24a38..91298207 100644
--- a/Source/LibationUiBase/GridView/RowComparerBase.cs
+++ b/Source/LibationUiBase/GridView/RowComparerBase.cs
@@ -21,15 +21,24 @@ namespace LibationUiBase.GridView
 
 		private int InternalCompare(GridEntry x, GridEntry y)
 		{
-			var val1 = x.GetMemberValue(PropertyName);
-			var val2 = y.GetMemberValue(PropertyName);
+			//Default values (e.g. empty strings) always sort to the end of the list.
+			var val1IsDefault = x.MemberValueIsDefault(PropertyName);
+			var val2IsDefault = y.MemberValueIsDefault(PropertyName);
 
-			var compare = x.GetMemberComparer(val1.GetType()).Compare(val1, val2);
+			if (val1IsDefault && val2IsDefault) return 0;
+			else if (val1IsDefault && !val2IsDefault) return GetSortOrder() is ListSortDirection.Ascending ? 1 : -1;
+			else if (!val1IsDefault && val2IsDefault) return GetSortOrder() is ListSortDirection.Ascending ? -1 : 1;
+			else
+			{
+				var val1 = x.GetMemberValue(PropertyName);
+				var val2 = y.GetMemberValue(PropertyName);
+				var compare = x.GetMemberComparer(val1.GetType()).Compare(val1, val2);
 
-			return compare == 0 && x.Liberate.IsSeries && y.Liberate.IsSeries
-				//Both a and b are series parents and compare as equal, so break the tie.
-				? x.AudibleProductId.CompareTo(y.AudibleProductId)
-				: compare;
+				return compare == 0 && x.Liberate.IsSeries && y.Liberate.IsSeries
+					//Both a and b are series parents and compare as equal, so break the tie.
+					? x.AudibleProductId.CompareTo(y.AudibleProductId)
+					: compare;
+			}
 		}
 
 		public int Compare(GridEntry? geA, GridEntry? geB)