bugfix #1925: show orphaned episodes as standalone rows

Co-authored-by: rmcrackan <rmcrackan@gmail.com>

Source/AudibleUtilities/ApiExtended.cs

@@ -143,8 +143,10 @@ public class ApiExtended
 		var importEpisodes = Configuration.Instance.ImportEpisodes;
 		var importPlusTitles = Configuration.Instance.ImportPlusTitles;
 
-		List<Item> items = new();
-		int libraryItemCount = 0, episodeItemsExcluded = 0, plusTitlesExcluded = 0;
+		var items = new List<Item>();
+		var libraryItemCount = 0;
+		var episodeItemsExcluded = 0;
+		var plusTitlesExcluded = 0;
 		var sw = Stopwatch.StartNew();
 		var totalTime = TimeSpan.Zero;
 		using var semaphore = new SemaphoreSlim(MaxConcurrency);
@@ -378,7 +380,7 @@ public class ApiExtended
 		var items = await fetch(asins);
 		var missing = GetMissingAsins(asins, items);
 
-		for (int attempt = 1; attempt <= maxRetries && missing.Count > 0; attempt++)
+		for (var attempt = 1; attempt <= maxRetries && missing.Count > 0; attempt++)
 		{
 			onRetry?.Invoke(attempt);
 

Source/DataLayer/QueryObjects/LibraryBookQueries.cs

@@ -108,6 +108,16 @@ public static class LibraryBookQueries
 					.ParentedEpisodes()
 					.Select(ge => ge.Book.AudibleProductId), ge => ge.Book.AudibleProductId);
 
+		/// <summary>
+		/// Books displayed as top-level rows: ordinary products plus episodes whose series parent
+		/// is not in the database. Showing orphaned episodes here keeps a successfully imported
+		/// title discoverable instead of silently hiding it from both grids.
+		/// </summary>
+		public IEnumerable<LibraryBook> StandaloneBooks()
+			=> libraryBooks
+				.Where(lb => lb.Book.IsProduct())
+				.Concat(libraryBooks.FindOrphanedEpisodes());
+
 		public IEnumerable<LibraryBook> FindChildren(LibraryBook parent)
 			=> libraryBooks.Where(lb => lb.Book.IsEpisodeChild() && lb.HasSeriesId(parent.Book.AudibleProductId));
 

Source/LibationAvalonia/ViewModels/ProductsDisplayViewModel.cs

@@ -162,6 +162,7 @@ public class ProductsDisplayViewModel : ViewModelBase
 		var allEntries = SOURCE.BookEntries().ToDictionarySafe(b => b.AudibleProductId);
 		var seriesEntries = SOURCE.SeriesEntries().ToList();
 		var parentedEpisodes = dbBooks.ParentedEpisodes().ToHashSet();
+		var orphanedEpisodes = dbBooks.FindOrphanedEpisodes().ToHashSet();
 
 		await Dispatcher.UIThread.InvokeAsync(() =>
 		{
@@ -169,11 +170,31 @@ public class ProductsDisplayViewModel : ViewModelBase
 			{
 				var existingEntry = allEntries.TryGetValue(libraryBook.Book.AudibleProductId, out var e) ? e : null;
 
-				if (libraryBook.Book.IsProduct())
+				if (libraryBook.Book.IsProduct() || orphanedEpisodes.Contains(libraryBook))
+				{
+					// An episode can become orphaned when its parent is removed. Move it out from under
+					// the old parent and keep it visible as a standalone row.
+					if (existingEntry?.Parent is not null)
+					{
+						existingEntry.Parent.RemoveChild(existingEntry);
+						RemoveBooks([existingEntry], []);
+						existingEntry = null;
+					}
+
 					UpsertBook(libraryBook, existingEntry);
+				}
 				else if (parentedEpisodes.Contains(libraryBook))
-					//Only try to add or update is this LibraryBook is a know child of a parent
+				{
+					// If a formerly orphaned episode now has a parent, remove its standalone row
+					// before recreating it beneath that parent.
+					if (existingEntry is { Parent: null })
+					{
+						RemoveBooks([existingEntry], []);
+						existingEntry = null;
+					}
+
 					UpsertEpisode(libraryBook, existingEntry, seriesEntries, dbBooks);
+				}
 			}
 		});
 

Source/LibationUiBase/GridView/LibraryBookEntry.cs

@@ -32,11 +32,14 @@ public class LibraryBookEntry : GridEntry
 	}
 
 	/// <summary>
-	/// Creates <see cref="LibraryBookEntry{TStatus}"/> for all non-episode books in an enumeration of <see cref="LibraryBook"/>.
+	/// Creates <see cref="LibraryBookEntry{TStatus}"/> for ordinary books and episodes whose series parent is missing.
 	/// </summary>
 	/// <remarks>Can be called from any thread, but requires the calling thread's <see cref="System.Threading.SynchronizationContext.Current"/> to be valid.</remarks>
 	public static async Task<List<GridEntry>> GetAllProductsAsync(IEnumerable<LibraryBook> libraryBooks)
-		=> await GetAllProductsAsync(libraryBooks, lb => lb.Book.IsProduct(), lb => new LibraryBookEntry(lb) as GridEntry);
+		=> await GetAllProductsAsync(
+			libraryBooks.StandaloneBooks(),
+			_ => true,
+			lb => new LibraryBookEntry(lb) as GridEntry);
 
 	protected override string? GetBookTags()
 		=> Book is null ? null : string.Join("\r\n", Book.UserDefinedItem.TagsEnumerated);

Source/LibationWinForms/GridView/ProductsGrid.cs

@@ -350,6 +350,7 @@ public partial class ProductsGrid : UserControl
 		var allEntries = bindingList.AllItems().BookEntries().ToDictionarySafe(b => b.AudibleProductId);
 		var seriesEntries = bindingList.AllItems().SeriesEntries().ToList();
 		var parentedEpisodes = dbBooks.ParentedEpisodes().ToHashSet();
+		var orphanedEpisodes = dbBooks.FindOrphanedEpisodes().ToHashSet();
 
 		//Get the UI thread's synchronization context and set it on the current thread to ensure
 		//it's available for creation of new IGridEntry items during upsert
@@ -361,14 +362,30 @@ public partial class ProductsGrid : UserControl
 		{
 			var existingEntry = allEntries.TryGetValue(libraryBook.Book.AudibleProductId, out var e) ? e : null;
 
-			if (libraryBook.Book.IsProduct())
+			if (libraryBook.Book.IsProduct() || orphanedEpisodes.Contains(libraryBook))
 			{
+				// An episode can become orphaned when its parent is removed. Move it out from under
+				// the old parent and keep it visible as a standalone row.
+				if (existingEntry?.Parent is not null)
+				{
+					existingEntry.Parent.RemoveChild(existingEntry);
+					bindingList.Remove(existingEntry);
+					existingEntry = null;
+				}
+
 				AddOrUpdateBook(libraryBook, existingEntry);
 				continue;
 			}
 			if (parentedEpisodes.Contains(libraryBook))
 			{
-				//Only try to add or update is this LibraryBook is a know child of a parent
+				// If a formerly orphaned episode now has a parent, remove its standalone row
+				// before recreating it beneath that parent.
+				if (existingEntry is { Parent: null })
+				{
+					bindingList.Remove(existingEntry);
+					existingEntry = null;
+				}
+
 				AddOrUpdateEpisode(libraryBook, existingEntry, seriesEntries, dbBooks);
 			}
 		}

Source/_Tests/LibationUiBase.Tests/StandaloneBooksTests.cs

@@ -0,0 +1,73 @@
+using DataLayer;
+
+namespace LibationUiBase.Tests;
+
+[TestClass]
+public class StandaloneBooksTests
+{
+	private static LibraryBook libraryBook(string asin, ContentType contentType, string? seriesAsin = null)
+	{
+		var contributor = Contributor.GetEmpty();
+		var book = new Book(
+			new AudibleProductId(asin),
+			asin,
+			null,
+			null,
+			1,
+			contentType,
+			[contributor],
+			[contributor],
+			"us");
+
+		if (seriesAsin is not null)
+			book.UpsertSeries(new Series(new AudibleSeriesId(seriesAsin), $"Series {seriesAsin}"), "1");
+
+		return new LibraryBook(book, new DateTime(2026, 8, 10), "account");
+	}
+
+	[TestMethod]
+	public void ordinary_books_are_standalone()
+	{
+		var product = libraryBook("BOOK", ContentType.Product);
+
+		var standalone = new[] { product }.StandaloneBooks().ToList();
+
+		CollectionAssert.AreEqual(new[] { "BOOK" }, standalone.Select(lb => lb.Book.AudibleProductId).ToList());
+	}
+
+	[TestMethod]
+	public void episode_without_its_parent_is_standalone()
+	{
+		var orphan = libraryBook("EPISODE", ContentType.Episode, "SHOW");
+
+		var standalone = new[] { orphan }.StandaloneBooks().ToList();
+
+		CollectionAssert.AreEqual(new[] { "EPISODE" }, standalone.Select(lb => lb.Book.AudibleProductId).ToList());
+	}
+
+	[TestMethod]
+	public void episode_with_its_parent_is_not_standalone()
+	{
+		var parent = libraryBook("SHOW", ContentType.Parent, "SHOW");
+		var episode = libraryBook("EPISODE", ContentType.Episode, "SHOW");
+
+		var standalone = new[] { parent, episode }.StandaloneBooks().ToList();
+
+		Assert.AreEqual(0, standalone.Count);
+	}
+
+	[TestMethod]
+	public void products_and_orphans_are_returned_but_parents_and_parented_episodes_are_not()
+	{
+		var product = libraryBook("BOOK", ContentType.Product);
+		var parent = libraryBook("SHOW", ContentType.Parent, "SHOW");
+		var child = libraryBook("CHILD", ContentType.Episode, "SHOW");
+		var orphan = libraryBook("ORPHAN", ContentType.Episode, "MISSING_SHOW");
+
+		var standalone = new[] { product, parent, child, orphan }.StandaloneBooks().ToList();
+
+		CollectionAssert.AreEquivalent(
+			new[] { "BOOK", "ORPHAN" },
+			standalone.Select(lb => lb.Book.AudibleProductId).ToList());
+	}
+}