Don't read episode markers in episode titles as a multi-episode range

4 files changed, 18 insertions, 14 deletions

diff --git a/Emby.Naming/TV/EpisodePathParser.cs b/Emby.Naming/TV/EpisodePathParser.cs
index 0c737964b4..f06aa909ba 100644
--- a/Emby.Naming/TV/EpisodePathParser.cs
+++ b/Emby.Naming/TV/EpisodePathParser.cs
@@ -158,7 +158,9 @@ namespace Emby.Naming.TV
                         if (nextIndex >= name.Length
                             || !"0123456789iIpP".Contains(name[nextIndex], StringComparison.Ordinal))
                         {
-                            if (int.TryParse(endingNumberGroup.ValueSpan, NumberStyles.Integer, CultureInfo.InvariantCulture, out num))
+                            // A range cannot end before it starts, so a lower number belongs to the episode title rather than to a range.
+                            if (int.TryParse(endingNumberGroup.ValueSpan, NumberStyles.Integer, CultureInfo.InvariantCulture, out num)
+                                && num >= result.EpisodeNumber)
                             {
                                 result.EndingEpisodeNumber = num;
                             }
@@ -226,7 +228,7 @@ namespace Emby.Naming.TV
                     info.SeriesName = result.SeriesName;
                 }
 
-                if (!info.EndingEpisodeNumber.HasValue && info.EpisodeNumber.HasValue)
+                if (!info.EndingEpisodeNumber.HasValue && result.EndingEpisodeNumber >= info.EpisodeNumber)
                 {
                     info.EndingEpisodeNumber = result.EndingEpisodeNumber;
                 }
diff --git a/MediaBrowser.Providers/TV/EpisodeMetadataService.cs b/MediaBrowser.Providers/TV/EpisodeMetadataService.cs
index 4ec6afe45b..f662ac2367 100644
--- a/MediaBrowser.Providers/TV/EpisodeMetadataService.cs
+++ b/MediaBrowser.Providers/TV/EpisodeMetadataService.cs
@@ -44,18 +44,16 @@ public class EpisodeMetadataService : MetadataService<Episode, EpisodeInfo>
     {
         var updatedType = base.BeforeSaveInternal(item, isFullRefresh, updateType);
 
-        // An episode cannot end before it starts. Providers and nfo files occasionally report the range
-        // transposed, which makes clients render the episode number backwards. Both numbers describe the
-        // same set of episodes either way, so restore their order instead of dropping the range.
-        if (item.IndexNumber.HasValue && item.IndexNumberEnd < item.IndexNumber)
+        // An episode cannot end before it starts.
+        if (item.IndexNumberEnd < item.IndexNumber)
         {
             Logger.LogWarning(
-                "Correcting reversed episode range {IndexNumber}-{IndexNumberEnd} for {Path}",
-                item.IndexNumber,
+                "Discarding episode range end {IndexNumberEnd} preceding episode number {IndexNumber} for {Path}",
                 item.IndexNumberEnd,
+                item.IndexNumber,
                 item.Path);
 
-            (item.IndexNumber, item.IndexNumberEnd) = (item.IndexNumberEnd, item.IndexNumber);
+            item.IndexNumberEnd = null;
             updatedType |= ItemUpdateType.MetadataImport;
         }
         else if (item.IndexNumberEnd.HasValue && !item.IndexNumber.HasValue)
diff --git a/tests/Jellyfin.Naming.Tests/TV/MultiEpisodeTests.cs b/tests/Jellyfin.Naming.Tests/TV/MultiEpisodeTests.cs
index 7e708c681d..4236749423 100644
--- a/tests/Jellyfin.Naming.Tests/TV/MultiEpisodeTests.cs
+++ b/tests/Jellyfin.Naming.Tests/TV/MultiEpisodeTests.cs
@@ -74,6 +74,9 @@ namespace Jellyfin.Naming.Tests.TV
         [InlineData("Season 5/S05E23 11-59 [HDTV-1080p][x265 AC3].mkv", null)]
         [InlineData("Season 5/S05E23 11-59 [HDTV-1080p][HEVC AC3].mkv", null)]
         [InlineData("Season 1/S01E01 1-23-45 [Bluray-1080p][AV1 Opus].mkv", null)]
+        // Episode markers in the episode title must not be read as an episode range
+        [InlineData("Season 03/Star Trek Enterprise (2001) - S03E21 - E2 (1080p BluRay x265).mkv", null)]
+        [InlineData("Season 02/Series Name (2001) - S02E10 - E5 [WEBRip-1080p].mkv", null)]
         public void TestGetEndingEpisodeNumberFromFile(string filename, int? endingEpisodeNumber)
         {
             var result = _episodePathParser.Parse(filename, false);
diff --git a/tests/Jellyfin.Providers.Tests/TV/EpisodeMetadataServiceTests.cs b/tests/Jellyfin.Providers.Tests/TV/EpisodeMetadataServiceTests.cs
index 24fd6a58e9..ea762256db 100644
--- a/tests/Jellyfin.Providers.Tests/TV/EpisodeMetadataServiceTests.cs
+++ b/tests/Jellyfin.Providers.Tests/TV/EpisodeMetadataServiceTests.cs
@@ -104,9 +104,10 @@ public sealed class EpisodeMetadataServiceTests : IDisposable
     }
 
     [Theory]
-    [InlineData(2, 1)] // e.g. an nfo with its episodedetails blocks in descending order
+    [InlineData(2, 1)]
     [InlineData(22, 21)]
-    public void BeforeSave_ReversedEpisodeRange_RestoresOrder(int indexNumber, int indexNumberEnd)
+    [InlineData(21, 2)] // e.g. "Series - S03E21 - E2 (1080p BluRay x265).mkv", where "E2" is the episode title
+    public void BeforeSave_ReversedEpisodeRange_ClearsIndexNumberEnd(int indexNumber, int indexNumberEnd)
     {
         var item = new Episode
         {
@@ -116,9 +117,9 @@ public sealed class EpisodeMetadataServiceTests : IDisposable
 
         var updateType = _service.BeforeSave(item);
 
-        // The range still covers the same episodes, it is just no longer transposed
-        Assert.Equal(indexNumberEnd, item.IndexNumber);
-        Assert.Equal(indexNumber, item.IndexNumberEnd);
+        // The episode number identifies the item, so it is kept and the impossible range is dropped
+        Assert.Equal(indexNumber, item.IndexNumber);
+        Assert.Null(item.IndexNumberEnd);
         Assert.True(updateType.HasFlag(ItemUpdateType.MetadataImport));
     }