Collapse version groups to the primary version in queries

1 files changed, 7 insertions, 4 deletions

diff --git a/Jellyfin.Server.Implementations/Item/BaseItemRepository.QueryBuilding.cs b/Jellyfin.Server.Implementations/Item/BaseItemRepository.QueryBuilding.cs
index d6ddf8f5c8..decd45ae2c 100644
--- a/Jellyfin.Server.Implementations/Item/BaseItemRepository.QueryBuilding.cs
+++ b/Jellyfin.Server.Implementations/Item/BaseItemRepository.QueryBuilding.cs
@@ -62,18 +62,21 @@ public sealed partial class BaseItemRepository
 
     private IQueryable<BaseItemEntity> ApplyGroupingFilter(JellyfinDbContext context, IQueryable<BaseItemEntity> dbQuery, InternalItemsQuery filter)
     {
-        // Collapse duplicates sharing a presentation key (e.g. alternate versions) by picking
-        // the min Id per group. Keep the grouped ids as an IQueryable sub-select; materializing
+        // Collapse duplicates sharing a presentation key (e.g. alternate versions), preferring the
+        // primary version (PrimaryVersionId is null) so detail pages and actions target it instead
+        // of an arbitrary alternate. Keep the grouped ids as an IQueryable sub-select; materializing
         // to a List would inline one bound parameter per id and hit SQLite's variable cap.
         var enableGroupByPresentationUniqueKey = EnableGroupByPresentationUniqueKey(filter);
         if (enableGroupByPresentationUniqueKey && filter.GroupBySeriesPresentationUniqueKey)
         {
-            var groupedIds = dbQuery.GroupBy(e => new { e.PresentationUniqueKey, e.SeriesPresentationUniqueKey }).Select(e => e.Min(x => x.Id));
+            var groupedIds = dbQuery.GroupBy(e => new { e.PresentationUniqueKey, e.SeriesPresentationUniqueKey })
+                .Select(g => g.Where(e => e.PrimaryVersionId == null).Min(e => (Guid?)e.Id) ?? g.Min(e => (Guid?)e.Id));
             dbQuery = context.BaseItems.AsNoTracking().Where(e => groupedIds.Contains(e.Id));
         }
         else if (enableGroupByPresentationUniqueKey)
         {
-            var groupedIds = dbQuery.GroupBy(e => e.PresentationUniqueKey).Select(e => e.Min(x => x.Id));
+            var groupedIds = dbQuery.GroupBy(e => e.PresentationUniqueKey)
+                .Select(g => g.Where(e => e.PrimaryVersionId == null).Min(e => (Guid?)e.Id) ?? g.Min(e => (Guid?)e.Id));
             dbQuery = context.BaseItems.AsNoTracking().Where(e => groupedIds.Contains(e.Id));
         }
         else if (filter.GroupBySeriesPresentationUniqueKey)