1 files changed, 158 insertions, 1 deletions
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Item/ItemCountServiceTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Item/ItemCountServiceTests.cs
index 0766ca8d1e..947cf54d85 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Item/ItemCountServiceTests.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Item/ItemCountServiceTests.cs
@@ -7,6 +7,7 @@ using Jellyfin.Database.Implementations.Locking;
 using Jellyfin.Database.Providers.Sqlite;
 using Jellyfin.Server.Implementations.Item;
 using MediaBrowser.Common.Configuration;
+using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.Persistence;
 using Microsoft.Data.Sqlite;
@@ -14,6 +15,7 @@ using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Logging.Abstractions;
 using Moq;
 using Xunit;
+using LinkedChildType = Jellyfin.Database.Implementations.Entities.LinkedChildType;
 
 namespace Jellyfin.Server.Implementations.Tests.Item;
 
@@ -43,10 +45,18 @@ public sealed class ItemCountServiceTests : IDisposable
         var factory = new Mock<IDbContextFactory<JellyfinDbContext>>();
         factory.Setup(f => f.CreateDbContext()).Returns(CreateDbContext);
 
+        var queryHelpers = new Mock<IItemQueryHelpers>();
+        queryHelpers
+            .Setup(h => h.ApplyAccessFiltering(
+                It.IsAny<JellyfinDbContext>(),
+                It.IsAny<IQueryable<BaseItemEntity>>(),
+                It.IsAny<InternalItemsQuery>()))
+            .Returns((JellyfinDbContext _, IQueryable<BaseItemEntity> query, InternalItemsQuery _) => query);
+
         _service = new ItemCountService(
             factory.Object,
             new Mock<IItemTypeLookup>().Object,
-            new Mock<IItemQueryHelpers>().Object);
+            queryHelpers.Object);
     }
 
     public void Dispose()
@@ -106,6 +116,153 @@ public sealed class ItemCountServiceTests : IDisposable
         Assert.Equal(parentIds.Count, result.Count);
     }
 
+    [Fact]
+    public void GetCounts_MergedFolders_CountLeavesOfEveryFolderInTheGroup()
+    {
+        // Two folder-items of one merged series: same presentation key, a leaf each, one of them played.
+        var (user, seriesA, seriesB) = SeedMergedSeries(out var playedLeafId);
+
+        var filter = new InternalItemsQuery(user);
+
+        // Either folder-item stands for the whole merged series, so both must report the group.
+        foreach (var seriesId in new[] { seriesA, seriesB })
+        {
+            Assert.Equal(2, _service.GetTotalCount(filter, seriesId));
+            Assert.Equal(1, _service.GetPlayedCount(filter, seriesId));
+            Assert.Equal((1, 2), _service.GetPlayedAndTotalCount(filter, seriesId));
+        }
+
+        var batch = _service.GetPlayedAndTotalCountBatch([seriesA], user);
+        Assert.Equal((1, 2), batch[seriesA]);
+
+        Assert.NotEqual(Guid.Empty, playedLeafId);
+    }
+
+    [Fact]
+    public void GetCounts_UnmergedFolder_CountsOnlyItsOwnLeaves()
+    {
+        var (user, _, _) = SeedMergedSeries(out _);
+
+        // A folder with a key of its own must not pick up anything from the merged pair.
+        var loneSeriesId = Guid.NewGuid();
+        var loneLeafId = Guid.NewGuid();
+
+        using (var context = CreateDbContext())
+        {
+            var lone = CreateItem(loneSeriesId);
+            lone.PresentationUniqueKey = "lone-series";
+            context.BaseItems.Add(lone);
+            context.BaseItems.Add(CreateLeaf(loneLeafId));
+            context.SaveChanges();
+            AddAncestor(context, loneLeafId, loneSeriesId);
+            context.SaveChanges();
+        }
+
+        var filter = new InternalItemsQuery(user);
+
+        Assert.Equal(1, _service.GetTotalCount(filter, loneSeriesId));
+        Assert.Equal(0, _service.GetPlayedCount(filter, loneSeriesId));
+        Assert.Equal((0, 1), _service.GetPlayedAndTotalCount(filter, loneSeriesId));
+    }
+
+    [Fact]
+    public void GetChildCountBatch_MergedFolders_CountsDistinctChildKeys()
+    {
+        var seriesA = Guid.NewGuid();
+        var seriesB = Guid.NewGuid();
+
+        using (var context = CreateDbContext())
+        {
+            foreach (var id in new[] { seriesA, seriesB })
+            {
+                var series = CreateItem(id);
+                series.PresentationUniqueKey = "merged-series";
+                context.BaseItems.Add(series);
+            }
+
+            // Each folder-item holds a "Season 1"; those two share a key and are one season to the user.
+            var sharedSeasonA = CreateItem(Guid.NewGuid(), seriesA);
+            sharedSeasonA.PresentationUniqueKey = "merged-series-001";
+            var sharedSeasonB = CreateItem(Guid.NewGuid(), seriesB);
+            sharedSeasonB.PresentationUniqueKey = "merged-series-001";
+            var ownSeason = CreateItem(Guid.NewGuid(), seriesB);
+            ownSeason.PresentationUniqueKey = "merged-series-002";
+
+            context.BaseItems.AddRange(sharedSeasonA, sharedSeasonB, ownSeason);
+            context.SaveChanges();
+        }
+
+        var result = _service.GetChildCountBatch([seriesA, seriesB], null);
+
+        Assert.Equal(2, result[seriesA]);
+        Assert.Equal(2, result[seriesB]);
+    }
+
+    private (User User, Guid SeriesA, Guid SeriesB) SeedMergedSeries(out Guid playedLeafId)
+    {
+        var user = new User("count-test", "provider", "reset");
+        var seriesA = Guid.NewGuid();
+        var seriesB = Guid.NewGuid();
+        var leafA = Guid.NewGuid();
+        var leafB = Guid.NewGuid();
+        playedLeafId = leafA;
+
+        using (var context = CreateDbContext())
+        {
+            context.Users.Add(user);
+
+            foreach (var id in new[] { seriesA, seriesB })
+            {
+                var series = CreateItem(id);
+                series.PresentationUniqueKey = "merged-series";
+                context.BaseItems.Add(series);
+            }
+
+            context.BaseItems.AddRange(CreateLeaf(leafA), CreateLeaf(leafB));
+            context.SaveChanges();
+
+            AddAncestor(context, leafA, seriesA);
+            AddAncestor(context, leafB, seriesB);
+
+            context.UserData.Add(new UserData
+            {
+                ItemId = leafA,
+                UserId = user.Id,
+                CustomDataKey = string.Empty,
+                Played = true,
+                Item = null,
+                User = null
+            });
+
+            context.SaveChanges();
+        }
+
+        return (user, seriesA, seriesB);
+    }
+
+    private static void AddAncestor(JellyfinDbContext context, Guid itemId, Guid parentItemId)
+    {
+        context.AncestorIds.Add(new AncestorId
+        {
+            ItemId = itemId,
+            ParentItemId = parentItemId,
+            Item = null!,
+            ParentItem = null!
+        });
+    }
+
+    private static BaseItemEntity CreateLeaf(Guid id)
+    {
+        return new BaseItemEntity
+        {
+            Id = id,
+            Type = "Episode",
+            IsFolder = false,
+            IsVirtualItem = false,
+            PresentationUniqueKey = id.ToString("N")
+        };
+    }
+
     private static BaseItemEntity CreateItem(Guid id, Guid? parentId = null)
     {
         return new BaseItemEntity