fix: classic playout playlist progress

CHANGELOG.md

@@ -7,6 +7,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Fixed
 - Fix regression from `v26.2.0` that caused channel logo watermarks to be ignored when the logo is a url
   - This affected external logo urls and generated channel logos
+- Maintain collection progress when refreshing a classic playout containing playlists
 
 ## [26.7.0] - 2026-07-27
 ### Added

ErsatzTV.Core.Tests/Fakes/FakeMediaCollectionRepository.cs

@@ -7,13 +7,20 @@ namespace ErsatzTV.Core.Tests.Fakes;
 public class FakeMediaCollectionRepository : IMediaCollectionRepository
 {
     private readonly Map<int, List<MediaItem>> _data;
+    private readonly Map<int, Dictionary<PlaylistItem, List<MediaItem>>> _playlists;
 
-    public FakeMediaCollectionRepository(Map<int, List<MediaItem>> data) => _data = data;
+    public FakeMediaCollectionRepository(
+        Map<int, List<MediaItem>> data,
+        Map<int, Dictionary<PlaylistItem, List<MediaItem>>> playlists = default)
+    {
+        _data = data;
+        _playlists = playlists;
+    }
 
     public Task<Dictionary<PlaylistItem, List<MediaItem>>> GetPlaylistItemMap(
         int playlistId,
         CancellationToken cancellationToken) =>
-        throw new NotSupportedException();
+        _playlists[playlistId].AsTask();
 
     public Task<Dictionary<PlaylistItem, List<MediaItem>>> GetPlaylistItemMap(
         string groupName,
@@ -44,7 +51,8 @@ public class FakeMediaCollectionRepository : IMediaCollectionRepository
 
     public Task<List<MediaItem>> GetRerunCollectionItems(int id, CancellationToken cancellationToken) => throw new NotSupportedException();
     public Task<List<MediaItem>> GetShowItemsByShowGuids(List<string> guids) => throw new NotSupportedException();
-    public Task<List<MediaItem>> GetPlaylistItems(int id, CancellationToken cancellationToken) => throw new NotSupportedException();
+    public Task<List<MediaItem>> GetPlaylistItems(int id, CancellationToken cancellationToken) =>
+        _playlists[id].Values.SelectMany(items => items).DistinctBy(mi => mi.Id).ToList().AsTask();
     public Task<List<Movie>> GetMovie(int id) => throw new NotSupportedException();
     public Task<List<Episode>> GetEpisode(int id) => throw new NotSupportedException();
     public Task<List<MusicVideo>> GetMusicVideo(int id) => throw new NotSupportedException();

ErsatzTV.Core.Tests/Scheduling/ClassicScheduling/PlaylistAnchorRefreshTests.cs

@@ -0,0 +1,160 @@
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Domain.Scheduling;
+using ErsatzTV.Core.Interfaces.Repositories;
+using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling;
+using ErsatzTV.Core.Tests.Fakes;
+using NSubstitute;
+using NUnit.Framework;
+using Shouldly;
+using Testably.Abstractions.Testing;
+
+namespace ErsatzTV.Core.Tests.Scheduling.ClassicScheduling;
+
+// refresh used to re-pick one anchor per collection with a bucket per key column, and there was no
+// bucket for playlists, so every playlist anchor was dropped on every refresh
+[TestFixture]
+public class PlaylistAnchorRefreshTests : PlayoutBuilderTestBase
+{
+    private const int PlaylistId = 1;
+    private const int DaysToBuild = 2;
+
+    [Test]
+    public async Task Refresh_Should_Not_Reset_Playlist_Progress()
+    {
+        // long enough that the playlist cycle can't complete, so the index measures progress directly
+        (PlayoutBuilder builder, Playout playout, PlayoutReferenceData referenceData) =
+            PlaylistTestData(TimeSpan.FromHours(6), itemCount: 300);
+
+        DateTimeOffset start = LocalTime(20);
+
+        for (var hour = 0; hour < 24 * 21; hour++)
+        {
+            await builder.Build(
+                start.AddHours(hour),
+                playout,
+                referenceData,
+                PlayoutBuildMode.Continue,
+                CancellationToken);
+        }
+
+        int before = HeadIndex(playout);
+        before.ShouldBeGreaterThan(0, "the fast forward should have consumed some of the playlist");
+
+        Either<BaseError, PlayoutBuildResult> result = await builder.Build(
+            start.AddDays(21),
+            playout,
+            referenceData,
+            PlayoutBuildMode.Refresh,
+            CancellationToken);
+
+        result.IsRight.ShouldBeTrue();
+
+        // rewinding to the start of today legitimately moves the index back by up to a day; a refresh
+        // that dropped the anchor lands back at the beginning of the playlist
+        int after = HeadIndex(playout);
+        after.ShouldBeGreaterThan(
+            before / 2,
+            $"[tz {TimeZoneInfo.Local.Id}] refresh reset playlist progress (was {before}, now {after})");
+    }
+
+    private static int HeadIndex(Playout playout) =>
+        playout.ProgramScheduleAnchors
+            .Filter(a => a.AnchorDate is null && a.PlaylistId == PlaylistId)
+            .Map(a => a.EnumeratorState.Index)
+            .HeadOrNone()
+            .IfNone(-1);
+
+    private (PlayoutBuilder, Playout, PlayoutReferenceData) PlaylistTestData(TimeSpan itemDuration, int itemCount)
+    {
+        List<MediaItem> mediaItems = Enumerable.Range(1, itemCount)
+            .Map(i => (MediaItem)TestMovie(i, itemDuration, new DateTime(2000 + i, 1, 1)))
+            .ToList();
+
+        var playlistItemMap = new Dictionary<PlaylistItem, List<MediaItem>>
+        {
+            {
+                new PlaylistItem
+                {
+                    Id = 1,
+                    Index = 1,
+                    PlaybackOrder = PlaybackOrder.Chronological,
+                    PlayAll = true,
+                    CollectionType = CollectionType.Collection,
+                    CollectionId = 1
+                },
+                mediaItems
+            }
+        };
+
+        var collectionRepo = new FakeMediaCollectionRepository(
+            Map((1, mediaItems)),
+            Map((PlaylistId, playlistItemMap)));
+
+        IConfigElementRepository configRepo = Substitute.For<IConfigElementRepository>();
+        configRepo
+            .GetValue<int>(
+                Arg.Is<ConfigElementKey>(k => k.Key == ConfigElementKey.PlayoutDaysToBuild.Key),
+                Arg.Any<CancellationToken>())
+            .Returns(Some(DaysToBuild));
+
+        var builder = new PlayoutBuilder(
+            configRepo,
+            collectionRepo,
+            new FakeTelevisionRepository(),
+            Substitute.For<IArtistRepository>(),
+            Substitute.For<IMultiEpisodeShuffleCollectionEnumeratorFactory>(),
+            new MockFileSystem(),
+            Substitute.For<IRerunHelper>(),
+            Logger);
+
+        var schedule = new ProgramSchedule
+        {
+            Id = 1,
+            Items =
+            [
+                new ProgramScheduleItemFlood
+                {
+                    Id = 1,
+                    Index = 1,
+                    CollectionType = CollectionType.Playlist,
+                    PlaylistId = PlaylistId,
+                    StartTime = null,
+                    PlaybackOrder = PlaybackOrder.Chronological
+                }
+            ]
+        };
+
+        var playout = new Playout
+        {
+            Id = 1,
+            ScheduleKind = PlayoutScheduleKind.Classic,
+            ProgramSchedule = schedule,
+            Channel = new Channel(Guid.Empty) { Id = 1, Name = "Test Channel" },
+            Items = [],
+            ProgramScheduleAnchors = [],
+            ProgramScheduleAlternates = [],
+            FillGroupIndices = []
+        };
+
+        var referenceData = new PlayoutReferenceData(
+            playout.Channel,
+            Option<Deco>.None,
+            [],
+            [],
+            schedule,
+            [],
+            [],
+            TimeSpan.Zero);
+
+        return (builder, playout, referenceData);
+    }
+
+    // anchor dates are compared in machine-local time, so the test clock has to be local too; mid-June
+    // to stay clear of DST transitions in every zone
+    private static DateTimeOffset LocalTime(int hour)
+    {
+        var date = new DateTime(2025, 6, 10, 0, 0, 0, DateTimeKind.Unspecified);
+        return new DateTimeOffset(date, TimeZoneInfo.Local.GetUtcOffset(date)) + TimeSpan.FromHours(hour);
+    }
+}

ErsatzTV.Core/Scheduling/CollectionKey.cs

@@ -16,6 +16,22 @@ public class CollectionKey : Record<CollectionKey>
     public string SearchQuery { get; set; }
     public string FakeCollectionKey { get; set; }
 
+    // the inverse of the other factories: every column that makes up an anchor's identity.
+    // keep in sync with PlayoutBuilder.AnchorMatchesCollectionKey
+    public static CollectionKey ForAnchor(PlayoutProgramScheduleAnchor anchor) =>
+        new()
+        {
+            CollectionType = anchor.CollectionType,
+            CollectionId = anchor.CollectionId,
+            MultiCollectionId = anchor.MultiCollectionId,
+            SmartCollectionId = anchor.SmartCollectionId,
+            RerunCollectionId = anchor.RerunCollectionId,
+            MediaItemId = anchor.MediaItemId,
+            PlaylistId = anchor.PlaylistId,
+            SearchQuery = anchor.SearchQuery,
+            FakeCollectionKey = anchor.FakeCollectionKey
+        };
+
     public static CollectionKey ForPlaylistItem(PlaylistItem item) =>
         item.CollectionType switch
         {

ErsatzTV.Core/Scheduling/PlayoutBuilder.cs

@@ -185,67 +185,17 @@ public class PlayoutBuilder : IPlayoutBuilder
 
         // _logger.LogDebug("Remaining anchors: {@Anchors}", playout.ProgramScheduleAnchors);
 
-        var allAnchors = playout.ProgramScheduleAnchors.ToList();
-
-        var collectionIds = playout.ProgramScheduleAnchors.Map(a => Optional(a.CollectionId)).Somes().ToHashSet();
-
-        var multiCollectionIds =
-            playout.ProgramScheduleAnchors.Map(a => Optional(a.MultiCollectionId)).Somes().ToHashSet();
-
-        var smartCollectionIds =
-            playout.ProgramScheduleAnchors.Map(a => Optional(a.SmartCollectionId)).Somes().ToHashSet();
-
-        var searchQueries =
-            playout.ProgramScheduleAnchors.Map(a => Optional(a.SearchQuery)).Somes().ToHashSet();
-
-        var rerunCollectionIds =
-            playout.ProgramScheduleAnchors.Map(a => Optional(a.RerunCollectionId)).Somes().ToHashSet();
-
-        var mediaItemIds = playout.ProgramScheduleAnchors.Map(a => Optional(a.MediaItemId)).Somes().ToHashSet();
+        // only today's checkpoints are left, and at most one per collection key per local date is
+        // ever written, so this should already be one anchor per key; keep the oldest in case an
+        // older database has more. group on the whole key, anything left out is silently dropped,
+        // which is how playlist and fake-collection anchors used to lose their progress
+        List<PlayoutProgramScheduleAnchor> oldestAnchorPerKey = playout.ProgramScheduleAnchors
+            .GroupBy(CollectionKey.ForAnchor)
+            .Map(g => g.MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks))
+            .ToList();
 
         playout.ProgramScheduleAnchors.Clear();
-
-        foreach (int collectionId in collectionIds)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.CollectionId == collectionId)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
-
-        foreach (int multiCollectionId in multiCollectionIds)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.MultiCollectionId == multiCollectionId)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
-
-        foreach (int smartCollectionId in smartCollectionIds)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.SmartCollectionId == smartCollectionId)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
-
-        foreach (string searchQuery in searchQueries)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.SearchQuery == searchQuery)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
-
-        foreach (int rerunCollectionId in rerunCollectionIds)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.RerunCollectionId == rerunCollectionId)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
-
-        foreach (int mediaItemId in mediaItemIds)
-        {
-            PlayoutProgramScheduleAnchor minAnchor = allAnchors.Filter(a => a.MediaItemId == mediaItemId)
-                .MinBy(a => a.AnchorDateOffset.IfNone(DateTimeOffset.MaxValue).Ticks);
-            playout.ProgramScheduleAnchors.Add(minAnchor);
-        }
+        playout.ProgramScheduleAnchors.AddRange(oldestAnchorPerKey);
 
         // _logger.LogDebug("Oldest anchors for each collection: {@Anchors}", playout.ProgramScheduleAnchors);
 
@@ -257,9 +207,11 @@ public class PlayoutBuilder : IPlayoutBuilder
 
         // _logger.LogDebug("Final anchors: {@Anchors}", playout.ProgramScheduleAnchors);
 
+        // rewind to the start of today, so take the earliest rather than whichever comes first
         Option<DateTime> maybeAnchorDate = playout.ProgramScheduleAnchors
             .Map(a => Optional(a.AnchorDate))
             .Somes()
+            .OrderBy(d => d)
             .HeadOrNone();
 
         foreach (DateTime anchorDate in maybeAnchorDate)