refactor yaml playout builder (#1820)

* update changelog * refactor some handlers * refactor skip items instruction * more refactoring
2024-07-27 10:33:21 -05:00
parent 8488fe5d3d
commit e4e4f68eb4
30 changed files with 605 additions and 407 deletions
@@ -42,6 +42,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fix infinite loop caused by impossible schedule (all collection items longer than schedule item duration)
 - Fix selecting audio and subtitle streams with two-letter language codes
 - Fix adding pad filler to content that is less than one minute in duration
+- Generate unique identifier for virtual HDHomeRun tuner by @raknam
+  - This allows a single Plex server to connect to multiple ETV instances

 ### Changed
 - Remove some unnecessary API calls related to media server scanning and paging
@@ -0,0 +1,85 @@
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Interfaces.Repositories;
+using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+
+public class EnumeratorCache(IMediaCollectionRepository mediaCollectionRepository)
+{
+    private readonly Dictionary<string, IMediaCollectionEnumerator> _enumerators = new();
+
+    public System.Collections.Generic.HashSet<string> MissingContentKeys { get; } = [];
+
+    public async Task<Option<IMediaCollectionEnumerator>> GetCachedEnumeratorForContent(
+        YamlPlayoutContext context,
+        string contentKey,
+        CancellationToken cancellationToken)
+    {
+        if (string.IsNullOrWhiteSpace(contentKey))
+        {
+            return Option<IMediaCollectionEnumerator>.None;
+        }
+
+        if (!_enumerators.TryGetValue(contentKey, out IMediaCollectionEnumerator enumerator))
+        {
+            Option<IMediaCollectionEnumerator> maybeEnumerator =
+                await GetEnumeratorForContent(context, contentKey, cancellationToken);
+
+            if (maybeEnumerator.IsNone)
+            {
+                return Option<IMediaCollectionEnumerator>.None;
+            }
+
+            foreach (IMediaCollectionEnumerator e in maybeEnumerator)
+            {
+                enumerator = e;
+                _enumerators.Add(contentKey, enumerator);
+            }
+        }
+
+        return Some(enumerator);
+    }
+
+    private async Task<Option<IMediaCollectionEnumerator>> GetEnumeratorForContent(
+        YamlPlayoutContext context,
+        string contentKey,
+        CancellationToken cancellationToken)
+    {
+        int index = context.Definition.Content.FindIndex(c => c.Key == contentKey);
+        if (index < 0)
+        {
+            return Option<IMediaCollectionEnumerator>.None;
+        }
+
+        List<MediaItem> items = [];
+
+        YamlPlayoutContentItem content = context.Definition.Content[index];
+        switch (content)
+        {
+            case YamlPlayoutContentSearchItem search:
+                items = await mediaCollectionRepository.GetSmartCollectionItems(search.Query);
+                break;
+            case YamlPlayoutContentShowItem show:
+                items = await mediaCollectionRepository.GetShowItemsByShowGuids(
+                    show.Guids.Map(g => $"{g.Source}://{g.Value}").ToList());
+                break;
+        }
+
+        // start at the appropriate place in the enumerator
+        context.ContentIndex.TryGetValue(contentKey, out int enumeratorIndex);
+
+        var state = new CollectionEnumeratorState { Seed = context.Playout.Seed + index, Index = enumeratorIndex };
+        switch (Enum.Parse<PlaybackOrder>(content.Order, true))
+        {
+            case PlaybackOrder.Chronological:
+                return new ChronologicalMediaCollectionEnumerator(items, state);
+            case PlaybackOrder.Shuffle:
+                // TODO: fix this
+                var groupedMediaItems = items.Map(mi => new GroupedMediaItem(mi, null)).ToList();
+                return new ShuffledMediaCollectionEnumerator(groupedMediaItems, state, cancellationToken);
+        }
+
+        return Option<IMediaCollectionEnumerator>.None;
+    }
+}
@@ -0,0 +1,15 @@
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public interface IYamlPlayoutHandler
+{
+    bool Reset { get; }
+
+    Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken);
+}
@@ -0,0 +1,65 @@
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Domain.Filler;
+using ErsatzTV.Core.Extensions;
+using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public abstract class YamlPlayoutContentHandler(EnumeratorCache enumeratorCache) : IYamlPlayoutHandler
+{
+    public bool Reset => false;
+
+    public abstract Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken);
+
+    protected async Task<Option<IMediaCollectionEnumerator>> GetContentEnumerator(
+        YamlPlayoutContext context,
+        string contentKey,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        Option<IMediaCollectionEnumerator> maybeEnumerator = await enumeratorCache.GetCachedEnumeratorForContent(
+            context,
+            contentKey,
+            cancellationToken);
+
+        if (maybeEnumerator.IsNone)
+        {
+            if (!enumeratorCache.MissingContentKeys.Contains(contentKey))
+            {
+                logger.LogWarning("Unable to locate content with key {Key}", contentKey);
+                enumeratorCache.MissingContentKeys.Add(contentKey);
+            }
+        }
+
+        return maybeEnumerator;
+    }
+
+    protected static TimeSpan DurationForMediaItem(MediaItem mediaItem)
+    {
+        if (mediaItem is Image image)
+        {
+            return TimeSpan.FromSeconds(image.ImageMetadata.Head().DurationSeconds ?? Image.DefaultSeconds);
+        }
+
+        MediaVersion version = mediaItem.GetHeadVersion();
+        return version.Duration;
+    }
+
+    protected static FillerKind GetFillerKind(YamlPlayoutInstruction instruction)
+    {
+        if (string.IsNullOrWhiteSpace(instruction.FillerKind))
+        {
+            return FillerKind.None;
+        }
+
+        return Enum.TryParse(instruction.FillerKind, ignoreCase: true, out FillerKind result)
+            ? result
+            : FillerKind.None;
+    }
+}
@@ -0,0 +1,70 @@
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutCountHandler(EnumeratorCache enumeratorCache) : YamlPlayoutContentHandler(enumeratorCache)
+{
+    public override async Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutCountInstruction count)
+        {
+            return false;
+        }
+
+        Option<IMediaCollectionEnumerator> maybeEnumerator = await GetContentEnumerator(
+            context,
+            instruction.Content,
+            logger,
+            cancellationToken);
+
+        foreach (IMediaCollectionEnumerator enumerator in maybeEnumerator)
+        {
+            for (var i = 0; i < count.Count; i++)
+            {
+                foreach (MediaItem mediaItem in enumerator.Current)
+                {
+                    TimeSpan itemDuration = DurationForMediaItem(mediaItem);
+
+                    // create a playout item
+                    var playoutItem = new PlayoutItem
+                    {
+                        MediaItemId = mediaItem.Id,
+                        Start = context.CurrentTime.UtcDateTime,
+                        Finish = context.CurrentTime.UtcDateTime + itemDuration,
+                        InPoint = TimeSpan.Zero,
+                        OutPoint = itemDuration,
+                        FillerKind = GetFillerKind(count),
+                        //CustomTitle = scheduleItem.CustomTitle,
+                        //WatermarkId = scheduleItem.WatermarkId,
+                        //PreferredAudioLanguageCode = scheduleItem.PreferredAudioLanguageCode,
+                        //PreferredAudioTitle = scheduleItem.PreferredAudioTitle,
+                        //PreferredSubtitleLanguageCode = scheduleItem.PreferredSubtitleLanguageCode,
+                        //SubtitleMode = scheduleItem.SubtitleMode
+                        GuideGroup = context.GuideGroup
+                        //GuideStart = effectiveBlock.Start.UtcDateTime,
+                        //GuideFinish = blockFinish.UtcDateTime,
+                        //BlockKey = JsonConvert.SerializeObject(effectiveBlock.BlockKey),
+                        //CollectionKey = JsonConvert.SerializeObject(collectionKey, JsonSettings),
+                        //CollectionEtag = collectionEtags[collectionKey]
+                    };
+
+                    context.Playout.Items.Add(playoutItem);
+
+                    context.CurrentTime += itemDuration;
+                    enumerator.MoveNext();
+                }
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+}
@@ -1,53 +1,73 @@
 using ErsatzTV.Core.Domain;
 using ErsatzTV.Core.Domain.Filler;
 using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
 using TimeSpanParserUtil;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;

-public class YamlPlayoutSchedulerDuration : YamlPlayoutScheduler
+public class YamlPlayoutDurationHandler(EnumeratorCache enumeratorCache) : YamlPlayoutContentHandler(enumeratorCache)
 {
-    public static DateTimeOffset Schedule(
-        Playout playout,
-        DateTimeOffset currentTime,
-        int guideGroup,
-        YamlPlayoutDurationInstruction duration,
-        IMediaCollectionEnumerator enumerator,
-        Option<IMediaCollectionEnumerator> fallbackEnumerator)
+    public override async Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
    {
+        if (instruction is not YamlPlayoutDurationInstruction duration)
+        {
+            return false;
+        }
+
        // TODO: move to up-front validation somewhere
        if (!TimeSpanParser.TryParse(duration.Duration, out TimeSpan timeSpan))
        {
-            return currentTime;
+            return false;
        }

-        DateTimeOffset targetTime = currentTime.Add(timeSpan);
+        DateTimeOffset targetTime = context.CurrentTime.Add(timeSpan);

-        return Schedule(
-            playout,
-            currentTime,
-            targetTime,
-            duration.DiscardAttempts,
-            duration.Trim,
-            GetFillerKind(duration),
-            guideGroup,
-            enumerator,
-            fallbackEnumerator);
+        Option<IMediaCollectionEnumerator> maybeEnumerator = await GetContentEnumerator(
+            context,
+            instruction.Content,
+            logger,
+            cancellationToken);
+
+        Option<IMediaCollectionEnumerator> fallbackEnumerator = await GetContentEnumerator(
+            context,
+            duration.Fallback,
+            logger,
+            cancellationToken);
+
+        foreach (IMediaCollectionEnumerator enumerator in maybeEnumerator)
+        {
+            context.CurrentTime = Schedule(
+                context,
+                targetTime,
+                duration.DiscardAttempts,
+                duration.Trim,
+                GetFillerKind(duration),
+                enumerator,
+                fallbackEnumerator);
+
+            return true;
+        }
+
+        return false;
    }

    protected static DateTimeOffset Schedule(
-        Playout playout,
-        DateTimeOffset currentTime,
+        YamlPlayoutContext context,
        DateTimeOffset targetTime,
        int discardAttempts,
        bool trim,
        FillerKind fillerKind,
-        int guideGroup,
        IMediaCollectionEnumerator enumerator,
        Option<IMediaCollectionEnumerator> fallbackEnumerator)
    {
        bool done = false;
-        TimeSpan remainingToFill = targetTime - currentTime;
+        TimeSpan remainingToFill = targetTime - context.CurrentTime;
        while (!done && enumerator.Current.IsSome && remainingToFill > TimeSpan.Zero)
        {
            foreach (MediaItem mediaItem in enumerator.Current)
@@ -57,11 +77,11 @@ public class YamlPlayoutSchedulerDuration : YamlPlayoutScheduler
                var playoutItem = new PlayoutItem
                {
                    MediaItemId = mediaItem.Id,
-                    Start = currentTime.UtcDateTime,
-                    Finish = currentTime.UtcDateTime + itemDuration,
+                    Start = context.CurrentTime.UtcDateTime,
+                    Finish = context.CurrentTime.UtcDateTime + itemDuration,
                    InPoint = TimeSpan.Zero,
                    OutPoint = itemDuration,
-                    GuideGroup = guideGroup,
+                    GuideGroup = context.GuideGroup,
                    FillerKind = fillerKind
                    //DisableWatermarks = !allowWatermarks
                };
@@ -69,9 +89,9 @@ public class YamlPlayoutSchedulerDuration : YamlPlayoutScheduler
                if (remainingToFill - itemDuration >= TimeSpan.Zero)
                {
                    remainingToFill -= itemDuration;
-                    currentTime += itemDuration;
+                    context.CurrentTime += itemDuration;

-                    playout.Items.Add(playoutItem);
+                    context.Playout.Items.Add(playoutItem);
                    enumerator.MoveNext();
                }
                else if (discardAttempts > 0)
@@ -84,12 +104,12 @@ public class YamlPlayoutSchedulerDuration : YamlPlayoutScheduler
                {
                    // trim item to exactly fit
                    remainingToFill = TimeSpan.Zero;
-                    currentTime = targetTime;
+                    context.CurrentTime = targetTime;

                    playoutItem.Finish = targetTime.UtcDateTime;
                    playoutItem.OutPoint = playoutItem.Finish - playoutItem.Start;

-                    playout.Items.Add(playoutItem);
+                    context.Playout.Items.Add(playoutItem);
                    enumerator.MoveNext();
                }
                else if (fallbackEnumerator.IsSome)
@@ -106,7 +126,7 @@ public class YamlPlayoutSchedulerDuration : YamlPlayoutScheduler
                            playoutItem.Finish = targetTime.UtcDateTime;
                            playoutItem.FillerKind = FillerKind.Fallback;

-                            playout.Items.Add(playoutItem);
+                            context.Playout.Items.Add(playoutItem);
                            fallback.MoveNext();
                        }
                    }
@@ -0,0 +1,24 @@
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutNewEpgGroupHandler : IYamlPlayoutHandler
+{
+    public bool Reset => false;
+
+    public Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutNewEpgGroupInstruction)
+        {
+            return Task.FromResult(false);
+        }
+
+        context.GuideGroup *= -1;
+        return Task.FromResult(true);
+    }
+}
@@ -0,0 +1,68 @@
+using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutPadToNextHandler(EnumeratorCache enumeratorCache) : YamlPlayoutDurationHandler(enumeratorCache)
+{
+    public override async Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutPadToNextInstruction padToNext)
+        {
+            return false;
+        }
+
+        int currentMinute = context.CurrentTime.Minute;
+
+        int targetMinute = (currentMinute + padToNext.PadToNext - 1) / padToNext.PadToNext * padToNext.PadToNext;
+
+        DateTimeOffset almostTargetTime =
+            context.CurrentTime - TimeSpan.FromMinutes(currentMinute) + TimeSpan.FromMinutes(targetMinute);
+
+        var targetTime = new DateTimeOffset(
+            almostTargetTime.Year,
+            almostTargetTime.Month,
+            almostTargetTime.Day,
+            almostTargetTime.Hour,
+            almostTargetTime.Minute,
+            0,
+            almostTargetTime.Offset);
+
+        // ensure filler works for content less than one minute
+        if (targetTime <= context.CurrentTime)
+            targetTime = targetTime.AddMinutes(padToNext.PadToNext);
+
+        Option<IMediaCollectionEnumerator> maybeEnumerator = await GetContentEnumerator(
+            context,
+            instruction.Content,
+            logger,
+            cancellationToken);
+
+        Option<IMediaCollectionEnumerator> fallbackEnumerator = await GetContentEnumerator(
+            context,
+            padToNext.Fallback,
+            logger,
+            cancellationToken);
+
+        foreach (IMediaCollectionEnumerator enumerator in maybeEnumerator)
+        {
+            context.CurrentTime = Schedule(
+                context,
+                targetTime,
+                padToNext.DiscardAttempts,
+                padToNext.Trim,
+                GetFillerKind(padToNext),
+                enumerator,
+                fallbackEnumerator);
+
+            return true;
+        }
+
+        return false;
+    }
+}
@@ -0,0 +1,33 @@
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutRepeatHandler : IYamlPlayoutHandler
+{
+    private int _itemsSinceLastRepeat;
+
+    public bool Reset => false;
+
+    public Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutRepeatInstruction)
+        {
+            return Task.FromResult(false);
+        }
+
+        if (_itemsSinceLastRepeat == context.Playout.Items.Count)
+        {
+            logger.LogWarning("Repeat encountered without adding any playout items; aborting");
+            return Task.FromResult(false);
+        }
+
+        _itemsSinceLastRepeat = context.Playout.Items.Count;
+        context.InstructionIndex = 0;
+        return Task.FromResult(true);
+    }
+}
@@ -0,0 +1,33 @@
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutSkipItemsHandler : IYamlPlayoutHandler
+{
+    public bool Reset => true;
+
+    public Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutSkipItemsInstruction skipItems)
+        {
+            return Task.FromResult(false);
+        }
+
+        if (context.ContentIndex.TryGetValue(skipItems.Content, out int value))
+        {
+            value += skipItems.SkipItems;
+        }
+        else
+        {
+            value = skipItems.SkipItems;
+        }
+
+        context.ContentIndex[skipItems.Content] = value;
+        return Task.FromResult(true);
+    }
+}
@@ -0,0 +1,47 @@
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+using Microsoft.Extensions.Logging;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+
+public class YamlPlayoutWaitUntilHandler : IYamlPlayoutHandler
+{
+    public bool Reset => true;
+
+    public Task<bool> Handle(
+        YamlPlayoutContext context,
+        YamlPlayoutInstruction instruction,
+        ILogger<YamlPlayoutBuilder> logger,
+        CancellationToken cancellationToken)
+    {
+        if (instruction is not YamlPlayoutWaitUntilInstruction waitUntil)
+        {
+            return Task.FromResult(false);
+        }
+
+        DateTimeOffset currentTime = context.CurrentTime;
+
+        if (TimeOnly.TryParse(waitUntil.WaitUntil, out TimeOnly result))
+        {
+            var dayOnly = DateOnly.FromDateTime(currentTime.LocalDateTime);
+            var timeOnly = TimeOnly.FromDateTime(currentTime.LocalDateTime);
+
+            if (timeOnly > result)
+            {
+                if (waitUntil.Tomorrow)
+                {
+                    // this is wrong when offset changes
+                    dayOnly = dayOnly.AddDays(1);
+                    currentTime = new DateTimeOffset(dayOnly, result, currentTime.Offset);
+                }
+            }
+            else
+            {
+                // this is wrong when offset changes
+                currentTime = new DateTimeOffset(dayOnly, result, currentTime.Offset);
+            }
+        }
+
+        context.CurrentTime = currentTime;
+        return Task.FromResult(true);
+    }
+}
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutContentGuid
 {
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutContentItem
 {
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutContentSearchItem : YamlPlayoutContentItem
 {
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutContentShowItem : YamlPlayoutContentItem
 {
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutCountInstruction : YamlPlayoutInstruction
 {
@@ -1,4 +1,4 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutDefinition
 {
@@ -1,6 +1,6 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutDurationInstruction : YamlPlayoutInstruction
 {
@@ -1,9 +1,11 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutInstruction
 {
+    public virtual bool ChangesIndex => false;
+
    public string Content { get; set; }

    [YamlMember(Alias = "filler_kind", ApplyNamingConventions = false)]
@@ -1,6 +1,6 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutNewEpgGroupInstruction : YamlPlayoutInstruction
 {
@@ -1,6 +1,6 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutPadToNextInstruction : YamlPlayoutInstruction
 {
@@ -1,6 +1,8 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutRepeatInstruction : YamlPlayoutInstruction
 {
+    public override bool ChangesIndex => true;
+
    public bool Repeat { get; set; }
 }
@@ -1,6 +1,6 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutSkipItemsInstruction : YamlPlayoutInstruction
 {
@@ -1,6 +1,6 @@
 using YamlDotNet.Serialization;

-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+namespace ErsatzTV.Core.Scheduling.YamlScheduling.Models;

 public class YamlPlayoutWaitUntilInstruction : YamlPlayoutInstruction
 {
@@ -2,6 +2,8 @@ using ErsatzTV.Core.Domain;
 using ErsatzTV.Core.Interfaces.Metadata;
 using ErsatzTV.Core.Interfaces.Repositories;
 using ErsatzTV.Core.Interfaces.Scheduling;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Handlers;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
 using Microsoft.Extensions.Logging;
 using YamlDotNet.Serialization;
 using YamlDotNet.Serialization.NamingConventions;
@@ -35,263 +37,112 @@ public class YamlPlayoutBuilder(
            return playout;
        }

-        YamlPlayoutInitialState initialState = HandleResetActions(playout, playoutDefinition, start);
-
-        DateTimeOffset currentTime = initialState.CurrentTime;
-
        // load content and content enumerators on demand
-        Dictionary<string, IMediaCollectionEnumerator> enumerators = new();
-        System.Collections.Generic.HashSet<string> missingContentKeys = [];
+        Dictionary<YamlPlayoutInstruction, IYamlPlayoutHandler> handlers = new();
+        var enumeratorCache = new EnumeratorCache(mediaCollectionRepository);

-        int itemsAfterRepeat = playout.Items.Count;
-        int guideGroup = 1;
-        var index = 0;
-        while (currentTime < finish)
+        var context = new YamlPlayoutContext(playout, playoutDefinition)
        {
-            if (index >= playoutDefinition.Playout.Count)
+            CurrentTime = start,
+            GuideGroup = 1,
+            InstructionIndex = 0
+        };
+
+        // ReSharper disable once ConditionIsAlwaysTrueOrFalse
+        if (mode is PlayoutBuildMode.Reset)
+        {
+            context.Playout.Seed = new Random().Next();
+            context.Playout.Items.Clear();
+
+            // handle all on-reset instructions
+            foreach (YamlPlayoutInstruction instruction in playoutDefinition.Reset)
+            {
+                Option<IYamlPlayoutHandler> maybeHandler = GetHandlerForInstruction(
+                    handlers,
+                    enumeratorCache,
+                    instruction);
+
+                foreach (IYamlPlayoutHandler handler in maybeHandler)
+                {
+                    if (!handler.Reset)
+                    {
+                        logger.LogInformation(
+                            "Skipping unsupported reset instruction {Instruction}",
+                            instruction.GetType().Name);
+                    }
+                    else
+                    {
+                        await handler.Handle(context, instruction, logger, cancellationToken);
+                    }
+                }
+            }
+        }
+
+        // handle all playout instructions
+        while (context.CurrentTime < finish)
+        {
+            if (context.InstructionIndex >= playoutDefinition.Playout.Count)
            {
                logger.LogInformation("Reached the end of the YAML playout definition; stopping");
                break;
            }

-            YamlPlayoutInstruction playoutItem = playoutDefinition.Playout[index];
+            YamlPlayoutInstruction instruction = playoutDefinition.Playout[context.InstructionIndex];
+            Option<IYamlPlayoutHandler> maybeHandler = GetHandlerForInstruction(handlers, enumeratorCache, instruction);

-            // handle instructions that don't reference content
-            switch (playoutItem)
+            foreach (IYamlPlayoutHandler handler in maybeHandler)
            {
-                case YamlPlayoutWaitUntilInstruction waitUntil:
-                    currentTime = HandleWaitUntil(currentTime, waitUntil);
-                    index++;
-                    continue;
-                case YamlPlayoutRepeatInstruction:
-                    // repeat resets index into YAML playout
-                    index = 0;
-                    if (playout.Items.Count == itemsAfterRepeat)
-                    {
-                        logger.LogWarning("Repeat encountered without adding any playout items; aborting");
-                        break;
-                    }
-
-                    itemsAfterRepeat = playout.Items.Count;
-                    continue;
-                case YamlPlayoutNewEpgGroupInstruction:
-                    guideGroup *= -1;
-                    index++;
-                    continue;
-            }
-
-            Option<IMediaCollectionEnumerator> maybeEnumerator = await GetCachedEnumeratorForContent(
-                initialState,
-                playout,
-                playoutDefinition,
-                enumerators,
-                playoutItem.Content,
-                cancellationToken);
-
-            if (maybeEnumerator.IsNone)
-            {
-                if (!missingContentKeys.Contains(playoutItem.Content))
+                if (!await handler.Handle(context, instruction, logger, cancellationToken))
                {
-                    logger.LogWarning("Unable to locate content with key {Key}", playoutItem.Content);
-                    missingContentKeys.Add(playoutItem.Content);
+                    logger.LogInformation("YAML playout instruction handler failed");
                }
            }

-            foreach (IMediaCollectionEnumerator enumerator in maybeEnumerator)
+            if (!instruction.ChangesIndex)
            {
-                switch (playoutItem)
-                {
-                    case YamlPlayoutCountInstruction count:
-                        currentTime = YamlPlayoutSchedulerCount.Schedule(playout, currentTime, guideGroup, count, enumerator);
-                        break;
-                    case YamlPlayoutDurationInstruction duration:
-                        Option<IMediaCollectionEnumerator> durationFallbackEnumerator = await GetCachedEnumeratorForContent(
-                            initialState,
-                            playout,
-                            playoutDefinition,
-                            enumerators,
-                            duration.Fallback,
-                            cancellationToken);
-                        currentTime = YamlPlayoutSchedulerDuration.Schedule(
-                            playout,
-                            currentTime,
-                            guideGroup,
-                            duration,
-                            enumerator,
-                            durationFallbackEnumerator);
-                        break;
-                    case YamlPlayoutPadToNextInstruction padToNext:
-                        Option<IMediaCollectionEnumerator> fallbackEnumerator = await GetCachedEnumeratorForContent(
-                            initialState,
-                            playout,
-                            playoutDefinition,
-                            enumerators,
-                            padToNext.Fallback,
-                            cancellationToken);
-                        currentTime = YamlPlayoutSchedulerPadToNext.Schedule(
-                            playout,
-                            currentTime,
-                            guideGroup,
-                            padToNext,
-                            enumerator,
-                            fallbackEnumerator);
-                        break;
-                }
+                context.InstructionIndex++;
            }
-
-            index++;
        }

        return playout;
    }

-    private YamlPlayoutInitialState HandleResetActions(
-        Playout playout,
-        YamlPlayoutDefinition playoutDefinition,
-        DateTimeOffset currentTime)
-    {
-        var result = new YamlPlayoutInitialState { CurrentTime = currentTime };
-
-        // these are only for reset
-        playout.Seed = new Random().Next();
-        playout.Items.Clear();
-
-        foreach (YamlPlayoutInstruction instruction in playoutDefinition.Reset)
-        {
-            switch (instruction)
-            {
-                case YamlPlayoutWaitUntilInstruction waitUntil:
-                    result.CurrentTime = HandleWaitUntil(result.CurrentTime, waitUntil);
-                    break;
-                case YamlPlayoutSkipItemsInstruction skipItems:
-                    if (result.ContentIndex.TryGetValue(skipItems.Content, out int value))
-                    {
-                        value += skipItems.SkipItems;
-                    }
-                    else
-                    {
-                        value = skipItems.SkipItems;
-                    }
-
-                    result.ContentIndex[skipItems.Content] = value;
-                    break;
-                default:
-                    logger.LogInformation(
-                        "Skipping unsupported reset instruction {Instruction}",
-                        instruction.GetType().Name);
-                    break;
-            }
-        }
-
-        return result;
-    }
-
-    private static DateTimeOffset HandleWaitUntil(DateTimeOffset currentTime, YamlPlayoutWaitUntilInstruction waitUntil)
-    {
-        if (TimeOnly.TryParse(waitUntil.WaitUntil, out TimeOnly result))
-        {
-            var dayOnly = DateOnly.FromDateTime(currentTime.LocalDateTime);
-            var timeOnly = TimeOnly.FromDateTime(currentTime.LocalDateTime);
-
-            if (timeOnly > result)
-            {
-                if (waitUntil.Tomorrow)
-                {
-                    // this is wrong when offset changes
-                    dayOnly = dayOnly.AddDays(1);
-                    currentTime = new DateTimeOffset(dayOnly, result, currentTime.Offset);
-                }
-            }
-            else
-            {
-                // this is wrong when offset changes
-                currentTime = new DateTimeOffset(dayOnly, result, currentTime.Offset);
-            }
-        }
-
-        return currentTime;
-    }
-
    private async Task<int> GetDaysToBuild() =>
        await configElementRepository
            .GetValue<int>(ConfigElementKey.PlayoutDaysToBuild)
            .IfNoneAsync(2);

-    private async Task<Option<IMediaCollectionEnumerator>> GetCachedEnumeratorForContent(
-        YamlPlayoutInitialState initialState,
-        Playout playout,
-        YamlPlayoutDefinition playoutDefinition,
-        Dictionary<string, IMediaCollectionEnumerator> enumerators,
-        string contentKey,
-        CancellationToken cancellationToken)
+    private static Option<IYamlPlayoutHandler> GetHandlerForInstruction(
+        Dictionary<YamlPlayoutInstruction, IYamlPlayoutHandler> handlers,
+        EnumeratorCache enumeratorCache,
+        YamlPlayoutInstruction instruction)
    {
-        if (string.IsNullOrWhiteSpace(contentKey))
+        if (handlers.TryGetValue(instruction, out IYamlPlayoutHandler handler))
        {
-            return Option<IMediaCollectionEnumerator>.None;
+            return Optional(handler);
        }

-        if (!enumerators.TryGetValue(contentKey, out IMediaCollectionEnumerator enumerator))
+        handler = instruction switch
        {
-            Option<IMediaCollectionEnumerator> maybeEnumerator =
-                await GetEnumeratorForContent(initialState, playout, contentKey, playoutDefinition, cancellationToken);
+            YamlPlayoutRepeatInstruction => new YamlPlayoutRepeatHandler(),
+            YamlPlayoutWaitUntilInstruction => new YamlPlayoutWaitUntilHandler(),
+            YamlPlayoutNewEpgGroupInstruction => new YamlPlayoutNewEpgGroupHandler(),
+            YamlPlayoutSkipItemsInstruction => new YamlPlayoutSkipItemsHandler(),

-            if (maybeEnumerator.IsNone)
-            {
-                return Option<IMediaCollectionEnumerator>.None;
-            }
+            // content handlers
+            YamlPlayoutCountInstruction => new YamlPlayoutCountHandler(enumeratorCache),
+            YamlPlayoutDurationInstruction => new YamlPlayoutDurationHandler(enumeratorCache),
+            YamlPlayoutPadToNextInstruction => new YamlPlayoutPadToNextHandler(enumeratorCache),

-            foreach (IMediaCollectionEnumerator e in maybeEnumerator)
-            {
-                enumerator = e;
-                enumerators.Add(contentKey, enumerator);
-            }
+            _ => null
+        };
+
+        if (handler != null)
+        {
+            handlers.Add(instruction, handler);
        }

-        return Some(enumerator);
-    }
-
-    private async Task<Option<IMediaCollectionEnumerator>> GetEnumeratorForContent(
-        YamlPlayoutInitialState initialState,
-        Playout playout,
-        string contentKey,
-        YamlPlayoutDefinition playoutDefinition,
-        CancellationToken cancellationToken)
-    {
-        int index = playoutDefinition.Content.FindIndex(c => c.Key == contentKey);
-        if (index < 0)
-        {
-            return Option<IMediaCollectionEnumerator>.None;
-        }
-
-        List<MediaItem> items = [];
-
-        YamlPlayoutContentItem content = playoutDefinition.Content[index];
-        switch (content)
-        {
-            case YamlPlayoutContentSearchItem search:
-                items = await mediaCollectionRepository.GetSmartCollectionItems(search.Query);
-                break;
-            case YamlPlayoutContentShowItem show:
-                items = await mediaCollectionRepository.GetShowItemsByShowGuids(
-                    show.Guids.Map(g => $"{g.Source}://{g.Value}").ToList());
-                break;
-        }
-
-        // start at the appropriate place in the enumerator
-        initialState.ContentIndex.TryGetValue(contentKey, out int enumeratorIndex);
-
-        var state = new CollectionEnumeratorState { Seed = playout.Seed + index, Index = enumeratorIndex };
-        switch (Enum.Parse<PlaybackOrder>(content.Order, true))
-        {
-            case PlaybackOrder.Chronological:
-                return new ChronologicalMediaCollectionEnumerator(items, state);
-            case PlaybackOrder.Shuffle:
-                // TODO: fix this
-                var groupedMediaItems = items.Map(mi => new GroupedMediaItem(mi, null)).ToList();
-                return new ShuffledMediaCollectionEnumerator(groupedMediaItems, state, cancellationToken);
-        }
-
-        return Option<IMediaCollectionEnumerator>.None;
+        return Optional(handler);
    }

    private static async Task<YamlPlayoutDefinition> LoadYamlDefinition(Playout playout, CancellationToken cancellationToken)
@@ -0,0 +1,20 @@
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Scheduling.YamlScheduling.Models;
+
+namespace ErsatzTV.Core.Scheduling.YamlScheduling;
+
+public class YamlPlayoutContext(Playout playout, YamlPlayoutDefinition definition)
+{
+    public Playout Playout { get; } = playout;
+
+    public YamlPlayoutDefinition Definition { get; } = definition;
+
+    public DateTimeOffset CurrentTime { get; set; }
+
+    public int InstructionIndex { get; set; }
+
+    public int GuideGroup { get; set; }
+
+    // only used for initial state (skip items)
+    public Dictionary<string, int> ContentIndex { get; } = [];
+}
@@ -1,8 +0,0 @@
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
-
-public class YamlPlayoutInitialState
-{
-    public DateTimeOffset CurrentTime { get; set; }
-
-    public Dictionary<string, int> ContentIndex { get; } = [];
-}
@@ -1,31 +0,0 @@
-using ErsatzTV.Core.Domain;
-using ErsatzTV.Core.Domain.Filler;
-using ErsatzTV.Core.Extensions;
-
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
-
-public abstract class YamlPlayoutScheduler
-{
-    protected static TimeSpan DurationForMediaItem(MediaItem mediaItem)
-    {
-        if (mediaItem is Image image)
-        {
-            return TimeSpan.FromSeconds(image.ImageMetadata.Head().DurationSeconds ?? Image.DefaultSeconds);
-        }
-
-        MediaVersion version = mediaItem.GetHeadVersion();
-        return version.Duration;
-    }
-
-    protected static FillerKind GetFillerKind(YamlPlayoutInstruction instruction)
-    {
-        if (string.IsNullOrWhiteSpace(instruction.FillerKind))
-        {
-            return FillerKind.None;
-        }
-
-        return Enum.TryParse(instruction.FillerKind, ignoreCase: true, out FillerKind result)
-            ? result
-            : FillerKind.None;
-    }
-}
@@ -1,53 +0,0 @@
-using ErsatzTV.Core.Domain;
-using ErsatzTV.Core.Interfaces.Scheduling;
-
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
-
-public class YamlPlayoutSchedulerCount : YamlPlayoutScheduler
-{
-    public static DateTimeOffset Schedule(
-        Playout playout,
-        DateTimeOffset currentTime,
-        int guideGroup,
-        YamlPlayoutCountInstruction count,
-        IMediaCollectionEnumerator enumerator)
-    {
-        for (int i = 0; i < count.Count; i++)
-        {
-            foreach (MediaItem mediaItem in enumerator.Current)
-            {
-                TimeSpan itemDuration = DurationForMediaItem(mediaItem);
-
-                // create a playout item
-                var playoutItem = new PlayoutItem
-                {
-                    MediaItemId = mediaItem.Id,
-                    Start = currentTime.UtcDateTime,
-                    Finish = currentTime.UtcDateTime + itemDuration,
-                    InPoint = TimeSpan.Zero,
-                    OutPoint = itemDuration,
-                    FillerKind = GetFillerKind(count),
-                    //CustomTitle = scheduleItem.CustomTitle,
-                    //WatermarkId = scheduleItem.WatermarkId,
-                    //PreferredAudioLanguageCode = scheduleItem.PreferredAudioLanguageCode,
-                    //PreferredAudioTitle = scheduleItem.PreferredAudioTitle,
-                    //PreferredSubtitleLanguageCode = scheduleItem.PreferredSubtitleLanguageCode,
-                    //SubtitleMode = scheduleItem.SubtitleMode
-                    GuideGroup = guideGroup
-                    //GuideStart = effectiveBlock.Start.UtcDateTime,
-                    //GuideFinish = blockFinish.UtcDateTime,
-                    //BlockKey = JsonConvert.SerializeObject(effectiveBlock.BlockKey),
-                    //CollectionKey = JsonConvert.SerializeObject(collectionKey, JsonSettings),
-                    //CollectionEtag = collectionEtags[collectionKey]
-                };
-
-                playout.Items.Add(playoutItem);
-
-                currentTime += itemDuration;
-                enumerator.MoveNext();
-            }
-        }
-
-        return currentTime;
-    }
-}
@@ -1,47 +0,0 @@
-using ErsatzTV.Core.Domain;
-using ErsatzTV.Core.Interfaces.Scheduling;
-
-namespace ErsatzTV.Core.Scheduling.YamlScheduling;
-
-public class YamlPlayoutSchedulerPadToNext : YamlPlayoutSchedulerDuration
-{
-    public static DateTimeOffset Schedule(
-        Playout playout,
-        DateTimeOffset currentTime,
-        int guideGroup,
-        YamlPlayoutPadToNextInstruction padToNext,
-        IMediaCollectionEnumerator enumerator,
-        Option<IMediaCollectionEnumerator> fallbackEnumerator)
-    {
-        int currentMinute = currentTime.Minute;
-
-        int targetMinute = (currentMinute + padToNext.PadToNext - 1) / padToNext.PadToNext * padToNext.PadToNext;
-
-        DateTimeOffset almostTargetTime =
-            currentTime - TimeSpan.FromMinutes(currentMinute) + TimeSpan.FromMinutes(targetMinute);
-
-        var targetTime = new DateTimeOffset(
-            almostTargetTime.Year,
-            almostTargetTime.Month,
-            almostTargetTime.Day,
-            almostTargetTime.Hour,
-            almostTargetTime.Minute,
-            0,
-            almostTargetTime.Offset);
-
-        // ensure filler works for content less than one minute
-        if (targetTime <= currentTime)
-            targetTime = targetTime.AddMinutes(padToNext.PadToNext);
-
-        return Schedule(
-            playout,
-            currentTime,
-            targetTime,
-            padToNext.DiscardAttempts,
-            padToNext.Trim,
-            GetFillerKind(padToNext),
-            guideGroup,
-            enumerator,
-            fallbackEnumerator);
-    }
-}