custom collection playback order (#64)

* add custom index to collection items

* add custom collection order to ui

* cleanup

ErsatzTV.Application/MediaCards/CollectionCardResultsViewModel.cs

@@ -7,5 +7,8 @@ namespace ErsatzTV.Application.MediaCards
         List<MovieCardViewModel> MovieCards,
         List<TelevisionShowCardViewModel> ShowCards,
         List<TelevisionSeasonCardViewModel> SeasonCards,
-        List<TelevisionEpisodeCardViewModel> EpisodeCards);
+        List<TelevisionEpisodeCardViewModel> EpisodeCards)
+    {
+        public bool UseCustomPlaybackOrder { get; set; }
+    }
 }

ErsatzTV.Application/MediaCards/Mapper.cs

@@ -52,11 +52,20 @@ namespace ErsatzTV.Application.MediaCards
             ProjectToViewModel(Collection collection) =>
             new(
                 collection.Name,
-                collection.MediaItems.OfType<Movie>().Map(m => ProjectToViewModel(m.MovieMetadata.Head())).ToList(),
+                collection.MediaItems.OfType<Movie>().Map(
+                    m => ProjectToViewModel(m.MovieMetadata.Head()) with
+                    {
+                        CustomIndex = GetCustomIndex(collection, m.Id)
+                    }).ToList(),
                 collection.MediaItems.OfType<Show>().Map(s => ProjectToViewModel(s.ShowMetadata.Head())).ToList(),
                 collection.MediaItems.OfType<Season>().Map(ProjectToViewModel).ToList(),
                 collection.MediaItems.OfType<Episode>().Map(e => ProjectToViewModel(e.EpisodeMetadata.Head()))
-                    .ToList());
+                    .ToList()) { UseCustomPlaybackOrder = collection.UseCustomPlaybackOrder };
+
+        private static int GetCustomIndex(Collection collection, int mediaItemId) =>
+            Optional(collection.CollectionItems.Find(ci => ci.MediaItemId == mediaItemId))
+                .Map(ci => ci.CustomIndex ?? 0)
+                .IfNone(0);
 
         internal static SearchCardResultsViewModel ProjectToSearchResults(List<MediaItem> items) =>
             new(

ErsatzTV.Application/MediaCards/MediaCardViewModel.cs

@@ -1,4 +1,4 @@
 namespace ErsatzTV.Application.MediaCards
 {
-    public record MediaCardViewModel(string Title, string Subtitle, string SortTitle, string Poster);
+    public record MediaCardViewModel(int MediaItemId, string Title, string Subtitle, string SortTitle, string Poster);
 }

ErsatzTV.Application/MediaCards/MovieCardViewModel.cs

@@ -2,10 +2,12 @@
 {
     public record MovieCardViewModel
         (int MovieId, string Title, string Subtitle, string SortTitle, string Poster) : MediaCardViewModel(
+            MovieId,
             Title,
             Subtitle,
             SortTitle,
             Poster)
     {
+        public int CustomIndex { get; set; }
     }
 }

ErsatzTV.Application/MediaCards/TelevisionEpisodeCardViewModel.cs

@@ -13,6 +13,7 @@ namespace ErsatzTV.Application.MediaCards
         string Title,
         string Plot,
         string Poster) : MediaCardViewModel(
+        EpisodeId,
         Title,
         $"Episode {Episode}",
         $"Episode {Episode}",

ErsatzTV.Application/MediaCards/TelevisionSeasonCardViewModel.cs

@@ -10,6 +10,7 @@
         string SortTitle,
         string Poster,
         string Placeholder) : MediaCardViewModel(
+        TelevisionSeasonId,
         Title,
         Subtitle,
         SortTitle,

ErsatzTV.Application/MediaCards/TelevisionShowCardViewModel.cs

@@ -2,6 +2,7 @@
 {
     public record TelevisionShowCardViewModel
         (int TelevisionShowId, string Title, string Subtitle, string SortTitle, string Poster) : MediaCardViewModel(
+            TelevisionShowId,
             Title,
             Subtitle,
             SortTitle,

ErsatzTV.Application/MediaCollections/Commands/UpdateCollection.cs

@@ -1,8 +1,12 @@
 using ErsatzTV.Core;
 using LanguageExt;
+using static LanguageExt.Prelude;
 
 namespace ErsatzTV.Application.MediaCollections.Commands
 {
     public record UpdateCollection
-        (int CollectionId, string Name) : MediatR.IRequest<Either<BaseError, Unit>>;
+        (int CollectionId, string Name) : MediatR.IRequest<Either<BaseError, Unit>>
+    {
+        public Option<bool> UseCustomPlaybackOrder { get; set; } = None;
+    }
 }

ErsatzTV.Application/MediaCollections/Commands/UpdateCollectionCustomOrder.cs

@@ -0,0 +1,13 @@
+using System.Collections.Generic;
+using ErsatzTV.Core;
+using LanguageExt;
+
+namespace ErsatzTV.Application.MediaCollections.Commands
+{
+    public record UpdateCollectionCustomOrder
+    (
+        int CollectionId,
+        List<MediaItemCustomOrder> MediaItemCustomOrders) : MediatR.IRequest<Either<BaseError, Unit>>;
+
+    public record MediaItemCustomOrder(int MediaItemId, int CustomIndex);
+}

ErsatzTV.Application/MediaCollections/Commands/UpdateCollectionCustomOrderHandler.cs

@@ -0,0 +1,66 @@
+using System.Linq;
+using System.Threading;
+using System.Threading.Channels;
+using System.Threading.Tasks;
+using ErsatzTV.Application.Playouts.Commands;
+using ErsatzTV.Core;
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Interfaces.Repositories;
+using LanguageExt;
+
+namespace ErsatzTV.Application.MediaCollections.Commands
+{
+    public class
+        UpdateCollectionCustomOrderHandler : MediatR.IRequestHandler<UpdateCollectionCustomOrder,
+            Either<BaseError, Unit>>
+    {
+        private readonly ChannelWriter<IBackgroundServiceRequest> _channel;
+        private readonly IMediaCollectionRepository _mediaCollectionRepository;
+
+        public UpdateCollectionCustomOrderHandler(
+            IMediaCollectionRepository mediaCollectionRepository,
+            ChannelWriter<IBackgroundServiceRequest> channel)
+        {
+            _mediaCollectionRepository = mediaCollectionRepository;
+            _channel = channel;
+        }
+
+        public Task<Either<BaseError, Unit>> Handle(
+            UpdateCollectionCustomOrder request,
+            CancellationToken cancellationToken) =>
+            Validate(request)
+                .MapT(c => ApplyUpdateRequest(c, request))
+                .Bind(v => v.ToEitherAsync());
+
+        private async Task<Unit> ApplyUpdateRequest(Collection c, UpdateCollectionCustomOrder request)
+        {
+            foreach (MediaItemCustomOrder updateItem in request.MediaItemCustomOrders)
+            {
+                Option<CollectionItem> maybeCollectionItem =
+                    c.CollectionItems.FirstOrDefault(ci => ci.MediaItemId == updateItem.MediaItemId);
+
+                maybeCollectionItem.IfSome(ci => ci.CustomIndex = updateItem.CustomIndex);
+            }
+
+            if (await _mediaCollectionRepository.Update(c))
+            {
+                // rebuild all playouts that use this collection
+                foreach (int playoutId in await _mediaCollectionRepository.PlayoutIdsUsingCollection(
+                    request.CollectionId))
+                {
+                    await _channel.WriteAsync(new BuildPlayout(playoutId, true));
+                }
+            }
+
+            return Unit.Default;
+        }
+
+        private Task<Validation<BaseError, Collection>> Validate(UpdateCollectionCustomOrder request) =>
+            CollectionMustExist(request);
+
+        private Task<Validation<BaseError, Collection>> CollectionMustExist(
+            UpdateCollectionCustomOrder request) =>
+            _mediaCollectionRepository.Get(request.CollectionId)
+                .Map(v => v.ToValidation<BaseError>("Collection does not exist."));
+    }
+}

ErsatzTV.Application/MediaCollections/Commands/UpdateCollectionHandler.cs

@@ -1,5 +1,7 @@
 using System.Threading;
+using System.Threading.Channels;
 using System.Threading.Tasks;
+using ErsatzTV.Application.Playouts.Commands;
 using ErsatzTV.Core;
 using ErsatzTV.Core.Domain;
 using ErsatzTV.Core.Interfaces.Repositories;
@@ -9,10 +11,16 @@ namespace ErsatzTV.Application.MediaCollections.Commands
 {
     public class UpdateCollectionHandler : MediatR.IRequestHandler<UpdateCollection, Either<BaseError, Unit>>
     {
+        private readonly ChannelWriter<IBackgroundServiceRequest> _channel;
         private readonly IMediaCollectionRepository _mediaCollectionRepository;
 
-        public UpdateCollectionHandler(IMediaCollectionRepository mediaCollectionRepository) =>
+        public UpdateCollectionHandler(
+            IMediaCollectionRepository mediaCollectionRepository,
+            ChannelWriter<IBackgroundServiceRequest> channel)
+        {
             _mediaCollectionRepository = mediaCollectionRepository;
+            _channel = channel;
+        }
 
         public Task<Either<BaseError, Unit>> Handle(
             UpdateCollection request,
@@ -21,10 +29,21 @@ namespace ErsatzTV.Application.MediaCollections.Commands
                 .MapT(c => ApplyUpdateRequest(c, request))
                 .Bind(v => v.ToEitherAsync());
 
-        private async Task<Unit> ApplyUpdateRequest(Collection c, UpdateCollection update)
+        private async Task<Unit> ApplyUpdateRequest(Collection c, UpdateCollection request)
         {
-            c.Name = update.Name;
-            await _mediaCollectionRepository.Update(c);
+            c.Name = request.Name;
+            request.UseCustomPlaybackOrder.IfSome(
+                useCustomPlaybackOrder => c.UseCustomPlaybackOrder = useCustomPlaybackOrder);
+            if (await _mediaCollectionRepository.Update(c) && request.UseCustomPlaybackOrder.IsSome)
+            {
+                // rebuild all playouts that use this collection
+                foreach (int playoutId in await _mediaCollectionRepository.PlayoutIdsUsingCollection(
+                    request.CollectionId))
+                {
+                    await _channel.WriteAsync(new BuildPlayout(playoutId, true));
+                }
+            }
+
             return Unit.Default;
         }
 

ErsatzTV.Application/MediaCollections/MediaCollectionViewModel.cs

@@ -3,6 +3,7 @@
 namespace ErsatzTV.Application.MediaCollections
 {
     public record MediaCollectionViewModel(int Id, string Name) : MediaCardViewModel(
+        Id,
         Name,
         string.Empty,
         Name,

ErsatzTV.Core.Tests/Fakes/FakeMediaCollectionRepository.cs

@@ -14,17 +14,22 @@ namespace ErsatzTV.Core.Tests.Fakes
         private readonly Map<int, List<MediaItem>> _data;
 
         public FakeMediaCollectionRepository(Map<int, List<MediaItem>> data) => _data = data;
+
         public Task<Collection> Add(Collection collection) => throw new NotSupportedException();
         public Task<bool> AddMediaItem(int collectionId, int mediaItemId) => throw new NotSupportedException();
         public Task<bool> AddMediaItems(int collectionId, List<int> mediaItemIds) => throw new NotSupportedException();
-
         public Task<Option<Collection>> Get(int id) => throw new NotSupportedException();
         public Task<Option<Collection>> GetCollectionWithItems(int id) => throw new NotSupportedException();
         public Task<Option<Collection>> GetCollectionWithItemsUntracked(int id) => throw new NotSupportedException();
+
+        public Task<Option<Collection>> GetCollectionWithCollectionItemsUntracked(int id) =>
+            throw new NotSupportedException();
+
         public Task<List<Collection>> GetAll() => throw new NotSupportedException();
         public Task<Option<List<MediaItem>>> GetItems(int id) => Some(_data[id].ToList()).AsTask();
         Task<bool> IMediaCollectionRepository.Update(Collection collection) => throw new NotSupportedException();
         public Task Delete(int collectionId) => throw new NotSupportedException();
         public Task<List<int>> PlayoutIdsUsingCollection(int collectionId) => throw new NotSupportedException();
+        public Task<bool> IsCustomPlaybackOrder(int collectionId) => false.AsTask();
     }
 }

ErsatzTV.Core.Tests/Scheduling/CustomOrderContentTests.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Scheduling;
+using FluentAssertions;
+using NUnit.Framework;
+using static LanguageExt.Prelude;
+
+namespace ErsatzTV.Core.Tests.Scheduling
+{
+    public class CustomOrderContentTests
+    {
+        [Test]
+        public void MediaItems_Should_Sort_By_CustomOrder()
+        {
+            Collection collection = CreateCollection(10);
+            List<MediaItem> contents = Episodes(10);
+            var state = new CollectionEnumeratorState();
+
+            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);
+
+            for (var i = 10; i >= 1; i--)
+            {
+                customOrderContent.Current.IsSome.Should().BeTrue();
+                customOrderContent.Current.Map(x => x.Id).IfNone(-1).Should().Be(i);
+                customOrderContent.MoveNext();
+            }
+        }
+
+        [Test]
+        public void State_Index_Should_Increment()
+        {
+            Collection collection = CreateCollection(10);
+            List<MediaItem> contents = Episodes(10);
+            var state = new CollectionEnumeratorState();
+
+            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);
+
+            for (var i = 0; i < 10; i++)
+            {
+                customOrderContent.State.Index.Should().Be(i % 10);
+                customOrderContent.MoveNext();
+            }
+        }
+
+        [Test]
+        public void State_Should_Impact_Iterator_Start()
+        {
+            Collection collection = CreateCollection(10);
+            List<MediaItem> contents = Episodes(10);
+            var state = new CollectionEnumeratorState { Index = 5 };
+
+            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);
+
+            for (var i = 5; i >= 1; i--)
+            {
+                customOrderContent.Current.IsSome.Should().BeTrue();
+                customOrderContent.Current.Map(x => x.Id).IfNone(-1).Should().Be(i);
+                customOrderContent.State.Index.Should().Be(5 - i + 5); // 5 through 10
+                customOrderContent.MoveNext();
+            }
+        }
+
+        private static Collection CreateCollection(int episodeCount)
+        {
+            var collection = new Collection { CollectionItems = new List<CollectionItem>() };
+
+            for (var i = 1; i <= episodeCount; i++)
+            {
+                collection.CollectionItems.Add(
+                    new CollectionItem
+                    {
+                        MediaItemId = i,
+                        // reverse order
+                        CustomIndex = episodeCount - i
+                    });
+            }
+
+            return collection;
+        }
+
+
+        private static List<MediaItem> Episodes(int count) =>
+            Range(1, count).Map(
+                    i => (MediaItem) new Episode
+                    {
+                        Id = i,
+                        EpisodeMetadata = new List<EpisodeMetadata>
+                        {
+                            new()
+                            {
+                                ReleaseDate = new DateTime(2020, 1, i)
+                            }
+                        }
+                    })
+                .Reverse()
+                .ToList();
+    }
+}

ErsatzTV.Core/Domain/Collection/Collection.cs

@@ -6,6 +6,7 @@ namespace ErsatzTV.Core.Domain
     {
         public int Id { get; set; }
         public string Name { get; set; }
+        public bool UseCustomPlaybackOrder { get; set; }
         public List<MediaItem> MediaItems { get; set; }
         public List<CollectionItem> CollectionItems { get; set; }
     }

ErsatzTV.Core/Domain/Collection/CollectionItem.cs

@@ -6,5 +6,6 @@
         public Collection Collection { get; set; }
         public int MediaItemId { get; set; }
         public MediaItem MediaItem { get; set; }
+        public int? CustomIndex { get; set; }
     }
 }

ErsatzTV.Core/Interfaces/Repositories/IMediaCollectionRepository.cs

@@ -13,10 +13,12 @@ namespace ErsatzTV.Core.Interfaces.Repositories
         Task<Option<Collection>> Get(int id);
         Task<Option<Collection>> GetCollectionWithItems(int id);
         Task<Option<Collection>> GetCollectionWithItemsUntracked(int id);
+        Task<Option<Collection>> GetCollectionWithCollectionItemsUntracked(int id);
         Task<List<Collection>> GetAll();
         Task<Option<List<MediaItem>>> GetItems(int id);
         Task<bool> Update(Collection collection);
         Task Delete(int collectionId);
         Task<List<int>> PlayoutIdsUsingCollection(int collectionId);
+        Task<bool> IsCustomPlaybackOrder(int collectionId);
     }
 }

ErsatzTV.Core/Scheduling/CustomOrderCollectionEnumerator.cs

@@ -0,0 +1,38 @@
+using System.Collections.Generic;
+using System.Linq;
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Interfaces.Scheduling;
+using LanguageExt;
+using static LanguageExt.Prelude;
+
+namespace ErsatzTV.Core.Scheduling
+{
+    public class CustomOrderCollectionEnumerator : IMediaCollectionEnumerator
+    {
+        private readonly IList<MediaItem> _sortedMediaItems;
+
+        public CustomOrderCollectionEnumerator(
+            Collection collection,
+            List<MediaItem> mediaItems,
+            CollectionEnumeratorState state)
+        {
+            // TODO: this will break if we allow shows and seasons
+            _sortedMediaItems = collection.CollectionItems
+                .OrderBy(ci => ci.CustomIndex)
+                .Map(ci => mediaItems.First(mi => mi.Id == ci.MediaItemId))
+                .ToList();
+
+            State = new CollectionEnumeratorState { Seed = state.Seed };
+            while (State.Index < state.Index)
+            {
+                MoveNext();
+            }
+        }
+
+        public CollectionEnumeratorState State { get; }
+
+        public Option<MediaItem> Current => _sortedMediaItems.Any() ? _sortedMediaItems[State.Index] : None;
+
+        public void MoveNext() => State.Index = (State.Index + 1) % _sortedMediaItems.Count;
+    }
+}

ErsatzTV.Core/Scheduling/PlayoutBuilder.cs

@@ -78,7 +78,8 @@ namespace ErsatzTV.Core.Scheduling
                 playout.Channel.Number,
                 playout.Channel.Name);
 
-            Option<CollectionKey> emptyCollection = collectionMediaItems.Find(c => !c.Value.Any()).Map(c => c.Key);
+            Option<CollectionKey> emptyCollection =
+                collectionMediaItems.Find(c => !c.Value.Any()).Map(c => c.Key);
             if (emptyCollection.IsSome)
             {
                 _logger.LogError(
@@ -117,9 +118,15 @@ namespace ErsatzTV.Core.Scheduling
                 playout.ProgramScheduleAnchors.Clear();
             }
 
-            var sortedScheduleItems = playout.ProgramSchedule.Items.OrderBy(i => i.Index).ToList();
-            Map<CollectionKey, IMediaCollectionEnumerator> collectionEnumerators =
-                MapExtensions.Map(collectionMediaItems, (c, i) => GetMediaCollectionEnumerator(playout, c, i));
+            var sortedScheduleItems =
+                playout.ProgramSchedule.Items.OrderBy(i => i.Index).ToList();
+            var collectionEnumerators = new Dictionary<CollectionKey, IMediaCollectionEnumerator>();
+            foreach ((CollectionKey collectionKey, List<MediaItem> mediaItems) in collectionMediaItems)
+            {
+                IMediaCollectionEnumerator enumerator =
+                    await GetMediaCollectionEnumerator(playout, collectionKey, mediaItems);
+                collectionEnumerators.Add(collectionKey, enumerator);
+            }
 
             // find start anchor
             PlayoutAnchor startAnchor = FindStartAnchor(playout, playoutStart, sortedScheduleItems);
@@ -357,20 +364,20 @@ namespace ErsatzTV.Core.Scheduling
 
         private static List<PlayoutProgramScheduleAnchor> BuildProgramScheduleAnchors(
             Playout playout,
-            Map<CollectionKey, IMediaCollectionEnumerator> collectionEnumerators)
+            Dictionary<CollectionKey, IMediaCollectionEnumerator> collectionEnumerators)
         {
             var result = new List<PlayoutProgramScheduleAnchor>();
 
             foreach (CollectionKey collectionKey in collectionEnumerators.Keys)
             {
-                Option<PlayoutProgramScheduleAnchor> maybeExisting = playout.ProgramScheduleAnchors
-                    .FirstOrDefault(
-                        a => a.CollectionType == collectionKey.CollectionType
-                             && a.CollectionId == collectionKey.CollectionId
-                             && a.MediaItemId == collectionKey.MediaItemId);
+                Option<PlayoutProgramScheduleAnchor> maybeExisting = playout.ProgramScheduleAnchors.FirstOrDefault(
+                    a => a.CollectionType == collectionKey.CollectionType
+                         && a.CollectionId == collectionKey.CollectionId
+                         && a.MediaItemId == collectionKey.MediaItemId);
 
-                var maybeEnumeratorState = collectionEnumerators.GroupBy(e => e.Key, e => e.Value.State)
-                    .ToDictionary(mcs => mcs.Key, mcs => mcs.Head());
+                var maybeEnumeratorState = collectionEnumerators.GroupBy(e => e.Key, e => e.Value.State).ToDictionary(
+                    mcs => mcs.Key,
+                    mcs => mcs.Head());
 
                 PlayoutProgramScheduleAnchor scheduleAnchor = maybeExisting.Match(
                     existing =>
@@ -396,22 +403,37 @@ namespace ErsatzTV.Core.Scheduling
             return result;
         }
 
-        private static IMediaCollectionEnumerator GetMediaCollectionEnumerator(
+        private async Task<IMediaCollectionEnumerator> GetMediaCollectionEnumerator(
             Playout playout,
             CollectionKey collectionKey,
             List<MediaItem> mediaItems)
         {
-            Option<PlayoutProgramScheduleAnchor> maybeAnchor = playout.ProgramScheduleAnchors
-                .FirstOrDefault(
-                    a => a.ProgramScheduleId == playout.ProgramScheduleId
-                         && a.CollectionType == collectionKey.CollectionType
-                         && a.CollectionId == collectionKey.CollectionId
-                         && a.MediaItemId == collectionKey.MediaItemId);
+            Option<PlayoutProgramScheduleAnchor> maybeAnchor = playout.ProgramScheduleAnchors.FirstOrDefault(
+                a => a.ProgramScheduleId == playout.ProgramScheduleId
+                     && a.CollectionType == collectionKey.CollectionType
+                     && a.CollectionId == collectionKey.CollectionId
+                     && a.MediaItemId == collectionKey.MediaItemId);
 
             CollectionEnumeratorState state = maybeAnchor.Match(
                 anchor => anchor.EnumeratorState,
                 () => new CollectionEnumeratorState { Seed = Random.Next(), Index = 0 });
 
+            if (await _mediaCollectionRepository.IsCustomPlaybackOrder(collectionKey.CollectionId ?? 0))
+            {
+                Option<Collection> collectionWithItems =
+                    await _mediaCollectionRepository.GetCollectionWithCollectionItemsUntracked(
+                        collectionKey.CollectionId ?? 0);
+
+                if (collectionKey.CollectionType == ProgramScheduleItemCollectionType.Collection &&
+                    collectionWithItems.IsSome)
+                {
+                    return new CustomOrderCollectionEnumerator(
+                        collectionWithItems.ValueUnsafe(),
+                        mediaItems,
+                        state);
+                }
+            }
+
             switch (playout.ProgramSchedule.MediaCollectionPlaybackOrder)
             {
                 case PlaybackOrder.Chronological:

ErsatzTV.Infrastructure/Data/Configurations/Collection/CollectionItemConfiguration.cs

@@ -0,0 +1,11 @@
+using ErsatzTV.Core.Domain;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ErsatzTV.Infrastructure.Data.Configurations
+{
+    public class CollectionItemConfiguration : IEntityTypeConfiguration<CollectionItem>
+    {
+        public void Configure(EntityTypeBuilder<CollectionItem> builder) => builder.ToTable("CollectionItem");
+    }
+}

ErsatzTV.Infrastructure/Data/Repositories/MediaCollectionRepository.cs

@@ -92,6 +92,7 @@ namespace ErsatzTV.Infrastructure.Data.Repositories
 
         public Task<Option<Collection>> Get(int id) =>
             _dbContext.Collections
+                .Include(c => c.CollectionItems)
                 .OrderBy(c => c.Id)
                 .SingleOrDefaultAsync(c => c.Id == id)
                 .Map(Optional);
@@ -120,6 +121,7 @@ namespace ErsatzTV.Infrastructure.Data.Repositories
         public Task<Option<Collection>> GetCollectionWithItemsUntracked(int id) =>
             _dbContext.Collections
                 .AsNoTracking()
+                .Include(c => c.CollectionItems)
                 .Include(c => c.MediaItems)
                 .ThenInclude(i => i.LibraryPath)
                 .Include(c => c.MediaItems)
@@ -145,6 +147,13 @@ namespace ErsatzTV.Infrastructure.Data.Repositories
                 .SingleOrDefaultAsync(c => c.Id == id)
                 .Map(Optional);
 
+        public Task<Option<Collection>> GetCollectionWithCollectionItemsUntracked(int id) =>
+            _dbContext.Collections
+                .Include(c => c.CollectionItems)
+                .OrderBy(c => c.Id)
+                .SingleOrDefaultAsync(c => c.Id == id)
+                .Map(Optional);
+
         public Task<List<Collection>> GetAll() =>
             _dbContext.Collections.ToListAsync();
 
@@ -174,6 +183,11 @@ namespace ErsatzTV.Infrastructure.Data.Repositories
                     new { CollectionId = collectionId })
                 .Map(result => result.ToList());
 
+        public Task<bool> IsCustomPlaybackOrder(int collectionId) =>
+            _dbConnection.QuerySingleAsync<bool>(
+                @"SELECT UseCustomPlaybackOrder FROM Collection WHERE Id = @CollectionId",
+                new { CollectionId = collectionId });
+
         private async Task<List<MediaItem>> GetItemsForCollection(Collection collection)
         {
             var result = new List<MediaItem>();

ErsatzTV.Infrastructure/Data/TvContext.cs

@@ -34,6 +34,7 @@ namespace ErsatzTV.Infrastructure.Data
         public DbSet<EpisodeMetadata> EpisodeMetadata { get; set; }
         public DbSet<PlexMovie> PlexMovies { get; set; }
         public DbSet<Collection> Collections { get; set; }
+        public DbSet<CollectionItem> CollectionItems { get; set; }
         public DbSet<ProgramSchedule> ProgramSchedules { get; set; }
         public DbSet<Playout> Playouts { get; set; }
         public DbSet<PlayoutItem> PlayoutItems { get; set; }

ErsatzTV.Infrastructure/Migrations/20210312113202_Add_CollectionItem_CustomIndex.cs

@@ -0,0 +1,19 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace ErsatzTV.Infrastructure.Migrations
+{
+    public partial class Add_CollectionItem_CustomIndex : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder) =>
+            migrationBuilder.AddColumn<int>(
+                "CustomIndex",
+                "CollectionItem",
+                "INTEGER",
+                nullable: true);
+
+        protected override void Down(MigrationBuilder migrationBuilder) =>
+            migrationBuilder.DropColumn(
+                "CustomIndex",
+                "CollectionItem");
+    }
+}

ErsatzTV.Infrastructure/Migrations/20210312183644_Add_Collection_UseCustomPlaybackOrder.cs

@@ -0,0 +1,20 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace ErsatzTV.Infrastructure.Migrations
+{
+    public partial class Add_Collection_UseCustomPlaybackOrder : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder) =>
+            migrationBuilder.AddColumn<bool>(
+                "UseCustomPlaybackOrder",
+                "Collection",
+                "INTEGER",
+                nullable: false,
+                defaultValue: false);
+
+        protected override void Down(MigrationBuilder migrationBuilder) =>
+            migrationBuilder.DropColumn(
+                "UseCustomPlaybackOrder",
+                "Collection");
+    }
+}

ErsatzTV.Infrastructure/Migrations/TvContextModelSnapshot.cs

@@ -110,6 +110,9 @@ namespace ErsatzTV.Infrastructure.Migrations
                     b.Property<string>("Name")
                         .HasColumnType("TEXT");
 
+                    b.Property<bool>("UseCustomPlaybackOrder")
+                        .HasColumnType("INTEGER");
+
                     b.HasKey("Id");
 
                     b.ToTable("Collection");
@@ -125,6 +128,9 @@ namespace ErsatzTV.Infrastructure.Migrations
                     b.Property<int>("MediaItemId")
                         .HasColumnType("INTEGER");
 
+                    b.Property<int?>("CustomIndex")
+                        .HasColumnType("INTEGER");
+
                     b.HasKey("CollectionId", "MediaItemId");
 
                     b.HasIndex("MediaItemId");

ErsatzTV/Controllers/SortController.cs

@@ -0,0 +1,35 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using ErsatzTV.Application.MediaCollections.Commands;
+using MediatR;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ErsatzTV.Controllers
+{
+    [ApiController]
+    [ApiExplorerSettings(IgnoreApi = true)]
+    public class SortController : ControllerBase
+    {
+        private readonly IMediator _mediator;
+
+        public SortController(IMediator mediator) => _mediator = mediator;
+
+        [HttpPost("media/collections/{collectionId}/items")]
+        public Task SortCollectionItems(
+            int collectionId,
+            [FromForm]
+            SortedMediaItemIds sortedMediaItemIds)
+        {
+            var ids = sortedMediaItemIds.Item.Map(int.Parse).ToList();
+
+            var request = new UpdateCollectionCustomOrder(
+                collectionId,
+                ids.Map(i => new MediaItemCustomOrder(i, ids.IndexOf(i))).ToList());
+
+            return _mediator.Send(request);
+        }
+    }
+
+    public record SortedMediaItemIds(List<string> Item);
+}

ErsatzTV/Pages/CollectionItems.razor

@@ -5,6 +5,7 @@
 @inherits MultiSelectBase<CollectionItems>
 @inject NavigationManager NavigationManager
 @inject ChannelWriter<IBackgroundServiceRequest> Channel
+@inject IJSRuntime JsRuntime
 
 <MudPaper Square="true" Style="display: flex; height: 64px; left: 240px; padding: 0; position: fixed; right: 0; z-index: 100;">
     <div style="align-items: center; display: flex; flex-direction: row; margin-bottom: auto; margin-top: auto; width: 100%;" class="ml-6 mr-6">
@@ -51,6 +52,16 @@
             {
                 <MudLink Class="ml-4" Href="@(NavigationManager.Uri.Split("#").Head() + "#episodes")">@_data.EpisodeCards.Count Episodes</MudLink>
             }
+            @if (SupportsCustomOrdering())
+            {
+                <div style="margin-left: auto">
+                    <MudSwitch T="bool"
+                               Checked="@_data.UseCustomPlaybackOrder"
+                               Color="Color.Primary"
+                               CheckedChanged="@OnUseCustomOrderChanged"
+                               Label="Use Custom Playback Order"/>
+                </div>
+            }
         }
     </div>
 </MudPaper>
@@ -65,8 +76,8 @@
             Movies
         </MudText>
 
-        <MudContainer MaxWidth="MaxWidth.False" Class="media-card-grid">
-            @foreach (MovieCardViewModel card in _data.MovieCards.OrderBy(m => m.SortTitle))
+        <MudContainer MaxWidth="MaxWidth.False" Class="media-card-grid" UserAttributes="@(new Dictionary<string, object> { { "id", "sortable-collection" } })">
+            @foreach (MovieCardViewModel card in OrderMovies(_data.MovieCards))
             {
                 <MediaCard Data="@card"
                            Link="@($"/media/movies/{card.MovieId}")"
@@ -163,6 +174,9 @@
 
     private CollectionCardResultsViewModel _data;
 
+    private bool SupportsCustomOrdering() =>
+        _data.MovieCards.Any() && !_data.ShowCards.Any() && !_data.SeasonCards.Any() && !_data.EpisodeCards.Any();
+
     protected override async Task OnParametersSetAsync() => await RefreshData();
 
     protected override async Task RefreshData()
@@ -175,6 +189,30 @@
             error => NavigationManager.NavigateTo("404"));
     }
 
+    private IOrderedEnumerable<MovieCardViewModel> OrderMovies(List<MovieCardViewModel> movies)
+    {
+        if (_data.UseCustomPlaybackOrder)
+        {
+            return movies.OrderBy(m => m.CustomIndex);
+        }
+
+        return movies.OrderBy(m => m.SortTitle);
+    }
+
+    protected override async Task OnAfterRenderAsync(bool firstRender)
+    {
+        await JsRuntime.InvokeVoidAsync("sortableCollection", Id);
+        if (_data.UseCustomPlaybackOrder)
+        {
+            await JsRuntime.InvokeVoidAsync("enableSorting");
+        }
+        else
+        {
+            await JsRuntime.InvokeVoidAsync("disableSorting");
+        }
+        await base.OnAfterRenderAsync(firstRender);
+    }
+
     private void SelectClicked(MediaCardViewModel card, MouseEventArgs e)
     {
         List<MediaCardViewModel> GetSortedItems()
@@ -255,4 +293,11 @@
         }
     }
 
+    private async Task OnUseCustomOrderChanged()
+    {
+        _data.UseCustomPlaybackOrder = !_data.UseCustomPlaybackOrder;
+        var request = new UpdateCollection(Id, _data.Name) { UseCustomPlaybackOrder = _data.UseCustomPlaybackOrder };
+        await Mediator.Send(request);
+    }
+
 }

ErsatzTV/Pages/_Host.cshtml

@@ -17,7 +17,33 @@
     <link href="_content/MudBlazor/MudBlazor.min.css" rel="stylesheet"/>
     <link href="css/site.css" rel="stylesheet"/>
     <link href="ErsatzTV.styles.css" rel="stylesheet"/>
+    <link href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css" rel="stylesheet">
+    <script src="https://code.jquery.com/jquery-1.12.4.js"></script>
+    <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
     @await Html.PartialAsync("../Shared/_Favicons")
+    <script>
+        function sortableCollection(collectionId) {
+            $("#sortable-collection").sortable({
+                update: function(event, ui) {
+                    const data = $(this).sortable('serialize');
+                    $.ajax({
+                        data: data,
+                        type: 'POST',
+                        url: `/media/collections/${collectionId}/items`
+                    });
+                }
+            });
+            $("#sortable-collection").disableSelection();
+        }
+
+        function disableSorting() {
+            $("#sortable-collection").sortable("option", "disabled", true);
+        }
+
+        function enableSorting() {
+            $("#sortable-collection").sortable("option", "disabled", false);
+        }
+    </script>
 </head>
 <body>
 <component type="typeof(App)" render-mode="ServerPrerendered"/>

ErsatzTV/Shared/MediaCard.razor

@@ -2,7 +2,7 @@
 @using Unit = LanguageExt.Unit
 @inject IMediator Mediator
 
-<div class="@((ContainerClass ?? "media-card-container mr-6") + " pb-3")">
+<div class="@((ContainerClass ?? "media-card-container mr-6") + " pb-3")" id="@($"item_{Data.MediaItemId}")">
     @if (!string.IsNullOrWhiteSpace(Link))
     {
         <div class="@(IsSelected ? DeleteClicked.HasDelegate ? "media-card-selected-delete" : "media-card-selected" : "")"