Merge pull request #9446 from 1337joe/audiobook-grouping-fixes

16 files changed, 153 insertions, 57 deletions

diff --git a/Emby.Server.Implementations/Library/LibraryManager.cs b/Emby.Server.Implementations/Library/LibraryManager.cs
index 66bd68ddd..e5c520ca2 100644
--- a/Emby.Server.Implementations/Library/LibraryManager.cs
+++ b/Emby.Server.Implementations/Library/LibraryManager.cs
@@ -113,6 +113,7 @@ namespace Emby.Server.Implementations.Library
         /// <param name="imageProcessor">The image processor.</param>
         /// <param name="memoryCache">The memory cache.</param>
         /// <param name="namingOptions">The naming options.</param>
+        /// <param name="directoryService">The directory service.</param>
         public LibraryManager(
             IServerApplicationHost appHost,
             ILoggerFactory loggerFactory,
@@ -128,7 +129,8 @@ namespace Emby.Server.Implementations.Library
             IItemRepository itemRepository,
             IImageProcessor imageProcessor,
             IMemoryCache memoryCache,
-            NamingOptions namingOptions)
+            NamingOptions namingOptions,
+            IDirectoryService directoryService)
         {
             _appHost = appHost;
             _logger = loggerFactory.CreateLogger<LibraryManager>();
@@ -146,7 +148,7 @@ namespace Emby.Server.Implementations.Library
             _memoryCache = memoryCache;
             _namingOptions = namingOptions;
 
-            _extraResolver = new ExtraResolver(loggerFactory.CreateLogger<ExtraResolver>(), namingOptions);
+            _extraResolver = new ExtraResolver(loggerFactory.CreateLogger<ExtraResolver>(), namingOptions, directoryService);
 
             _configurationManager.ConfigurationUpdated += ConfigurationUpdated;
 
@@ -537,7 +539,7 @@ namespace Emby.Server.Implementations.Library
                 collectionType = GetContentTypeOverride(fullPath, true);
             }
 
-            var args = new ItemResolveArgs(_configurationManager.ApplicationPaths, directoryService)
+            var args = new ItemResolveArgs(_configurationManager.ApplicationPaths, this)
             {
                 Parent = parent,
                 FileInfo = fileInfo,
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
index 69e905798..a74f82475 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
@@ -192,7 +192,8 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
                     continue;
                 }
 
-                if (resolvedItem.Files.Count == 0)
+                // Until multi-part books are handled letting files stack hides them from browsing in the client
+                if (resolvedItem.Files.Count == 0 || resolvedItem.Extras.Count > 0 || resolvedItem.AlternateVersions.Count > 0)
                 {
                     continue;
                 }
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
index a922e3685..bbc70701c 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
@@ -25,16 +25,19 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
     {
         private readonly ILogger<MusicAlbumResolver> _logger;
         private readonly NamingOptions _namingOptions;
+        private readonly IDirectoryService _directoryService;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="MusicAlbumResolver"/> class.
         /// </summary>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">The naming options.</param>
-        public MusicAlbumResolver(ILogger<MusicAlbumResolver> logger, NamingOptions namingOptions)
+        /// <param name="directoryService">The directory service.</param>
+        public MusicAlbumResolver(ILogger<MusicAlbumResolver> logger, NamingOptions namingOptions, IDirectoryService directoryService)
         {
             _logger = logger;
             _namingOptions = namingOptions;
+            _directoryService = directoryService;
         }
 
         /// <summary>
@@ -109,7 +112,7 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
                 }
 
                 // If args contains music it's a music album
-                if (ContainsMusic(args.FileSystemChildren, true, args.DirectoryService))
+                if (ContainsMusic(args.FileSystemChildren, true, _directoryService))
                 {
                     return true;
                 }
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
index 2538c2b5b..c858dc53d 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
@@ -6,6 +6,7 @@ using System.Threading.Tasks;
 using Emby.Naming.Common;
 using MediaBrowser.Controller.Entities.Audio;
 using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Providers;
 using MediaBrowser.Controller.Resolvers;
 using MediaBrowser.Model.Entities;
 using Microsoft.Extensions.Logging;
@@ -18,19 +19,23 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
     public class MusicArtistResolver : ItemResolver<MusicArtist>
     {
         private readonly ILogger<MusicAlbumResolver> _logger;
-        private NamingOptions _namingOptions;
+        private readonly NamingOptions _namingOptions;
+        private readonly IDirectoryService _directoryService;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="MusicArtistResolver"/> class.
         /// </summary>
         /// <param name="logger">Instance of the <see cref="MusicAlbumResolver"/> interface.</param>
         /// <param name="namingOptions">The <see cref="NamingOptions"/>.</param>
+        /// <param name="directoryService">The directory service.</param>
         public MusicArtistResolver(
             ILogger<MusicAlbumResolver> logger,
-            NamingOptions namingOptions)
+            NamingOptions namingOptions,
+            IDirectoryService directoryService)
         {
             _logger = logger;
             _namingOptions = namingOptions;
+            _directoryService = directoryService;
         }
 
         /// <summary>
@@ -78,9 +83,7 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
                 return null;
             }
 
-            var directoryService = args.DirectoryService;
-
-            var albumResolver = new MusicAlbumResolver(_logger, _namingOptions);
+            var albumResolver = new MusicAlbumResolver(_logger, _namingOptions, _directoryService);
 
             var directories = args.FileSystemChildren.Where(i => i.IsDirectory);
 
@@ -97,7 +100,7 @@ namespace Emby.Server.Implementations.Library.Resolvers.Audio
                 }
 
                 // If we contain a music album assume we are an artist folder
-                if (albumResolver.IsMusicAlbum(fileSystemInfo.FullName, directoryService))
+                if (albumResolver.IsMusicAlbum(fileSystemInfo.FullName, _directoryService))
                 {
                     // Stop once we see a music album
                     state.Stop();
diff --git a/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
index e8615e7db..9b133bef4 100644
--- a/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
@@ -25,14 +25,17 @@ namespace Emby.Server.Implementations.Library.Resolvers
     {
         private readonly ILogger _logger;
 
-        protected BaseVideoResolver(ILogger logger, NamingOptions namingOptions)
+        protected BaseVideoResolver(ILogger logger, NamingOptions namingOptions, IDirectoryService directoryService)
         {
             _logger = logger;
             NamingOptions = namingOptions;
+            DirectoryService = directoryService;
         }
 
         protected NamingOptions NamingOptions { get; }
 
+        protected IDirectoryService DirectoryService { get; }
+
         /// <summary>
         /// Resolves the specified args.
         /// </summary>
@@ -65,7 +68,7 @@ namespace Emby.Server.Implementations.Library.Resolvers
                     var filename = child.Name;
                     if (child.IsDirectory)
                     {
-                        if (IsDvdDirectory(child.FullName, filename, args.DirectoryService))
+                        if (IsDvdDirectory(child.FullName, filename, DirectoryService))
                         {
                             videoType = VideoType.Dvd;
                         }
diff --git a/Emby.Server.Implementations/Library/Resolvers/ExtraResolver.cs b/Emby.Server.Implementations/Library/Resolvers/ExtraResolver.cs
index 30c52e19d..0b255f673 100644
--- a/Emby.Server.Implementations/Library/Resolvers/ExtraResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/ExtraResolver.cs
@@ -4,6 +4,7 @@ using System.IO;
 using Emby.Naming.Common;
 using Emby.Naming.Video;
 using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Providers;
 using MediaBrowser.Controller.Resolvers;
 using MediaBrowser.Model.Entities;
 using Microsoft.Extensions.Logging;
@@ -25,11 +26,12 @@ namespace Emby.Server.Implementations.Library.Resolvers
         /// </summary>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">An instance of <see cref="NamingOptions"/>.</param>
-        public ExtraResolver(ILogger<ExtraResolver> logger, NamingOptions namingOptions)
+        /// <param name="directoryService">The directory service.</param>
+        public ExtraResolver(ILogger<ExtraResolver> logger, NamingOptions namingOptions, IDirectoryService directoryService)
         {
             _namingOptions = namingOptions;
-            _trailerResolvers = new IItemResolver[] { new GenericVideoResolver<Trailer>(logger, namingOptions) };
-            _videoResolvers = new IItemResolver[] { new GenericVideoResolver<Video>(logger, namingOptions) };
+            _trailerResolvers = new IItemResolver[] { new GenericVideoResolver<Trailer>(logger, namingOptions, directoryService) };
+            _videoResolvers = new IItemResolver[] { new GenericVideoResolver<Video>(logger, namingOptions, directoryService) };
         }
 
         /// <summary>
diff --git a/Emby.Server.Implementations/Library/Resolvers/GenericVideoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/GenericVideoResolver.cs
index 5e33b402d..ba320266a 100644
--- a/Emby.Server.Implementations/Library/Resolvers/GenericVideoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/GenericVideoResolver.cs
@@ -2,6 +2,7 @@
 
 using Emby.Naming.Common;
 using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Providers;
 using Microsoft.Extensions.Logging;
 
 namespace Emby.Server.Implementations.Library.Resolvers
@@ -18,8 +19,9 @@ namespace Emby.Server.Implementations.Library.Resolvers
         /// </summary>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">The naming options.</param>
-        public GenericVideoResolver(ILogger logger, NamingOptions namingOptions)
-            : base(logger, namingOptions)
+        /// <param name="directoryService">The directory service.</param>
+        public GenericVideoResolver(ILogger logger, NamingOptions namingOptions, IDirectoryService directoryService)
+            : base(logger, namingOptions, directoryService)
         {
         }
     }
diff --git a/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
index ef4fa1fd2..ea980b992 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
@@ -43,8 +43,9 @@ namespace Emby.Server.Implementations.Library.Resolvers.Movies
         /// <param name="imageProcessor">The image processor.</param>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">The naming options.</param>
-        public MovieResolver(IImageProcessor imageProcessor, ILogger<MovieResolver> logger, NamingOptions namingOptions)
-            : base(logger, namingOptions)
+        /// <param name="directoryService">The directory service.</param>
+        public MovieResolver(IImageProcessor imageProcessor, ILogger<MovieResolver> logger, NamingOptions namingOptions, IDirectoryService directoryService)
+            : base(logger, namingOptions, directoryService)
         {
             _imageProcessor = imageProcessor;
         }
@@ -97,12 +98,12 @@ namespace Emby.Server.Implementations.Library.Resolvers.Movies
 
                 if (string.Equals(collectionType, CollectionType.MusicVideos, StringComparison.OrdinalIgnoreCase))
                 {
-                    movie = FindMovie<MusicVideo>(args, args.Path, args.Parent, files, args.DirectoryService, collectionType, false);
+                    movie = FindMovie<MusicVideo>(args, args.Path, args.Parent, files, DirectoryService, collectionType, false);
                 }
 
                 if (string.Equals(collectionType, CollectionType.HomeVideos, StringComparison.OrdinalIgnoreCase))
                 {
-                    movie = FindMovie<Video>(args, args.Path, args.Parent, files, args.DirectoryService, collectionType, false);
+                    movie = FindMovie<Video>(args, args.Path, args.Parent, files, DirectoryService, collectionType, false);
                 }
 
                 if (string.IsNullOrEmpty(collectionType))
@@ -118,12 +119,12 @@ namespace Emby.Server.Implementations.Library.Resolvers.Movies
                         return null;
                     }
 
-                    movie = FindMovie<Movie>(args, args.Path, args.Parent, files, args.DirectoryService, collectionType, true);
+                    movie = FindMovie<Movie>(args, args.Path, args.Parent, files, DirectoryService, collectionType, true);
                 }
 
                 if (string.Equals(collectionType, CollectionType.Movies, StringComparison.OrdinalIgnoreCase))
                 {
-                    movie = FindMovie<Movie>(args, args.Path, args.Parent, files, args.DirectoryService, collectionType, true);
+                    movie = FindMovie<Movie>(args, args.Path, args.Parent, files, DirectoryService, collectionType, true);
                 }
 
                 // ignore extras
diff --git a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
index e11fb262e..9026160ff 100644
--- a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
@@ -1,7 +1,5 @@
 #nullable disable
 
-#pragma warning disable CS1591
-
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -12,15 +10,20 @@ using Jellyfin.Extensions;
 using MediaBrowser.Controller.Drawing;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Providers;
 using MediaBrowser.Controller.Resolvers;
 using MediaBrowser.Model.Entities;
 
 namespace Emby.Server.Implementations.Library.Resolvers
 {
+    /// <summary>
+    /// Class PhotoResolver.
+    /// </summary>
     public class PhotoResolver : ItemResolver<Photo>
     {
         private readonly IImageProcessor _imageProcessor;
         private readonly NamingOptions _namingOptions;
+        private readonly IDirectoryService _directoryService;
 
         private static readonly HashSet<string> _ignoreFiles = new HashSet<string>(StringComparer.OrdinalIgnoreCase)
         {
@@ -35,10 +38,17 @@ namespace Emby.Server.Implementations.Library.Resolvers
             "default"
         };
 
-        public PhotoResolver(IImageProcessor imageProcessor, NamingOptions namingOptions)
+        /// <summary>
+        /// Initializes a new instance of the <see cref="PhotoResolver"/> class.
+        /// </summary>
+        /// <param name="imageProcessor">The image processor.</param>
+        /// <param name="namingOptions">The naming options.</param>
+        /// <param name="directoryService">The directory service.</param>
+        public PhotoResolver(IImageProcessor imageProcessor, NamingOptions namingOptions, IDirectoryService directoryService)
         {
             _imageProcessor = imageProcessor;
             _namingOptions = namingOptions;
+            _directoryService = directoryService;
         }
 
         /// <summary>
@@ -61,7 +71,7 @@ namespace Emby.Server.Implementations.Library.Resolvers
                         var filename = Path.GetFileNameWithoutExtension(args.Path);
 
                         // Make sure the image doesn't belong to a video file
-                        var files = args.DirectoryService.GetFiles(Path.GetDirectoryName(args.Path));
+                        var files = _directoryService.GetFiles(Path.GetDirectoryName(args.Path));
 
                         foreach (var file in files)
                         {
diff --git a/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs b/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
index 0fcc5070b..392ee4c77 100644
--- a/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
@@ -5,6 +5,7 @@ using System.Linq;
 using Emby.Naming.Common;
 using MediaBrowser.Controller.Entities.TV;
 using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Providers;
 using MediaBrowser.Model.Entities;
 using Microsoft.Extensions.Logging;
 
@@ -20,8 +21,9 @@ namespace Emby.Server.Implementations.Library.Resolvers.TV
         /// </summary>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">The naming options.</param>
-        public EpisodeResolver(ILogger<EpisodeResolver> logger, NamingOptions namingOptions)
-            : base(logger, namingOptions)
+        /// <param name="directoryService">The directory service.</param>
+        public EpisodeResolver(ILogger<EpisodeResolver> logger, NamingOptions namingOptions, IDirectoryService directoryService)
+            : base(logger, namingOptions, directoryService)
         {
         }
 
diff --git a/MediaBrowser.Controller/Entities/AggregateFolder.cs b/MediaBrowser.Controller/Entities/AggregateFolder.cs
index 08c622cde..d789033f1 100644
--- a/MediaBrowser.Controller/Entities/AggregateFolder.cs
+++ b/MediaBrowser.Controller/Entities/AggregateFolder.cs
@@ -120,7 +120,7 @@ namespace MediaBrowser.Controller.Entities
 
             var path = ContainingFolderPath;
 
-            var args = new ItemResolveArgs(ConfigurationManager.ApplicationPaths, directoryService)
+            var args = new ItemResolveArgs(ConfigurationManager.ApplicationPaths, LibraryManager)
             {
                 FileInfo = FileSystem.GetDirectoryInfo(path)
             };
diff --git a/MediaBrowser.Controller/Entities/CollectionFolder.cs b/MediaBrowser.Controller/Entities/CollectionFolder.cs
index 5ac619d8f..095b261c0 100644
--- a/MediaBrowser.Controller/Entities/CollectionFolder.cs
+++ b/MediaBrowser.Controller/Entities/CollectionFolder.cs
@@ -288,7 +288,7 @@ namespace MediaBrowser.Controller.Entities
         {
             var path = ContainingFolderPath;
 
-            var args = new ItemResolveArgs(ConfigurationManager.ApplicationPaths, directoryService)
+            var args = new ItemResolveArgs(ConfigurationManager.ApplicationPaths, LibraryManager)
             {
                 FileInfo = FileSystem.GetDirectoryInfo(path),
                 Parent = GetParent() as Folder,
diff --git a/MediaBrowser.Controller/Library/ItemResolveArgs.cs b/MediaBrowser.Controller/Library/ItemResolveArgs.cs
index 01986d303..c70102167 100644
--- a/MediaBrowser.Controller/Library/ItemResolveArgs.cs
+++ b/MediaBrowser.Controller/Library/ItemResolveArgs.cs
@@ -1,12 +1,11 @@
 #nullable disable
 
-#pragma warning disable CA1721, CA1819, CS1591
+#pragma warning disable CS1591
 
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using MediaBrowser.Controller.Entities;
-using MediaBrowser.Controller.Providers;
 using MediaBrowser.Model.Configuration;
 using MediaBrowser.Model.IO;
 
@@ -23,22 +22,20 @@ namespace MediaBrowser.Controller.Library
         /// </summary>
         private readonly IServerApplicationPaths _appPaths;
 
+        private readonly ILibraryManager _libraryManager;
         private LibraryOptions _libraryOptions;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="ItemResolveArgs" /> class.
         /// </summary>
         /// <param name="appPaths">The app paths.</param>
-        /// <param name="directoryService">The directory service.</param>
-        public ItemResolveArgs(IServerApplicationPaths appPaths, IDirectoryService directoryService)
+        /// <param name="libraryManager">The library manager.</param>
+        public ItemResolveArgs(IServerApplicationPaths appPaths, ILibraryManager libraryManager)
         {
             _appPaths = appPaths;
-            DirectoryService = directoryService;
+            _libraryManager = libraryManager;
         }
 
-        // TODO remove dependencies as properties, they should be injected where it makes sense
-        public IDirectoryService DirectoryService { get; }
-
         /// <summary>
         /// Gets or sets the file system children.
         /// </summary>
@@ -47,7 +44,7 @@ namespace MediaBrowser.Controller.Library
 
         public LibraryOptions LibraryOptions
         {
-            get => _libraryOptions ??= Parent is null ? new LibraryOptions() : BaseItem.LibraryManager.GetLibraryOptions(Parent);
+            get => _libraryOptions ??= Parent is null ? new LibraryOptions() : _libraryManager.GetLibraryOptions(Parent);
             set => _libraryOptions = value;
         }
 
@@ -231,21 +228,15 @@ namespace MediaBrowser.Controller.Library
         /// <summary>
         /// Gets the configured content type for the path.
         /// </summary>
-        /// <remarks>
-        /// This is subject to future refactoring as it relies on a static property in BaseItem.
-        /// </remarks>
         /// <returns>The configured content type.</returns>
         public string GetConfiguredContentType()
         {
-            return BaseItem.LibraryManager.GetConfiguredContentType(Path);
+            return _libraryManager.GetConfiguredContentType(Path);
         }
 
         /// <summary>
         /// Gets the file system children that do not hit the ignore file check.
         /// </summary>
-        /// <remarks>
-        /// This is subject to future refactoring as it relies on a static property in BaseItem.
-        /// </remarks>
         /// <returns>The file system children that are not ignored.</returns>
         public IEnumerable<FileSystemMetadata> GetActualFileSystemChildren()
         {
@@ -253,7 +244,7 @@ namespace MediaBrowser.Controller.Library
             for (var i = 0; i < numberOfChildren; i++)
             {
                 var child = FileSystemChildren[i];
-                if (BaseItem.LibraryManager.IgnoreFile(child, Parent))
+                if (_libraryManager.IgnoreFile(child, Parent))
                 {
                     continue;
                 }
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/AudioResolverTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/AudioResolverTests.cs
new file mode 100644
index 000000000..d136c1bc6
--- /dev/null
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/AudioResolverTests.cs
@@ -0,0 +1,76 @@
+using System.Linq;
+using Emby.Naming.Common;
+using Emby.Server.Implementations.Library.Resolvers.Audio;
+using MediaBrowser.Controller.Entities.Audio;
+using MediaBrowser.Controller.Library;
+using MediaBrowser.Model.IO;
+using Moq;
+using Xunit;
+
+namespace Jellyfin.Server.Implementations.Tests.Library;
+
+public class AudioResolverTests
+{
+    private static readonly NamingOptions _namingOptions = new();
+
+    [Theory]
+    [InlineData("words.mp3")] // single non-tagged file
+    [InlineData("chapter 01.mp3")]
+    [InlineData("part 1.mp3")]
+    [InlineData("chapter 01.mp3", "non-media.txt")]
+    [InlineData("title.mp3", "title.epub")]
+    [InlineData("01.mp3", "subdirectory/")] // single media file with sub-directory - note that this will hide any contents in the subdirectory
+    public void Resolve_AudiobookDirectory_SingleResult(params string[] children)
+    {
+        var resolved = TestResolveChildren("/parent/title", children);
+        Assert.NotNull(resolved);
+    }
+
+    [Theory]
+    /* Results that can't be displayed as an audio book. */
+    [InlineData] // no contents
+    [InlineData("subdirectory/")]
+    [InlineData("non-media.txt")]
+    /* Names don't indicate parts of a single book. */
+    [InlineData("Name.mp3", "Another Name.mp3")]
+    /* Results that are an audio book but not currently navigable as such (multiple chapters and/or parts). */
+    [InlineData("01.mp3", "02.mp3")]
+    [InlineData("chapter 01.mp3", "chapter 02.mp3")]
+    [InlineData("part 1.mp3", "part 2.mp3")]
+    [InlineData("chapter 01 part 01.mp3", "chapter 01 part 02.mp3")]
+    /* Mismatched chapters, parts, and named files. */
+    [InlineData("chapter 01.mp3", "part 2.mp3")]
+    [InlineData("book title.mp3", "chapter name.mp3")] // "book title" resolves as alternate version of book based on directory name
+    [InlineData("01 Content.mp3", "01 Credits.mp3")] // resolves as alternate versions of chapter 1
+    [InlineData("Chapter Name.mp3", "Part 1.mp3")]
+    public void Resolve_AudiobookDirectory_NoResult(params string[] children)
+    {
+        var resolved = TestResolveChildren("/parent/book title", children);
+        Assert.Null(resolved);
+    }
+
+    private Audio? TestResolveChildren(string parent, string[] children)
+    {
+        var childrenMetadata = children.Select(name => new FileSystemMetadata
+        {
+            FullName = parent + "/" + name,
+            IsDirectory = name.EndsWith('/')
+        }).ToArray();
+
+        var resolver = new AudioResolver(_namingOptions);
+        var itemResolveArgs = new ItemResolveArgs(
+            null,
+            Mock.Of<ILibraryManager>())
+        {
+            CollectionType = "books",
+            FileInfo = new FileSystemMetadata
+            {
+                FullName = parent,
+                IsDirectory = true
+            },
+            FileSystemChildren = childrenMetadata
+        };
+
+        return resolver.Resolve(itemResolveArgs);
+    }
+}
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/EpisodeResolverTest.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/EpisodeResolverTest.cs
index 286ba0405..6d0ed7bbb 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Library/EpisodeResolverTest.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/EpisodeResolverTest.cs
@@ -22,10 +22,10 @@ namespace Jellyfin.Server.Implementations.Tests.Library
         {
             var parent = new Folder { Name = "extras" };
 
-            var episodeResolver = new EpisodeResolver(Mock.Of<ILogger<EpisodeResolver>>(), _namingOptions);
+            var episodeResolver = new EpisodeResolver(Mock.Of<ILogger<EpisodeResolver>>(), _namingOptions, Mock.Of<IDirectoryService>());
             var itemResolveArgs = new ItemResolveArgs(
                 Mock.Of<IServerApplicationPaths>(),
-                Mock.Of<IDirectoryService>())
+                null)
             {
                 Parent = parent,
                 CollectionType = CollectionType.TvShows,
@@ -45,10 +45,10 @@ namespace Jellyfin.Server.Implementations.Tests.Library
 
             // Have to create a mock because of moq proxies not being castable to a concrete implementation
             // https://github.com/jellyfin/jellyfin/blob/ab0cff8556403e123642dc9717ba778329554634/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs#L48
-            var episodeResolver = new EpisodeResolverMock(Mock.Of<ILogger<EpisodeResolver>>(), _namingOptions);
+            var episodeResolver = new EpisodeResolverMock(Mock.Of<ILogger<EpisodeResolver>>(), _namingOptions, Mock.Of<IDirectoryService>());
             var itemResolveArgs = new ItemResolveArgs(
                 Mock.Of<IServerApplicationPaths>(),
-                Mock.Of<IDirectoryService>())
+                null)
             {
                 Parent = series,
                 CollectionType = CollectionType.TvShows,
@@ -62,7 +62,7 @@ namespace Jellyfin.Server.Implementations.Tests.Library
 
         private sealed class EpisodeResolverMock : EpisodeResolver
         {
-            public EpisodeResolverMock(ILogger<EpisodeResolver> logger, NamingOptions namingOptions) : base(logger, namingOptions)
+            public EpisodeResolverMock(ILogger<EpisodeResolver> logger, NamingOptions namingOptions, IDirectoryService directoryService) : base(logger, namingOptions, directoryService)
             {
             }
 
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/MovieResolverTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/MovieResolverTests.cs
index efc3ac0c2..aed584355 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Library/MovieResolverTests.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/MovieResolverTests.cs
@@ -18,10 +18,10 @@ public class MovieResolverTests
     [Fact]
     public void Resolve_GivenLocalAlternateVersion_ResolvesToVideo()
     {
-        var movieResolver = new MovieResolver(Mock.Of<IImageProcessor>(), Mock.Of<ILogger<MovieResolver>>(), _namingOptions);
+        var movieResolver = new MovieResolver(Mock.Of<IImageProcessor>(), Mock.Of<ILogger<MovieResolver>>(), _namingOptions, Mock.Of<IDirectoryService>());
         var itemResolveArgs = new ItemResolveArgs(
             Mock.Of<IServerApplicationPaths>(),
-            Mock.Of<IDirectoryService>())
+            null)
         {
             Parent = null,
             FileInfo = new FileSystemMetadata