4 files changed, 45 insertions, 24 deletions
diff --git a/MediaBrowser.Controller/Entities/BaseItem.cs b/MediaBrowser.Controller/Entities/BaseItem.cs
index 5f1d45fc8..072555986 100644
--- a/MediaBrowser.Controller/Entities/BaseItem.cs
+++ b/MediaBrowser.Controller/Entities/BaseItem.cs
@@ -53,16 +53,6 @@ namespace MediaBrowser.Controller.Entities
         public static string ThemeSongFilename = "theme";
         public static string ThemeVideosFolderName = "backdrops";
 
-        public static List<KeyValuePair<string, ExtraType>> ExtraSuffixes = new List<KeyValuePair<string, ExtraType>>
-        {
-            new KeyValuePair<string,ExtraType>("-trailer", ExtraType.Trailer),
-            new KeyValuePair<string,ExtraType>("-deleted", ExtraType.DeletedScene),
-            new KeyValuePair<string,ExtraType>("-behindthescenes", ExtraType.BehindTheScenes),
-            new KeyValuePair<string,ExtraType>("-interview", ExtraType.Interview),
-            new KeyValuePair<string,ExtraType>("-scene", ExtraType.Scene),
-            new KeyValuePair<string,ExtraType>("-sample", ExtraType.Sample)
-        };
-
         public List<ItemImageInfo> ImageInfos { get; set; }
 
         [IgnoreDataMember]
@@ -618,7 +608,9 @@ namespace MediaBrowser.Controller.Entities
                 .Where(i => string.Equals(FileSystem.GetFileNameWithoutExtension(i), ThemeSongFilename, StringComparison.OrdinalIgnoreCase))
                 );
 
-            return LibraryManager.ResolvePaths<Audio.Audio>(files, directoryService, null).Select(audio =>
+            return LibraryManager.ResolvePaths(files, directoryService, null)
+                .OfType<Audio.Audio>()
+                .Select(audio =>
             {
                 // Try to retrieve it from the db. If we don't find it, use the resolved version
                 var dbItem = LibraryManager.GetItemById(audio.Id) as Audio.Audio;
@@ -628,10 +620,7 @@ namespace MediaBrowser.Controller.Entities
                     audio = dbItem;
                 }
 
-                if (audio != null)
-                {
-                    audio.ExtraType = ExtraType.ThemeSong;
-                }
+                audio.ExtraType = ExtraType.ThemeSong;
 
                 return audio;
 
@@ -649,7 +638,9 @@ namespace MediaBrowser.Controller.Entities
                 .Where(i => string.Equals(i.Name, ThemeVideosFolderName, StringComparison.OrdinalIgnoreCase))
                 .SelectMany(i => i.EnumerateFiles("*", SearchOption.TopDirectoryOnly));
 
-            return LibraryManager.ResolvePaths<Video>(files, directoryService, null).Select(item =>
+            return LibraryManager.ResolvePaths(files, directoryService, null)
+                .OfType<Video>()
+                .Select(item =>
             {
                 // Try to retrieve it from the db. If we don't find it, use the resolved version
                 var dbItem = LibraryManager.GetItemById(item.Id) as Video;
@@ -659,10 +650,7 @@ namespace MediaBrowser.Controller.Entities
                     item = dbItem;
                 }
 
-                if (item != null)
-                {
-                    item.ExtraType = ExtraType.ThemeVideo;
-                }
+                item.ExtraType = ExtraType.ThemeVideo;
 
                 return item;
 
diff --git a/MediaBrowser.Controller/Entities/Folder.cs b/MediaBrowser.Controller/Entities/Folder.cs
index 8afa376b3..288972d7c 100644
--- a/MediaBrowser.Controller/Entities/Folder.cs
+++ b/MediaBrowser.Controller/Entities/Folder.cs
@@ -696,7 +696,7 @@ namespace MediaBrowser.Controller.Entities
         {
             var collectionType = LibraryManager.FindCollectionType(this);
 
-            return LibraryManager.ResolvePaths<BaseItem>(GetFileSystemChildren(directoryService), directoryService, this, collectionType);
+            return LibraryManager.ResolvePaths(GetFileSystemChildren(directoryService), directoryService, this, collectionType);
         }
 
         /// <summary>
@@ -741,6 +741,12 @@ namespace MediaBrowser.Controller.Entities
 
         private BaseItem RetrieveChild(BaseItem child)
         {
+            if (child.Id == Guid.Empty)
+            {
+                Logger.Error("Item found with empty Id: " + (child.Path ?? child.Name));
+                return null;
+            }
+
             var item = LibraryManager.GetMemoryItemById(child.Id);
 
             if (item != null)
diff --git a/MediaBrowser.Controller/Library/ILibraryManager.cs b/MediaBrowser.Controller/Library/ILibraryManager.cs
index d20c611ad..33dea4dca 100644
--- a/MediaBrowser.Controller/Library/ILibraryManager.cs
+++ b/MediaBrowser.Controller/Library/ILibraryManager.cs
@@ -24,7 +24,9 @@ namespace MediaBrowser.Controller.Library
         /// <param name="parent">The parent.</param>
         /// <param name="collectionType">Type of the collection.</param>
         /// <returns>BaseItem.</returns>
-        BaseItem ResolvePath(FileSystemInfo fileInfo, Folder parent = null, string collectionType = null);
+        BaseItem ResolvePath(FileSystemInfo fileInfo, 
+            Folder parent = null, 
+            string collectionType = null);
 
         /// <summary>
         /// Resolves a set of files into a list of BaseItem
@@ -35,8 +37,10 @@ namespace MediaBrowser.Controller.Library
         /// <param name="parent">The parent.</param>
         /// <param name="collectionType">Type of the collection.</param>
         /// <returns>List{``0}.</returns>
-        List<T> ResolvePaths<T>(IEnumerable<FileSystemInfo> files, IDirectoryService directoryService, Folder parent, string collectionType = null)
-            where T : BaseItem;
+        IEnumerable<BaseItem> ResolvePaths(IEnumerable<FileSystemInfo> files, 
+            IDirectoryService directoryService,
+            Folder parent, string 
+            collectionType = null);
 
         /// <summary>
         /// Gets the root folder.
diff --git a/MediaBrowser.Controller/Resolvers/IItemResolver.cs b/MediaBrowser.Controller/Resolvers/IItemResolver.cs
index 780d5d013..fec6be55c 100644
--- a/MediaBrowser.Controller/Resolvers/IItemResolver.cs
+++ b/MediaBrowser.Controller/Resolvers/IItemResolver.cs
@@ -1,5 +1,8 @@
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Providers;
+using System.Collections.Generic;
+using System.IO;
 
 namespace MediaBrowser.Controller.Resolvers
 {
@@ -20,4 +23,24 @@ namespace MediaBrowser.Controller.Resolvers
         /// <value>The priority.</value>
         ResolverPriority Priority { get; }
     }
+
+    public interface IMultiItemResolver
+    {
+        MultiItemResolverResult ResolveMultiple(Folder parent, 
+            List<FileSystemInfo> files, 
+            string collectionType,
+            IDirectoryService directoryService);
+    }
+
+    public class MultiItemResolverResult
+    {
+        public List<BaseItem> Items { get; set; }
+        public List<FileSystemInfo> ExtraFiles { get; set; }
+
+        public MultiItemResolverResult()
+        {
+            Items = new List<BaseItem>();
+            ExtraFiles = new List<FileSystemInfo>();
+        }
+    }
 }