1 files changed, 100 insertions, 0 deletions
diff --git a/MediaBrowser.Controller/Entities/CollectionFolder.cs b/MediaBrowser.Controller/Entities/CollectionFolder.cs
new file mode 100644
index 000000000..5684f8e80
--- /dev/null
+++ b/MediaBrowser.Controller/Entities/CollectionFolder.cs
@@ -0,0 +1,100 @@
+using MediaBrowser.Common.Extensions;
+using MediaBrowser.Common.Logging;
+using MediaBrowser.Model.Tasks;
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Runtime.Serialization;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace MediaBrowser.Controller.Entities
+{
+    /// <summary>
+    /// Specialized Folder class that points to a subset of the physical folders in the system.
+    /// It is created from the user-specific folders within the system root
+    /// </summary>
+    public class CollectionFolder : Folder, ICollectionFolder
+    {
+        /// <summary>
+        /// Gets a value indicating whether this instance is virtual folder.
+        /// </summary>
+        /// <value><c>true</c> if this instance is virtual folder; otherwise, <c>false</c>.</value>
+        [IgnoreDataMember]
+        public override bool IsVirtualFolder
+        {
+            get
+            {
+                return true;
+            }
+        }
+
+        /// <summary>
+        /// Allow different display preferences for each collection folder
+        /// </summary>
+        /// <value>The display prefs id.</value>
+        public override Guid DisplayPrefsId
+        {
+            get
+            {
+                return Id;
+            }
+        }
+
+        // Cache this since it will be used a lot
+        /// <summary>
+        /// The null task result
+        /// </summary>
+        private static readonly Task NullTaskResult = Task.FromResult<object>(null);
+
+        /// <summary>
+        /// Compare our current children (presumably just read from the repo) with the current state of the file system and adjust for any changes
+        /// ***Currently does not contain logic to maintain items that are unavailable in the file system***
+        /// </summary>
+        /// <param name="progress">The progress.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <param name="recursive">if set to <c>true</c> [recursive].</param>
+        /// <returns>Task.</returns>
+        protected override Task ValidateChildrenInternal(IProgress<TaskProgress> progress, CancellationToken cancellationToken, bool? recursive = null)
+        {
+            //we don't directly validate our children
+            //but we do need to clear out the index cache...
+            IndexCache = new ConcurrentDictionary<string, List<BaseItem>>(StringComparer.OrdinalIgnoreCase);
+
+            return NullTaskResult;
+        }
+
+        /// <summary>
+        /// Our children are actually just references to the ones in the physical root...
+        /// </summary>
+        /// <value>The actual children.</value>
+        protected override ConcurrentBag<BaseItem> ActualChildren
+        {
+            get
+            {
+                IEnumerable<Guid> folderIds;
+
+                try
+                {
+                    // Accessing ResolveArgs could involve file system access
+                    folderIds = ResolveArgs.PhysicalLocations.Select(f => (f.GetMBId(typeof(Folder))));
+                }
+                catch (IOException ex)
+                {
+                    Logger.LogException("Error creating FolderIds for {0}", ex, Path);
+
+                    folderIds = new Guid[] {};
+                }
+
+                var ourChildren =
+                    Kernel.Instance.RootFolder.Children.OfType<Folder>()
+                          .Where(i => folderIds.Contains(i.Id))
+                          .SelectMany(c => c.Children);
+
+                return new ConcurrentBag<BaseItem>(ourChildren);
+            }
+        }
+    }
+}