Implement syncplay backend

MediaBrowser.Controller/Syncplay/ISyncplayController.cs

@@ -0,0 +1,61 @@
+using System;
+using MediaBrowser.Controller.Session;
+using MediaBrowser.Model.Syncplay;
+
+namespace MediaBrowser.Controller.Syncplay
+{
+    /// <summary>
+    /// Interface ISyncplayController.
+    /// </summary>
+    public interface ISyncplayController
+    {
+        /// <summary>
+        /// Gets the group id.
+        /// </summary>
+        /// <value>The group id.</value>
+        Guid GetGroupId();
+
+        /// <summary>
+        /// Gets the playing item id.
+        /// </summary>
+        /// <value>The playing item id.</value>
+        Guid GetPlayingItemId();
+
+        /// <summary>
+        /// Checks if the group is empty.
+        /// </summary>
+        /// <value>If the group is empty.</value>
+        bool IsGroupEmpty();
+
+        /// <summary>
+        /// Initializes the group with the user's info.
+        /// </summary>
+        /// <param name="user">The session.</param>
+        void InitGroup(SessionInfo user);
+
+        /// <summary>
+        /// Adds the user to the group.
+        /// </summary>
+        /// <param name="user">The session.</param>
+        void UserJoin(SessionInfo user);
+
+        /// <summary>
+        /// Removes the user from the group.
+        /// </summary>
+        /// <param name="user">The session.</param>
+        void UserLeave(SessionInfo user);
+
+        /// <summary>
+        /// Handles the requested action by the user.
+        /// </summary>
+        /// <param name="user">The session.</param>
+        /// <param name="request">The requested action.</param>
+        void HandleRequest(SessionInfo user, SyncplayRequestInfo request);
+
+        /// <summary>
+        /// Gets the info about the group for the clients.
+        /// </summary>
+        /// <value>The group info for the clients.</value>
+        GroupInfoView GetInfo();
+    }
+}