support more kinds of remote control besides web socket

MediaBrowser.Server.Implementations/Session/WebSocketController.cs

@@ -0,0 +1,52 @@
+using MediaBrowser.Controller.Session;
+using MediaBrowser.Model.Logging;
+using MediaBrowser.Model.Net;
+using MediaBrowser.Model.Session;
+using System;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace MediaBrowser.Server.Implementations.Session
+{
+    public class WebSocketController : ISessionRemoteController
+    {
+        private readonly ILogger _logger;
+
+        public WebSocketController(ILogger logger)
+        {
+            _logger = logger;
+        }
+
+        public bool Supports(SessionInfo session)
+        {
+            return session.WebSockets.Any(i => i.State == WebSocketState.Open);
+        }
+
+        public async Task SendSystemCommand(SessionInfo session, SystemCommand command, CancellationToken cancellationToken)
+        {
+            var socket = session.WebSockets.OrderByDescending(i => i.LastActivityDate).FirstOrDefault(i => i.State == WebSocketState.Open);
+
+            if (socket != null)
+            {
+                try
+                {
+                    await socket.SendAsync(new WebSocketMessage<string>
+                    {
+                        MessageType = "SystemCommand",
+                        Data = command.ToString()
+
+                    }, cancellationToken).ConfigureAwait(false);
+                }
+                catch (Exception ex)
+                {
+                    _logger.ErrorException("Error sending web socket message", ex);
+                }
+            }
+            else
+            {
+                throw new InvalidOperationException("The requested session does not have an open web socket.");
+            }
+        }
+    }
+}