void INotificationService.JoinRoom(ChatUser user, ChatRoom room)
        {
            var userViewModel = new UserViewModel(user);
            var roomViewModel = new RoomViewModel
            {
                Name = room.Name,
                Private = room.Private,
                Welcome = ConvertUrlsAndRoomLinks(room.Welcome ?? ""),
                Closed = room.Closed
            };

            var isOwner = user.OwnedRooms.Contains(room);

            // Tell all clients to join this room
            foreach (var client in user.ConnectedClients)
            {
                Clients[client.Id].joinRoom(roomViewModel);
            }

            // Tell the people in this room that you've joined
            Clients[room.Name].addUser(userViewModel, room.Name, isOwner).Wait();

            // Notify users of the room count change
            OnRoomChanged(room);

            foreach (var client in user.ConnectedClients)
            {
                // Add the caller to the group so they receive messages
                Groups.Add(client.Id, room.Name).Wait();
            }
        }

        private void OnRoomChanged(ChatRoom room)
        {
            var roomViewModel = new RoomViewModel
            {
                Name = room.Name,
                Private = room.Private,
                Closed = room.Closed
            };

            // Update the room count
            Clients.updateRoomCount(roomViewModel, _repository.GetOnlineUsers(room).Count());
        }

        void INotificationService.JoinRoom(ChatUser user, ChatRoom room)
        {
            var userViewModel = new UserViewModel(user);
            var roomViewModel = new RoomViewModel
            {
                Name = room.Name,
                Private = room.Private,
                Welcome = room.Welcome ?? "",
                Closed = room.Closed
            };

            var isOwner = user.OwnedRooms.Contains(room);

            // Tell all clients to join this room
            foreach (var client in user.ConnectedClients)
            {
                Clients.Client(client.Id).joinRoom(roomViewModel);
            }

            // Tell the people in this room that you've joined
            Clients.Group(room.Name).addUser(userViewModel, room.Name, isOwner).Wait();

            // Notify users of the room count change
            OnRoomChanged(room);

            foreach (var client in user.ConnectedClients)
            {
                Groups.Add(client.Id, room.Name);
            }
        }

 void INotificationService.ChangeTopic(ChatUser user, ChatRoom room)
 {
     bool isTopicCleared = String.IsNullOrWhiteSpace(room.Topic);
     var parsedTopic = ConvertUrlsAndRoomLinks(room.Topic ?? "");
     foreach (var client in user.ConnectedClients)
     {
         Clients[client.Id].topicChanged(isTopicCleared, parsedTopic);
     }
     // Create the view model
     var roomViewModel = new RoomViewModel
     {
         Name = room.Name,
         Topic = parsedTopic,
         Closed = room.Closed
     };
     Clients[room.Name].changeTopic(roomViewModel);
 }

 void INotificationService.ChangeTopic(ChatUser user, ChatRoom room)
 {
     bool isTopicCleared = String.IsNullOrWhiteSpace(room.Topic);
     var parsedTopic = room.Topic ?? "";
     Clients.Group(room.Name).topicChanged(room.Name, isTopicCleared, parsedTopic, user.Name);
     // Create the view model
     var roomViewModel = new RoomViewModel
     {
         Name = room.Name,
         Topic = parsedTopic,
         Closed = room.Closed
     };
     Clients.Group(room.Name).changeTopic(roomViewModel);
 }

        private void OnRoomChanged(ChatRoom room)
        {
            var roomViewModel = new RoomViewModel
            {
                Name = room.Name,
                Private = room.Private
            };

            // Update the room count
            Clients.updateRoomCount(roomViewModel, room.Users.Online().Count());
        }

        void INotificationService.AllowUser(ChatUser targetUser, ChatRoom targetRoom)
        {
            // Build a viewmodel for the room
            var roomViewModel = new RoomViewModel
            {
                Name = targetRoom.Name,
                Private = targetRoom.Private,
                Closed = targetRoom.Closed,
                Topic = targetRoom.Topic ?? String.Empty,
                Count = _repository.GetOnlineUsers(targetRoom).Count()
            };

            // Tell this client it's allowed.  Pass down a viewmodel so that we can add the room to the lobby.
            Clients.User(targetUser.Id).allowUser(targetRoom.Name, roomViewModel);

            // Tell the calling client the granting permission into the room was successful
            Clients.Caller.userAllowed(targetUser.Name, targetRoom.Name);
        }

        private void OnRoomChanged(ChatRoom room)
        {
            var roomViewModel = new RoomViewModel
            {
                Name = room.Name,
                Private = room.Private,
                Closed = room.Closed,
                Topic = room.Topic ?? String.Empty,
                Count = _repository.GetOnlineUsers(room).Count()
            };

            // notify all clients who can see the room
            if (!room.Private)
            {
                Clients.All.updateRoom(roomViewModel);
            }
            else
            {
                Clients.Clients(_repository.GetAllowedClientIds(room)).updateRoom(roomViewModel);
            }
        }

 void INotificationService.ChangeTopic(ChatUser user, ChatRoom room)
 {
     bool isTopicCleared = String.IsNullOrWhiteSpace(room.Topic);
     var parsedTopic = TextTransform.TransformAndParseUrls(_repository, room.Topic ?? "");
     foreach (var client in user.ConnectedClients)
     {
         Clients[client.Id].topicChanged(isTopicCleared, parsedTopic);
     }
     // Create the view model
     var roomViewModel = new RoomViewModel
     {
         Name = room.Name,
         Topic = parsedTopic
     };
     Clients[room.Name].changeTopic(roomViewModel);
 }