public ActionResult LogIn(string username, string password)
        {
            DatabaseInterface db = new DatabaseInterface();
             User user = db.GetUser(username, password);
             if (user == null)
             {
            return Json(new
            {
               error = true,
               message = "Invalid username or password"
            });
             }
             FormsAuthentication.SetAuthCookie(user.Id.ToString(), false);
             sessionManager.User = user;
             var model = new OutputViewModel()
             {
            Username = user.Username,
            Routes = db.GetAvailableRoutes(),
            Buses = db.GetAvailableBuses(),
            Employees = db.GetAvailableEmployees(),
            Stops = db.GetAvailableStops(),
            Drivers = db.GetAvailableDrivers()
             };

             return Json(new
             {
            user = JsonUtility.ToUserJson(user),
            headerText = "Welcome, " + model.Username,
            html = RenderPartialViewToString("AdminView", model)
             });
        }