public async Task <ActionResult> Detail(int?id) { if (id == null || !_podcastService.PodcastExists((int)id)) { return(RedirectToAction("Index", "Home")); // TODO: redirect to error page } var userId = User.Identity.GetUserId(); var viewModel = await _mediator.Send(new Detail.Query { PodcastId = (int)id, UserId = userId }); return(View(viewModel)); }