PeerCastStation.UI.HTTP.HTMLHost.OnRedirect C# (CSharp) Метод

    private async Task OnRedirect(IDictionary<string, object> owinenv)
    {
      var env = new OWINEnv(owinenv);
      var cancel_token = env.CallCanlelled;
      try {
        if (!HTTPUtils.CheckAuthorization(env.GetAuthorizationToken(), env.AccessControlInfo)) {
          throw new HTTPError(HttpStatusCode.Unauthorized);
        }
        if (env.RequestMethod!="HEAD" && env.RequestMethod!="GET") {
          throw new HTTPError(HttpStatusCode.MethodNotAllowed);
        }
        await SendResponseMoveToIndex(env, cancel_token);
      }
      catch (HTTPError err) {
        env.ResponseStatusCode = (int)err.StatusCode;
      }
      catch (UnauthorizedAccessException) {
        env.ResponseStatusCode = (int)HttpStatusCode.Forbidden;
      }
    }