private async Task SendScheduledNotificationImplAsync()

in src/Microsoft.Azure.NotificationHubs/NotificationHubClient.cs [3121:3172]
43 lines of code
4 McCabe index (conditional complexity)

        private async Task<ScheduledNotification> SendScheduledNotificationImplAsync(Notification notification, DateTimeOffset scheduledTime, string tagExpression, CancellationToken cancellationToken)
        {
            var requestUri = GetGenericRequestUriBuilder();
            requestUri.Path += "schedulednotifications";

            // Convert FcmNotification into GcmNotification
            notification = FcmToGcmNotificationTypeCast(notification);

            notification.ValidateAndPopulateHeaders();

            return await _retryPolicy.RunOperation(async (ct) =>
            {
                using (var request = CreateHttpRequest(HttpMethod.Post, requestUri.Uri, out var trackingId))
                {
                    request.Headers.Add("ServiceBusNotification-ScheduleTime", scheduledTime.UtcDateTime.ToString("s", CultureInfo.InvariantCulture));

                    if (!string.IsNullOrWhiteSpace(tagExpression))
                    {
                        request.Headers.Add("ServiceBusNotification-Tags", tagExpression);
                    }

                    foreach (var item in notification.Headers)
                    {
                        request.Headers.Add(item.Key, item.Value);
                    }

                    ParseContentType(notification.ContentType, out var mediaType, out var encoding);
                    request.Content = new StringContent(notification.Body, encoding, mediaType);
                    request.Content.Headers.ContentType = new MediaTypeHeaderValue(mediaType);

                    using (var response = await SendRequestAsync(request, trackingId, new[] { HttpStatusCode.OK, HttpStatusCode.Created }, ct).ConfigureAwait(false))
                    {
                        string notificationId = null;
                        if (response.Headers.Location != null)
                        {
                            notificationId = response.Headers.Location.Segments.Last().Trim('/');
                        }

                        var result = new ScheduledNotification()
                        {
                            ScheduledNotificationId = notificationId,
                            Tags = tagExpression,
                            ScheduledTime = scheduledTime,
                            Payload = notification,
                            TrackingId = trackingId
                        };

                        return result;
                    }
                }
            }, cancellationToken);
        }