private async Task SendNotificationImplAsync()

in src/Microsoft.Azure.NotificationHubs/NotificationHubClient.cs [3012:3077]
56 lines of code
6 McCabe index (conditional complexity)

        private async Task<NotificationOutcome> SendNotificationImplAsync(Notification notification, string tagExpression, string deviceHandle, CancellationToken cancellationToken)
        {
            var requestUri = GetGenericRequestUriBuilder();
            requestUri.Path += "messages";

            if (!string.IsNullOrWhiteSpace(deviceHandle))
            {
                AddToQuery(requestUri, "&direct");
            }

            // 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))
                {
                    if (!string.IsNullOrWhiteSpace(deviceHandle))
                    {
                        request.Headers.Add("ServiceBusNotification-DeviceHandle", deviceHandle);
                    }

                    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))
                    {
                        if (EnableTestSend)
                        {
                            using (var responseContent = await response.Content.ReadAsStreamAsync().ConfigureAwait(false))
                            using (var reader = XmlReader.Create(responseContent, new XmlReaderSettings { CloseInput = true }))
                            {
                                var result = (NotificationOutcome)_debugResponseSerializer.ReadObject(reader);
                                result.State = NotificationOutcomeState.DetailedStateAvailable;
                                result.TrackingId = trackingId;
                                return result;
                            }
                        }
                        else
                        {
                            var result = new NotificationOutcome
                            {
                                State = NotificationOutcomeState.Enqueued,
                                TrackingId = trackingId,
                                NotificationId = GetNotificationIdFromResponse(response)
                            };

                            return result;
                        }
                    }
                }
            }, cancellationToken);
        }