async Task ProcessTrackingWorkItemAsync()

in src/DurableTask.ServiceBus/ServiceBusOrchestrationService.cs [1456:1520]
59 lines of code
8 McCabe index (conditional complexity)

        async Task ProcessTrackingWorkItemAsync(TrackingWorkItem workItem)
        {
            var sessionState = workItem.SessionInstance as ServiceBusOrchestrationSession;
            if (sessionState == null)
            {
                throw new ArgumentNullException(nameof(workItem.SessionInstance));
            }

            var historyEntities = new List<OrchestrationWorkItemInstanceEntity>();
            var stateEntities = new List<OrchestrationStateInstanceEntity>();

            foreach (TaskMessage taskMessage in workItem.NewMessages)
            {
                if (taskMessage.Event.EventType == EventType.HistoryState)
                {
                    stateEntities.Add(new OrchestrationStateInstanceEntity
                    {
                        State = (taskMessage.Event as HistoryStateEvent)?.State,
                        SequenceNumber = taskMessage.SequenceNumber
                    });
                }
                else
                {
                    historyEntities.Add(new OrchestrationWorkItemInstanceEntity
                    {
                        InstanceId = taskMessage.OrchestrationInstance.InstanceId,
                        ExecutionId = taskMessage.OrchestrationInstance.ExecutionId,
                        SequenceNumber = taskMessage.SequenceNumber,
                        EventTimestamp = DateTime.UtcNow,
                        HistoryEvent = taskMessage.Event
                    });
                }
            }

            TraceEntities(TraceEventType.Verbose, "Writing tracking history event", historyEntities, GetNormalizedWorkItemEvent);
            TraceEntities(TraceEventType.Verbose, "Writing tracking state event", stateEntities, GetNormalizedStateEvent);

            try
            {
                await this.InstanceStore.WriteEntitiesAsync(historyEntities);
            }
            catch (Exception e) when (!Utils.IsFatal(e))
            {
                TraceEntities(TraceEventType.Critical, $"Failed to write history entity: {e}", historyEntities, GetNormalizedWorkItemEvent);
                throw;
            }

            try
            {
                // TODO : send batch to instance store, it can write it as individual if it chooses
                foreach (OrchestrationStateInstanceEntity stateEntity in stateEntities)
                {
                    await this.InstanceStore.WriteEntitiesAsync(new List<OrchestrationStateInstanceEntity> { stateEntity });
                }
            }
            catch (Exception e) when (!Utils.IsFatal(e))
            {
                TraceEntities(TraceEventType.Critical, $"Failed to write state entity: {e}", stateEntities, GetNormalizedStateEvent);
                throw;
            }

            // Cleanup our session
            await sessionState.Session.CompleteAsync(sessionState.LockTokens.Values);
            await sessionState.Session.CloseAsync();
        }