private async Task WaitForDeploymentCompletionAsync()

in src/Amazon.ElasticBeanstalk.Tools/Commands/DeployEnvironmentCommand.cs [650:708]
49 lines of code
11 McCabe index (conditional complexity)

        private async Task<bool> WaitForDeploymentCompletionAsync(string applicationName, string environmentName, DateTime startingEventDate)
        {
            var requestEnvironment = new DescribeEnvironmentsRequest
            {
                ApplicationName = applicationName,
                EnvironmentNames = new List<string> { environmentName }
            };

            var requestEvents = new DescribeEventsRequest
            {
                ApplicationName = applicationName,
                EnvironmentName = environmentName,
                StartTimeUtc = startingEventDate
            };

            var success = true;
            var lastPrintedEventDate = startingEventDate;
            EnvironmentDescription environment = new EnvironmentDescription();
            do
            {
                Thread.Sleep(5000);

                var responseEnvironments = await this.EBClient.DescribeEnvironmentsAsync(requestEnvironment);
                if (responseEnvironments.Environments.Count == 0)
                    throw new ElasticBeanstalkExceptions("Failed to find environment when waiting for deployment completion", ElasticBeanstalkExceptions.EBCode.FailedToFindEnvironment );

                environment = responseEnvironments.Environments[0];

                requestEvents.StartTimeUtc = lastPrintedEventDate;
                var responseEvents = await this.EBClient.DescribeEventsAsync(requestEvents);
                if(responseEvents.Events.Count > 0)
                {
                    for(int i = responseEvents.Events.Count - 1; i >= 0; i--)
                    {
                        var evnt = responseEvents.Events[i];
                        if (evnt.EventDate <= lastPrintedEventDate)
                            continue;

                        this.Logger?.WriteLine(evnt.EventDate.ToLocalTime() + "    " + evnt.Severity + "    " + evnt.Message);
                        if(evnt.Message.StartsWith("Failed to deploy application", StringComparison.OrdinalIgnoreCase) ||
                           evnt.Message.StartsWith("Failed to launch environment", StringComparison.OrdinalIgnoreCase) ||
                           evnt.Message.StartsWith("Error occurred during build: Command hooks failed", StringComparison.OrdinalIgnoreCase))
                        {
                            success = false;
                        }
                    }

                    lastPrintedEventDate = responseEvents.Events[0].EventDate;
                }

            } while (environment.Status == EnvironmentStatus.Launching || environment.Status == EnvironmentStatus.Updating);

            if(success)
            {
                this.Logger?.WriteLine("Environment update complete: http://{0}/", environment.EndpointURL);
            }

            return success;
        }