private async Task GetSelectedRecommendationFromPreviousDeployment()

in src/AWS.Deploy.CLI/Commands/DeployCommand.cs [346:398]
46 lines of code
7 McCabe index (conditional complexity)

        private async Task<Recommendation> GetSelectedRecommendationFromPreviousDeployment(Orchestrator orchestrator, List<Recommendation> recommendations, CloudApplication deployedApplication, DeploymentSettings? deploymentSettings, string deploymentProjectPath)
        {
            var deploymentSettingRecipeId = deploymentSettings?.RecipeId;
            var selectedRecommendation = await GetRecommendationForRedeployment(recommendations, deployedApplication, deploymentProjectPath);
            if (selectedRecommendation == null)
            {
                var errorMessage = $"{deployedApplication.Name} already exists as a {deployedApplication.ResourceType} but a compatible recommendation used to perform a re-deployment was not found.";
                throw new FailedToFindCompatibleRecipeException(DeployToolErrorCode.CompatibleRecommendationForRedeploymentNotFound, errorMessage);
            }
            if (!string.IsNullOrEmpty(deploymentSettingRecipeId) && !string.Equals(deploymentSettingRecipeId, selectedRecommendation.Recipe.Id, StringComparison.InvariantCultureIgnoreCase))
            {
                var errorMessage = $"The existing {deployedApplication.ResourceType} {deployedApplication.Name} was created from a different deployment recommendation. " +
                    "Deploying to an existing target must be performed with the original deployment recommendation to avoid unintended destructive changes to the resources.";
                if (_toolInteractiveService.Diagnostics)
                {
                    errorMessage += Environment.NewLine + $"The original deployment recipe ID was {deployedApplication.RecipeId} and the current deployment recipe ID is {deploymentSettingRecipeId}";
                }
                throw new InvalidDeploymentSettingsException(DeployToolErrorCode.StackCreatedFromDifferentDeploymentRecommendation, errorMessage.Trim());
            }

            IDictionary<string, object> previousSettings;
            if (deployedApplication.ResourceType == CloudApplicationResourceType.CloudFormationStack)
            {
                var metadata = await _cloudFormationTemplateReader.LoadCloudApplicationMetadata(deployedApplication.Name);
                previousSettings = metadata.Settings.Union(metadata.DeploymentBundleSettings).ToDictionary(x => x.Key, x => x.Value);
            }
            else
            {
                previousSettings = await _deployedApplicationQueryer.GetPreviousSettings(deployedApplication, selectedRecommendation);
            }

            await orchestrator.ApplyAllReplacementTokens(selectedRecommendation, deployedApplication.Name);

            selectedRecommendation = await orchestrator.ApplyRecommendationPreviousSettings(selectedRecommendation, previousSettings);

            var header = $"Loading {deployedApplication.DisplayName} settings:";

            _toolInteractiveService.WriteLine(header);
            _toolInteractiveService.WriteLine(new string('-', header.Length));
            var optionSettings =
                selectedRecommendation
                    .Recipe
                    .OptionSettings
                    .Where(x => _optionSettingHandler.IsSummaryDisplayable(selectedRecommendation, x))
                    .ToArray();

            foreach (var setting in optionSettings)
            {
                DisplayOptionSetting(selectedRecommendation, setting, -1, optionSettings.Length, DisplayOptionSettingsMode.Readonly);
            }

            return selectedRecommendation;
        }