package software.amazon.applicationinsights.application;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.databind.MapperFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import software.amazon.applicationinsights.application.InputConfiguration.InputComponentConfiguration;
import software.amazon.awssdk.services.applicationinsights.ApplicationInsightsClient;
import software.amazon.awssdk.services.applicationinsights.model.ApplicationComponent;
import software.amazon.awssdk.services.applicationinsights.model.CreateApplicationRequest;
import software.amazon.awssdk.services.applicationinsights.model.CreateComponentRequest;
import software.amazon.awssdk.services.applicationinsights.model.CreateLogPatternRequest;
import software.amazon.awssdk.services.applicationinsights.model.DeleteApplicationRequest;
import software.amazon.awssdk.services.applicationinsights.model.DeleteComponentRequest;
import software.amazon.awssdk.services.applicationinsights.model.DeleteLogPatternRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeApplicationRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeApplicationResponse;
import software.amazon.awssdk.services.applicationinsights.model.DescribeComponentConfigurationRecommendationRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeComponentConfigurationRecommendationResponse;
import software.amazon.awssdk.services.applicationinsights.model.DescribeComponentConfigurationRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeComponentRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeComponentResponse;
import software.amazon.awssdk.services.applicationinsights.model.DescribeLogPatternRequest;
import software.amazon.awssdk.services.applicationinsights.model.DescribeLogPatternResponse;
import software.amazon.awssdk.services.applicationinsights.model.ListApplicationsRequest;
import software.amazon.awssdk.services.applicationinsights.model.ListApplicationsResponse;
import software.amazon.awssdk.services.applicationinsights.model.ListComponentsRequest;
import software.amazon.awssdk.services.applicationinsights.model.ListComponentsResponse;
import software.amazon.awssdk.services.applicationinsights.model.ListLogPatternsRequest;
import software.amazon.awssdk.services.applicationinsights.model.ListLogPatternsResponse;
import software.amazon.awssdk.services.applicationinsights.model.ListTagsForResourceRequest;
import software.amazon.awssdk.services.applicationinsights.model.ListTagsForResourceResponse;
import software.amazon.awssdk.services.applicationinsights.model.ResourceNotFoundException;
import software.amazon.awssdk.services.applicationinsights.model.Tag;
import software.amazon.awssdk.services.applicationinsights.model.TagResourceRequest;
import software.amazon.awssdk.services.applicationinsights.model.UntagResourceRequest;
import software.amazon.awssdk.services.applicationinsights.model.UpdateApplicationRequest;
import software.amazon.awssdk.services.applicationinsights.model.UpdateComponentConfigurationRequest;
import software.amazon.awssdk.services.applicationinsights.model.UpdateLogPatternRequest;
import software.amazon.cloudformation.proxy.AmazonWebServicesClientProxy;
import software.amazon.cloudformation.proxy.Logger;
import software.amazon.cloudformation.proxy.ResourceHandlerRequest;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.function.Function;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

public class HandlerHelper {
    private static final String DEFAULT_COMPONENT_CONFIG_MODE = "DEFAULT";
    private static final String CUSTOM_COMPONENT_CONFIG_MODE = "CUSTOM";
    private static final String DEFAULT_WITH_OVERWRITE_COMPONENT_CONFIG_MODE = "DEFAULT_WITH_OVERWRITE";
    private static final int MAX_COMPONENTS_PER_LIST_REQUEST = 40;
    private static final Pattern APPLICATION_INSIGHTS_APPLICATION_ARN_PATTERN = Pattern.compile("^arn:.*:applicationinsights:.*:[0-9]{12}:application/resource-group/(.*)");

    public static boolean doesApplicationExist(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        try {
            describeApplicationInsightsApplication(resourceGroupName, proxy, applicationInsightsClient);
            return true;
        } catch (ResourceNotFoundException e) {
            return false;
        }
    }

    public static void createApplicationInsightsApplication(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(CreateApplicationRequest.builder()
                        // required fields
                        .resourceGroupName(model.getResourceGroupName())
                        // optional fields
                        .opsCenterEnabled(model.getOpsCenterEnabled())
                        .opsItemSNSTopicArn(model.getOpsItemSNSTopicArn())
                        // enable CloudWatch Events monitoring automatically, if not specified by customer
                        .cweMonitorEnabled(model.getCWEMonitorEnabled() == null ? true : model.getCWEMonitorEnabled())
                        .tags(translateModelTagsToSdkTags(model.getTags()))
                        .autoCreate(model.getAutoConfigurationEnabled())
                        .groupingType(model.getGroupingType())
                        .autoConfigEnabled(model.getAutoConfigurationEnabled())
                        .build(),
                applicationInsightsClient::createApplication);
    }

    public static DescribeApplicationResponse describeApplicationInsightsApplication(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return proxy.injectCredentialsAndInvokeV2(DescribeApplicationRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .build(),
                applicationInsightsClient::describeApplication);
    }

    private static Set<Tag> translateModelTagsToSdkTags(
            final Collection<software.amazon.applicationinsights.application.Tag> modelTags) {
        return Optional.ofNullable(modelTags).orElse(Collections.emptySet())
                .stream()
                .map(tag -> Tag.builder().key(tag.getKey()).value(tag.getValue()).build())
                .collect(Collectors.toSet());
    }

    private static Set<software.amazon.applicationinsights.application.Tag> translateSdkTagsToModelTags(
            final Collection<Tag> sdkTags) {
        return Optional.ofNullable(sdkTags).orElse(Collections.emptySet())
                .stream()
                .map(tag -> software.amazon.applicationinsights.application.Tag.builder().key(tag.key()).value(tag.value()).build())
                .collect(Collectors.toSet());
    }

    public static void deleteApplicationInsightsApplication(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(DeleteApplicationRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .build(),
                applicationInsightsClient::deleteApplication);
    }

    public static void createCustomComponent(
            CustomComponent customComponent,
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(CreateComponentRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .componentName(customComponent.getComponentName())
                        .resourceList(customComponent.getResourceList())
                        .build(),
                applicationInsightsClient::createComponent);
    }

    public static boolean doesCustomComponentExist(
            String resourceGroupName,
            String componentName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        try {
            proxy.injectCredentialsAndInvokeV2(DescribeComponentRequest.builder()
                            .resourceGroupName(resourceGroupName)
                            .componentName(componentName)
                            .build(),
                    applicationInsightsClient::describeComponent);
            return true;
        } catch (ResourceNotFoundException e) {
            return false;
        }
    }

    public static void createLogPattern(
            String patternSetName,
            LogPattern logPattern,
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(CreateLogPatternRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .patternSetName(patternSetName)
                        .patternName(logPattern.getPatternName())
                        .pattern(logPattern.getPattern())
                        .rank(logPattern.getRank())
                        .build(),
                applicationInsightsClient::createLogPattern);
    }

    public static boolean doesLogPatternExist(
            String resourceGroupName,
            String patternSetName,
            String patternName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        try {
            proxy.injectCredentialsAndInvokeV2(DescribeLogPatternRequest.builder()
                            .resourceGroupName(resourceGroupName)
                            .patternSetName(patternSetName)
                            .patternName(patternName)
                            .build(),
                    applicationInsightsClient::describeLogPattern);
            return true;
        } catch (ResourceNotFoundException e) {
            return false;
        }
    }

    public static void createComponentConfiguration(
            ComponentMonitoringSetting componentMonitoringSetting,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) throws IOException {
        String mode = componentMonitoringSetting.getComponentConfigurationMode();
        String componentNameOrArn = getComponentNameOrARNFromComponentMonitoringSetting(componentMonitoringSetting);

        if (mode.equals(CUSTOM_COMPONENT_CONFIG_MODE)) {
            InputComponentConfiguration inputConfig =
                    new InputComponentConfiguration(componentMonitoringSetting.getCustomComponentConfiguration());

            ObjectMapper mapper = new ObjectMapper();
            mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
            String componentConfiguration = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(inputConfig);

            logger.log("Component name or ARN: " + componentNameOrArn);
            logger.log("Component Configuration String (CUSTOM mode): " + componentConfiguration);

            proxy.injectCredentialsAndInvokeV2(UpdateComponentConfigurationRequest.builder()
                            .resourceGroupName(model.getResourceGroupName())
                            .componentName(componentNameOrArn)
                            .monitor(true)
                            .tier(componentMonitoringSetting.getTier())
                            .componentConfiguration(componentConfiguration)
                            .build(),
                    applicationInsightsClient::updateComponentConfiguration);
        } else if (mode.equals(DEFAULT_COMPONENT_CONFIG_MODE)) {

            createDefaultComponentConfiguration(
                    componentNameOrArn, componentMonitoringSetting.getTier(), model, proxy, applicationInsightsClient, logger);

        } else if (mode.equals(DEFAULT_WITH_OVERWRITE_COMPONENT_CONFIG_MODE)) {
            DescribeComponentConfigurationRecommendationResponse describeComponentConfigurationRecommendationResponse =
                    proxy.injectCredentialsAndInvokeV2(DescribeComponentConfigurationRecommendationRequest.builder()
                                    .resourceGroupName(model.getResourceGroupName())
                                    .componentName(componentNameOrArn)
                                    .tier(componentMonitoringSetting.getTier())
                                    .build(),
                            applicationInsightsClient::describeComponentConfigurationRecommendation);

            logger.log("Component name or ARN: " + componentNameOrArn);
            String recomendedComponentConfigurationString =
                    describeComponentConfigurationRecommendationResponse.componentConfiguration();
            logger.log("Recommended Component Configuration String (DEFAULT_WITH_OVERWRITE mode): " + recomendedComponentConfigurationString);

            ObjectMapper mapper = new ObjectMapper()
                    .configure(MapperFeature.ACCEPT_CASE_INSENSITIVE_PROPERTIES, true)
                    .setSerializationInclusion(JsonInclude.Include.NON_NULL);
            InputComponentConfiguration recommendedInputConfig = mapper.readValue(
                    recomendedComponentConfigurationString, InputComponentConfiguration.class);

            logger.log("Recommended Component Configuration String transformed (DEFAULT_WITH_OVERWRITE mode): " +
                    mapper.writerWithDefaultPrettyPrinter().writeValueAsString(recommendedInputConfig));

            InputComponentConfiguration recommendedInputConfigWithOverwrite =
                    new InputComponentConfiguration(recommendedInputConfig, componentMonitoringSetting.getDefaultOverwriteComponentConfiguration());

            // Same as CUSTOM flow
            String componentConfiguration = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(recommendedInputConfigWithOverwrite);

            logger.log("Component Configuration String (DEFAULT_WITH_OVERWRITE mode): " + componentConfiguration);

            proxy.injectCredentialsAndInvokeV2(UpdateComponentConfigurationRequest.builder()
                            .resourceGroupName(model.getResourceGroupName())
                            .componentName(componentNameOrArn)
                            .monitor(true)
                            .tier(componentMonitoringSetting.getTier())
                            .componentConfiguration(componentConfiguration)
                            .build(),
                    applicationInsightsClient::updateComponentConfiguration);
        }
    }

    public static void createDefaultComponentConfiguration(
            String componentNameOrARN,
            String tier,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) throws IOException {
        DescribeComponentConfigurationRecommendationResponse describeComponentConfigurationRecommendationResponse =
                proxy.injectCredentialsAndInvokeV2(DescribeComponentConfigurationRecommendationRequest.builder()
                                .resourceGroupName(model.getResourceGroupName())
                                .componentName(componentNameOrARN)
                                .tier(tier)
                                .build(),
                        applicationInsightsClient::describeComponentConfigurationRecommendation);

        String recomendedComponentConfigurationString =
                describeComponentConfigurationRecommendationResponse.componentConfiguration();
        logger.log("Component name or ARN: " + componentNameOrARN);
        logger.log("Recommended Component Configuration String (DEFAULT mode): " + recomendedComponentConfigurationString);

        ObjectMapper mapper = new ObjectMapper()
                .configure(MapperFeature.ACCEPT_CASE_INSENSITIVE_PROPERTIES, true)
                .setSerializationInclusion(JsonInclude.Include.NON_NULL);
        InputComponentConfiguration recommendedInputConfig = mapper.readValue(
                recomendedComponentConfigurationString, InputComponentConfiguration.class);

        // same as CUSTOM branch
        String inputComponentConfigurationString = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(recommendedInputConfig);

        logger.log("Component Configuration String (DEFAULT mode): " + inputComponentConfigurationString);

        proxy.injectCredentialsAndInvokeV2(UpdateComponentConfigurationRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .componentName(componentNameOrARN)
                        .monitor(true)
                        .tier(tier)
                        .componentConfiguration(inputComponentConfigurationString)
                        .build(),
                applicationInsightsClient::updateComponentConfiguration);
    }

    public static String getComponentNameOrARNFromComponentMonitoringSetting(
            ComponentMonitoringSetting componentMonitoringSetting) {
        return componentMonitoringSetting.getComponentName() == null ?
                componentMonitoringSetting.getComponentARN() : componentMonitoringSetting.getComponentName();
    }

    public static List<String> getApplicationAllComponentNames(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<ApplicationComponent> appComponents = listApplicationComponents(model.getResourceGroupName(), proxy, applicationInsightsClient);

        return appComponents.stream()
            .map(applicationComponent -> applicationComponent.componentName())
            .collect(Collectors.toList());
    }

    public static void updateApplicationInsightsApplication(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(UpdateApplicationRequest.builder()
                        // required fields
                        .resourceGroupName(model.getResourceGroupName())
                        // optional fields
                        .opsCenterEnabled(model.getOpsCenterEnabled() == null ? false : model.getOpsCenterEnabled())
                        .opsItemSNSTopicArn(model.getOpsItemSNSTopicArn())
                        // enable CloudWatch Events monitoring automatically, if not specified by customer
                        .cweMonitorEnabled(model.getCWEMonitorEnabled() == null ? true : model.getCWEMonitorEnabled())
                        .removeSNSTopic(model.getOpsItemSNSTopicArn() == null ? true : false)
                        .autoConfigEnabled(model.getAutoConfigurationEnabled() == null ? false : model.getAutoConfigurationEnabled())
                        .build(),
                applicationInsightsClient::updateApplication);
    }

    public static List<String> getTagKeysToDelete(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        Set<Tag> appTags = new HashSet<>(getApplicationTags(model.getApplicationARN(), proxy, applicationInsightsClient));
        Set<Tag> modelTags = translateModelTagsToSdkTags(model.getTags());

        List<String> tagKeysToDelete = new ArrayList<>();

        for (Tag appTag : appTags) {
            if (!modelTags.contains(appTag)) {
                tagKeysToDelete.add(appTag.key());
            }
        }

        return tagKeysToDelete;
    }

    public static List<String> getTagKeysToCreate(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        Set<Tag> appTags = new HashSet<>(getApplicationTags(model.getApplicationARN(), proxy, applicationInsightsClient));
        Set<Tag> modelTags = translateModelTagsToSdkTags(model.getTags());

        List<String> tagKeysToCreate = new ArrayList<>();

        for (Tag modelTag : modelTags) {
            if (!appTags.contains(modelTag)) {
                tagKeysToCreate.add(modelTag.key());
            }
        }

        return tagKeysToCreate;
    }

    private static List<Tag> getApplicationTags(
            String applicationARN,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        ListTagsForResourceResponse response = proxy.injectCredentialsAndInvokeV2(ListTagsForResourceRequest.builder()
                        .resourceARN(applicationARN)
                        .build(),
                applicationInsightsClient::listTagsForResource);
        return response.tags();
    }

    public static void unTagApplication(
            String tagKeyToDelete,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        logger.log(String.format("Calling UntagResource API: %s %s", model.getApplicationARN(), tagKeyToDelete));
        proxy.injectCredentialsAndInvokeV2(UntagResourceRequest.builder()
                        .resourceARN(model.getApplicationARN())
                        .tagKeys(tagKeyToDelete)
                        .build(),
                applicationInsightsClient::untagResource);
        logger.log("Finish calling UntagResource API.");
    }

    public static boolean tagDeletedForApplicaiton(
            String tagKey,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        logger.log(String.format("Inside tagsDeletedForApplicaiton function for tagKey %s", tagKey));
        List<Tag> appTags = getApplicationTags(model.getApplicationARN(), proxy, applicationInsightsClient);

        for (Tag appTag : appTags) {
            if (tagKey.equals(appTag.key())) {
                return false;
            }
        }

        return true;
    }

    public static void tagApplication(
            String tagKeyToCreate,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        List<software.amazon.applicationinsights.application.Tag> tagsToCreate =
                Optional.ofNullable(model.getTags()).orElse(Collections.emptyList())
                        .stream()
                        .filter(tag -> tagKeyToCreate.equals(tag.getKey()))
                        .collect(Collectors.toList());

        logger.log(String.format("Calling TagResoruce API: %s %s", model.getApplicationARN(), translateModelTagsToSdkTags(tagsToCreate).toString()));
        proxy.injectCredentialsAndInvokeV2(TagResourceRequest.builder()
                        .resourceARN(model.getApplicationARN())
                        .tags(translateModelTagsToSdkTags(tagsToCreate))
                        .build(),
                applicationInsightsClient::tagResource);
        logger.log("Finish calling TagResoruce API.");
    }

    public static boolean tagCreatedForApplicaiton(
            String tagKey,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<Tag> appTags = getApplicationTags(model.getApplicationARN(), proxy, applicationInsightsClient);

        List<software.amazon.applicationinsights.application.Tag> tagsToCheck =
                Optional.ofNullable(model.getTags()).orElse(Collections.emptyList())
                        .stream()
                        .filter(tag -> tagKey.equals(tag.getKey()))
                        .collect(Collectors.toList());

        return appTags.containsAll(translateModelTagsToSdkTags(tagsToCheck));
    }

    public static List<String> getCustomComponentNamesToCreate(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        List<String> appComponentNames = getAppCustomComponentNames(model.getResourceGroupName(), proxy, applicationInsightsClient);
        logger.log("app component names: " + appComponentNames.toString());

        List<String> modelComponentNames =
                Optional.ofNullable(model.getCustomComponents()).orElse(Collections.emptyList())
                        .stream()
                        .map(customComponent -> customComponent.getComponentName())
                        .collect(Collectors.toList());
        logger.log("model component names: " + modelComponentNames.toString());

        List<String> componentNamesToCreate = new ArrayList<>(modelComponentNames);
        componentNamesToCreate.removeAll(appComponentNames);

        return componentNamesToCreate;
    }

    public static List<String> getCustomComponentNamesToDelete(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        List<String> appComponentNames = getAppCustomComponentNames(model.getResourceGroupName(), proxy, applicationInsightsClient);
        logger.log("app component names: " + appComponentNames.toString());

        Map<String, CustomComponent> modelComponentMap =
                Optional.ofNullable(model.getCustomComponents()).orElse(Collections.emptyList())
                        .stream()
                        .collect(Collectors.toMap(CustomComponent::getComponentName, Function.identity()));
        List<String> modelComponentNames = new ArrayList<>(modelComponentMap.keySet());
        logger.log("model component names: " + modelComponentNames.toString());

        List<String> componentNamesToDelete = new ArrayList<>(appComponentNames);
        componentNamesToDelete.removeAll(modelComponentNames);

        List<String> commonComponentNames = new ArrayList<>(appComponentNames);
        commonComponentNames.retainAll(modelComponentNames);
        logger.log("common component names: " + commonComponentNames.toString());

        for (String commonComponentName : commonComponentNames) {
            DescribeComponentResponse describeComponentResponse =
                    describeAppicationComponent(commonComponentName, model.getResourceGroupName(), proxy, applicationInsightsClient);
            List<String> resourceList = describeComponentResponse.resourceList();
            List<String> modelResourceList = modelComponentMap.get(commonComponentName).getResourceList();
            logger.log("common component name: " + commonComponentName);
            logger.log("app resource list: " + resourceList.toString());
            logger.log("model resource list: " + modelResourceList.toString());

            // if custom comopnent resource lists mistach, it needs to be deleted & recreated to avoid deadlock
            // e.g. before change: component A contains instance 1, component B contains instance 2;
            // after change: component A contains instance 2, component B contains instance 1
            if (resourceList.size() != modelResourceList.size() || !resourceList.containsAll(modelResourceList)) {
                componentNamesToDelete.add(commonComponentName);
            }
        }

        return componentNamesToDelete;
    }

    private static List<String> getAppCustomComponentNames(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<ApplicationComponent> appComponents = listApplicationComponents(resourceGroupName, proxy, applicationInsightsClient);
        return appComponents.stream()
                .filter(component -> component.resourceType().equals("CustomComponent"))
                .map(component -> component.componentName())
                .collect(Collectors.toList());
    }

    private static DescribeComponentResponse describeAppicationComponent(
            String componentName,
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return proxy.injectCredentialsAndInvokeV2(DescribeComponentRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .componentName(componentName)
                        .build(),
                applicationInsightsClient::describeComponent);
    }

    private static List<ApplicationComponent> listApplicationComponents(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<ApplicationComponent> appComponents = new ArrayList<>();
        String nextToken = null;

        do {
            ListComponentsResponse response = proxy.injectCredentialsAndInvokeV2(ListComponentsRequest.builder()
                    .resourceGroupName(resourceGroupName)
                    .maxResults(MAX_COMPONENTS_PER_LIST_REQUEST)
                    .nextToken(nextToken)
                    .build(),
                applicationInsightsClient::listComponents);

            if (response.applicationComponentList() != null) {
                appComponents.addAll(response.applicationComponentList());
            }
            nextToken = response.nextToken();
        } while (nextToken != null);

        return appComponents;
    }

    public static void deleteCustomComponent(
            String componentNameToDelete,
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(DeleteComponentRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .componentName(componentNameToDelete)
                        .build(),
                applicationInsightsClient::deleteComponent);
    }

    public static List<String> getLogPatternIdentifiersToDelete(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<String> appLogPatternIdentifiers = getAppLogPatternIdentifiers(model.getResourceGroupName(), proxy, applicationInsightsClient);

        List<String> modelLogPatternIdentifiers = getModelLogPatternIdentifiers(model);

        List<String> logPatternIdentifiersToDelete = new ArrayList<>(appLogPatternIdentifiers);
        logPatternIdentifiersToDelete.removeAll(modelLogPatternIdentifiers);

        return logPatternIdentifiersToDelete;
    }

    public static List<String> getLogPatternIdentifiersToCreate(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<String> appLogPatternIdentifiers = getAppLogPatternIdentifiers(model.getResourceGroupName(), proxy, applicationInsightsClient);

        List<String> modelLogPatternIdentifiers = getModelLogPatternIdentifiers(model);

        List<String> logPatternIdentifiersToCreate = new ArrayList<>(modelLogPatternIdentifiers);
        logPatternIdentifiersToCreate.removeAll(appLogPatternIdentifiers);

        return logPatternIdentifiersToCreate;
    }

    public static List<String> getLogPatternIdentifiersToUpdate(
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        List<String> appLogPatternIdentifiers = getAppLogPatternIdentifiers(model.getResourceGroupName(), proxy, applicationInsightsClient);

        List<String> modelLogPatternIdentifiers = getModelLogPatternIdentifiers(model);

        List<String> commonLogPatternIdentifiers = new ArrayList<>(appLogPatternIdentifiers);
        commonLogPatternIdentifiers.retainAll(modelLogPatternIdentifiers);

        List<String> logPatternIdentifiersToUpdate = new ArrayList<>();
        for (String commonLogPatternIdentifier : commonLogPatternIdentifiers) {
            if (!isLogPatternSyncedWithModel(
                    commonLogPatternIdentifier.split(":")[0],
                    commonLogPatternIdentifier.split(":")[1],
                    model,
                    proxy,
                    applicationInsightsClient)) {
                logPatternIdentifiersToUpdate.add(commonLogPatternIdentifier);
            }
        }

        return logPatternIdentifiersToUpdate;
    }

    private static List<String> getAppLogPatternIdentifiers(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return listLogPatterns(resourceGroupName, proxy, applicationInsightsClient).logPatterns().stream()
                .map(logPattern -> generateLogPatternIdentifier(logPattern.patternSetName(), logPattern.patternName()))
                .collect(Collectors.toList());
    }

    private static ListLogPatternsResponse listLogPatterns(
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return proxy.injectCredentialsAndInvokeV2(ListLogPatternsRequest.builder()
                        .resourceGroupName(resourceGroupName)
                        .build(),
                applicationInsightsClient::listLogPatterns);
    }

    public static void deleteLogPattern(
            String patternSetName,
            String patternName,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(DeleteLogPatternRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .patternSetName(patternSetName)
                        .patternName(patternName)
                        .build(),
                applicationInsightsClient::deleteLogPattern);
    }

    public static void updateLogPattern(
            String patternSetName,
            LogPattern logPattern,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        proxy.injectCredentialsAndInvokeV2(UpdateLogPatternRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .patternSetName(patternSetName)
                        .patternName(logPattern.getPatternName())
                        .pattern(logPattern.getPattern())
                        .rank(logPattern.getRank())
                        .build(),
                applicationInsightsClient::updateLogPattern);
    }

    public static boolean isLogPatternSyncedWithModel(
            String patternSetName,
            String patternName,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        DescribeLogPatternResponse describeLogPatternResponse =
                proxy.injectCredentialsAndInvokeV2(DescribeLogPatternRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .patternSetName(patternSetName)
                        .patternName(patternName)
                        .build(),
                applicationInsightsClient::describeLogPattern);

        LogPattern logPattern = pickLogPatternFromModel(patternSetName, patternName, model);

        if (!logPattern.getPattern().equals(describeLogPatternResponse.logPattern().pattern())) {
            return false;
        }

        if (!logPattern.getRank().equals(describeLogPatternResponse.logPattern().rank())) {
            return false;
        }

        return true;
    }

    public static LogPattern pickLogPatternFromModel(String patternSetName, String patternName, ResourceModel model) {
        if (model.getLogPatternSets() == null || model.getLogPatternSets().isEmpty()) {
            return null;
        }

        for (LogPatternSet logPatternSet : model.getLogPatternSets()) {
            if (logPatternSet.getPatternSetName().equals(patternSetName)) {
                for (LogPattern logPattern : logPatternSet.getLogPatterns()) {
                    if (logPattern.getPatternName().equals(patternName)) {
                        return logPattern;
                    }
                }
            }
        }

        return null;
    }

    public static String generateLogPatternIdentifier(
            String patternSetName,
            String patternName) {
        return String.format("%s:%s", patternSetName, patternName);
    }

    public static boolean isComponentConfigurationEnabled(
            String componentNameOrARN,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return proxy.injectCredentialsAndInvokeV2(DescribeComponentConfigurationRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .componentName(componentNameOrARN)
                        .build(),
                applicationInsightsClient::describeComponentConfiguration)
                .monitor();
    }

    public static void disableComponentConfiguration(
            String componentNameOrARN,
            ResourceModel model,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient,
            Logger logger) {
        proxy.injectCredentialsAndInvokeV2(UpdateComponentConfigurationRequest.builder()
                        .resourceGroupName(model.getResourceGroupName())
                        .componentName(componentNameOrARN)
                        .monitor(false)
                        .build(),
                applicationInsightsClient::updateComponentConfiguration);
    }

    public static ResourceModel generateReadModel(
            String resourceGroupName,
            ResourceModel model,
            ResourceHandlerRequest<ResourceModel> request,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        ResourceModel readModel = ResourceModel.builder().build();

        readModel.setResourceGroupName(resourceGroupName);

        readModel.setApplicationARN(String.format("arn:%s:applicationinsights:%s:%s:application/resource-group/%s",
                request.getAwsPartition(),
                request.getRegion(),
                request.getAwsAccountId(),
                resourceGroupName));

        // set readModel application level attributes
        DescribeApplicationResponse describeApplicationResponse = describeApplicationInsightsApplication(resourceGroupName, proxy, applicationInsightsClient);
        readModel.setCWEMonitorEnabled(model == null ? describeApplicationResponse.applicationInfo().cweMonitorEnabled() :
                getReadModelBooleanFromModel(model.getCWEMonitorEnabled(), describeApplicationResponse.applicationInfo().cweMonitorEnabled()));
        readModel.setOpsCenterEnabled(model == null ? describeApplicationResponse.applicationInfo().opsCenterEnabled() :
                getReadModelBooleanFromModel(model.getOpsCenterEnabled(), describeApplicationResponse.applicationInfo().opsCenterEnabled()));
        readModel.setOpsItemSNSTopicArn(describeApplicationResponse.applicationInfo().opsItemSNSTopicArn());

        // set readModel tags attribute
        List<Tag> appTags = getApplicationTags(readModel.getApplicationARN(), proxy, applicationInsightsClient);
        if (appTags != null && !appTags.isEmpty()) {
            readModel.setTags(new ArrayList<>(translateSdkTagsToModelTags(appTags)));
        }

        // set readModel customComponents attribute
        List<ApplicationComponent> appComponents = listApplicationComponents(resourceGroupName, proxy, applicationInsightsClient);
        List<ApplicationComponent> appCustomComponents = appComponents.stream()
                .filter(component -> component.resourceType().equals("CustomComponent"))
                .collect(Collectors.toList());
        if (appCustomComponents != null && !appCustomComponents.isEmpty()) {
            readModel.setCustomComponents(tanslateSdkCustomComponentsToModelCustomComponents(appCustomComponents, resourceGroupName, proxy, applicationInsightsClient));
        }

        // set readModel logPatternSets attribute
        ListLogPatternsResponse listLogPatternsResponse = listLogPatterns(resourceGroupName, proxy, applicationInsightsClient);
        List<LogPatternSet> appLogPatternSets = translateSdkLogPatternsToModelLogPatternSets(listLogPatternsResponse.logPatterns());
        if (appLogPatternSets != null && !appLogPatternSets.isEmpty()) {
            readModel.setLogPatternSets(appLogPatternSets);
        }

        return readModel;
    }

    private static List<LogPatternSet> translateSdkLogPatternsToModelLogPatternSets(
            List<software.amazon.awssdk.services.applicationinsights.model.LogPattern> logPatterns) {
        Map<String, List<software.amazon.awssdk.services.applicationinsights.model.LogPattern>> patternSetNamePatternsMap = new HashMap<>();
        for (software.amazon.awssdk.services.applicationinsights.model.LogPattern logPattern : logPatterns) {
            if (!patternSetNamePatternsMap.containsKey(logPattern.patternSetName())) {
                patternSetNamePatternsMap.put(logPattern.patternSetName(), new ArrayList<>(Arrays.asList(logPattern)));
            } else {
                patternSetNamePatternsMap.get(logPattern.patternSetName()).add(logPattern);
            }
        }

        List<LogPatternSet> modelLogPatternSets = new ArrayList<>();
        patternSetNamePatternsMap.entrySet().stream()
                .forEach(entry -> {
                    modelLogPatternSets.add(
                            LogPatternSet.builder()
                                    .patternSetName(entry.getKey())
                                    .logPatterns(entry.getValue().stream()
                                            .map(logPattern ->
                                                    LogPattern.builder()
                                                            .patternName(logPattern.patternName())
                                                            .rank(logPattern.rank())
                                                            .pattern(logPattern.pattern()).build())
                                            .collect(Collectors.toList()))
                                    .build());

                });

        return modelLogPatternSets;
    }

    private static List<CustomComponent> tanslateSdkCustomComponentsToModelCustomComponents(
            List<ApplicationComponent> appCustomComponents,
            String resourceGroupName,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return Optional.ofNullable(appCustomComponents).orElse(Collections.emptyList())
                .stream()
                .map(appCustomComponent -> CustomComponent.builder()
                        .componentName(appCustomComponent.componentName())
                        .resourceList(describeAppicationComponent(appCustomComponent.componentName(), resourceGroupName, proxy, applicationInsightsClient)
                                .resourceList())
                        .build())
                .collect(Collectors.toList());
    }

    private static Boolean getReadModelBooleanFromModel(Boolean modelBoolean, Boolean describeResponseBoolean) {
        return (!describeResponseBoolean && modelBoolean == null) ? null : describeResponseBoolean;
    }

    public static ListApplicationsResponse listApplicationInsightsApplications(
            String nextToken,
            AmazonWebServicesClientProxy proxy,
            ApplicationInsightsClient applicationInsightsClient) {
        return proxy.injectCredentialsAndInvokeV2(ListApplicationsRequest.builder()
                        .nextToken(nextToken)
                        .build(),
                applicationInsightsClient::listApplications);
    }

    public static List<String> getAllCustomComponentNamesToCreate(ResourceModel model) {
        return Optional.ofNullable(model.getCustomComponents()).orElse(Collections.emptyList())
                .stream()
                .map(customComponent -> customComponent.getComponentName())
                .collect(Collectors.toList());
    }

    public static List<String> getModelLogPatternIdentifiers(ResourceModel model) {
        List<String> logPatternIdentifiers = new ArrayList<>();

        if (model.getLogPatternSets() == null || model.getLogPatternSets().isEmpty()) {
            return logPatternIdentifiers;
        }

        for (LogPatternSet logPatternSet : model.getLogPatternSets()) {
            String patternSetName = logPatternSet.getPatternSetName();
            for (LogPattern logPattern : logPatternSet.getLogPatterns()) {
                String patternName = logPattern.getPatternName();
                logPatternIdentifiers.add(generateLogPatternIdentifier(patternSetName, patternName));
            }
        }

        return logPatternIdentifiers;
    }

    public static List<String> getAllComponentNamesWithMonitoringSettings(ResourceModel model, Logger logger) {
        return Optional.ofNullable(model.getComponentMonitoringSettings()).orElse(Collections.emptyList())
                .stream()
                .map(componentMonitoringSetting ->
                        HandlerHelper.getComponentNameOrARNFromComponentMonitoringSetting(componentMonitoringSetting))
                .collect(Collectors.toList());
    }

    public static boolean appNeedsUpdate(ResourceModel model, DescribeApplicationResponse response) {
        // CWEEnable = null from cfn model means its true by default.
        Boolean newCWEMonitorEnabled = model.getCWEMonitorEnabled() == null || model.getCWEMonitorEnabled();
        Boolean preCWEMonitorEnabled = response.applicationInfo().cweMonitorEnabled() != null && response.applicationInfo().cweMonitorEnabled();
        if (newCWEMonitorEnabled != preCWEMonitorEnabled) {
            return true;
        }

        Boolean newOpsCenterEnabled = model.getOpsCenterEnabled() != null && model.getOpsCenterEnabled();
        Boolean preOpsCenterEnabled = response.applicationInfo().opsCenterEnabled() != null && response.applicationInfo().opsCenterEnabled();
        if (newOpsCenterEnabled != preOpsCenterEnabled) {
            return true;
        }

        String newOpsItemSNSTopicArn = model.getOpsItemSNSTopicArn();
        String preOpsItemSNSTopicArn = response.applicationInfo().opsItemSNSTopicArn();

        if((newOpsItemSNSTopicArn == null && preOpsItemSNSTopicArn != null) ||
                (newOpsItemSNSTopicArn != null && preOpsItemSNSTopicArn == null)) {
            return true;
        }

        if (!((newOpsItemSNSTopicArn == null && preOpsItemSNSTopicArn == null) || newOpsItemSNSTopicArn.equals(preOpsItemSNSTopicArn))) {
            return true;
        }

        Boolean newAutoConfigurationEnable = model.getAutoConfigurationEnabled() != null && model.getAutoConfigurationEnabled();
        Boolean preAutoConfigurationEnable = response.applicationInfo().autoConfigEnabled() != null && response.applicationInfo().autoConfigEnabled();

        if (newAutoConfigurationEnable != preAutoConfigurationEnable) {
            return true;
        }

        return false;
    }

    public static String extractResourceGroupNameFromApplicationArn(final String applicationArn) {
        final Matcher matcher = APPLICATION_INSIGHTS_APPLICATION_ARN_PATTERN.matcher(applicationArn);
        matcher.matches();
        return matcher.group(1);
    }
}