package application

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"math"
	"reflect"
	"sort"
	"strconv"
	"strings"
	"time"

	kubecache "github.com/argoproj/gitops-engine/pkg/cache"
	"github.com/argoproj/gitops-engine/pkg/diff"
	"github.com/argoproj/gitops-engine/pkg/sync/common"
	"github.com/argoproj/gitops-engine/pkg/utils/kube"
	"github.com/argoproj/gitops-engine/pkg/utils/text"
	"github.com/argoproj/pkg/sync"
	jsonpatch "github.com/evanphx/json-patch"
	log "github.com/sirupsen/logrus"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
	v1 "k8s.io/api/core/v1"
	apierr "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	"k8s.io/apimachinery/pkg/fields"
	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/apimachinery/pkg/watch"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/rest"
	"k8s.io/client-go/tools/cache"
	"k8s.io/utils/ptr"

	argocommon "github.com/argoproj/argo-cd/v2/common"
	"github.com/argoproj/argo-cd/v2/pkg/apiclient/application"
	"github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
	appv1 "github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
	appclientset "github.com/argoproj/argo-cd/v2/pkg/client/clientset/versioned"
	applisters "github.com/argoproj/argo-cd/v2/pkg/client/listers/application/v1alpha1"
	"github.com/argoproj/argo-cd/v2/reposerver/apiclient"
	servercache "github.com/argoproj/argo-cd/v2/server/cache"
	"github.com/argoproj/argo-cd/v2/server/deeplinks"
	"github.com/argoproj/argo-cd/v2/server/rbacpolicy"
	"github.com/argoproj/argo-cd/v2/util/argo"
	argoutil "github.com/argoproj/argo-cd/v2/util/argo"
	"github.com/argoproj/argo-cd/v2/util/collections"
	"github.com/argoproj/argo-cd/v2/util/db"
	"github.com/argoproj/argo-cd/v2/util/env"
	"github.com/argoproj/argo-cd/v2/util/git"
	ioutil "github.com/argoproj/argo-cd/v2/util/io"
	"github.com/argoproj/argo-cd/v2/util/lua"
	"github.com/argoproj/argo-cd/v2/util/manifeststream"
	"github.com/argoproj/argo-cd/v2/util/rbac"
	"github.com/argoproj/argo-cd/v2/util/security"
	"github.com/argoproj/argo-cd/v2/util/session"
	"github.com/argoproj/argo-cd/v2/util/settings"

	applicationType "github.com/argoproj/argo-cd/v2/pkg/apis/application"
)

type AppResourceTreeFn func(ctx context.Context, app *appv1.Application) (*appv1.ApplicationTree, error)

const (
	backgroundPropagationPolicy string = "background"
	foregroundPropagationPolicy string = "foreground"
)

var (
	watchAPIBufferSize  = env.ParseNumFromEnv(argocommon.EnvWatchAPIBufferSize, 1000, 0, math.MaxInt32)
	permissionDeniedErr = status.Error(codes.PermissionDenied, "permission denied")
)

// Server provides an Application service
type Server struct {
	ns                string
	kubeclientset     kubernetes.Interface
	appclientset      appclientset.Interface
	appLister         applisters.ApplicationLister
	appInformer       cache.SharedIndexInformer
	appBroadcaster    Broadcaster
	repoClientset     apiclient.Clientset
	kubectl           kube.Kubectl
	db                db.ArgoDB
	enf               *rbac.Enforcer
	projectLock       sync.KeyLock
	auditLogger       *argo.AuditLogger
	settingsMgr       *settings.SettingsManager
	cache             *servercache.Cache
	projInformer      cache.SharedIndexInformer
	enabledNamespaces []string
}

// NewServer returns a new instance of the Application service
func NewServer(
	namespace string,
	kubeclientset kubernetes.Interface,
	appclientset appclientset.Interface,
	appLister applisters.ApplicationLister,
	appInformer cache.SharedIndexInformer,
	appBroadcaster Broadcaster,
	repoClientset apiclient.Clientset,
	cache *servercache.Cache,
	kubectl kube.Kubectl,
	db db.ArgoDB,
	enf *rbac.Enforcer,
	projectLock sync.KeyLock,
	settingsMgr *settings.SettingsManager,
	projInformer cache.SharedIndexInformer,
	enabledNamespaces []string,
	enableK8sEvent []string,
) (application.ApplicationServiceServer, AppResourceTreeFn) {
	if appBroadcaster == nil {
		appBroadcaster = &broadcasterHandler{}
	}
	_, err := appInformer.AddEventHandler(appBroadcaster)
	if err != nil {
		log.Error(err)
	}
	s := &Server{
		ns:                namespace,
		appclientset:      appclientset,
		appLister:         appLister,
		appInformer:       appInformer,
		appBroadcaster:    appBroadcaster,
		kubeclientset:     kubeclientset,
		cache:             cache,
		db:                db,
		repoClientset:     repoClientset,
		kubectl:           kubectl,
		enf:               enf,
		projectLock:       projectLock,
		auditLogger:       argo.NewAuditLogger(namespace, kubeclientset, "argocd-server", enableK8sEvent),
		settingsMgr:       settingsMgr,
		projInformer:      projInformer,
		enabledNamespaces: enabledNamespaces,
	}
	return s, s.getAppResources
}

// getAppEnforceRBAC gets the Application with the given name in the given namespace. If no namespace is
// specified, the Application is fetched from the default namespace (the one in which the API server is running).
//
// If the user does not provide a "project," then we have to be very careful how we respond. If an app with the given
// name exists, and the user has access to that app in the app's project, we return the app. If the app exists but the
// user does not have access, we return "permission denied." If the app does not exist, we return "permission denied" -
// if we responded with a 404, then the user could infer that the app exists when they get "permission denied."
//
// If the user does provide a "project," we can respond more specifically. If the user does not have access to the given
// app name in the given project, we return "permission denied." If the app exists, but the project is different from
func (s *Server) getAppEnforceRBAC(ctx context.Context, action, project, namespace, name string, getApp func() (*appv1.Application, error)) (*appv1.Application, *appv1.AppProject, error) {
	user := session.Username(ctx)
	if user == "" {
		user = "Unknown user"
	}
	logCtx := log.WithFields(map[string]interface{}{
		"user":        user,
		"application": name,
		"namespace":   namespace,
	})
	if project != "" {
		// The user has provided everything we need to perform an initial RBAC check.
		givenRBACName := security.RBACName(s.ns, project, namespace, name)
		if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, action, givenRBACName); err != nil {
			logCtx.WithFields(map[string]interface{}{
				"project":                project,
				argocommon.SecurityField: argocommon.SecurityMedium,
			}).Warnf("user tried to %s application which they do not have access to: %s", action, err)
			// Do a GET on the app. This ensures that the timing of a "no access" response is the same as a "yes access,
			// but the app is in a different project" response. We don't want the user inferring the existence of the
			// app from response time.
			_, _ = getApp()
			return nil, nil, permissionDeniedErr
		}
	}
	a, err := getApp()
	if err != nil {
		if apierr.IsNotFound(err) {
			if project != "" {
				// We know that the user was allowed to get the Application, but the Application does not exist. Return 404.
				return nil, nil, status.Error(codes.NotFound, apierr.NewNotFound(schema.GroupResource{Group: "argoproj.io", Resource: "applications"}, name).Error())
			}
			// We don't know if the user was allowed to get the Application, and we don't want to leak information about
			// the Application's existence. Return 403.
			logCtx.Warn("application does not exist")
			return nil, nil, permissionDeniedErr
		}
		logCtx.Errorf("failed to get application: %s", err)
		return nil, nil, permissionDeniedErr
	}
	// Even if we performed an initial RBAC check (because the request was fully parameterized), we still need to
	// perform a second RBAC check to ensure that the user has access to the actual Application's project (not just the
	// project they specified in the request).
	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, action, a.RBACName(s.ns)); err != nil {
		logCtx.WithFields(map[string]interface{}{
			"project":                a.Spec.Project,
			argocommon.SecurityField: argocommon.SecurityMedium,
		}).Warnf("user tried to %s application which they do not have access to: %s", action, err)
		if project != "" {
			// The user specified a project. We would have returned a 404 if the user had access to the app, but the app
			// did not exist. So we have to return a 404 when the app does exist, but the user does not have access.
			// Otherwise, they could infer that the app exists based on the error code.
			return nil, nil, status.Error(codes.NotFound, apierr.NewNotFound(schema.GroupResource{Group: "argoproj.io", Resource: "applications"}, name).Error())
		}
		// The user didn't specify a project. We always return permission denied for both lack of access and lack of
		// existence.
		return nil, nil, permissionDeniedErr
	}
	effectiveProject := "default"
	if a.Spec.Project != "" {
		effectiveProject = a.Spec.Project
	}
	if project != "" && effectiveProject != project {
		logCtx.WithFields(map[string]interface{}{
			"project":                a.Spec.Project,
			argocommon.SecurityField: argocommon.SecurityMedium,
		}).Warnf("user tried to %s application in project %s, but the application is in project %s", action, project, effectiveProject)
		// The user has access to the app, but the app is in a different project. Return 404, meaning "app doesn't
		// exist in that project".
		return nil, nil, status.Error(codes.NotFound, apierr.NewNotFound(schema.GroupResource{Group: "argoproj.io", Resource: "applications"}, name).Error())
	}
	// Get the app's associated project, and make sure all project restrictions are enforced.
	proj, err := s.getAppProject(ctx, a, logCtx)
	if err != nil {
		return a, nil, err
	}
	return a, proj, nil
}

// getApplicationEnforceRBACInformer uses an informer to get an Application. If the app does not exist, permission is
// denied, or any other error occurs when getting the app, we return a permission denied error to obscure any sensitive
// information.
func (s *Server) getApplicationEnforceRBACInformer(ctx context.Context, action, project, namespace, name string) (*appv1.Application, *appv1.AppProject, error) {
	namespaceOrDefault := s.appNamespaceOrDefault(namespace)
	return s.getAppEnforceRBAC(ctx, action, project, namespaceOrDefault, name, func() (*appv1.Application, error) {
		return s.appLister.Applications(namespaceOrDefault).Get(name)
	})
}

// getApplicationEnforceRBACClient uses a client to get an Application. If the app does not exist, permission is denied,
// or any other error occurs when getting the app, we return a permission denied error to obscure any sensitive
// information.
func (s *Server) getApplicationEnforceRBACClient(ctx context.Context, action, project, namespace, name, resourceVersion string) (*appv1.Application, *appv1.AppProject, error) {
	namespaceOrDefault := s.appNamespaceOrDefault(namespace)
	return s.getAppEnforceRBAC(ctx, action, project, namespaceOrDefault, name, func() (*appv1.Application, error) {
		if !s.isNamespaceEnabled(namespaceOrDefault) {
			return nil, security.NamespaceNotPermittedError(namespaceOrDefault)
		}
		return s.appclientset.ArgoprojV1alpha1().Applications(namespaceOrDefault).Get(ctx, name, metav1.GetOptions{
			ResourceVersion: resourceVersion,
		})
	})
}

// List returns list of applications
func (s *Server) List(ctx context.Context, q *application.ApplicationQuery) (*appv1.ApplicationList, error) {
	selector, err := labels.Parse(q.GetSelector())
	if err != nil {
		return nil, fmt.Errorf("error parsing the selector: %w", err)
	}
	var apps []*appv1.Application
	if q.GetAppNamespace() == "" {
		apps, err = s.appLister.List(selector)
	} else {
		apps, err = s.appLister.Applications(q.GetAppNamespace()).List(selector)
	}
	if err != nil {
		return nil, fmt.Errorf("error listing apps with selectors: %w", err)
	}

	filteredApps := apps
	// Filter applications by name
	if q.Name != nil {
		filteredApps = argoutil.FilterByNameP(filteredApps, *q.Name)
	}

	// Filter applications by projects
	filteredApps = argoutil.FilterByProjectsP(filteredApps, getProjectsFromApplicationQuery(*q))

	// Filter applications by source repo URL
	filteredApps = argoutil.FilterByRepoP(filteredApps, q.GetRepo())

	newItems := make([]appv1.Application, 0)
	for _, a := range filteredApps {
		// Skip any application that is neither in the control plane's namespace
		// nor in the list of enabled namespaces.
		if !s.isNamespaceEnabled(a.Namespace) {
			continue
		}
		if s.enf.Enforce(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)) {
			newItems = append(newItems, *a)
		}
	}

	// Sort found applications by name
	sort.Slice(newItems, func(i, j int) bool {
		return newItems[i].Name < newItems[j].Name
	})

	appList := appv1.ApplicationList{
		ListMeta: metav1.ListMeta{
			ResourceVersion: s.appInformer.LastSyncResourceVersion(),
		},
		Items: newItems,
	}
	return &appList, nil
}

// Create creates an application
func (s *Server) Create(ctx context.Context, q *application.ApplicationCreateRequest) (*appv1.Application, error) {
	if q.GetApplication() == nil {
		return nil, fmt.Errorf("error creating application: application is nil in request")
	}
	a := q.GetApplication()

	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionCreate, a.RBACName(s.ns)); err != nil {
		return nil, err
	}

	s.projectLock.RLock(a.Spec.GetProject())
	defer s.projectLock.RUnlock(a.Spec.GetProject())

	validate := true
	if q.Validate != nil {
		validate = *q.Validate
	}

	proj, err := s.getAppProject(ctx, a, log.WithField("application", a.Name))
	if err != nil {
		return nil, err
	}

	err = s.validateAndNormalizeApp(ctx, a, proj, validate)
	if err != nil {
		return nil, fmt.Errorf("error while validating and normalizing app: %w", err)
	}

	appNs := s.appNamespaceOrDefault(a.Namespace)

	if !s.isNamespaceEnabled(appNs) {
		return nil, security.NamespaceNotPermittedError(appNs)
	}

	// Don't let the app creator set the operation explicitly. Those requests should always go through the Sync API.
	if a.Operation != nil {
		log.WithFields(log.Fields{
			"application":            a.Name,
			argocommon.SecurityField: argocommon.SecurityLow,
		}).Warn("User attempted to set operation on application creation. This could have allowed them to bypass branch protection rules by setting manifests directly. Ignoring the set operation.")
		a.Operation = nil
	}

	created, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Create(ctx, a, metav1.CreateOptions{})
	if err == nil {
		s.logAppEvent(created, ctx, argo.EventReasonResourceCreated, "created application")
		s.waitSync(created)
		return created, nil
	}
	if !apierr.IsAlreadyExists(err) {
		return nil, fmt.Errorf("error creating application: %w", err)
	}

	// act idempotent if existing spec matches new spec
	existing, err := s.appLister.Applications(appNs).Get(a.Name)
	if err != nil {
		return nil, status.Errorf(codes.Internal, "unable to check existing application details (%s): %v", appNs, err)
	}
	equalSpecs := reflect.DeepEqual(existing.Spec, a.Spec) &&
		reflect.DeepEqual(existing.Labels, a.Labels) &&
		reflect.DeepEqual(existing.Annotations, a.Annotations) &&
		reflect.DeepEqual(existing.Finalizers, a.Finalizers)

	if equalSpecs {
		return existing, nil
	}
	if q.Upsert == nil || !*q.Upsert {
		return nil, status.Errorf(codes.InvalidArgument, "existing application spec is different, use upsert flag to force update")
	}
	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, a.RBACName(s.ns)); err != nil {
		return nil, err
	}
	updated, err := s.updateApp(existing, a, ctx, true)
	if err != nil {
		return nil, fmt.Errorf("error updating application: %w", err)
	}
	return updated, nil
}

func (s *Server) queryRepoServer(ctx context.Context, proj *appv1.AppProject, action func(
	client apiclient.RepoServerServiceClient,
	helmRepos []*appv1.Repository,
	helmCreds []*appv1.RepoCreds,
	helmOptions *appv1.HelmOptions,
	enabledSourceTypes map[string]bool,
) error,
) error {
	closer, client, err := s.repoClientset.NewRepoServerClient()
	if err != nil {
		return fmt.Errorf("error creating repo server client: %w", err)
	}
	defer ioutil.Close(closer)

	helmRepos, err := s.db.ListHelmRepositories(ctx)
	if err != nil {
		return fmt.Errorf("error listing helm repositories: %w", err)
	}

	permittedHelmRepos, err := argo.GetPermittedRepos(proj, helmRepos)
	if err != nil {
		return fmt.Errorf("error retrieving permitted repos: %w", err)
	}
	helmRepositoryCredentials, err := s.db.GetAllHelmRepositoryCredentials(ctx)
	if err != nil {
		return fmt.Errorf("error getting helm repository credentials: %w", err)
	}
	helmOptions, err := s.settingsMgr.GetHelmSettings()
	if err != nil {
		return fmt.Errorf("error getting helm settings: %w", err)
	}
	permittedHelmCredentials, err := argo.GetPermittedReposCredentials(proj, helmRepositoryCredentials)
	if err != nil {
		return fmt.Errorf("error getting permitted repos credentials: %w", err)
	}
	enabledSourceTypes, err := s.settingsMgr.GetEnabledSourceTypes()
	if err != nil {
		return fmt.Errorf("error getting settings enabled source types: %w", err)
	}
	return action(client, permittedHelmRepos, permittedHelmCredentials, helmOptions, enabledSourceTypes)
}

// GetManifests returns application manifests
func (s *Server) GetManifests(ctx context.Context, q *application.ApplicationManifestQuery) (*apiclient.ManifestResponse, error) {
	if q.Name == nil || *q.Name == "" {
		return nil, fmt.Errorf("invalid request: application name is missing")
	}
	a, proj, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil {
		return nil, err
	}

	if !s.isNamespaceEnabled(a.Namespace) {
		return nil, security.NamespaceNotPermittedError(a.Namespace)
	}

	manifestInfos := make([]*apiclient.ManifestResponse, 0)
	err = s.queryRepoServer(ctx, proj, func(
		client apiclient.RepoServerServiceClient, helmRepos []*appv1.Repository, helmCreds []*appv1.RepoCreds, helmOptions *appv1.HelmOptions, enableGenerateManifests map[string]bool,
	) error {
		appInstanceLabelKey, err := s.settingsMgr.GetAppInstanceLabelKey()
		if err != nil {
			return fmt.Errorf("error getting app instance label key from settings: %w", err)
		}

		config, err := s.getApplicationClusterConfig(ctx, a)
		if err != nil {
			return fmt.Errorf("error getting application cluster config: %w", err)
		}

		serverVersion, err := s.kubectl.GetServerVersion(config)
		if err != nil {
			return fmt.Errorf("error getting server version: %w", err)
		}

		apiResources, err := s.kubectl.GetAPIResources(config, false, kubecache.NewNoopSettings())
		if err != nil {
			return fmt.Errorf("error getting API resources: %w", err)
		}

		sources := make([]appv1.ApplicationSource, 0)
		appSpec := a.Spec.DeepCopy()
		if a.Spec.HasMultipleSources() {
			numOfSources := int64(len(a.Spec.GetSources()))
			for i, pos := range q.SourcePositions {
				if pos <= 0 || pos > numOfSources {
					return fmt.Errorf("source position is out of range")
				}
				appSpec.Sources[pos-1].TargetRevision = q.Revisions[i]
			}
			sources = appSpec.GetSources()
		} else {
			source := a.Spec.GetSource()
			if q.GetRevision() != "" {
				source.TargetRevision = q.GetRevision()
			}
			sources = append(sources, source)
		}

		// Store the map of all sources having ref field into a map for applications with sources field
		refSources, err := argo.GetRefSources(context.Background(), sources, appSpec.Project, s.db.GetRepository, []string{}, false)
		if err != nil {
			return fmt.Errorf("failed to get ref sources: %w", err)
		}

		for _, source := range sources {
			repo, err := s.db.GetRepository(ctx, source.RepoURL, proj.Name)
			if err != nil {
				return fmt.Errorf("error getting repository: %w", err)
			}

			kustomizeSettings, err := s.settingsMgr.GetKustomizeSettings()
			if err != nil {
				return fmt.Errorf("error getting kustomize settings: %w", err)
			}

			kustomizeOptions, err := kustomizeSettings.GetOptions(source)
			if err != nil {
				return fmt.Errorf("error getting kustomize settings options: %w", err)
			}
			installationID, err := s.settingsMgr.GetInstallationID()
			if err != nil {
				return fmt.Errorf("error getting installation ID: %w", err)
			}

			manifestInfo, err := client.GenerateManifest(ctx, &apiclient.ManifestRequest{
				Repo:               repo,
				Revision:           source.TargetRevision,
				AppLabelKey:        appInstanceLabelKey,
				AppName:            a.InstanceName(s.ns),
				Namespace:          a.Spec.Destination.Namespace,
				ApplicationSource:  &source,
				Repos:              helmRepos,
				KustomizeOptions:   kustomizeOptions,
				KubeVersion:        serverVersion,
				ApiVersions:        argo.APIResourcesToStrings(apiResources, true),
				HelmRepoCreds:      helmCreds,
				HelmOptions:        helmOptions,
				TrackingMethod:     string(argoutil.GetTrackingMethod(s.settingsMgr)),
				EnabledSourceTypes: enableGenerateManifests,
				ProjectName:        proj.Name,
				ProjectSourceRepos: proj.Spec.SourceRepos,
				HasMultipleSources: a.Spec.HasMultipleSources(),
				RefSources:         refSources,
				InstallationID:     installationID,
			})
			if err != nil {
				return fmt.Errorf("error generating manifests: %w", err)
			}
			manifestInfos = append(manifestInfos, manifestInfo)
		}
		return nil
	})
	if err != nil {
		return nil, err
	}

	manifests := &apiclient.ManifestResponse{}
	for _, manifestInfo := range manifestInfos {
		for i, manifest := range manifestInfo.Manifests {
			obj := &unstructured.Unstructured{}
			err = json.Unmarshal([]byte(manifest), obj)
			if err != nil {
				return nil, fmt.Errorf("error unmarshaling manifest into unstructured: %w", err)
			}
			if obj.GetKind() == kube.SecretKind && obj.GroupVersionKind().Group == "" {
				obj, _, err = diff.HideSecretData(obj, nil)
				if err != nil {
					return nil, fmt.Errorf("error hiding secret data: %w", err)
				}
				data, err := json.Marshal(obj)
				if err != nil {
					return nil, fmt.Errorf("error marshaling manifest: %w", err)
				}
				manifestInfo.Manifests[i] = string(data)
			}
		}
		manifests.Manifests = append(manifests.Manifests, manifestInfo.Manifests...)
	}

	return manifests, nil
}

func (s *Server) GetManifestsWithFiles(stream application.ApplicationService_GetManifestsWithFilesServer) error {
	ctx := stream.Context()
	query, err := manifeststream.ReceiveApplicationManifestQueryWithFiles(stream)
	if err != nil {
		return fmt.Errorf("error getting query: %w", err)
	}

	if query.Name == nil || *query.Name == "" {
		return fmt.Errorf("invalid request: application name is missing")
	}

	a, proj, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, query.GetProject(), query.GetAppNamespace(), query.GetName())
	if err != nil {
		return err
	}

	var manifestInfo *apiclient.ManifestResponse
	err = s.queryRepoServer(ctx, proj, func(
		client apiclient.RepoServerServiceClient, helmRepos []*appv1.Repository, helmCreds []*appv1.RepoCreds, helmOptions *appv1.HelmOptions, enableGenerateManifests map[string]bool,
	) error {
		appInstanceLabelKey, err := s.settingsMgr.GetAppInstanceLabelKey()
		if err != nil {
			return fmt.Errorf("error getting app instance label key from settings: %w", err)
		}

		config, err := s.getApplicationClusterConfig(ctx, a)
		if err != nil {
			return fmt.Errorf("error getting application cluster config: %w", err)
		}

		serverVersion, err := s.kubectl.GetServerVersion(config)
		if err != nil {
			return fmt.Errorf("error getting server version: %w", err)
		}

		apiResources, err := s.kubectl.GetAPIResources(config, false, kubecache.NewNoopSettings())
		if err != nil {
			return fmt.Errorf("error getting API resources: %w", err)
		}

		source := a.Spec.GetSource()

		proj, err := argo.GetAppProject(a, applisters.NewAppProjectLister(s.projInformer.GetIndexer()), s.ns, s.settingsMgr, s.db, ctx)
		if err != nil {
			return fmt.Errorf("error getting app project: %w", err)
		}

		repo, err := s.db.GetRepository(ctx, a.Spec.GetSource().RepoURL, proj.Name)
		if err != nil {
			return fmt.Errorf("error getting repository: %w", err)
		}

		kustomizeSettings, err := s.settingsMgr.GetKustomizeSettings()
		if err != nil {
			return fmt.Errorf("error getting kustomize settings: %w", err)
		}
		kustomizeOptions, err := kustomizeSettings.GetOptions(a.Spec.GetSource())
		if err != nil {
			return fmt.Errorf("error getting kustomize settings options: %w", err)
		}

		req := &apiclient.ManifestRequest{
			Repo:               repo,
			Revision:           source.TargetRevision,
			AppLabelKey:        appInstanceLabelKey,
			AppName:            a.Name,
			Namespace:          a.Spec.Destination.Namespace,
			ApplicationSource:  &source,
			Repos:              helmRepos,
			KustomizeOptions:   kustomizeOptions,
			KubeVersion:        serverVersion,
			ApiVersions:        argo.APIResourcesToStrings(apiResources, true),
			HelmRepoCreds:      helmCreds,
			HelmOptions:        helmOptions,
			TrackingMethod:     string(argoutil.GetTrackingMethod(s.settingsMgr)),
			EnabledSourceTypes: enableGenerateManifests,
			ProjectName:        proj.Name,
			ProjectSourceRepos: proj.Spec.SourceRepos,
		}

		repoStreamClient, err := client.GenerateManifestWithFiles(stream.Context())
		if err != nil {
			return fmt.Errorf("error opening stream: %w", err)
		}

		err = manifeststream.SendRepoStream(repoStreamClient, stream, req, *query.Checksum)
		if err != nil {
			return fmt.Errorf("error sending repo stream: %w", err)
		}

		resp, err := repoStreamClient.CloseAndRecv()
		if err != nil {
			return fmt.Errorf("error generating manifests: %w", err)
		}

		manifestInfo = resp
		return nil
	})
	if err != nil {
		return err
	}

	for i, manifest := range manifestInfo.Manifests {
		obj := &unstructured.Unstructured{}
		err = json.Unmarshal([]byte(manifest), obj)
		if err != nil {
			return fmt.Errorf("error unmarshaling manifest into unstructured: %w", err)
		}
		if obj.GetKind() == kube.SecretKind && obj.GroupVersionKind().Group == "" {
			obj, _, err = diff.HideSecretData(obj, nil)
			if err != nil {
				return fmt.Errorf("error hiding secret data: %w", err)
			}
			data, err := json.Marshal(obj)
			if err != nil {
				return fmt.Errorf("error marshaling manifest: %w", err)
			}
			manifestInfo.Manifests[i] = string(data)
		}
	}

	stream.SendAndClose(manifestInfo)
	return nil
}

// Get returns an application by name
func (s *Server) Get(ctx context.Context, q *application.ApplicationQuery) (*appv1.Application, error) {
	appName := q.GetName()
	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())

	project := ""
	projects := getProjectsFromApplicationQuery(*q)
	if len(projects) == 1 {
		project = projects[0]
	} else if len(projects) > 1 {
		return nil, status.Errorf(codes.InvalidArgument, "multiple projects specified - the get endpoint accepts either zero or one project")
	}

	// We must use a client Get instead of an informer Get, because it's common to call Get immediately
	// following a Watch (which is not yet powered by an informer), and the Get must reflect what was
	// previously seen by the client.
	a, proj, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, project, appNs, appName, q.GetResourceVersion())
	if err != nil {
		return nil, err
	}

	s.inferResourcesStatusHealth(a)

	if q.Refresh == nil {
		return a, nil
	}

	refreshType := appv1.RefreshTypeNormal
	if *q.Refresh == string(appv1.RefreshTypeHard) {
		refreshType = appv1.RefreshTypeHard
	}
	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)

	// subscribe early with buffered channel to ensure we don't miss events
	events := make(chan *appv1.ApplicationWatchEvent, watchAPIBufferSize)
	unsubscribe := s.appBroadcaster.Subscribe(events, func(event *appv1.ApplicationWatchEvent) bool {
		return event.Application.Name == appName && event.Application.Namespace == appNs
	})
	defer unsubscribe()

	app, err := argoutil.RefreshApp(appIf, appName, refreshType)
	if err != nil {
		return nil, fmt.Errorf("error refreshing the app: %w", err)
	}

	if refreshType == appv1.RefreshTypeHard {
		// force refresh cached application details
		if err := s.queryRepoServer(ctx, proj, func(
			client apiclient.RepoServerServiceClient,
			helmRepos []*appv1.Repository,
			_ []*appv1.RepoCreds,
			helmOptions *appv1.HelmOptions,
			enabledSourceTypes map[string]bool,
		) error {
			source := app.Spec.GetSource()
			repo, err := s.db.GetRepository(ctx, a.Spec.GetSource().RepoURL, proj.Name)
			if err != nil {
				return fmt.Errorf("error getting repository: %w", err)
			}
			kustomizeSettings, err := s.settingsMgr.GetKustomizeSettings()
			if err != nil {
				return fmt.Errorf("error getting kustomize settings: %w", err)
			}
			kustomizeOptions, err := kustomizeSettings.GetOptions(a.Spec.GetSource())
			if err != nil {
				return fmt.Errorf("error getting kustomize settings options: %w", err)
			}
			_, err = client.GetAppDetails(ctx, &apiclient.RepoServerAppDetailsQuery{
				Repo:               repo,
				Source:             &source,
				AppName:            appName,
				KustomizeOptions:   kustomizeOptions,
				Repos:              helmRepos,
				NoCache:            true,
				TrackingMethod:     string(argoutil.GetTrackingMethod(s.settingsMgr)),
				EnabledSourceTypes: enabledSourceTypes,
				HelmOptions:        helmOptions,
			})
			return err
		}); err != nil {
			log.Warnf("Failed to force refresh application details: %v", err)
		}
	}

	minVersion := 0
	if minVersion, err = strconv.Atoi(app.ResourceVersion); err != nil {
		minVersion = 0
	}

	for {
		select {
		case <-ctx.Done():
			return nil, fmt.Errorf("application refresh deadline exceeded")
		case event := <-events:
			if appVersion, err := strconv.Atoi(event.Application.ResourceVersion); err == nil && appVersion > minVersion {
				annotations := event.Application.GetAnnotations()
				if annotations == nil {
					annotations = make(map[string]string)
				}
				if _, ok := annotations[appv1.AnnotationKeyRefresh]; !ok {
					return &event.Application, nil
				}
			}
		}
	}
}

// ListResourceEvents returns a list of event resources
func (s *Server) ListResourceEvents(ctx context.Context, q *application.ApplicationResourceEventsQuery) (*v1.EventList, error) {
	a, _, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil {
		return nil, err
	}

	var (
		kubeClientset kubernetes.Interface
		fieldSelector string
		namespace     string
	)
	// There are two places where we get events. If we are getting application events, we query
	// our own cluster. If it is events on a resource on an external cluster, then we query the
	// external cluster using its rest.Config
	if q.GetResourceName() == "" && q.GetResourceUID() == "" {
		kubeClientset = s.kubeclientset
		namespace = a.Namespace
		fieldSelector = fields.SelectorFromSet(map[string]string{
			"involvedObject.name":      a.Name,
			"involvedObject.uid":       string(a.UID),
			"involvedObject.namespace": a.Namespace,
		}).String()
	} else {
		tree, err := s.getAppResources(ctx, a)
		if err != nil {
			return nil, fmt.Errorf("error getting app resources: %w", err)
		}
		found := false
		for _, n := range append(tree.Nodes, tree.OrphanedNodes...) {
			if n.ResourceRef.UID == q.GetResourceUID() && n.ResourceRef.Name == q.GetResourceName() && n.ResourceRef.Namespace == q.GetResourceNamespace() {
				found = true
				break
			}
		}
		if !found {
			return nil, status.Errorf(codes.InvalidArgument, "%s not found as part of application %s", q.GetResourceName(), q.GetName())
		}

		namespace = q.GetResourceNamespace()
		var config *rest.Config
		config, err = s.getApplicationClusterConfig(ctx, a)
		if err != nil {
			return nil, fmt.Errorf("error getting application cluster config: %w", err)
		}
		kubeClientset, err = kubernetes.NewForConfig(config)
		if err != nil {
			return nil, fmt.Errorf("error creating kube client: %w", err)
		}
		fieldSelector = fields.SelectorFromSet(map[string]string{
			"involvedObject.name":      q.GetResourceName(),
			"involvedObject.uid":       q.GetResourceUID(),
			"involvedObject.namespace": namespace,
		}).String()
	}
	log.Infof("Querying for resource events with field selector: %s", fieldSelector)
	opts := metav1.ListOptions{FieldSelector: fieldSelector}
	list, err := kubeClientset.CoreV1().Events(namespace).List(ctx, opts)
	if err != nil {
		return nil, fmt.Errorf("error listing resource events: %w", err)
	}
	return list, nil
}

// validateAndUpdateApp validates and updates the application. currentProject is the name of the project the app
// currently is under. If not specified, we assume that the app is under the project specified in the app spec.
func (s *Server) validateAndUpdateApp(ctx context.Context, newApp *appv1.Application, merge bool, validate bool, action string, currentProject string) (*appv1.Application, error) {
	s.projectLock.RLock(newApp.Spec.GetProject())
	defer s.projectLock.RUnlock(newApp.Spec.GetProject())

	app, proj, err := s.getApplicationEnforceRBACClient(ctx, action, currentProject, newApp.Namespace, newApp.Name, "")
	if err != nil {
		return nil, err
	}

	err = s.validateAndNormalizeApp(ctx, newApp, proj, validate)
	if err != nil {
		return nil, fmt.Errorf("error validating and normalizing app: %w", err)
	}

	a, err := s.updateApp(app, newApp, ctx, merge)
	if err != nil {
		return nil, fmt.Errorf("error updating application: %w", err)
	}
	return a, nil
}

var informerSyncTimeout = 2 * time.Second

// waitSync is a helper to wait until the application informer cache is synced after create/update.
// It waits until the app in the informer, has a resource version greater than the version in the
// supplied app, or after 2 seconds, whichever comes first. Returns true if synced.
// We use an informer cache for read operations (Get, List). Since the cache is only
// eventually consistent, it is possible that it doesn't reflect an application change immediately
// after a mutating API call (create/update). This function should be called after a creates &
// update to give a probable (but not guaranteed) chance of being up-to-date after the create/update.
func (s *Server) waitSync(app *appv1.Application) {
	logCtx := log.WithField("application", app.Name)
	deadline := time.Now().Add(informerSyncTimeout)
	minVersion, err := strconv.Atoi(app.ResourceVersion)
	if err != nil {
		logCtx.Warnf("waitSync failed: could not parse resource version %s", app.ResourceVersion)
		time.Sleep(50 * time.Millisecond) // sleep anyway
		return
	}
	for {
		if currApp, err := s.appLister.Applications(app.Namespace).Get(app.Name); err == nil {
			currVersion, err := strconv.Atoi(currApp.ResourceVersion)
			if err == nil && currVersion >= minVersion {
				return
			}
		}
		if time.Now().After(deadline) {
			break
		}
		time.Sleep(20 * time.Millisecond)
	}
	logCtx.Warnf("waitSync failed: timed out")
}

func (s *Server) updateApp(app *appv1.Application, newApp *appv1.Application, ctx context.Context, merge bool) (*appv1.Application, error) {
	for i := 0; i < 10; i++ {
		app.Spec = newApp.Spec
		if merge {
			app.Labels = collections.MergeStringMaps(app.Labels, newApp.Labels)
			app.Annotations = collections.MergeStringMaps(app.Annotations, newApp.Annotations)
		} else {
			app.Labels = newApp.Labels
			app.Annotations = newApp.Annotations
		}

		app.Finalizers = newApp.Finalizers

		res, err := s.appclientset.ArgoprojV1alpha1().Applications(app.Namespace).Update(ctx, app, metav1.UpdateOptions{})
		if err == nil {
			s.logAppEvent(app, ctx, argo.EventReasonResourceUpdated, "updated application spec")
			s.waitSync(res)
			return res, nil
		}
		if !apierr.IsConflict(err) {
			return nil, err
		}

		app, err = s.appclientset.ArgoprojV1alpha1().Applications(app.Namespace).Get(ctx, newApp.Name, metav1.GetOptions{})
		if err != nil {
			return nil, fmt.Errorf("error getting application: %w", err)
		}
		s.inferResourcesStatusHealth(app)
	}
	return nil, status.Errorf(codes.Internal, "Failed to update application. Too many conflicts")
}

// Update updates an application
func (s *Server) Update(ctx context.Context, q *application.ApplicationUpdateRequest) (*appv1.Application, error) {
	if q.GetApplication() == nil {
		return nil, fmt.Errorf("error updating application: application is nil in request")
	}
	a := q.GetApplication()
	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, a.RBACName(s.ns)); err != nil {
		return nil, err
	}

	validate := true
	if q.Validate != nil {
		validate = *q.Validate
	}
	return s.validateAndUpdateApp(ctx, q.Application, false, validate, rbacpolicy.ActionUpdate, q.GetProject())
}

// UpdateSpec updates an application spec and filters out any invalid parameter overrides
func (s *Server) UpdateSpec(ctx context.Context, q *application.ApplicationUpdateSpecRequest) (*appv1.ApplicationSpec, error) {
	if q.GetSpec() == nil {
		return nil, fmt.Errorf("error updating application spec: spec is nil in request")
	}
	a, _, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionUpdate, q.GetProject(), q.GetAppNamespace(), q.GetName(), "")
	if err != nil {
		return nil, err
	}

	a.Spec = *q.GetSpec()
	validate := true
	if q.Validate != nil {
		validate = *q.Validate
	}
	a, err = s.validateAndUpdateApp(ctx, a, false, validate, rbacpolicy.ActionUpdate, q.GetProject())
	if err != nil {
		return nil, fmt.Errorf("error validating and updating app: %w", err)
	}
	return &a.Spec, nil
}

// Patch patches an application
func (s *Server) Patch(ctx context.Context, q *application.ApplicationPatchRequest) (*appv1.Application, error) {
	app, _, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName(), "")
	if err != nil {
		return nil, err
	}

	if err = s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, app.RBACName(s.ns)); err != nil {
		return nil, err
	}

	jsonApp, err := json.Marshal(app)
	if err != nil {
		return nil, fmt.Errorf("error marshaling application: %w", err)
	}

	var patchApp []byte

	switch q.GetPatchType() {
	case "json", "":
		patch, err := jsonpatch.DecodePatch([]byte(q.GetPatch()))
		if err != nil {
			return nil, fmt.Errorf("error decoding json patch: %w", err)
		}
		patchApp, err = patch.Apply(jsonApp)
		if err != nil {
			return nil, fmt.Errorf("error applying patch: %w", err)
		}
	case "merge":
		patchApp, err = jsonpatch.MergePatch(jsonApp, []byte(q.GetPatch()))
		if err != nil {
			return nil, fmt.Errorf("error calculating merge patch: %w", err)
		}
	default:
		return nil, status.Error(codes.InvalidArgument, fmt.Sprintf("Patch type '%s' is not supported", q.GetPatchType()))
	}

	newApp := &appv1.Application{}
	err = json.Unmarshal(patchApp, newApp)
	if err != nil {
		return nil, fmt.Errorf("error unmarshaling patched app: %w", err)
	}
	return s.validateAndUpdateApp(ctx, newApp, false, true, rbacpolicy.ActionUpdate, q.GetProject())
}

func (s *Server) getAppProject(ctx context.Context, a *appv1.Application, logCtx *log.Entry) (*appv1.AppProject, error) {
	proj, err := argo.GetAppProject(a, applisters.NewAppProjectLister(s.projInformer.GetIndexer()), s.ns, s.settingsMgr, s.db, ctx)
	if err == nil {
		return proj, nil
	}

	// If there's a permission issue or the app doesn't exist, return a vague error to avoid letting the user enumerate project names.
	vagueError := status.Errorf(codes.InvalidArgument, "app is not allowed in project %q, or the project does not exist", a.Spec.Project)

	if apierr.IsNotFound(err) {
		return nil, vagueError
	}

	var applicationNotAllowedToUseProjectErr *appv1.ErrApplicationNotAllowedToUseProject
	if errors.As(err, &applicationNotAllowedToUseProjectErr) {
		logCtx.WithFields(map[string]interface{}{
			"project":                a.Spec.Project,
			argocommon.SecurityField: argocommon.SecurityMedium,
		}).Warnf("error getting app project: %s", err)
		return nil, vagueError
	}

	return nil, vagueError
}

// Delete removes an application and all associated resources
func (s *Server) Delete(ctx context.Context, q *application.ApplicationDeleteRequest) (*application.ApplicationResponse, error) {
	appName := q.GetName()
	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
	a, _, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, q.GetProject(), appNs, appName, "")
	if err != nil {
		return nil, err
	}

	s.projectLock.RLock(a.Spec.Project)
	defer s.projectLock.RUnlock(a.Spec.Project)

	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionDelete, a.RBACName(s.ns)); err != nil {
		return nil, err
	}

	if q.Cascade != nil && !*q.Cascade && q.GetPropagationPolicy() != "" {
		return nil, status.Error(codes.InvalidArgument, "cannot set propagation policy when cascading is disabled")
	}

	patchFinalizer := false
	if q.Cascade == nil || *q.Cascade {
		// validate the propgation policy
		policyFinalizer := getPropagationPolicyFinalizer(q.GetPropagationPolicy())
		if policyFinalizer == "" {
			return nil, status.Errorf(codes.InvalidArgument, "invalid propagation policy: %s", *q.PropagationPolicy)
		}
		if !a.IsFinalizerPresent(policyFinalizer) {
			a.SetCascadedDeletion(policyFinalizer)
			patchFinalizer = true
		}
	} else if a.CascadedDeletion() {
		a.UnSetCascadedDeletion()
		patchFinalizer = true
	}

	if patchFinalizer {
		// Although the cascaded deletion/propagation policy finalizer is not set when apps are created via
		// API, they will often be set by the user as part of declarative config. As part of a delete
		// request, we always calculate the patch to see if we need to set/unset the finalizer.
		patch, err := json.Marshal(map[string]interface{}{
			"metadata": map[string]interface{}{
				"finalizers": a.Finalizers,
			},
		})
		if err != nil {
			return nil, fmt.Errorf("error marshaling finalizers: %w", err)
		}
		_, err = s.appclientset.ArgoprojV1alpha1().Applications(a.Namespace).Patch(ctx, a.Name, types.MergePatchType, patch, metav1.PatchOptions{})
		if err != nil {
			return nil, fmt.Errorf("error patching application with finalizers: %w", err)
		}
	}

	err = s.appclientset.ArgoprojV1alpha1().Applications(appNs).Delete(ctx, appName, metav1.DeleteOptions{})
	if err != nil {
		return nil, fmt.Errorf("error deleting application: %w", err)
	}
	s.logAppEvent(a, ctx, argo.EventReasonResourceDeleted, "deleted application")
	return &application.ApplicationResponse{}, nil
}

func (s *Server) isApplicationPermitted(selector labels.Selector, minVersion int, claims any, appName, appNs string, projects map[string]bool, a appv1.Application) bool {
	if len(projects) > 0 && !projects[a.Spec.GetProject()] {
		return false
	}

	if appVersion, err := strconv.Atoi(a.ResourceVersion); err == nil && appVersion < minVersion {
		return false
	}
	matchedEvent := (appName == "" || (a.Name == appName && a.Namespace == appNs)) && selector.Matches(labels.Set(a.Labels))
	if !matchedEvent {
		return false
	}

	if !s.isNamespaceEnabled(a.Namespace) {
		return false
	}

	if !s.enf.Enforce(claims, rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)) {
		// do not emit apps user does not have accessing
		return false
	}

	return true
}

func (s *Server) Watch(q *application.ApplicationQuery, ws application.ApplicationService_WatchServer) error {
	appName := q.GetName()
	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
	logCtx := log.NewEntry(log.New())
	if q.Name != nil {
		logCtx = logCtx.WithField("application", *q.Name)
	}
	projects := map[string]bool{}
	for _, project := range getProjectsFromApplicationQuery(*q) {
		projects[project] = true
	}
	claims := ws.Context().Value("claims")
	selector, err := labels.Parse(q.GetSelector())
	if err != nil {
		return fmt.Errorf("error parsing labels with selectors: %w", err)
	}
	minVersion := 0
	if q.GetResourceVersion() != "" {
		if minVersion, err = strconv.Atoi(q.GetResourceVersion()); err != nil {
			minVersion = 0
		}
	}

	// sendIfPermitted is a helper to send the application to the client's streaming channel if the
	// caller has RBAC privileges permissions to view it
	sendIfPermitted := func(a appv1.Application, eventType watch.EventType) {
		permitted := s.isApplicationPermitted(selector, minVersion, claims, appName, appNs, projects, a)
		if !permitted {
			return
		}
		s.inferResourcesStatusHealth(&a)
		err := ws.Send(&appv1.ApplicationWatchEvent{
			Type:        eventType,
			Application: a,
		})
		if err != nil {
			logCtx.Warnf("Unable to send stream message: %v", err)
			return
		}
	}

	events := make(chan *appv1.ApplicationWatchEvent, watchAPIBufferSize)
	// Mimic watch API behavior: send ADDED events if no resource version provided
	// If watch API is executed for one application when emit event even if resource version is provided
	// This is required since single app watch API is used for during operations like app syncing and it is
	// critical to never miss events.
	if q.GetResourceVersion() == "" || q.GetName() != "" {
		apps, err := s.appLister.List(selector)
		if err != nil {
			return fmt.Errorf("error listing apps with selector: %w", err)
		}
		sort.Slice(apps, func(i, j int) bool {
			return apps[i].QualifiedName() < apps[j].QualifiedName()
		})
		for i := range apps {
			sendIfPermitted(*apps[i], watch.Added)
		}
	}
	unsubscribe := s.appBroadcaster.Subscribe(events)
	defer unsubscribe()
	for {
		select {
		case event := <-events:
			sendIfPermitted(event.Application, event.Type)
		case <-ws.Context().Done():
			return nil
		}
	}
}

func (s *Server) validateAndNormalizeApp(ctx context.Context, app *appv1.Application, proj *appv1.AppProject, validate bool) error {
	if app.GetName() == "" {
		return fmt.Errorf("resource name may not be empty")
	}
	appNs := s.appNamespaceOrDefault(app.Namespace)
	currApp, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, app.Name, metav1.GetOptions{})
	if err != nil {
		if !apierr.IsNotFound(err) {
			return fmt.Errorf("error getting application by name: %w", err)
		}
		// Kubernetes go-client will return a pointer to a zero-value app instead of nil, even
		// though the API response was NotFound. This behavior was confirmed via logs.
		currApp = nil
	}
	if currApp != nil && currApp.Spec.GetProject() != app.Spec.GetProject() {
		// When changing projects, caller must have application create & update privileges in new project
		// NOTE: the update check was already verified in the caller to this function
		if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionCreate, app.RBACName(s.ns)); err != nil {
			return err
		}
		// They also need 'update' privileges in the old project
		if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, currApp.RBACName(s.ns)); err != nil {
			return err
		}
	}

	if err := argo.ValidateDestination(ctx, &app.Spec.Destination, s.db); err != nil {
		return status.Errorf(codes.InvalidArgument, "application destination spec for %s is invalid: %s", app.Name, err.Error())
	}

	var conditions []appv1.ApplicationCondition

	if validate {
		conditions := make([]appv1.ApplicationCondition, 0)
		condition, err := argo.ValidateRepo(ctx, app, s.repoClientset, s.db, s.kubectl, proj, s.settingsMgr)
		if err != nil {
			return fmt.Errorf("error validating the repo: %w", err)
		}
		conditions = append(conditions, condition...)
		if len(conditions) > 0 {
			return status.Errorf(codes.InvalidArgument, "application spec for %s is invalid: %s", app.Name, argo.FormatAppConditions(conditions))
		}
	}

	conditions, err = argo.ValidatePermissions(ctx, &app.Spec, proj, s.db)
	if err != nil {
		return fmt.Errorf("error validating project permissions: %w", err)
	}
	if len(conditions) > 0 {
		return status.Errorf(codes.InvalidArgument, "application spec for %s is invalid: %s", app.Name, argo.FormatAppConditions(conditions))
	}

	app.Spec = *argo.NormalizeApplicationSpec(&app.Spec)
	return nil
}

func (s *Server) getApplicationClusterConfig(ctx context.Context, a *appv1.Application) (*rest.Config, error) {
	if err := argo.ValidateDestination(ctx, &a.Spec.Destination, s.db); err != nil {
		return nil, fmt.Errorf("error validating destination: %w", err)
	}
	clst, err := s.db.GetCluster(ctx, a.Spec.Destination.Server)
	if err != nil {
		return nil, fmt.Errorf("error getting cluster: %w", err)
	}
	config := clst.RESTConfig()
	return config, err
}

// getCachedAppState loads the cached state and trigger app refresh if cache is missing
func (s *Server) getCachedAppState(ctx context.Context, a *appv1.Application, getFromCache func() error) error {
	err := getFromCache()
	if err != nil && errors.Is(err, servercache.ErrCacheMiss) {
		conditions := a.Status.GetConditions(map[appv1.ApplicationConditionType]bool{
			appv1.ApplicationConditionComparisonError:  true,
			appv1.ApplicationConditionInvalidSpecError: true,
		})
		if len(conditions) > 0 {
			return errors.New(argoutil.FormatAppConditions(conditions))
		}
		_, err = s.Get(ctx, &application.ApplicationQuery{
			Name:         ptr.To(a.GetName()),
			AppNamespace: ptr.To(a.GetNamespace()),
			Refresh:      ptr.To(string(appv1.RefreshTypeNormal)),
		})
		if err != nil {
			return fmt.Errorf("error getting application by query: %w", err)
		}
		return getFromCache()
	}
	return err
}

func (s *Server) getAppResources(ctx context.Context, a *appv1.Application) (*appv1.ApplicationTree, error) {
	var tree appv1.ApplicationTree
	err := s.getCachedAppState(ctx, a, func() error {
		return s.cache.GetAppResourcesTree(a.InstanceName(s.ns), &tree)
	})
	if err != nil {
		return &tree, fmt.Errorf("error getting cached app resource tree: %w", err)
	}
	return &tree, nil
}

func (s *Server) getAppLiveResource(ctx context.Context, action string, q *application.ApplicationResourceRequest) (*appv1.ResourceNode, *rest.Config, *appv1.Application, error) {
	a, _, err := s.getApplicationEnforceRBACInformer(ctx, action, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil && errors.Is(err, permissionDeniedErr) && (action == rbacpolicy.ActionDelete || action == rbacpolicy.ActionUpdate) {
		// If users dont have permission on the whole applications, maybe they have fine-grained access to the specific resources
		action = fmt.Sprintf("%s/%s/%s/%s/%s", action, q.GetGroup(), q.GetKind(), q.GetNamespace(), q.GetResourceName())
		a, _, err = s.getApplicationEnforceRBACInformer(ctx, action, q.GetProject(), q.GetAppNamespace(), q.GetName())
	}
	if err != nil {
		return nil, nil, nil, err
	}

	tree, err := s.getAppResources(ctx, a)
	if err != nil {
		return nil, nil, nil, fmt.Errorf("error getting app resources: %w", err)
	}

	found := tree.FindNode(q.GetGroup(), q.GetKind(), q.GetNamespace(), q.GetResourceName())
	if found == nil || found.ResourceRef.UID == "" {
		return nil, nil, nil, status.Errorf(codes.InvalidArgument, "%s %s %s not found as part of application %s", q.GetKind(), q.GetGroup(), q.GetResourceName(), q.GetName())
	}
	config, err := s.getApplicationClusterConfig(ctx, a)
	if err != nil {
		return nil, nil, nil, fmt.Errorf("error getting application cluster config: %w", err)
	}
	return found, config, a, nil
}

func (s *Server) GetResource(ctx context.Context, q *application.ApplicationResourceRequest) (*application.ApplicationResourceResponse, error) {
	res, config, _, err := s.getAppLiveResource(ctx, rbacpolicy.ActionGet, q)
	if err != nil {
		return nil, err
	}

	// make sure to use specified resource version if provided
	if q.GetVersion() != "" {
		res.Version = q.GetVersion()
	}
	obj, err := s.kubectl.GetResource(ctx, config, res.GroupKindVersion(), res.Name, res.Namespace)
	if err != nil {
		return nil, fmt.Errorf("error getting resource: %w", err)
	}
	obj, err = replaceSecretValues(obj)
	if err != nil {
		return nil, fmt.Errorf("error replacing secret values: %w", err)
	}
	data, err := json.Marshal(obj.Object)
	if err != nil {
		return nil, fmt.Errorf("error marshaling object: %w", err)
	}
	manifest := string(data)
	return &application.ApplicationResourceResponse{Manifest: &manifest}, nil
}

func replaceSecretValues(obj *unstructured.Unstructured) (*unstructured.Unstructured, error) {
	if obj.GetKind() == kube.SecretKind && obj.GroupVersionKind().Group == "" {
		_, obj, err := diff.HideSecretData(nil, obj)
		if err != nil {
			return nil, err
		}
		return obj, err
	}
	return obj, nil
}

// PatchResource patches a resource
func (s *Server) PatchResource(ctx context.Context, q *application.ApplicationResourcePatchRequest) (*application.ApplicationResourceResponse, error) {
	resourceRequest := &application.ApplicationResourceRequest{
		Name:         q.Name,
		AppNamespace: q.AppNamespace,
		Namespace:    q.Namespace,
		ResourceName: q.ResourceName,
		Kind:         q.Kind,
		Version:      q.Version,
		Group:        q.Group,
		Project:      q.Project,
	}
	res, config, a, err := s.getAppLiveResource(ctx, rbacpolicy.ActionUpdate, resourceRequest)
	if err != nil {
		return nil, err
	}

	manifest, err := s.kubectl.PatchResource(ctx, config, res.GroupKindVersion(), res.Name, res.Namespace, types.PatchType(q.GetPatchType()), []byte(q.GetPatch()))
	if err != nil {
		// don't expose real error for secrets since it might contain secret data
		if res.Kind == kube.SecretKind && res.Group == "" {
			return nil, fmt.Errorf("failed to patch Secret %s/%s", res.Namespace, res.Name)
		}
		return nil, fmt.Errorf("error patching resource: %w", err)
	}
	if manifest == nil {
		return nil, fmt.Errorf("failed to patch resource: manifest was nil")
	}
	manifest, err = replaceSecretValues(manifest)
	if err != nil {
		return nil, fmt.Errorf("error replacing secret values: %w", err)
	}
	data, err := json.Marshal(manifest.Object)
	if err != nil {
		return nil, fmt.Errorf("erro marshaling manifest object: %w", err)
	}
	s.logAppEvent(a, ctx, argo.EventReasonResourceUpdated, fmt.Sprintf("patched resource %s/%s '%s'", q.GetGroup(), q.GetKind(), q.GetResourceName()))
	m := string(data)
	return &application.ApplicationResourceResponse{
		Manifest: &m,
	}, nil
}

// DeleteResource deletes a specified resource
func (s *Server) DeleteResource(ctx context.Context, q *application.ApplicationResourceDeleteRequest) (*application.ApplicationResponse, error) {
	resourceRequest := &application.ApplicationResourceRequest{
		Name:         q.Name,
		AppNamespace: q.AppNamespace,
		Namespace:    q.Namespace,
		ResourceName: q.ResourceName,
		Kind:         q.Kind,
		Version:      q.Version,
		Group:        q.Group,
		Project:      q.Project,
	}
	res, config, a, err := s.getAppLiveResource(ctx, rbacpolicy.ActionDelete, resourceRequest)
	if err != nil {
		return nil, err
	}
	var deleteOption metav1.DeleteOptions
	if q.GetOrphan() {
		propagationPolicy := metav1.DeletePropagationOrphan
		deleteOption = metav1.DeleteOptions{PropagationPolicy: &propagationPolicy}
	} else if q.GetForce() {
		propagationPolicy := metav1.DeletePropagationBackground
		zeroGracePeriod := int64(0)
		deleteOption = metav1.DeleteOptions{PropagationPolicy: &propagationPolicy, GracePeriodSeconds: &zeroGracePeriod}
	} else {
		propagationPolicy := metav1.DeletePropagationForeground
		deleteOption = metav1.DeleteOptions{PropagationPolicy: &propagationPolicy}
	}
	err = s.kubectl.DeleteResource(ctx, config, res.GroupKindVersion(), res.Name, res.Namespace, deleteOption)
	if err != nil {
		return nil, fmt.Errorf("error deleting resource: %w", err)
	}
	s.logAppEvent(a, ctx, argo.EventReasonResourceDeleted, fmt.Sprintf("deleted resource %s/%s '%s'", q.GetGroup(), q.GetKind(), q.GetResourceName()))
	return &application.ApplicationResponse{}, nil
}

func (s *Server) ResourceTree(ctx context.Context, q *application.ResourcesQuery) (*appv1.ApplicationTree, error) {
	a, _, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetApplicationName())
	if err != nil {
		return nil, err
	}

	return s.getAppResources(ctx, a)
}

func (s *Server) WatchResourceTree(q *application.ResourcesQuery, ws application.ApplicationService_WatchResourceTreeServer) error {
	_, _, err := s.getApplicationEnforceRBACInformer(ws.Context(), rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetApplicationName())
	if err != nil {
		return err
	}

	cacheKey := argo.AppInstanceName(q.GetApplicationName(), q.GetAppNamespace(), s.ns)
	return s.cache.OnAppResourcesTreeChanged(ws.Context(), cacheKey, func() error {
		var tree appv1.ApplicationTree
		err := s.cache.GetAppResourcesTree(cacheKey, &tree)
		if err != nil {
			return fmt.Errorf("error getting app resource tree: %w", err)
		}
		return ws.Send(&tree)
	})
}

func (s *Server) RevisionMetadata(ctx context.Context, q *application.RevisionMetadataQuery) (*appv1.RevisionMetadata, error) {
	a, proj, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil {
		return nil, err
	}

	source, err := getAppSourceBySourceIndexAndVersionId(a, q.SourceIndex, q.VersionId)
	if err != nil {
		return nil, fmt.Errorf("error getting app source by source index and version ID: %w", err)
	}

	repo, err := s.db.GetRepository(ctx, source.RepoURL, proj.Name)
	if err != nil {
		return nil, fmt.Errorf("error getting repository by URL: %w", err)
	}
	conn, repoClient, err := s.repoClientset.NewRepoServerClient()
	if err != nil {
		return nil, fmt.Errorf("error creating repo server client: %w", err)
	}
	defer ioutil.Close(conn)
	return repoClient.GetRevisionMetadata(ctx, &apiclient.RepoServerRevisionMetadataRequest{
		Repo:           repo,
		Revision:       q.GetRevision(),
		CheckSignature: len(proj.Spec.SignatureKeys) > 0,
	})
}

// RevisionChartDetails returns the helm chart metadata, as fetched from the reposerver
func (s *Server) RevisionChartDetails(ctx context.Context, q *application.RevisionMetadataQuery) (*appv1.ChartDetails, error) {
	a, _, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil {
		return nil, err
	}

	source, err := getAppSourceBySourceIndexAndVersionId(a, q.SourceIndex, q.VersionId)
	if err != nil {
		return nil, fmt.Errorf("error getting app source by source index and version ID: %w", err)
	}

	if source.Chart == "" {
		return nil, fmt.Errorf("no chart found for application: %v", q.GetName())
	}
	repo, err := s.db.GetRepository(ctx, source.RepoURL, a.Spec.Project)
	if err != nil {
		return nil, fmt.Errorf("error getting repository by URL: %w", err)
	}
	conn, repoClient, err := s.repoClientset.NewRepoServerClient()
	if err != nil {
		return nil, fmt.Errorf("error creating repo server client: %w", err)
	}
	defer ioutil.Close(conn)
	return repoClient.GetRevisionChartDetails(ctx, &apiclient.RepoServerRevisionChartDetailsRequest{
		Repo:     repo,
		Name:     source.Chart,
		Revision: q.GetRevision(),
	})
}

// getAppSourceBySourceIndexAndVersionId returns the source for a specific source index and version ID. Source index and
// version ID are optional. If the source index is not specified, it defaults to 0. If the version ID is not specified,
// we use the source(s) currently configured for the app. If the version ID is specified, we find the source for that
// version ID. If the version ID is not found, we return an error. If the source index is out of bounds for whichever
// source we choose (configured sources or sources for a specific version), we return an error.
func getAppSourceBySourceIndexAndVersionId(a *appv1.Application, sourceIndexMaybe *int32, versionIdMaybe *int32) (appv1.ApplicationSource, error) {
	// Start with all the app's configured sources.
	sources := a.Spec.GetSources()

	// If the user specified a version, get the sources for that version. If the version is not found, return an error.
	if versionIdMaybe != nil {
		versionId := int64(*versionIdMaybe)
		var err error
		sources, err = getSourcesByVersionId(a, versionId)
		if err != nil {
			return appv1.ApplicationSource{}, fmt.Errorf("error getting source by version ID: %w", err)
		}
	}

	// Start by assuming we want the first source.
	sourceIndex := 0

	// If the user specified a source index, use that instead.
	if sourceIndexMaybe != nil {
		sourceIndex = int(*sourceIndexMaybe)
		if sourceIndex >= len(sources) {
			if len(sources) == 1 {
				return appv1.ApplicationSource{}, fmt.Errorf("source index %d not found because there is only 1 source", sourceIndex)
			}
			return appv1.ApplicationSource{}, fmt.Errorf("source index %d not found because there are only %d sources", sourceIndex, len(sources))
		}
	}

	source := sources[sourceIndex]

	return source, nil
}

// getRevisionHistoryByVersionId returns the revision history for a specific version ID.
// If the version ID is not found, it returns an empty revision history and false.
func getRevisionHistoryByVersionId(histories v1alpha1.RevisionHistories, versionId int64) (appv1.RevisionHistory, bool) {
	for _, h := range histories {
		if h.ID == versionId {
			return h, true
		}
	}
	return appv1.RevisionHistory{}, false
}

// getSourcesByVersionId returns the sources for a specific version ID. If there is no history, it returns an error.
// If the version ID is not found, it returns an error. If the version ID is found, and there are multiple sources,
// it returns the sources for that version ID. If the version ID is found, and there is only one source, it returns
// a slice with just the single source.
func getSourcesByVersionId(a *appv1.Application, versionId int64) ([]appv1.ApplicationSource, error) {
	if len(a.Status.History) == 0 {
		return nil, fmt.Errorf("version ID %d not found because the app has no history", versionId)
	}

	h, ok := getRevisionHistoryByVersionId(a.Status.History, versionId)
	if !ok {
		return nil, fmt.Errorf("revision history not found for version ID %d", versionId)
	}

	if len(h.Sources) > 0 {
		return h.Sources, nil
	}

	return []v1alpha1.ApplicationSource{h.Source}, nil
}

func isMatchingResource(q *application.ResourcesQuery, key kube.ResourceKey) bool {
	return (q.GetName() == "" || q.GetName() == key.Name) &&
		(q.GetNamespace() == "" || q.GetNamespace() == key.Namespace) &&
		(q.GetGroup() == "" || q.GetGroup() == key.Group) &&
		(q.GetKind() == "" || q.GetKind() == key.Kind)
}

func (s *Server) ManagedResources(ctx context.Context, q *application.ResourcesQuery) (*application.ManagedResourcesResponse, error) {
	a, _, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetApplicationName())
	if err != nil {
		return nil, err
	}

	items := make([]*appv1.ResourceDiff, 0)
	err = s.getCachedAppState(ctx, a, func() error {
		return s.cache.GetAppManagedResources(a.InstanceName(s.ns), &items)
	})
	if err != nil {
		return nil, fmt.Errorf("error getting cached app managed resources: %w", err)
	}
	res := &application.ManagedResourcesResponse{}
	for i := range items {
		item := items[i]
		if !item.Hook && isMatchingResource(q, kube.ResourceKey{Name: item.Name, Namespace: item.Namespace, Kind: item.Kind, Group: item.Group}) {
			res.Items = append(res.Items, item)
		}
	}

	return res, nil
}

func (s *Server) PodLogs(q *application.ApplicationPodLogsQuery, ws application.ApplicationService_PodLogsServer) error {
	if q.PodName != nil {
		podKind := "Pod"
		q.Kind = &podKind
		q.ResourceName = q.PodName
	}

	var sinceSeconds, tailLines *int64
	if q.GetSinceSeconds() > 0 {
		sinceSeconds = ptr.To(q.GetSinceSeconds())
	}
	if q.GetTailLines() > 0 {
		tailLines = ptr.To(q.GetTailLines())
	}
	var untilTime *metav1.Time
	if q.GetUntilTime() != "" {
		if val, err := time.Parse(time.RFC3339Nano, q.GetUntilTime()); err != nil {
			return fmt.Errorf("invalid untilTime parameter value: %w", err)
		} else {
			untilTimeVal := metav1.NewTime(val)
			untilTime = &untilTimeVal
		}
	}

	literal := ""
	inverse := false
	if q.GetFilter() != "" {
		literal = *q.Filter
		if literal[0] == '!' {
			literal = literal[1:]
			inverse = true
		}
	}

	a, _, err := s.getApplicationEnforceRBACInformer(ws.Context(), rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName())
	if err != nil {
		return err
	}

	// Logs RBAC will be enforced only if an internal var serverRBACLogEnforceEnable (representing server.rbac.log.enforce.enable env var)
	// is defined and has a "true" value
	// Otherwise, no RBAC enforcement for logs will take place (meaning, PodLogs will return the logs,
	// even if there is no explicit RBAC allow, or if there is an explicit RBAC deny)
	serverRBACLogEnforceEnable, err := s.settingsMgr.GetServerRBACLogEnforceEnable()
	if err != nil {
		return fmt.Errorf("error getting RBAC log enforce enable: %w", err)
	}

	if serverRBACLogEnforceEnable {
		if err := s.enf.EnforceErr(ws.Context().Value("claims"), rbacpolicy.ResourceLogs, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
			return err
		}
	}

	tree, err := s.getAppResources(ws.Context(), a)
	if err != nil {
		return fmt.Errorf("error getting app resource tree: %w", err)
	}

	config, err := s.getApplicationClusterConfig(ws.Context(), a)
	if err != nil {
		return fmt.Errorf("error getting application cluster config: %w", err)
	}

	kubeClientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		return fmt.Errorf("error creating kube client: %w", err)
	}

	// from the tree find pods which match query of kind, group, and resource name
	pods := getSelectedPods(tree.Nodes, q)
	if len(pods) == 0 {
		return nil
	}

	maxPodLogsToRender, err := s.settingsMgr.GetMaxPodLogsToRender()
	if err != nil {
		return fmt.Errorf("error getting MaxPodLogsToRender config: %w", err)
	}

	if int64(len(pods)) > maxPodLogsToRender {
		return status.Error(codes.InvalidArgument, "max pods to view logs are reached. Please provide more granular query")
	}

	var streams []chan logEntry

	for _, pod := range pods {
		stream, err := kubeClientset.CoreV1().Pods(pod.Namespace).GetLogs(pod.Name, &v1.PodLogOptions{
			Container:    q.GetContainer(),
			Follow:       q.GetFollow(),
			Timestamps:   true,
			SinceSeconds: sinceSeconds,
			SinceTime:    q.GetSinceTime(),
			TailLines:    tailLines,
			Previous:     q.GetPrevious(),
		}).Stream(ws.Context())
		podName := pod.Name
		logStream := make(chan logEntry)
		if err == nil {
			defer ioutil.Close(stream)
		}

		streams = append(streams, logStream)
		go func() {
			// if k8s failed to start steaming logs (typically because Pod is not ready yet)
			// then the error should be shown in the UI so that user know the reason
			if err != nil {
				logStream <- logEntry{line: err.Error()}
			} else {
				parseLogsStream(podName, stream, logStream)
			}
			close(logStream)
		}()
	}

	logStream := mergeLogStreams(streams, time.Millisecond*100)
	sentCount := int64(0)
	done := make(chan error)
	go func() {
		for entry := range logStream {
			if entry.err != nil {
				done <- entry.err
				return
			} else {
				if q.Filter != nil {
					lineContainsFilter := strings.Contains(entry.line, literal)
					if (inverse && lineContainsFilter) || (!inverse && !lineContainsFilter) {
						continue
					}
				}
				ts := metav1.NewTime(entry.timeStamp)
				if untilTime != nil && entry.timeStamp.After(untilTime.Time) {
					done <- ws.Send(&application.LogEntry{
						Last:         ptr.To(true),
						PodName:      &entry.podName,
						Content:      &entry.line,
						TimeStampStr: ptr.To(entry.timeStamp.Format(time.RFC3339Nano)),
						TimeStamp:    &ts,
					})
					return
				} else {
					sentCount++
					if err := ws.Send(&application.LogEntry{
						PodName:      &entry.podName,
						Content:      &entry.line,
						TimeStampStr: ptr.To(entry.timeStamp.Format(time.RFC3339Nano)),
						TimeStamp:    &ts,
						Last:         ptr.To(false),
					}); err != nil {
						done <- err
						break
					}
				}
			}
		}
		now := time.Now()
		nowTS := metav1.NewTime(now)
		done <- ws.Send(&application.LogEntry{
			Last:         ptr.To(true),
			PodName:      ptr.To(""),
			Content:      ptr.To(""),
			TimeStampStr: ptr.To(now.Format(time.RFC3339Nano)),
			TimeStamp:    &nowTS,
		})
	}()

	select {
	case err := <-done:
		return err
	case <-ws.Context().Done():
		log.WithField("application", q.Name).Debug("k8s pod logs reader completed due to closed grpc context")
		return nil
	}
}

// from all of the treeNodes, get the pod who meets the criteria or whose parents meets the criteria
func getSelectedPods(treeNodes []appv1.ResourceNode, q *application.ApplicationPodLogsQuery) []appv1.ResourceNode {
	var pods []appv1.ResourceNode
	isTheOneMap := make(map[string]bool)
	for _, treeNode := range treeNodes {
		if treeNode.Kind == kube.PodKind && treeNode.Group == "" && treeNode.UID != "" {
			if isTheSelectedOne(&treeNode, q, treeNodes, isTheOneMap) {
				pods = append(pods, treeNode)
			}
		}
	}
	return pods
}

// check is currentNode is matching with group, kind, and name, or if any of its parents matches
func isTheSelectedOne(currentNode *appv1.ResourceNode, q *application.ApplicationPodLogsQuery, resourceNodes []appv1.ResourceNode, isTheOneMap map[string]bool) bool {
	exist, value := isTheOneMap[currentNode.UID]
	if exist {
		return value
	}

	if (q.GetResourceName() == "" || currentNode.Name == q.GetResourceName()) &&
		(q.GetKind() == "" || currentNode.Kind == q.GetKind()) &&
		(q.GetGroup() == "" || currentNode.Group == q.GetGroup()) &&
		(q.GetNamespace() == "" || currentNode.Namespace == q.GetNamespace()) {
		isTheOneMap[currentNode.UID] = true
		return true
	}

	if len(currentNode.ParentRefs) == 0 {
		isTheOneMap[currentNode.UID] = false
		return false
	}

	for _, parentResource := range currentNode.ParentRefs {
		// look up parentResource from resourceNodes
		// then check if the parent isTheSelectedOne
		for _, resourceNode := range resourceNodes {
			if resourceNode.Namespace == parentResource.Namespace &&
				resourceNode.Name == parentResource.Name &&
				resourceNode.Group == parentResource.Group &&
				resourceNode.Kind == parentResource.Kind {
				if isTheSelectedOne(&resourceNode, q, resourceNodes, isTheOneMap) {
					isTheOneMap[currentNode.UID] = true
					return true
				}
			}
		}
	}

	isTheOneMap[currentNode.UID] = false
	return false
}

// Sync syncs an application to its target state
func (s *Server) Sync(ctx context.Context, syncReq *application.ApplicationSyncRequest) (*appv1.Application, error) {
	a, proj, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, syncReq.GetProject(), syncReq.GetAppNamespace(), syncReq.GetName(), "")
	if err != nil {
		return nil, err
	}

	s.inferResourcesStatusHealth(a)

	canSync, err := proj.Spec.SyncWindows.Matches(a).CanSync(true)
	if err != nil {
		return a, status.Errorf(codes.PermissionDenied, "cannot sync: invalid sync window: %v", err)
	}
	if !canSync {
		return a, status.Errorf(codes.PermissionDenied, "cannot sync: blocked by sync window")
	}

	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionSync, a.RBACName(s.ns)); err != nil {
		return nil, err
	}

	if syncReq.Manifests != nil {
		if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionOverride, a.RBACName(s.ns)); err != nil {
			return nil, err
		}
		if a.Spec.SyncPolicy != nil && a.Spec.SyncPolicy.Automated != nil && !syncReq.GetDryRun() {
			return nil, status.Error(codes.FailedPrecondition, "cannot use local sync when Automatic Sync Policy is enabled unless for dry run")
		}
	}
	if a.DeletionTimestamp != nil {
		return nil, status.Errorf(codes.FailedPrecondition, "application is deleting")
	}

	revision, displayRevision, sourceRevisions, displayRevisions, err := s.resolveSourceRevisions(ctx, a, syncReq)
	if err != nil {
		return nil, err
	}

	var retry *appv1.RetryStrategy
	var syncOptions appv1.SyncOptions
	if a.Spec.SyncPolicy != nil {
		syncOptions = a.Spec.SyncPolicy.SyncOptions
		retry = a.Spec.SyncPolicy.Retry
	}
	if syncReq.RetryStrategy != nil {
		retry = syncReq.RetryStrategy
	}
	if syncReq.SyncOptions != nil {
		syncOptions = syncReq.SyncOptions.Items
	}

	// We cannot use local manifests if we're only allowed to sync to signed commits
	if syncReq.Manifests != nil && len(proj.Spec.SignatureKeys) > 0 {
		return nil, status.Errorf(codes.FailedPrecondition, "Cannot use local sync when signature keys are required.")
	}

	resources := []appv1.SyncOperationResource{}
	if syncReq.GetResources() != nil {
		for _, r := range syncReq.GetResources() {
			if r != nil {
				resources = append(resources, *r)
			}
		}
	}
	op := appv1.Operation{
		Sync: &appv1.SyncOperation{
			Revision:     revision,
			Prune:        syncReq.GetPrune(),
			DryRun:       syncReq.GetDryRun(),
			SyncOptions:  syncOptions,
			SyncStrategy: syncReq.Strategy,
			Resources:    resources,
			Manifests:    syncReq.Manifests,
			Sources:      a.Spec.Sources,
			Revisions:    sourceRevisions,
		},
		InitiatedBy: appv1.OperationInitiator{Username: session.Username(ctx)},
		Info:        syncReq.Infos,
	}
	if retry != nil {
		op.Retry = *retry
	}

	appName := syncReq.GetName()
	appNs := s.appNamespaceOrDefault(syncReq.GetAppNamespace())
	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
	a, err = argo.SetAppOperation(appIf, appName, &op)
	if err != nil {
		return nil, fmt.Errorf("error setting app operation: %w", err)
	}
	partial := ""
	if len(syncReq.Resources) > 0 {
		partial = "partial "
	}
	var reason string
	if a.Spec.HasMultipleSources() {
		reason = fmt.Sprintf("initiated %ssync to %s", partial, strings.Join(displayRevisions, ","))
	} else {
		reason = fmt.Sprintf("initiated %ssync to %s", partial, displayRevision)
	}
	if syncReq.Manifests != nil {
		reason = fmt.Sprintf("initiated %ssync locally", partial)
	}
	s.logAppEvent(a, ctx, argo.EventReasonOperationStarted, reason)
	return a, nil
}

func (s *Server) resolveSourceRevisions(ctx context.Context, a *appv1.Application, syncReq *application.ApplicationSyncRequest) (string, string, []string, []string, error) {
	if a.Spec.HasMultipleSources() {
		numOfSources := int64(len(a.Spec.GetSources()))
		sourceRevisions := make([]string, numOfSources)
		displayRevisions := make([]string, numOfSources)

		sources := a.Spec.GetSources()
		for i, pos := range syncReq.SourcePositions {
			if pos <= 0 || pos > numOfSources {
				return "", "", nil, nil, fmt.Errorf("source position is out of range")
			}
			sources[pos-1].TargetRevision = syncReq.Revisions[i]
		}
		for index, source := range sources {
			if a.Spec.SyncPolicy != nil && a.Spec.SyncPolicy.Automated != nil && !syncReq.GetDryRun() {
				if text.FirstNonEmpty(a.Spec.GetSources()[index].TargetRevision, "HEAD") != text.FirstNonEmpty(source.TargetRevision, "HEAD") {
					return "", "", nil, nil, status.Errorf(codes.FailedPrecondition, "Cannot sync source %s to %s: auto-sync currently set to %s", source.RepoURL, source.TargetRevision, a.Spec.Sources[index].TargetRevision)
				}
			}
			revision, displayRevision, err := s.resolveRevision(ctx, a, syncReq, index)
			if err != nil {
				return "", "", nil, nil, status.Error(codes.FailedPrecondition, err.Error())
			}
			sourceRevisions[index] = revision
			displayRevisions[index] = displayRevision
		}
		return "", "", sourceRevisions, displayRevisions, nil
	} else {
		source := a.Spec.GetSource()
		if a.Spec.SyncPolicy != nil && a.Spec.SyncPolicy.Automated != nil && !syncReq.GetDryRun() {
			if syncReq.GetRevision() != "" && syncReq.GetRevision() != text.FirstNonEmpty(source.TargetRevision, "HEAD") {
				return "", "", nil, nil, status.Errorf(codes.FailedPrecondition, "Cannot sync to %s: auto-sync currently set to %s", syncReq.GetRevision(), source.TargetRevision)
			}
		}
		revision, displayRevision, err := s.resolveRevision(ctx, a, syncReq, -1)
		if err != nil {
			return "", "", nil, nil, status.Error(codes.FailedPrecondition, err.Error())
		}
		return revision, displayRevision, nil, nil, nil
	}
}

func (s *Server) Rollback(ctx context.Context, rollbackReq *application.ApplicationRollbackRequest) (*appv1.Application, error) {
	a, _, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionSync, rollbackReq.GetProject(), rollbackReq.GetAppNamespace(), rollbackReq.GetName(), "")
	if err != nil {
		return nil, err
	}

	s.inferResourcesStatusHealth(a)

	if a.DeletionTimestamp != nil {
		return nil, status.Errorf(codes.FailedPrecondition, "application is deleting")
	}
	if a.Spec.SyncPolicy != nil && a.Spec.SyncPolicy.Automated != nil {
		return nil, status.Errorf(codes.FailedPrecondition, "rollback cannot be initiated when auto-sync is enabled")
	}

	var deploymentInfo *appv1.RevisionHistory
	for _, info := range a.Status.History {
		if info.ID == rollbackReq.GetId() {
			deploymentInfo = &info
			break
		}
	}
	if deploymentInfo == nil {
		return nil, status.Errorf(codes.InvalidArgument, "application %s does not have deployment with id %v", a.QualifiedName(), rollbackReq.GetId())
	}
	if deploymentInfo.Source.IsZero() && deploymentInfo.Sources.IsZero() {
		// Since source type was introduced to history starting with v0.12, and is now required for
		// rollback, we cannot support rollback to revisions deployed using Argo CD v0.11 or below
		// As multi source doesn't use app.Source, we need to check to the Sources length
		return nil, status.Errorf(codes.FailedPrecondition, "cannot rollback to revision deployed with Argo CD v0.11 or lower. sync to revision instead.")
	}

	var syncOptions appv1.SyncOptions
	if a.Spec.SyncPolicy != nil {
		syncOptions = a.Spec.SyncPolicy.SyncOptions
	}

	// Rollback is just a convenience around Sync
	op := appv1.Operation{
		Sync: &appv1.SyncOperation{
			Revision:     deploymentInfo.Revision,
			Revisions:    deploymentInfo.Revisions,
			DryRun:       rollbackReq.GetDryRun(),
			Prune:        rollbackReq.GetPrune(),
			SyncOptions:  syncOptions,
			SyncStrategy: &appv1.SyncStrategy{Apply: &appv1.SyncStrategyApply{}},
			Source:       &deploymentInfo.Source,
			Sources:      deploymentInfo.Sources,
		},
		InitiatedBy: appv1.OperationInitiator{Username: session.Username(ctx)},
	}
	appName := rollbackReq.GetName()
	appNs := s.appNamespaceOrDefault(rollbackReq.GetAppNamespace())
	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
	a, err = argo.SetAppOperation(appIf, appName, &op)
	if err != nil {
		return nil, fmt.Errorf("error setting app operation: %w", err)
	}
	s.logAppEvent(a, ctx, argo.EventReasonOperationStarted, fmt.Sprintf("initiated rollback to %d", rollbackReq.GetId()))
	return a, nil
}

func (s *Server) ListLinks(ctx context.Context, req *application.ListAppLinksRequest) (*application.LinksResponse, error) {
	a, proj, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, req.GetProject(), req.GetNamespace(), req.GetName(), "")
	if err != nil {
		return nil, err
	}

	obj, err := kube.ToUnstructured(a)
	if err != nil {
		return nil, fmt.Errorf("error getting application: %w", err)
	}

	deepLinks, err := s.settingsMgr.GetDeepLinks(settings.ApplicationDeepLinks)
	if err != nil {
		return nil, fmt.Errorf("failed to read application deep links from configmap: %w", err)
	}

	clstObj, _, err := s.getObjectsForDeepLinks(ctx, a, proj)
	if err != nil {
		return nil, err
	}

	deepLinksObject := deeplinks.CreateDeepLinksObject(nil, obj, clstObj, nil)

	finalList, errorList := deeplinks.EvaluateDeepLinksResponse(deepLinksObject, obj.GetName(), deepLinks)
	if len(errorList) > 0 {
		log.Errorf("errorList while evaluating application deep links, %v", strings.Join(errorList, ", "))
	}

	return finalList, nil
}

func (s *Server) getObjectsForDeepLinks(ctx context.Context, app *appv1.Application, proj *appv1.AppProject) (cluster *unstructured.Unstructured, project *unstructured.Unstructured, err error) {
	// sanitize project jwt tokens
	proj.Status = appv1.AppProjectStatus{}

	project, err = kube.ToUnstructured(proj)
	if err != nil {
		return nil, nil, err
	}

	getProjectClusters := func(project string) ([]*appv1.Cluster, error) {
		return s.db.GetProjectClusters(ctx, project)
	}

	if err := argo.ValidateDestination(ctx, &app.Spec.Destination, s.db); err != nil {
		log.WithFields(map[string]interface{}{
			"application": app.GetName(),
			"ns":          app.GetNamespace(),
			"destination": app.Spec.Destination,
		}).Warnf("cannot validate cluster, error=%v", err.Error())
		return nil, nil, nil
	}

	permitted, err := proj.IsDestinationPermitted(app.Spec.Destination, getProjectClusters)
	if err != nil {
		return nil, nil, err
	}
	if !permitted {
		return nil, nil, fmt.Errorf("error getting destination cluster")
	}
	clst, err := s.db.GetCluster(ctx, app.Spec.Destination.Server)
	if err != nil {
		log.WithFields(map[string]interface{}{
			"application": app.GetName(),
			"ns":          app.GetNamespace(),
			"destination": app.Spec.Destination,
		}).Warnf("cannot get cluster from db, error=%v", err.Error())
		return nil, nil, nil
	}
	// sanitize cluster, remove cluster config creds and other unwanted fields
	cluster, err = deeplinks.SanitizeCluster(clst)
	return cluster, project, err
}

func (s *Server) ListResourceLinks(ctx context.Context, req *application.ApplicationResourceRequest) (*application.LinksResponse, error) {
	obj, _, app, _, err := s.getUnstructuredLiveResourceOrApp(ctx, rbacpolicy.ActionGet, req)
	if err != nil {
		return nil, err
	}
	deepLinks, err := s.settingsMgr.GetDeepLinks(settings.ResourceDeepLinks)
	if err != nil {
		return nil, fmt.Errorf("failed to read application deep links from configmap: %w", err)
	}

	obj, err = replaceSecretValues(obj)
	if err != nil {
		return nil, fmt.Errorf("error replacing secret values: %w", err)
	}

	appObj, err := kube.ToUnstructured(app)
	if err != nil {
		return nil, err
	}

	proj, err := s.getAppProject(ctx, app, log.WithField("application", app.GetName()))
	if err != nil {
		return nil, err
	}

	clstObj, projObj, err := s.getObjectsForDeepLinks(ctx, app, proj)
	if err != nil {
		return nil, err
	}

	deepLinksObject := deeplinks.CreateDeepLinksObject(obj, appObj, clstObj, projObj)
	finalList, errorList := deeplinks.EvaluateDeepLinksResponse(deepLinksObject, obj.GetName(), deepLinks)
	if len(errorList) > 0 {
		log.Errorf("errors while evaluating resource deep links, %v", strings.Join(errorList, ", "))
	}

	return finalList, nil
}

func getAmbiguousRevision(app *appv1.Application, syncReq *application.ApplicationSyncRequest, sourceIndex int) string {
	ambiguousRevision := ""
	if app.Spec.HasMultipleSources() {
		for i, pos := range syncReq.SourcePositions {
			if pos == int64(sourceIndex+1) {
				ambiguousRevision = syncReq.Revisions[i]
			}
		}
		if ambiguousRevision == "" {
			ambiguousRevision = app.Spec.Sources[sourceIndex].TargetRevision
		}
	} else {
		ambiguousRevision = syncReq.GetRevision()
		if ambiguousRevision == "" {
			ambiguousRevision = app.Spec.GetSource().TargetRevision
		}
	}
	return ambiguousRevision
}

// resolveRevision resolves the revision specified either in the sync request, or the
// application source, into a concrete revision that will be used for a sync operation.
func (s *Server) resolveRevision(ctx context.Context, app *appv1.Application, syncReq *application.ApplicationSyncRequest, sourceIndex int) (string, string, error) {
	if syncReq.Manifests != nil {
		return "", "", nil
	}

	ambiguousRevision := getAmbiguousRevision(app, syncReq, sourceIndex)

	repoUrl := app.Spec.GetSource().RepoURL
	if app.Spec.HasMultipleSources() {
		repoUrl = app.Spec.Sources[sourceIndex].RepoURL
	}

	repo, err := s.db.GetRepository(ctx, repoUrl, app.Spec.Project)
	if err != nil {
		return "", "", fmt.Errorf("error getting repository by URL: %w", err)
	}
	conn, repoClient, err := s.repoClientset.NewRepoServerClient()
	if err != nil {
		return "", "", fmt.Errorf("error getting repo server client: %w", err)
	}
	defer ioutil.Close(conn)

	source := app.Spec.GetSourcePtrByIndex(sourceIndex)
	if !source.IsHelm() {
		if git.IsCommitSHA(ambiguousRevision) {
			// If it's already a commit SHA, then no need to look it up
			return ambiguousRevision, ambiguousRevision, nil
		}
	}

	resolveRevisionResponse, err := repoClient.ResolveRevision(ctx, &apiclient.ResolveRevisionRequest{
		Repo:              repo,
		App:               app,
		AmbiguousRevision: ambiguousRevision,
		SourceIndex:       int64(sourceIndex),
	})
	if err != nil {
		return "", "", fmt.Errorf("error resolving repo revision: %w", err)
	}
	return resolveRevisionResponse.Revision, resolveRevisionResponse.AmbiguousRevision, nil
}

func (s *Server) TerminateOperation(ctx context.Context, termOpReq *application.OperationTerminateRequest) (*application.OperationTerminateResponse, error) {
	appName := termOpReq.GetName()
	appNs := s.appNamespaceOrDefault(termOpReq.GetAppNamespace())
	a, _, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionSync, termOpReq.GetProject(), appNs, appName, "")
	if err != nil {
		return nil, err
	}

	for i := 0; i < 10; i++ {
		if a.Operation == nil || a.Status.OperationState == nil {
			return nil, status.Errorf(codes.InvalidArgument, "Unable to terminate operation. No operation is in progress")
		}
		a.Status.OperationState.Phase = common.OperationTerminating
		updated, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Update(ctx, a, metav1.UpdateOptions{})
		if err == nil {
			s.waitSync(updated)
			s.logAppEvent(a, ctx, argo.EventReasonResourceUpdated, "terminated running operation")
			return &application.OperationTerminateResponse{}, nil
		}
		if !apierr.IsConflict(err) {
			return nil, fmt.Errorf("error updating application: %w", err)
		}
		log.Warnf("failed to set operation for app %q due to update conflict. retrying again...", *termOpReq.Name)
		time.Sleep(100 * time.Millisecond)
		a, err = s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
		if err != nil {
			return nil, fmt.Errorf("error getting application by name: %w", err)
		}
	}
	return nil, status.Errorf(codes.Internal, "Failed to terminate app. Too many conflicts")
}

func (s *Server) logAppEvent(a *appv1.Application, ctx context.Context, reason string, action string) {
	eventInfo := argo.EventInfo{Type: v1.EventTypeNormal, Reason: reason}
	user := session.Username(ctx)
	if user == "" {
		user = "Unknown user"
	}
	message := fmt.Sprintf("%s %s", user, action)
	eventLabels := argo.GetAppEventLabels(a, applisters.NewAppProjectLister(s.projInformer.GetIndexer()), s.ns, s.settingsMgr, s.db, ctx)
	s.auditLogger.LogAppEvent(a, eventInfo, message, user, eventLabels)
}

func (s *Server) logResourceEvent(res *appv1.ResourceNode, ctx context.Context, reason string, action string) {
	eventInfo := argo.EventInfo{Type: v1.EventTypeNormal, Reason: reason}
	user := session.Username(ctx)
	if user == "" {
		user = "Unknown user"
	}
	message := fmt.Sprintf("%s %s", user, action)
	s.auditLogger.LogResourceEvent(res, eventInfo, message, user)
}

func (s *Server) ListResourceActions(ctx context.Context, q *application.ApplicationResourceRequest) (*application.ResourceActionsListResponse, error) {
	obj, _, _, _, err := s.getUnstructuredLiveResourceOrApp(ctx, rbacpolicy.ActionGet, q)
	if err != nil {
		return nil, err
	}
	resourceOverrides, err := s.settingsMgr.GetResourceOverrides()
	if err != nil {
		return nil, fmt.Errorf("error getting resource overrides: %w", err)
	}

	availableActions, err := s.getAvailableActions(resourceOverrides, obj)
	if err != nil {
		return nil, fmt.Errorf("error getting available actions: %w", err)
	}
	actionsPtr := []*appv1.ResourceAction{}
	for i := range availableActions {
		actionsPtr = append(actionsPtr, &availableActions[i])
	}

	return &application.ResourceActionsListResponse{Actions: actionsPtr}, nil
}

func (s *Server) getUnstructuredLiveResourceOrApp(ctx context.Context, rbacRequest string, q *application.ApplicationResourceRequest) (obj *unstructured.Unstructured, res *appv1.ResourceNode, app *appv1.Application, config *rest.Config, err error) {
	if q.GetKind() == applicationType.ApplicationKind && q.GetGroup() == applicationType.Group && q.GetName() == q.GetResourceName() {
		app, _, err = s.getApplicationEnforceRBACInformer(ctx, rbacRequest, q.GetProject(), q.GetAppNamespace(), q.GetName())
		if err != nil {
			return nil, nil, nil, nil, err
		}
		if err = s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacRequest, app.RBACName(s.ns)); err != nil {
			return nil, nil, nil, nil, err
		}
		config, err = s.getApplicationClusterConfig(ctx, app)
		if err != nil {
			return nil, nil, nil, nil, fmt.Errorf("error getting application cluster config: %w", err)
		}
		obj, err = kube.ToUnstructured(app)
	} else {
		res, config, app, err = s.getAppLiveResource(ctx, rbacRequest, q)
		if err != nil {
			return nil, nil, nil, nil, err
		}
		obj, err = s.kubectl.GetResource(ctx, config, res.GroupKindVersion(), res.Name, res.Namespace)
	}
	if err != nil {
		return nil, nil, nil, nil, fmt.Errorf("error getting resource: %w", err)
	}
	return
}

func (s *Server) getAvailableActions(resourceOverrides map[string]appv1.ResourceOverride, obj *unstructured.Unstructured) ([]appv1.ResourceAction, error) {
	luaVM := lua.VM{
		ResourceOverrides: resourceOverrides,
	}

	discoveryScripts, err := luaVM.GetResourceActionDiscovery(obj)
	if err != nil {
		return nil, fmt.Errorf("error getting Lua discovery script: %w", err)
	}
	if len(discoveryScripts) == 0 {
		return []appv1.ResourceAction{}, nil
	}
	availableActions, err := luaVM.ExecuteResourceActionDiscovery(obj, discoveryScripts)
	if err != nil {
		return nil, fmt.Errorf("error executing Lua discovery script: %w", err)
	}
	return availableActions, nil
}

func (s *Server) RunResourceAction(ctx context.Context, q *application.ResourceActionRunRequest) (*application.ApplicationResponse, error) {
	resourceRequest := &application.ApplicationResourceRequest{
		Name:         q.Name,
		AppNamespace: q.AppNamespace,
		Namespace:    q.Namespace,
		ResourceName: q.ResourceName,
		Kind:         q.Kind,
		Version:      q.Version,
		Group:        q.Group,
		Project:      q.Project,
	}
	actionRequest := fmt.Sprintf("%s/%s/%s/%s", rbacpolicy.ActionAction, q.GetGroup(), q.GetKind(), q.GetAction())
	liveObj, res, a, config, err := s.getUnstructuredLiveResourceOrApp(ctx, actionRequest, resourceRequest)
	if err != nil {
		return nil, err
	}

	liveObjBytes, err := json.Marshal(liveObj)
	if err != nil {
		return nil, fmt.Errorf("error marshaling live object: %w", err)
	}

	resourceOverrides, err := s.settingsMgr.GetResourceOverrides()
	if err != nil {
		return nil, fmt.Errorf("error getting resource overrides: %w", err)
	}

	luaVM := lua.VM{
		ResourceOverrides: resourceOverrides,
	}
	action, err := luaVM.GetResourceAction(liveObj, q.GetAction())
	if err != nil {
		return nil, fmt.Errorf("error getting Lua resource action: %w", err)
	}

	newObjects, err := luaVM.ExecuteResourceAction(liveObj, action.ActionLua)
	if err != nil {
		return nil, fmt.Errorf("error executing Lua resource action: %w", err)
	}

	var app *appv1.Application
	// Only bother getting the app if we know we're going to need it for a resource permission check.
	if len(newObjects) > 0 {
		// No need for an RBAC check, we checked above that the user is allowed to run this action.
		app, err = s.appLister.Applications(s.appNamespaceOrDefault(q.GetAppNamespace())).Get(q.GetName())
		if err != nil {
			return nil, err
		}
	}

	proj, err := s.getAppProject(ctx, a, log.WithField("application", a.Name))
	if err != nil {
		return nil, err
	}

	// First, make sure all the returned resources are permitted, for each operation.
	// Also perform create with dry-runs for all create-operation resources.
	// This is performed separately to reduce the risk of only some of the resources being successfully created later.
	// TODO: when apply/delete operations would be supported for custom actions,
	// the dry-run for relevant apply/delete operation would have to be invoked as well.
	for _, impactedResource := range newObjects {
		newObj := impactedResource.UnstructuredObj
		err := s.verifyResourcePermitted(app, proj, newObj)
		if err != nil {
			return nil, err
		}
		switch impactedResource.K8SOperation {
		case lua.CreateOperation:
			createOptions := metav1.CreateOptions{DryRun: []string{"All"}}
			_, err := s.kubectl.CreateResource(ctx, config, newObj.GroupVersionKind(), newObj.GetName(), newObj.GetNamespace(), newObj, createOptions)
			if err != nil {
				return nil, err
			}
		}
	}

	// Now, perform the actual operations.
	// The creation itself is not transactional.
	// TODO: maybe create a k8s list representation of the resources,
	// and invoke create on this list resource to make it semi-transactional (there is still patch operation that is separate,
	// thus can fail separately from create).
	for _, impactedResource := range newObjects {
		newObj := impactedResource.UnstructuredObj
		newObjBytes, err := json.Marshal(newObj)
		if err != nil {
			return nil, fmt.Errorf("error marshaling new object: %w", err)
		}

		switch impactedResource.K8SOperation {
		// No default case since a not supported operation would have failed upon unmarshaling earlier
		case lua.PatchOperation:
			_, err := s.patchResource(ctx, config, liveObjBytes, newObjBytes, newObj)
			if err != nil {
				return nil, err
			}
		case lua.CreateOperation:
			_, err := s.createResource(ctx, config, newObj)
			if err != nil {
				return nil, err
			}
		}
	}

	if res == nil {
		s.logAppEvent(a, ctx, argo.EventReasonResourceActionRan, fmt.Sprintf("ran action %s", q.GetAction()))
	} else {
		s.logAppEvent(a, ctx, argo.EventReasonResourceActionRan, fmt.Sprintf("ran action %s on resource %s/%s/%s", q.GetAction(), res.Group, res.Kind, res.Name))
		s.logResourceEvent(res, ctx, argo.EventReasonResourceActionRan, fmt.Sprintf("ran action %s", q.GetAction()))
	}
	return &application.ApplicationResponse{}, nil
}

func (s *Server) patchResource(ctx context.Context, config *rest.Config, liveObjBytes, newObjBytes []byte, newObj *unstructured.Unstructured) (*application.ApplicationResponse, error) {
	diffBytes, err := jsonpatch.CreateMergePatch(liveObjBytes, newObjBytes)
	if err != nil {
		return nil, fmt.Errorf("error calculating merge patch: %w", err)
	}
	if string(diffBytes) == "{}" {
		return &application.ApplicationResponse{}, nil
	}

	// The following logic detects if the resource action makes a modification to status and/or spec.
	// If status was modified, we attempt to patch the status using status subresource, in case the
	// CRD is configured using the status subresource feature. See:
	// https://kubernetes.io/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions/#status-subresource
	// If status subresource is in use, the patch has to be split into two:
	// * one to update spec (and other non-status fields)
	// * the other to update only status.
	nonStatusPatch, statusPatch, err := splitStatusPatch(diffBytes)
	if err != nil {
		return nil, fmt.Errorf("error splitting status patch: %w", err)
	}
	if statusPatch != nil {
		_, err = s.kubectl.PatchResource(ctx, config, newObj.GroupVersionKind(), newObj.GetName(), newObj.GetNamespace(), types.MergePatchType, diffBytes, "status")
		if err != nil {
			if !apierr.IsNotFound(err) {
				return nil, fmt.Errorf("error patching resource: %w", err)
			}
			// K8s API server returns 404 NotFound when the CRD does not support the status subresource
			// if we get here, the CRD does not use the status subresource. We will fall back to a normal patch
		} else {
			// If we get here, the CRD does use the status subresource, so we must patch status and
			// spec separately. update the diffBytes to the spec-only patch and fall through.
			diffBytes = nonStatusPatch
		}
	}
	if diffBytes != nil {
		_, err = s.kubectl.PatchResource(ctx, config, newObj.GroupVersionKind(), newObj.GetName(), newObj.GetNamespace(), types.MergePatchType, diffBytes)
		if err != nil {
			return nil, fmt.Errorf("error patching resource: %w", err)
		}
	}
	return &application.ApplicationResponse{}, nil
}

func (s *Server) verifyResourcePermitted(app *appv1.Application, proj *appv1.AppProject, obj *unstructured.Unstructured) error {
	permitted, err := proj.IsResourcePermitted(schema.GroupKind{Group: obj.GroupVersionKind().Group, Kind: obj.GroupVersionKind().Kind}, obj.GetNamespace(), app.Spec.Destination, func(project string) ([]*appv1.Cluster, error) {
		clusters, err := s.db.GetProjectClusters(context.TODO(), project)
		if err != nil {
			return nil, fmt.Errorf("failed to get project clusters: %w", err)
		}
		return clusters, nil
	})
	if err != nil {
		return fmt.Errorf("error checking resource permissions: %w", err)
	}
	if !permitted {
		return fmt.Errorf("application %s is not permitted to manage %s/%s/%s in %s", app.RBACName(s.ns), obj.GroupVersionKind().Group, obj.GroupVersionKind().Kind, obj.GetName(), obj.GetNamespace())
	}

	return nil
}

func (s *Server) createResource(ctx context.Context, config *rest.Config, newObj *unstructured.Unstructured) (*application.ApplicationResponse, error) {
	_, err := s.kubectl.CreateResource(ctx, config, newObj.GroupVersionKind(), newObj.GetName(), newObj.GetNamespace(), newObj, metav1.CreateOptions{})
	if err != nil {
		return nil, fmt.Errorf("error creating resource: %w", err)
	}
	return &application.ApplicationResponse{}, nil
}

// splitStatusPatch splits a patch into two: one for a non-status patch, and the status-only patch.
// Returns nil for either if the patch doesn't have modifications to non-status, or status, respectively.
func splitStatusPatch(patch []byte) ([]byte, []byte, error) {
	var obj map[string]interface{}
	err := json.Unmarshal(patch, &obj)
	if err != nil {
		return nil, nil, err
	}
	var nonStatusPatch, statusPatch []byte
	if statusVal, ok := obj["status"]; ok {
		// calculate the status-only patch
		statusObj := map[string]interface{}{
			"status": statusVal,
		}
		statusPatch, err = json.Marshal(statusObj)
		if err != nil {
			return nil, nil, err
		}
		// remove status, and calculate the non-status patch
		delete(obj, "status")
		if len(obj) > 0 {
			nonStatusPatch, err = json.Marshal(obj)
			if err != nil {
				return nil, nil, err
			}
		}
	} else {
		// status was not modified in patch
		nonStatusPatch = patch
	}
	return nonStatusPatch, statusPatch, nil
}

func (s *Server) GetApplicationSyncWindows(ctx context.Context, q *application.ApplicationSyncWindowsQuery) (*application.ApplicationSyncWindowsResponse, error) {
	a, proj, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, q.GetProject(), q.GetAppNamespace(), q.GetName(), "")
	if err != nil {
		return nil, err
	}

	windows := proj.Spec.SyncWindows.Matches(a)
	sync, err := windows.CanSync(true)
	if err != nil {
		return nil, fmt.Errorf("invalid sync windows: %w", err)
	}

	activeWindows, err := windows.Active()
	if err != nil {
		return nil, fmt.Errorf("invalid sync windows: %w", err)
	}
	res := &application.ApplicationSyncWindowsResponse{
		ActiveWindows:   convertSyncWindows(activeWindows),
		AssignedWindows: convertSyncWindows(windows),
		CanSync:         &sync,
	}

	return res, nil
}

func (s *Server) inferResourcesStatusHealth(app *appv1.Application) {
	if app.Status.ResourceHealthSource == appv1.ResourceHealthLocationAppTree {
		tree := &appv1.ApplicationTree{}
		if err := s.cache.GetAppResourcesTree(app.Name, tree); err == nil {
			healthByKey := map[kube.ResourceKey]*appv1.HealthStatus{}
			for _, node := range tree.Nodes {
				healthByKey[kube.NewResourceKey(node.Group, node.Kind, node.Namespace, node.Name)] = node.Health
			}
			for i, res := range app.Status.Resources {
				res.Health = healthByKey[kube.NewResourceKey(res.Group, res.Kind, res.Namespace, res.Name)]
				app.Status.Resources[i] = res
			}
		}
	}
}

func convertSyncWindows(w *appv1.SyncWindows) []*application.ApplicationSyncWindow {
	if w != nil {
		var windows []*application.ApplicationSyncWindow
		for _, w := range *w {
			nw := &application.ApplicationSyncWindow{
				Kind:       &w.Kind,
				Schedule:   &w.Schedule,
				Duration:   &w.Duration,
				ManualSync: &w.ManualSync,
			}
			windows = append(windows, nw)
		}
		if len(windows) > 0 {
			return windows
		}
	}
	return nil
}

func getPropagationPolicyFinalizer(policy string) string {
	switch strings.ToLower(policy) {
	case backgroundPropagationPolicy:
		return appv1.BackgroundPropagationPolicyFinalizer
	case foregroundPropagationPolicy:
		return appv1.ForegroundPropagationPolicyFinalizer
	case "":
		return appv1.ResourcesFinalizerName
	default:
		return ""
	}
}

func (s *Server) appNamespaceOrDefault(appNs string) string {
	if appNs == "" {
		return s.ns
	} else {
		return appNs
	}
}

func (s *Server) isNamespaceEnabled(namespace string) bool {
	return security.IsNamespaceEnabled(namespace, s.ns, s.enabledNamespaces)
}

// getProjectsFromApplicationQuery gets the project names from a query. If the legacy "project" field was specified, use
// that. Otherwise, use the newer "projects" field.
func getProjectsFromApplicationQuery(q application.ApplicationQuery) []string {
	if q.Project != nil {
		return q.Project
	}
	return q.Projects
}
