package dashboard

import (
	"context"
	"errors"
	"fmt"
	"maps"
	"path"

	"github.com/prometheus/client_golang/prometheus"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apiserver/pkg/admission"
	"k8s.io/apiserver/pkg/registry/rest"
	genericapiserver "k8s.io/apiserver/pkg/server"
	"k8s.io/kube-openapi/pkg/common"
	"k8s.io/kube-openapi/pkg/spec3"
	"k8s.io/kube-openapi/pkg/validation/spec"

	claims "github.com/grafana/authlib/types"
	"github.com/grafana/grafana/pkg/apimachinery/utils"
	"github.com/grafana/grafana/pkg/apis/dashboard"
	"github.com/grafana/grafana/pkg/apis/dashboard/migration/conversion"
	dashboardv0alpha1 "github.com/grafana/grafana/pkg/apis/dashboard/v0alpha1"
	dashboardv1alpha1 "github.com/grafana/grafana/pkg/apis/dashboard/v1alpha1"
	dashboardv2alpha1 "github.com/grafana/grafana/pkg/apis/dashboard/v2alpha1"
	grafanaregistry "github.com/grafana/grafana/pkg/apiserver/registry/generic"
	"github.com/grafana/grafana/pkg/infra/db"
	"github.com/grafana/grafana/pkg/infra/log"
	"github.com/grafana/grafana/pkg/infra/tracing"
	"github.com/grafana/grafana/pkg/services/accesscontrol"
	"github.com/grafana/grafana/pkg/services/apiserver/builder"
	"github.com/grafana/grafana/pkg/services/dashboards"
	"github.com/grafana/grafana/pkg/services/featuremgmt"
	"github.com/grafana/grafana/pkg/services/provisioning"
	"github.com/grafana/grafana/pkg/services/search/sort"
	"github.com/grafana/grafana/pkg/setting"
	"github.com/grafana/grafana/pkg/storage/legacysql/dualwrite"
	"github.com/grafana/grafana/pkg/storage/unified/apistore"
	"github.com/grafana/grafana/pkg/storage/unified/resource"
)

var (
	_ builder.APIGroupBuilder          = (*DashboardsAPIBuilder)(nil)
	_ builder.APIGroupVersionsProvider = (*DashboardsAPIBuilder)(nil)
	_ builder.OpenAPIPostProcessor     = (*DashboardsAPIBuilder)(nil)
	_ builder.APIGroupRouteProvider    = (*DashboardsAPIBuilder)(nil)
)

// This is used just so wire has something unique to return
type DashboardsAPIBuilder struct {
	dashboardService dashboards.DashboardService
	features         featuremgmt.FeatureToggles

	accessControl                accesscontrol.AccessControl
	legacy                       *DashboardStorage
	unified                      resource.ResourceClient
	dashboardProvisioningService dashboards.DashboardProvisioningService
	scheme                       *runtime.Scheme
	search                       *SearchHandler

	log log.Logger
	reg prometheus.Registerer
}

func RegisterAPIService(
	cfg *setting.Cfg,
	features featuremgmt.FeatureToggles,
	apiregistration builder.APIRegistrar,
	dashboardService dashboards.DashboardService,
	provisioningDashboardService dashboards.DashboardProvisioningService,
	accessControl accesscontrol.AccessControl,
	provisioning provisioning.ProvisioningService,
	dashStore dashboards.Store,
	reg prometheus.Registerer,
	sql db.DB,
	tracing *tracing.TracingService,
	unified resource.ResourceClient,
	dual dualwrite.Service,
	sorter sort.Service,
) *DashboardsAPIBuilder {
	// disable dashboard api in 11.6
	/* softDelete := features.IsEnabledGlobally(featuremgmt.FlagDashboardRestore)
	dbp := legacysql.NewDatabaseProvider(sql)
	namespacer := request.GetNamespaceMapper(cfg)
	legacyDashboardSearcher := legacysearcher.NewDashboardSearchClient(dashStore, sorter)
	builder := &DashboardsAPIBuilder{
		log: log.New("grafana-apiserver.dashboards"),

		dashboardService:             dashboardService,
		features:                     features,
		accessControl:                accessControl,
		unified:                      unified,
		dashboardProvisioningService: provisioningDashboardService,
		search:                       NewSearchHandler(tracing, dual, legacyDashboardSearcher, unified, features),

		legacy: &DashboardStorage{
			Access: legacy.NewDashboardAccess(dbp, namespacer, dashStore, provisioning, softDelete, sorter),
		},
		reg: reg,
	}
	apiregistration.RegisterAPI(builder)
	return builder*/
	return nil
}

func (b *DashboardsAPIBuilder) GetGroupVersions() []schema.GroupVersion {
	return []schema.GroupVersion{
		dashboardv0alpha1.DashboardResourceInfo.GroupVersion(),
		dashboardv1alpha1.DashboardResourceInfo.GroupVersion(),
		dashboardv2alpha1.DashboardResourceInfo.GroupVersion(),
	}
}

func (b *DashboardsAPIBuilder) InstallSchema(scheme *runtime.Scheme) error {
	b.scheme = scheme
	if err := dashboardv0alpha1.AddToScheme(scheme); err != nil {
		return err
	}
	if err := dashboardv1alpha1.AddToScheme(scheme); err != nil {
		return err
	}
	if err := dashboardv2alpha1.AddToScheme(scheme); err != nil {
		return err
	}

	// Register the explicit conversions
	if err := conversion.RegisterConversions(scheme); err != nil {
		return err
	}

	return scheme.SetVersionPriority(b.GetGroupVersions()...)
}

// Validate will prevent deletion of provisioned dashboards, unless the grace period is set to 0, indicating a force deletion
func (b *DashboardsAPIBuilder) Validate(ctx context.Context, a admission.Attributes, o admission.ObjectInterfaces) (err error) {
	op := a.GetOperation()
	if op == admission.Delete {
		obj := a.GetOperationOptions()
		deleteOptions, ok := obj.(*metav1.DeleteOptions)
		if !ok {
			return fmt.Errorf("expected v1.DeleteOptions")
		}

		if deleteOptions.GracePeriodSeconds == nil || *deleteOptions.GracePeriodSeconds != 0 {
			nsInfo, err := claims.ParseNamespace(a.GetNamespace())
			if err != nil {
				return fmt.Errorf("%v: %w", "failed to parse namespace", err)
			}

			provisioningData, err := b.dashboardProvisioningService.GetProvisionedDashboardDataByDashboardUID(ctx, nsInfo.OrgID, a.GetName())
			if err != nil {
				if errors.Is(err, dashboards.ErrProvisionedDashboardNotFound) ||
					errors.Is(err, dashboards.ErrDashboardNotFound) ||
					apierrors.IsNotFound(err) {
					return nil
				}

				return fmt.Errorf("%v: %w", "delete hook failed to check if dashboard is provisioned", err)
			}

			if provisioningData != nil {
				return dashboards.ErrDashboardCannotDeleteProvisionedDashboard
			}
		}
	}

	return nil
}

func (b *DashboardsAPIBuilder) UpdateAPIGroupInfo(apiGroupInfo *genericapiserver.APIGroupInfo, opts builder.APIGroupOptions) error {
	storageOpts := apistore.StorageOptions{
		RequireDeprecatedInternalID: true,
	}

	// Split dashboards when they are large
	var largeObjects apistore.LargeObjectSupport
	if b.features.IsEnabledGlobally(featuremgmt.FlagUnifiedStorageBigObjectsSupport) {
		largeObjects = NewDashboardLargeObjectSupport(opts.Scheme)
		storageOpts.LargeObjectSupport = largeObjects
	}
	opts.StorageOptions(dashboardv0alpha1.DashboardResourceInfo.GroupResource(), storageOpts)

	// v0alpha1
	if err := b.storageForVersion(apiGroupInfo, opts, largeObjects,
		dashboardv0alpha1.DashboardResourceInfo,
		dashboardv0alpha1.LibraryPanelResourceInfo,
		func(obj runtime.Object, access *dashboard.DashboardAccess) (v runtime.Object, err error) {
			dto := &dashboardv0alpha1.DashboardWithAccessInfo{}
			dash, ok := obj.(*dashboardv0alpha1.Dashboard)
			if ok {
				dto.Dashboard = *dash
			}
			if access != nil {
				err = b.scheme.Convert(access, &dto.Access, nil)
			}
			return dto, err
		}); err != nil {
		return err
	}

	// v1alpha1
	if err := b.storageForVersion(apiGroupInfo, opts, largeObjects,
		dashboardv1alpha1.DashboardResourceInfo,
		dashboardv1alpha1.LibraryPanelResourceInfo,
		func(obj runtime.Object, access *dashboard.DashboardAccess) (v runtime.Object, err error) {
			dto := &dashboardv1alpha1.DashboardWithAccessInfo{}
			dash, ok := obj.(*dashboardv1alpha1.Dashboard)
			if ok {
				dto.Dashboard = *dash
			}
			if access != nil {
				err = b.scheme.Convert(access, &dto.Access, nil)
			}
			return dto, err
		}); err != nil {
		return err
	}

	// v2alpha1
	if err := b.storageForVersion(apiGroupInfo, opts, largeObjects,
		dashboardv2alpha1.DashboardResourceInfo,
		dashboardv2alpha1.LibraryPanelResourceInfo,
		func(obj runtime.Object, access *dashboard.DashboardAccess) (v runtime.Object, err error) {
			dto := &dashboardv2alpha1.DashboardWithAccessInfo{}
			dash, ok := obj.(*dashboardv2alpha1.Dashboard)
			if ok {
				dto.Dashboard = *dash
			}
			if access != nil {
				err = b.scheme.Convert(access, &dto.Access, nil)
			}
			return dto, err
		}); err != nil {
		return err
	}

	return nil
}

func (b *DashboardsAPIBuilder) storageForVersion(
	apiGroupInfo *genericapiserver.APIGroupInfo,
	opts builder.APIGroupOptions,
	largeObjects apistore.LargeObjectSupport,
	dashboards utils.ResourceInfo,
	libraryPanels utils.ResourceInfo,
	newDTOFunc dtoBuilder,
) error {
	// Register the versioned storage
	storage := map[string]rest.Storage{}
	apiGroupInfo.VersionedResourcesStorageMap[dashboards.GroupVersion().Version] = storage

	legacyStore, err := b.legacy.NewStore(dashboards, opts.Scheme, opts.OptsGetter, b.reg)
	if err != nil {
		return err
	}

	store, err := grafanaregistry.NewRegistryStore(opts.Scheme, dashboards, opts.OptsGetter)
	if err != nil {
		return err
	}

	gr := dashboards.GroupResource()
	storage[dashboards.StoragePath()], err = opts.DualWriteBuilder(gr, legacyStore, store)
	if err != nil {
		return err
	}

	if b.features.IsEnabledGlobally(featuremgmt.FlagKubernetesRestore) {
		storage[dashboards.StoragePath("restore")] = NewRestoreConnector(b.unified, gr)
		storage[dashboards.StoragePath("latest")] = NewLatestConnector(b.unified, gr)
	}

	// Register the DTO endpoint that will consolidate all dashboard bits
	storage[dashboards.StoragePath("dto")], err = NewDTOConnector(
		storage[dashboards.StoragePath()].(rest.Getter),
		largeObjects,
		b.legacy.Access,
		b.unified,
		b.accessControl,
		opts.Scheme,
		newDTOFunc,
	)
	if err != nil {
		return err
	}

	// Expose read only library panels
	storage[libraryPanels.StoragePath()] = &LibraryPanelStore{
		Access:       b.legacy.Access,
		ResourceInfo: libraryPanels,
	}

	return nil
}

func (b *DashboardsAPIBuilder) GetOpenAPIDefinitions() common.GetOpenAPIDefinitions {
	return func(ref common.ReferenceCallback) map[string]common.OpenAPIDefinition {
		defs := dashboardv0alpha1.GetOpenAPIDefinitions(ref)
		maps.Copy(defs, dashboardv1alpha1.GetOpenAPIDefinitions(ref))
		maps.Copy(defs, dashboardv2alpha1.GetOpenAPIDefinitions(ref))
		return defs
	}
}

func (b *DashboardsAPIBuilder) PostProcessOpenAPI(oas *spec3.OpenAPI) (*spec3.OpenAPI, error) {
	// The plugin description
	oas.Info.Description = "Grafana dashboards as resources"

	for _, gv := range b.GetGroupVersions() {
		version := gv.Version
		// Hide cluster-scoped resources
		root := path.Join("/apis/", dashboardv0alpha1.GROUP, version)
		delete(oas.Paths.Paths, path.Join(root, "dashboards"))
		delete(oas.Paths.Paths, path.Join(root, "watch", "dashboards"))

		if version == dashboardv0alpha1.VERSION {
			sub := oas.Paths.Paths[path.Join(root, "search", "{name}")]
			oas.Paths.Paths[path.Join(root, "search")] = sub
			delete(oas.Paths.Paths, path.Join(root, "search", "{name}"))
		}
	}

	return oas, nil
}

func (b *DashboardsAPIBuilder) GetAPIRoutes() *builder.APIRoutes {
	defs := b.GetOpenAPIDefinitions()(func(path string) spec.Ref { return spec.Ref{} })
	return b.search.GetAPIRoutes(defs)
}