package metadatabackup

import (
	"context"
	"fmt"
	"github.com/pingcap/tep/pkg/rbac"
	"time"

	"github.com/pingcap/tep/db/entity"
	"github.com/pingcap/tep/pkg/apis/apiserver"
	"github.com/pingcap/tep/pkg/operator"
	store "github.com/pingcap/tep/pkg/registry/apiserver"
	"github.com/pingcap/tep/pkg/utils"
	"github.com/pingcap/tep/pkg/utils/validate"
	"github.com/pingcap/tidb-operator/pkg/label"
	batchv1 "k8s.io/api/batch/v1"
	"k8s.io/apimachinery/pkg/api/errors"
	metainternalversion "k8s.io/apimachinery/pkg/apis/meta/internalversion"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apiserver/pkg/registry/rest"
)

type Storage struct {
	store         *store.Store
	groupResource schema.GroupResource
}

func NewStorage(store *store.Store, groupResource schema.GroupResource) *Storage {
	return &Storage{
		store:         store,
		groupResource: groupResource,
	}
}

func (s *Storage) Kind() string {
	return "MetadataBackup"
}

func (s *Storage) New() runtime.Object {
	return &apiserver.MetadataBackup{}
}

func (s *Storage) Create(ctx context.Context, obj runtime.Object, createValidation rest.ValidateObjectFunc, options *metav1.CreateOptions) (runtime.Object, error) {
	var err error
	var metadataBackup *apiserver.MetadataBackup
	var job *batchv1.Job
	startTime := time.Now()
	namespace := s.store.Namespace
	operatorName := utils.GetAPIUsername(ctx)
	if !rbac.CanOperate(s.store.DB, operatorName, rbac.PlatformOperation) {
		return nil, errors.NewForbidden(s.groupResource, operatorName, fmt.Errorf("permission denied"))
	}
	backup := obj.(*apiserver.MetadataBackup)
	//if no bucket field, use the default one
	if backup.S3.Bucket == "" {
		backup.S3.Bucket = operator.MetadataBucketName
	}

	if err = validate.ValidateMetadataBackup(backup); err != nil {
		return nil, errors.NewBadRequest(err.Error())
	}

	if job, err = s.store.Controller().CreateMetadataBackupJob(s.store.MetadataBackupImage, namespace, s.store.DSN, backup); err != nil {
		return nil, errors.NewInternalError(err)
	}
	if metadataBackup, err = s.store.Controller().AssembleMetadataBackup(job); err != nil {
		return nil, errors.NewInternalError(err)
	}

	if err = s.store.AddEvent(&utils.Event{
		UserID:         operatorName,
		Payload:        backup,
		OperationType:  entity.CreateOperation,
		ManagementType: entity.PlatformManagement,
		CostTime:       time.Now().Sub(startTime).Nanoseconds(),
	}); err != nil {
		return nil, errors.NewInternalError(err)
	}

	return metadataBackup, nil
}

func (s *Storage) Delete(ctx context.Context, name string, deleteValidation rest.ValidateObjectFunc, options *metav1.DeleteOptions) (runtime.Object, bool, error) {
	startTime := time.Now()
	operatorName := utils.GetAPIUsername(ctx)
	if !rbac.CanOperate(s.store.DB, operatorName, rbac.PlatformOperation) {
		return nil, false, errors.NewForbidden(s.groupResource, operatorName, fmt.Errorf("permission denied"))
	}
	var err error
	namespace := s.store.Namespace
	if err = s.store.Controller().DeleteBackupJob(name, namespace); err != nil {
		msg := fmt.Errorf("failed to delete backup[%s]. err: %v", namespace, err)
		if errors.IsNotFound(err) {
			return nil, false, errors.NewNotFound(s.groupResource, fmt.Sprintf("backup %s is not found %s", name))
		}
		return nil, false, errors.NewInternalError(msg)
	}
	if err = s.store.AddEvent(&utils.Event{
		UserID:         operatorName,
		Payload:        name,
		OperationType:  entity.OperateOperation,
		ManagementType: entity.PlatformManagement,
		CostTime:       time.Now().Sub(startTime).Nanoseconds(),
	}); err != nil {
		return nil, false, err
	}
	return nil, true, nil
}

func (s *Storage) List(ctx context.Context, options *metainternalversion.ListOptions, extraOptions runtime.Object) (runtime.Object, error) {
	var backupCRs *batchv1.JobList
	var itemTotal int64
	var err error
	var metadataBackup *apiserver.MetadataBackup
	var backupCRList []apiserver.MetadataBackup

	namespace := s.store.Namespace
	extraOption := extraOptions.(*apiserver.BackupListOptions)
	listOpts := metav1.ListOptions{
		LabelSelector: labels.SelectorFromSet(
			map[string]string{
				label.ComponentLabelKey: operator.MetadataBackupComponentLabel,
			},
		).String(),
	}
	if backupCRs, err = s.store.Controller().ListJobs(namespace, listOpts); err != nil {
		msg := fmt.Errorf("failed to list backupCR namespace[%s]. err: %v", namespace, err)
		return nil, errors.NewInternalError(msg)
	}
	var startTime, endTime int64
	var page, itemsPerPage int

	if extraOption.StartTimeInSec != 0 {
		startTime = extraOption.StartTimeInSec
	} else {
		startTime = time.Now().Unix() - 24*3600
	}

	if extraOption.EndTimeInSec != 0 {
		endTime = extraOption.EndTimeInSec
	} else {
		endTime = time.Now().Unix()
	}

	if extraOption.ItemsPerPage != 0 {
		itemsPerPage = extraOption.ItemsPerPage
	} else {
		itemsPerPage = 10
	}

	if extraOption.Page != 0 {
		page = extraOption.Page
	} else {
		page = 1
	}

	for _, backupCR := range backupCRs.Items {
		if startTime < backupCR.CreationTimestamp.Unix() && backupCR.CreationTimestamp.Unix() < endTime {
			if metadataBackup, err = s.store.Controller().AssembleMetadataBackup(&backupCR); err != nil {
				continue
			}
			backupCRList = append(backupCRList, *metadataBackup)
		}
	}

	itemTotal = int64(len(backupCRList))

	return &apiserver.MetadataBackupList{
		Items: utils.Pagination(page, itemsPerPage, backupCRList).([]apiserver.MetadataBackup),
		Total: itemTotal,
	}, nil
}

func (s *Storage) NewList() runtime.Object {
	return &apiserver.MetadataBackupList{}
}

func (s *Storage) NamespaceScoped() bool {
	return false
}

func (s *Storage) NewGetOptions() (runtime.Object, bool, string) {
	return &apiserver.MetadataBackup{}, true, ""
}

func (s *Storage) NewExtraListOptions() runtime.Object {
	return &apiserver.BackupListOptions{}
}