package cushion

import (
	"context"
	"fmt"
	"time"

	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apimachinery/pkg/types"
	"sigs.k8s.io/controller-runtime/pkg/client"

	dsapi "edge-infra.dev/pkg/edge/datasync/apis/v1alpha1"
	"edge-infra.dev/pkg/edge/datasync/couchdb"
)

// migrateCushionK8sDBs migrates the cushion k8s dbs to avoid naming collisions
func migrateCushionK8sDBs(ctx context.Context, cl client.Client) error {
	k8sDBs := &dsapi.CouchDBDatabaseList{}
	r, err := labels.NewRequirement(componentLabel, "!", []string{})
	if err != nil {
		return fmt.Errorf("error creating componentLabel requirement for migration: %w", err)
	}
	err = cl.List(ctx, k8sDBs, &client.ListOptions{
		LabelSelector: labels.NewSelector().Add(*r),
		Namespace:     cushionNamespace,
	})
	if err != nil {
		return fmt.Errorf("error listing k8s dbs for migration: %w", err)
	}
	if len(k8sDBs.Items) == 0 {
		return nil // already migrated
	}
	for _, k8sDB := range k8sDBs.Items {
		if err := migrateCushionK8sDB(ctx, cl, &k8sDB); err != nil {
			return fmt.Errorf("error migrating k8s db: %w", err)
		}
		time.Sleep(1 * time.Second) // avoid rate limiting
	}
	return nil
}

func migrateCushionK8sDB(ctx context.Context, cl client.Client, c *dsapi.CouchDBDatabase) error {
	nn := types.NamespacedName{Name: K8sDBName(c.Spec.Name), Namespace: cushionNamespace}
	// technically db names are already normalized
	k8sDB := newCouchDBDatabase(nn, normalizeDBName(c.Spec.Name), couchdb.Namespace)
	if err := cl.Create(ctx, k8sDB); err != nil && client.IgnoreAlreadyExists(err) != nil {
		return fmt.Errorf("error creating k8s db: %w", err)
	}
	// finally delete the old resource
	if err := cl.Delete(ctx, c); err != nil {
		return fmt.Errorf("error deleting old CouchDBDatabase resource: %w", err)
	}
	return nil
}