/*
Copyright 2018 The CDI Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package operator

import (
	"context"
	"fmt"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/client-go/kubernetes"
	"k8s.io/klog/v2"

	"kubevirt.io/containerized-data-importer/pkg/util"

	"sigs.k8s.io/controller-runtime/pkg/client"
)

const (
	// ConfigMapName is the name of the CDI Operator config map
	// used to determine which CDI instance is "active"
	// and maybe other stuff some day in the future
	ConfigMapName = "cdi-config"
)

//SetOwnerRuntime makes the current "active" CDI CR the owner of the object using runtime lib client
func SetOwnerRuntime(client client.Client, object metav1.Object) error {
	namespace := util.GetNamespace()
	configMap := &corev1.ConfigMap{}
	if err := client.Get(context.TODO(), types.NamespacedName{Name: ConfigMapName, Namespace: namespace}, configMap); err != nil {
		klog.Warningf("ConfigMap %s does not exist, so not assigning owner", ConfigMapName)
		return nil
	}
	return SetConfigAsOwner(configMap, object)
}

// SetOwner makes the current "active" CDI CR the owner of the object
func SetOwner(client kubernetes.Interface, object metav1.Object) error {
	namespace := util.GetNamespace()
	configMap, err := client.CoreV1().ConfigMaps(namespace).Get(context.TODO(), ConfigMapName, metav1.GetOptions{})
	if err != nil {
		klog.Warningf("ConfigMap %s does not exist, so not assigning owner", ConfigMapName)
		return nil
	}
	return SetConfigAsOwner(configMap, object)
}

// SetConfigAsOwner sets the passed in config map as owner of the object
func SetConfigAsOwner(configMap *corev1.ConfigMap, object metav1.Object) error {
	configMapOwner := getController(configMap.GetOwnerReferences())

	if configMapOwner == nil {
		return fmt.Errorf("configmap has no owner")
	}

	for _, o := range object.GetOwnerReferences() {
		if o.Controller != nil && *o.Controller {
			if o.UID == configMapOwner.UID {
				// already set to current obj
				return nil
			}

			return fmt.Errorf("object %+v already owned by %+v", object, o)
		}
	}

	object.SetOwnerReferences(append(object.GetOwnerReferences(), *configMapOwner))

	return nil
}

func getController(owners []metav1.OwnerReference) *metav1.OwnerReference {
	for _, owner := range owners {
		if owner.Controller != nil && *owner.Controller {
			return &owner
		}
	}
	return nil
}
