// Copyright 2017 The kubecfg 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 kubecfg

import (
	"context"
	"fmt"
	"sort"

	log "github.com/sirupsen/logrus"
	"k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/api/meta"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	"k8s.io/client-go/discovery"
	"k8s.io/client-go/dynamic"

	"code.hackerspace.pl/hscloud/cluster/tools/kartongips/utils"
)

// DeleteCmd represents the delete subcommand
type DeleteCmd struct {
	Client           dynamic.Interface
	Mapper           meta.RESTMapper
	Discovery        discovery.DiscoveryInterface
	DefaultNamespace string

	GracePeriod int64
}

func (c DeleteCmd) Run(ctx context.Context, apiObjects []*unstructured.Unstructured) error {
	version, err := utils.FetchVersion(c.Discovery)
	if err != nil {
		version = utils.GetDefaultVersion()
		log.Warnf("Unable to parse server version. Received %v. Using default %s", err, version.String())
	}

	log.Infof("Fetching schemas for %d resources", len(apiObjects))
	depOrder, err := utils.DependencyOrder(c.Discovery, c.Mapper, apiObjects)
	if err != nil {
		return err
	}
	sort.Sort(sort.Reverse(depOrder))

	deleteOpts := metav1.DeleteOptions{}
	if version.Compare(1, 6) < 0 {
		// 1.5.x option
		boolFalse := false
		deleteOpts.OrphanDependents = &boolFalse
	} else {
		// 1.6.x option (NB: Background is broken)
		fg := metav1.DeletePropagationForeground
		deleteOpts.PropagationPolicy = &fg
	}
	if c.GracePeriod >= 0 {
		deleteOpts.GracePeriodSeconds = &c.GracePeriod
	}

	for _, obj := range apiObjects {
		desc := fmt.Sprintf("%s %s", utils.ResourceNameFor(c.Mapper, obj), utils.FqName(obj))
		log.Info("Deleting ", desc)

		client, err := utils.ClientForResource(c.Client, c.Mapper, obj, c.DefaultNamespace)
		if err != nil {
			return err
		}

		err = client.Delete(ctx, obj.GetName(), deleteOpts)
		if err != nil && !errors.IsNotFound(err) {
			return fmt.Errorf("Error deleting %s: %s", desc, err)
		}

		log.Debug("Deleted object: ", obj)
	}

	return nil
}