/*
Copyright 2019 The Fission 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 httptrigger

import (
	"fmt"

	"github.com/hashicorp/go-multierror"
	"github.com/pkg/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"github.com/fission/fission/pkg/controller/client"
	"github.com/fission/fission/pkg/fission-cli/cliwrapper/cli"
	"github.com/fission/fission/pkg/fission-cli/cmd"
)

type DeleteSubCommand struct {
	client       *client.Client
	triggerName  string
	functionName string
	namespace    string
}

func Delete(flags cli.Input) error {
	opts := DeleteSubCommand{
		client: cmd.GetServer(flags),
	}
	return opts.do(flags)
}

func (opts *DeleteSubCommand) do(flags cli.Input) error {
	err := opts.complete(flags)
	if err != nil {
		return err
	}
	return opts.run(flags)
}

// complete creates a environment objects and populates it with default value and CLI inputs.
func (opts *DeleteSubCommand) complete(flags cli.Input) error {
	opts.triggerName = flags.String("name")
	opts.functionName = flags.String("function")
	if len(opts.triggerName) == 0 && len(opts.functionName) == 0 {
		return errors.New("need --name or --function")
	} else if len(opts.triggerName) > 0 && len(opts.functionName) > 0 {
		return errors.New("need either of --name or --function and not both arguments")
	}
	opts.namespace = flags.String("triggerNamespace")
	return nil
}

func (opts *DeleteSubCommand) run(flags cli.Input) error {
	triggers, err := opts.client.HTTPTriggerList(opts.namespace)
	if err != nil {
		return errors.Wrap(err, "error getting HTTP trigger list")
	}

	var triggersToDelete []string

	if len(opts.functionName) > 0 {
		for _, trigger := range triggers {
			// TODO: delete canary http triggers as well.
			if trigger.Spec.FunctionReference.Name == opts.functionName {
				triggersToDelete = append(triggersToDelete, trigger.Metadata.Name)
			}
		}
	} else {
		triggersToDelete = []string{opts.triggerName}
	}

	errs := &multierror.Error{}

	for _, name := range triggersToDelete {
		err := opts.client.HTTPTriggerDelete(&metav1.ObjectMeta{
			Name:      name,
			Namespace: opts.namespace,
		})
		if err != nil {
			errs = multierror.Append(errs, err)
		} else {
			fmt.Printf("trigger '%v' deleted\n", name)
		}
	}

	if errs.ErrorOrNil() != nil {
		return errors.Wrap(errs.ErrorOrNil(), "error deleting trigger(s)")
	}

	return nil
}