// Package cleaner is a background process that compares the kubernetes namespace list with the folders in the local git home directory, deleting what's not in the namespace list
package cleaner

import (
	"log"

	"k8s.io/kubernetes/pkg/api"

	"github.com/deis/builder/pkg/k8s"
	"github.com/deis/builder/pkg/sys"
)

const (
	dotGitSuffix = ".git"
)

// Run starts the deleted app cleaner. This function listens to the Kubernetes event stream for events that indicate namespaces that were `DELETED`.
// If the namespace name matches a folder on the local filesystem, this func deletes that folder.
// Note that this function blocks until the watcher returned by `nsLister.Watch` is closed, so you should launch it in a goroutine.
func Run(gitHome string, nsLister k8s.NamespaceWatcher, fs sys.FS) error {
	watcher, err := nsLister.Watch(nil, nil, "")
	if err != nil {
		log.Printf("unable to get watch events (%s)", err)
	}
	for {
		event := <-watcher.ResultChan()
		if event.Type == "DELETED" {
			switch event.Object.(type) {
			case (*api.Namespace):
				namespace := event.Object.(*api.Namespace)
				appToDelete := gitHome + "/" + namespace.ObjectMeta.Name + dotGitSuffix
				if err := fs.RemoveAll(appToDelete); err != nil {
					log.Printf("Cleaner error removing deleted app %s (%s)", appToDelete, err)
				}
			default:
			}
		}
	}

}