package watch

import (
	"os"
	"os/signal"
	"path/filepath"

	syscall "golang.org/x/sys/unix"

	"github.com/fsnotify/fsnotify"
)

func CreateWatchers(filePath string) (chan os.Signal, *fsnotify.Watcher, error) {
	osWatcher := newSignalWatcher(syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)

	filesystemWatcher, err := NewFilesystemWatcher(filePath)
	if err != nil {
		return nil, nil, err
	}

	return osWatcher, filesystemWatcher, nil
}

func NewFilesystemWatcher(filePath string) (*fsnotify.Watcher, error) {
	watcher, err := fsnotify.NewWatcher()
	if err != nil {
		return nil, err
	}

	var files []string
	err = filepath.Walk(filePath, func(path string, info os.FileInfo, err error) error {
		if info.IsDir() {
			files = append(files, path)
		}
		return err
	})
	if err != nil {
		return nil, err
	}

	for _, file := range files {
		err = watcher.Add(file)
		if err != nil {
			watcher.Close()
			return nil, err
		}
	}

	return watcher, nil
}

func newSignalWatcher(signals ...os.Signal) chan os.Signal {
	signalChan := make(chan os.Signal, 1)
	signal.Notify(signalChan, signals...)
	return signalChan
}

func NewConfigWatcher(filePath string) (*fsnotify.Watcher, error) {
	watcher, err := fsnotify.NewWatcher()
	if err != nil {
		return nil, err
	}

	err = watcher.Add(filePath)
	if err != nil {
		watcher.Close()
		return nil, err
	}
	return watcher, nil
}