package fileutil

import (
	"os"
	"path/filepath"
	"strings"
)

var (
	standardMediaExts = map[string]struct{}{
		".mp3": {}, ".flac": {}, ".wav": {}, ".m4a": {},
		".ogg": {}, ".opus": {}, ".aac": {}, ".wma": {},
		".ape": {}, ".alac": {}, ".dsf": {}, ".dff": {},
	}
	encryptedMediaExts = map[string]struct{}{
		".kgma": {}, ".kgm": {},
		".ncm":  {},
		".qmc": {}, ".qmc0": {}, ".qmc3": {}, ".qmcflac": {}, ".qmcogg": {},
		".mgg": {}, ".mflac": {},
		".tm": {}, ".tkm": {},
		".xiami": {}, ".xm": {},
		".ximalaya": {}, ".xmly": {},
		".x2m": {}, ".x3m": {},
		".kwm": {},
	}
	videoMediaExts = map[string]struct{}{
		".mp4": {}, ".mkv": {}, ".avi": {}, ".mov": {}, ".flv": {},
	}
)

// IsMediaFile reports whether the file name looks like a media file this tool handles.
func IsMediaFile(fileName string) bool {
	ext := strings.ToLower(filepath.Ext(fileName))
	if _, ok := standardMediaExts[ext]; ok {
		return true
	}
	if _, ok := encryptedMediaExts[ext]; ok {
		return true
	}
	if _, ok := videoMediaExts[ext]; ok {
		return true
	}
	return false
}

// FileExist reports whether path exists.
func FileExist(path string) bool {
	_, err := os.Stat(path)
	return err == nil
}