package osutil

import (
	"io/fs"
	"os"
)

// FS implements [fs.FS], [fs.StatFS], and [fs.ReadFileFS]
// using package [os].
//
// This filesystem does not respect [fs.ValidPath] rules,
// and fails [testing/fstest.TestFS]!
//
// Still, it can be a useful tool to unify implementations
// that can access either the [os] filesystem or an [fs.FS].
// It's OK to use this to open files, but you should avoid
// opening directories, resolving paths, or walking the file system.
type FS struct{}

// Open implements [fs.FS].
func (FS) Open(name string) (fs.File, error) {
	return OpenFile(name, os.O_RDONLY, 0)
}

// ReadFileFS implements [fs.StatFS].
func (FS) Stat(name string) (fs.FileInfo, error) {
	return os.Stat(name)
}

// ReadFile implements [fs.ReadFileFS].
func (FS) ReadFile(name string) ([]byte, error) {
	return os.ReadFile(name)
}