package storage

import (
	"os"
	"path/filepath"
)

type Storage interface {
	Stat(path string) (os.FileInfo, error)
	Open(path string) (*os.File, error)
	Create(path string) (*os.File, error)
	Remove(path string) error
	Rename(oldPath, newPath string) error
	MkdirAll(path string) error
	List(path string) ([]os.FileInfo, error)
}

type Local struct{ Root string }

func (s Local) real(path string) string               { return filepath.Join(s.Root, filepath.Clean("/"+path)) }
func (s Local) Stat(path string) (os.FileInfo, error) { return os.Stat(s.real(path)) }
func (s Local) Open(path string) (*os.File, error)    { return os.Open(s.real(path)) }
func (s Local) Create(path string) (*os.File, error) {
	p := s.real(path)
	if err := os.MkdirAll(filepath.Dir(p), 0755); err != nil {
		return nil, err
	}
	return os.Create(p)
}
func (s Local) Remove(path string) error   { return os.RemoveAll(s.real(path)) }
func (s Local) Rename(a, b string) error   { return os.Rename(s.real(a), s.real(b)) }
func (s Local) MkdirAll(path string) error { return os.MkdirAll(s.real(path), 0755) }
func (s Local) List(path string) ([]os.FileInfo, error) {
	f, err := os.Open(s.real(path))
	if err != nil {
		return nil, err
	}
	defer f.Close()
	return f.Readdir(-1)
}