// Copyright © 2014 Steve Francia <spf@spf13.com>.

// Copyright 2013 tsuru authors. All rights reserved.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

package afero

import (

	"os"

	"time"

)

var _ Lstater = (*OsFs)(nil)

// OsFs is a Fs implementation that uses functions provided by the os package.

//

// For details in any method, check the documentation of the os package

// (http://golang.org/pkg/os/).

type OsFs struct{}

func NewOsFs() Fs {

	return &OsFs{}

}

func (OsFs) Name() string { return "OsFs" }

func (OsFs) Create(name string) (File, error) {

	f, e := os.Create(name)

	if f == nil {

		// while this looks strange, we need to return a bare nil (of type nil) not

		// a nil value of type *os.File or nil won't be nil

		return nil, e

	}

	return f, e

}

func (OsFs) Mkdir(name string, perm os.FileMode) error {

	return os.Mkdir(name, perm)

}

func (OsFs) MkdirAll(path string, perm os.FileMode) error {

	return os.MkdirAll(path, perm)

}

func (OsFs) Open(name string) (File, error) {

	f, e := os.Open(name)

	if f == nil {

		// while this looks strange, we need to return a bare nil (of type nil) not

		// a nil value of type *os.File or nil won't be nil

		return nil, e

	}

	return f, e

}

func (OsFs) OpenFile(name string, flag int, perm os.FileMode) (File, error) {

	f, e := os.OpenFile(name, flag, perm)

	if f == nil {

		// while this looks strange, we need to return a bare nil (of type nil) not

		// a nil value of type *os.File or nil won't be nil

		return nil, e

	}

	return f, e

}

func (OsFs) Remove(name string) error {

	return os.Remove(name)

}

func (OsFs) RemoveAll(path string) error {

	return os.RemoveAll(path)

}

func (OsFs) Rename(oldname, newname string) error {

	return os.Rename(oldname, newname)

}

func (OsFs) Stat(name string) (os.FileInfo, error) {

	return os.Stat(name)

}

func (OsFs) Chmod(name string, mode os.FileMode) error {

	return os.Chmod(name, mode)

}

func (OsFs) Chown(name string, uid, gid int) error {

	return os.Chown(name, uid, gid)

}

func (OsFs) Chtimes(name string, atime time.Time, mtime time.Time) error {

	return os.Chtimes(name, atime, mtime)

}

func (OsFs) LstatIfPossible(name string) (os.FileInfo, bool, error) {

	fi, err := os.Lstat(name)

	return fi, true, err

}

func (OsFs) SymlinkIfPossible(oldname, newname string) error {

	return os.Symlink(oldname, newname)

}

func (OsFs) ReadlinkIfPossible(name string) (string, error) {

	return os.Readlink(name)

}