package stdos

import (
	"net/http"
	"os"
	"path"

	"github.com/markbates/pkger/here"
	"github.com/markbates/pkger/pkging"
)

var _ pkging.File = &File{}

type File struct {
	*os.File
	info   *pkging.FileInfo
	her    here.Info
	path   pkging.Path
	pkging pkging.Pkger
}

func NewFile(fx pkging.Pkger, osf *os.File) (*File, error) {
	name := osf.Name()
	pt, err := fx.Parse(name)
	if err != nil {
		return nil, err
	}
	info, err := osf.Stat()
	if err != nil {
		return nil, err
	}

	f := &File{
		File:   osf,
		path:   pt,
		pkging: fx,
	}
	f.info = pkging.WithName(pt.Name, info)

	her, err := here.Package(pt.Pkg)
	if err != nil {
		return nil, err
	}
	f.her = her
	return f, nil
}

func (f *File) Close() error {
	return f.File.Close()
}

func (f *File) Abs() (string, error) {
	return f.pkging.AbsPath(f.path)
}

func (f *File) Info() here.Info {
	return f.her
}

func (f *File) Name() string {
	return f.info.Name()
}

type HTTP struct {
	pkging.File
	osf *os.File
}

func (f *HTTP) Readdir(count int) ([]os.FileInfo, error) {
	osinfos, err := f.osf.Readdir(count)
	if err != nil {
		return nil, err
	}

	infos := make([]os.FileInfo, len(osinfos))
	for i, info := range osinfos {
		infos[i] = pkging.WithRelName(info.Name(), info)
	}
	return infos, err
}

func (f *File) Open(name string) (http.File, error) {
	fp := path.Join(f.Path().Name, name)
	f2, err := f.pkging.Open(fp)
	if err != nil {
		return nil, err
	}
	return &HTTP{File: f2, osf: f.File}, nil
}

func (f *File) Path() pkging.Path {
	return f.path
}

func (f *File) Stat() (os.FileInfo, error) {
	if f.info != nil {
		return f.info, nil
	}

	nf, err := NewFile(f.pkging, f.File)
	if err != nil {
		return nil, err
	}
	(*f) = *nf
	return f.info, nil
}