package storage

import (
	"errors"
	"mime"
	"os"
	"path/filepath"
	"time"
)

type File struct {
	Path         string
	FSPath       string
	LastModified time.Time
	Etag         string
	Title        string
	Encodings    map[string]*os.File

	ContentType string
}

var (
	ErrEncodingNotFound = errors.New("encoding not found")
)

func NewFile(urlPath string, filename string) (*File, error) {
	f, err := os.Open(filename)
	if err != nil {
		return nil, err
	}

	stat, err := os.Stat(filename)
	if err != nil {
		return nil, err
	}

	file := &File{
		Path:         urlPath,
		FSPath:       filename,
		LastModified: stat.ModTime(),
		Etag:         "",
		Title:        filename,
		Encodings: map[string]*os.File{
			"identity": f,
		},
	}

	file.ContentType = file.getContentType()

	return file, nil
}

func (f *File) AvailableEncodings() []string {
	encs := make([]string, 0, len(f.Encodings))
	for enc := range f.Encodings {
		encs = append(encs, enc)
	}

	return encs
}

func (f *File) getContentType() string {
	ext := filepath.Ext(f.FSPath)
	if ext == "" {
		ext = ".html"
	}
	f.ContentType = mime.TypeByExtension(ext)

	return f.ContentType
}