// Package format describes the file types the gallery can show.
package format

import (
	"io"
	"path/filepath"
	"strings"
	"time"
)

type Kind int

const (
	KindImage Kind = iota
)

// Meta holds display metadata. Width and Height are after EXIF orientation.
type Meta struct {
	Width, Height int
	Taken         time.Time
	Camera, Lens  string
	Aperture      string
	Shutter       string
	ISO           int
}

type Format interface {
	Name() string
	Match(path string) bool
	Metadata(path string) (Meta, error)
	Resize(src string, width int, dst io.Writer) error
	Kind() Kind
}

// Registry resolves a path to the first registered Format that matches it.
type Registry struct {
	formats []Format
}

func (r *Registry) Register(f Format) {
	r.formats = append(r.formats, f)
}

func (r *Registry) Lookup(path string) Format {
	for _, f := range r.formats {
		if f.Match(path) {
			return f
		}
	}
	return nil
}

func hasExt(path string, exts []string) bool {
	ext := strings.ToLower(filepath.Ext(path))
	for _, e := range exts {
		if ext == e {
			return true
		}
	}
	return false
}