package utio

import (
	"image"
	"image/jpeg"
	"io"
)

// JPEG creates a JPEG encoder/decoder for m, m is only required for encoding.
func JPEG(m image.Image) Imager {
	return JPEGOpts(m, 95)
}

func JPEGOpts(m image.Image, quality int) Imager {
	return &jpeger{imager{m}, quality}
}

type jpeger struct {
	imager

	quality int
}

func (j *jpeger) Encode(w io.Writer) error {
	return jpeg.Encode(w, j.m, &jpeg.Options{Quality: j.quality})
}

func (j *jpeger) Decode(r io.Reader) error {
	var m, err = jpeg.Decode(r)
	if nil != err {
		return err
	}
	j.m = m
	return nil
}

// LoadJPEG loads a JPEG image from the supplied path.
func LoadJPEG(path string) (image.Image, error) {
	var j = JPEG(nil)
	var err = DecodeFile(path, j)
	if nil != err {
		return nil, err
	}
	return j.Image(), nil
}

// SaveJPEG writes an image as JPEG to the supplied path.
func SaveJPEG(path string, m image.Image) error {
	return EncodeFile(path, JPEG(m))
}