package svg2png

import (
	"bytes"
	"github.com/srwiley/oksvg"
	"github.com/srwiley/rasterx"
	"image"
	"image/png"
	"io"
)

func RasterSvgToPng(r io.Reader) ([]byte, error) {
	svg, err := oksvg.ReadIconStream(r, oksvg.StrictErrorMode)
	if err != nil {
		return nil, err
	}
	w, h := int(svg.ViewBox.W), int(svg.ViewBox.H)
	img := image.NewRGBA(image.Rect(0, 0, w, h))
	scannerGV := rasterx.NewScannerGV(0, 0, img, img.Bounds())
	raster := rasterx.NewDasher(w, h, scannerGV)
	svg.Draw(raster, 1)

	b := new(bytes.Buffer)
	err = png.Encode(b, img)
	if err != nil {
		return nil, err
	}
	return b.Bytes(), nil
}