meowlib/contactcard.go

package meowlib

import (
	"bytes"
	"compress/gzip"
	"fmt"
	"image"
	"image/color"
	"image/png"
	"log"
	"math"
	"os"

	"github.com/makiuchi-d/gozxing"
	"github.com/makiuchi-d/gozxing/qrcode"
	"google.golang.org/protobuf/proto"
)

func ServerFromUrl(url string) *Server {
	var s Server
	s.Url = url
	return &s
}

func (Contact *ContactCard) AddUrls(urls []string) {
	for _, url := range urls {
		Contact.PullServers = append(Contact.PullServers, ServerFromUrl(url))
	}
}

func (contact *ContactCard) Serialize() ([]byte, error) {
	out, err := proto.Marshal(contact)
	if err != nil {
		return nil, err
	}
	return out, nil
}

func (contact *ContactCard) Compress() ([]byte, error) {
	out, err := contact.Serialize()
	if err != nil {
		return nil, err
	}
	var b bytes.Buffer
	gz := gzip.NewWriter(&b)
	if _, err := gz.Write(out); err != nil {
		log.Fatal(err)
	}
	if err := gz.Close(); err != nil {
		log.Fatal(err)
	}
	fmt.Println(b.Bytes())
	return b.Bytes(), nil
}

func (contact *ContactCard) WritePng(filename string) {
	out, err := proto.Marshal(contact)
	if err != nil {
		println(err)
	}
	size := int(math.Sqrt(float64(len(out))/3)) + 1
	println(size)

	// Create a colored i	mage of the given width and height.
	img := image.NewNRGBA(image.Rect(0, 0, size, size))

	for y := 0; y < size; y++ {
		for x := 0; x < size*3; x = x + 3 {
			p1 := uint8(out[x+y])
			p2 := uint8(out[x+y+1])
			p3 := uint8(out[x+y+2])
			img.Set(x/3, y, color.NRGBA{
				R: p1,
				G: p2,
				B: p3,
				A: 255,
			})
		}
	}

	f, err := os.Create(filename)
	if err != nil {
		log.Fatal(err)
	}

	if err := png.Encode(f, img); err != nil {
		f.Close()
		log.Fatal(err)
	}

	if err := f.Close(); err != nil {
		log.Fatal(err)
	}

}

func (Contact *ContactCard) WriteQr(filename string) {
	//jsonContact, _ := json.Marshal(Contact)
	jsonContact, _ := Contact.Compress()
	qwriter := qrcode.NewQRCodeWriter()
	code, err := qwriter.Encode(string(jsonContact), gozxing.BarcodeFormat_QR_CODE, 512, 512, nil)
	if err != nil {
		println(err.Error())
	}
	file, _ := os.Create(filename)
	defer file.Close()

	// *BitMatrix implements the image.Image interface,
	// so it is able to be passed to png.Encode directly.
	_ = png.Encode(file, code)

}

func ReadQr(Filename string) ContactCard {
	var contact ContactCard
	// open and decode image file
	file, _ := os.Open("qrcode.jpg")
	img, _, _ := image.Decode(file)

	// prepare BinaryBitmap
	bmp, _ := gozxing.NewBinaryBitmapFromImage(img)

	// decode image
	qrReader := qrcode.NewQRCodeReader()
	result, _ := qrReader.Decode(bmp, nil)

	fmt.Println(result)
	return contact
}