invitation process upgrade

invitationinitpayload.go

@@ -0,0 +1,80 @@
+package meowlib
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"os"
+
+	"github.com/makiuchi-d/gozxing"
+	"github.com/makiuchi-d/gozxing/qrcode"
+	"google.golang.org/protobuf/proto"
+
+	"image/png"
+)
+
+func (p *InvitationInitPayload) Serialize() ([]byte, error) {
+	return proto.Marshal(p)
+}
+
+func (p *InvitationInitPayload) Compress() ([]byte, error) {
+	out, err := p.Serialize()
+	if err != nil {
+		return nil, err
+	}
+	var b bytes.Buffer
+	gz, err := gzip.NewWriterLevel(&b, gzip.BestCompression)
+	if err != nil {
+		return nil, err
+	}
+	if _, err := gz.Write(out); err != nil {
+		return nil, err
+	}
+	if err := gz.Close(); err != nil {
+		return nil, err
+	}
+	return b.Bytes(), nil
+}
+
+func NewInvitationInitPayloadFromCompressed(compressed []byte) (*InvitationInitPayload, error) {
+	p := &InvitationInitPayload{}
+	reader := bytes.NewReader(compressed)
+	gzreader, err := gzip.NewReader(reader)
+	if err != nil {
+		return nil, err
+	}
+	output, err := io.ReadAll(gzreader)
+	if err != nil {
+		return nil, err
+	}
+	if err := proto.Unmarshal(output, p); err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+func (p *InvitationInitPayload) WriteCompressed(filename string) error {
+	out, err := p.Compress()
+	if err != nil {
+		return err
+	}
+	return os.WriteFile(filename, out, 0600)
+}
+
+func (p *InvitationInitPayload) WriteQr(filename string) error {
+	data, err := p.Compress()
+	if err != nil {
+		return err
+	}
+	qwriter := qrcode.NewQRCodeWriter()
+	code, err := qwriter.Encode(string(data), gozxing.BarcodeFormat_QR_CODE, 512, 512, nil)
+	if err != nil {
+		return err
+	}
+	file, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	return png.Encode(file, code)
+}