Switch to decimals in protocol code

protocol/decode.go

@@ -1,16 +1,10 @@
 package protocol
 
 import (
-	"errors"
 	"fmt"
 	"sort"
 )
 
-// default errors
-var (
-	ErrInvalidFrame = errors.New("invalid frame")
-)
-
 // Decoder represents protocol decode.
 type Decoder struct {
 	buffer   []byte
@@ -43,16 +37,16 @@ func NewDecoderSize(size int) *Decoder {
 // DecodeChunk takes a single chunk of data and decodes it.
 func (d *Decoder) DecodeChunk(data string) error {
 	if data == "" || len(data) < 4 {
-		return ErrInvalidFrame
+		return fmt.Errorf("invalid frame: \"%s\"", data)
 	}
 
 	var (
 		offset, total int
 		payload       []byte
 	)
-	_, err := fmt.Sscanf(data, "%x/%x|%s", &offset, &total, &payload)
+	_, err := fmt.Sscanf(data, "%d/%d|%s", &offset, &total, &payload)
 	if err != nil {
-		return fmt.Errorf("invalid frame: %v", err)
+		return fmt.Errorf("invalid frame: %v (%s)", err, data)
 	}
 
 	// allocate enough memory at first total read

protocol/encode.go

@@ -33,7 +33,7 @@ func (e *Encoder) EncodeReader(r io.Reader) ([]string, error) {
 // futher converted to QR code frames.
 func (e *Encoder) Encode(str string) ([]string, error) {
 	if len(str) < e.chunkLen {
-		return []string{str}, nil
+		return []string{e.frame(0, len(str), str)}, nil
 	}
 
 	numChunks := len(str)/e.chunkLen + 1
@@ -54,5 +54,5 @@ func (e *Encoder) Encode(str string) ([]string, error) {
 }
 
 func (e *Encoder) frame(count, total int, str string) string {
-	return fmt.Sprintf("%x/%x|%s", count, total, str)
+	return fmt.Sprintf("%d/%d|%s", count, total, str)
 }