Feat: a bit of progress with r1

pngmeta/altwriter.go

@@ -24,39 +24,32 @@ func WriteToPng(metadata *models.CharCardSpec, sourcePath, outfile string) error
 	if err != nil {
 		return err
 	}
-
 	jsonData, err := json.Marshal(metadata)
 	if err != nil {
 		return err
 	}
-
 	base64Data := base64.StdEncoding.EncodeToString(jsonData)
 	embedData := PngEmbed{
 		Key:   "elefant", // Replace with appropriate key constant
 		Value: base64Data,
 	}
-
 	var outputBuffer bytes.Buffer
 	if _, err := outputBuffer.Write([]byte(pngHeader)); err != nil {
 		return err
 	}
-
 	chunks, iend, err := processChunks(pngData[8:])
 	if err != nil {
 		return err
 	}
-
 	for _, chunk := range chunks {
 		outputBuffer.Write(chunk)
 	}
-
 	newChunk, err := createTextChunk(embedData)
 	if err != nil {
 		return err
 	}
 	outputBuffer.Write(newChunk)
 	outputBuffer.Write(iend)
-
 	return os.WriteFile(outfile, outputBuffer.Bytes(), 0666)
 }
 
@@ -67,7 +60,6 @@ func processChunks(data []byte) ([][]byte, []byte, error) {
 		iendChunk []byte
 		reader    = bytes.NewReader(data)
 	)
-
 	for {
 		var chunkLength uint32
 		if err := binary.Read(reader, binary.BigEndian, &chunkLength); err != nil {
@@ -76,22 +68,18 @@ func processChunks(data []byte) ([][]byte, []byte, error) {
 			}
 			return nil, nil, fmt.Errorf("error reading chunk length: %w", err)
 		}
-
 		chunkType := make([]byte, 4)
 		if _, err := reader.Read(chunkType); err != nil {
 			return nil, nil, fmt.Errorf("error reading chunk type: %w", err)
 		}
-
 		chunkData := make([]byte, chunkLength)
 		if _, err := reader.Read(chunkData); err != nil {
 			return nil, nil, fmt.Errorf("error reading chunk data: %w", err)
 		}
-
 		crc := make([]byte, 4)
 		if _, err := reader.Read(crc); err != nil {
 			return nil, nil, fmt.Errorf("error reading CRC: %w", err)
 		}
-
 		fullChunk := bytes.NewBuffer(nil)
 		if err := binary.Write(fullChunk, binary.BigEndian, chunkLength); err != nil {
 			return nil, nil, fmt.Errorf("error writing chunk length: %w", err)
@@ -105,7 +93,6 @@ func processChunks(data []byte) ([][]byte, []byte, error) {
 		if _, err := fullChunk.Write(crc); err != nil {
 			return nil, nil, fmt.Errorf("error writing CRC: %w", err)
 		}
-
 		switch string(chunkType) {
 		case "IEND":
 			iendChunk = fullChunk.Bytes()
@@ -116,7 +103,6 @@ func processChunks(data []byte) ([][]byte, []byte, error) {
 			chunks = append(chunks, fullChunk.Bytes())
 		}
 	}
-
 	return nil, nil, errors.New("IEND chunk not found")
 }
 
@@ -126,12 +112,10 @@ func createTextChunk(embed PngEmbed) ([]byte, error) {
 	content.WriteString(embed.Key)
 	content.WriteByte(0) // Null separator
 	content.WriteString(embed.Value)
-
 	data := content.Bytes()
 	crc := crc32.NewIEEE()
 	crc.Write([]byte(textChunkType))
 	crc.Write(data)
-
 	chunk := bytes.NewBuffer(nil)
 	if err := binary.Write(chunk, binary.BigEndian, uint32(len(data))); err != nil {
 		return nil, fmt.Errorf("error writing chunk length: %w", err)
@@ -145,6 +129,5 @@ func createTextChunk(embed PngEmbed) ([]byte, error) {
 	if err := binary.Write(chunk, binary.BigEndian, crc.Sum32()); err != nil {
 		return nil, fmt.Errorf("error writing CRC: %w", err)
 	}
-
 	return chunk.Bytes(), nil
 }