v5.5

backend/metadata.go

@@ -0,0 +1,113 @@
+package backend
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+
+	"github.com/go-flac/flacpicture"
+	"github.com/go-flac/flacvorbis"
+	"github.com/go-flac/go-flac"
+)
+
+type Metadata struct {
+	Title       string
+	Artist      string
+	Album       string
+	Date        string
+	TrackNumber int
+	DiscNumber  int
+	ISRC        string
+}
+
+func EmbedMetadata(filepath string, metadata Metadata, coverPath string) error {
+	f, err := flac.ParseFile(filepath)
+	if err != nil {
+		return fmt.Errorf("failed to parse FLAC file: %w", err)
+	}
+
+	var cmtIdx = -1
+	for idx, block := range f.Meta {
+		if block.Type == flac.VorbisComment {
+			cmtIdx = idx
+			break
+		}
+	}
+
+	cmt := flacvorbis.New()
+
+	if metadata.Title != "" {
+		_ = cmt.Add(flacvorbis.FIELD_TITLE, metadata.Title)
+	}
+	if metadata.Artist != "" {
+		_ = cmt.Add(flacvorbis.FIELD_ARTIST, metadata.Artist)
+	}
+	if metadata.Album != "" {
+		_ = cmt.Add(flacvorbis.FIELD_ALBUM, metadata.Album)
+	}
+	if metadata.Date != "" {
+		_ = cmt.Add(flacvorbis.FIELD_DATE, metadata.Date)
+	}
+	if metadata.TrackNumber > 0 {
+		_ = cmt.Add(flacvorbis.FIELD_TRACKNUMBER, strconv.Itoa(metadata.TrackNumber))
+	}
+	if metadata.DiscNumber > 0 {
+		_ = cmt.Add("DISCNUMBER", strconv.Itoa(metadata.DiscNumber))
+	}
+	if metadata.ISRC != "" {
+		_ = cmt.Add(flacvorbis.FIELD_ISRC, metadata.ISRC)
+	}
+
+	cmtBlock := cmt.Marshal()
+	if cmtIdx < 0 {
+		f.Meta = append(f.Meta, &cmtBlock)
+	} else {
+		f.Meta[cmtIdx] = &cmtBlock
+	}
+
+	if coverPath != "" && fileExists(coverPath) {
+		if err := embedCoverArt(f, coverPath); err != nil {
+			fmt.Printf("Warning: Failed to embed cover art: %v\n", err)
+		}
+	}
+
+	if err := f.Save(filepath); err != nil {
+		return fmt.Errorf("failed to save FLAC file: %w", err)
+	}
+
+	return nil
+}
+
+func embedCoverArt(f *flac.File, coverPath string) error {
+	imgData, err := os.ReadFile(coverPath)
+	if err != nil {
+		return fmt.Errorf("failed to read cover image: %w", err)
+	}
+
+	picture, err := flacpicture.NewFromImageData(
+		flacpicture.PictureTypeFrontCover,
+		"Cover",
+		imgData,
+		"image/jpeg",
+	)
+	if err != nil {
+		return fmt.Errorf("failed to create picture block: %w", err)
+	}
+
+	pictureBlock := picture.Marshal()
+
+	for i := len(f.Meta) - 1; i >= 0; i-- {
+		if f.Meta[i].Type == flac.Picture {
+			f.Meta = append(f.Meta[:i], f.Meta[i+1:]...)
+		}
+	}
+
+	f.Meta = append(f.Meta, &pictureBlock)
+
+	return nil
+}
+
+func fileExists(path string) bool {
+	_, err := os.Stat(path)
+	return err == nil
+}