.redownlaod with suffix, isrc variable

app.go

@@ -159,6 +159,7 @@ type DownloadRequest struct {
 	SpotifyDiscNumber    int    `json:"spotify_disc_number,omitempty"`
 	SpotifyTotalTracks   int    `json:"spotify_total_tracks,omitempty"`
 	SpotifyTotalDiscs    int    `json:"spotify_total_discs,omitempty"`
+	ISRC                 string `json:"isrc,omitempty"`
 	Copyright            string `json:"copyright,omitempty"`
 	Publisher            string `json:"publisher,omitempty"`
 	Composer             string `json:"composer,omitempty"`
@@ -363,6 +364,9 @@ func (a *App) DownloadTrack(req DownloadRequest) (DownloadResponse, error) {
 	if req.FilenameFormat == "" {
 		req.FilenameFormat = "title-artist"
 	}
+	if req.ISRC == "" && strings.Contains(req.FilenameFormat, "{isrc}") && req.SpotifyID != "" {
+		req.ISRC = backend.ResolveTrackISRC(req.SpotifyID)
+	}
 
 	itemID := req.ItemID
 	if itemID == "" {
@@ -449,9 +453,10 @@ func (a *App) DownloadTrack(req DownloadRequest) (DownloadResponse, error) {
 	}
 
 	if req.TrackName != "" && req.ArtistName != "" {
-		expectedFilename := backend.BuildExpectedFilename(req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.SpotifyDiscNumber, req.UseAlbumTrackNumber)
+		expectedFilename := backend.BuildExpectedFilename(req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.SpotifyDiscNumber, req.UseAlbumTrackNumber, req.ISRC)
 		expectedPath := filepath.Join(req.OutputDir, expectedFilename)
 
+		if !backend.GetRedownloadWithSuffixSetting() {
 			if fileInfo, err := os.Stat(expectedPath); err == nil && fileInfo.Size() > 100*1024 {
 
 				backend.SkipDownloadItem(itemID, expectedPath)
@@ -464,6 +469,7 @@ func (a *App) DownloadTrack(req DownloadRequest) (DownloadResponse, error) {
 				}, nil
 			}
 		}
+	}
 
 	lyricsChan := make(chan string, 1)
 	isrcChan := make(chan string, 1)
@@ -506,32 +512,35 @@ func (a *App) DownloadTrack(req DownloadRequest) (DownloadResponse, error) {
 
 		downloader := backend.NewAmazonDownloader()
 		if req.ServiceURL != "" {
-			filename, err = downloader.DownloadByURL(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.CoverURL, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.EmbedMaxQualityCover, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+			filename, err = downloader.DownloadByURL(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.CoverURL, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.EmbedMaxQualityCover, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 		} else {
-			filename, err = downloader.DownloadBySpotifyID(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.CoverURL, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.EmbedMaxQualityCover, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+			filename, err = downloader.DownloadBySpotifyID(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.PlaylistName, req.PlaylistOwner, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.CoverURL, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.EmbedMaxQualityCover, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 		}
 
 	case "tidal":
 		if req.ApiURL == "" || req.ApiURL == "auto" {
 			downloader := backend.NewTidalDownloader("")
 			if req.ServiceURL != "" {
-				filename, err = downloader.DownloadByURLWithFallback(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+				filename, err = downloader.DownloadByURLWithFallback(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 			} else {
-				filename, err = downloader.Download(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+				filename, err = downloader.Download(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 			}
 		} else {
 			downloader := backend.NewTidalDownloader(req.ApiURL)
 			if req.ServiceURL != "" {
-				filename, err = downloader.DownloadByURL(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+				filename, err = downloader.DownloadByURL(req.ServiceURL, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 			} else {
-				filename, err = downloader.Download(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
+				filename, err = downloader.Download(req.SpotifyID, req.OutputDir, req.AudioFormat, req.FilenameFormat, req.TrackNumber, req.Position, req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, req.UseAlbumTrackNumber, req.CoverURL, req.EmbedMaxQualityCover, req.SpotifyTrackNumber, req.SpotifyDiscNumber, req.SpotifyTotalTracks, req.SpotifyTotalDiscs, req.Copyright, req.Publisher, req.Composer, metadataSeparator, req.ISRC, spotifyURL, req.AllowFallback, req.UseFirstArtistOnly, req.UseSingleGenre, req.EmbedGenre)
 			}
 		}
 
 	case "qobuz":
 
+		isrc := strings.TrimSpace(req.ISRC)
+		if isrc == "" {
 			fmt.Println("Waiting for ISRC (Qobuz dependency)...")
-		isrc := <-isrcChan
+			isrc = <-isrcChan
+		}
 		downloader := backend.NewQobuzDownloader()
 		quality := req.AudioFormat
 		if quality == "" {
@@ -957,6 +966,7 @@ type LyricsDownloadRequest struct {
 	AlbumName           string `json:"album_name"`
 	AlbumArtist         string `json:"album_artist"`
 	ReleaseDate         string `json:"release_date"`
+	ISRC                string `json:"isrc,omitempty"`
 	OutputDir           string `json:"output_dir"`
 	FilenameFormat      string `json:"filename_format"`
 	TrackNumber         bool   `json:"track_number"`
@@ -981,6 +991,7 @@ func (a *App) DownloadLyrics(req LyricsDownloadRequest) (backend.LyricsDownloadR
 		AlbumName:           req.AlbumName,
 		AlbumArtist:         req.AlbumArtist,
 		ReleaseDate:         req.ReleaseDate,
+		ISRC:                req.ISRC,
 		OutputDir:           req.OutputDir,
 		FilenameFormat:      req.FilenameFormat,
 		TrackNumber:         req.TrackNumber,
@@ -1404,6 +1415,7 @@ type CheckFileExistenceRequest struct {
 	AlbumName           string `json:"album_name,omitempty"`
 	AlbumArtist         string `json:"album_artist,omitempty"`
 	ReleaseDate         string `json:"release_date,omitempty"`
+	ISRC                string `json:"isrc,omitempty"`
 	TrackNumber         int    `json:"track_number,omitempty"`
 	DiscNumber          int    `json:"disc_number,omitempty"`
 	Position            int    `json:"position,omitempty"`
@@ -1433,6 +1445,7 @@ func (a *App) CheckFilesExistence(outputDir string, rootDir string, tracks []Che
 	}
 
 	defaultFilenameFormat := "title-artist"
+	redownloadWithSuffix := backend.GetRedownloadWithSuffixSetting()
 
 	type result struct {
 		index  int
@@ -1483,6 +1496,10 @@ func (a *App) CheckFilesExistence(outputDir string, rootDir string, tracks []Che
 			if filenameFormat == "" {
 				filenameFormat = defaultFilenameFormat
 			}
+			isrc := strings.TrimSpace(t.ISRC)
+			if isrc == "" && strings.Contains(filenameFormat, "{isrc}") && t.SpotifyID != "" {
+				isrc = backend.ResolveTrackISRC(t.SpotifyID)
+			}
 
 			trackNumber := t.Position
 			if t.UseAlbumTrackNumber && t.TrackNumber > 0 {
@@ -1507,6 +1524,7 @@ func (a *App) CheckFilesExistence(outputDir string, rootDir string, tracks []Che
 				trackNumber,
 				t.DiscNumber,
 				t.UseAlbumTrackNumber,
+				isrc,
 			)
 
 			expectedFilename := strings.TrimSuffix(expectedFilenameBase, ".flac") + fileExt
@@ -1517,7 +1535,10 @@ func (a *App) CheckFilesExistence(outputDir string, rootDir string, tracks []Che
 			}
 
 			expectedPath := filepath.Join(targetDir, expectedFilename)
-
+			if redownloadWithSuffix {
+				expectedPath, _ = backend.ResolveOutputPathForDownload(expectedPath, true)
+				res.FilePath = filepath.Base(expectedPath)
+			} else {
 				if fileInfo, err := os.Stat(expectedPath); err == nil && fileInfo.Size() > 100*1024 {
 					res.Exists = true
 					res.FilePath = expectedPath
@@ -1525,6 +1546,7 @@ func (a *App) CheckFilesExistence(outputDir string, rootDir string, tracks []Che
 
 					res.FilePath = expectedFilename
 				}
+			}
 
 			resultsChan <- result{index: idx, result: res}
 		}(i, track)
@@ -1573,6 +1595,10 @@ func (a *App) SkipDownloadItem(itemID, filePath string) {
 	backend.SkipDownloadItem(itemID, filePath)
 }
 
+func (a *App) GetTrackISRC(spotifyTrackID string) string {
+	return backend.ResolveTrackISRC(spotifyTrackID)
+}
+
 func (a *App) GetPreviewURL(trackID string) (string, error) {
 	return backend.GetPreviewURL(trackID)
 }

backend/amazon.go

@@ -204,7 +204,7 @@ func (a *AmazonDownloader) DownloadFromService(amazonURL, outputDir, quality str
 	return a.DownloadFromAfkarXYZ(amazonURL, outputDir, quality)
 }
 
-func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL string, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, embedMaxQualityCover bool, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL string, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
+func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL string, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, embedMaxQualityCover bool, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL string, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
 
 	if outputDir != "." {
 		if err := os.MkdirAll(outputDir, 0755); err != nil {
@@ -219,14 +219,16 @@ func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filename
 			filenameArtist = GetFirstArtist(spotifyArtistName)
 			filenameAlbumArtist = GetFirstArtist(spotifyAlbumArtist)
 		}
-		expectedFilename := BuildExpectedFilename(spotifyTrackName, filenameArtist, spotifyAlbumName, filenameAlbumArtist, spotifyReleaseDate, filenameFormat, playlistName, playlistOwner, includeTrackNumber, position, spotifyDiscNumber, false)
+		expectedFilename := BuildExpectedFilename(spotifyTrackName, filenameArtist, spotifyAlbumName, filenameAlbumArtist, spotifyReleaseDate, filenameFormat, playlistName, playlistOwner, includeTrackNumber, position, spotifyDiscNumber, false, isrcOverride)
 		expectedPath := filepath.Join(outputDir, expectedFilename)
 
+		if !GetRedownloadWithSuffixSetting() {
 			if fileInfo, err := os.Stat(expectedPath); err == nil && fileInfo.Size() > 0 {
 				fmt.Printf("File already exists: %s (%.2f MB)\n", expectedPath, float64(fileInfo.Size())/(1024*1024))
 				return "EXISTS:" + expectedPath, nil
 			}
 		}
+	}
 
 	type mbResult struct {
 		ISRC     string
@@ -271,11 +273,13 @@ func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filename
 		return "", err
 	}
 
-	var isrc string
+	isrc := strings.TrimSpace(isrcOverride)
 	var mbMeta Metadata
 	if spotifyURL != "" {
 		result := <-metaChan
+		if isrc == "" {
 			isrc = result.ISRC
+		}
 		mbMeta = result.Metadata
 	}
 
@@ -309,6 +313,7 @@ func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filename
 			newFilename = strings.ReplaceAll(newFilename, "{album_artist}", safeAlbumArtist)
 			newFilename = strings.ReplaceAll(newFilename, "{year}", year)
 			newFilename = strings.ReplaceAll(newFilename, "{date}", SanitizeFilename(spotifyReleaseDate))
+			newFilename = strings.ReplaceAll(newFilename, "{isrc}", SanitizeOptionalFilename(isrc))
 
 			if spotifyDiscNumber > 0 {
 				newFilename = strings.ReplaceAll(newFilename, "{disc}", fmt.Sprintf("%d", spotifyDiscNumber))
@@ -346,6 +351,9 @@ func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filename
 		}
 		newFilename = newFilename + ext
 		newFilePath := filepath.Join(outputDir, newFilename)
+		if GetRedownloadWithSuffixSetting() {
+			newFilePath, _ = ResolveOutputPathForDownload(newFilePath, true)
+		}
 
 		if err := os.Rename(filePath, newFilePath); err != nil {
 			fmt.Printf("Warning: Failed to rename file: %v\n", err)
@@ -420,7 +428,7 @@ func (a *AmazonDownloader) DownloadByURL(amazonURL, outputDir, quality, filename
 	return filePath, nil
 }
 
-func (a *AmazonDownloader) DownloadBySpotifyID(spotifyTrackID, outputDir, quality, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL string, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, embedMaxQualityCover bool, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL string,
+func (a *AmazonDownloader) DownloadBySpotifyID(spotifyTrackID, outputDir, quality, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL string, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, embedMaxQualityCover bool, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL string,
 	useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool,
 ) (string, error) {
 
@@ -429,5 +437,5 @@ func (a *AmazonDownloader) DownloadBySpotifyID(spotifyTrackID, outputDir, qualit
 		return "", err
 	}
 
-	return a.DownloadByURL(amazonURL, outputDir, quality, filenameFormat, playlistName, playlistOwner, includeTrackNumber, position, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks, embedMaxQualityCover, spotifyTotalDiscs, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL, useFirstArtistOnly, useSingleGenre, embedGenre)
+	return a.DownloadByURL(amazonURL, outputDir, quality, filenameFormat, playlistName, playlistOwner, includeTrackNumber, position, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, spotifyCoverURL, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks, embedMaxQualityCover, spotifyTotalDiscs, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL, useFirstArtistOnly, useSingleGenre, embedGenre)
 }

backend/config.go

@@ -69,6 +69,16 @@ func GetSpotFetchAPISettings() (bool, string) {
 	return true, apiURL
 }
 
+func GetRedownloadWithSuffixSetting() bool {
+	settings, err := LoadConfigSettings()
+	if err != nil || settings == nil {
+		return false
+	}
+
+	enabled, _ := settings["redownloadWithSuffix"].(bool)
+	return enabled
+}
+
 func GetLinkResolverSetting() string {
 	settings, err := LoadConfigSettings()
 	if err != nil || settings == nil {

backend/filemanager.go

@@ -30,6 +30,7 @@ type AudioMetadata struct {
 	TrackNumber int    `json:"track_number"`
 	DiscNumber  int    `json:"disc_number"`
 	Year        string `json:"year"`
+	ISRC        string `json:"isrc"`
 }
 
 type RenamePreview struct {
@@ -175,6 +176,8 @@ func readFlacMetadata(filePath string) (*AudioMetadata, error) {
 					}
 				case "DATE", "YEAR":
 					metadata.Year = value
+				case "ISRC", "TSRC":
+					metadata.ISRC = value
 				}
 			}
 		}
@@ -221,6 +224,12 @@ func readMp3Metadata(filePath string) (*AudioMetadata, error) {
 		}
 	}
 
+	if frames := tag.GetFrames("TSRC"); len(frames) > 0 {
+		if textFrame, ok := frames[0].(id3v2.TextFrame); ok {
+			metadata.ISRC = textFrame.Text
+		}
+	}
+
 	return metadata, nil
 }
 
@@ -301,6 +310,8 @@ func readMetadataWithFFprobe(filePath string) (*AudioMetadata, error) {
 			if metadata.Year == "" || len(value) > len(metadata.Year) {
 				metadata.Year = value
 			}
+		case "isrc", "tsrc":
+			metadata.ISRC = value
 		}
 	}
 
@@ -333,6 +344,7 @@ func GenerateFilename(metadata *AudioMetadata, format string, ext string) string
 	result = strings.ReplaceAll(result, "{album_artist}", sanitizeFilenameForRename(metadata.AlbumArtist))
 	result = strings.ReplaceAll(result, "{year}", sanitizeFilenameForRename(year))
 	result = strings.ReplaceAll(result, "{date}", sanitizeFilenameForRename(metadata.Year))
+	result = strings.ReplaceAll(result, "{isrc}", sanitizeFilenameForRename(metadata.ISRC))
 
 	if metadata.TrackNumber > 0 {
 		result = strings.ReplaceAll(result, "{track}", fmt.Sprintf("%02d", metadata.TrackNumber))

backend/filename.go

@@ -2,6 +2,7 @@ package backend
 
 import (
 	"fmt"
+	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -9,12 +10,12 @@ import (
 	"unicode/utf8"
 )
 
-func BuildExpectedFilename(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position, discNumber int, useAlbumTrackNumber bool) string {
+func buildFormattedFilenameBase(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat, playlistName, playlistOwner, isrc string, includeTrackNumber bool, position, discNumber int, useAlbumTrackNumber bool) string {
-
 	safeTitle := SanitizeFilename(trackName)
 	safeArtist := SanitizeFilename(artistName)
 	safeAlbum := SanitizeFilename(albumName)
 	safeAlbumArtist := SanitizeFilename(albumArtist)
+	safeISRC := SanitizeOptionalFilename(isrc)
 
 	safePlaylist := SanitizeFilename(playlistName)
 	safeCreator := SanitizeFilename(playlistOwner)
@@ -36,6 +37,7 @@ func BuildExpectedFilename(trackName, artistName, albumName, albumArtist, releas
 		filename = strings.ReplaceAll(filename, "{date}", SanitizeFilename(releaseDate))
 		filename = strings.ReplaceAll(filename, "{playlist}", safePlaylist)
 		filename = strings.ReplaceAll(filename, "{creator}", safeCreator)
+		filename = strings.ReplaceAll(filename, "{isrc}", safeISRC)
 
 		if discNumber > 0 {
 			filename = strings.ReplaceAll(filename, "{disc}", fmt.Sprintf("%d", discNumber))
@@ -67,7 +69,47 @@ func BuildExpectedFilename(trackName, artistName, albumName, albumArtist, releas
 		}
 	}
 
-	return filename + ".flac"
+	return filename
+}
+
+func BuildExpectedFilename(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat, playlistName, playlistOwner string, includeTrackNumber bool, position, discNumber int, useAlbumTrackNumber bool, extra ...string) string {
+	isrc := ""
+	if len(extra) > 0 {
+		isrc = extra[0]
+	}
+
+	return buildFormattedFilenameBase(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat, playlistName, playlistOwner, isrc, includeTrackNumber, position, discNumber, useAlbumTrackNumber) + ".flac"
+}
+
+func ResolveOutputPathForDownload(path string, redownloadWithSuffix bool) (string, bool) {
+	if !redownloadWithSuffix {
+		if info, err := os.Stat(path); err == nil && info.Size() > 0 {
+			return path, true
+		}
+		return path, false
+	}
+
+	if info, err := os.Stat(path); err != nil || info.Size() == 0 {
+		return path, false
+	}
+
+	ext := filepath.Ext(path)
+	base := strings.TrimSuffix(path, ext)
+
+	for i := 1; ; i++ {
+		candidate := fmt.Sprintf("%s_%02d%s", base, i, ext)
+		if info, err := os.Stat(candidate); err != nil || info.Size() == 0 {
+			return candidate, false
+		}
+	}
+}
+
+func mustFileSize(path string) int64 {
+	info, err := os.Stat(path)
+	if err != nil {
+		return 0
+	}
+	return info.Size()
 }
 
 func SanitizeFilename(name string) string {
@@ -188,3 +230,10 @@ func sanitizeFolderName(name string) string { return SanitizeFilename(name) }
 func sanitizeFilename(name string) string {
 	return SanitizeFilename(name)
 }
+
+func SanitizeOptionalFilename(name string) string {
+	if strings.TrimSpace(name) == "" {
+		return ""
+	}
+	return SanitizeFilename(name)
+}

backend/isrc_helper.go

@@ -0,0 +1,22 @@
+package backend
+
+import "strings"
+
+func ResolveTrackISRC(spotifyTrackID string) string {
+	spotifyTrackID = strings.TrimSpace(spotifyTrackID)
+	if spotifyTrackID == "" {
+		return ""
+	}
+
+	if cachedISRC, err := GetCachedISRC(spotifyTrackID); err == nil && cachedISRC != "" {
+		return strings.ToUpper(strings.TrimSpace(cachedISRC))
+	}
+
+	client := NewSongLinkClient()
+	isrc, err := client.GetISRCDirect(spotifyTrackID)
+	if err != nil {
+		return ""
+	}
+
+	return strings.ToUpper(strings.TrimSpace(isrc))
+}

backend/lyrics.go

@@ -44,6 +44,7 @@ type LyricsDownloadRequest struct {
 	AlbumName           string `json:"album_name"`
 	AlbumArtist         string `json:"album_artist"`
 	ReleaseDate         string `json:"release_date"`
+	ISRC                string `json:"isrc"`
 	OutputDir           string `json:"output_dir"`
 	FilenameFormat      string `json:"filename_format"`
 	TrackNumber         bool   `json:"track_number"`
@@ -363,11 +364,12 @@ func msToLRCTimestamp(msStr string) string {
 	return fmt.Sprintf("[%02d:%02d.%02d]", minutes, seconds, centiseconds)
 }
 
-func buildLyricsFilename(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat string, includeTrackNumber bool, position, discNumber int) string {
+func buildLyricsFilename(trackName, artistName, albumName, albumArtist, releaseDate, filenameFormat, isrc string, includeTrackNumber bool, position, discNumber int) string {
 	safeTitle := sanitizeFilename(trackName)
 	safeArtist := sanitizeFilename(artistName)
 	safeAlbum := sanitizeFilename(albumName)
 	safeAlbumArtist := sanitizeFilename(albumArtist)
+	safeISRC := SanitizeOptionalFilename(isrc)
 
 	year := ""
 	if len(releaseDate) >= 4 {
@@ -384,6 +386,7 @@ func buildLyricsFilename(trackName, artistName, albumName, albumArtist, releaseD
 		filename = strings.ReplaceAll(filename, "{album_artist}", safeAlbumArtist)
 		filename = strings.ReplaceAll(filename, "{year}", year)
 		filename = strings.ReplaceAll(filename, "{date}", sanitizeFilename(releaseDate))
+		filename = strings.ReplaceAll(filename, "{isrc}", safeISRC)
 
 		if discNumber > 0 {
 			filename = strings.ReplaceAll(filename, "{disc}", fmt.Sprintf("%d", discNumber))
@@ -485,10 +488,15 @@ func (c *LyricsClient) DownloadLyrics(req LyricsDownloadRequest) (*LyricsDownloa
 	if filenameFormat == "" {
 		filenameFormat = "title-artist"
 	}
-	filename := buildLyricsFilename(req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, filenameFormat, req.TrackNumber, req.Position, req.DiscNumber)
+	resolvedISRC := strings.TrimSpace(req.ISRC)
+	if resolvedISRC == "" && strings.Contains(filenameFormat, "{isrc}") {
+		resolvedISRC = ResolveTrackISRC(req.SpotifyID)
+	}
+	filename := buildLyricsFilename(req.TrackName, req.ArtistName, req.AlbumName, req.AlbumArtist, req.ReleaseDate, filenameFormat, resolvedISRC, req.TrackNumber, req.Position, req.DiscNumber)
 	filePath := filepath.Join(outputDir, filename)
 
-	if fileInfo, err := os.Stat(filePath); err == nil && fileInfo.Size() > 0 {
+	filePath, alreadyExists := ResolveOutputPathForDownload(filePath, GetRedownloadWithSuffixSetting())
+	if alreadyExists {
 		return &LyricsDownloadResponse{
 			Success:       true,
 			Message:       "Lyrics file already exists",

backend/qobuz.go

@@ -326,8 +326,12 @@ func (q *QobuzDownloader) DownloadCoverArt(coverURL, filepath string) error {
 	return err
 }
 
-func buildQobuzFilename(title, artist, album, albumArtist, releaseDate string, trackNumber, discNumber int, format string, includeTrackNumber bool, position int, useAlbumTrackNumber bool) string {
+func buildQobuzFilename(title, artist, album, albumArtist, releaseDate string, trackNumber, discNumber int, format string, includeTrackNumber bool, position int, useAlbumTrackNumber bool, extra ...string) string {
 	var filename string
+	isrc := ""
+	if len(extra) > 0 {
+		isrc = SanitizeOptionalFilename(extra[0])
+	}
 
 	numberToUse := position
 	if useAlbumTrackNumber && trackNumber > 0 {
@@ -347,6 +351,7 @@ func buildQobuzFilename(title, artist, album, albumArtist, releaseDate string, t
 		filename = strings.ReplaceAll(filename, "{album_artist}", albumArtist)
 		filename = strings.ReplaceAll(filename, "{year}", year)
 		filename = strings.ReplaceAll(filename, "{date}", SanitizeFilename(releaseDate))
+		filename = strings.ReplaceAll(filename, "{isrc}", isrc)
 
 		if discNumber > 0 {
 			filename = strings.ReplaceAll(filename, "{disc}", fmt.Sprintf("%d", discNumber))
@@ -467,11 +472,11 @@ func (q *QobuzDownloader) DownloadTrackWithISRC(isrc, outputDir, quality, filena
 	safeTitle := sanitizeFilename(trackTitle)
 	safeAlbum := sanitizeFilename(albumTitle)
 
-	filename := buildQobuzFilename(safeTitle, safeArtist, safeAlbum, safeAlbumArtist, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber)
+	filename := buildQobuzFilename(safeTitle, safeArtist, safeAlbum, safeAlbumArtist, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber, isrc)
 	filepath := filepath.Join(outputDir, filename)
-
+	filepath, alreadyExists := ResolveOutputPathForDownload(filepath, GetRedownloadWithSuffixSetting())
-	if fileInfo, err := os.Stat(filepath); err == nil && fileInfo.Size() > 0 {
+	if alreadyExists {
-		fmt.Printf("File already exists: %s (%.2f MB)\n", filepath, float64(fileInfo.Size())/(1024*1024))
+		fmt.Printf("File already exists: %s (%.2f MB)\n", filepath, float64(mustFileSize(filepath))/(1024*1024))
 		return "EXISTS:" + filepath, nil
 	}
 

backend/tidal.go

@@ -416,7 +416,7 @@ func (t *TidalDownloader) DownloadFromManifest(manifestB64, outputPath string) e
 	return nil
 }
 
-func (t *TidalDownloader) DownloadByURL(tidalURL, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
+func (t *TidalDownloader) DownloadByURL(tidalURL, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
 	if outputDir != "." {
 		if err := os.MkdirAll(outputDir, 0755); err != nil {
 			return "", fmt.Errorf("directory error: %w", err)
@@ -449,11 +449,12 @@ func (t *TidalDownloader) DownloadByURL(tidalURL, outputDir, quality, filenameFo
 	trackTitleForFile := sanitizeFilename(trackTitle)
 	albumTitleForFile := sanitizeFilename(albumTitle)
 
-	filename := buildTidalFilename(trackTitleForFile, artistNameForFile, albumTitleForFile, albumArtistForFile, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber)
+	filename := buildTidalFilename(trackTitleForFile, artistNameForFile, albumTitleForFile, albumArtistForFile, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber, isrcOverride)
 	outputFilename := filepath.Join(outputDir, filename)
 
-	if fileInfo, err := os.Stat(outputFilename); err == nil && fileInfo.Size() > 0 {
+	outputFilename, alreadyExists := ResolveOutputPathForDownload(outputFilename, GetRedownloadWithSuffixSetting())
-		fmt.Printf("File already exists: %s (%.2f MB)\n", outputFilename, float64(fileInfo.Size())/(1024*1024))
+	if alreadyExists {
+		fmt.Printf("File already exists: %s (%.2f MB)\n", outputFilename, float64(mustFileSize(outputFilename))/(1024*1024))
 		return "EXISTS:" + outputFilename, nil
 	}
 
@@ -511,11 +512,13 @@ func (t *TidalDownloader) DownloadByURL(tidalURL, outputDir, quality, filenameFo
 		return "", err
 	}
 
-	var isrc string
+	isrc := strings.TrimSpace(isrcOverride)
 	var mbMeta Metadata
 	if spotifyURL != "" {
 		result := <-metaChan
+		if isrc == "" {
 			isrc = result.ISRC
+		}
 		mbMeta = result.Metadata
 	}
 
@@ -572,7 +575,7 @@ func (t *TidalDownloader) DownloadByURL(tidalURL, outputDir, quality, filenameFo
 	return outputFilename, nil
 }
 
-func (t *TidalDownloader) DownloadByURLWithFallback(tidalURL, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
+func (t *TidalDownloader) DownloadByURLWithFallback(tidalURL, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
 	apis, err := t.GetAvailableAPIs()
 	if err != nil {
 		return "", fmt.Errorf("no APIs available for fallback: %w", err)
@@ -610,11 +613,12 @@ func (t *TidalDownloader) DownloadByURLWithFallback(tidalURL, outputDir, quality
 	trackTitleForFile := sanitizeFilename(trackTitle)
 	albumTitleForFile := sanitizeFilename(albumTitle)
 
-	filename := buildTidalFilename(trackTitleForFile, artistNameForFile, albumTitleForFile, albumArtistForFile, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber)
+	filename := buildTidalFilename(trackTitleForFile, artistNameForFile, albumTitleForFile, albumArtistForFile, spotifyReleaseDate, spotifyTrackNumber, spotifyDiscNumber, filenameFormat, includeTrackNumber, position, useAlbumTrackNumber, isrcOverride)
 	outputFilename := filepath.Join(outputDir, filename)
 
-	if fileInfo, err := os.Stat(outputFilename); err == nil && fileInfo.Size() > 0 {
+	outputFilename, alreadyExists := ResolveOutputPathForDownload(outputFilename, GetRedownloadWithSuffixSetting())
-		fmt.Printf("File already exists: %s (%.2f MB)\n", outputFilename, float64(fileInfo.Size())/(1024*1024))
+	if alreadyExists {
+		fmt.Printf("File already exists: %s (%.2f MB)\n", outputFilename, float64(mustFileSize(outputFilename))/(1024*1024))
 		return "EXISTS:" + outputFilename, nil
 	}
 
@@ -673,11 +677,13 @@ func (t *TidalDownloader) DownloadByURLWithFallback(tidalURL, outputDir, quality
 		return "", err
 	}
 
-	var isrc string
+	isrc := strings.TrimSpace(isrcOverride)
 	var mbMeta Metadata
 	if spotifyURL != "" {
 		result := <-metaChan
+		if isrc == "" {
 			isrc = result.ISRC
+		}
 		mbMeta = result.Metadata
 	}
 
@@ -734,14 +740,14 @@ func (t *TidalDownloader) DownloadByURLWithFallback(tidalURL, outputDir, quality
 	return outputFilename, nil
 }
 
-func (t *TidalDownloader) Download(spotifyTrackID, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
+func (t *TidalDownloader) Download(spotifyTrackID, outputDir, quality, filenameFormat string, includeTrackNumber bool, position int, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate string, useAlbumTrackNumber bool, spotifyCoverURL string, embedMaxQualityCover bool, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks int, spotifyTotalDiscs int, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL string, allowFallback bool, useFirstArtistOnly bool, useSingleGenre bool, embedGenre bool) (string, error) {
 
 	tidalURL, err := t.GetTidalURLFromSpotify(spotifyTrackID)
 	if err != nil {
 		return "", fmt.Errorf("songlink couldn't find Tidal URL: %w", err)
 	}
 
-	return t.DownloadByURLWithFallback(tidalURL, outputDir, quality, filenameFormat, includeTrackNumber, position, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, useAlbumTrackNumber, spotifyCoverURL, embedMaxQualityCover, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks, spotifyTotalDiscs, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, spotifyURL, allowFallback, useFirstArtistOnly, useSingleGenre, embedGenre)
+	return t.DownloadByURLWithFallback(tidalURL, outputDir, quality, filenameFormat, includeTrackNumber, position, spotifyTrackName, spotifyArtistName, spotifyAlbumName, spotifyAlbumArtist, spotifyReleaseDate, useAlbumTrackNumber, spotifyCoverURL, embedMaxQualityCover, spotifyTrackNumber, spotifyDiscNumber, spotifyTotalTracks, spotifyTotalDiscs, spotifyCopyright, spotifyPublisher, spotifyComposer, metadataSeparator, isrcOverride, spotifyURL, allowFallback, useFirstArtistOnly, useSingleGenre, embedGenre)
 }
 
 type SegmentTemplate struct {
@@ -981,8 +987,12 @@ func getDownloadURLRotated(apis []string, trackID int64, quality string) (string
 	return "", "", fmt.Errorf("all %d APIs failed. Last error: %v", len(apis), lastError)
 }
 
-func buildTidalFilename(title, artist, album, albumArtist, releaseDate string, trackNumber, discNumber int, format string, includeTrackNumber bool, position int, useAlbumTrackNumber bool) string {
+func buildTidalFilename(title, artist, album, albumArtist, releaseDate string, trackNumber, discNumber int, format string, includeTrackNumber bool, position int, useAlbumTrackNumber bool, extra ...string) string {
 	var filename string
+	isrc := ""
+	if len(extra) > 0 {
+		isrc = SanitizeOptionalFilename(extra[0])
+	}
 
 	numberToUse := position
 	if useAlbumTrackNumber && trackNumber > 0 {
@@ -1002,6 +1012,7 @@ func buildTidalFilename(title, artist, album, albumArtist, releaseDate string, t
 		filename = strings.ReplaceAll(filename, "{album_artist}", albumArtist)
 		filename = strings.ReplaceAll(filename, "{year}", year)
 		filename = strings.ReplaceAll(filename, "{date}", SanitizeFilename(releaseDate))
+		filename = strings.ReplaceAll(filename, "{isrc}", isrc)
 
 		if discNumber > 0 {
 			filename = strings.ReplaceAll(filename, "{disc}", fmt.Sprintf("%d", discNumber))

frontend/src/components/FileManagerPage.tsx

@@ -36,6 +36,7 @@ interface FileMetadata {
     track_number: number;
     disc_number: number;
     year: string;
+    isrc?: string;
 }
 type TabType = "track" | "lyric" | "cover";
 const FORMAT_PRESETS: Record<string, {
@@ -549,7 +550,7 @@ export function FileManagerPage() {
             <Info className="h-3.5 w-3.5 text-muted-foreground cursor-help"/>
           </TooltipTrigger>
           <TooltipContent side="right">
-            <p className="text-xs whitespace-nowrap">Variables: {"{title}"}, {"{artist}"}, {"{album}"}, {"{album_artist}"}, {"{track}"}, {"{disc}"}, {"{year}"}, {"{date}"}</p>
+            <p className="text-xs whitespace-nowrap">Variables: {"{title}"}, {"{artist}"}, {"{album}"}, {"{album_artist}"}, {"{track}"}, {"{disc}"}, {"{year}"}, {"{date}"}, {"{isrc}"}</p>
           </TooltipContent>
         </Tooltip>
       </div>
@@ -571,7 +572,7 @@ export function FileManagerPage() {
         </Tooltip>
       </div>
       <p className="text-xs text-muted-foreground">
-        Preview: <span className="font-mono">{renameFormat.replace(/\{title\}/g, "All The Stars").replace(/\{artist\}/g, "Kendrick Lamar, SZA").replace(/\{album\}/g, "Black Panther").replace(/\{album_artist\}/g, "Kendrick Lamar").replace(/\{track\}/g, "01").replace(/\{disc\}/g, "1").replace(/\{year\}/g, "2018").replace(/\{date\}/g, "2018-02-09")}.flac</span>
+        Preview: <span className="font-mono">{renameFormat.replace(/\{title\}/g, "All The Stars").replace(/\{artist\}/g, "Kendrick Lamar, SZA").replace(/\{album\}/g, "Black Panther").replace(/\{album_artist\}/g, "Kendrick Lamar").replace(/\{track\}/g, "01").replace(/\{disc\}/g, "1").replace(/\{year\}/g, "2018").replace(/\{date\}/g, "2018-02-09").replace(/\{isrc\}/g, "USUM71801234")}.flac</span>
       </p>
     </div>)}
 
@@ -660,6 +661,7 @@ export function FileManagerPage() {
           <div className="grid grid-cols-[100px_1fr] gap-2 text-sm"><span className="text-muted-foreground">Track</span><span>{metadataInfo.track_number || "-"}</span></div>
           <div className="grid grid-cols-[100px_1fr] gap-2 text-sm"><span className="text-muted-foreground">Disc</span><span>{metadataInfo.disc_number || "-"}</span></div>
           <div className="grid grid-cols-[100px_1fr] gap-2 text-sm"><span className="text-muted-foreground">Year</span><span>{metadataInfo.year ? metadataInfo.year.substring(0, 4) : "-"}</span></div>
+          <div className="grid grid-cols-[100px_1fr] gap-2 text-sm"><span className="text-muted-foreground">ISRC</span><span>{metadataInfo.isrc || "-"}</span></div>
         </div>) : (<div className="text-center py-4 text-muted-foreground">No metadata available</div>)}
         <DialogFooter><Button onClick={() => setShowMetadata(false)}>Close</Button></DialogFooter>
       </DialogContent>

frontend/src/components/SettingsPage.tsx

@@ -568,7 +568,8 @@ export function SettingsPage({ onUnsavedChangesChange, onResetRequest, }: Settin
                     .replace(/\{track\}/g, "01")
                     .replace(/\{disc\}/g, "1")
                     .replace(/\{year\}/g, "2018")
-                    .replace(/\{date\}/g, "2018-02-09")}
+                    .replace(/\{date\}/g, "2018-02-09")
+                    .replace(/\{isrc\}/g, "USUM71801234")}
                       /
                     </span>
                   </p>)}
@@ -614,6 +615,16 @@ export function SettingsPage({ onUnsavedChangesChange, onResetRequest, }: Settin
                 </Label>
               </div>
 
+              <div className="flex items-center gap-3">
+                <Switch id="redownload-with-suffix" checked={tempSettings.redownloadWithSuffix} onCheckedChange={(checked) => setTempSettings((prev) => ({
+                ...prev,
+                redownloadWithSuffix: checked,
+            }))}/>
+                <Label htmlFor="redownload-with-suffix" className="text-sm cursor-pointer font-normal">
+                  Redownload With Suffix
+                </Label>
+              </div>
+
 
             </div>
 
@@ -686,7 +697,8 @@ export function SettingsPage({ onUnsavedChangesChange, onResetRequest, }: Settin
                     .replace(/\{track\}/g, "01")
                     .replace(/\{disc\}/g, "1")
                     .replace(/\{year\}/g, "2018")
-                    .replace(/\{date\}/g, "2018-02-09")}
+                    .replace(/\{date\}/g, "2018-02-09")
+                    .replace(/\{isrc\}/g, "USUM71801234")}
                     .flac
                   </span>
                 </p>)}

frontend/src/hooks/useDownload.ts

@@ -12,6 +12,7 @@ interface CheckFileExistenceRequest {
     album_name?: string;
     album_artist?: string;
     release_date?: string;
+    isrc?: string;
     track_number?: number;
     disc_number?: number;
     position?: number;
@@ -31,6 +32,24 @@ interface FileExistenceResult {
 const CheckFilesExistence = (outputDir: string, rootDir: string, tracks: CheckFileExistenceRequest[]): Promise<FileExistenceResult[]> => (window as any)["go"]["main"]["App"]["CheckFilesExistence"](outputDir, rootDir, tracks);
 const SkipDownloadItem = (itemID: string, filePath: string): Promise<void> => (window as any)["go"]["main"]["App"]["SkipDownloadItem"](itemID, filePath);
 const CreateM3U8File = (playlistName: string, outputDir: string, filePaths: string[]): Promise<void> => (window as any)["go"]["main"]["App"]["CreateM3U8File"](playlistName, outputDir, filePaths);
+const GetTrackISRC = (spotifyId: string): Promise<string> => (window as any)["go"]["main"]["App"]["GetTrackISRC"](spotifyId);
+
+async function resolveTemplateISRC(settings: { folderTemplate?: string; filenameTemplate?: string }, spotifyId?: string): Promise<string> {
+    if (!spotifyId) {
+        return "";
+    }
+    const folderTemplate = settings.folderTemplate || "";
+    const filenameTemplate = settings.filenameTemplate || "";
+    if (!folderTemplate.includes("{isrc}") && !filenameTemplate.includes("{isrc}")) {
+        return "";
+    }
+    try {
+        return await GetTrackISRC(spotifyId);
+    }
+    catch {
+        return "";
+    }
+}
 export function useDownload(region: string) {
     const [downloadProgress, setDownloadProgress] = useState<number>(0);
     const [isDownloading, setIsDownloading] = useState(false);
@@ -81,11 +100,13 @@ export function useDownload(region: string) {
         const displayAlbumArtist = settings.useFirstArtistOnly && albumArtist
             ? getFirstArtist(albumArtist)
             : albumArtist;
+        const resolvedTemplateISRC = await resolveTemplateISRC(settings, spotifyId || id);
         const templateData: TemplateData = {
             artist: displayArtist?.replace(/\//g, placeholder),
             album: albumName?.replace(/\//g, placeholder),
             album_artist: displayAlbumArtist?.replace(/\//g, placeholder) || displayArtist?.replace(/\//g, placeholder),
             title: trackName?.replace(/\//g, placeholder),
+            isrc: resolvedTemplateISRC?.replace(/\//g, placeholder),
             track: trackNumberForTemplate,
             year: yearValue,
             date: releaseDate,
@@ -117,6 +138,7 @@ export function useDownload(region: string) {
                     album_name: albumName,
                     album_artist: displayAlbumArtist,
                     release_date: finalReleaseDate || releaseDate,
+                    isrc: resolvedTemplateISRC || undefined,
                     track_number: finalTrackNumber || spotifyTrackNumber || 0,
                     disc_number: spotifyDiscNumber || 0,
                     position: trackNumberForTemplate,
@@ -193,6 +215,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_first_artist_only: settings.useFirstArtistOnly,
@@ -240,6 +263,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_single_genre: settings.useSingleGenre,
@@ -286,6 +310,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_single_genre: settings.useSingleGenre,
@@ -350,6 +375,7 @@ export function useDownload(region: string) {
             spotify_disc_number: spotifyDiscNumber,
             spotify_total_tracks: spotifyTotalTracks,
             spotify_total_discs: spotifyTotalDiscs,
+            isrc: resolvedTemplateISRC || undefined,
             copyright: copyright,
             publisher: publisher,
             use_single_genre: settings.useSingleGenre,
@@ -395,11 +421,13 @@ export function useDownload(region: string) {
         const displayAlbumArtist = settings.useFirstArtistOnly && albumArtist
             ? getFirstArtist(albumArtist)
             : albumArtist;
+        const resolvedTemplateISRC = await resolveTemplateISRC(settings, spotifyId);
         const templateData: TemplateData = {
             artist: displayArtist?.replace(/\//g, placeholder),
             album: albumName?.replace(/\//g, placeholder),
             album_artist: displayAlbumArtist?.replace(/\//g, placeholder) || displayArtist?.replace(/\//g, placeholder),
             title: trackName?.replace(/\//g, placeholder),
+            isrc: resolvedTemplateISRC?.replace(/\//g, placeholder),
             track: trackNumberForTemplate,
             year: yearValue,
             date: releaseDate,
@@ -468,6 +496,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_first_artist_only: settings.useFirstArtistOnly,
@@ -515,6 +544,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_first_artist_only: settings.useFirstArtistOnly,
@@ -563,6 +593,7 @@ export function useDownload(region: string) {
                             spotify_disc_number: spotifyDiscNumber,
                             spotify_total_tracks: spotifyTotalTracks,
                             spotify_total_discs: spotifyTotalDiscs,
+                            isrc: resolvedTemplateISRC || undefined,
                             copyright: copyright,
                             publisher: publisher,
                             use_first_artist_only: settings.useFirstArtistOnly,
@@ -624,6 +655,7 @@ export function useDownload(region: string) {
             spotify_disc_number: spotifyDiscNumber,
             spotify_total_tracks: spotifyTotalTracks,
             spotify_total_discs: spotifyTotalDiscs,
+            isrc: resolvedTemplateISRC || undefined,
             copyright: copyright,
             publisher: publisher,
             use_first_artist_only: settings.useFirstArtistOnly,

frontend/src/hooks/useLyrics.ts

@@ -5,6 +5,24 @@ import { toastWithSound as toast } from "@/lib/toast-with-sound";
 import { joinPath, sanitizePath, getFirstArtist } from "@/lib/utils";
 import { logger } from "@/lib/logger";
 import type { TrackMetadata } from "@/types/api";
+const GetTrackISRC = (spotifyId: string): Promise<string> => (window as any)["go"]["main"]["App"]["GetTrackISRC"](spotifyId);
+
+async function resolveTemplateISRC(settings: { folderTemplate?: string; filenameTemplate?: string }, spotifyId?: string): Promise<string> {
+    if (!spotifyId) {
+        return "";
+    }
+    const folderTemplate = settings.folderTemplate || "";
+    const filenameTemplate = settings.filenameTemplate || "";
+    if (!folderTemplate.includes("{isrc}") && !filenameTemplate.includes("{isrc}")) {
+        return "";
+    }
+    try {
+        return await GetTrackISRC(spotifyId);
+    }
+    catch {
+        return "";
+    }
+}
 export function useLyrics() {
     const [downloadingLyricsTrack, setDownloadingLyricsTrack] = useState<string | null>(null);
     const [downloadedLyrics, setDownloadedLyrics] = useState<Set<string>>(new Set());
@@ -28,11 +46,13 @@ export function useLyrics() {
             const yearValue = releaseDate?.substring(0, 4);
             const displayArtist = settings.useFirstArtistOnly && artistName ? getFirstArtist(artistName) : artistName;
             const displayAlbumArtist = settings.useFirstArtistOnly && albumArtist ? getFirstArtist(albumArtist) : albumArtist;
+            const resolvedTemplateISRC = await resolveTemplateISRC(settings, spotifyId);
             const templateData: TemplateData = {
                 artist: displayArtist?.replace(/\//g, placeholder),
                 album: albumName?.replace(/\//g, placeholder),
                 album_artist: displayAlbumArtist?.replace(/\//g, placeholder) || displayArtist?.replace(/\//g, placeholder),
                 title: trackName?.replace(/\//g, placeholder),
+                isrc: resolvedTemplateISRC?.replace(/\//g, placeholder),
                 track: position,
                 year: yearValue,
                 date: releaseDate,
@@ -61,6 +81,7 @@ export function useLyrics() {
                 album_name: albumName,
                 album_artist: displayAlbumArtist,
                 release_date: releaseDate,
+                isrc: resolvedTemplateISRC || undefined,
                 output_dir: outputDir,
                 filename_format: settings.filenameTemplate || "{title}",
                 track_number: settings.trackNumber,
@@ -129,11 +150,13 @@ export function useLyrics() {
                 const yearValue = track.release_date?.substring(0, 4);
                 const displayArtist = settings.useFirstArtistOnly && track.artists ? getFirstArtist(track.artists) : track.artists;
                 const displayAlbumArtist = settings.useFirstArtistOnly && track.album_artist ? getFirstArtist(track.album_artist) : track.album_artist;
+                const resolvedTemplateISRC = await resolveTemplateISRC(settings, id);
                 const templateData: TemplateData = {
                     artist: displayArtist?.replace(/\//g, placeholder),
                     album: track.album_name?.replace(/\//g, placeholder),
                     album_artist: displayAlbumArtist?.replace(/\//g, placeholder) || displayArtist?.replace(/\//g, placeholder),
                     title: track.name?.replace(/\//g, placeholder),
+                    isrc: resolvedTemplateISRC?.replace(/\//g, placeholder),
                     track: trackPosition,
                     year: yearValue,
                     date: track.release_date,
@@ -161,6 +184,7 @@ export function useLyrics() {
                     album_name: track.album_name,
                     album_artist: displayAlbumArtist,
                     release_date: track.release_date,
+                    isrc: resolvedTemplateISRC || undefined,
                     output_dir: outputDir,
                     filename_format: settings.filenameTemplate || "{title}",
                     track_number: settings.trackNumber,

frontend/src/lib/settings.ts

@@ -36,6 +36,7 @@ export interface Settings {
     useFirstArtistOnly: boolean;
     useSingleGenre: boolean;
     embedGenre: boolean;
+    redownloadWithSuffix: boolean;
     separator: "comma" | "semicolon";
 }
 export const FOLDER_PRESETS: Record<FolderPreset, {
@@ -85,6 +86,7 @@ export const TEMPLATE_VARIABLES = [
     { key: "{disc}", description: "Disc number", example: "1" },
     { key: "{year}", description: "Release year", example: "2014" },
     { key: "{date}", description: "Release date (YYYY-MM-DD)", example: "2014-10-27" },
+    { key: "{isrc}", description: "Track ISRC", example: "USUM71412345" },
 ];
 function detectOS(): "Windows" | "linux/MacOS" {
     const platform = window.navigator.platform.toLowerCase();
@@ -124,6 +126,7 @@ export const DEFAULT_SETTINGS: Settings = {
     useFirstArtistOnly: false,
     useSingleGenre: false,
     embedGenre: true,
+    redownloadWithSuffix: false,
     separator: "semicolon"
 };
 export const FONT_OPTIONS: {
@@ -243,6 +246,9 @@ function getSettingsFromLocalStorage(): Settings {
             if (!('separator' in parsed)) {
                 parsed.separator = "semicolon";
             }
+            if (!('redownloadWithSuffix' in parsed)) {
+                parsed.redownloadWithSuffix = false;
+            }
             return { ...DEFAULT_SETTINGS, ...parsed };
         }
     }
@@ -346,6 +352,9 @@ export async function loadSettings(): Promise<Settings> {
             if (!('separator' in parsed)) {
                 parsed.separator = "semicolon";
             }
+            if (!('redownloadWithSuffix' in parsed)) {
+                parsed.redownloadWithSuffix = false;
+            }
             cachedSettings = { ...DEFAULT_SETTINGS, ...parsed };
             return cachedSettings!;
         }
@@ -368,6 +377,7 @@ export interface TemplateData {
     album?: string;
     album_artist?: string;
     title?: string;
+    isrc?: string;
     track?: number;
     disc?: number;
     year?: string;
@@ -382,6 +392,7 @@ export function parseTemplate(template: string, data: TemplateData): string {
     result = result.replace(/\{artist\}/g, data.artist || "Unknown Artist");
     result = result.replace(/\{album\}/g, data.album || "Unknown Album");
     result = result.replace(/\{album_artist\}/g, data.album_artist || data.artist || "Unknown Artist");
+    result = result.replace(/\{isrc\}/g, data.isrc || "");
     result = result.replace(/\{track\}/g, data.track ? String(data.track).padStart(2, "0") : "00");
     result = result.replace(/\{disc\}/g, data.disc ? String(data.disc) : "1");
     result = result.replace(/\{year\}/g, data.year || "0000");

frontend/src/types/api.ts

@@ -23,6 +23,7 @@ export interface TrackMetadata {
     artist_id?: string;
     artist_url?: string;
     artists_data?: ArtistSimple[];
+    isrc?: string;
     copyright?: string;
     publisher?: string;
     plays?: string;
@@ -134,6 +135,7 @@ export interface DownloadRequest {
     spotify_disc_number?: number;
     spotify_total_tracks?: number;
     spotify_total_discs?: number;
+    isrc?: string;
     copyright?: string;
     publisher?: string;
     spotify_url?: string;
@@ -190,6 +192,7 @@ export interface LyricsDownloadRequest {
     album_name?: string;
     album_artist?: string;
     release_date?: string;
+    isrc?: string;
     output_dir?: string;
     filename_format?: string;
     track_number?: boolean;
@@ -278,4 +281,5 @@ export interface AudioMetadata {
     track_number: number;
     disc_number: number;
     year: string;
+    isrc?: string;
 }