From 5b727a103ecc810e09921c6f2b12dea4044b14a3 Mon Sep 17 00:00:00 2001
From: Daniel <790119+DanTheMan827@users.noreply.github.com>
Date: Thu, 2 Apr 2026 16:23:49 -0500
Subject: [PATCH] feat(downloads): allow writing multiple artists to metadata

This will write each artist separately to the metadata rather than as a single concatenated string.  This allows for better library searching if the player supports it.

If multiple artists are written to an m4a file, iTunes will only show the first artist.
---
 index.html           | 14 ++++++++++++++
 js/ModernSettings.ts |  4 ++++
 js/metadata.js       | 18 ++++++++++++++----
 js/settings.js       |  9 +++++++++
 js/taglib.types.ts   |  3 ++-
 js/taglib.worker.ts  | 14 +++++++++++---
 js/utils.js          | 14 ++++++++++++--
 7 files changed, 66 insertions(+), 10 deletions(-)

diff --git a/index.html b/index.html
index f08edb7..776d6f4 100644
--- a/index.html
+++ b/index.html
@@ -4885,6 +4885,20 @@
                                     </label>
                                 </div>
                             </div>
+                            <div class="settings-group">
+                                <div class="setting-item">
+                                    <div class="info">
+                                        <span class="label">Write Artists Separately</span>
+                                        <span class="description"
+                                            >Write artists separately to metadata. Requires player support.</span
+                                        >
+                                    </div>
+                                    <label class="toggle-switch">
+                                        <input type="checkbox" id="write-artists-separately-toggle" />
+                                        <span class="slider"></span>
+                                    </label>
+                                </div>
+                            </div>
                             <div class="settings-group">
                                 <div class="setting-item">
                                     <div class="info">
diff --git a/js/ModernSettings.ts b/js/ModernSettings.ts
index de90cdc..c114181 100644
--- a/js/ModernSettings.ts
+++ b/js/ModernSettings.ts
@@ -261,6 +261,7 @@ export const modernSettings = new ModernSettings()
             transformer: String,
         },
     })
+    .addProperty('writeArtistsSeparately', false)
     .finalize() as ModernSettings & {
     /** The last used directory handle for bulk downloads */
     bulkDownloadFolder: FileSystemDirectoryHandle | null;
@@ -286,4 +287,7 @@ export const modernSettings = new ModernSettings()
 
     /** Filename template for downloads */
     filenameTemplate: string;
+
+    /** Whether to write multiple artists to downloaded files */
+    writeArtistsSeparately: boolean;
 };
diff --git a/js/metadata.js b/js/metadata.js
index 57fe1c8..b826ffd 100644
--- a/js/metadata.js
+++ b/js/metadata.js
@@ -1,7 +1,15 @@
-import { getCoverBlob, getTrackTitle, getFullArtistString, getMimeType, getTrackCoverId } from './utils.js';
+import {
+    getCoverBlob,
+    getTrackTitle,
+    getFullArtistString,
+    getMimeType,
+    getTrackCoverId,
+    getFullArtistArray,
+} from './utils.js';
 import { addMetadataWithTagLib, getMetadataWithTagLib } from './taglib.ts';
 import { LyricsManager } from './lyrics.js';
 import { Mp4Stik } from './taglib.types.ts';
+import { modernSettings } from './ModernSettings.js';
 
 /**
  * @typedef {import('./container-classes.ts').Track} Track
@@ -35,13 +43,15 @@ export async function addMetadataToAudio(audioBlob, track, api, _quality, prefet
     /**
      * @type {TagLibMetadata}
      */
-    const data = {};
+    const data = {
+        writeArtistsSeparately: modernSettings.writeArtistsSeparately,
+    };
 
     try {
         data.title = getTrackTitle(track);
-        data.artist = getFullArtistString(track);
+        data.artist = getFullArtistArray(track);
         data.albumTitle = track.album?.title;
-        data.albumArtist = track.album?.artist?.name || track.artist?.name;
+        data.albumArtist = track.album?.artist?.name || getFullArtistString(track) || '';
         data.trackNumber = track.trackNumber;
         data.discNumber = track.volumeNumber ?? track.discNumber;
         data.totalTracks = track.album?.numberOfTracksOnDisc ?? track.album?.numberOfTracks;
diff --git a/js/settings.js b/js/settings.js
index faa1df0..19951e6 100644
--- a/js/settings.js
+++ b/js/settings.js
@@ -4568,6 +4568,15 @@ export async function initializeSettings(scrobbler, player, api, ui) {
         });
     }
 
+    // Write multiple artists toggle
+    const writeArtistsSeparatelyToggle = document.getElementById('write-artists-separately-toggle');
+    if (writeArtistsSeparatelyToggle) {
+        writeArtistsSeparatelyToggle.checked = modernSettings.writeArtistsSeparately;
+        writeArtistsSeparatelyToggle.addEventListener('change', (e) => {
+            modernSettings.writeArtistsSeparately = e.target.checked;
+        });
+    }
+
     // Download Lyrics Toggle
     const downloadLyricsToggle = document.getElementById('download-lyrics-toggle');
     if (downloadLyricsToggle) {
diff --git a/js/taglib.types.ts b/js/taglib.types.ts
index 187d29b..45b3b72 100644
--- a/js/taglib.types.ts
+++ b/js/taglib.types.ts
@@ -16,7 +16,8 @@ export interface TagLibWorkerResponse<T> {
 
 export interface TagLibMetadata {
     title?: string;
-    artist?: string;
+    artist?: string | string[];
+    writeArtistsSeparately?: boolean;
     albumTitle?: string;
     albumArtist?: string;
     trackNumber?: number;
diff --git a/js/taglib.worker.ts b/js/taglib.worker.ts
index fb91b10..c06c495 100644
--- a/js/taglib.worker.ts
+++ b/js/taglib.worker.ts
@@ -29,8 +29,8 @@ import { FileSystemFileHandleStream } from '!/@dantheman827/taglib-ts/src/toolki
 import { FlacFile } from '!/@dantheman827/taglib-ts/src/flac/flacFile.js';
 import { MpegFile } from '!/@dantheman827/taglib-ts/src/mpeg/mpegFile.js';
 import { Mp4File } from '!/@dantheman827/taglib-ts/src/mp4/mp4File.js';
-import { OggFile } from '!/@dantheman827/taglib-ts/src/ogg/oggFile.js';
 import { OggVorbisFile } from '!/@dantheman827/taglib-ts/src/ogg/vorbis/vorbisFile.js';
+import { WavFile } from '!/@dantheman827/taglib-ts/src/riff/wav/wavFile';
 
 export const isWorker = typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope;
 
@@ -41,6 +41,7 @@ export async function addMetadataToAudio(message: _AddMetadataMessage): Promise<
         filename,
         title,
         artist,
+        writeArtistsSeparately = false,
         albumTitle,
         albumArtist,
         trackNumber,
@@ -74,17 +75,24 @@ export async function addMetadataToAudio(message: _AddMetadataMessage): Promise<
     }
 
     const underlying = ref.file();
+    const isFlac = underlying instanceof FlacFile;
     const isMp4 = underlying instanceof Mp4File;
     const isMpeg = underlying instanceof MpegFile;
+    const isOgg = underlying instanceof OggVorbisFile;
+    const isWav = underlying instanceof WavFile;
+
     const needsCombinedTrackDisc = isMp4 || isMpeg;
 
+    const artistArray = Array.isArray(artist) ? artist : artist ? [artist] : [];
+    const supportsMultiValuedArtist = writeArtistsSeparately && (isFlac || isOgg || isMp4);
+
     doTimed('Tagging file', () => {
         const props = ref.properties();
 
         if (title) props.replace('TITLE', [title]);
-        if (artist) props.replace('ARTIST', [artist]);
+        if (artistArray.length) props.replace('ARTIST', supportsMultiValuedArtist ? artistArray : [artistArray.join('; ')]);
         if (albumTitle) props.replace('ALBUM', [albumTitle]);
-        if (albumArtist || artist) props.replace('ALBUMARTIST', [albumArtist || artist!]);
+        if (albumArtist || artistArray.length) props.replace('ALBUMARTIST', albumArtist ? [albumArtist] : [artistArray.join('; ')]);
 
         if (trackNumber) {
             const trackStr =
diff --git a/js/utils.js b/js/utils.js
index 6c78b17..bd4be2e 100644
--- a/js/utils.js
+++ b/js/utils.js
@@ -616,10 +616,10 @@ export const getShareUrl = (path) => {
 };
 
 /**
- * Builds a full artist string by combining the track's listed artists
+ * Builds a full artist array by combining the track's listed artists
  * with any featured artists parsed from the title (feat./with).
  */
-export function getFullArtistString(track) {
+export function getFullArtistArray(track) {
     const knownArtists =
         Array.isArray(track.artists) && track.artists.length > 0
             ? track.artists.map((a) => (typeof a === 'string' ? a : a.name) || '').filter(Boolean)
@@ -646,6 +646,16 @@ export function getFullArtistString(track) {
         }
     }
 
+    return knownArtists;
+}
+
+/**
+ * Builds a full artist string by combining the track's listed artists
+ * with any featured artists parsed from the title (feat./with).
+ */
+export function getFullArtistString(track) {
+    const knownArtists = getFullArtistArray(track);
+
     return knownArtists.join('; ') || null;
 }