Show toast when download is skipped due to duplicate

Backend: set skipped:true on job when track already exists on disk.
Album downloads report "X geladen, Y bereits vorhanden" in the message.
Frontend: pollJob shows "⏭ bereits auf dem Server" instead of "✅ gespeichert"
when the job has skipped:true.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/novasonic-server.js

@@ -245,11 +245,11 @@ async function downloadTrack({ jobId, artist, albumArtist, title, album, year, t
 async function downloadAlbumTracks({ jobId, artist, albumTitle, tracks, artworkUrl }) {
   const total = tracks.length;
   log(jobId, `📀 Album "${albumTitle}" — ${total} Tracks`);
-  let done = 0;
+  let done = 0, skipped = 0;
 
   for (const track of tracks) {
     try {
-      await downloadTrack({
+      const result = await downloadTrack({
         jobId,
         artist:      track.artistName  || artist,  // track artist (may include feat.)
         albumArtist: artist,                        // always the main artist → consistent grouping
@@ -265,12 +265,13 @@ async function downloadAlbumTracks({ jobId, artist, albumTitle, tracks, artworkU
         artworkUrl:  artworkUrl || track.artworkUrl100,
         outputDir:   CONFIG.musicPath,
       });
-      done++;
-      updateJob(jobId, { progress: Math.round((done / total) * 90) });
+      if (result?.skipped) skipped++; else done++;
+      updateJob(jobId, { progress: Math.round(((done + skipped) / total) * 90) });
     } catch (e) {
       log(jobId, `⚠️  Fehler bei "${track.trackName || track.title}": ${e.message}`);
     }
   }
+  return { done, skipped };
 }
 
 // Search iTunes for album tracks by artist + album name (fallback when no collectionId)
@@ -350,8 +351,12 @@ app.post('/api/download', async (req, res) => {
     updateJob(jobId, { status: 'running', progress: 5, message: 'Gestartet…' });
     try {
       if (type === 'track') {
-        await downloadTrack({ jobId, artist, title, album, artworkUrl });
-        updateJob(jobId, { status: 'done', progress: 100, message: 'Fertig!' });
+        const result = await downloadTrack({ jobId, artist, title, album, artworkUrl });
+        if (result?.skipped) {
+          updateJob(jobId, { status: 'done', progress: 100, message: 'Bereits vorhanden – übersprungen', skipped: true });
+        } else {
+          updateJob(jobId, { status: 'done', progress: 100, message: 'Fertig!' });
+        }
 
       } else if (type === 'album') {
         let tracks = [];
@@ -366,8 +371,15 @@ app.post('/api/download', async (req, res) => {
         if (!tracks.length) {
           throw new Error(`Keine einzelnen Tracks für "${album || title}" gefunden. Bitte über iTunes Global-Suche herunterladen.`);
         }
-        await downloadAlbumTracks({ jobId, artist, albumTitle: album || title, tracks, artworkUrl });
-        updateJob(jobId, { status: 'done', progress: 100, message: `Album "${album || title}" fertig!` });
+        const { done: dlDone, skipped: dlSkipped } = await downloadAlbumTracks({ jobId, artist, albumTitle: album || title, tracks, artworkUrl });
+        const allSkipped = dlSkipped === tracks.length;
+        const someSkipped = dlSkipped > 0 && !allSkipped;
+        const msg = allSkipped
+          ? `Album bereits vorhanden – alle ${dlSkipped} Tracks übersprungen`
+          : someSkipped
+            ? `Album fertig! (${dlDone} geladen, ${dlSkipped} bereits vorhanden)`
+            : `Album "${album || title}" fertig!`;
+        updateJob(jobId, { status: 'done', progress: 100, message: msg, skipped: allSkipped });
 
       } else if (type === 'artist') {
         log(jobId, `🎤 Künstler-Download: ${artist}`);

src/ui.js

@@ -312,7 +312,10 @@ async function pollJob(jobId) {
     const d = await res.json();
     updateJob(jobId, d.status, d.message, d.progress);
     if(d.status!=='done' && d.status!=='error') setTimeout(() => pollJob(jobId), 1500);
-    else if(d.status==='done') toast(`✅ ${S.jobs[jobId]?.title||'Track'} gespeichert!`);
+    else if(d.status==='done') {
+      const title = S.jobs[jobId]?.title || 'Track';
+      toast(d.skipped ? `⏭ "${title}" bereits auf dem Server` : `✅ ${title} gespeichert!`);
+    }
   } catch { updateJob(jobId, 'error', 'Status-Abfrage fehlgeschlagen'); }
 }