Add 4 new cover/tracklist sources: MB back cover, iTunes, Last.fm, Discogs tracklist

cover_handler.py:
- _download_image(): shared helper replaces duplicated download logic
- download_back_cover(): fetches back cover from MusicBrainz CAA (/back endpoint),
  saves as back.jpg; skips if already present
- _itunes_cover_url() / download_itunes_cover(): iTunes Search API (no auth),
  requests 600x600 artwork; fallback after Discogs
- _lastfm_cover_url() / download_lastfm_cover(): Last.fm album.getinfo
  (LASTFM_API_KEY env var); last cover fallback, skips placeholder images
- resolve_cover(): extended with iTunes → Last.fm fallback chain

metadata_resolver.py:
- _discogs_get_tracklist(): fetches full Discogs release via REST API,
  parses tracklist[] including heading-based disc detection
- _lastfm_tracklist(): fetches Last.fm album.getinfo tracks (LASTFM_API_KEY)
- resolve(): uses Discogs tracklist → Last.fm tracklist as fallback when
  MusicBrainz returns no tracks; LASTFM_API_KEY added to env var block

music_enricher.py:
- process_album(): calls download_back_cover() after execute_album() when MBID known

New cover priority:  local → MusicBrainz front → Discogs → iTunes → Last.fm
New tracklist priority: local → YouTube → MusicBrainz → Discogs → Last.fm → OCR
Test suite: 29 → 33 tests (all pass)

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

cover_handler.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import io
+import os
 import sys
 import tempfile
 import time
@@ -108,21 +110,14 @@ def _mb_cover_url(release_mbid: str) -> Optional[str]:
     return None
 
 
-def download_cover(release_mbid: Optional[str], dest_dir: Path) -> Optional[Path]:
-    if not release_mbid or not HAS_REQUESTS:
-        return None
-    url = _mb_cover_url(release_mbid)
-    if not url:
-        return None
-    dest = dest_dir / "folder.jpg"
+def _download_image(url: str, dest: Path, label: str = "") -> Optional[Path]:
+    """Hilfsfunktion: URL herunterladen, PNG→JPEG konvertieren, als dest speichern."""
     try:
-        r = requests.get(url, timeout=15)
+        r = requests.get(url, timeout=15, headers={"User-Agent": "MusicMetadataEnricher/1.0"})
         if r.status_code != 200:
             return None
         ct = r.headers.get("content-type", "")
-        if "png" in ct and HAS_PIL:
-            # PNG → JPEG konvertieren
-            import io
+        if ("png" in ct or url.lower().endswith(".png")) and HAS_PIL:
             with Image.open(io.BytesIO(r.content)) as img:
                 buf = io.BytesIO()
                 img.convert("RGB").save(buf, format="JPEG", quality=92)
@@ -133,11 +128,38 @@ def download_cover(release_mbid: Optional[str], dest_dir: Path) -> Optional[Path
             return dest
         dest.unlink(missing_ok=True)
     except Exception as e:
-        print(f"  ⚠️ Cover-Download-Fehler: {e}", file=sys.stderr)
+        if label:
+            print(f"  ⚠️ {label}: {e}", file=sys.stderr)
         dest.unlink(missing_ok=True)
     return None
 
 
+def download_cover(release_mbid: Optional[str], dest_dir: Path) -> Optional[Path]:
+    if not release_mbid or not HAS_REQUESTS:
+        return None
+    url = _mb_cover_url(release_mbid)
+    if not url:
+        return None
+    return _download_image(url, dest_dir / "folder.jpg", "Cover-Download-Fehler")
+
+
+def download_back_cover(release_mbid: Optional[str], dest_dir: Path) -> Optional[Path]:
+    """Lädt das Back-Cover von MusicBrainz Cover Art Archive als back.jpg."""
+    if not release_mbid or not HAS_REQUESTS:
+        return None
+    dest = dest_dir / "back.jpg"
+    if dest.exists():
+        return dest  # bereits vorhanden
+    url = f"https://coverartarchive.org/release/{release_mbid}/back"
+    try:
+        r = requests.head(url, timeout=5, allow_redirects=True)
+        if r.status_code != 200:
+            return None
+    except Exception:
+        return None
+    return _download_image(url, dest, "Back-Cover-Fehler")
+
+
 def _load_cover_data(cover_path: Path) -> tuple[bytes, str]:
     """
     Liest Cover-Bilddaten und gibt (bytes, mime_type) zurück.
@@ -253,29 +275,71 @@ def download_discogs_cover(artist: Optional[str], album: Optional[str], dest_dir
     url = _discogs_cover_url(artist, album)
     if not url:
         return None
-    dest = dest_dir / "folder.jpg"
+    return _download_image(url, dest_dir / "folder.jpg", "Discogs-Cover-Fehler")
+
+
+def _itunes_cover_url(artist: Optional[str], album: Optional[str]) -> Optional[str]:
+    """Sucht auf iTunes nach artist+album, gibt 600x600-Artwork-URL zurück."""
+    if not HAS_REQUESTS or not (artist or album):
+        return None
+    term = f"{artist or ''} {album or ''}".strip()
     try:
-        r = requests.get(url, timeout=15, headers={"User-Agent": "MusicMetadataEnricher/1.0"})
+        r = requests.get(
+            "https://itunes.apple.com/search",
+            params={"term": term, "media": "music", "entity": "album", "limit": 5},
+            timeout=8,
+        )
         if r.status_code != 200:
             return None
-        ct = r.headers.get("content-type", "")
-        if ("png" in ct or url.lower().endswith(".png")) and HAS_PIL:
-            import io
-            with Image.open(io.BytesIO(r.content)) as img:
-                buf = io.BytesIO()
-                img.convert("RGB").save(buf, format="JPEG", quality=92)
-                dest.write_bytes(buf.getvalue())
-        else:
-            dest.write_bytes(r.content)
-        if _image_ok(dest):
-            return dest
-        dest.unlink(missing_ok=True)
+        for result in r.json().get("results", []):
+            url = result.get("artworkUrl100", "")
+            if url:
+                # Auf 600x600 hochskalieren
+                return url.replace("100x100bb", "600x600bb").replace("100x100", "600x600")
     except Exception as e:
-        print(f"  ⚠️ Discogs-Cover-Fehler: {e}", file=sys.stderr)
-        dest.unlink(missing_ok=True)
+        print(f"  ⚠️ iTunes-Suche: {e}", file=sys.stderr)
     return None
 
 
+def download_itunes_cover(artist: Optional[str], album: Optional[str], dest_dir: Path) -> Optional[Path]:
+    url = _itunes_cover_url(artist, album)
+    if not url:
+        return None
+    return _download_image(url, dest_dir / "folder.jpg", "iTunes-Cover-Fehler")
+
+
+def _lastfm_cover_url(artist: Optional[str], album: Optional[str]) -> Optional[str]:
+    """Last.fm album.getinfo → größtes verfügbares Artwork-URL."""
+    api_key = os.getenv("LASTFM_API_KEY", "")
+    if not HAS_REQUESTS or not api_key or not artist or not album:
+        return None
+    try:
+        r = requests.get(
+            "https://ws.audioscrobbler.com/2.0/",
+            params={"method": "album.getinfo", "api_key": api_key,
+                    "artist": artist, "album": album, "format": "json"},
+            timeout=8,
+        )
+        if r.status_code != 200:
+            return None
+        images = r.json().get("album", {}).get("image", [])
+        # Images sind aufsteigend nach Größe sortiert: small, medium, large, extralarge, mega
+        for img in reversed(images):
+            url = img.get("#text", "")
+            if url and "2a96cbd8b46e442fc41c2b86b821562f" not in url:  # Last.fm Platzhalter-Hash
+                return url
+    except Exception as e:
+        print(f"  ⚠️ Last.fm-Cover: {e}", file=sys.stderr)
+    return None
+
+
+def download_lastfm_cover(artist: Optional[str], album: Optional[str], dest_dir: Path) -> Optional[Path]:
+    url = _lastfm_cover_url(artist, album)
+    if not url:
+        return None
+    return _download_image(url, dest_dir / "folder.jpg", "Last.fm-Cover-Fehler")
+
+
 def resolve_cover(
     image_files: List[Path],
     release_mbid: Optional[str],
@@ -299,4 +363,14 @@ def resolve_cover(
         if downloaded:
             return downloaded, "discogs"
 
+    if artist or album:
+        downloaded = download_itunes_cover(artist, album, album_dir)
+        if downloaded:
+            return downloaded, "itunes"
+
+    if artist or album:
+        downloaded = download_lastfm_cover(artist, album, album_dir)
+        if downloaded:
+            return downloaded, "lastfm"
+
     return None, None

metadata_resolver.py

@@ -92,11 +92,12 @@ def normalize_genre(genre: Optional[str]) -> Optional[str]:
 
 _MB_RATE_LIMIT = 1.1   # seconds between MusicBrainz requests
 _last_mb_call = 0.0
-ACOUSTID_API_KEY  = os.getenv("ACOUSTID_API_KEY", "")
-ANTHROPIC_API_KEY = os.getenv("ANTHROPIC_API_KEY", "")
+ACOUSTID_API_KEY   = os.getenv("ACOUSTID_API_KEY", "")
+ANTHROPIC_API_KEY  = os.getenv("ANTHROPIC_API_KEY", "")
 OPENROUTER_API_KEY = os.getenv("OPENROUTER_API_KEY", "")
-DISCOGS_TOKEN     = os.getenv("DISCOGS_TOKEN", "")
-OLLAMA_HOST       = os.getenv("OLLAMA_HOST", "http://localhost:11434")
+DISCOGS_TOKEN      = os.getenv("DISCOGS_TOKEN", "")
+LASTFM_API_KEY     = os.getenv("LASTFM_API_KEY", "")
+OLLAMA_HOST        = os.getenv("OLLAMA_HOST", "http://localhost:11434")
 
 # qwen3:8b (5.2GB) reicht für einfache JSON-Metadaten-Ergänzung und lädt schnell (~10s)
 OLLAMA_RESOLVE_MODEL = os.getenv("OLLAMA_RESOLVE_MODEL", "qwen3:8b")
@@ -231,6 +232,78 @@ def _discogs_search(artist: Optional[str], album: Optional[str]) -> Optional[Dic
     return None
 
 
+def _discogs_get_tracklist(release_id) -> List[Dict]:
+    """Holt die vollständige Tracklist eines Discogs-Release via REST-API."""
+    try:
+        import requests as _req
+        token = DISCOGS_TOKEN
+        headers = {"User-Agent": "MusicMetadataEnricher/1.0"}
+        if token:
+            headers["Authorization"] = f"Discogs token={token}"
+        r = _req.get(f"https://api.discogs.com/releases/{release_id}",
+                     headers=headers, timeout=10)
+        if r.status_code != 200:
+            return []
+        tracklist = r.json().get("tracklist", [])
+        result = []
+        disc = 1
+        track_num = 0
+        for entry in tracklist:
+            if entry.get("type_") == "heading":
+                # Disc-Trennzeile ("CD 1", "Side A", …) — Disc hochzählen
+                disc += 1
+                track_num = 0
+                continue
+            pos = entry.get("position", "")
+            # Position kann "A1", "1", "1.2", "B3" sein
+            num_match = re.search(r"\d+", pos)
+            track_num = int(num_match.group()) if num_match else track_num + 1
+            result.append({
+                "disc": disc,
+                "number": track_num,
+                "title": entry.get("title", ""),
+                "artist": "",
+            })
+        return result
+    except Exception as e:
+        print(f"  ⚠️ Discogs-Tracklist-Fehler: {e}", file=sys.stderr)
+        return []
+
+
+def _lastfm_tracklist(artist: Optional[str], album: Optional[str]) -> List[Dict]:
+    """Holt die Tracklist von Last.fm album.getinfo (LASTFM_API_KEY erforderlich)."""
+    api_key = os.getenv("LASTFM_API_KEY", "")
+    if not api_key or not artist or not album:
+        return []
+    try:
+        import requests as _req
+        r = _req.get(
+            "https://ws.audioscrobbler.com/2.0/",
+            params={"method": "album.getinfo", "api_key": api_key,
+                    "artist": artist, "album": album, "format": "json"},
+            timeout=8,
+        )
+        if r.status_code != 200:
+            return []
+        tracks = r.json().get("album", {}).get("tracks", {}).get("track", [])
+        if isinstance(tracks, dict):  # Einzelner Track → Liste
+            tracks = [tracks]
+        result = []
+        for t in tracks:
+            attr = t.get("@attr", {})
+            num = int(attr.get("rank", 0))
+            result.append({
+                "disc": 1,
+                "number": num,
+                "title": t.get("name", ""),
+                "artist": t.get("artist", {}).get("name", "") if isinstance(t.get("artist"), dict) else "",
+            })
+        return result
+    except Exception as e:
+        print(f"  ⚠️ Last.fm-Tracklist-Fehler: {e}", file=sys.stderr)
+        return []
+
+
 # ---------------------------------------------------------------------------
 # Claude API reasoning (optional)
 # ---------------------------------------------------------------------------
@@ -485,6 +558,7 @@ def resolve(
                     })
 
     # Discogs fallback
+    discogs_release_id = None
     if use_api and HAS_DISCOGS and DISCOGS_TOKEN and not release_mbid:
         dg = _discogs_search(artist, album)
         if dg:
@@ -493,9 +567,23 @@ def resolve(
             year = year or dg.get("year")
             genre = genre or dg.get("genre")
             label = label or dg.get("label")
+            discogs_release_id = dg.get("id")
             confidence += 0.15
             sources.append("discogs")
 
+    # Tracklist-Fallbacks: Discogs → Last.fm (wenn MusicBrainz keine Tracks geliefert hat)
+    if use_api and not mb_tracks:
+        if discogs_release_id:
+            dg_tracks = _discogs_get_tracklist(discogs_release_id)
+            if dg_tracks:
+                mb_tracks = dg_tracks
+                sources.append("discogs-tracklist")
+        if not mb_tracks:
+            lfm_tracks = _lastfm_tracklist(artist, album)
+            if lfm_tracks:
+                mb_tracks = lfm_tracks
+                sources.append("lastfm-tracklist")
+
     # LLM-Reasoning für verbleibende Lücken:
     # Reihenfolge: Ollama lokal → OpenRouter (DeepSeek, günstig) → Claude API
     cl_albumartist: Optional[str] = None

music_enricher.py

@@ -26,7 +26,7 @@ from models import AlbumProposal
 from scanner import scan_album, collect_album_dirs
 from hint_extractor import extract_hints
 from metadata_resolver import resolve
-from cover_handler import resolve_cover
+from cover_handler import resolve_cover, download_back_cover
 from executor import execute_album, write_report
 
 
@@ -216,6 +216,12 @@ def process_album(
         for k, v in album_stats.items():
             stats[k] = stats.get(k, 0) + v
 
+        # Back-Cover von MusicBrainz holen (wenn MBID bekannt und noch kein back.jpg)
+        if proposal.mbid and not args.no_cover and not args.dry_run:
+            back = download_back_cover(proposal.mbid, album_dir)
+            if back:
+                print(f"  🖼️  Back-Cover heruntergeladen: {back.name}")
+
         # Jellyfin Playlist Generator aufrufen
         generator_path = _find_jellyfin_generator(album_dir, getattr(args, "playlist_generator", None))
         if generator_path:

test_suite_enricher.py

@@ -322,6 +322,74 @@ def test_normalize_cover_renames_front_jpg() -> str:
     return "Front.jpg → folder.jpg rename OK"
 
 
+# ---------------------------------------------------------------------------
+# New cover sources Tests
+# ---------------------------------------------------------------------------
+
+def test_itunes_cover_url_format() -> str:
+    from cover_handler import _itunes_cover_url
+    # Ohne echten Netzwerkaufruf: testen ob Funktion bei leeren Eingaben None zurückgibt
+    assert _itunes_cover_url(None, None) is None, "None inputs → None"
+    assert _itunes_cover_url("", "") is None, "empty inputs → None"
+    return "iTunes URL helper: None-Handling OK"
+
+
+def test_discogs_tracklist_format() -> str:
+    from metadata_resolver import _discogs_get_tracklist
+    # Simuliere API-Antwort-Parsing mit einem Testfall
+    import unittest.mock as mock
+    fake_response = {
+        "tracklist": [
+            {"position": "1", "type_": "track", "title": "Song A", "duration": "3:20"},
+            {"type_": "heading", "title": "CD 2"},
+            {"position": "1", "type_": "track", "title": "Song B", "duration": "4:00"},
+        ]
+    }
+    with mock.patch("requests.get") as mock_get:
+        mock_get.return_value.status_code = 200
+        mock_get.return_value.json.return_value = fake_response
+        tracks = _discogs_get_tracklist(12345)
+    assert len(tracks) == 2, f"expected 2 tracks, got {len(tracks)}"
+    assert tracks[0]["title"] == "Song A", f"track 0: {tracks[0]}"
+    assert tracks[1]["disc"] == 2, f"disc should be 2 after heading: {tracks[1]}"
+    return f"Discogs tracklist format OK: {len(tracks)} tracks"
+
+
+def test_lastfm_tracklist_format() -> str:
+    from metadata_resolver import _lastfm_tracklist
+    import unittest.mock as mock, os
+    fake_response = {
+        "album": {
+            "tracks": {
+                "track": [
+                    {"name": "Track One", "@attr": {"rank": "1"}, "artist": {"name": "Artist"}},
+                    {"name": "Track Two", "@attr": {"rank": "2"}, "artist": {"name": "Artist"}},
+                ]
+            }
+        }
+    }
+    with mock.patch.dict(os.environ, {"LASTFM_API_KEY": "testkey"}):
+        with mock.patch("requests.get") as mock_get:
+            mock_get.return_value.status_code = 200
+            mock_get.return_value.json.return_value = fake_response
+            tracks = _lastfm_tracklist("Artist", "Album")
+    assert len(tracks) == 2, f"expected 2 tracks, got {len(tracks)}"
+    assert tracks[0]["title"] == "Track One", f"track 0: {tracks[0]}"
+    assert tracks[0]["number"] == 1, f"rank/number: {tracks[0]}"
+    return f"Last.fm tracklist format OK: {len(tracks)} tracks"
+
+
+def test_back_cover_skips_if_exists() -> str:
+    from cover_handler import download_back_cover
+    with tempfile.TemporaryDirectory() as tmpdir:
+        root = Path(tmpdir)
+        back = root / "back.jpg"
+        back.write_bytes(b"\xff\xd8" + b"\x00" * 200)
+        result = download_back_cover("fake-mbid", root)
+        assert result == back, f"should return existing back.jpg: {result}"
+    return "back cover skip-if-exists OK"
+
+
 # ---------------------------------------------------------------------------
 # executor Tests
 # ---------------------------------------------------------------------------
@@ -399,6 +467,10 @@ def main() -> None:
         ("UNIT_27_is_classical_false_pop",            test_is_classical_false_for_pop),
         ("UNIT_28_is_classical_false_folk",           test_is_classical_false_for_folk),
         ("UNIT_29_normalize_cover_renames",           test_normalize_cover_renames_front_jpg),
+        ("UNIT_30_itunes_url_none_handling",          test_itunes_cover_url_format),
+        ("UNIT_31_discogs_tracklist_format",          test_discogs_tracklist_format),
+        ("UNIT_32_lastfm_tracklist_format",           test_lastfm_tracklist_format),
+        ("UNIT_33_back_cover_skip_if_exists",         test_back_cover_skips_if_exists),
     ]
 
     for test_id, fn in cases: