Add per-track artist to filename: 09_Titel_-_Kuenstler.flac

- Track model: add optional artist field (None = fall back to album artist)
- organizer: append _-_<artist> to each filename
- tagger: use track.artist over album.artist for the 'artist' tag
- playlist: widen glob pattern to match new _-_<artist> suffix
- tests: update assertions + add test for track-artist override

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/musiksammlung/models.py

@@ -10,6 +10,7 @@ from pydantic import BaseModel, field_validator
 class Track(BaseModel):
     track_number: int
     title: str
+    artist: str | None = None  # Track-Künstler (z.B. bei Samplern); None = Album-Künstler
 
 
 class Disc(BaseModel):

src/musiksammlung/organizer.py

@@ -131,7 +131,8 @@ def build_mapping(
 
         for audio_file, track in zip(audio_files, disc.tracks):
             safe_title = _sanitize_filename(track.title)
-            new_name = f"{track.track_number:02d}_{safe_title}{audio_file.suffix}"
+            safe_artist = _sanitize_filename(track.artist or album.artist)
+            new_name = f"{track.track_number:02d}_{safe_title}_-_{safe_artist}{audio_file.suffix}"
             mapping[audio_file] = target_dir / new_name
 
     return mapping

src/musiksammlung/playlist.py

@@ -35,7 +35,7 @@ def generate_playlist(album: Album, album_dir: Path) -> Path:
         for track in disc.tracks:
             safe_title = _sanitize_filename(track.title)
             # Audiodatei im Zielverzeichnis finden
-            pattern = f"{track.track_number:02d}_{safe_title}.*"
+            pattern = f"{track.track_number:02d}_{safe_title}*"
             if multi_disc:
                 search_dir = album_dir / f"CD{disc.disc_number}"
             else:

src/musiksammlung/tagger.py

@@ -29,7 +29,7 @@ def tag_file(
         logger.warning("Kann Datei nicht öffnen: %s", path)
         return
 
-    audio["artist"] = album.artist
+    audio["artist"] = track.artist or album.artist
     audio["album"] = album.album
     audio["albumartist"] = album.artist
     audio["title"] = track.title

tests/test_organizer.py

@@ -167,8 +167,8 @@ class TestBuildMapping:
         mapping = build_mapping(album, tmp_path, tmp_path / "output")
 
         targets = list(mapping.values())
-        assert targets[0].name == "01_Erster_Song.flac"
-        assert targets[1].name == "02_Zweiter_Song.flac"
+        assert targets[0].name == "01_Erster_Song_-_TestArtist.flac"
+        assert targets[1].name == "02_Zweiter_Song_-_TestArtist.flac"
         # Single-Disc: kein CD1-Unterordner
         assert "CD1" not in str(targets[0])
 
@@ -207,7 +207,28 @@ class TestBuildMapping:
         # Source and target are in the same directory
         assert src.parent == tmp_path
         assert dst.parent == tmp_path
-        assert dst.name == "01_Song.flac"
+        assert dst.name == "01_Song_-_Artist.flac"
+
+    def test_track_artist_overrides_album_artist(self, tmp_path: Path) -> None:
+        (tmp_path / "track01.flac").touch()
+        (tmp_path / "track02.flac").touch()
+        album = Album(
+            artist="Various Artists",
+            album="Sampler",
+            discs=[
+                Disc(
+                    disc_number=1,
+                    tracks=[
+                        Track(track_number=1, title="Song A", artist="Artist X"),
+                        Track(track_number=2, title="Song B"),  # kein Track-Künstler → Fallback
+                    ],
+                )
+            ],
+        )
+        mapping = build_mapping(album, tmp_path, in_place=True)
+        targets = list(mapping.values())
+        assert targets[0].name == "01_Song_A_-_Artist_X.flac"
+        assert targets[1].name == "02_Song_B_-_Various_Artists.flac"
 
     def test_output_dir_structure(self, tmp_path: Path) -> None:
         (tmp_path / "track01.flac").touch()

tests/test_playlist.py

@@ -21,17 +21,17 @@ def test_generate_playlist_single_disc(tmp_path: Path):
     """M3U für Single-CD: keine CD-Prefix, korrekte Dateinamen."""
     album = _make_album(n_tracks=2, n_discs=1)
 
-    # Dummy-Audiodateien im neuen Unterstrich-Schema
-    (tmp_path / "01_Disc1_Song_1.flac").touch()
-    (tmp_path / "02_Disc1_Song_2.flac").touch()
+    # Dummy-Audiodateien mit Künstler-Suffix
+    (tmp_path / "01_Disc1_Song_1_-_Artist.flac").touch()
+    (tmp_path / "02_Disc1_Song_2_-_Artist.flac").touch()
 
     playlist_path = generate_playlist(album, tmp_path)
     assert playlist_path.exists()
 
     content = playlist_path.read_text()
     assert "#EXTM3U" in content
-    assert "01_Disc1_Song_1.flac" in content
-    assert "02_Disc1_Song_2.flac" in content
+    assert "01_Disc1_Song_1_-_Artist.flac" in content
+    assert "02_Disc1_Song_2_-_Artist.flac" in content
     # Kein CD-Prefix bei Single-Disc
     assert "CD1/" not in content
 
@@ -44,16 +44,16 @@ def test_generate_playlist_multi_disc(tmp_path: Path):
     cd2 = tmp_path / "CD2"
     cd1.mkdir()
     cd2.mkdir()
-    (cd1 / "01_Disc1_Song_1.flac").touch()
-    (cd1 / "02_Disc1_Song_2.flac").touch()
-    (cd2 / "01_Disc2_Song_1.flac").touch()
-    (cd2 / "02_Disc2_Song_2.flac").touch()
+    (cd1 / "01_Disc1_Song_1_-_Artist.flac").touch()
+    (cd1 / "02_Disc1_Song_2_-_Artist.flac").touch()
+    (cd2 / "01_Disc2_Song_1_-_Artist.flac").touch()
+    (cd2 / "02_Disc2_Song_2_-_Artist.flac").touch()
 
     playlist_path = generate_playlist(album, tmp_path)
     content = playlist_path.read_text()
 
-    assert "CD1/01_Disc1_Song_1.flac" in content
-    assert "CD2/01_Disc2_Song_1.flac" in content
+    assert "CD1/01_Disc1_Song_1_-_Artist.flac" in content
+    assert "CD2/01_Disc2_Song_1_-_Artist.flac" in content
 
 
 def test_generate_playlist_filename(tmp_path: Path):
@@ -79,7 +79,7 @@ def test_generate_playlist_extinf_contains_title(tmp_path: Path):
             )
         ],
     )
-    (tmp_path / "01_Für_Elise.flac").touch()
+    (tmp_path / "01_Für_Elise_-_A.flac").touch()
     playlist_path = generate_playlist(album, tmp_path)
     content = playlist_path.read_text()
     assert "#EXTINF:0,Für Elise" in content