config: bump VERSION v1.8.4

api/bridge.py

@@ -10,7 +10,7 @@ import time
 import webbrowser
 from dataclasses import asdict
 from pathlib import Path
-from typing import Any, Optional
+from typing import Any, Callable, Optional
 
 import requests
 
@@ -32,6 +32,7 @@ from core.spotify_client import (
     SpotifyAuthRequired,
 )
 from core.metadata import read_metadata, write_metadata, SUPPORTED_EXTS
+from core import tagger
 from core.recorder import (
     list_input_devices,
     start_recording,
@@ -516,13 +517,20 @@ class Api:
     def start_tracks_download(self, payload: dict) -> dict:
         """Avvia il download di una tracklist gia parsata
         (lista di {name, artist}). Se 'subfolder' e presente,
-        scarica in output_dir/subfolder."""
+        scarica in output_dir/subfolder.
+
+        `payload['metadata']` opzionale: lista parallela a `tracks` con dict
+        per il tagging ID3 (title, artist, album, date, genre, tracknumber,
+        cover_url). Se presente, i file MP3 vengono nominati come
+        "Artista - Titolo.mp3" e taggati post-download.
+        """
         if self._any_job_running():
             return {"ok": False, "error": "Un download gia in corso"}
 
         tracks = payload.get("tracks") or []
         output_dir = (payload.get("output_dir") or "").strip()
         subfolder = (payload.get("subfolder") or "").strip()
+        metadata_list = payload.get("metadata") or None
         if not tracks:
             return {"ok": False, "error": "Nessuna traccia fornita"}
         if not output_dir:
@@ -541,6 +549,7 @@ class Api:
         self._download_thread = threading.Thread(
             target=self._tracks_worker,
             args=(list(tracks), output_dir),
+            kwargs={"metadata_list": list(metadata_list) if metadata_list else None},
             daemon=True,
         )
         self._download_thread.start()
@@ -548,7 +557,13 @@ class Api:
 
     def start_urls_download(self, payload: dict) -> dict:
         """Analogo a start_tracks_download ma accetta URL YouTube gia noti
-        (bypass search). Usato dal flow del tab 'YouTube Search'."""
+        (bypass search). Usato dal flow del tab 'YouTube Search'.
+
+        `payload['metadata']` opzionale: lista parallela a `urls` con dict
+        per il tagging ID3 (title, artist, album, date, genre, tracknumber,
+        cover_url). Se presente, i file MP3 vengono nominati come
+        "Artista - Titolo.mp3" e taggati post-download.
+        """
         if self._any_job_running():
             return {"ok": False, "error": "Un download gia in corso"}
 
@@ -556,6 +571,7 @@ class Api:
         titles = payload.get("titles") or []
         output_dir = (payload.get("output_dir") or "").strip()
         subfolder = (payload.get("subfolder") or "").strip()
+        metadata_list = payload.get("metadata") or None
         if not urls:
             return {"ok": False, "error": "Nessuna URL fornita"}
         if len(urls) != len(titles):
@@ -575,6 +591,7 @@ class Api:
         self._download_thread = threading.Thread(
             target=self._urls_worker,
             args=(list(urls), list(titles), output_dir),
+            kwargs={"metadata_list": list(metadata_list) if metadata_list else None},
             daemon=True,
         )
         self._download_thread.start()
@@ -585,7 +602,8 @@ class Api:
         self._log("download", "[INFO] Interruzione richiesta...")
         return {"ok": True}
 
-    def _tracks_worker(self, tracks: list, output_dir: str) -> None:
+    def _tracks_worker(self, tracks: list, output_dir: str,
+                        metadata_list: Optional[list] = None) -> None:
         reset_download_stop()
         cfg = load_config()
         bitrate = cfg.get("bitrate", "320K")
@@ -595,6 +613,31 @@ class Api:
         self._log(view, f"[INFO] Tracklist: {len(tracks)} brani da cercare su YouTube")
         self._log(view, f"[INFO] Destinazione: {output_dir}")
 
+        # Pipeline tagging: se metadata_list fornito, calcola i filename
+        # ("Artista - Titolo") e prepara callback per scrivere ID3 tag
+        # + cover art dopo ogni download riuscito.
+        output_filenames: Optional[list] = None
+        post_cb: Optional[Callable] = None
+        if metadata_list:
+            output_filenames = []
+            for md in metadata_list:
+                md = md or {}
+                stem = tagger.build_filename_stem(
+                    md.get("artist", ""),
+                    md.get("title", ""),
+                )
+                output_filenames.append(stem)
+
+            def post_cb(idx: int, filepath: str,
+                        _md_list=metadata_list) -> None:
+                if idx < 0 or idx >= len(_md_list):
+                    return
+                md = _md_list[idx] or {}
+                try:
+                    tagger.write_tags(filepath, md)
+                except Exception:
+                    pass  # tagging best-effort, non blocca il download
+
         _last = [0.0]
         _THROTTLE = 0.10
 
@@ -634,10 +677,15 @@ class Api:
 
             self._emit("download:progress", payload_evt)
 
-        download_playlist(tracks, output_dir, bitrate, cookies_path, progress_cb)
+        download_playlist(
+            tracks, output_dir, bitrate, cookies_path, progress_cb,
+            output_filenames=output_filenames,
+            post_download_callback=post_cb,
+        )
         self._emit("download:done", {"ok": True})
 
-    def _urls_worker(self, urls: list, titles: list, output_dir: str) -> None:
+    def _urls_worker(self, urls: list, titles: list, output_dir: str,
+                      metadata_list: Optional[list] = None) -> None:
         from core.downloader import download_urls
         reset_download_stop()
         cfg = load_config()
@@ -648,6 +696,29 @@ class Api:
         self._log(view, f"[INFO] URL list: {len(urls)} da scaricare da YouTube")
         self._log(view, f"[INFO] Destinazione: {output_dir}")
 
+        # Stessa pipeline tagging di _tracks_worker
+        output_filenames: Optional[list] = None
+        post_cb: Optional[Callable] = None
+        if metadata_list:
+            output_filenames = []
+            for md in metadata_list:
+                md = md or {}
+                stem = tagger.build_filename_stem(
+                    md.get("artist", ""),
+                    md.get("title", ""),
+                )
+                output_filenames.append(stem)
+
+            def post_cb(idx: int, filepath: str,
+                        _md_list=metadata_list) -> None:
+                if idx < 0 or idx >= len(_md_list):
+                    return
+                md = _md_list[idx] or {}
+                try:
+                    tagger.write_tags(filepath, md)
+                except Exception:
+                    pass  # tagging best-effort, non blocca il download
+
         _last = [0.0]
         _THROTTLE = 0.10
 
@@ -681,7 +752,11 @@ class Api:
 
             self._emit("download:progress", payload_evt)
 
-        download_urls(urls, titles, output_dir, bitrate, cookies_path, progress_cb)
+        download_urls(
+            urls, titles, output_dir, bitrate, cookies_path, progress_cb,
+            output_filenames=output_filenames,
+            post_download_callback=post_cb,
+        )
         self._emit("download:done", {"ok": True})
 
     def _download_worker(self, urls: list, output_dir: str) -> None:
@@ -1167,7 +1242,13 @@ class Api:
         return result
 
     def spotify_search_download(self, tracks: list) -> dict:
-        """Scarica i track Spotify selezionati (name+artist → YouTube search)."""
+        """Scarica i track Spotify selezionati (name+artist → YouTube search).
+
+        Costruisce anche `metadata` (una entry per track) per il tagging ID3
+        + cover art post-download. Se le creds Spotify sono presenti,
+        arricchisce con i generi dell'artista (cache locale per artist_id
+        per evitare N+1 chiamate).
+        """
         cfg = load_config()
         out_root = (cfg.get("output_dir") or "").strip()
         if not out_root:
@@ -1176,7 +1257,20 @@ class Api:
         target = self._music_output_dir(out_root, "Spotify")
         subfolder = target.name
 
-        converted = []
+        # Tentativo di token Spotify per fetch generi (best-effort, opzionale)
+        cid = (cfg.get("client_id") or "").strip()
+        secret = (cfg.get("client_secret") or "").strip()
+        token: Optional[str] = None
+        if cid and secret:
+            try:
+                token = spotify_client.get_access_token(cid, secret)
+            except Exception:
+                token = None
+
+        genre_cache: dict = {}  # artist_id -> [genres]
+
+        converted: list = []
+        metadata: list = []
         for t in tracks:
             title = (t.get("name") or "").strip()
             artists = (t.get("artists") or "").strip()
@@ -1184,6 +1278,27 @@ class Api:
                 continue
             converted.append({"name": title, "artist": artists})
 
+            # Genere: primo genere dell'artista (se disponibile e token OK)
+            genre = ""
+            artist_id = (t.get("artist_id") or "").strip()
+            if token and artist_id:
+                if artist_id not in genre_cache:
+                    genre_cache[artist_id] = spotify_client.get_artist_genres(token, artist_id)
+                genres = genre_cache.get(artist_id) or []
+                if genres:
+                    genre = genres[0]
+
+            tn = t.get("track_number") or 0
+            metadata.append({
+                "title": title,
+                "artist": artists,
+                "album": (t.get("album") or "").strip(),
+                "date": (t.get("release_date") or "").strip(),
+                "genre": genre,
+                "tracknumber": str(tn) if tn else "",
+                "cover_url": (t.get("cover_url_large") or t.get("image_url") or "").strip(),
+            })
+
         if not converted:
             return {"ok": False, "error": "Nessun brano valido"}
 
@@ -1191,6 +1306,7 @@ class Api:
             "tracks": converted,
             "output_dir": out_root,
             "subfolder": subfolder,
+            "metadata": metadata,
         })
 
     # ---- YouTube ----
@@ -1242,7 +1358,14 @@ class Api:
         return result
 
     def youtube_search_download(self, tracks: list) -> dict:
-        """Scarica direttamente gli URL YouTube selezionati (no re-search)."""
+        """Scarica direttamente gli URL YouTube selezionati (no re-search).
+
+        Per ogni video prova a dedurre i metadati:
+        1) Se le creds Spotify sono presenti, cerca il titolo su Spotify
+           e usa i tag Spotify se c'è un match (best-effort).
+        2) Altrimenti fallback: parsing "Artista - Titolo" dal titolo del
+           video; uploader come fallback per l'album.
+        """
         cfg = load_config()
         out_root = (cfg.get("output_dir") or "").strip()
         if not out_root:
@@ -1251,8 +1374,21 @@ class Api:
         target = self._music_output_dir(out_root, "YouTube")
         subfolder = target.name
 
+        # Token Spotify opzionale per enrichment
+        cid = (cfg.get("client_id") or "").strip()
+        secret = (cfg.get("client_secret") or "").strip()
+        token: Optional[str] = None
+        if cid and secret:
+            try:
+                token = spotify_client.get_access_token(cid, secret)
+            except Exception:
+                token = None
+
+        genre_cache: dict = {}  # artist_id -> [genres]
+
         urls: list = []
         titles: list = []
+        metadata: list = []
         for t in tracks:
             url = (t.get("url") or "").strip()
             title = (t.get("title") or "").strip()
@@ -1261,6 +1397,51 @@ class Api:
             urls.append(url)
             titles.append(title)
 
+            md: dict = {}
+            # 1) Enrichment via Spotify search (se token)
+            if token:
+                sp = spotify_client.enrich_from_youtube_title(token, title)
+                if sp:
+                    # Genere: opzionale
+                    genre = ""
+                    artist_id = (sp.get("artist_id") or "").strip()
+                    if artist_id:
+                        if artist_id not in genre_cache:
+                            genre_cache[artist_id] = spotify_client.get_artist_genres(token, artist_id)
+                        genres = genre_cache.get(artist_id) or []
+                        if genres:
+                            genre = genres[0]
+                    tn = sp.get("track_number") or 0
+                    md = {
+                        "title": (sp.get("name") or "").strip(),
+                        "artist": (sp.get("artists") or "").strip(),
+                        "album": (sp.get("album") or "").strip(),
+                        "date": (sp.get("release_date") or "").strip(),
+                        "genre": genre,
+                        "tracknumber": str(tn) if tn else "",
+                        "cover_url": (sp.get("cover_url_large") or sp.get("image_url") or "").strip(),
+                    }
+
+            # 2) Fallback: parsing del titolo YouTube
+            if not md.get("title") or not md.get("artist"):
+                parsed = _parse_track_line(title)
+                if parsed:
+                    fb_artist = parsed["artist"]
+                    fb_title = parsed["name"]
+                else:
+                    fb_artist = ""
+                    fb_title = title
+                md = {
+                    "title": fb_title,
+                    "artist": fb_artist,
+                    "album": (t.get("channel") or "").strip(),
+                    "date": (t.get("release_date") or "").strip(),
+                    "genre": "",
+                    "tracknumber": "",
+                    "cover_url": (t.get("image_url") or "").strip(),
+                }
+            metadata.append(md)
+
         if not urls:
             return {"ok": False, "error": "Nessun URL valido"}
 
@@ -1269,4 +1450,5 @@ class Api:
             "titles": titles,
             "output_dir": out_root,
             "subfolder": subfolder,
+            "metadata": metadata,
         })

core/config.py

@@ -5,7 +5,7 @@ import os
 import sys
 from pathlib import Path
 
-VERSION = "v1.8.3"
+VERSION = "v1.8.4"
 
 
 APP_NAME = "MusicTools"

core/downloader.py

@@ -121,6 +121,8 @@ def download_playlist(
     bitrate: str = "320K",
     cookies_path: Optional[str] = None,
     progress_callback: Optional[Callable] = None,
+    output_filenames: Optional[list] = None,
+    post_download_callback: Optional[Callable] = None,
 ) -> None:
     """Scarica tutti i brani dalla lista di tracce.
 
@@ -130,6 +132,12 @@ def download_playlist(
         bitrate: qualita audio (es. "320K")
         cookies_path: percorso file cookies (opzionale)
         progress_callback: callback(track_index, total, track_name, status, percent)
+        output_filenames: opzionale, parallelo a `tracks`. Se presente e non
+            vuoto per l'indice i, yt-dlp scrive `<output_filenames[i]>.mp3`
+            invece di usare il titolo YouTube. Passa gia' sanitizzato.
+        post_download_callback: opzionale, chiamato come `(i, filepath)`
+            dopo yt-dlp exit 0 con il path effettivo del file .mp3 salvato.
+            Usato per tagging ID3 post-download.
     """
     reset_stop()
     total = len(tracks)
@@ -183,6 +191,15 @@ def download_playlist(
         if progress_callback:
             progress_callback(i, total, query, "downloading", 0)
 
+        # Nome file custom (per tagging: "Artista - Titolo") oppure titolo YouTube grezzo
+        custom_stem = ""
+        if output_filenames and i < len(output_filenames):
+            custom_stem = (output_filenames[i] or "").strip()
+        if custom_stem:
+            out_template = str(Path(output_dir) / f"{custom_stem}.%(ext)s")
+        else:
+            out_template = str(Path(output_dir) / "%(title)s.%(ext)s")
+
         # Scarica con yt-dlp subprocess
         cmd = [
             ytdlp,
@@ -193,7 +210,7 @@ def download_playlist(
             "--add-metadata",
             "--no-check-certificates",
             "--newline",
-            "--output", str(Path(output_dir) / "%(title)s.%(ext)s"),
+            "--output", out_template,
             video_url,
         ]
         ffmpeg_dir = find_ffmpeg_dir()
@@ -231,6 +248,12 @@ def download_playlist(
                 _mark_done(done_file, query)
                 done_set.add(query)
                 existing_files = _scan_existing_files(out_path)
+                if post_download_callback and custom_stem:
+                    mp3_path = Path(output_dir) / f"{custom_stem}.mp3"
+                    try:
+                        post_download_callback(i, str(mp3_path))
+                    except Exception:
+                        pass
                 if progress_callback:
                     progress_callback(i, total, query, "done", 100)
             else:
@@ -406,6 +429,8 @@ def download_urls(
     bitrate: str = "320K",
     cookies_path: Optional[str] = None,
     progress_callback: Optional[Callable] = None,
+    output_filenames: Optional[list] = None,
+    post_download_callback: Optional[Callable] = None,
 ) -> None:
     """Scarica direttamente da URL YouTube (bypassa search).
 
@@ -420,6 +445,12 @@ def download_urls(
         bitrate: qualita audio (default 320K)
         cookies_path: file cookies opzionale
         progress_callback: callback(idx, total, title, status, percent)
+        output_filenames: opzionale, parallelo a `urls`. Se presente e non
+            vuoto per l'indice i, yt-dlp scrive `<output_filenames[i]>.mp3`
+            invece di usare il titolo YouTube. Passa gia' sanitizzato.
+        post_download_callback: opzionale, chiamato come `(i, filepath)`
+            dopo yt-dlp exit 0 con il path effettivo del file .mp3 salvato.
+            Usato per tagging ID3 post-download.
     """
     global _current_process
     reset_stop()
@@ -456,6 +487,15 @@ def download_urls(
         if progress_callback:
             progress_callback(i, total, key, "downloading", 0)
 
+        # Nome file custom (per tagging: "Artista - Titolo") oppure titolo YouTube grezzo
+        custom_stem = ""
+        if output_filenames and i < len(output_filenames):
+            custom_stem = (output_filenames[i] or "").strip()
+        if custom_stem:
+            out_template = str(Path(output_dir) / f"{custom_stem}.%(ext)s")
+        else:
+            out_template = str(Path(output_dir) / "%(title)s.%(ext)s")
+
         cmd = [
             ytdlp,
             "--extract-audio",
@@ -465,7 +505,7 @@ def download_urls(
             "--add-metadata",
             "--no-check-certificates",
             "--newline",
-            "--output", str(Path(output_dir) / "%(title)s.%(ext)s"),
+            "--output", out_template,
             url,
         ]
         ffmpeg_dir = find_ffmpeg_dir()
@@ -502,6 +542,12 @@ def download_urls(
                 _mark_done(done_file, key)
                 done_set.add(key)
                 existing_files = _scan_existing_files(out_path)
+                if post_download_callback and custom_stem:
+                    mp3_path = Path(output_dir) / f"{custom_stem}.mp3"
+                    try:
+                        post_download_callback(i, str(mp3_path))
+                    except Exception:
+                        pass
                 if progress_callback:
                     progress_callback(i, total, key, "done", 100)
             else:

core/spotify_client.py

@@ -308,23 +308,74 @@ def search_tracks(token: str, query: str, limit: int = 50) -> list:
 
 def _track_to_dict(t: dict) -> dict:
     """Mappa il track object Spotify sul nostro schema uniforme."""
-    images = t.get("album", {}).get("images", []) or []
+    album = t.get("album", {}) or {}
+    images = album.get("images", []) or []
     # Spotify torna 3 taglie ordinate large->small. Prendo la più piccola (~64px)
-    # se disponibile, altrimenti la prima che c'è.
-    image_url = ""
+    # per la thumbnail UI, la più grande (~640px) per il tagging cover.
+    image_url = ""       # ~64px per UI thumbnail
+    cover_url_large = "" # ~640px per tagging ID3
     if images:
         image_url = images[-1].get("url", "") or images[0].get("url", "")
+        cover_url_large = images[0].get("url", "") or image_url
+    # release_date può essere YYYY, YYYY-MM o YYYY-MM-DD in base a release_date_precision
+    release_date = str(album.get("release_date") or "").strip()
+    # track_number (opzionale: presente su brani da album, assente su top-tracks flat)
+    tracknumber = t.get("track_number")
+    # artist_id (primo artista) per fetchare i generi ID3
+    artists_arr = t.get("artists", []) or []
+    artist_id = artists_arr[0].get("id", "") if artists_arr else ""
     return {
         "id": t.get("id", ""),
         "url": t.get("external_urls", {}).get("spotify", ""),
         "name": t.get("name", ""),
-        "artists": ", ".join(a.get("name", "") for a in t.get("artists", [])),
-        "album": t.get("album", {}).get("name", ""),
+        "artists": ", ".join(a.get("name", "") for a in artists_arr),
+        "album": album.get("name", ""),
         "duration_sec": int(t.get("duration_ms", 0)) // 1000,
         "image_url": image_url,
+        "cover_url_large": cover_url_large,
+        "release_date": release_date,
+        "track_number": int(tracknumber) if tracknumber else 0,
+        "artist_id": artist_id,
     }
 
 
+def get_artist_genres(token: str, artist_id: str) -> list:
+    """Ritorna la lista di generi dell'artista (può essere vuota).
+
+    Silenzia gli errori HTTP: usato per arricchimento best-effort dei tag
+    ID3, non deve mai bloccare il download.
+    """
+    if not artist_id:
+        return []
+    try:
+        resp = requests.get(
+            f"https://api.spotify.com/v1/artists/{artist_id}",
+            headers={"Authorization": f"Bearer {token}"},
+            timeout=10,
+        )
+        if resp.status_code != 200:
+            return []
+        return list(resp.json().get("genres") or [])
+    except Exception:
+        return []
+
+
+def enrich_from_youtube_title(token: str, video_title: str) -> dict:
+    """Cerca su Spotify il primo match per il titolo di un video YouTube.
+
+    Ritorna un dict con la stessa shape di _track_to_dict, oppure {} se
+    nessun match / errore. Best-effort per il tagging dei download YouTube.
+    """
+    query = (video_title or "").strip()
+    if not query:
+        return {}
+    try:
+        results = search_tracks(token, query, limit=1)
+    except Exception:
+        return {}
+    return results[0] if results else {}
+
+
 def search_artist_discography(token: str, artist_name: str) -> list:
     """Trova l'artista esatto (o il piu' popolare tra i match) e ritorna
     tutti i suoi brani: top tracks + tracce di ogni album/single.
@@ -385,6 +436,7 @@ def search_artist_discography(token: str, artist_name: str) -> list:
         alb_id = alb.get("id")
         alb_name = alb.get("name", "")
         alb_images = alb.get("images", []) or []
+        alb_release_date = alb.get("release_date", "")
         if not alb_id:
             continue
         time.sleep(0.1)  # rate limit interno
@@ -397,7 +449,11 @@ def search_artist_discography(token: str, artist_name: str) -> list:
         r_at.raise_for_status()
         for t in r_at.json().get("items", []):
             t = dict(t)
-            t.setdefault("album", {"name": alb_name, "images": alb_images})
+            t.setdefault("album", {
+                "name": alb_name,
+                "images": alb_images,
+                "release_date": alb_release_date,
+            })
             collected.append(_track_to_dict(t))
 
     # 5. Dedupe

core/tagger.py

@@ -0,0 +1,109 @@
+"""Scrittura tag ID3 su file MP3 via mutagen, con cover art da URL."""
+
+from __future__ import annotations
+
+import re
+from pathlib import Path
+from typing import Optional
+
+import requests
+from mutagen.easyid3 import EasyID3
+from mutagen.id3 import ID3, APIC
+from mutagen.mp3 import MP3
+
+
+SAFE_FILENAME_RE = re.compile(r'[<>:"/\\|?*\x00-\x1f]')
+
+
+def sanitize_filename_stem(stem: str, max_len: int = 180) -> str:
+    """Rimuove caratteri non validi per un filename e limita lunghezza."""
+    s = SAFE_FILENAME_RE.sub("_", stem or "").strip()
+    s = re.sub(r"\s+", " ", s)
+    if len(s) > max_len:
+        s = s[:max_len].rstrip()
+    return s or "untitled"
+
+
+def build_filename_stem(artist: str, title: str) -> str:
+    """Compone 'Artista - Titolo' sanitizzato."""
+    artist = (artist or "").strip()
+    title = (title or "").strip()
+    if artist and title:
+        return sanitize_filename_stem(f"{artist} - {title}")
+    return sanitize_filename_stem(title or artist or "untitled")
+
+
+def _download_cover(url: str) -> Optional[bytes]:
+    """Scarica bytes cover, ritorna None su qualsiasi errore."""
+    try:
+        resp = requests.get(url, timeout=15)
+        if resp.status_code == 200:
+            return resp.content
+    except Exception:
+        pass
+    return None
+
+
+def _cover_mime(url: str, content: bytes) -> str:
+    """Deduci MIME dell'immagine da URL o magic bytes."""
+    u = url.lower()
+    if u.endswith(".png"):
+        return "image/png"
+    if u.endswith((".jpg", ".jpeg")):
+        return "image/jpeg"
+    # magic bytes
+    if content[:8] == b"\x89PNG\r\n\x1a\n":
+        return "image/png"
+    if content[:3] == b"\xff\xd8\xff":
+        return "image/jpeg"
+    return "image/jpeg"  # default
+
+
+def write_tags(filepath: str, metadata: dict) -> None:
+    """Scrive ID3 tag su file MP3 esistente.
+
+    metadata: dict con chiavi opzionali:
+        title, artist, album, date (YYYY o YYYY-MM-DD), genre,
+        tracknumber, cover_url
+
+    Errori non fatali (file mancante, tag non scrivibili): silenziosi
+    per non bloccare il download principale.
+    """
+    p = Path(filepath)
+    if not p.exists():
+        return
+
+    # 1. Tag testuali via EasyID3
+    try:
+        try:
+            audio = EasyID3(str(p))
+        except Exception:
+            # Se il file non ha header ID3, aggiungine uno vuoto
+            mp3 = MP3(str(p))
+            if mp3.tags is None:
+                mp3.add_tags()
+                mp3.save()
+            audio = EasyID3(str(p))
+        for key in ("title", "artist", "album", "date", "genre", "tracknumber"):
+            val = metadata.get(key)
+            if val:
+                audio[key] = str(val)
+        audio.save(str(p))
+    except Exception:
+        return  # ID3 broken, non provo la cover
+
+    # 2. Cover art via ID3 APIC
+    cover_url = (metadata.get("cover_url") or "").strip()
+    if not cover_url:
+        return
+    cover_bytes = _download_cover(cover_url)
+    if not cover_bytes:
+        return
+    try:
+        mime = _cover_mime(cover_url, cover_bytes)
+        tags = ID3(str(p))
+        tags.delall("APIC")
+        tags.add(APIC(encoding=3, mime=mime, type=3, desc="Cover", data=cover_bytes))
+        tags.save(str(p))
+    except Exception:
+        pass

tests/test_tagger.py

@@ -0,0 +1,57 @@
+"""Test per core.tagger — filename sanitization + write_tags safety net."""
+
+from __future__ import annotations
+
+from core import tagger
+
+
+class TestSanitizeFilenameStem:
+    def test_removes_bad_chars(self):
+        # Tutti i char vietati su Windows/macOS: < > : " / \ | ? *
+        got = tagger.sanitize_filename_stem('bad<name>:"/\\|?*test')
+        # Nessuno dei char proibiti sopravvive
+        for ch in '<>:"/\\|?*':
+            assert ch not in got
+        # E ho ottenuto qualcosa di non vuoto
+        assert got
+
+    def test_collapses_whitespace(self):
+        assert tagger.sanitize_filename_stem("a    b    c") == "a b c"
+
+    def test_truncates_long_stem(self):
+        s = "x" * 500
+        got = tagger.sanitize_filename_stem(s, max_len=180)
+        assert len(got) <= 180
+
+    def test_empty_returns_untitled(self):
+        assert tagger.sanitize_filename_stem("") == "untitled"
+        assert tagger.sanitize_filename_stem("   ") == "untitled"
+
+
+class TestBuildFilenameStem:
+    def test_format_artist_dash_title(self):
+        assert tagger.build_filename_stem("Kapuchon", "Hot Sauce") == "Kapuchon - Hot Sauce"
+
+    def test_multiple_artists_ok(self):
+        got = tagger.build_filename_stem("Kapuchon, Miss Monique & GLZ", "Hot Sauce (Extended)")
+        assert got == "Kapuchon, Miss Monique & GLZ - Hot Sauce (Extended)"
+
+    def test_missing_artist_uses_title_only(self):
+        assert tagger.build_filename_stem("", "Only Title") == "Only Title"
+
+    def test_missing_title_uses_artist_only(self):
+        assert tagger.build_filename_stem("Only Artist", "") == "Only Artist"
+
+    def test_sanitizes_bad_chars(self):
+        got = tagger.build_filename_stem("A/B", "C:D")
+        # Nessuno slash o colon residuo
+        assert "/" not in got
+        assert ":" not in got
+
+
+class TestWriteTagsMissingFile:
+    def test_missing_file_is_noop(self):
+        # Non deve sollevare alcuna eccezione se il file non esiste
+        tagger.write_tags("/nonexistent/path/to/file.mp3", {
+            "title": "x", "artist": "y", "cover_url": "http://example.com/x.jpg",
+        })