draft: post process song

music_kraken/download/page_attributes.py

@@ -279,11 +279,25 @@ class Pages:
 
         # if everything went right, the file should exist now
         if not tmp.exists:
-            r.error_message = f"The song {song.option_string} couldn't be downloaded."
+            if used_source is None:
+                r.error_message = f"No source found for {song.option_string}."
+            else:
+                r.error_message = f"Something went wrong downloading {song.option_string}."
             return r
 
         # post process the audio
+        found_on_disk = used_source is None
+        if not found_on_disk or self.download_options.process_audio_if_found:
+            correct_codec(target=tmp, skip_intervals=skip_intervals)
+            r.sponsor_segments = len(skip_intervals)
 
+        if used_source is not None:
+            used_source.page.post_process_hook(song=song, temp_target=tmp)
+
+        if not found_on_disc or self.download_options.process_metadata_if_found:
+            write_metadata_to_target(metadata=song.metadata, target=tmp, song=song)
+
+        tmp.delete()
         return r
 
     def fetch_url(self, url: str, stop_at_level: int = 2) -> Tuple[Type[Page], DataObject]: