feat: Introduce DefaultExtractor for fallback values and refactor extraction logic in MediaExtractor

renamer/extractors/default_extractor.py

@@ -0,0 +1,50 @@
+class DefaultExtractor:
+    """Extractor that provides default fallback values"""
+
+    def extract_title(self):
+        return "Unknown Title"
+
+    def extract_year(self):
+        return None
+
+    def extract_source(self):
+        return None
+
+    def extract_resolution(self):
+        return None
+
+    def extract_hdr(self):
+        return None
+
+    def extract_movie_db(self):
+        return None
+
+    def extract_audio_langs(self):
+        return None
+
+    def extract_meta_type(self):
+        return None
+
+    def extract_size(self):
+        return None
+
+    def extract_modification_time(self):
+        return None
+
+    def extract_file_name(self):
+        return None
+
+    def extract_file_path(self):
+        return None
+
+    def extract_frame_class(self):
+        return None
+
+    def extract_video_tracks(self):
+        return []
+
+    def extract_audio_tracks(self):
+        return []
+
+    def extract_subtitle_tracks(self):
+        return []

renamer/extractors/filename_extractor.py

@@ -12,12 +12,12 @@ class FilenameExtractor:
         self.file_path = file_path
         self.file_name = file_path.name
 
-    def _get_frame_class_from_height(self, height: int) -> str:
+    def _get_frame_class_from_height(self, height: int) -> str | None:
         """Get frame class from video height using FRAME_CLASSES constant"""
         for frame_class, info in FRAME_CLASSES.items():
             if height == info['nominal_height']:
                 return frame_class
-        return 'Unclassified'
+        return None
 
     def extract_title(self) -> str | None:
         """Extract movie title from filename"""
@@ -126,9 +126,9 @@ class FilenameExtractor:
         unclassified_indicators = ['SD', 'LQ', 'HD', 'QHD']
         for indicator in unclassified_indicators:
             if re.search(r'\b' + re.escape(indicator) + r'\b', self.file_name, re.IGNORECASE):
-                return 'Unclassified'
+                return None
         
-        return 'Unclassified'
+        return None
 
     def extract_hdr(self) -> str | None:
         """Extract HDR information from filename"""

renamer/extractors/mediainfo_extractor.py

@@ -26,7 +26,7 @@ class MediaInfoExtractor:
         for frame_class, info in FRAME_CLASSES.items():
             if height == info['nominal_height']:
                 return frame_class
-        return 'Unclassified'
+        return None
 
     def extract_duration(self) -> float | None:
         """Extract duration from media info in seconds"""
@@ -39,11 +39,11 @@ class MediaInfoExtractor:
     def extract_frame_class(self) -> str | None:
         """Extract frame class from media info (480p, 720p, 1080p, etc.)"""
         if not self.video_tracks:
-            return 'Unclassified'
+            return None
         height = getattr(self.video_tracks[0], 'height', None)
         if height:
             return self._get_frame_class_from_height(height)
-        return 'Unclassified'
+        return None
 
     def extract_resolution(self) -> tuple[int, int] | None:
         """Extract actual video resolution as (width, height) tuple from media info"""