GH-49: Enable progress using a decorator

Author: ArtyomVancyan

src/thumbnails/generator.py

@@ -12,7 +12,7 @@
 from .constants import DEFAULT_SKIP
 from .pathtools import listdir
 from .pathtools import metadata_path
-from .progress import Progress
+from .progress import use_progress
 from .thumbnail import ThumbnailExistsError
 from .thumbnail import ThumbnailFactory
 from .video import Video
@@ -46,9 +46,8 @@ def worker(video, fmt, base, skip, output):
         thumbnail.prepare_frames()
         thumbnail.generate()
 
+    @use_progress
     def generate(self):
-        Progress.stop()
-
         self.inputs = [file for file in self.inputs if re.match(r"^.*\.(?:(?!png|vtt|json).)+$", file)]
         self.inputs = dict(zip(map(lambda i: metadata_path(i, self.output, self.format), self.inputs), self.inputs))
 
@@ -73,5 +72,3 @@ def generate(self):
                 ),
                 videos,
             )
-
-        Progress.stop()

src/thumbnails/progress.py

@@ -38,3 +38,15 @@ def __exit__(self, exc_type, exc_val, _):
         if exc_type is not None:
             return self.update(exc_val, status=" ... [red]failure")
         self.update(self.done_description, status=" ... [green]success")
+
+
+def use_progress(func):
+    """Decorator for using the progress bar."""
+
+    @functools.wraps(func)
+    def wrapper(*args, **kwargs):
+        Progress.start()
+        func(*args, **kwargs)
+        Progress.stop()
+
+    return wrapper