Refactor CLI implementation and move it to it's own file

cli.py

@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+from argparse import ArgumentParser
+from os import remove
+from sys import exit
+from signal import signal, SIGINT
+from multiprocessing import Pool, cpu_count
+
+from imgrate import imgrate
+
+
+class Cli:
+    def __init__(self):
+        self.args = None
+        self.image_ratings = None
+        self.best_image = None
+
+    def __call__(self):
+        signal(SIGINT, lambda a, b: exit('\nExiting!'))
+
+        self.parse_arguments()
+
+        if not hasattr(imgrate, self.args.method):
+            exit('Invalid --method option!')
+
+        self.calculate_ratings()
+        self.best_image = max(self.image_ratings, key=self.image_ratings.get)
+        self.print_ratings()
+
+        if self.args.delete:
+            self.keep_best_quality_image_only()
+
+    def parse_arguments(self):
+        ap = ArgumentParser(description='Find the best quality one among similar images.'
+                                        'Note: image dimensions should match!')
+        ap.add_argument('images', type=str, nargs='+',
+                        help='')
+        ap.add_argument('-d', '--delete', action='store_true',
+                        help='Delete all but the best quality image.')
+        ap.add_argument('-q', '--quiet', action='store_true',
+                        help='Print quality measurements only.')
+        ap.add_argument('-m', '--method', type=str, default='quality',
+                        help='Select quality measurement to use.')
+        self.args = ap.parse_args()
+
+    def calculate_ratings(self):
+        ratings = []
+        with Pool(processes=cpu_count()) as pool:
+            for image in self.args.images:
+                ratings.append((image, pool.apply_async(self.calculate_rating,
+                                                        (image, self.args.method))))
+            self.image_ratings = {image: promise.get() for image, promise in ratings}
+
+    @staticmethod
+    def calculate_rating(image, method):
+        return getattr(imgrate(image), method)
+
+    def print_ratings(self):
+        for image in self.image_ratings.keys():
+            if self.args.quiet:
+                print(self.image_ratings[image])
+            else:
+                max_marker = '*' if image == self.best_image and len(self.image_ratings) > 1 else ' '
+                print(f'{max_marker}imgrate("{image}") = {self.image_ratings[image]}')
+
+    def keep_best_quality_image_only(self):
+        for image in self.image_ratings.keys():
+            if image != self.best_image:
+                remove(image)
+
+
+if __name__ == '__main__':
+    Cli()()

imgrate.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python3
-from argparse import ArgumentParser
 from functools import wraps
 
 import cv2
@@ -45,60 +43,3 @@ class imgrate:
         Fmax = Fabs.max()
         Th = np.count_nonzero(Fabs > Fmax/1000)
         return Th / (F.shape[0] * F.shape[1])
-
-
-if __name__ == '__main__':
-    from os import remove
-    from sys import exit
-    from signal import signal, SIGINT
-    from multiprocessing import Pool, cpu_count
-
-    signal(SIGINT, lambda a, b: exit('\nExiting!'))
-
-
-    def parse_arguments():
-        ap = ArgumentParser(description='Find the best quality one among similar images.'
-                                        'Note: image dimensions should match!')
-        ap.add_argument('images', type=str, nargs='+', help='')
-        ap.add_argument('-d', '--delete', action='store_true', help='Delete all but the best quality image.')
-        ap.add_argument('-q', '--quiet', action='store_true', help='Print quality measurements only.')
-        ap.add_argument('-m', '--method', type=str, default='quality', help='Select quality measurement to use.')
-        return ap.parse_args()
-
-
-    def run(args):
-        if not hasattr(imgrate, args.method):
-            exit('Invalid --method option!')
-
-        ratings = calculate_all_ratings(args.images, args.method)
-        maximum = max(ratings, key=ratings.get)
-
-        fancy_print_ratings(ratings, args.quiet, maximum)
-
-        if args.delete:
-            [remove(image) for image in ratings if image != maximum]
-
-
-    def calculate_all_ratings(images, method):
-        ratings = []
-        with Pool(processes=cpu_count()) as pool:
-            for image in images:
-                ratings.append((image, pool.apply_async(calculate_rating, (image, method))))
-
-            return {image: promise.get() for image, promise in ratings}
-
-
-    def calculate_rating(image, method):
-        return getattr(imgrate(image), method)
-
-
-    def fancy_print_ratings(ratings, quiet, maximum):
-        for rating in ratings.keys():
-            if quiet:
-                print(ratings[rating])
-            else:
-                maxmark = '*' if rating == maximum and len(ratings) > 1 else ' '
-                print('{}imgrate("{}") = {}'.format(maxmark, rating, ratings[rating]))
-
-
-    run(parse_arguments())