Added an auto rename option and fixed the force option

I've noticed that if I am downloading two videos with same names from youtube (e.g. https://www.youtube.com/watch?v=606hmlA_nxw and https://www.youtube.com/watch?v=CLrXTnggUeY), only one of them will be saved (usually the bigger one according to the original script "os.path.getsize(output_filepath) >= total_size * 0.9"). However, I want them both while preserving their names from youtube. So I modified the source code. It looks like there are a lot of changes, but I just added an indent and everything changed.
Also, I've noticed that "force" is not working at all. I fixed that issue.

src/you_get/common.py

@@ -134,6 +134,7 @@ player = None
 extractor_proxy = None
 cookies = None
 output_filename = None
+auto_rename = False
 
 fake_headers = {
     'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',  # noqa
@@ -598,6 +599,9 @@ def url_save(
         tmp_headers['Referer'] = refer
     file_size = url_size(url, faker=faker, headers=tmp_headers)
 
+    continue_renameing = True
+    while continue_renameing:
+        continue_renameing = False
         if os.path.exists(filepath):
             if not force and file_size == os.path.getsize(filepath):
                 if not is_part:
@@ -616,6 +620,16 @@ def url_save(
                 if not is_part:
                     if bar:
                         bar.done()
+                    if not force and auto_rename:
+                        path, ext = os.path.basename(filepath).rsplit('.', 1)
+                        if (re.compile(' \(\d\)').match(path[-4:]) is None):
+                            thisfile = path + ' (1).' + ext
+                        else:
+                            thisfile = path[:-2] + str(int(path[-2]) + 1) + ').' + ext 
+                        filepath = os.path.join(os.path.dirname(filepath), thisfile)
+                        print('Changing name to %s' % tr(os.path.basename(filepath)), '...')
+                        continue_renameing = True
+                        continue
                     print('Overwriting %s' % tr(os.path.basename(filepath)), '...')
         elif not os.path.exists(os.path.dirname(filepath)):
             os.mkdir(os.path.dirname(filepath))
@@ -883,7 +897,7 @@ def download_urls(
     output_filepath = os.path.join(output_dir, output_filename)
 
     if total_size:
-        if not force and os.path.exists(output_filepath) \
+        if not force and os.path.exists(output_filepath) and not auto_rename\
                 and os.path.getsize(output_filepath) >= total_size * 0.9:
             print('Skipping %s: file already exists' % output_filepath)
             print()
@@ -1370,6 +1384,10 @@ def script_main(download, download_playlist, **kwargs):
         '-l', '--playlist', action='store_true',
         help='Prefer to download a playlist'
     )
+    download_grp.add_argument(
+        '-a', '--auto-rename', action='store_true', default=False,
+        help='Auto rename same name different files'
+    )
 
     proxy_grp = parser.add_argument_group('Proxy options')
     proxy_grp = proxy_grp.add_mutually_exclusive_group()
@@ -1414,11 +1432,16 @@ def script_main(download, download_playlist, **kwargs):
     global player
     global extractor_proxy
     global output_filename
+    global auto_rename
 
     output_filename = args.output_filename
     extractor_proxy = args.extractor_proxy
 
     info_only = args.info
+    if args.force:
+        force = True
+    if args.auto_rename:
+        auto_rename = True
     if args.url:
         dry_run = True
     if args.json: