[extractor/rutube] Extract chapters from description (#6345)

Authored by: mushbite

1 files changed, 32 insertions, 0 deletions

diff --git a/yt_dlp/extractor/common.py b/yt_dlp/extractor/common.py
index 8ad63b411..2091df7fa 100644
--- a/yt_dlp/extractor/common.py
+++ b/yt_dlp/extractor/common.py
@@ -3649,6 +3649,38 @@ class InfoExtractor:
                 or urllib.parse.unquote(os.path.splitext(url_basename(url))[0])
                 or default)
 
+    def _extract_chapters_helper(self, chapter_list, start_function, title_function, duration, strict=True):
+        if not duration:
+            return
+        chapter_list = [{
+            'start_time': start_function(chapter),
+            'title': title_function(chapter),
+        } for chapter in chapter_list or []]
+        if not strict:
+            chapter_list.sort(key=lambda c: c['start_time'] or 0)
+
+        chapters = [{'start_time': 0}]
+        for idx, chapter in enumerate(chapter_list):
+            if chapter['start_time'] is None:
+                self.report_warning(f'Incomplete chapter {idx}')
+            elif chapters[-1]['start_time'] <= chapter['start_time'] <= duration:
+                chapters.append(chapter)
+            elif chapter not in chapters:
+                self.report_warning(
+                    f'Invalid start time ({chapter["start_time"]} < {chapters[-1]["start_time"]}) for chapter "{chapter["title"]}"')
+        return chapters[1:]
+
+    def _extract_chapters_from_description(self, description, duration):
+        duration_re = r'(?:\d+:)?\d{1,2}:\d{2}'
+        sep_re = r'(?m)^\s*(%s)\b\W*\s(%s)\s*$'
+        return self._extract_chapters_helper(
+            re.findall(sep_re % (duration_re, r'.+?'), description or ''),
+            start_function=lambda x: parse_duration(x[0]), title_function=lambda x: x[1],
+            duration=duration, strict=False) or self._extract_chapters_helper(
+            re.findall(sep_re % (r'.+?', duration_re), description or ''),
+            start_function=lambda x: parse_duration(x[1]), title_function=lambda x: x[0],
+            duration=duration, strict=False)
+
     @staticmethod
     def _availability(is_private=None, needs_premium=None, needs_subscription=None, needs_auth=None, is_unlisted=None):
         all_known = all(map(