VorbisComment Recommendation and Chapter Support

cozy/media/tag_reader.py

@@ -23,7 +23,7 @@ def __init__(self, uri: str, discoverer_info: GstPbutils.DiscovererInfo):
         self.discoverer_info = discoverer_info
 
         self.tags: Gst.TagList = discoverer_info.get_tags()
-
+        self._is_ogg = self.uri.lower().endswith(("opus", "ogg", "flac"))
         if not self.tags:
             raise ValueError("Failed to retrieve tags from discoverer_info")
 
@@ -53,15 +53,23 @@ def _get_book_name_fallback(self):
         return unquote(directory)
 
     def _get_author(self):
-        authors = self._get_string_list(Gst.TAG_COMPOSER)
+        authors = (
+            self._get_string_list(Gst.TAG_ARTIST)
+            if self._is_ogg
+            else self._get_string_list(Gst.TAG_COMPOSER)
+        )
 
         if len(authors) > 0 and authors[0]:
             return "; ".join(authors)
         else:
             return _("Unknown")
 
     def _get_reader(self):
-        readers = self._get_string_list(Gst.TAG_ARTIST)
+        readers = (
+            self._get_string_list(Gst.TAG_PERFORMER)
+            if self._is_ogg
+            else self._get_string_list(Gst.TAG_ARTIST)
+        )
 
         if len(readers) > 0 and readers[0]:
             return "; ".join(readers)
@@ -92,6 +100,8 @@ def _get_chapters(self):
         if self.uri.lower().endswith("m4b") and self._mutagen_supports_chapters():
             mutagen_tags = self._parse_with_mutagen()
             return self._get_m4b_chapters(mutagen_tags)
+        elif self._is_ogg:
+            return self._get_ogg_chapters()
         else:
             return self._get_single_chapter()
 
@@ -162,6 +172,55 @@ def _get_m4b_chapters(self, mutagen_tags: MP4) -> list[Chapter]:
 
         return chapters
 
+    def _get_ogg_chapters(self) -> list[Chapter]:
+        comment_list: list[str] = self._get_string_list("extended-comment")
+        chapter_dict: dict[int, list[float | str | None]] = {}
+        for comment in comment_list:
+            comment_split = comment.split("=", 1)
+            if len(comment_split) != 2:  # Is a tag set in this comment
+                continue
+            if (
+                len(comment_split[0]) not in (10, 14)
+                or comment_split[0][:7].lower() != "chapter"
+                or not comment_split[0][7:10].isdecimal()
+            ):
+                continue  # Is the tag in the form chapter + 3 numbers + maybe name
+            try:
+                chapter_num = int(comment_split[0][7:10], 10)  # get number from 3 chars
+            except ValueError:
+                continue
+            if chapter_num not in chapter_dict:
+                chapter_dict[chapter_num] = [None, None]
+            if len(comment_split[0]) == 14 and comment_split[0][10:14].lower() == "name":
+                chapter_dict[chapter_num][1] = comment_split[1]
+            elif len(comment_split[0]) == 10:
+                chapter_dict[chapter_num][0] = self._vorbis_timestamp_to_secs(comment_split[1])
+        if 0 not in chapter_dict or chapter_dict[0][0] is None or chapter_dict[0][1] is None:
+            return self._get_single_chapter()
+        i = 1
+        chapter_list: list[Chapter] = []
+        while (
+            i in chapter_dict and chapter_dict[i][0] is not None and chapter_dict[i][1] is not None
+        ):
+            chapter_list.append(
+                Chapter(
+                    name=chapter_dict[i - 1][1],
+                    position=int(chapter_dict[i - 1][0] * NS_TO_SEC),
+                    length=chapter_dict[i][0] - chapter_dict[i - 1][0],
+                    number=i,
+                )
+            )
+            i += 1
+        chapter_list.append(
+            Chapter(
+                name=chapter_dict[i - 1][1],
+                position=int(chapter_dict[i - 1][0] * NS_TO_SEC),
+                length=self._get_length_in_seconds() - chapter_dict[i - 1][0],
+                number=i,
+            )
+        )
+        return chapter_list
+
     def _parse_with_mutagen(self) -> MP4:
         path = unquote(urlparse(self.uri).path)
         mutagen_mp4 = MP4(path)
@@ -174,3 +233,13 @@ def _mutagen_supports_chapters() -> bool:
             return True
 
         return mutagen.version[0] == 1 and mutagen.version[1] >= 45
+
+    @staticmethod
+    def _vorbis_timestamp_to_secs(timestamp: str) -> float | None:
+        elems = timestamp.split(":")
+        if len(elems) != 3:
+            return None
+        try:
+            return int(elems[0], 10) * 3600 + int(elems[1], 10) * 60 + float(elems[2])
+        except ValueError:
+            return None