Barely working. (Somehow TinyTag removes all "b"s at the beginning of the string tag.)

smalltag/smalltag.py

@@ -1,7 +1,70 @@
 #!/usr/bin/python3
 
-from tinytag import TinyTag
+from __future__ import annotations
+from tinytag import TinyTag, UnsupportedFormatError
+
+
+if False:  # just stole this lazy import type hinting trick from tinytag
+    from collections.abc import Callable, Iterator  # noqa
+    from typing import Any, BinaryIO, Dict, List
 
 
 class SmallTag(TinyTag):
-    pass
+    @classmethod
+    def _get_parser_class(
+            cls,
+            filename: str | None = None,
+            filehandle: BinaryIO | None = None
+    ) -> type[SmallTag]:
+        if cls != SmallTag:
+            return cls
+        if filename:
+            parser_class = cls._get_parser_for_filename(filename)
+            if parser_class is not None:
+                return parser_class
+        # try determining the file type by magic byte header
+        if filehandle:
+            parser_class = cls._get_parser_for_file_handle(filehandle)
+            if parser_class is not None:
+                return parser_class
+        raise UnsupportedFormatError(
+            'No tag reader found to support file type')
+
+    def write(self, file_obj: BinaryIO = None):
+        raise NotImplementedError
+
+    def _set_filehandler_for_writing(self, file_obj: BinaryIO) -> bool:
+        should_close_file = file_obj is None and not self._filehandler.writable()
+
+        if self.filename is None and should_close_file:
+            raise ValueError(
+                "You must specify a new file object that is in write mode. "
+                "(Has to be from the same file as specified while creating this TinyTag instance.)"
+            )
+
+        if file_obj is not None and not self._filehandler.closed():
+            self._filehandler.close()
+
+        if file_obj is not None:
+            self._filehandler = file_obj
+
+        else:
+            self._filehandler = open(self.filename, "rb+")
+
+        return should_close_file
+
+
+# import formats after SmallTag definition to avoid circular imports
+# (this solution is stupid, but I don't know anything better.)
+from ._formats import _ID3  # noqa
+
+SmallTag._file_extension_mapping = {
+        ('.mp1', '.mp2', '.mp3'): _ID3,
+        # ('.oga', '.ogg', '.opus', '.spx'): _Ogg,  (Not yet implemented.)
+        # ('.wav',): _Wave,
+        # ('.flac',): _Flac,
+        # ('.wma',): _Wma,
+        # ('.m4b', '.m4a', '.m4r', '.m4v', '.mp4',
+        #  '.aax', '.aaxc'): _MP4,
+        # ('.aiff', '.aifc', '.aif', '.afc'): _Aiff,
+}