Make sure that image can be opened

Checking for file extension does not ensure that the image file can be
actually opened. Check if it can be loaded into a pixbuf, and convert it if
necessary.

cartridges/store/managers/cover_manager.py

@@ -19,10 +19,10 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 from pathlib import Path
-from typing import NamedTuple
+from typing import NamedTuple, Optional
 
 import requests
-from gi.repository import GdkPixbuf, Gio
+from gi.repository import GdkPixbuf, Gio, GLib
 from requests.exceptions import HTTPError, SSLError
 
 from cartridges import shared
@@ -128,9 +128,20 @@ class CoverManager(Manager):
         """
 
         # Load source image
+        try:
             source = GdkPixbuf.Pixbuf.new_from_file(
-            str(convert_cover(image_path, resize=False))
+                str(image_path)
             )
+        except GLib.Error:
+            new_path = convert_cover(image_path, resize=False)
+
+            if new_path:
+                source = GdkPixbuf.Pixbuf.new_from_file(
+                    str(new_path)
+                )
+            else:
+                return None
+
         source_size = ImageSize(source.get_width(), source.get_height())
         cover_size = ImageSize._make(shared.image_size)
 

cartridges/utils/save_cover.py

@@ -35,14 +35,6 @@ def convert_cover(
     if not cover_path and not pixbuf:
         return None
 
-    pixbuf_extensions = set()
-    for pixbuf_format in GdkPixbuf.Pixbuf.get_formats():
-        for pixbuf_extension in pixbuf_format.get_extensions():
-            pixbuf_extensions.add(pixbuf_extension)
-
-    if not resize and cover_path and cover_path.suffix.lower()[1:] in pixbuf_extensions:
-        return cover_path
-
     try:
         with Image.open(cover_path) as image:
             if getattr(image, "is_animated", False):