Fix for #812

cps/comic.py

@@ -24,21 +24,34 @@ import uploader
 
 
 def extractCover(tmp_file_name, original_file_extension):
+    cover_data = None
     if original_file_extension.upper() == '.CBZ':
         cf = zipfile.ZipFile(tmp_file_name)
-        compressed_name = cf.namelist()[0]
-        cover_data = cf.read(compressed_name)
+        for name in cf.namelist():
+            ext = os.path.splitext(name)
+            if len(ext) > 1:
+                extension = ext[1].lower()
+                if extension == '.jpg':
+                    cover_data = cf.read(name)
+                    break
     elif original_file_extension.upper() == '.CBT':
         cf = tarfile.TarFile(tmp_file_name)
-        compressed_name = cf.getnames()[0]
-        cover_data = cf.extractfile(compressed_name).read()
+        for name in cf.getnames():
+            ext = os.path.splitext(name)
+            if len(ext) > 1:
+                extension = ext[1].lower()
+                if extension == '.jpg':
+                    cover_data = cf.extractfile(name).read()
+                    break
 
     prefix = os.path.dirname(tmp_file_name)
-
-    tmp_cover_name = prefix + '/cover' + os.path.splitext(compressed_name)[1]
-    image = open(tmp_cover_name, 'wb')
-    image.write(cover_data)
-    image.close()
+    if cover_data:
+        tmp_cover_name = prefix + '/cover' + extension
+        image = open(tmp_cover_name, 'wb')
+        image.write(cover_data)
+        image.close()
+    else:
+        tmp_cover_name = None
     return tmp_cover_name