sgf arg fix

katrain/__main__.py

@@ -157,8 +157,13 @@ class KaTrainGui(Screen, KaTrainBase):
         self.board_gui.trainer_config = self.config("trainer")
         self.engine = KataGoEngine(self, self.config("engine"))
         threading.Thread(target=self._message_loop_thread, daemon=True).start()
-        if len(sys.argv) == 2 and os.path.isfile(sys.argv[1]) and not sys.argv[1].endswith('json'):
-            self.load_sgf_file(sys.argv[1], fast=True, rewind=True)
+        sgf_args = [
+            f
+            for f in sys.argv[1:]
+            if os.path.isfile(f) and any(f.lower().endswith(ext) for ext in ["sgf", "ngf", "gib"])
+        ]
+        if sgf_args:
+            self.load_sgf_file(sgf_args[0], fast=True, rewind=True)
         else:
             self._do_new_game()