FEATURE: Add user interface translation support (internationalization)

Add scripts to create and update translations
Allow UI language to be defined as a command line argument

MethodicConfigurator/ardupilot_methodic_configurator.py

@@ -32,9 +32,9 @@
 
 from MethodicConfigurator.frontend_tkinter_parameter_editor import ParameterEditorWindow
 
-from MethodicConfigurator.common_arguments import add_common_arguments_and_parse
+from MethodicConfigurator.common_arguments import add_common_arguments_and_parse, LANGUAGE_CHOICES
 
-from MethodicConfigurator.internationalization import _
+from MethodicConfigurator.internationalization import _, load_translation
 
 from MethodicConfigurator.version import VERSION
 
@@ -117,6 +117,7 @@ def component_editor(args, flight_controller, vehicle_type, local_filesystem, ve
 
 
 def main():
+    load_translation()
     args = argument_parser()
 
     logging_basicConfig(level=logging_getLevelName(args.loglevel), format='%(asctime)s - %(levelname)s - %(message)s')

MethodicConfigurator/common_arguments.py

@@ -9,16 +9,23 @@
 '''
 
 from MethodicConfigurator.version import VERSION
-from MethodicConfigurator.internationalization import _
+
+from MethodicConfigurator.internationalization import _, LANGUAGE_CHOICES
+
 
 def add_common_arguments_and_parse(parser):
     parser.add_argument('--loglevel',
                         type=str,
                         default='INFO',
                         choices=['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'],
-                        help=_('Logging level (default is INFO).'))
+                        help=_('Logging level (default is %(default)s).'))
     parser.add_argument('-v', '--version',
                         action='version',
                         version=f'%(prog)s {VERSION}',
                         help=_('Display version information and exit.'))
+    parser.add_argument('--language',
+                        type=str,
+                        default='en',
+                        choices=LANGUAGE_CHOICES,
+                        help=_('User interface language (default is %(default)s).'))
     return parser.parse_args()

MethodicConfigurator/internationalization.py

@@ -8,15 +8,35 @@
 SPDX-License-Identifier: GPL-3.0-or-later
 '''
 
+import argparse
 import gettext
 
+LANGUAGE_CHOICES = ['en']
 
-# Setup language
-locale_path = 'locale'  # directory of locale file
-language = 'zh_CN'  # select language
 
-# create translation
-translation = gettext.translation('messages', localedir=locale_path, languages=[language], fallback=True)
+def identity_function(s):
+    return s
 
-# set translation object as _()
-_ = translation.gettext
+
+def load_translation() -> None:
+    # First, pre-parse to find the --language argument
+    pre_parser = argparse.ArgumentParser(add_help=False)
+    pre_parser.add_argument('--language', type=str, default='en', choices=LANGUAGE_CHOICES)
+    pre_args, _list_str = pre_parser.parse_known_args()
+
+    # modify the global _() function
+    global _  # pylint: disable=global-statement
+
+    # Load the correct language ASAP based on the command line argument
+    try:
+        translation = gettext.translation('MethodicConfigurator', localedir='locale',
+                                          languages=[pre_args.language], fallback=False)
+        _ = translation.gettext
+    except FileNotFoundError:
+        _ = identity_function  # Return identity function
+        print(_("Translation files not found for the selected language. Falling back to default."))
+
+
+# Default to identity function if _ is not already defined
+if '_' not in globals():
+    _ = identity_function