import 'dart:async';
import 'dart:ui' as ui;

import 'package:flutter/material.dart';

import 'package:yumi/app/constants/sc_global_config.dart';
import 'package:yumi/app_localizations.dart';
import 'package:yumi/shared/data_sources/sources/local/data_persistence.dart';

class LocalizationManager with ChangeNotifier {
  Locale? _locale;

  Locale? get locale => _locale;

  LocalizationManager() {
    _locale = _resolveInitialLocale();
    if (_locale != null) {
      SCGlobalConfig.lang = _locale!.languageCode;
    }
  }

  Locale _resolveInitialLocale() {
    final language = DataPersistence.getLang();
    if (language.isEmpty) {
      final systemLocale = ui.PlatformDispatcher.instance.locale;
      return _localeFromLanguageCode(systemLocale.languageCode);
    }
    return _localeFromLanguageCode(language);
  }

  Locale _localeFromLanguageCode(String languageCode) {
    return Locale(
      SCAppLocalizations.resolveSupportedLanguageCode(languageCode),
      '',
    );
  }

  void changeAppLanguage(Locale locale) {
    if (_locale?.languageCode == locale.languageCode &&
        _locale?.countryCode == locale.countryCode) {
      return;
    }
    _locale = _localeFromLanguageCode(locale.languageCode);
    SCGlobalConfig.lang = _locale!.languageCode;
    unawaited(DataPersistence.setLang(_locale!.languageCode));
    notifyListeners();
  }
}