feat(i18n): add i18n delegate + example

packages/wyatt_i18n/lib/src/core/core.dart

@@ -16,4 +16,5 @@
 
 export 'enums/format.dart';
 export 'exceptions/exceptions.dart';
+export 'extensions/build_context_extension.dart';
 export 'utils/utils.dart';

packages/wyatt_i18n/lib/src/core/extensions/build_context_extension.dart

@@ -0,0 +1,36 @@
+// Copyright (C) 2023 WYATT GROUP
+// Please see the AUTHORS file for details.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+import 'package:flutter/widgets.dart';
+import 'package:wyatt_i18n/wyatt_i18n.dart';
+
+/// Provides extensions for [BuildContext].
+extension BuildContextExtension on BuildContext {
+  /// Returns the current locale of the app.
+  String get locale => Localizations.localeOf(this).languageCode;
+
+  /// Returns the current [I18n] instance.
+  ///
+  /// Throws a [NotLoadedException] if the [I18n] instance is not loaded.
+  I18n get i18n {
+    final i18n = Localizations.of<I18n>(this, I18n);
+    if (i18n == null) {
+      throw NotLoadedException();
+    }
+
+    return i18n;
+  }
+}

packages/wyatt_i18n/lib/src/presentation/i18n_delegate.dart

@@ -0,0 +1,51 @@
+// Copyright (C) 2023 WYATT GROUP
+// Please see the AUTHORS file for details.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+import 'package:flutter/cupertino.dart';
+import 'package:wyatt_i18n/wyatt_i18n.dart';
+
+/// {@template i18n_delegate}
+/// A [LocalizationsDelegate] that loads the [I18n] instance.
+/// {@endtemplate}
+class I18nDelegate extends LocalizationsDelegate<I18n> {
+  /// {@macro i18n_delegate}
+  I18nDelegate({
+    required this.repository,
+  });
+
+  /// The [I18nRepository] that will be used to load the i18n file.
+  final I18nRepository repository;
+
+  /// The current locale.
+  Locale? currentLocale;
+
+  /// Since we are using the [I18nRepository] to load the i18n file,
+  /// we don't need to check if the locale is supported.
+  /// We can just return `true`.
+  @override
+  bool isSupported(Locale locale) => true;
+
+  @override
+  Future<I18n> load(Locale locale) async {
+    await repository.load(locale: locale.languageCode);
+
+    return I18n(i18nRepository: repository);
+  }
+
+  @override
+  bool shouldReload(I18nDelegate old) =>
+      currentLocale != null || currentLocale != old.currentLocale;
+}

packages/wyatt_i18n/lib/src/src.dart

@@ -17,3 +17,4 @@
 export 'core/core.dart';
 export 'data/data.dart';
 export 'domain/domain.dart';
+export 'presentation/i18n_delegate.dart';