🚀 Support matching script and country code of locales with the text delegate

lib/src/delegates/asset_picker_text_delegate.dart

@@ -4,12 +4,12 @@
 
 import 'dart:io' show Platform;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:photo_manager/photo_manager.dart' show AssetType;
 
 /// All text delegates.
-const List<AssetPickerTextDelegate> assetPickerTextDelegates =
-    <AssetPickerTextDelegate>[
+const assetPickerTextDelegates = <AssetPickerTextDelegate>[
   AssetPickerTextDelegate(),
   EnglishAssetPickerTextDelegate(),
   HebrewAssetPickerTextDelegate(),
@@ -28,13 +28,30 @@ AssetPickerTextDelegate assetPickerTextDelegateFromLocale(Locale? locale) {
   if (locale == null) {
     return const AssetPickerTextDelegate();
   }
+
   final String languageCode = locale.languageCode.toLowerCase();
-  for (final AssetPickerTextDelegate delegate in assetPickerTextDelegates) {
-    if (delegate.languageCode == languageCode) {
-      return delegate;
-    }
+  final String? scriptCode = locale.scriptCode?.toLowerCase();
+  final String? countryCode = locale.countryCode?.toLowerCase();
+
+  final matchedByLanguage = assetPickerTextDelegates.where(
+    (e) => e.languageCode == languageCode,
+  );
+  if (matchedByLanguage.isEmpty) {
+    return const AssetPickerTextDelegate();
+  }
+
+  final matchedByScript = scriptCode != null
+      ? matchedByLanguage.where((e) => e.scriptCode == scriptCode)
+      : null;
+  if (matchedByScript == null || matchedByScript.isEmpty) {
+    return matchedByLanguage.first;
   }
-  return const AssetPickerTextDelegate();
+
+  final matchedByCountry = countryCode != null
+      ? matchedByScript.where((e) => e.countryCode == countryCode)
+      : null;
+
+  return matchedByCountry?.firstOrNull ?? matchedByScript.first;
 }
 
 /// Text delegate that controls text in widgets.
@@ -44,6 +61,17 @@ class AssetPickerTextDelegate {
 
   String get languageCode => 'zh';
 
+  String? get scriptCode => 'Hans';
+
+  String? get countryCode => null;
+
+  @nonVirtual
+  Locale get locale => Locale.fromSubtags(
+        languageCode: languageCode,
+        scriptCode: scriptCode,
+        countryCode: countryCode,
+      );
+
   /// Confirm string for the confirm button.
   /// 确认按钮的字段
   String get confirm => '确认';

test/delegates_test.dart

@@ -2,10 +2,40 @@
 // Use of this source code is governed by an Apache license that can be found
 // in the LICENSE file.
 
+import 'package:flutter/rendering.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:wechat_assets_picker/wechat_assets_picker.dart';
 
 void main() {
+  group(AssetPickerTextDelegate, () {
+    test('returns the default when available', () {
+      expect(
+        assetPickerTextDelegateFromLocale(null),
+        equals(const AssetPickerTextDelegate()),
+      );
+      expect(
+        assetPickerTextDelegateFromLocale(const Locale('zh')),
+        equals(const AssetPickerTextDelegate()),
+      );
+      expect(
+        assetPickerTextDelegateFromLocale(const Locale('zxx')),
+        equals(const AssetPickerTextDelegate()),
+      );
+    });
+
+    test('each delegate can be obtained by its locale definition', () {
+      for (final delegate in assetPickerTextDelegates) {
+        final locale = Locale.fromSubtags(
+          languageCode: delegate.languageCode,
+          scriptCode: delegate.scriptCode,
+          countryCode: delegate.countryCode,
+        );
+        final matchedDelegate = assetPickerTextDelegateFromLocale(locale);
+        expect(matchedDelegate, equals(delegate));
+      }
+    });
+  });
+
   test('Sort paths correctly', () {
     final List<PathWrapper<AssetPathEntity>> paths =
         <PathWrapper<AssetPathEntity>>[