perfect: Built-in Perfect DB files for the first 8 moves

When enable Perfect DB, copy these files to strong dir.

src/ui/flutter_app/lib/general_settings/widgets/general_settings_page.dart

@@ -29,6 +29,7 @@ import '../../shared/config/constants.dart';
 import '../../shared/database/database.dart';
 import '../../shared/services/environment_config.dart';
 import '../../shared/services/logger.dart';
+import '../../shared/services/perfect_database_service.dart';
 import '../../shared/services/url.dart';
 import '../../shared/themes/app_theme.dart';
 import '../../shared/widgets/settings/settings.dart';
@@ -129,6 +130,10 @@ class GeneralSettingsPage extends StatelessWidget {
     DB().generalSettings = generalSettings.copyWith(usePerfectDatabase: value);
 
     logger.v("$_logTag usePerfectDatabase: $value");
+
+    if (value == true) {
+      copyPerfectDatabaseFiles();
+    }
   }
 
   void _showUsePerfectDatabaseDialog(BuildContext context) => showDialog(

src/ui/flutter_app/lib/shared/services/perfect_database_service.dart

@@ -0,0 +1,94 @@
+// This file is part of Sanmill.
+// Copyright (C) 2019-2024 The Sanmill developers (see AUTHORS file)
+//
+// Sanmill 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
+// (at your option) any later version.
+//
+// Sanmill 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 <http://www.gnu.org/licenses/>.
+
+import 'dart:io';
+import 'dart:typed_data';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+import 'package:path_provider/path_provider.dart';
+
+import 'logger.dart';
+
+Future<bool> copyPerfectDatabaseFiles() async {
+  Directory? dir;
+  try {
+    dir = (!kIsWeb && Platform.isAndroid)
+        ? await getExternalStorageDirectory()
+        : await getApplicationDocumentsDirectory();
+    logger.i('Directory obtained: ${dir?.path}');
+  } catch (e) {
+    logger.e('Failed to get directory: $e');
+    return false;
+  }
+
+  final String perfectDatabasePath = '${dir?.path}/strong';
+  final Directory directory = Directory(perfectDatabasePath);
+
+  try {
+    if (!await _exists(directory)) {
+      await directory.create(recursive: true);
+      logger.i('Created directory at $perfectDatabasePath');
+    }
+  } catch (e) {
+    logger.e('Error creating directory $perfectDatabasePath: $e');
+    return false;
+  }
+
+  // List of asset files to copy
+  final List<String> assetFiles = <String>[
+    'assets/databases/std.secval',
+    'assets/databases/std_0_0_9_9.sec2',
+    'assets/databases/std_0_1_9_8.sec2',
+    'assets/databases/std_1_1_8_8.sec2',
+    'assets/databases/std_1_2_8_7.sec2',
+    'assets/databases/std_1_3_7_6.sec2',
+    'assets/databases/std_2_2_7_7.sec2',
+    'assets/databases/std_2_3_6_6.sec2',
+    'assets/databases/std_2_3_7_6.sec2',
+    'assets/databases/std_2_4_6_5.sec2',
+    'assets/databases/std_3_3_5_5.sec2',
+    'assets/databases/std_3_3_6_5.sec2',
+    'assets/databases/std_3_3_6_6.sec2',
+    'assets/databases/std_3_4_5_5.sec2',
+    'assets/databases/std_3_4_6_5.sec2',
+    'assets/databases/std_4_3_5_5.sec2',
+    'assets/databases/std_4_4_5_5.sec2'
+  ];
+
+  for (final String asset in assetFiles) {
+    try {
+      final File file = File('${directory.path}/${asset.split('/').last}');
+      if (!await _exists(file)) {
+        final ByteData byteData = await rootBundle.load(asset);
+        final ByteBuffer buffer = byteData.buffer;
+        await file.writeAsBytes(
+            buffer.asUint8List(byteData.offsetInBytes, byteData.lengthInBytes));
+        logger.i('Copied file to ${file.path}');
+      } else {
+        logger.i('File already exists and was not overwritten: ${file.path}');
+      }
+    } catch (e) {
+      logger.e('Failed to copy asset $asset: $e');
+      return false;
+    }
+  }
+
+  return true;
+}
+
+Future<bool> _exists(FileSystemEntity entity) async {
+  return entity.exists();
+}

src/ui/flutter_app/pubspec.yaml

@@ -104,6 +104,23 @@ flutter:
     - assets/images/background_image_3.jpg
     - assets/images/background_image_4.jpg
     - assets/images/background_image_5.jpg
+    - assets/databases/std.secval
+    - assets/databases/std_0_0_9_9.sec2
+    - assets/databases/std_0_1_9_8.sec2
+    - assets/databases/std_1_1_8_8.sec2
+    - assets/databases/std_1_2_8_7.sec2
+    - assets/databases/std_1_3_7_6.sec2
+    - assets/databases/std_2_2_7_7.sec2
+    - assets/databases/std_2_3_6_6.sec2
+    - assets/databases/std_2_3_7_6.sec2
+    - assets/databases/std_2_4_6_5.sec2
+    - assets/databases/std_3_3_5_5.sec2
+    - assets/databases/std_3_3_6_5.sec2
+    - assets/databases/std_3_3_6_6.sec2
+    - assets/databases/std_3_4_5_5.sec2
+    - assets/databases/std_3_4_6_5.sec2
+    - assets/databases/std_4_3_5_5.sec2
+    - assets/databases/std_4_4_5_5.sec2
 
 flutter_intl:
   enabled: true