lib/main/adapter/gateway/installation_file_storage.dart

@@ -2,4 +2,6 @@ import 'dart:typed_data';
 
 abstract interface class InstallationFileStorage {
   Future<void> saveFile(Uint8List fileBytes, String path);
+
+  Future<void> writeFile(String path, String content);
 }

lib/main/adapter/gateway/installation_repository_impl.dart

@@ -9,8 +9,11 @@ class InstallationRepositoryImpl implements InstallationRepository {
   InstallationRepositoryImpl(this._apiService, this._fileStorage);
 
   @override
-  Future<void> downloadServerFile(Uri url, String path, {DownloadProgressCallback? onProgressChanged}) async {
+  Future<void> downloadFile(Uri url, String path, {DownloadProgressCallback? onProgressChanged}) async {
     final fileBytes = await _apiService.fetchRemoteFile(url, onProgressChanged: onProgressChanged);
     await _fileStorage.saveFile(fileBytes, path);
   }
+
+  @override
+  Future<void> writeFile(String path, String content) => _fileStorage.writeFile(path, content);
 }

lib/main/adapter/presentation/installation_bloc.dart

@@ -2,12 +2,16 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:minecraft_server_installer/main/adapter/presentation/installation_state.dart';
 import 'package:minecraft_server_installer/main/adapter/presentation/progress_view_model.dart';
 import 'package:minecraft_server_installer/main/application/use_case/download_file_use_case.dart';
+import 'package:minecraft_server_installer/main/application/use_case/write_file_use_case.dart';
 import 'package:minecraft_server_installer/main/constants.dart';
 import 'package:minecraft_server_installer/vanilla/adapter/presentation/game_version_view_model.dart';
 import 'package:path/path.dart' as path;
 
 class InstallationBloc extends Bloc<InstallationEvent, InstallationState> {
-  InstallationBloc(DownloadFileUseCase downloadFileUseCase) : super(const InstallationState.empty()) {
+  InstallationBloc(
+    DownloadFileUseCase downloadFileUseCase,
+    WriteFileUseCase writeFileUseCase,
+  ) : super(const InstallationState.empty()) {
     on<InstallationStartedEvent>((_, emit) async {
       if (!state.canStartToInstall) {
         return;
@@ -24,6 +28,11 @@ class InstallationBloc extends Bloc<InstallationEvent, InstallationState> {
         onProgressChanged: (progressValue) => add(_InstallationProgressValueChangedEvent(progressValue)),
       );
 
+      await writeFileUseCase(
+        path.join(savePath, Constants.startScriptFileName),
+        'java -jar ${Constants.serverFileName}\n',
+      );
+
       emit(state.copyWith(isLocked: false, downloadProgress: const ProgressViewModel.complete()));
     });
 

lib/main/application/repository/installation_repository.dart

@@ -1,5 +1,7 @@
 typedef DownloadProgressCallback = void Function(double progress);
 
 abstract interface class InstallationRepository {
-  Future<void> downloadServerFile(Uri url, String path, {DownloadProgressCallback? onProgressChanged});
+  Future<void> downloadFile(Uri url, String path, {DownloadProgressCallback? onProgressChanged});
+
+  Future<void> writeFile(String path, String content);
 }

lib/main/application/use_case/download_file_use_case.dart

@@ -6,5 +6,5 @@ class DownloadFileUseCase {
   DownloadFileUseCase(this._installationRepository);
 
   Future<void> call(Uri url, String path, {DownloadProgressCallback? onProgressChanged}) =>
-      _installationRepository.downloadServerFile(url, path, onProgressChanged: onProgressChanged);
+      _installationRepository.downloadFile(url, path, onProgressChanged: onProgressChanged);
 }

lib/main/application/use_case/write_file_use_case.dart

@@ -0,0 +1,9 @@
+import 'package:minecraft_server_installer/main/application/repository/installation_repository.dart';
+
+class WriteFileUseCase {
+  final InstallationRepository _installationRepository;
+
+  WriteFileUseCase(this._installationRepository);
+
+  Future<void> call(String path, String content) => _installationRepository.writeFile(path, content);
+}

lib/main/constants.dart

@@ -1,4 +1,8 @@
+import 'dart:io';
+
 abstract class Constants {
   static const gameVersionListUrl = 'https://www.dropbox.com/s/mtz3moc9dpjtz7s/GameVersions.txt?dl=1';
   static const serverFileName = 'server.jar';
+
+  static final startScriptFileName = Platform.isWindows ? 'start.bat' : 'start.sh';
 }

lib/main/framework/storage/installation_file_storage_impl.dart

@@ -7,12 +7,14 @@ class InstallationFileStorageImpl implements InstallationFileStorage {
   @override
   Future<void> saveFile(Uint8List fileBytes, String path) async {
     final file = File(path);
-
+    await file.create(recursive: true, exclusive: false);
-    if (!await file.parent.exists()) {
-      await file.parent.create(recursive: true);
-    }
-
-    await file.create();
     await file.writeAsBytes(fileBytes, flush: true);
   }
+
+  @override
+  Future<void> writeFile(String path, String content) async {
+    File file = File(path);
+    await file.create(recursive: true, exclusive: false);
+    await file.writeAsString(content, flush: true);
+  }
 }

lib/main/framework/ui/minecraft_server_installer.dart

@@ -4,6 +4,7 @@ import 'package:minecraft_server_installer/main/adapter/gateway/installation_rep
 import 'package:minecraft_server_installer/main/adapter/presentation/installation_bloc.dart';
 import 'package:minecraft_server_installer/main/adapter/presentation/installation_state.dart';
 import 'package:minecraft_server_installer/main/application/use_case/download_file_use_case.dart';
+import 'package:minecraft_server_installer/main/application/use_case/write_file_use_case.dart';
 import 'package:minecraft_server_installer/main/framework/api/installation_api_service_impl.dart';
 import 'package:minecraft_server_installer/main/framework/storage/installation_file_storage_impl.dart';
 import 'package:minecraft_server_installer/main/framework/ui/basic_configuration_tab.dart';
@@ -28,6 +29,7 @@ class MinecraftServerInstaller extends StatelessWidget {
     final gameVersionRepository = VanillaRepositoryImpl(gameVersionApiService);
 
     final downloadFileUseCase = DownloadFileUseCase(installationRepository);
+    final writeFileUseCase = WriteFileUseCase(installationRepository);
     final getGameVersionListUseCase = GetGameVersionListUseCase(gameVersionRepository);
 
     return MaterialApp(
@@ -35,7 +37,7 @@ class MinecraftServerInstaller extends StatelessWidget {
       theme: ThemeData.light().copyWith(colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue.shade900)),
       home: MultiBlocProvider(
         providers: [
-          BlocProvider(create: (_) => InstallationBloc(downloadFileUseCase)),
+          BlocProvider(create: (_) => InstallationBloc(downloadFileUseCase, writeFileUseCase)),
           BlocProvider<VanillaBloc>(
             create: (_) => VanillaBloc(getGameVersionListUseCase)..add(VanillaGameVersionListLoadedEvent()),
           ),