Craft Launcher Core

A Dart package for launching Minecraft Java Edition. This library simplifies the process of managing launcher profiles, downloading game assets, and starting Minecraft instances.

Features

• Minecraft version management
• Game assets and libraries downloading
• Java runtime detection and management
• Profile configuration and customization
• Launch with Microsoft authentication support
• Extensible launcher adapter system
• Customizable launcher branding

Getting started

Add this package to your pubspec.yaml:

dependencies:
  craft_launcher_core: ^0.0.3

Then run:

flutter pub get

Usage

Basic Launcher Setup

import 'package:craft_launcher_core/vanilla_launcher.dart';
import 'package:craft_launcher_core/models/launcher_profiles.dart';

// Create a profile
final myProfile = Profile(
  icon: 'minecraft',
  name: 'MyProfile',
  type: 'latest-release',
  created: DateTime.now().toIso8601String(),
  lastUsed: DateTime.now().toIso8601String(),
  lastVersionId: '1.21.3',
);

// Initialize launcher
final launcher = VanillaLauncher(
  gameDir: '/path/to/minecraft',
  javaDir: '/path/to/java',
  profiles: LauncherProfiles(
    profiles: {'my_profile': myProfile},
    settings: Settings(
      enableSnapshots: false,
      keepLauncherOpen: true,
      showGameLog: true,
    ),
    version: 3,
  ),
  activeProfile: myProfile,
  onOperationProgress: (operation, completed, total, percentage) {
    print('$operation: $percentage%');
  },
  launcherName: 'MyCustomLauncher',
  launcherVersion: '2.0.0',
);

// Launch the game
await launcher.launch(
  onStdout: (data) => print('Minecraft: $data'),
  onStderr: (data) => print('Error: $data'),
  onExit: (code) => print('Game exited with code: $code'),
);

Using with Microsoft Authentication

import 'package:craft_launcher_core/vanilla_launcher.dart';
import 'package:craft_launcher_core/models/models.dart';
import 'package:mcid_connect/mcid_connect.dart';

// Authenticate with Microsoft (see mcid_connect package)
final authService = AuthService(
  clientId: 'your-azure-app-client-id',
  redirectUri: 'http://localhost:3000',
  scopes: ['XboxLive.signin', 'offline_access'],
  onGetDeviceCode: (deviceCodeResponse) {
    print('Please visit: ${deviceCodeResponse.verificationUri}');
    print('And enter this code: ${deviceCodeResponse.userCode}');
  },
);

await authService.startAuthenticationFlow();

// Initialize the launcher with auth
final launcher = VanillaLauncher(
  // Game directory settings
  gameDir: '/path/to/minecraft',
  javaDir: '/path/to/java',
  profiles: myProfiles,
  activeProfile: myProfile,
  
  // Authentication data from Microsoft login
  minecraftAuth: MinecraftAuth(
    clientId: 'your-azure-app-client-id',
    authXuid: authService.xstsUhs,
    userName: authService.minecraftProfile.name,
    uuid: authService.minecraftProfile.id,
    accessToken: authService.minecraftToken,
    userType: 'msa',
  ),
  
  launcherName: 'MyAuthenticatedLauncher',
  launcherVersion: '1.5.2',
);

// Launch with authentication
await launcher.launch();

Creating a Custom Launcher Adapter

import 'package:craft_launcher_core/vanilla_launcher.dart';
import 'package:craft_launcher_core/launcher_adapter.dart';
import 'package:craft_launcher_core/models/models.dart';

class ModdedLauncherAdapter implements LauncherAdapter {
  final LauncherAdapter _vanillaAdapter;
  
  ModdedLauncherAdapter(this._vanillaAdapter);
  
  @override
  Future<void> afterBuildClasspath(
    VersionInfo versionInfo, 
    String versionId, 
    List<String> classpath,
  ) async {
    // Add mod loaders to classpath
    classpath.add('/path/to/forge.jar');
    
    // Continue with vanilla behavior
    await _vanillaAdapter.afterBuildClasspath(versionInfo, versionId, classpath);
  }
  
  // Implement other interface methods or delegate to vanilla adapter
  @override
  Future<void> beforeStartProcess(
    String javaExe,
    List<String> javaArgs,
    String workingDirectory,
    Map<String, String> environment,
    String versionId,
    MinecraftAuth? auth,
  ) async {
    // Add custom JVM arguments
    javaArgs.add('-Dfml.ignoreInvalidMinecraftCertificates=true');
    javaArgs.add('-Dfml.ignorePatchDiscrepancies=true');
    
    // Setup mod-specific environment variables
    environment['FORGE_LOGGING_MARKERS'] = 'SCAN,REGISTRIES,REGISTRYDUMP';
    
    // Continue with vanilla behavior
    await _vanillaAdapter.beforeStartProcess(
      javaExe, javaArgs, workingDirectory, environment, versionId, auth,
    );
  }
  
  @override
  Future<void> afterStartProcess(
    String versionId,
    MinecraftProcessInfo processInfo,
    MinecraftAuth? auth,
  ) async {
    // Do post-process operations like starting a mod server or logging
    print('Modded Minecraft started with PID: ${processInfo.pid}');
    
    // Continue with vanilla behavior if needed
    await _vanillaAdapter.afterStartProcess(versionId, processInfo, auth);
  }
  
  // Implement other hooks as needed to customize the launch process
  @override
  Future<void> beforeDownloadAssets(String versionId) async {
    print('Preparing to download assets for modded Minecraft $versionId');
    await _vanillaAdapter.beforeDownloadAssets(versionId);
  }
}

// Using the custom adapter with a vanilla launcher
final vanillaLauncher = VanillaLauncher(
  gameDir: '/path/to/minecraft',
  javaDir: '/path/to/java',
  profiles: myProfiles,
  activeProfile: myProfile,
  // Other configuration...
);

// Wrap the vanilla launcher with your custom adapter
final moddedAdapter = ModdedLauncherAdapter(vanillaLauncher);

// Launch using the modded adapter
// Note: you still use the vanilla launcher's launch method
// but the adapter hooks will be called during the process
await vanillaLauncher.launch();

Additional information

Requirements

• Dart SDK 3.7.2 or higher
• Java Runtime Environment (JRE) or Java Development Kit (JDK) for running Minecraft
• Internet connection for downloading game assets and libraries

Customization Options

• Launcher Branding: Customize the launcher name and version that appears in Minecraft by setting the launcherName and launcherVersion parameters in the VanillaLauncher constructor. If not specified, the default values "CraftLauncher" and "1.0.0" will be used.

Contributing

Contributions are welcome! Feel free to submit issues or pull requests on the GitHub repository.

License

This package is available under the MIT License.