umbrix/lib/main.dart

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:umbrix/bootstrap.dart';
import 'package:umbrix/core/model/environment.dart';

final lockFile = File('/tmp/umbrix.lock');

Future<void> _activateExistingWindow() async {
  // Try to activate existing window via wmctrl
  try {
    final result = await Process.run('wmctrl', ['-a', 'Umbrix']);
    if (result.exitCode == 0) return;
  } catch (e) {
    // wmctrl not available, try xdotool
    try {
      await Process.run('xdotool', ['search', '--name', 'Umbrix', 'windowactivate']);
    } catch (e) {
      // No window activation possible
    }
  }
}

void _cleanupLockFile() {
  try {
    if (lockFile.existsSync()) {
      lockFile.deleteSync();
    }
  } catch (e) {
    // Ignore cleanup errors
  }
}

void main() async {
  // Single instance check - BEFORE Flutter initialization
  if (Platform.isLinux || Platform.isWindows) {
    if (await lockFile.exists()) {
      // Check if process is still alive
      try {
        final pidString = await lockFile.readAsString();
        final pid = int.tryParse(pidString.trim());
        if (pid != null) {
          final result = await Process.run('ps', ['-p', pid.toString()]);
          if (result.exitCode != 0) {
            // Process dead, remove stale lock
            await lockFile.delete();
          } else {
            // Process alive - activate window and exit
            await _activateExistingWindow();
            exit(0);
          }
        }
      } catch (e) {
        // Error reading lock, remove it
        try { await lockFile.delete(); } catch (e) {}
      }
    }
    
    // Create lock file
    try {
      await lockFile.create();
      await lockFile.writeAsString(pid.toString());
    } catch (e) {
      // If can't create, continue anyway
    }
  }

  final widgetsBinding = WidgetsFlutterBinding.ensureInitialized();

  SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
  SystemChrome.setSystemUIOverlayStyle(
    const SystemUiOverlayStyle(
      statusBarColor: Colors.transparent,
      systemNavigationBarColor: Colors.transparent,
    ),
  );

  return lazyBootstrap(widgetsBinding, Environment.dev);
}