tor lifecycle management

app/lib/features/tor/utils/tor_entrypoint.dart

@@ -1,22 +1,50 @@
+import 'dart:async';
+
 import 'package:flutter_background_service/flutter_background_service.dart';
 import 'package:tor/tor.dart';
 
 @pragma('vm:entry-point')
 Future<void> onStart(ServiceInstance service) async {
+  Timer? timeout;
+
   await Tor.init();
 
   final portSub = Tor.instance.events.stream.listen((port) {
     service.invoke('portUpdate', {'port': port});
   });
 
-  await Tor.instance.start();
+  Future<void> stopService() async {
+    timeout?.cancel();
+    timeout = null;
 
-  service.on("stop").listen((event) async {
     Tor.instance.stop();
     service.invoke('portUpdate', {'port': -1});
 
     await portSub.cancel();
 
     await service.stopSelf();
+  }
+
+  void addHeartbeat() {
+    timeout?.cancel();
+    timeout = Timer(const Duration(minutes: 15), () async {
+      // logger.i('Terminating tor due to timeout');
+      await stopService();
+    });
+  }
+
+  await Tor.instance.start();
+
+  service.on("heartbeat").listen((event) {
+    // logger.d('Received tor heartbeat');
+    addHeartbeat();
+  });
+
+  service.on("sync").listen((event) {
+    service.invoke('portUpdate', {'port': Tor.instance.port});
+  });
+
+  service.on("stop").listen((event) async {
+    await stopService();
   });
 }