feat: Add WebSocket support for real-time communication in NodeService

Author: AdamLBS

lib/services/node_service.dart

@@ -1,10 +1,13 @@
+import 'dart:async';
 import 'dart:convert';
 
 import 'package:flutter/foundation.dart';
 import 'package:hushnet_frontend/services/key_provider.dart';
 import 'package:hushnet_frontend/services/secure_storage_service.dart';
 import 'package:dio/dio.dart';
 import 'package:logging/logging.dart';
+import 'package:web_socket_channel/web_socket_channel.dart';
+import 'package:web_socket_channel/status.dart' as status;
 
 class NodeService {
   static final NodeService _instance = NodeService._internal();
@@ -16,6 +19,12 @@ class NodeService {
   final log = Logger('NodeService');
   final KeyProvider _keyProvider = KeyProvider();
 
+  WebSocketChannel? _channel;
+  StreamSubscription? _subscription;
+  String? _connectedUserId;
+  final _controller = StreamController<Map<String, dynamic>>.broadcast();
+
+  Stream<Map<String, dynamic>> get stream => _controller.stream;
 
 
 
@@ -72,6 +81,7 @@ class NodeService {
         await _storage.write('username', username);
         await _storage.write('user_id', userId);
         await _storage.write('node_url', nodeUrl);
+        await connectWebSocket(nodeUrl, userId);
         return username;
       } else {
         log.severe('Login failed: ${response.statusCode} ${response.data}');
@@ -117,7 +127,8 @@ class NodeService {
         final deviceKey = data['device_key'];
         await _storage.write('device_id', deviceId);
         await _storage.write('device_key', deviceKey);
-                stepNotifier?.value = 8;
+        await connectWebSocket(nodeUrl, userId);
+        stepNotifier?.value = 8;
 
         return true;
       } else {
@@ -140,5 +151,69 @@ class NodeService {
   Future<String?> getCurrentDeviceId() async {
     return await _storage.read('device_id');
   }
+Future<void> connectWebSocket(String nodeUrl, String userId) async {
+  if (_connectedUserId == userId && _channel != null) {
+    debugPrint("🔁 WebSocket already connected for $userId");
+    return;
+  }
+
+  var clean = nodeUrl.trim().replaceAll('#', '');
+  final parsed = Uri.parse(clean);
+
+  final scheme = (parsed.scheme == 'https' || parsed.scheme == 'wss')
+      ? 'wss'
+      : 'ws';
+
+  final host = parsed.host;
+  final port = parsed.hasPort ? ':${parsed.port}' : '';
+
+  final wsUrl = Uri.parse("$scheme://$host$port/ws/$userId");
+  debugPrint("Connecting WS to $wsUrl with $userId");
+
+  try {
+    _channel = WebSocketChannel.connect(wsUrl);
+    debugPrint("WS connected for $userId");
+    _connectedUserId = userId;
+
+    _subscription = _channel!.stream.listen(
+      (event) {
+        try {
+          final decoded = jsonDecode(event);
+          _controller.add(decoded);
+          debugPrint("WS event: $decoded");
+        } catch (e) {
+          debugPrint("Invalid WS payload: $e");
+        }
+      },
+      onError: (err) {
+        debugPrint("WS error: $err");
+        _retry(nodeUrl, userId);
+      },
+      onDone: () {
+        debugPrint("WS closed for $userId");
+        _retry(nodeUrl, userId);
+      },
+    );
+  } catch (e) {
+    debugPrint("Failed to connect WebSocket: $e");
+    _retry(nodeUrl, userId);
+  }
+}
+
+  void _retry(String nodeUrl, String userId) {
+    Future.delayed(const Duration(seconds: 3), () {
+      if (_connectedUserId == userId) {
+        connectWebSocket(nodeUrl, userId);
+      }
+    });
+  }
+
+  void disconnectWebSocket() {
+    //TODO : Implement disconnect logic
+    debugPrint("Closing WS connection...");
+    _subscription?.cancel();
+    _channel?.sink.close(status.normalClosure);
+    _connectedUserId = null;
+  }
 
 }

pubspec.lock

@@ -566,6 +566,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.1.1"
+  web_socket:
+    dependency: transitive
+    description:
+      name: web_socket
+      sha256: "34d64019aa8e36bf9842ac014bb5d2f5586ca73df5e4d9bf5c936975cae6982c"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.1"
+  web_socket_channel:
+    dependency: "direct main"
+    description:
+      name: web_socket_channel
+      sha256: d645757fb0f4773d602444000a8131ff5d48c9e47adfe9772652dd1a4f2d45c8
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.3"
   win32:
     dependency: transitive
     description:

pubspec.yaml

@@ -44,6 +44,7 @@ dependencies:
   cryptography: ^2.7.0
   intl: ^0.20.2
   uuid: ^4.5.1
+  web_socket_channel: ^3.0.3
 
 dependency_overrides:
   flutter_secure_storage_linux: