Files
meshcore-sar_android/lib/services/sse_client_service.dart
2026-02-28 10:11:33 +01:00

626 lines
21 KiB
Dart

import 'dart:async';
import 'dart:convert';
import 'dart:io' as io;
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;
import 'package:http/io_client.dart' as io_client;
import '../models/message.dart';
import '../models/contact.dart';
import 'package:latlong2/latlong.dart';
/// SSE Client Service
///
/// Connects to a remote SSE server to receive messages and contacts in real-time.
/// This enables multiple app instances to share a single MeshCore BLE device
/// without direct BLE connections.
class SseClientService {
String? _serverUrl;
String? _authToken;
http.Client? _httpClient;
StreamSubscription? _messageSubscription;
StreamSubscription? _contactSubscription;
bool _isConnected = false;
bool _isConnecting = false;
bool _hasConnectedBefore = false; // Track if we've ever successfully connected
Timer? _reconnectTimer;
Timer? _heartbeatTimer;
int _reconnectAttempts = 0;
static const int _maxReconnectAttempts = 10;
static const Duration _reconnectDelay = Duration(seconds: 5);
/// Callback for when a message is received
Function(Message)? onMessageReceived;
/// Callback for when a contact is received
Function(Contact)? onContactReceived;
/// Callback for connection state changes
Function(bool isConnected)? onConnectionStateChanged;
/// Callback for errors
Function(String error)? onError;
/// Check if client is connected
bool get isConnected => _isConnected;
/// Check if client is currently connecting
bool get isConnecting => _isConnecting;
/// Get current reconnection attempt number
int get reconnectionAttempts => _reconnectAttempts;
/// Get maximum reconnection attempts
int get maxReconnectionAttempts => _maxReconnectAttempts;
/// Get server URL
String? get serverUrl => _serverUrl;
/// Connect to SSE server
Future<void> connect({
required String serverUrl,
String? authToken,
}) async {
if (_isConnected) {
debugPrint('⚠️ [SseClient] Already connected');
return;
}
_serverUrl = serverUrl;
_authToken = authToken;
_isConnecting = true;
debugPrint('🔌 [SseClient] Connecting to $serverUrl (attempt ${_reconnectAttempts + 1}/$_maxReconnectAttempts)');
try {
// Create a new HTTP client with custom configuration for SSE streaming
// Using IOClient with custom HttpClient for better control over connection settings
final ioHttpClient = io.HttpClient();
ioHttpClient.connectionTimeout = const Duration(seconds: 10);
ioHttpClient.idleTimeout = const Duration(hours: 1); // Keep SSE connections alive
_httpClient = io_client.IOClient(ioHttpClient);
// Test server availability
await _checkServerStatus();
// Fetch initial message history
await _fetchMessageHistory();
// Fetch initial contact list
await _fetchContacts();
// Subscribe to SSE streams
debugPrint('🔗 [SseClient] Subscribing to message stream...');
debugPrint('🔗 [SseClient] Using HTTP client type: ${_httpClient.runtimeType}');
await _subscribeToMessages();
debugPrint('🔗 [SseClient] Subscribing to contact stream...');
await _subscribeToContacts();
debugPrint('🔗 [SseClient] All subscriptions complete');
_isConnected = true;
_isConnecting = false;
_hasConnectedBefore = true; // Mark that we've successfully connected
_reconnectAttempts = 0;
debugPrint('🔔 [SseClient] Calling onConnectionStateChanged(true)');
onConnectionStateChanged?.call(true);
// Start heartbeat to detect connection loss
_startHeartbeat();
debugPrint('✅ [SseClient] Connected successfully');
} catch (e) {
_isConnecting = false;
_httpClient?.close();
_httpClient = null;
debugPrint('❌ [SseClient] Connection failed: $e');
onError?.call('Connection failed: $e');
// Only auto-reconnect if we've successfully connected before
// Initial connection failures should be handled by the user
if (_hasConnectedBefore) {
_scheduleReconnect();
}
}
}
/// Disconnect from SSE server
Future<void> disconnect() async {
debugPrint('🔌 [SseClient] Disconnecting...');
_isConnected = false;
_isConnecting = false;
_hasConnectedBefore = false; // Reset on manual disconnect
_reconnectTimer?.cancel();
_heartbeatTimer?.cancel();
await _messageSubscription?.cancel();
await _contactSubscription?.cancel();
_httpClient?.close();
_serverUrl = null;
_authToken = null;
_httpClient = null;
onConnectionStateChanged?.call(false);
debugPrint('✅ [SseClient] Disconnected');
}
/// Check server status
Future<void> _checkServerStatus() async {
final url = Uri.parse('$_serverUrl/api/status');
try {
final response = await http.get(url, headers: _getHeaders()).timeout(
const Duration(seconds: 5),
);
if (response.statusCode != 200) {
throw Exception('Server returned ${response.statusCode}');
}
final data = jsonDecode(response.body);
debugPrint('📊 [SseClient] Server status: ${data['status']}');
debugPrint(' Connected clients: ${data['connectedClients']}');
debugPrint(' Messages: ${data['messageCount']}');
debugPrint(' Contacts: ${data['contactCount']}');
} catch (e) {
// Wrap the error with more user-friendly message
throw Exception(_formatConnectionError(e));
}
}
/// Format connection error to be more user-friendly
String _formatConnectionError(dynamic error) {
final errorStr = error.toString();
// Extract the actual server URL being connected to
final serverUri = Uri.tryParse(_serverUrl ?? '');
final host = serverUri?.host ?? 'unknown';
final port = serverUri?.port ?? 0;
if (errorStr.contains('Connection refused')) {
return 'Server not available at $host:$port. The server may be offline or not running.';
} else if (errorStr.contains('TimeoutException') || errorStr.contains('timed out')) {
return 'Connection to $host:$port timed out. Check your network connection.';
} else if (errorStr.contains('SocketException')) {
return 'Network error connecting to $host:$port. Check your network connection.';
} else if (errorStr.contains('Failed host lookup')) {
return 'Could not resolve hostname: $host';
}
// Return the original error if we can't make it more user-friendly
return errorStr;
}
/// Fetch message history on connect
Future<void> _fetchMessageHistory() async {
try {
final url = Uri.parse('$_serverUrl/api/messages/history');
final response = await http.get(url, headers: _getHeaders()).timeout(
const Duration(seconds: 10),
);
if (response.statusCode != 200) {
throw Exception('Failed to fetch message history: ${response.statusCode}');
}
final data = jsonDecode(response.body) as Map<String, dynamic>;
final messages = data['messages'] as List;
debugPrint('📥 [SseClient] Received ${messages.length} messages from history');
for (final msgJson in messages) {
try {
final message = _messageFromJson(msgJson);
onMessageReceived?.call(message);
} catch (e) {
debugPrint('⚠️ [SseClient] Failed to parse message: $e');
}
}
} catch (e) {
debugPrint('❌ [SseClient] Error fetching message history: $e');
// Don't throw - continue with connection even if history fetch fails
}
}
/// Fetch contacts on connect
Future<void> _fetchContacts() async {
try {
final url = Uri.parse('$_serverUrl/api/contacts');
final response = await http.get(url, headers: _getHeaders()).timeout(
const Duration(seconds: 10),
);
if (response.statusCode != 200) {
throw Exception('Failed to fetch contacts: ${response.statusCode}');
}
final data = jsonDecode(response.body) as Map<String, dynamic>;
final contacts = data['contacts'] as List;
debugPrint('📥 [SseClient] Received ${contacts.length} contacts');
for (final contactJson in contacts) {
try {
final contact = _contactFromJson(contactJson);
onContactReceived?.call(contact);
} catch (e) {
debugPrint('⚠️ [SseClient] Failed to parse contact: $e');
}
}
} catch (e) {
debugPrint('❌ [SseClient] Error fetching contacts: $e');
// Don't throw - continue with connection even if contacts fetch fails
}
}
/// Subscribe to SSE message stream
Future<void> _subscribeToMessages() async {
try {
if (_httpClient == null) {
throw Exception('HTTP client not initialized');
}
debugPrint('📡 [SseClient] Creating message stream request...');
final url = Uri.parse('$_serverUrl/sse/messages');
final request = http.Request('GET', url);
request.headers.addAll(_getHeaders());
request.headers['Accept'] = 'text/event-stream';
request.headers['Cache-Control'] = 'no-cache';
debugPrint('📡 [SseClient] Sending message stream request to $url');
debugPrint('📡 [SseClient] Request headers: ${request.headers}');
final streamedResponse = await _httpClient!.send(request).timeout(
const Duration(seconds: 10),
onTimeout: () {
debugPrint('❌ [SseClient] Timeout waiting for response headers');
throw TimeoutException('Message stream connection timed out after 10 seconds');
},
);
debugPrint('📡 [SseClient] Received response with status: ${streamedResponse.statusCode}');
debugPrint('📡 [SseClient] Response headers: ${streamedResponse.headers}');
debugPrint('📡 [SseClient] Response content length: ${streamedResponse.contentLength}');
debugPrint('📡 [SseClient] Response is redirect: ${streamedResponse.isRedirect}');
if (streamedResponse.statusCode != 200) {
throw Exception('SSE messages subscription failed: ${streamedResponse.statusCode}');
}
debugPrint('📡 [SseClient] Message stream response received, status: ${streamedResponse.statusCode}');
debugPrint('📡 [SseClient] Setting up stream listener...');
_messageSubscription = streamedResponse.stream
.transform(utf8.decoder)
.transform(const LineSplitter())
.listen(
(line) {
debugPrint('📨 [SseClient] Received line: "$line"');
_handleSseLine(line, 'message');
},
onError: (error, stackTrace) {
debugPrint('❌ [SseClient] Message stream error: $error');
debugPrint(' Stack trace: $stackTrace');
_handleDisconnect();
},
onDone: () {
debugPrint('⚠️ [SseClient] Message stream closed (onDone called)');
_handleDisconnect();
},
cancelOnError: false,
);
debugPrint('✅ [SseClient] Message stream listener set up successfully');
} catch (e) {
debugPrint('❌ [SseClient] Error subscribing to message stream: $e');
rethrow;
}
}
/// Subscribe to SSE contact stream
Future<void> _subscribeToContacts() async {
try {
if (_httpClient == null) {
throw Exception('HTTP client not initialized');
}
debugPrint('📡 [SseClient] Creating contact stream request...');
final url = Uri.parse('$_serverUrl/sse/contacts');
final request = http.Request('GET', url);
request.headers.addAll(_getHeaders());
request.headers['Accept'] = 'text/event-stream';
request.headers['Cache-Control'] = 'no-cache';
debugPrint('📡 [SseClient] Sending contact stream request to $url');
final streamedResponse = await _httpClient!.send(request).timeout(
const Duration(seconds: 10),
onTimeout: () {
throw TimeoutException('Contact stream connection timed out after 10 seconds');
},
);
if (streamedResponse.statusCode != 200) {
throw Exception('SSE contacts subscription failed: ${streamedResponse.statusCode}');
}
debugPrint('📡 [SseClient] Contact stream response received, status: ${streamedResponse.statusCode}');
debugPrint('📡 [SseClient] Setting up contact stream listener...');
_contactSubscription = streamedResponse.stream
.transform(utf8.decoder)
.transform(const LineSplitter())
.listen(
(line) {
debugPrint('📨 [SseClient] Received contact line: "$line"');
_handleSseLine(line, 'contact');
},
onError: (error, stackTrace) {
debugPrint('❌ [SseClient] Contact stream error: $error');
debugPrint(' Stack trace: $stackTrace');
_handleDisconnect();
},
onDone: () {
debugPrint('⚠️ [SseClient] Contact stream closed (onDone called)');
_handleDisconnect();
},
cancelOnError: false,
);
debugPrint('✅ [SseClient] Contact stream listener set up successfully');
} catch (e) {
debugPrint('❌ [SseClient] Error subscribing to contact stream: $e');
rethrow;
}
}
/// Handle SSE line
String _eventType = '';
void _handleSseLine(String line, String streamType) {
if (line.isEmpty) {
// Event complete, reset
_eventType = '';
return;
}
if (line.startsWith('event:')) {
_eventType = line.substring(6).trim();
} else if (line.startsWith('data:')) {
final jsonData = line.substring(5).trim();
try {
final data = jsonDecode(jsonData) as Map<String, dynamic>;
if (streamType == 'message' && _eventType == 'message') {
final message = _messageFromJson(data);
onMessageReceived?.call(message);
} else if (streamType == 'contact' && _eventType == 'contact') {
final contact = _contactFromJson(data);
onContactReceived?.call(contact);
}
} catch (e) {
debugPrint('⚠️ [SseClient] Failed to parse SSE data: $e');
}
}
}
/// Handle disconnect
void _handleDisconnect() {
if (!_isConnected) return;
_isConnected = false;
onConnectionStateChanged?.call(false);
_scheduleReconnect();
}
/// Schedule reconnection attempt
void _scheduleReconnect() {
if (_reconnectAttempts >= _maxReconnectAttempts) {
debugPrint('❌ [SseClient] Max reconnection attempts reached');
onError?.call('Max reconnection attempts reached');
return;
}
_reconnectAttempts++;
final delay = _reconnectDelay * _reconnectAttempts;
debugPrint('🔄 [SseClient] Scheduling reconnect attempt $_reconnectAttempts in ${delay.inSeconds}s');
_reconnectTimer?.cancel();
_reconnectTimer = Timer(delay, () {
if (_serverUrl != null) {
connect(serverUrl: _serverUrl!, authToken: _authToken);
}
});
}
/// Start heartbeat to detect connection loss
void _startHeartbeat() {
_heartbeatTimer?.cancel();
_heartbeatTimer = Timer.periodic(const Duration(seconds: 30), (timer) async {
try {
await _checkServerStatus();
} catch (e) {
debugPrint('⚠️ [SseClient] Heartbeat failed: $e');
_handleDisconnect();
}
});
}
/// Send message to server
Future<bool> sendMessage({
required String recipientPublicKey,
required String text,
}) async {
if (!_isConnected || _serverUrl == null) {
throw Exception('Not connected to server');
}
try {
final url = Uri.parse('$_serverUrl/api/messages');
final response = await http.post(
url,
headers: {
..._getHeaders(),
'Content-Type': 'application/json',
},
body: jsonEncode({
'recipientPublicKey': recipientPublicKey,
'text': text,
}),
).timeout(const Duration(seconds: 10));
if (response.statusCode != 200) {
throw Exception('Send message failed: ${response.statusCode}');
}
final data = jsonDecode(response.body) as Map<String, dynamic>;
return data['success'] as bool? ?? false;
} catch (e) {
debugPrint('❌ [SseClient] Error sending message: $e');
rethrow;
}
}
/// Send channel message to server
Future<void> sendChannelMessage({
required int channelIdx,
required String text,
}) async {
if (!_isConnected || _serverUrl == null) {
throw Exception('Not connected to server');
}
try {
final url = Uri.parse('$_serverUrl/api/messages/channel');
final response = await http.post(
url,
headers: {
..._getHeaders(),
'Content-Type': 'application/json',
},
body: jsonEncode({
'channelIdx': channelIdx,
'text': text,
}),
).timeout(const Duration(seconds: 10));
if (response.statusCode != 200) {
throw Exception('Send channel message failed: ${response.statusCode}');
}
} catch (e) {
debugPrint('❌ [SseClient] Error sending channel message: $e');
rethrow;
}
}
/// Request contact sync
Future<void> syncContacts() async {
if (!_isConnected || _serverUrl == null) {
throw Exception('Not connected to server');
}
try {
final url = Uri.parse('$_serverUrl/api/contacts/sync');
final response = await http.post(
url,
headers: _getHeaders(),
).timeout(const Duration(seconds: 10));
if (response.statusCode != 200) {
throw Exception('Contact sync failed: ${response.statusCode}');
}
debugPrint('✅ [SseClient] Contact sync requested');
} catch (e) {
debugPrint('❌ [SseClient] Error syncing contacts: $e');
rethrow;
}
}
/// Get headers for HTTP requests
Map<String, String> _getHeaders() {
final headers = <String, String>{};
if (_authToken != null) {
headers['Authorization'] = 'Bearer $_authToken';
}
return headers;
}
/// Convert JSON to Message
Message _messageFromJson(Map<String, dynamic> json) {
return Message(
id: json['id'] as String,
messageType: MessageType.values.firstWhere(
(e) => e.name == json['messageType'],
orElse: () => MessageType.contact,
),
senderPublicKeyPrefix: json['senderPublicKeyPrefix'] != null
? Uint8List.fromList((json['senderPublicKeyPrefix'] as List).cast<int>())
: null,
channelIdx: json['channelIdx'] as int?,
pathLen: json['pathLen'] as int,
textType: MessageTextType.fromValue(json['textType'] as int),
senderTimestamp: json['senderTimestamp'] as int,
text: json['text'] as String,
isSarMarker: json['isSarMarker'] as bool? ?? false,
sarGpsCoordinates: json['sarGpsCoordinates'] != null
? LatLng(
(json['sarGpsCoordinates']['latitude'] as num).toDouble(),
(json['sarGpsCoordinates']['longitude'] as num).toDouble(),
)
: null,
sarNotes: json['sarNotes'] as String?,
sarCustomEmoji: json['sarCustomEmoji'] as String?,
sarColorIndex: json['sarColorIndex'] as int?,
receivedAt: DateTime.parse(json['receivedAt'] as String),
senderName: json['senderName'] as String?,
deliveryStatus: MessageDeliveryStatus.values.firstWhere(
(e) => e.name == json['deliveryStatus'],
orElse: () => MessageDeliveryStatus.received,
),
expectedAckTag: json['expectedAckTag'] as int?,
suggestedTimeoutMs: json['suggestedTimeoutMs'] as int?,
roundTripTimeMs: json['roundTripTimeMs'] as int?,
deliveredAt: json['deliveredAt'] != null
? DateTime.parse(json['deliveredAt'] as String)
: null,
recipientPublicKey: json['recipientPublicKey'] != null
? Uint8List.fromList((json['recipientPublicKey'] as List).cast<int>())
: null,
retryAttempt: json['retryAttempt'] as int? ?? 0,
lastRetryAt: json['lastRetryAt'] != null
? DateTime.parse(json['lastRetryAt'] as String)
: null,
usedFloodFallback: json['usedFloodFallback'] as bool? ?? false,
isRead: json['isRead'] as bool? ?? false,
echoCount: json['echoCount'] as int? ?? 0,
firstEchoAt: json['firstEchoAt'] != null
? DateTime.parse(json['firstEchoAt'] as String)
: null,
isDrawing: json['isDrawing'] as bool? ?? false,
drawingId: json['drawingId'] as String?,
);
}
/// Convert JSON to Contact
Contact _contactFromJson(Map<String, dynamic> json) {
return Contact(
publicKey: Uint8List.fromList((json['publicKey'] as List).cast<int>()),
type: ContactType.fromValue(json['type'] as int),
flags: json['flags'] as int,
outPathLen: json['outPathLen'] as int,
outPath: Uint8List.fromList((json['outPath'] as List).cast<int>()),
advName: json['advName'] as String,
lastAdvert: json['lastAdvert'] as int,
advLat: json['advLat'] as int,
advLon: json['advLon'] as int,
lastMod: json['lastMod'] as int,
);
}
/// Dispose resources
void dispose() {
disconnect();
}
}