Preserve contact telemetry data

lib/providers/contacts_provider.dart

@@ -283,62 +283,16 @@ class ContactsProvider with ChangeNotifier {
     }
 
     // Check if this is a new contact
-    final isNewContact = !_contacts.containsKey(contact.publicKeyHex);
+    final existingContact = _contacts[contact.publicKeyHex];
+    final isNewContact = existingContact == null;
     debugPrint(
       '   isNew: $isNewContact, total contacts before: ${_contacts.length}',
     );
 
-    Contact updatedContact;
+    final updatedContact = _mergeIncomingContact(
-    if (isNewContact) {
+      incomingContact: contact,
-      // New contact - add initial location to history if available
+      existingContact: existingContact,
-      updatedContact = contact.copyWith(isNew: true);
+    );
-      if (contact.advertLocation != null) {
-        final timestamp = DateTime.fromMillisecondsSinceEpoch(
-          contact.lastAdvert * 1000,
-        );
-        updatedContact = updatedContact.addAdvertLocation(
-          contact.advertLocation!,
-          timestamp,
-        );
-      }
-    } else {
-      // Existing contact - preserve history and isNew status
-      final existingContact = _contacts[contact.publicKeyHex]!;
-      final mergedTelemetry = _mergeTelemetryForContact(
-        existingTelemetry: existingContact.telemetry,
-        incomingTelemetry: contact.telemetry,
-      );
-      final incomingAdvertLocation = contact.advertLocation;
-      final existingAdvertLocation = existingContact.advertLocation;
-
-      // Start with existing contact
-      updatedContact = contact.copyWith(
-        isNew: existingContact.isNew,
-        advertHistory: existingContact.advertHistory,
-        telemetry: mergedTelemetry,
-        advLat: incomingAdvertLocation != null
-            ? contact.advLat
-            : existingAdvertLocation != null
-            ? existingContact.advLat
-            : contact.advLat,
-        advLon: incomingAdvertLocation != null
-            ? contact.advLon
-            : existingAdvertLocation != null
-            ? existingContact.advLon
-            : contact.advLon,
-      );
-
-      // Add new location to history if location has changed
-      if (contact.advertLocation != null) {
-        final timestamp = DateTime.fromMillisecondsSinceEpoch(
-          contact.lastAdvert * 1000,
-        );
-        updatedContact = updatedContact.addAdvertLocation(
-          contact.advertLocation!,
-          timestamp,
-        );
-      }
-    }
 
     _contacts[contact.publicKeyHex] = updatedContact;
     _pendingAdverts.remove(contact.publicKeyHex);
@@ -364,7 +318,11 @@ class ContactsProvider with ChangeNotifier {
         excluded++;
         continue;
       }
-      _contacts[contact.publicKeyHex] = contact;
+      final existingContact = _contacts[contact.publicKeyHex];
+      _contacts[contact.publicKeyHex] = _mergeIncomingContact(
+        incomingContact: contact,
+        existingContact: existingContact,
+      );
       _pendingAdverts.remove(contact.publicKeyHex);
     }
     if (excluded > 0) {
@@ -376,6 +334,60 @@ class ContactsProvider with ChangeNotifier {
     notifyListeners();
   }
 
+  Contact _mergeIncomingContact({
+    required Contact incomingContact,
+    Contact? existingContact,
+  }) {
+    if (existingContact == null) {
+      var newContact = incomingContact.copyWith(isNew: true);
+      if (incomingContact.advertLocation != null) {
+        final timestamp = DateTime.fromMillisecondsSinceEpoch(
+          incomingContact.lastAdvert * 1000,
+        );
+        newContact = newContact.addAdvertLocation(
+          incomingContact.advertLocation!,
+          timestamp,
+        );
+      }
+      return newContact;
+    }
+
+    final mergedTelemetry = _mergeTelemetryForContact(
+      existingTelemetry: existingContact.telemetry,
+      incomingTelemetry: incomingContact.telemetry,
+    );
+    final incomingAdvertLocation = incomingContact.advertLocation;
+    final existingAdvertLocation = existingContact.advertLocation;
+
+    var updatedContact = incomingContact.copyWith(
+      isNew: existingContact.isNew,
+      advertHistory: existingContact.advertHistory,
+      telemetry: mergedTelemetry,
+      advLat: incomingAdvertLocation != null
+          ? incomingContact.advLat
+          : existingAdvertLocation != null
+          ? existingContact.advLat
+          : incomingContact.advLat,
+      advLon: incomingAdvertLocation != null
+          ? incomingContact.advLon
+          : existingAdvertLocation != null
+          ? existingContact.advLon
+          : incomingContact.advLon,
+    );
+
+    if (incomingAdvertLocation != null) {
+      final timestamp = DateTime.fromMillisecondsSinceEpoch(
+        incomingContact.lastAdvert * 1000,
+      );
+      updatedContact = updatedContact.addAdvertLocation(
+        incomingAdvertLocation,
+        timestamp,
+      );
+    }
+
+    return updatedContact;
+  }
+
   /// Update contact telemetry
   void updateTelemetry(Uint8List publicKeyPrefix, Uint8List lppData) {
     debugPrint('📊 [ContactsProvider] updateTelemetry() called');
@@ -541,6 +553,8 @@ class ContactsProvider with ChangeNotifier {
       return existingTelemetry;
     }
 
+    // Telemetry packets and contact refreshes are often sparse. Preserve the
+    // last known reading for any field that is omitted in the incoming update.
     final incomingGps = _getValidGpsOrNull(incomingTelemetry.gpsLocation);
     final previousGps = _getValidGpsOrNull(existingTelemetry?.gpsLocation);
     final mergedExtraSensorData = <String, dynamic>{

lib/providers/sensors_provider.dart

@@ -220,35 +220,48 @@ class SensorsProvider with ChangeNotifier {
 
     try {
       for (final key in _watchedSensorKeys) {
-        Contact? contact;
+        await refreshSensor(
-        for (final entry in contactsProvider.contacts) {
+          publicKeyHex: key,
-          if (entry.publicKeyHex == key) {
+          contactsProvider: contactsProvider,
-            contact = entry;
+          connectionProvider: connectionProvider,
-            break;
-          }
-        }
-        if (contact == null) {
-          _refreshStates[key] = SensorRefreshState.unavailable;
-          notifyListeners();
-          continue;
-        }
-
-        _refreshStates[key] = SensorRefreshState.refreshing;
-        notifyListeners();
-
-        final result = await connectionProvider.smartPing(
-          contactPublicKey: contact.publicKey,
-          hasPath: contact.hasPath,
         );
-
-        _refreshStates[key] = result.success
-            ? SensorRefreshState.success
-            : SensorRefreshState.timeout;
-        notifyListeners();
       }
     } finally {
       _isRefreshingAll = false;
       notifyListeners();
     }
   }
+
+  Future<void> refreshSensor({
+    required String publicKeyHex,
+    required ContactsProvider contactsProvider,
+    required ConnectionProvider connectionProvider,
+  }) async {
+    Contact? contact;
+    for (final entry in contactsProvider.contacts) {
+      if (entry.publicKeyHex == publicKeyHex) {
+        contact = entry;
+        break;
+      }
+    }
+
+    if (contact == null) {
+      _refreshStates[publicKeyHex] = SensorRefreshState.unavailable;
+      notifyListeners();
+      return;
+    }
+
+    _refreshStates[publicKeyHex] = SensorRefreshState.refreshing;
+    notifyListeners();
+
+    final result = await connectionProvider.smartPing(
+      contactPublicKey: contact.publicKey,
+      hasPath: contact.hasPath,
+    );
+
+    _refreshStates[publicKeyHex] = result.success
+        ? SensorRefreshState.success
+        : SensorRefreshState.timeout;
+    notifyListeners();
+  }
 }

lib/screens/sensors_tab.dart

@@ -209,6 +209,11 @@ class SensorsTab extends StatelessWidget {
                       },
                       onCustomize: () =>
                           _showMetricSelector(context, key, contact),
+                      onRefresh: () => sensorsProvider.refreshSensor(
+                        publicKeyHex: key,
+                        contactsProvider: contactsProvider,
+                        connectionProvider: context.read<ConnectionProvider>(),
+                      ),
                     );
                   }),
               ],
@@ -302,6 +307,7 @@ class _SensorCard extends StatelessWidget {
   final Set<String> visibleFields;
   final Map<String, int> fieldSpans;
   final Future<void> Function() onRemove;
+  final Future<void> Function() onRefresh;
   final VoidCallback onCustomize;
 
   const _SensorCard({
@@ -310,6 +316,7 @@ class _SensorCard extends StatelessWidget {
     required this.visibleFields,
     required this.fieldSpans,
     required this.onRemove,
+    required this.onRefresh,
     required this.onCustomize,
   });
 
@@ -404,18 +411,24 @@ class _SensorCard extends StatelessWidget {
                 ),
                 PopupMenuButton<String>(
                   onSelected: (value) async {
-                    if (value == 'remove') {
+                    if (value == 'refresh') {
+                      await onRefresh();
+                    } else if (value == 'remove') {
                       await onRemove();
                     } else if (value == 'customize') {
                       onCustomize();
                     }
                   },
-                  itemBuilder: (context) => const [
+                  itemBuilder: (context) => [
                     PopupMenuItem<String>(
+                      value: 'refresh',
+                      child: Text(l10n.refresh),
+                    ),
+                    const PopupMenuItem<String>(
                       value: 'customize',
                       child: Text('Customize fields'),
                     ),
-                    PopupMenuItem<String>(
+                    const PopupMenuItem<String>(
                       value: 'remove',
                       child: Text('Remove'),
                     ),
@@ -429,7 +442,9 @@ class _SensorCard extends StatelessWidget {
                 'This node is no longer available in the contact list.',
               )
             else if (telemetry == null)
-              const Text('No telemetry received yet. Pull down to fetch it.')
+              const Text(
+                'No telemetry received yet. Use Refresh from the menu or pull down to fetch it.',
+              )
             else if (metrics.isEmpty)
               const Text(
                 'All fields are hidden. Use Visible fields to choose what to show.',

test/providers/contacts_provider_test.dart

@@ -1,6 +1,7 @@
 import 'dart:typed_data';
 
 import 'package:flutter_test/flutter_test.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:meshcore_sar_app/models/contact.dart';
 import 'package:meshcore_sar_app/providers/contacts_provider.dart';
 import 'package:meshcore_sar_app/services/cayenne_lpp_parser.dart';
@@ -242,6 +243,129 @@ void main() {
       },
     );
 
+    test('retains existing telemetry when contact refresh omits telemetry', () {
+      final initialTelemetry = ContactTelemetry(
+        gpsLocation: const LatLng(45.1234, 13.8765),
+        batteryPercentage: 76.5,
+        batteryMilliVolts: 3890,
+        temperature: 21.5,
+        timestamp: DateTime.now().subtract(const Duration(minutes: 5)),
+        humidity: 62.0,
+        pressure: 1008.4,
+        extraSensorData: const {'co2': 415.0},
+      );
+
+      provider.addOrUpdateContact(
+        createContact(
+          key: publicKey,
+          type: ContactType.chat,
+        ).copyWith(telemetry: initialTelemetry),
+      );
+
+      provider.addOrUpdateContact(
+        Contact(
+          publicKey: publicKey,
+          type: ContactType.chat,
+          flags: 0,
+          outPathLen: 0,
+          outPath: Uint8List(64),
+          advName: 'Test Contact Refreshed',
+          lastAdvert: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+          advLat: 0,
+          advLon: 0,
+          lastMod: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+        ),
+      );
+
+      final updated = provider.findContactByKey(publicKey)!;
+      expect(updated.telemetry, isNotNull);
+      expect(updated.telemetry!.gpsLocation, const LatLng(45.1234, 13.8765));
+      expect(updated.telemetry!.batteryPercentage, equals(76.5));
+      expect(updated.telemetry!.batteryMilliVolts, equals(3890));
+      expect(updated.telemetry!.temperature, equals(21.5));
+      expect(updated.telemetry!.humidity, equals(62.0));
+      expect(updated.telemetry!.pressure, equals(1008.4));
+      expect(updated.telemetry!.extraSensorData, containsPair('co2', 415.0));
+    });
+
+    test('retains existing telemetry during bulk contacts sync', () {
+      final initialTelemetry = ContactTelemetry(
+        gpsLocation: const LatLng(45.1234, 13.8765),
+        batteryPercentage: 76.5,
+        batteryMilliVolts: 3890,
+        temperature: 21.5,
+        timestamp: DateTime.now().subtract(const Duration(minutes: 5)),
+        humidity: 62.0,
+        pressure: 1008.4,
+        extraSensorData: const {'co2': 415.0},
+      );
+
+      provider.addOrUpdateContact(
+        createContact(
+          key: publicKey,
+          type: ContactType.chat,
+        ).copyWith(telemetry: initialTelemetry),
+      );
+
+      provider.addContacts([
+        Contact(
+          publicKey: publicKey,
+          type: ContactType.chat,
+          flags: 0,
+          outPathLen: 0,
+          outPath: Uint8List(64),
+          advName: 'Synced Contact',
+          lastAdvert: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+          advLat: 0,
+          advLon: 0,
+          lastMod: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+        ),
+      ]);
+
+      final updated = provider.findContactByKey(publicKey)!;
+      expect(updated.telemetry, isNotNull);
+      expect(updated.telemetry!.gpsLocation, const LatLng(45.1234, 13.8765));
+      expect(updated.telemetry!.batteryPercentage, equals(76.5));
+      expect(updated.telemetry!.batteryMilliVolts, equals(3890));
+      expect(updated.telemetry!.temperature, equals(21.5));
+      expect(updated.telemetry!.humidity, equals(62.0));
+      expect(updated.telemetry!.pressure, equals(1008.4));
+      expect(updated.telemetry!.extraSensorData, containsPair('co2', 415.0));
+    });
+
+    test('retains prior telemetry fields across sparse telemetry updates', () {
+      final fullTelemetry = ContactTelemetry(
+        gpsLocation: const LatLng(46.0569, 14.5058),
+        batteryPercentage: 54.0,
+        batteryMilliVolts: 3780,
+        temperature: 19.5,
+        timestamp: DateTime.now().subtract(const Duration(minutes: 2)),
+        humidity: 58.0,
+        pressure: 1011.2,
+        extraSensorData: const {'pm25': 8.0},
+      );
+
+      provider.addOrUpdateContact(
+        createContact(
+          key: publicKey,
+          type: ContactType.chat,
+        ).copyWith(telemetry: fullTelemetry),
+      );
+
+      final batteryOnly = CayenneLppParser.createBatteryData(3.95);
+      provider.updateTelemetry(publicKey.sublist(0, 6), batteryOnly);
+
+      final updated = provider.findContactByKey(publicKey)!;
+      expect(updated.telemetry, isNotNull);
+      expect(updated.telemetry!.gpsLocation, const LatLng(46.0569, 14.5058));
+      expect(updated.telemetry!.batteryMilliVolts, isNotNull);
+      expect(updated.telemetry!.batteryPercentage, isNotNull);
+      expect(updated.telemetry!.temperature, equals(19.5));
+      expect(updated.telemetry!.humidity, equals(58.0));
+      expect(updated.telemetry!.pressure, equals(1011.2));
+      expect(updated.telemetry!.extraSensorData, containsPair('pm25', 8.0));
+    });
+
     test('builds message snapshot from latest valid telemetry', () {
       final telemetryData = CayenneLppParser.createGpsData(
         latitude: 45.0001,