Redesign contact import screen

Feat/sensor telemetry preview

lib/providers/connection_provider.dart

@@ -1257,6 +1257,10 @@ class ConnectionProvider with ChangeNotifier {
         channelName: channelName,
         secret: secretBytes,
       );
+
+      // Reconcile local state from the device after the write completes,
+      // matching the delete flow so channel/contact lists refresh immediately.
+      await _activeService.getChannel(slotIdx);
     } catch (e) {
       if (_isChannelRefreshTimeoutError(e)) {
         debugPrint(

lib/providers/contacts_provider.dart

@@ -875,10 +875,19 @@ class ContactsProvider with ChangeNotifier {
           telemetry.gpsLocation,
         )) {
           debugPrint(
-            '  ⚠️ Retaining last valid GPS. Incoming telemetry GPS is invalid/missing: $incomingGps',
+            '  ⚠️ Incoming telemetry GPS is invalid/missing; keeping last known contact location as fallback: $incomingGps',
           );
         }
-        telemetry = mergedTelemetry;
+        telemetry = ContactTelemetry(
+          gpsLocation: telemetry.gpsLocation,
+          batteryPercentage: mergedTelemetry.batteryPercentage,
+          batteryMilliVolts: mergedTelemetry.batteryMilliVolts,
+          temperature: mergedTelemetry.temperature,
+          timestamp: mergedTelemetry.timestamp,
+          humidity: mergedTelemetry.humidity,
+          pressure: mergedTelemetry.pressure,
+          extraSensorData: telemetry.extraSensorData,
+        );
       }
 
       // Update contact with new telemetry AND last seen time
@@ -993,10 +1002,10 @@ class ContactsProvider with ChangeNotifier {
     // 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>{
-      ...?existingTelemetry?.extraSensorData,
-      ...?incomingTelemetry.extraSensorData,
-    };
+    final mergedExtraSensorData = _mergeExtraSensorData(
+      existingTelemetry?.extraSensorData,
+      incomingTelemetry.extraSensorData,
+    );
 
     return ContactTelemetry(
       gpsLocation: incomingGps ?? previousGps,
@@ -1017,6 +1026,49 @@ class ContactsProvider with ChangeNotifier {
     );
   }
 
+  Map<String, dynamic> _mergeExtraSensorData(
+    Map<String, dynamic>? existingExtraSensorData,
+    Map<String, dynamic>? incomingExtraSensorData,
+  ) {
+    final merged = <String, dynamic>{...?existingExtraSensorData};
+    if (incomingExtraSensorData == null || incomingExtraSensorData.isEmpty) {
+      return merged;
+    }
+
+    final incomingMetricFamilies = incomingExtraSensorData.keys
+        .map(_telemetryMetricFamilyForKey)
+        .whereType<String>()
+        .toSet();
+    if (incomingMetricFamilies.isNotEmpty) {
+      merged.removeWhere((key, _) {
+        final family = _telemetryMetricFamilyForKey(key);
+        return family != null && incomingMetricFamilies.contains(family);
+      });
+    }
+
+    merged.addAll(incomingExtraSensorData);
+    return merged;
+  }
+
+  String? _telemetryMetricFamilyForKey(String key) {
+    const sourcePrefix = '__source_channel:';
+    if (key.startsWith(sourcePrefix)) {
+      return key.substring(sourcePrefix.length);
+    }
+
+    final separatorIndex = key.lastIndexOf('_');
+    if (separatorIndex <= 0 || separatorIndex == key.length - 1) {
+      return key;
+    }
+
+    final suffix = key.substring(separatorIndex + 1);
+    if (int.tryParse(suffix) == null) {
+      return key;
+    }
+
+    return key.substring(0, separatorIndex);
+  }
+
   int _coordinateToAdvertMicrodegrees(double coordinate) {
     return (coordinate * 1e6).round();
   }

lib/screens/add_contact_screen.dart

@@ -151,107 +151,234 @@ class _AddContactScreenState extends State<AddContactScreen> {
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
     final normalized = _normalizeAdvertText(_advertController.text);
+    final colorScheme = theme.colorScheme;
 
     return Scaffold(
-      appBar: AppBar(title: const Text('Add Contact')),
+      appBar: AppBar(title: const Text('Import Contact')),
       body: ListView(
         padding: const EdgeInsets.all(16),
         children: [
-          Text(
-            'Import an exported contact advert, like meshcore-open.',
-            style: theme.textTheme.titleMedium,
-          ),
-          const SizedBox(height: 8),
-          Text(
-            'Paste a `meshcore://...` link or raw hex advert from the clipboard.',
-            style: theme.textTheme.bodyMedium?.copyWith(
-              color: theme.colorScheme.onSurfaceVariant,
-            ),
-          ),
-          const SizedBox(height: 16),
-          TextField(
-            controller: _advertController,
-            minLines: 4,
-            maxLines: 8,
-            onChanged: (_) {
-              if (_validationError != null || _importSucceeded) {
-                setState(() {
-                  _importSucceeded = false;
-                  _validationError = null;
-                });
-              }
-            },
-            decoration: InputDecoration(
-              labelText: 'Contact advert',
-              hintText: 'meshcore://...',
-              alignLabelWithHint: true,
-              border: const OutlineInputBorder(),
-              errorText: _validationError,
-            ),
-          ),
-          const SizedBox(height: 12),
-          if (normalized != null)
-            Text(
-              'Advert size: ${normalized.length ~/ 2} bytes',
-              style: theme.textTheme.bodySmall?.copyWith(
-                color: theme.colorScheme.onSurfaceVariant,
+          Container(
+            padding: const EdgeInsets.all(18),
+            decoration: BoxDecoration(
+              color: colorScheme.surfaceContainerHighest.withValues(alpha: 0.5),
+              borderRadius: BorderRadius.circular(20),
+              border: Border.all(
+                color: colorScheme.outlineVariant.withValues(alpha: 0.6),
               ),
             ),
-          const SizedBox(height: 20),
-          Row(
-            children: [
-              Expanded(
-                child: OutlinedButton.icon(
-                  onPressed: _isImporting ? null : _pasteFromClipboard,
-                  icon: const Icon(Icons.content_paste_go_outlined),
-                  label: const Text('Paste'),
-                ),
-              ),
-              const SizedBox(width: 12),
-              Expanded(
-                child: FilledButton.icon(
-                  onPressed: (_isImporting || _importSucceeded)
-                      ? null
-                      : _importContact,
-                  icon: _isImporting
-                      ? const SizedBox(
-                          width: 16,
-                          height: 16,
-                          child: CircularProgressIndicator(strokeWidth: 2),
-                        )
-                      : _importSucceeded
-                      ? const Icon(Icons.check_circle_outline)
-                      : const Icon(Icons.person_add_alt_1_outlined),
-                  label: Text(
-                    _isImporting
-                        ? 'Importing...'
-                        : _importSucceeded
-                        ? 'Added'
-                        : 'Add Contact',
-                  ),
-                ),
-              ),
-            ],
-          ),
-          if (_importSucceeded) ...[
-            const SizedBox(height: 12),
-            Row(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
               children: [
-                Icon(
-                  Icons.check_circle,
-                  size: 18,
-                  color: theme.colorScheme.primary,
+                Row(
+                  children: [
+                    Container(
+                      padding: const EdgeInsets.all(10),
+                      decoration: BoxDecoration(
+                        color: colorScheme.primary.withValues(alpha: 0.12),
+                        borderRadius: BorderRadius.circular(14),
+                      ),
+                      child: Icon(
+                        Icons.person_add_alt_1_outlined,
+                        color: colorScheme.primary,
+                      ),
+                    ),
+                    const SizedBox(width: 12),
+                    Expanded(
+                      child: Text(
+                        'Import a shared contact advert',
+                        style: theme.textTheme.titleMedium?.copyWith(
+                          fontWeight: FontWeight.w700,
+                        ),
+                      ),
+                    ),
+                  ],
                 ),
-                const SizedBox(width: 8),
+                const SizedBox(height: 14),
                 Text(
-                  'Contact added. Paste or edit another advert to import again.',
-                  style: theme.textTheme.bodySmall?.copyWith(
-                    color: theme.colorScheme.onSurfaceVariant,
+                  'Paste a `meshcore://...` link or raw hexadecimal advert. The app will validate it and import the contact into the connected device.',
+                  style: theme.textTheme.bodyMedium?.copyWith(
+                    color: colorScheme.onSurfaceVariant,
                   ),
                 ),
+                const SizedBox(height: 14),
+                Wrap(
+                  spacing: 8,
+                  runSpacing: 8,
+                  children: const [
+                    _ImportHintChip(
+                      icon: Icons.link_outlined,
+                      label: 'Accepts share links',
+                    ),
+                    _ImportHintChip(
+                      icon: Icons.code_outlined,
+                      label: 'Supports raw hex',
+                    ),
+                    _ImportHintChip(
+                      icon: Icons.content_paste_go_outlined,
+                      label: 'Clipboard-friendly',
+                    ),
+                  ],
+                ),
               ],
             ),
-          ],
+          ),
+          const SizedBox(height: 16),
+          Container(
+            padding: const EdgeInsets.all(16),
+            decoration: BoxDecoration(
+              color: colorScheme.surface,
+              borderRadius: BorderRadius.circular(20),
+              border: Border.all(
+                color: colorScheme.outlineVariant.withValues(alpha: 0.7),
+              ),
+            ),
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  'Advert payload',
+                  style: theme.textTheme.titleSmall?.copyWith(
+                    fontWeight: FontWeight.w700,
+                  ),
+                ),
+                const SizedBox(height: 6),
+                Text(
+                  'You can paste the full share link or only the hex payload.',
+                  style: theme.textTheme.bodySmall?.copyWith(
+                    color: colorScheme.onSurfaceVariant,
+                  ),
+                ),
+                const SizedBox(height: 12),
+                TextField(
+                  controller: _advertController,
+                  minLines: 5,
+                  maxLines: 9,
+                  onChanged: (_) {
+                    if (_validationError != null || _importSucceeded) {
+                      setState(() {
+                        _importSucceeded = false;
+                        _validationError = null;
+                      });
+                    }
+                  },
+                  decoration: InputDecoration(
+                    labelText: 'Contact advert',
+                    hintText: 'Paste a share link or hex advert',
+                    alignLabelWithHint: true,
+                    border: const OutlineInputBorder(),
+                    errorText: _validationError,
+                  ),
+                ),
+                const SizedBox(height: 12),
+                Row(
+                  children: [
+                    Expanded(
+                      child: Text(
+                        normalized == null
+                            ? 'No valid advert detected yet'
+                            : 'Advert size: ${normalized.length ~/ 2} bytes',
+                        style: theme.textTheme.bodySmall?.copyWith(
+                          color: colorScheme.onSurfaceVariant,
+                        ),
+                      ),
+                    ),
+                    TextButton.icon(
+                      onPressed: _isImporting ? null : _pasteFromClipboard,
+                      icon: const Icon(Icons.content_paste_go_outlined),
+                      label: const Text('Paste'),
+                    ),
+                  ],
+                ),
+              ],
+            ),
+          ),
+          const SizedBox(height: 20),
+          FilledButton.icon(
+            onPressed: (_isImporting || _importSucceeded)
+                ? null
+                : _importContact,
+            style: FilledButton.styleFrom(
+              padding: const EdgeInsets.symmetric(vertical: 14),
+            ),
+            icon: _isImporting
+                ? const SizedBox(
+                    width: 16,
+                    height: 16,
+                    child: CircularProgressIndicator(strokeWidth: 2),
+                  )
+                : _importSucceeded
+                ? const Icon(Icons.check_circle_outline)
+                : const Icon(Icons.person_add_alt_1_outlined),
+            label: Text(
+              _isImporting
+                  ? 'Importing...'
+                  : _importSucceeded
+                  ? 'Imported'
+                  : 'Import Contact',
+            ),
+          ),
+          const SizedBox(height: 12),
+          if (_importSucceeded)
+            Container(
+              padding: const EdgeInsets.all(14),
+              decoration: BoxDecoration(
+                color: colorScheme.primary.withValues(alpha: 0.08),
+                borderRadius: BorderRadius.circular(16),
+                border: Border.all(
+                  color: colorScheme.primary.withValues(alpha: 0.18),
+                ),
+              ),
+              child: Row(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Icon(
+                    Icons.check_circle,
+                    size: 18,
+                    color: colorScheme.primary,
+                  ),
+                  const SizedBox(width: 10),
+                  Expanded(
+                    child: Text(
+                      'Contact imported. Paste another advert or edit the current one to import again.',
+                      style: theme.textTheme.bodySmall?.copyWith(
+                        color: colorScheme.onSurfaceVariant,
+                      ),
+                    ),
+                  ),
+                ],
+              ),
+            ),
+        ],
+      ),
+    );
+  }
+}
+
+class _ImportHintChip extends StatelessWidget {
+  final IconData icon;
+  final String label;
+
+  const _ImportHintChip({required this.icon, required this.label});
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 8),
+      decoration: BoxDecoration(
+        color: theme.colorScheme.surface,
+        borderRadius: BorderRadius.circular(999),
+        border: Border.all(
+          color: theme.colorScheme.outlineVariant.withValues(alpha: 0.7),
+        ),
+      ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          Icon(icon, size: 16, color: theme.colorScheme.onSurfaceVariant),
+          const SizedBox(width: 6),
+          Text(label, style: theme.textTheme.labelMedium),
         ],
       ),
     );

lib/screens/contacts_tab.dart

@@ -675,7 +675,7 @@ class _ContactsTabState extends State<ContactsTab> {
                       child: OutlinedButton.icon(
                         onPressed: () => _openAddContactScreen(context),
                         icon: const Icon(Icons.person_add_alt_1_outlined),
-                        label: const Text('Add Contact'),
+                        label: const Text('Import Contact'),
                       ),
                     ),
                 ],
@@ -887,7 +887,7 @@ class _ContactsTabState extends State<ContactsTab> {
                           child: OutlinedButton.icon(
                             onPressed: () => _openAddContactScreen(context),
                             icon: const Icon(Icons.person_add_alt_1_outlined),
-                            label: const Text('Add Contact'),
+                            label: const Text('Import Contact'),
                             style: OutlinedButton.styleFrom(
                               padding: const EdgeInsets.symmetric(
                                 horizontal: 24,

test/providers/contacts_provider_test.dart

@@ -137,7 +137,7 @@ void main() {
     });
 
     test(
-      'retains last valid gps for any contact when telemetry gps is invalid or missing',
+      'clears telemetry gps on refresh when gps is invalid or missing but keeps fallback display location',
       () {
         final contactTypes = <ContactType>[
           ContactType.chat,
@@ -165,23 +165,24 @@ void main() {
           );
           scopedProvider.updateTelemetry(scopedKey.sublist(0, 6), validGps);
 
-          // No GPS frame should keep previous valid GPS.
+          // No GPS frame should clear telemetry GPS but keep the last known
+          // contact location as display fallback.
           final batteryOnly = CayenneLppParser.createBatteryData(3.8);
           scopedProvider.updateTelemetry(scopedKey.sublist(0, 6), batteryOnly);
 
           var updated = scopedProvider.findContactByKey(scopedKey)!;
           expect(updated.telemetry, isNotNull);
-          expect(updated.telemetry!.gpsLocation, isNotNull);
+          expect(updated.telemetry!.gpsLocation, isNull);
           expect(
-            updated.telemetry!.gpsLocation!.latitude,
+            updated.displayLocation!.latitude,
             closeTo(45.1234, 0.0001),
           );
           expect(
-            updated.telemetry!.gpsLocation!.longitude,
+            updated.displayLocation!.longitude,
             closeTo(13.8765, 0.0001),
           );
 
-          // Invalid 0,0 GPS frame should also keep previous valid GPS.
+          // Invalid 0,0 GPS frame should behave the same way.
           final invalidGps = CayenneLppParser.createGpsData(
             latitude: 0.0,
             longitude: 0.0,
@@ -190,13 +191,13 @@ void main() {
 
           updated = scopedProvider.findContactByKey(scopedKey)!;
           expect(updated.telemetry, isNotNull);
-          expect(updated.telemetry!.gpsLocation, isNotNull);
+          expect(updated.telemetry!.gpsLocation, isNull);
           expect(
-            updated.telemetry!.gpsLocation!.latitude,
+            updated.displayLocation!.latitude,
             closeTo(45.1234, 0.0001),
           );
           expect(
-            updated.telemetry!.gpsLocation!.longitude,
+            updated.displayLocation!.longitude,
             closeTo(13.8765, 0.0001),
           );
         }
@@ -336,7 +337,7 @@ void main() {
       expect(updated.telemetry!.extraSensorData, containsPair('co2', 415.0));
     });
 
-    test('retains prior telemetry fields across sparse telemetry updates', () {
+    test('retains scalar telemetry but wipes stale extra sensor fields on refresh', () {
       final fullTelemetry = ContactTelemetry(
         gpsLocation: const LatLng(46.0569, 14.5058),
         batteryPercentage: 54.0,
@@ -360,13 +361,70 @@ void main() {
 
       final updated = provider.findContactByKey(publicKey)!;
       expect(updated.telemetry, isNotNull);
-      expect(updated.telemetry!.gpsLocation, const LatLng(46.0569, 14.5058));
+      expect(updated.telemetry!.gpsLocation, isNull);
+      expect(updated.displayLocation, 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));
+      expect(
+        updated.telemetry!.extraSensorData,
+        containsPair('__source_channel:battery', 0),
+      );
+      expect(
+        updated.telemetry!.extraSensorData,
+        containsPair('__source_channel:voltage', 0),
+      );
+      expect(updated.telemetry!.extraSensorData, isNot(contains('pm25')));
+    });
+
+    test('replaces old source-channel mappings when a metric moves channels', () {
+      final initialTelemetry = ContactTelemetry(
+        gpsLocation: null,
+        batteryPercentage: null,
+        batteryMilliVolts: null,
+        temperature: 21.5,
+        timestamp: DateTime.now().subtract(const Duration(minutes: 2)),
+        humidity: null,
+        pressure: null,
+        extraSensorData: const {
+          '__source_channel:temperature': 2,
+          'temperature_2': 21.5,
+          'humidity_4': 66.0,
+        },
+      );
+
+      provider.addOrUpdateContact(
+        createContact(
+          key: publicKey,
+          type: ContactType.chat,
+        ).copyWith(telemetry: initialTelemetry),
+      );
+
+      final movedChannelTelemetry = CayenneLppParser.createTemperatureData(
+        23.5,
+        channel: 3,
+      );
+
+      provider.updateTelemetry(publicKey.sublist(0, 6), movedChannelTelemetry);
+
+      final updated = provider.findContactByKey(publicKey)!;
+      expect(updated.telemetry, isNotNull);
+      expect(updated.telemetry!.temperature, closeTo(23.5, 0.1));
+      expect(
+        updated.telemetry!.extraSensorData,
+        containsPair('__source_channel:temperature', 3),
+      );
+      expect(
+        updated.telemetry!.extraSensorData,
+        containsPair('temperature_3', closeTo(23.5, 0.1)),
+      );
+      expect(
+        updated.telemetry!.extraSensorData,
+        isNot(contains('temperature_2')),
+      );
+      expect(updated.telemetry!.extraSensorData, isNot(contains('humidity_4')));
     });
 
     test('builds message snapshot from latest valid telemetry', () {