Fix tracing path and display issues

test/services/path_history_service_test.dart

@@ -161,15 +161,23 @@ void main() {
     expect(selection.mode, PathSelectionMode.flood);
   });
 
-  test('received public byte path is added to history', () async {
-    final service = PathHistoryService();
-    await service.initialize();
-    await service.recordReceivedBytePath('abc123', [0x01, 0x02, 0x03], 3);
+  test(
+    'received public byte path is reversed before adding to history',
+    () async {
+      final service = PathHistoryService();
+      await service.initialize();
+      await service.recordReceivedBytePath('abc123', [
+        0x01,
+        0x02,
+        0x03,
+        0x04,
+      ], 2);
 
-    final history = service.historyFor('abc123');
-    expect(history.directPaths, hasLength(1));
-    expect(history.directPaths.single.pathBytes, [0x01, 0x02, 0x03]);
-    expect(history.directPaths.single.hashSize, 3);
-    expect(history.directPaths.single.hopCount, 1);
-  });
+      final history = service.historyFor('abc123');
+      expect(history.directPaths, hasLength(1));
+      expect(history.directPaths.single.pathBytes, [0x03, 0x04, 0x01, 0x02]);
+      expect(history.directPaths.single.hashSize, 2);
+      expect(history.directPaths.single.hopCount, 2);
+    },
+  );
 }

test/utils/log_rx_route_decoder_test.dart

@@ -116,6 +116,21 @@ void main() {
       expect(resolved.matchCount, 2);
     });
   });
+
+  group('LogRxRouteDecoder.reverseHopBytes', () {
+    test('reverses path by hop size', () {
+      final reversed = LogRxRouteDecoder.reverseHopBytes([
+        0xc2,
+        0xba,
+        0x5f,
+        0xde,
+        0xaa,
+        0xbb,
+      ], hashSize: 2);
+
+      expect(reversed, [0xaa, 0xbb, 0x5f, 0xde, 0xc2, 0xba]);
+    });
+  });
 }
 
 Contact _contact({required String name, required List<int> keyPrefix}) {

test/utils/trace_node_resolver_test.dart

@@ -0,0 +1,80 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:latlong2/latlong.dart';
+import 'package:meshcore_sar_app/services/mesh_map_nodes_service.dart';
+import 'package:meshcore_sar_app/utils/trace_node_resolver.dart';
+
+void main() {
+  test(
+    'prefers closest local repeater over online fallback for shared prefix',
+    () {
+      final localNear = _node(
+        name: 'Near Local',
+        publicKey: 'aa1100',
+        latitude: 46.05,
+        longitude: 14.50,
+      );
+      final localFar = _node(
+        name: 'Far Local',
+        publicKey: 'aa2200',
+        latitude: 46.40,
+        longitude: 14.90,
+      );
+      final online = _node(
+        name: 'Online',
+        publicKey: 'aa3300',
+        latitude: 46.06,
+        longitude: 14.51,
+      );
+
+      final resolved = TraceNodeResolver.resolveBest(
+        nodes: [localNear, localFar, online],
+        localPublicKeys: {localNear.publicKey, localFar.publicKey},
+        prefixHex: 'aa',
+        referenceA: const LatLng(46.0, 14.5),
+        referenceB: const LatLng(46.1, 14.5),
+      );
+
+      expect(resolved.node?.name, 'Near Local');
+      expect(resolved.usedOnlineFallback, isFalse);
+      expect(resolved.matchCount, 2);
+      expect(resolved.matchSummary, '2 local matches');
+    },
+  );
+
+  test('falls back to online node only when local match is missing', () {
+    final online = _node(
+      name: 'Online Only',
+      publicKey: 'bb1100',
+      latitude: 46.06,
+      longitude: 14.51,
+    );
+
+    final resolved = TraceNodeResolver.resolveBest(
+      nodes: [online],
+      localPublicKeys: const {},
+      prefixHex: 'bb',
+      referenceA: const LatLng(46.0, 14.5),
+      referenceB: const LatLng(46.1, 14.5),
+    );
+
+    expect(resolved.node?.name, 'Online Only');
+    expect(resolved.usedOnlineFallback, isTrue);
+    expect(resolved.matchCount, 1);
+  });
+}
+
+MeshMapNode _node({
+  required String name,
+  required String publicKey,
+  required double latitude,
+  required double longitude,
+}) {
+  return MeshMapNode(
+    type: 1,
+    name: name,
+    publicKey: publicKey,
+    latitude: latitude,
+    longitude: longitude,
+    updatedAtMs: 1,
+  );
+}

test/widgets/contact_tile_test.dart

@@ -0,0 +1,85 @@
+import 'dart:typed_data';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:meshcore_sar_app/l10n/app_localizations.dart';
+import 'package:meshcore_sar_app/models/contact.dart';
+import 'package:meshcore_sar_app/providers/connection_provider.dart';
+import 'package:meshcore_sar_app/providers/contacts_provider.dart';
+import 'package:meshcore_sar_app/providers/map_provider.dart';
+import 'package:meshcore_sar_app/providers/messages_provider.dart';
+import 'package:meshcore_sar_app/providers/sensors_provider.dart';
+import 'package:meshcore_sar_app/widgets/contacts/contact_tile.dart';
+import 'package:provider/provider.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+void main() {
+  setUp(() {
+    SharedPreferences.setMockInitialValues({});
+  });
+
+  Contact buildContact({
+    required String name,
+    required ContactType type,
+    int secondByte = 1,
+  }) {
+    final publicKey = Uint8List(32);
+    publicKey[1] = secondByte;
+
+    return Contact(
+      publicKey: publicKey,
+      type: type,
+      flags: 0,
+      outPathLen: 0,
+      outPath: Uint8List(64),
+      advName: name,
+      lastAdvert: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+      advLat: 46562000,
+      advLon: 14950000,
+      lastMod: DateTime.now().millisecondsSinceEpoch ~/ 1000,
+    );
+  }
+
+  Future<void> pumpTile(WidgetTester tester, Contact contact) async {
+    await tester.pumpWidget(
+      MultiProvider(
+        providers: [
+          ChangeNotifierProvider(create: (_) => ConnectionProvider()),
+          ChangeNotifierProvider(create: (_) => ContactsProvider()),
+          ChangeNotifierProvider(create: (_) => MessagesProvider()),
+          ChangeNotifierProvider(create: (_) => SensorsProvider()),
+          ChangeNotifierProvider(create: (_) => MapProvider()),
+        ],
+        child: MaterialApp(
+          localizationsDelegates: AppLocalizations.localizationsDelegates,
+          supportedLocales: AppLocalizations.supportedLocales,
+          home: Scaffold(body: ContactTile(contact: contact)),
+        ),
+      ),
+    );
+  }
+
+  testWidgets('shows trace action for non-channel contacts', (tester) async {
+    await pumpTile(
+      tester,
+      buildContact(name: 'John Smith', type: ContactType.chat),
+    );
+
+    await tester.tap(find.text('John Smith'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Trace'), findsOneWidget);
+  });
+
+  testWidgets('does not show trace action for channels', (tester) async {
+    await pumpTile(
+      tester,
+      buildContact(name: 'Ops', type: ContactType.channel, secondByte: 3),
+    );
+
+    await tester.tap(find.text('Ops'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Trace'), findsNothing);
+  });
+}