Merge branch 'dev' into update-pacox-multibyte

lib/helpers/path_hop_resolver.dart

@@ -0,0 +1,75 @@
+import 'package:latlong2/latlong.dart';
+
+import '../connector/meshcore_protocol.dart';
+import 'path_helper.dart';
+import '../models/contact.dart';
+
+class PathHopResolver {
+  const PathHopResolver._();
+
+  static List<Contact?> resolve({
+    required List<int> pathBytes,
+    required List<Contact> contacts,
+    LatLng? endpoint,
+    bool resolveFromEnd = false,
+    int pathHashByteWidth = 1,
+  }) {
+    final width = pathHashByteWidth.clamp(1, 4).toInt();
+    final candidatesByPrefix = <String, List<Contact>>{};
+    for (final contact in contacts) {
+      if (contact.publicKey.length < width) continue;
+      if (contact.type != advTypeRepeater && contact.type != advTypeRoom) {
+        continue;
+      }
+      final prefix = PathHelper.formatHopHex(contact.publicKey.sublist(0, width));
+      candidatesByPrefix
+          .putIfAbsent(prefix, () => <Contact>[])
+          .add(contact);
+    }
+    for (final candidates in candidatesByPrefix.values) {
+      candidates.sort((a, b) => b.lastSeen.compareTo(a.lastSeen));
+    }
+
+    final hops = PathHelper.splitPathBytes(pathBytes, width);
+    final resolved = List<Contact?>.filled(hops.length, null);
+    final indexes = resolveFromEnd
+        ? List<int>.generate(hops.length, (i) => hops.length - 1 - i)
+        : List<int>.generate(hops.length, (i) => i);
+    final distance = Distance();
+    var previousPosition = endpoint;
+
+    for (final index in indexes) {
+      final candidates = candidatesByPrefix[PathHelper.formatHopHex(hops[index])];
+      if (candidates == null || candidates.isEmpty) continue;
+
+      var bestIndex = 0;
+      if (previousPosition != null && candidates.length > 1) {
+        double? nearestDistance;
+        for (var i = 0; i < candidates.length; i++) {
+          final position = _positionOf(candidates[i]);
+          if (position == null) continue;
+          final candidateDistance = distance(previousPosition, position);
+          if (nearestDistance == null || candidateDistance < nearestDistance) {
+            nearestDistance = candidateDistance;
+            bestIndex = i;
+          }
+        }
+      }
+
+      final contact = candidates.removeAt(bestIndex);
+      resolved[index] = contact;
+      previousPosition = _positionOf(contact) ?? previousPosition;
+    }
+
+    return resolved;
+  }
+
+  static LatLng? _positionOf(Contact contact) {
+    if (!contact.hasLocation ||
+        contact.latitude == null ||
+        contact.longitude == null) {
+      return null;
+    }
+    return LatLng(contact.latitude!, contact.longitude!);
+  }
+}

lib/helpers/snack_bar_builder.dart

@@ -25,7 +25,19 @@ void showDismissibleSnackBar(
   DismissDirection? dismissDirection,
   Clip? clipBehavior,
 }) {
-  final messenger = ScaffoldMessenger.of(context);
+  // Callers often reach here after an async gap; the context may already be
+  // unmounted, or deactivated (popped but not yet disposed) — ancestor
+  // lookups on a deactivated element throw. Showing nothing is the right
+  // outcome in both cases.
+  if (!context.mounted) return;
+  var isActive = true;
+  assert(() {
+    isActive = (context as Element).debugIsActive;
+    return true;
+  }());
+  if (!isActive) return;
+  final messenger = ScaffoldMessenger.maybeOf(context);
+  if (messenger == null) return;
   messenger.showSnackBar(
     SnackBar(
       key: key,