Log contact data without revealing

lib/models/message_contact_location.dart

@@ -0,0 +1,63 @@
+import 'package:latlong2/latlong.dart';
+
+class MessageContactLocation {
+  final LatLng location;
+  final String source;
+  final DateTime capturedAt;
+  final DateTime? sourceTimestamp;
+
+  const MessageContactLocation({
+    required this.location,
+    required this.source,
+    required this.capturedAt,
+    this.sourceTimestamp,
+  });
+
+  String get technicalSourceLabel {
+    switch (source) {
+      case 'telemetry':
+        return 'telemetry';
+      case 'advert':
+        return 'advert';
+      default:
+        return source;
+    }
+  }
+
+  String get formattedCoordinates =>
+      '${location.latitude.toStringAsFixed(6)}, ${location.longitude.toStringAsFixed(6)}';
+
+  Map<String, dynamic> toJson() {
+    return {
+      'latitude': location.latitude,
+      'longitude': location.longitude,
+      'source': source,
+      'capturedAtMillis': capturedAt.millisecondsSinceEpoch,
+      'sourceTimestampMillis': sourceTimestamp?.millisecondsSinceEpoch,
+    };
+  }
+
+  static MessageContactLocation? fromJson(Map<String, dynamic> json) {
+    final latitude = json['latitude'];
+    final longitude = json['longitude'];
+    final source = json['source'];
+    final capturedAtMillis = json['capturedAtMillis'];
+    if (latitude is! num ||
+        longitude is! num ||
+        source is! String ||
+        capturedAtMillis is! int) {
+      return null;
+    }
+
+    return MessageContactLocation(
+      location: LatLng(latitude.toDouble(), longitude.toDouble()),
+      source: source,
+      capturedAt: DateTime.fromMillisecondsSinceEpoch(capturedAtMillis),
+      sourceTimestamp: json['sourceTimestampMillis'] is int
+          ? DateTime.fromMillisecondsSinceEpoch(
+              json['sourceTimestampMillis'] as int,
+            )
+          : null,
+    );
+  }
+}