feat: Add geocoding functionality for trips and enhance activity search with coordinates

lib/models/trip.dart

@@ -19,6 +19,15 @@ class Trip {
   /// Trip destination or location.
   final String location;
 
+  /// Latitude coordinate of the trip location.
+  final double? latitude;
+
+  /// Longitude coordinate of the trip location.
+  final double? longitude;
+
+  /// Timestamp when the location was last geocoded.
+  final DateTime? lastGeocodingUpdate;
+
   /// Trip start date and time.
   final DateTime startDate;
 
@@ -54,6 +63,9 @@ class Trip {
     required this.title,
     required this.description,
     required this.location,
+    this.latitude,
+    this.longitude,
+    this.lastGeocodingUpdate,
     required this.startDate,
     required this.endDate,
     this.budget,
@@ -101,6 +113,11 @@ class Trip {
         title: map['title'] as String? ?? '',
         description: map['description'] as String? ?? '',
         location: map['location'] as String? ?? '',
+        latitude: (map['latitude'] as num?)?.toDouble(),
+        longitude: (map['longitude'] as num?)?.toDouble(),
+        lastGeocodingUpdate: map['lastGeocodingUpdate'] != null 
+            ? _parseDateTime(map['lastGeocodingUpdate'])
+            : null,
         startDate: _parseDateTime(map['startDate']),
         endDate: _parseDateTime(map['endDate']),
         budget: (map['budget'] as num?)?.toDouble(),
@@ -122,6 +139,11 @@ class Trip {
       'title': title,
       'description': description,
       'location': location,
+      'latitude': latitude,
+      'longitude': longitude,
+      'lastGeocodingUpdate': lastGeocodingUpdate != null 
+          ? Timestamp.fromDate(lastGeocodingUpdate!)
+          : null,
       'startDate': Timestamp.fromDate(startDate),
       'endDate': Timestamp.fromDate(endDate),
       'budget': budget,
@@ -145,6 +167,9 @@ class Trip {
     String? title,
     String? description,
     String? location,
+    double? latitude,
+    double? longitude,
+    DateTime? lastGeocodingUpdate,
     DateTime? startDate,
     DateTime? endDate,
     double? budget,
@@ -160,6 +185,9 @@ class Trip {
       title: title ?? this.title,
       description: description ?? this.description,
       location: location ?? this.location,
+      latitude: latitude ?? this.latitude,
+      longitude: longitude ?? this.longitude,
+      lastGeocodingUpdate: lastGeocodingUpdate ?? this.lastGeocodingUpdate,
       startDate: startDate ?? this.startDate,
       endDate: endDate ?? this.endDate,
       budget: budget ?? this.budget,
@@ -230,9 +258,28 @@ class Trip {
     }
   }
 
+  /// Vérifie si le voyage a des coordonnées géographiques valides
+  bool get hasCoordinates => latitude != null && longitude != null;
+
+  /// Vérifie si les coordonnées sont récentes (moins de 30 jours)
+  bool get hasRecentCoordinates {
+    if (!hasCoordinates || lastGeocodingUpdate == null) return false;
+    final thirtyDaysAgo = DateTime.now().subtract(const Duration(days: 30));
+    return lastGeocodingUpdate!.isAfter(thirtyDaysAgo);
+  }
+
+  /// Retourne un Map avec les coordonnées pour les services externes
+  Map<String, dynamic>? get coordinatesMap {
+    if (!hasCoordinates) return null;
+    return {
+      'lat': latitude!,
+      'lng': longitude!,
+    };
+  }
+
   @override
   String toString() {
-    return 'Trip(id: $id, title: $title, location: $location, status: $status)';
+    return 'Trip(id: $id, title: $title, location: $location, coordinates: ${hasCoordinates ? "($latitude, $longitude)" : "N/A"}, status: $status)';
   }
 
   @override