class FuelEntry { final String id; final String vehicleId; final DateTime date; final double gallons; final double pricePerGallon; final double totalCost; final String? receiptImagePath; FuelEntry({ required this.id, required this.vehicleId, required this.date, required this.gallons, required this.pricePerGallon, required this.totalCost, this.receiptImagePath, }); Map toJson() => { 'id': id, 'vehicleId': vehicleId, 'date': date.toIso8601String(), 'gallons': gallons, 'pricePerGallon': pricePerGallon, 'totalCost': totalCost, 'receiptImagePath': receiptImagePath, }; factory FuelEntry.fromJson(Map json) => FuelEntry( id: json['id'] as String, vehicleId: json['vehicleId'] as String, date: DateTime.parse(json['date'] as String), gallons: (json['gallons'] as num).toDouble(), pricePerGallon: (json['pricePerGallon'] as num).toDouble(), totalCost: (json['totalCost'] as num).toDouble(), receiptImagePath: json['receiptImagePath'] as String?, ); }