class FuelEntry {
  final String id;
  final String vehicleId;
  final DateTime date;
  final double gallons;
  final double pricePerGallon;
  final double totalCost;
  final String? receiptImagePath;
  final String? receiptDriveFileId;
  final DateTime updatedAt;

  FuelEntry({
    required this.id,
    required this.vehicleId,
    required this.date,
    required this.gallons,
    required this.pricePerGallon,
    required this.totalCost,
    required this.updatedAt,
    this.receiptImagePath,
    this.receiptDriveFileId,
  });

  /// True once the receipt photo has been uploaded to Drive and the local
  /// copy removed. Viewing it then requires downloading it on demand.
  bool get isReceiptUploadedToDrive =>
      receiptImagePath == null && receiptDriveFileId != null;

  /// True while a receipt photo exists only locally and still needs to be
  /// uploaded next sync.
  bool get hasPendingLocalReceipt => receiptImagePath != null;

  FuelEntry copyWith({
    String? receiptImagePath,
    String? receiptDriveFileId,
    DateTime? updatedAt,
    bool clearReceiptImagePath = false,
  }) {
    return FuelEntry(
      id: id,
      vehicleId: vehicleId,
      date: date,
      gallons: gallons,
      pricePerGallon: pricePerGallon,
      totalCost: totalCost,
      updatedAt: updatedAt ?? this.updatedAt,
      receiptImagePath:
          clearReceiptImagePath ? null : (receiptImagePath ?? this.receiptImagePath),
      receiptDriveFileId: receiptDriveFileId ?? this.receiptDriveFileId,
    );
  }

  Map<String, dynamic> toJson() => {
        'id': id,
        'vehicleId': vehicleId,
        'date': date.toIso8601String(),
        'gallons': gallons,
        'pricePerGallon': pricePerGallon,
        'totalCost': totalCost,
        'receiptImagePath': receiptImagePath,
        'receiptDriveFileId': receiptDriveFileId,
        'updatedAt': updatedAt.toIso8601String(),
      };

  factory FuelEntry.fromJson(Map<String, dynamic> 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?,
        receiptDriveFileId: json['receiptDriveFileId'] as String?,
        updatedAt: json['updatedAt'] != null
            ? DateTime.parse(json['updatedAt'] as String)
            : DateTime.fromMillisecondsSinceEpoch(0),
      );
}