parseDate method
Implementation
DateTime? parseDate({required String date}) {
if (date.isEmpty) return null;
final parts = date.split("-");
if (parts.length != 3) return null;
final day = int.tryParse(parts[0]);
final month = int.tryParse(parts[1]);
final year = int.tryParse(parts[2]);
if (day == null || month == null || year == null) return null;
return DateTime(year, month, day);
}