import 'package:grouped_list/grouped_list.dart';
import 'package:intl/intl.dart';

/// Sorts [GroupedListView]'s group by newest group
int groupSortNewest(String a, String b, String locale) {
  // TODO: better sorting algorithm lol
  final yearA = RegExp(r'\d+').firstMatch(a);
  if (yearA == null) return 0;
  final yearB = RegExp(r'\d+').firstMatch(b);
  if (yearB == null) return 0;
  final compareYears = int.parse(yearB.group(0)!).compareTo(
    int.parse(yearA.group(0)!),
  );
  if (compareYears != 0) {
    return compareYears;
  }
  final months = List<String>.generate(
    12,
    (index) => DateFormat.MMMM(locale).format(
      DateTime(2023, index + 1),
    ),
  );
  final monthA = RegExp('[^0-9 ]+').firstMatch(a);
  if (monthA == null) return 0;
  final monthB = RegExp('[^0-9 ]+').firstMatch(b);
  if (monthB == null) return 0;
  return months.indexOf(monthB.group(0)!).compareTo(
        months.indexOf(monthA.group(0)!),
      );
}

/// Sorts [GroupedListView]'s group by oldest group
int groupSortOldest(String a, String b, String locale) {
  // TODO: better sorting algorithm lol
  final yearA = RegExp(r'\d+').firstMatch(a);
  if (yearA == null) return 0;
  final yearB = RegExp(r'\d+').firstMatch(b);
  if (yearB == null) return 0;
  final compareYears = int.parse(yearA.group(0)!).compareTo(
    int.parse(yearB.group(0)!),
  );
  if (compareYears != 0) {
    return compareYears;
  }
  final months = List<String>.generate(
    12,
    (index) => DateFormat.MMMM(locale).format(
      DateTime(2023, index + 1),
    ),
  );
  final monthA = RegExp('[^0-9 ]+').firstMatch(a);
  if (monthA == null) return 0;
  final monthB = RegExp('[^0-9 ]+').firstMatch(b);
  if (monthB == null) return 0;
  return months.indexOf(monthA.group(0)!).compareTo(
        months.indexOf(monthB.group(0)!),
      );
}