import 'package:intl/intl.dart';

final _money = NumberFormat.currency(locale: 'en_US', symbol: r'$');
final _time = DateFormat('h:mm a');
final _dayFull = DateFormat('EEEE d MMMM');
final _dayShort = DateFormat('EEE, d MMM yyyy');
final _monthYear = DateFormat('MMMM yyyy');

abstract final class Fmt {
  static String money(num v) => _money.format(v);

  static String time(DateTime d) => _time.format(d);

  static String window(DateTime start, DateTime end) =>
      '${_time.format(start)} - ${_time.format(end)}';

  static String dayFull(DateTime d) => _dayFull.format(d);

  static String dayShort(DateTime d) => _dayShort.format(d);

  static String monthYear(DateTime d) => _monthYear.format(d);

  /// `5h 48m`, the form used on every hours figure.
  static String duration(Duration d) {
    final h = d.inHours;
    final m = d.inMinutes.remainder(60);
    if (h == 0) return '${m}m';
    return '${h}h ${m.toString().padLeft(2, '0')}m';
  }

  /// `05:48:12`, for the running clock-in timer.
  static String stopwatch(Duration d) {
    final h = d.inHours.toString().padLeft(2, '0');
    final m = d.inMinutes.remainder(60).toString().padLeft(2, '0');
    final s = d.inSeconds.remainder(60).toString().padLeft(2, '0');
    return '$h:$m:$s';
  }

  /// A human countdown to a shift start: `in 41 min`, `in 3 hr`, `tomorrow`.
  static String untilStart(DateTime start, {DateTime? now}) {
    final from = now ?? DateTime.now();
    final diff = start.difference(from);
    if (diff.isNegative) return 'Started';
    if (diff.inMinutes < 60) return 'In ${diff.inMinutes} min';
    if (diff.inHours < 24) return 'In ${diff.inHours} hr';
    return 'In ${diff.inDays} d';
  }

  static bool sameDay(DateTime a, DateTime b) =>
      a.year == b.year && a.month == b.month && a.day == b.day;
}