format function

String format(DateTime date, { String locale, DateTime clock, bool allowFromNow, })

Formats provided date to a fuzzy time like 'a moment ago'

• If locale is passed will look for message for that locale, if you want to add or override locales use setLocaleMessages. Defaults to 'en'
• If clock is passed this will be the point of reference for calculating the elapsed time. Defaults to DateTime.now()
• If allowFromNow is passed, format will use the From prefix, ie. a date 5 minutes from now in 'en' locale will display as "5 minutes from now"

Implementation

String format(DateTime date,
    {String locale, DateTime clock, bool allowFromNow}) {
  final _locale = locale ?? 'en';
  final _allowFromNow = allowFromNow ?? false;
  final messages = _lookupMessagesMap[_locale] ?? EnMessages();
  final _clock = clock ?? DateTime.now();
  var elapsed = _clock.millisecondsSinceEpoch - date.millisecondsSinceEpoch;

  String prefix, suffix;

  if (_allowFromNow && elapsed < 0) {
    elapsed = date.isBefore(_clock) ? elapsed : elapsed.abs();
    prefix = messages.prefixFromNow();
    suffix = messages.suffixFromNow();
  } else {
    prefix = messages.prefixAgo();
    suffix = messages.suffixAgo();
  }

  final num seconds = elapsed / 1000;
  final num minutes = seconds / 60;
  final num hours = minutes / 60;
  final num days = hours / 24;
  final num months = days / 30;
  final num years = days / 365;

  String result;
  if (seconds < 45) {
    result = messages.lessThanOneMinute(seconds.round());
  } else if (seconds < 90) {
    result = messages.aboutAMinute(minutes.round());
  } else if (minutes < 45) {
    result = messages.minutes(minutes.round());
  } else if (minutes < 90) {
    result = messages.aboutAnHour(minutes.round());
  } else if (hours < 24) {
    result = messages.hours(hours.round());
  } else if (hours < 48) {
    result = messages.aDay(hours.round());
  } else if (days < 30) {
    result = messages.days(days.round());
  } else if (days < 60) {
    result = messages.aboutAMonth(days.round());
  } else if (days < 365) {
    result = messages.months(months.round());
  } else if (years < 2) {
    result = messages.aboutAYear(months.round());
  } else {
    result = messages.years(years.round());
  }

  return [prefix, result, suffix]
      .where((str) => str != null && str.isNotEmpty)
      .join(messages.wordSeparator());
}