tryParseDuration function

Duration? tryParseDuration(String? v, [ Duration? def ])

Implementation

Duration? tryParseDuration(String? v, [Duration? def]) {
  if (v == null || v.isEmpty) return def;

  var n = int.tryParse(v);
  if (n != null) {
    return Duration(milliseconds: n);
  }

  var s = v.toLowerCase().trim().replaceAll(RegExp(r'\s+'), '');

  n = int.tryParse(s.replaceAll(RegExp(r'\D+'), ''));

  if (n == null) return def;
  if (n == 0) return Duration();

  if (s.endsWith("h") ||
      s.endsWith("hr") ||
      s.endsWith("hs") ||
      s.endsWith("hour") ||
      s.endsWith("hours")) {
    return Duration(hours: n);
  } else if (s.endsWith("ms") ||
      s.endsWith("milliseconds") ||
      s.endsWith("millisecond")) {
    return Duration(milliseconds: n);
  } else if (s.endsWith("min") ||
      s.endsWith("minutes") ||
      s.endsWith("minute")) {
    return Duration(minutes: n);
  } else if (s.endsWith("sec") ||
      s.endsWith("seconds") ||
      s.endsWith("second") ||
      s.endsWith("s")) {
    return Duration(seconds: n);
  } else {
    return def;
  }
}