def _parse_rruleset(rruleset):
        """Convert from iCal rrule to Remind recurrence syntax"""
        # pylint: disable=protected-access

        if rruleset._rrule[0]._freq == 0:
            return []

        rep = []
        if rruleset._rrule[0]._byweekday and len(rruleset._rrule[0]._byweekday) > 1:
            rep.append('*1')
        elif rruleset._rrule[0]._freq == rrule.DAILY:
            rep.append('*%d' % rruleset._rrule[0]._interval)
        elif rruleset._rrule[0]._freq == rrule.WEEKLY:
            rep.append('*%d' % (7 * rruleset._rrule[0]._interval))
        else:
            return Remind._parse_rdate(rruleset._rrule[0])

        if rruleset._rrule[0]._byweekday and len(rruleset._rrule[0]._byweekday) > 1:
            daynums = set(range(7)) - set(rruleset._rrule[0]._byweekday)
            weekdays = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
            days = [weekdays[day] for day in daynums]
            rep.append('SKIP OMIT %s' % ' '.join(days))

        if rruleset._rrule[0]._until:
            rep.append(rruleset._rrule[0]._until.strftime('UNTIL %b %d %Y').replace(' 0', ' '))
        elif rruleset._rrule[0]._count:
            rep.append(rruleset[-1].strftime('UNTIL %b %d %Y').replace(' 0', ' '))

        return rep