bool DateComponents::setMillisecondsSinceEpochForWeek(double ms) {
m_type = Invalid;
if (!std::isfinite(ms))
return false;
ms = round(ms);
m_year = msToYear(ms);
if (m_year < minimumYear() || m_year > maximumYear())
return false;
int yearDay = dayInYear(ms, m_year);
int offset = offsetTo1stWeekStart(m_year);
if (yearDay < offset) {
// The day belongs to the last week of the previous year.
m_year--;
if (m_year <= minimumYear())
return false;
m_week = maxWeekNumberInYear();
} else {
m_week = ((yearDay - offset) / 7) + 1;
if (m_week > maxWeekNumberInYear()) {
m_year++;
m_week = 1;
}
if (m_year > maximumYear() ||
(m_year == maximumYear() && m_week > maximumWeekInMaximumYear))
return false;
}
m_type = Week;
return true;
}
double DateComponents::millisecondsSinceEpoch() const
{
switch (m_type) {
case Date:
return dateToDaysFrom1970(m_year, m_month, m_monthDay) * msPerDay;
case DateTime:
case DateTimeLocal:
return dateToDaysFrom1970(m_year, m_month, m_monthDay) * msPerDay + millisecondsSinceEpochForTime();
case Month:
return dateToDaysFrom1970(m_year, m_month, 1) * msPerDay;
case Time:
return millisecondsSinceEpochForTime();
case Week:
return (dateToDaysFrom1970(m_year, 0, 1) + offsetTo1stWeekStart(m_year) + (m_week - 1) * 7) * msPerDay;
case Invalid:
break;
}
ASSERT_NOT_REACHED();
return invalidMilliseconds();
}