public function getPreviousDate()
{
$date = $this->getDate();
$startDate = $this->obj('StartDate');
if ($date->format('Y') < $startDate->format('Y') || $date->format('n') < $startDate->format('n') || $date->format('j') <= $startDate->format('j')) {
return;
}
$previousDate = new SS_DateTime('PreviousDate');
$previousDate->setValue($date->getValue());
do {
$previousDate->setValue($previousDate->day_before($previousDate->format('Y'), $previousDate->format('n'), $previousDate->format('j')));
} while ($previousDate->format('N') >= 6);
// Skip past weekends.
// If, after we skipped the weekend, we've shot past the start of sprint, then return.
if ($previousDate->format('Y') < $startDate->format('Y') || $previousDate->format('n') < $startDate->format('n') || $previousDate->format('j') < $startDate->format('j')) {
return;
}
return $previousDate;
}