Method validateDate

public static function validateDate($date)
{
    $format = 'Y-m-d H:i:s';
    $dateTime = DateTime::createFromFormat($format, $date);
    if ($dateTime instanceof DateTime && $dateTime->format('Y-m-d H:i:s') == $date) {
        return $dateTime->getTimestamp();
    }
    return false;
}