<?php
/**
* Day of month field. Allows: * , / - ? L W
*
* 'L' stands for "last" and specifies the last day of the month.
*
* The 'W' character is used to specify the weekday (Monday-Friday) nearest the
* given day. As an example, if you were to specify "15W" as the value for the
* day-of-month field, the meaning is: "the nearest weekday to the 15th of the
* month". So if the 15th is a Saturday, the trigger will fire on Friday the
* 14th. If the 15th is a Sunday, the trigger will fire on Monday the 16th. If
* the 15th is a Tuesday, then it will fire on Tuesday the 15th. However if you
* specify "1W" as the value for day-of-month, and the 1st is a Saturday, the
* trigger will fire on Monday the 3rd, as it will not 'jump' over the boundary
* of a month's days. The 'W' character can only be specified when the
* day-of-month is a single day, not a range or list of days.
*
* @author Michael Dowling <mtdowling@gmail.com>
*/
class CronExpression_DayOfMonthField extends CronExpression_AbstractField
{
/**
* Get the nearest day of the week for a given day in a month
*
* @param int $currentYear Current year
* @param int $currentMonth Current month
* @param int $targetDay Target day of the month
*
* @return DateTime Returns the nearest date
*/
private static function getNearestWeekday($currentYear, $currentMonth, $targetDay)
{
$tday = str_pad($targetDay, 2, '0', STR_PAD_LEFT);
$target = new DateTime("$currentYear-$currentMonth-$tday");
$currentWeekday = (int) $target->format('N');
if ($currentWeekday < 6) {
return $target;
}
$lastDayOfMonth = $target->format('t');
foreach (array(-1, 1, -2, 2) as $i) {
$adjusted = $targetDay + $i;
if ($adjusted > 0 && $adjusted <= $lastDayOfMonth) {
$target->setDate($currentYear, $currentMonth, $adjusted);
if ($target->format('N') < 6 && $target->format('m') == $currentMonth) {
return $target;
}
}
}
}
/**
* {@inheritdoc}
*/
public function isSatisfiedBy(DateTime $date, $value)
{
// ? states that the field value is to be skipped
if ($value == '?') {
return true;
}
$fieldValue = $date->format('d');
// Check to see if this is the last day of the month
if ($value == 'L') {
return $fieldValue == $date->format('t');
}
// Check to see if this is the nearest weekday to a particular value
if (strpos($value, 'W')) {
// Parse the target day
$targetDay = substr($value, 0, strpos($value, 'W'));
// Find out if the current day is the nearest day of the week
return $date->format('j') == self::getNearestWeekday(
$date->format('Y'),
$date->format('m'),
$targetDay
)->format('j');
}
return $this->isSatisfied($date->format('d'), $value);
}
/**
* {@inheritdoc}
*/
public function increment(DateTime $date, $invert = false)
{
if ($invert) {
$date->modify('previous day');
$date->setTime(23, 59);
} else {
$date->modify('next day');
$date->setTime(0, 0);
}
return $this;
}
/**
* {@inheritdoc}
*/
public function validate($value)
{
return (bool) preg_match('/[\*,\/\-\?LW0-9A-Za-z]+/', $value);
}
}