<?php
namespace Cron;
if (!defined('ABSPATH')) exit;
use DateTime;
use DateTimeImmutable;
use DateTimeZone;
use Exception;
use InvalidArgumentException;
use RuntimeException;
class CronExpression
{
const MINUTE = 0;
const HOUR = 1;
const DAY = 2;
const MONTH = 3;
const WEEKDAY = 4;
const YEAR = 5;
private $cronParts;
private $fieldFactory;
private $maxIterationCount = 1000;
private static $order = array(self::YEAR, self::MONTH, self::DAY, self::WEEKDAY, self::HOUR, self::MINUTE);
public static function factory($expression, FieldFactory $fieldFactory = null)
{
$mappings = array(
'@yearly' => '0 0 1 1 *',
'@annually' => '0 0 1 1 *',
'@monthly' => '0 0 1 * *',
'@weekly' => '0 0 * * 0',
'@daily' => '0 0 * * *',
'@hourly' => '0 * * * *'
);
if (isset($mappings[$expression])) {
$expression = $mappings[$expression];
}
return new static($expression, $fieldFactory ?: new FieldFactory());
}
public static function isValidExpression($expression)
{
try {
self::factory($expression);
} catch (InvalidArgumentException $e) {
return false;
}
return true;
}
public function __construct($expression, FieldFactory $fieldFactory)
{
$this->fieldFactory = $fieldFactory;
$this->setExpression($expression);
}
public function setExpression($value)
{
$this->cronParts = preg_split('/\s/', $value, -1, PREG_SPLIT_NO_EMPTY);
if (count($this->cronParts) < 5) {
throw new InvalidArgumentException(
$value . ' is not a valid CRON expression'
);
}
foreach ($this->cronParts as $position => $part) {
$this->setPart($position, $part);
}
return $this;
}
public function setPart($position, $value)
{
if (!$this->fieldFactory->getField($position)->validate($value)) {
throw new InvalidArgumentException(
'Invalid CRON field value ' . $value . ' at position ' . $position
);
}
$this->cronParts[$position] = $value;
return $this;
}
public function setMaxIterationCount($maxIterationCount)
{
$this->maxIterationCount = $maxIterationCount;
return $this;
}
public function getNextRunDate($currentTime = 'now', $nth = 0, $allowCurrentDate = false)
{
return $this->getRunDate($currentTime, $nth, false, $allowCurrentDate);
}
public function getPreviousRunDate($currentTime = 'now', $nth = 0, $allowCurrentDate = false)
{
return $this->getRunDate($currentTime, $nth, true, $allowCurrentDate);
}
public function getMultipleRunDates($total, $currentTime = 'now', $invert = false, $allowCurrentDate = false)
{
$matches = array();
for ($i = 0; $i < max(0, $total); $i++) {
try {
$matches[] = $this->getRunDate($currentTime, $i, $invert, $allowCurrentDate);
} catch (RuntimeException $e) {
break;
}
}
return $matches;
}
public function getExpression($part = null)
{
if (null === $part) {
return implode(' ', $this->cronParts);
} elseif (array_key_exists($part, $this->cronParts)) {
return $this->cronParts[$part];
}
return null;
}
public function __toString()
{
return $this->getExpression();
}
public function isDue($currentTime = 'now')
{
if ('now' === $currentTime) {
$currentDate = date('Y-m-d H:i');
$currentTime = strtotime($currentDate);
} elseif ($currentTime instanceof DateTime) {
$currentDate = clone $currentTime;
// Ensure time in 'current' timezone is used
$currentDate->setTimezone(new DateTimeZone(date_default_timezone_get()));
$currentDate = $currentDate->format('Y-m-d H:i');
$currentTime = strtotime($currentDate);
} elseif ($currentTime instanceof DateTimeImmutable) {
$currentDate = DateTime::createFromFormat('U', $currentTime->format('U'));
$currentDate->setTimezone(new DateTimeZone(date_default_timezone_get()));
$currentDate = $currentDate->format('Y-m-d H:i');
$currentTime = strtotime($currentDate);
} else {
$currentTime = new DateTime($currentTime);
$currentTime->setTime($currentTime->format('H'), $currentTime->format('i'), 0);
$currentDate = $currentTime->format('Y-m-d H:i');
$currentTime = $currentTime->getTimeStamp();
}
try {
return $this->getNextRunDate($currentDate, 0, true)->getTimestamp() == $currentTime;
} catch (Exception $e) {
return false;
}
}
protected function getRunDate($currentTime = null, $nth = 0, $invert = false, $allowCurrentDate = false)
{
if ($currentTime instanceof DateTime) {
$currentDate = clone $currentTime;
} elseif ($currentTime instanceof DateTimeImmutable) {
$currentDate = DateTime::createFromFormat('U', $currentTime->format('U'));
$currentDate->setTimezone($currentTime->getTimezone());
} else {
$currentDate = new DateTime($currentTime ?: 'now');
$currentDate->setTimezone(new DateTimeZone(date_default_timezone_get()));
}
$currentDate->setTime($currentDate->format('H'), $currentDate->format('i'), 0);
$nextRun = clone $currentDate;
$nth = (int) $nth;
// We don't have to satisfy * or null fields
$parts = array();
$fields = array();
foreach (self::$order as $position) {
$part = $this->getExpression($position);
if (null === $part || '*' === $part) {
continue;
}
$parts[$position] = $part;
$fields[$position] = $this->fieldFactory->getField($position);
}
// Set a hard limit to bail on an impossible date
for ($i = 0; $i < $this->maxIterationCount; $i++) {
foreach ($parts as $position => $part) {
$satisfied = false;
// Get the field object used to validate this part
$field = $fields[$position];
// Check if this is singular or a list
if (strpos($part, ',') === false) {
$satisfied = $field->isSatisfiedBy($nextRun, $part);
} else {
foreach (array_map('trim', explode(',', $part)) as $listPart) {
if ($field->isSatisfiedBy($nextRun, $listPart)) {
$satisfied = true;
break;
}
}
}
// If the field is not satisfied, then start over
if (!$satisfied) {
$field->increment($nextRun, $invert, $part);
continue 2;
}
}
// Skip this match if needed
if ((!$allowCurrentDate && $nextRun == $currentDate) || --$nth > -1) {
$this->fieldFactory->getField(0)->increment($nextRun, $invert, isset($parts[0]) ? $parts[0] : null);
continue;
}
return $nextRun;
}
// @codeCoverageIgnoreStart
throw new RuntimeException('Impossible CRON expression');
// @codeCoverageIgnoreEnd
}
}