/application/libraries/CronParser.php

<?php /* $Id: CronParser.php,v 1.7 2005/09/12 01:04:05 ns Exp $ */



/**####################################################################################################**\

   Version: V1.01

   Release Date: 12 Sep 2005

   Licence: GPL

   By: Nikol S

   Please send bug reports to ns@eyo.com.au

\**####################################################################################################**/



/* This class is based on the concept in the CronParser class written by Mick Sear http://www.ecreate.co.uk

 * The following functions are direct copies from or based on the original class:

 * getLastRan(), getDebug(), debug(), expand_ranges()

 *

 * Who can use this class?

 * This class is idea for people who can not use the traditional Unix cron through shell.

 * One way of using is embedding the calling script in a web page which is often visited.

 * The script will work out the last due time, by comparing with run log timestamp. The scrip

 * will envoke any scripts needed to run, be it deleting older table records, or updating prices.

 * It can parse the same cron string used by Unix.

 */



/* Usage example:



$cron_str0 = "0,12,30-51 3,21-23,10 1-25 9-12,1 0,3-7";

require_once("CronParser.php");

$cron = new CronParser();

$cron->calcLastRan($cron_str0);

// $cron->getLastRanUnix() returns an Unix timestamp

echo "Cron '$cron_str0' last due at: " . date('r', $cron->getLastRanUnix()) . "<p>";

// $cron->getLastRan() returns last due time in an array

print_r($cron->getLastRan());

echo "Debug:<br>" . nl2br($cron->getDebug());



$cron_str1 = "3 12 * * *";

if ($cron->calcLastRan($cron_str1))

{

   echo "<p>Cron '$cron_str1' last due at: " . date('r', $cron->getLastRanUnix()) . "<p>";

   print_r($cron->getLastRan());

}

else

{

   echo "Error parsing";

}

echo "Debug:<br>" . nl2br($cron->getDebug());



 *#######################################################################################################

 */



class CronParser

{



 	var $bits = Array(); //exploded String like 0 1 * * *

 	var $now = Array();	//Array of cron-style entries for time()

 	var $lastRan; 		//Timestamp of last ran time.

 	var $taken;

 	var $debug;

	var $year;

	var $month;

	var $day;

	var $hour;

	var $minute;

	var $minutes_arr = array();	//minutes array based on cron string

	var $hours_arr = array();	//hours array based on cron string

	var $months_arr = array();	//months array based on cron string



	function getLastRan()

	{

		return explode(",", strftime("%M,%H,%d,%m,%w,%Y", $this->lastRan)); //Get the values for now in a format we can use

	}



	function getLastRanUnix()

	{

		return $this->lastRan;

	}



	function getDebug()

	{

 		return $this->debug;

	}



	function debug($str)

	{

		if (is_array($str))

		{

			$this->debug .= "\nArray: ";

			foreach($str as $k=>$v)

			{

				$this->debug .= "$k=>$v, ";

			}



		}

		else

		{

			$this->debug .= "\n$str";

		}

		//echo nl2br($this->debug);

	}



	/**

	 * Assumes that value is not *, and creates an array of valid numbers that

	 * the string represents.  Returns an array.

	 */

	function expand_ranges($str)

	{

		if (strstr($str,  ","))

		{

			$arParts = explode(',', $str);

			foreach ($arParts AS $part)

			{

				if (strstr($part, '-'))

				{

					$arRange = explode('-', $part);

					for ($i = $arRange[0]; $i <= $arRange[1]; $i++)

					{

						$ret[] = $i;

					}

				}

				else

				{

					$ret[] = $part;

				}

			}

		}

		elseif (strstr($str,  '-'))

		{

			$arRange = explode('-', $str);

			for ($i = $arRange[0]; $i <= $arRange[1]; $i++)

			{

				$ret[] = $i;

			}

		}

		else

		{

			$ret[] = $str;

		}

		$ret = array_unique($ret);

		sort($ret);

		return $ret;

	}



	function daysinmonth($month, $year)

	{

		return date('t', mktime(0, 0, 0, $month, 1, $year));

	}



	/**

	 *  Calculate the last due time before this moment

	 */

	function calcLastRan($string)

	{



 		$tstart = microtime();

		$this->debug = "";

		$this->lastRan = 0;

		$this->year = NULL;

		$this->month = NULL;

		$this->day = NULL;

		$this->hour = NULL;

		$this->minute = NULL;

		$this->hours_arr = array();

		$this->minutes_arr = array();

		$this->months_arr = array();



		$string = preg_replace('/[\s]{2,}/', ' ', $string);



		if (preg_match('/[^-,* \\d]/', $string) !== 0)

		{

			$this->debug("Cron String contains invalid character");

			return false;

		}



		$this->debug("<b>Working on cron schedule: $string</b>");

 		$this->bits = @explode(" ", $string);



		if (count($this->bits) != 5)

		{

			$this->debug("Cron string is invalid. Too many or too little sections after explode");

			return false;

		}



		//put the current time into an array

		$t = strftime("%M,%H,%d,%m,%w,%Y", time());

		$this->now = explode(",", $t);



		$this->year = $this->now[5];



		$arMonths = $this->_getMonthsArray();



		do

		{

			$this->month = array_pop($arMonths);

		}

		while ($this->month > $this->now[3]);



		if ($this->month === NULL)

		{

			$this->year = $this->year - 1;

			$this->debug("Not due within this year. So checking the previous year " . $this->year);

			$arMonths = $this->_getMonthsArray();

			$this->_prevMonth($arMonths);

		}

		elseif ($this->month == $this->now[3]) //now Sep, month = array(7,9,12)

		{

			$this->debug("Cron is due this month, getting days array.");

			$arDays = $this->_getDaysArray($this->month, $this->year);



			do

			{

				$this->day = array_pop($arDays);

			}

			while ($this->day > $this->now[2]);



			if ($this->day === NULL)

			{

				$this->debug("Smallest day is even greater than today");

				$this->_prevMonth($arMonths);

			}

			elseif ($this->day == $this->now[2])

			{

				$this->debug("Due to run today");

				$arHours = $this->_getHoursArray();



				do

				{

					$this->hour = array_pop($arHours);

				}

				while ($this->hour > $this->now[1]);



				if ($this->hour === NULL) // now =2, arHours = array(3,5,7)

				{

					$this->debug("Not due this hour and some earlier hours, so go for previous day");

					$this->_prevDay($arDays, $arMonths);

				}

				elseif ($this->hour < $this->now[1]) //now =2, arHours = array(1,3,5)

				{

					$this->minute = $this->_getLastMinute();

				}

				else // now =2, arHours = array(1,2,5)

				{

					$this->debug("Due this hour");

					$arMinutes = $this->_getMinutesArray();

					do

					{

						$this->minute = array_pop($arMinutes);

					}

					while ($this->minute > $this->now[0]);



					if ($this->minute === NULL)

					{

						$this->debug("Not due this minute, so go for previous hour.");

						$this->_prevHour($arHours, $arDays, $arMonths);

					}

					else

					{

						$this->debug("Due this very minute or some earlier minutes before this moment within this hour.");

					}

				}

			}

			else

			{

				$this->debug("Cron was due on " . $this->day . " of this month");

				$this->hour = $this->_getLastHour();

				$this->minute = $this->_getLastMinute();

			}

		}

		else //now Sep, arrMonths=array(7, 10)

		{

			$this->debug("Cron was due before this month. Previous month is: " . $this->year . '-' . $this->month);

			$this->day = $this->_getLastDay($this->month, $this->year);

			if ($this->day === NULL)

			{

				//No scheduled date within this month. So we will try the previous month in the month array

				$this->_prevMonth($arMonths);

			}

			else

			{

				$this->hour = $this->_getLastHour();

				$this->minute = $this->_getLastMinute();

			}

		}



		$tend = microtime();

		$this->taken = $tend - $tstart;

		$this->debug("Parsing $string taken " . $this->taken . " seconds");



		//if the last due is beyond 1970

		if ($this->minute === NULL)

		{

			$this->debug("Error calculating last due time");

			return false;

		}

		else

		{

			$this->debug("LAST DUE: " . $this->hour . ":" . $this->minute . " on " . $this->day . "/" . $this->month . "/" . $this->year);

			$this->lastRan = mktime($this->hour, $this->minute, 0, $this->month, $this->day, $this->year);

			return true;

		}

	}



	//get the due time before current month

	function _prevMonth($arMonths)

	{

		$this->month = array_pop($arMonths);

		if ($this->month === NULL)

		{

			$this->year = $this->year -1;

			if ($this->year <= 1970)

			{

				$this->debug("Can not calculate last due time. At least not before 1970..");

			}

			else

			{

				$this->debug("Have to go for previous year " . $this->year);

				$arMonths = $this->_getMonthsArray();

				$this->_prevMonth($arMonths);

			}

		}

		else

		{

			$this->debug("Getting the last day for previous month: " . $this->year . '-' . $this->month);

			$this->day = $this->_getLastDay($this->month, $this->year);



			if ($this->day === NULL)

			{

				//no available date schedule in this month

				$this->_prevMonth($arMonths);

			}

			else

			{

				$this->hour = $this->_getLastHour();

				$this->minute = $this->_getLastMinute();

			}

		}



	}



	//get the due time before current day

	function _prevDay($arDays, $arMonths)

	{

		$this->debug("Go for the previous day");

		$this->day = array_pop($arDays);

		if ($this->day === NULL)

		{

			$this->debug("Have to go for previous month");

			$this->_prevMonth($arMonths);

		}

		else

		{

			$this->hour = $this->_getLastHour();

			$this->minute = $this->_getLastMinute();

		}

	}



	//get the due time before current hour

	function _prevHour($arHours, $arDays, $arMonths)

	{

		$this->debug("Going for previous hour");

		$this->hour = array_pop($arHours);

		if ($this->hour === NULL)

		{

			$this->debug("Have to go for previous day");

			$this->_prevDay($arDays, $arMonths);

		}

		else

		{

			$this->minute = $this->_getLastMinute();

		}

	}



	//not used at the moment

	function _getLastMonth()

	{

		$months = $this->_getMonthsArray();

		$month = array_pop($months);



		return $month;

	}



	function _getLastDay($month, $year)

	{

		//put the available days for that month into an array

		$days = $this->_getDaysArray($month, $year);

		$day = array_pop($days);



		return $day;

	}



	function _getLastHour()

	{

		$hours = $this->_getHoursArray();

		$hour = array_pop($hours);



		return $hour;

	}



	function _getLastMinute()

	{

		$minutes = $this->_getMinutesArray();

		$minute = array_pop($minutes);



		return $minute;

	}



	//remove the out of range array elements. $arr should be sorted already and does not contain duplicates

	function _sanitize ($arr, $low, $high)

	{

		$count = count($arr);

		for ($i = 0; $i <= ($count - 1); $i++)

		{

			if ($arr[$i] < $low)

			{

				$this->debug("Remove out of range element. {$arr[$i]} is outside $low - $high");

				unset($arr[$i]);

			}

			else

			{

				break;

			}

		}



		for ($i = ($count - 1); $i >= 0; $i--)

		{

			if ($arr[$i] > $high)

			{

				$this->debug("Remove out of range element. {$arr[$i]} is outside $low - $high");

				unset ($arr[$i]);

			}

			else

			{

				break;

			}

		}



		//re-assign keys

		sort($arr);

		return $arr;

	}



	//given a month/year, list all the days within that month fell into the week days list.

	function _getDaysArray($month, $year = 0)

	{

		if ($year == 0)

		{

			$year = $this->year;

		}



		$days = array();



		//return everyday of the month if both bit[2] and bit[4] are '*'

		if ($this->bits[2] == '*' AND $this->bits[4] == '*')

		{

			$days = $this->getDays($month, $year);

		}

		else

		{

			//create an array for the weekdays

			if ($this->bits[4] == '*')

			{

				for ($i = 0; $i <= 6; $i++)

				{

					$arWeekdays[] = $i;

				}

			}

			else

			{

				$arWeekdays = $this->expand_ranges($this->bits[4]);

				$arWeekdays = $this->_sanitize($arWeekdays, 0, 7);



				//map 7 to 0, both represents Sunday. Array is sorted already!

				if (in_array(7, $arWeekdays))

				{

					if (in_array(0, $arWeekdays))

					{

						array_pop($arWeekdays);

					}

					else

					{

						$tmp[] = 0;

						array_pop($arWeekdays);

						$arWeekdays = array_merge($tmp, $arWeekdays);

					}

				}

			}

			$this->debug("Array for the weekdays");

			$this->debug($arWeekdays);



			if ($this->bits[2] == '*')

			{

				$daysmonth = $this->getDays($month, $year);

			}

			else

			{

				$daysmonth = $this->expand_ranges($this->bits[2]);

				// so that we do not end up with 31 of Feb

				$daysinmonth = $this->daysinmonth($month, $year);

				$daysmonth = $this->_sanitize($daysmonth, 1, $daysinmonth);

			}



			//Now match these days with weekdays

			foreach ($daysmonth AS $day)

			{

				$wkday = date('w', mktime(0, 0, 0, $month, $day, $year));

				if (in_array($wkday, $arWeekdays))

				{

					$days[] = $day;

				}

			}

		}

		$this->debug("Days array matching weekdays for $year-$month");

		$this->debug($days);

		return $days;

	}



	//given a month/year, return an array containing all the days in that month

	function getDays($month, $year)

	{

		$daysinmonth = $this->daysinmonth($month, $year);

		$this->debug("Number of days in $year-$month : $daysinmonth");

		$days = array();

		for ($i = 1; $i <= $daysinmonth; $i++)

		{

			$days[] = $i;

		}

		return $days;

	}



	function _getHoursArray()

	{

		if (empty($this->hours_arr))

		{

			$hours = array();



			if ($this->bits[1] == '*')

			{

				for ($i = 0; $i <= 23; $i++)

				{

					$hours[] = $i;

				}

			}

			else

			{

				$hours = $this->expand_ranges($this->bits[1]);

				$hours = $this->_sanitize($hours, 0, 23);

			}



			$this->debug("Hour array");

			$this->debug($hours);

			$this->hours_arr = $hours;

		}

		return $this->hours_arr;

	}



	function _getMinutesArray()

	{

		if (empty($this->minutes_arr))

		{

			$minutes = array();



			if ($this->bits[0] == '*')

			{

				for ($i = 0; $i <= 60; $i++)

				{

					$minutes[] = $i;

				}

			}

			else

			{

				$minutes = $this->expand_ranges($this->bits[0]);

				$minutes = $this->_sanitize($minutes, 0, 59);

			}

			$this->debug("Minutes array");

			$this->debug($minutes);

			$this->minutes_arr = $minutes;

		}

		return $this->minutes_arr;

	}



	function _getMonthsArray()

	{

		if (empty($this->months_arr))

		{

			$months = array();

			if ($this->bits[3] == '*')

			{

				for ($i = 1; $i <= 12; $i++)

				{

					$months[] = $i;

				}

			}

			else

			{

				$months = $this->expand_ranges($this->bits[3]);

				$months = $this->_sanitize($months, 1, 12);

			}

			$this->debug("Months array");

			$this->debug($months);

			$this->months_arr = $months;

		}

		return $this->months_arr;

	}



}

?>