/instances/application/libraries/CronParser.php

<?php

/**

 * CronParser library.

 * Reads Cron schedule from database

 * Determines if scheduled item has already been ran

 * Courtesy of Mick Sear (eCreate)

 * 

 * @package    Proximity

 * @author     Ushahidi Team

 * @copyright  (c) 2008 Ushahidi Team

 * @license    http://www.ushahidi.com/license.html

 */



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;

	

 	

 	function CronParser($string){

 		$tstart = microtime();

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

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

 		$this->getNow(); 		

 		$this->calcLastRan();

 		$tend = microtime();

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

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

 		

 	}

 	

 	function getNow(){

		$t = strftime("%M,%H,%d,%m,%w,%Y", time()); //Get the values for now in a format we can use

		$this->now = explode(",", $t); //Make this an array

		//$this->debug($this->now);

 	}

 	

 	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 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);

		

	} 	

 	



	function getExtremeMonth($extreme){



		if ($extreme == "END"){

			$year = $this->now[5] - 1;

		} else {

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

		}

		

		//Now determine start or end month in the last year

		if ($this->bits[3] == "*" && $extreme == "END"){//Check month format

			$month = 12;			

		} else if ($this->bits[3] == "*" && $extreme == "START"){

			$month = 1;

		} else {

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

			if ($extreme == "END"){

				sort($months);

			} else {

				rsort($months);

			}

			$month = array_pop($months);

		}

		

		//Now determine the latest day in the specified month

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

		$this->debug("Got day $day for $extreme of $month, $year");

		$hour = $this->getExtremeHour($extreme);

		$minute = $this->getExtremeMinute($extreme);

		

		return mktime($hour, $minute, 0, $month, $day, $year);

	}

	

	/**

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

	 * the string represents.  Returns an array.

	 */

	function expand_ranges($str){

		//$this->debug("Expanding $str");

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

			$tmp1 = explode(",", $str);

			//$this->debug($tmp1);

			$count = count($tmp1);

			for ($i=0;$i<$count;$i++){//Loop through each comma-separated value

				if (strstr($tmp1[$i],  "-")){ //If there's a range in this place, expand that too

					$tmp2 = explode("-", $tmp1[$i]);

					//$this->debug("Range:");

					//$this->debug($tmp2);

					for ($j=$tmp2[0];$j<=$tmp2[1];$j++){

						$ret[] = $j;

					}

				} else {//Otherwise, just add the value

					$ret[] = $tmp1[$i];

				}

			} 

		} else if (strstr($str,  "-")){//There might only be a range, no comma sep values at all.  Just loop these

			$range = explode("-", $str);

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

				$ret[] = $i;

			}

		} else {//Otherwise, it's a single value

			$ret[] = $str;

		}

		//$this->debug($ret);

		return $ret;

	}

	

	/**

	 * Given a string representation of a set of weekdays, returns an array of

	 * possible dates.

	 */

	function getWeekDays($str, $month, $year){

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

		

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

			$tmp1 = explode(",", $str);

			$count = count($tmp1);

			for ($i=0;$i<$count;$i++){//Loop through each comma-separated value

				if (strstr($tmp1[$i],  "-")){ //If there's a range in this place, expand that too

					$tmp2 = explode("-", $tmp1[$i]);

					

					for ($j=$start;$j<=$tmp2[1];$j++){

						for ($n=1;$n<=$daysInMonth;$n++){

			 				if ($j == jddayofweek(gregoriantojd ( $month, $n, $year),0)){

			 					$ret[] = $n;

			 				}			 				

			 			}

					}

				} else {//Otherwise, just add the value

					for ($n=1;$n<=$daysInMonth;$n++){

	 					if ($tmp1[$i] == jddayofweek(gregoriantojd ( $month, $n, $year),0)){

	 						$ret[] = $n;

	 					}			 				

	 				}

				}

			} 

		} else if (strstr($str,  "-")){//There might only be a range, no comma sep values at all.  Just loop these

			$range = explode("-", $str);

			for ($i=$start;$i<=$range[1];$i++){

				for ($n=1;$n<=$daysInMonth;$n++){

	 				if ($i == jddayofweek(gregoriantojd ( $month, $n, $year),0)){

	 					$ret[] = $n;

	 				}			 				

	 			}

			}

		} else {//Otherwise, it's a single value

			for ($n=1;$n<=$daysInMonth;$n++){				

				if ($str == jddayofweek(gregoriantojd ( $month, $n, $year),0)){

					$ret[] = $n;

				}			 				

			}

		}

		

		return $ret;		

	}

	

 	function daysinmonth($month, $year){

       if(checkdate($month, 31, $year)) return 31;

       if(checkdate($month, 30, $year)) return 30;

       if(checkdate($month, 29, $year)) return 29;

       if(checkdate($month, 28, $year)) return 28;

       return 0; // error

   }	

   

   /**

    * Get the timestamp of the last ran time.

    */

   function calcLastRan(){

		$now = time();



		if ($now < $this->getExtremeMonth("START")){

			//The cron isn't due to have run this year yet.  Getting latest last year

			$this->debug("Last ran last year");

			$tsLatestLastYear = $this->getExtremeMonth("END");	

			

			$this->debug("Timestamp of latest scheduled time last year is ".$tsLatestLastYear);

			$this->lastRan = $tsLatestLastYear;

			

			$year = date("Y", $this->lastRan);

			$month = date("m", $this->lastRan);

			$day = date("d", $this->lastRan);

			$hour = date("h", $this->lastRan);

			$minute = date("i", $this->lastRan);		

			

			

		} else { //Cron was due to run this year.  Determine when it was last due

			$this->debug("Cron was due to run earlier this year");

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

	   		

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

   			if (!in_array($this->now[3], $arMonths) && $this->bits[3] != "*"){//Not due to run this month.  Get latest of last month

   				$this->debug("Cron was not due to run this month at all. This month is ".$this->now[3]);

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

   				$this->debug($arMonths);

   				sort($arMonths);

				do{

					$month = array_pop($arMonths);

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

				$day = $this->getExtremeOfMonth($month, $this->now[5], "END");

	   			$hour = $this->getExtremeHour("END");

	   			$minute = $this->getExtremeMinute("END");	

   			} else if ($now < $this->getExtremeOfMonth($this->now[3], $this->now[5], "START")){ //It's due in this month, but not yet.

   				$this->debug("It's due in this month, but not yet.");

   				sort($arMonths);

				do{

					$month = array_pop($arMonths);

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

				$day = $this->getExtremeOfMonth($month, $this->now[5], "END");

	   			$hour = $this->getExtremeHour("END");

	   			$minute = $this->getExtremeMinute("END");

   			} else {//It has been due this month already

   				$this->debug("Cron has already been due to run this month (".$month = $this->now[3].")");

	   			$month = $this->now[3];		

	   			$this->debug("Getting days array");

	   			$days = $this->getDaysArray($this->now[3]);

	   			

	   			if (!in_array($this->now[2], $days)){

	   				$this->debug("Today not in the schedule.  Getting latest last due day");

	   				//No - Get latest last scheduled day   				

	   				sort($days);

	   				do{

	   					$day = array_pop($days);

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

	   				

	   				$hour = $this->getExtremeHour("END");

	   				$minute = $this->getExtremeMinute("END");

	   				

	   			} else if($this->now[1] < $this->getExtremeHour("START")){//Not due to run today yet

	   				$this->debug("Cron due today, but not yet.  Getting latest on last day");

	   				sort($days);

	   				do{

	   					$day = array_pop($days);

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

	   				

	   				$hour = $this->getExtremeHour("END");

	   				$minute = $this->getExtremeMinute("END");

	   			} else {

	   				$this->debug("Cron has already been due to run today");

	   				$day = $this->now[2];

	   				//Yes - Check if this hour is in the schedule?

	   				

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

	   				

	   				if (!in_array($this->now[1], $arHours) && $this->bits[1] != "*"){

	   					$this->debug("Cron not due in this hour, getting latest in last scheduled hour");

	   					//No - Get latest last hour

	   					sort($arHours);

	   					do{

	   						$hour = array_pop($arHours);

	   						//$this->debug("hour is $hour, now is ".$this->now[1]);

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

	   					

	   					$minute = $this->getExtremeMinute("END");

	   					

	   				} else if ($now < $this->getExtremeMinute("START") && $this->bits[1] != "*"){ //Not due to run this hour yet

	   					sort($arHours);

	   					do{

	   						$hour = array_pop($arHours);

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

	   					$minute = $this->getExtremeMinute("END");

	   				} else {

	   					//Yes, it is supposed to have run this hour already - Get last minute

	   					$hour = $this->now[1];

	   					if ($this->bits[0] != "*"){

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

		   					$this->debug($arMinutes);

		   					do{

		   						$minute = array_pop($arMinutes);		   						

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

		   					

		   					//If the first time in the hour that the cron is due to run is later than now, return latest last hour

		   					if($minute > $this->now[1] || $minute == ""){

		   						$this->debug("Valid minute not set");

		   						$minute = $this->getExtremeMinute("END"); //The minute will always be the last valid minute in an hour

		   						//Get the last hour.

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

		   							$hour = $this->now[1] - 1;

		   						} else {

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

			   						$this->debug("Array of hours:");

			   						$this->debug($arHours);

			   						sort($arHours);

		   							do{

		   								$hour = array_pop($arHours);

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

		   						}

		   					}

		   					

	   					} else {

	   						$minute = $this->now[0] -1; 

	   					}

	   				}  				

	   				

	   			}

	   			

	   		} 

		}

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

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



   }

     

   function getExtremeOfMonth($month, $year, $extreme){

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

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

			if ($this->bits[4] == "*"){//Is there a day range?

				//$this->debug("There were $daysInMonth days in $month, $year");

				if ($extreme == "END"){

					$day = $daysInMonth;

				} else {

					$day=1;

				}

			} else {//There's a day range.  Ignore the dateDay range and just get the list of possible weekday values.

				$days = $this->getWeekDays($this->bits[4],$month, $year);

				$this->debug($this->bits);

				$this->debug("Days array for ".$this->bits[4].", $month, $year:");

				$this->debug($days);

				if ($extreme == "END"){

					sort($days);

				} else {

					rsort($days);	

				}

				$day = array_pop($days);

			}

		} else {

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

			if ($extreme == "END"){

				sort($days);

			} else {

				rsort($days);	

			}

			

			do {

				$day = array_pop($days);

			} while($day > $daysInMonth);

		}	

		//$this->debug("$extreme day is $day");

		return $day;

   }

     

   function getDaysArray($month){

   		$this->debug("Getting days for $month");

   		$days = array();

   		

   		if ($this->bits[4] != "*"){   			

   			$days = $this->getWeekDays($this->bits[4], $month, $this->now[5]);

   			$this->debug("Weekdays:");

   			$this->debug($days);

   		} 

		if ($this->bits[2] != "*" && $this->bits[4] == "*") {

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

   		} 

   		if ($this->bits[2] == "*" && $this->bits[4] == "*"){

   			//Just return every day of the month

   			$daysinmonth = $this->daysinmonth($month, $this->now[5]);

   			$this->debug("Days in ".$month.", ".$this->now[5].": ".$daysinmonth);

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

   				$days[] = $i;

   			}

   		}

   		$this->debug($days);

   			

   		return $days;

   }

   

   function getExtremeHour($extreme){

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

			if ($extreme == "END"){

				$hour = 23;

			} else {

				$hour = 0;	

			}

		} else {

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

			if ($extreme == "END"){

				sort($hours);

			} else {

				rsort($hours);	

			}

			$hour = array_pop($hours);

		}

		//$this->debug("$extreme hour is $hour");

		return $hour;

   }

   

   function getExtremeMinute($extreme){

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

			if ($extreme == "END"){

				$minute = 59;

			} else {

				$minute = 0;	

			}

		} else {

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

			if ($extreme == "END"){

				sort($minutes);

			} else {

				rsort($minutes);	

			}

			$minute = array_pop($minutes);

		}

		//$this->debug("$extreme minute is $minute");

		return $minute;

   }



 }

?>