<?php
/**
 * By Greg MacLellan, Feb 13, 2005
 * based on work by heymeadows@yahoo.com
*/
/*

todo:

ideas:
- moon phases (http://www.zend.com/codex.php?id=830&single=1)

*/


/** A single holiday */
class Holiday {
	var $_name;
	var $_date;
	var $_type;
	
	/** Creates a new holiday object.
	 * @param  string  $name   The name of the holiday
	 * @param  date    $date   The date (unix timestamp, midnight) of the
	 *                         holiday
	 * @param  mixed   $type   An optional parameter for internal use, ie
	 *                         statutory holidays vs 'special' days
	 */
	function Holiday($name, $date, $type = 0) {
		$this->_name = $name;
		$this->_date = $date;
		$this->_type = $type;
	}
}

/** Creates a list of holidays
 * 
 * The default holiday list is for Canada
 *
 * @author Greg MacLellan (greg@gregmaclellan.com)
 */
class Holidays {
	var $holidays = array();
	
	/** Creates the Holidays object, and initalizes holidays for a given year
	 * @param  int  $year  The year in which to create holidays. If no year is given
	 *                     (value is null), then no holidays are initalized
	 */
	function Holidays($year = null) {
		if ($year) {
			$this->addHolidays($year);
		}
	}
	
	/** Gets a holiday for a given timestamp. The timestamp should be midnight of
	 * the requested day (ie, mktime(0,0,0, $month, $day, $year) )
	 * @param int  $date  The day to get holidays for
	 * @return  The Holiday object, or false if no holiday occurs that day
	 */
	function getHoliday($date) {
		return ($this->holidays[$date] ? $this->holidays[$date] : false); 
	}
	
	/** Adds a list of pre-defined holidays for the given year.
	 * This can be usful to add more than one years worth of holidays to the list
	 */
	function addHolidays($year) {
		$this->addHoliday(new Holiday("New Year's Day", mktime(0,0,0, 1, 1, $year), 1));			// January 1st
		$this->addHoliday(new Holiday("Groundhog Day", mktime(0,0,0, 2, 2, $year), 0));			// february 2nd
		$this->addHoliday(new Holiday("Valentine's Day", mktime(0,0,0, 2, 14, $year), 0));			// february 14th
		$this->addHoliday(new Holiday("St. Patrick's Day", mktime(0,0,0, 3, 17, $year), 0));		// march 17th
		$this->addHoliday(new Holiday("Good Friday", easter_date($year)-(86400*2), 1));			// friday before easter
		$this->addHoliday(new Holiday("Easter", easter_date($year), 1));					// Sunday after the first full moon which falls on or after the Spring Equinox
		$this->addHoliday(new Holiday("Easter Monday", easter_date($year)+86400, 1));			// monday after easter
		$this->addHoliday(new Holiday("Mother's Day", $this->ordinalDay(2, 'Sun', 5, $year), 0));		// 2nd sunday of may
		
		$this->addHoliday(new Holiday("Canada Day", mktime(0,0,0, 7, 1, $year), 1));				// july 1st
		if (date("w", mktime(0,0,0, 7, 1, $year)) == 0) {
			// if July 1st is a Sunday, then Canada Day holiday is july 2
			$this->addHoliday(new Holiday("Canada Day (Holiday)", mktime(0,0,0, 7, 2, $year), 1));	// july 2nd
		}
		
		$this->addHoliday(new Holiday("Father's Day", $this->ordinalDay(3, 'Sun', 6, $year), 0));		// 3rd sunday of june
		$this->addHoliday(new Holiday("Thanksgiving", $this->ordinalDay(2, 'Mon', 10, $year), 1)); 	// 2nd monday of october
		$this->addHoliday(new Holiday("Labour Day", $this->ordinalDay(1, 'Mon', 9, $year), 0));		// 1st monday of september
		$this->addHoliday(new Holiday("Rememberance Day", mktime(0,0,0, 11, 11, $year), 0));		// november 11th
		$this->addHoliday(new Holiday("Christmas", mktime(0,0,0, 12, 25, $year), 1));			// december 24th
		$this->addHoliday(new Holiday("Boxing Day", mktime(0,0,0, 12, 26, $year), 1));			// december 25th
	}
	
	/** Adds a single holiday object to the list of holidays
	 * @param Holiday  $holiday  The holiday object to add
	 */
	function addHoliday($holiday) {
		$this->holidays[$holiday->_date] = $holiday;
	}
	
	function ordinalDay($ord, $day, $month, $year) { 
		// ordinalDay returns date of the $ord $day of $month. 
		// For example ordinalDay(3, 'Sun', 5, 2001) returns the 
		// date of the 3rd Sunday of May (ie. Mother's Day). 
		// 
		// Note: $day must be the 3 char abbr. for the day, as 
		//       given by date("D"); 
		// 
		// By: heymeadows@yahoo.com
		// optimized a bit by greg maclellan 
		
		$firstOfMonth = mktime(0,0,0,$month,1,$year); 
		$lastOfMonth  = $firstOfMonth + date("t", $firstOfMonth) * 86400; 
		$dayOccurs = 0; 
		
		for ($i = $firstOfMonth; $i < $lastOfMonth ; $i += 86400) { 
			if (date("D", $i) == $day) { 
				$dayOccurs++; 
				if ($dayOccurs == $ord) { 
					$ordDay = $i;
				}  
	       	}
		}
		return $ordDay; 
	}
	
	
}

?>