<?php
// Modification log
// (date)       (author)    (activity/purpose)
//
// Todo
// (date)       (author)    (activity/purpose)
//

assert_options(ASSERT_WARNING, 0);
require_once 'classes/XML/class.XmlNode.php';

/**
 * Enumeration of months
 * @access public
 */
define('M_JANUARY', '1');
define('M_FEBRUARY', '2');
define('M_MARCH', '3');
define('M_APRIL', '4');
define('M_MAY', '5');
define('M_JUNE', '6');
define('M_JULY', '7');
define('M_AUGUST', '8');
define('M_SEPTEMBER', '9');
define('M_OCTOBER', '10');
define('M_NOVEMBER', '11');
define('M_DECEMBER', '12');


/**
 * Creates the basic date values etc for a specified month
 *
 * This class creates a basic representation of a month, providing the dates of the days
 * each week, and the weeknumbers of each week.
 *
 * @author Tommy Gildseth <tommy@akili.no>;
 * @author Akili AS <post@akili.no>;
 * @copyright Akili AS, Sept 2003
 * @access public
 * @package Calendar
 */
class Month
    {
    //{{{ Class variables
    /**
     * @var integer $_month The number of the month from 1 - 12, of the month the
     *                      object refers to.
     * @access private
     */
    var $_month;

    /**
     * @var integer $_year The year the month object refers to
     * @access private
     */
    var $_year;

    /**
     * @var array   $_week A 2d array containing the weeks of the month
     * @access private
     */
    var $_week = array();

    /**
     * @var array   $_weekNum A 2d array containing the weeks of the month
     * @access private
     */
    var $_weekNum = array();

    //}}}

    //{{{Constructor
    /**
     * Constructor for the Month class.
     *
     * @param   integer $month  The month which should be displayed.
     * @param   integer $year   The year which contains the month
     * @access public
     */
    function Month( $month, $year )
        {
        $this->_month = $month;
        $this->_year = $year;
        $this->_createMonth($month, $year);
        }//}}}end Constructor

    //{{{ _createMonth
    /**
     * Does the job of calculating the days of the month
     *
     * Creates a 2d array to keep each week, with the days dates as the second
     * dimension, and an array containing the week numbers of the weeks in $month
     *
     * @param   integer $month  The month which should be displayed.
     * @param   integer $year   The year which should be displayed
     * @access private
     */
    function _createMonth( $month, $year )
        {
        //Get timestamp for first and last day of the month
        $firstDayTS = mktime ( 0, 0, 0, $month, 1, $year);
        $lastDayTS = mktime ( 0, 0, 0, $month+1, 0, $year);

        //Get weeknumber of first week of the month
        $week = date('W', $firstDayTS);

        //Get weekday number of first and last day of the month(ie Mon=1, Tues=2 etc etc.)
        //PHP actually thinks sunday is day number 0 and not 7 so we need to rectify
        //this "mistake".
        $firstDay = date('w', $firstDayTS);
        $firstDay = ($firstDay == '0')?7:$firstDay;
        $lastDay = date('w', $lastDayTS);
        $lastDay = ($lastDay == '0')?7:$lastDay;

        //Find how many days from the first week belong to the previous month.
        $firstDay = ($firstDay-1) * (-1);
        //mktime ( int hour, int minute, int second, int month, int day, int year [, int is_dst])
        $daysInMonth = date('t', $firstDayTS);
        while($firstDay < $daysInMonth)
            {
            if ($week >= 52)
                $week = $week = date('W', mktime ( 0, 0, 0, $month, $firstDay+7, $year));
            $this->_weekNum[] = $week++;
            $this->_createWeek($firstDay,
                               $month,
                               $year);
            $firstDay += 7;
            }
        }//}}}end _createMonth

    //{{{ _createWeek
    /**
     * Create an array containing the dates of the days in the week starting at $from
     *
     * @param   integer $from   The day of the month which the weeks first day is on.
     * @param   integer $month  The month containing this week
     * @param   integer $year   The year containing this week
     * @access private
     */
    function _createWeek( $from, $month, $year )
        {
        $daysInMonth = date('t', mktime ( 0, 0, 0, $month, 1, $year));
        $daysInPrevMonth = date('t', mktime ( 0, 0, 0, $month, 0, $year));

        $dayNumbers = array();
        for ($i = 1; $i <= 7; ++$i)
            {
            if (($from +$i) < 1) //If previous month
                {
                //$from is a negative number, therefor + and not -
                $day = $daysInPrevMonth + $from + $i;
                }
            else if (($from +$i) > $daysInMonth) //If next month
                {
                $day = $from + $i - $daysInMonth;
                }
            else
                {
                $day = $from+$i;
                }
            $dayNumbers[] = $day;
            }
        $this->_week[] = $dayNumbers;
        }//}}}end _createWeek

    function getMonth( )
        {
        return $this->_month;
        }

    function getYear( )
        {
        return $this->_year;
        }

    function getWeeks( )
        {
        return $this->_week;
        }

    function getWeekNum( )
        {
        return $this->_weekNum;
        }

    function getRootNode( )
        {
        $root = new XmlNode('month');
        $root->addChild('.', new XmlNode('nr', null, $this->_month));
        $root->addChild('.', new XmlNode('year', null, $this->_year));

        $weeks = count($this->_week);
        for ($i = 0; $i < $weeks; ++$i)
            {
            $week = new XmlNode('week');
            $week->addChild('.', new XmlNode('nr', null, $this->_weekNum[$i]));
            foreach($this->_week[$i] as $dayNr)
                {
                $day = new XmlNode('day');
                $day->addChild('.', new XmlNode('nr', null, $dayNr));
                $day->addChild('.', new XmlNode('ts',
                                                null,
                                                mktime(0,0,0,
                                                       $this->_month,
                                                       $dayNr,
                                                       $this->_year)));
                $week->addChild('.', $day);
                unset($day);
                }

            $root->addChild('.', $week);
            unset ($week);
            }
        return $root;
        }

    function getXmlMonth( )
        {
        $root = $this->getRootNode();
        return $root->getXmlString();
        }
    }
?>