Source for file Week.class.php

<?php
/**
 * @since 5/4/05
 * @package harmoni.primitives.chronology
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: Week.class.php,v 1.5 2007/09/04 20:25:25 adamfranco Exp $
 *
 * @link http://harmoni.sourceforge.net/
 * @author Adam Franco <adam AT adamfranco DOT com> <afranco AT middlebury DOT edu>
 */ 
 
require_once(dirname(__FILE__)."/Timespan.class.php");
 
/**
 * I am a Timespan that represents a Week.
 *
 * To create new Week instances, <b>use one of the static instance-creation
 * methods</b>, NOT 'new Week':
 *        - {@link current Week::current()}
 *        - {@link current Week::current()}
 *        - {@link epoch Week::epoch()}
 *        - {@link starting Week::starting($aDateAndTime)}
 *        - {@link startingDuration Week::startingDuration($aDateAndTime, $aDuration)}
 *        - {@link startingEnding Week::startingEnding($startDateAndTime, $endDateAndTime)}
 * 
 * @since 5/4/05
 * @package harmoni.primitives.chronology
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: Week.class.php,v 1.5 2007/09/04 20:25:25 adamfranco Exp $
 *
 * @link http://harmoni.sourceforge.net/
 * @author Adam Franco <adam AT adamfranco DOT com> <afranco AT middlebury DOT edu>
 */
class Week 
    extends Timespan
{
 
/*******************************************************
 * Class Methods
 *********************************************************/
 
 
    /**
     * Return the index of a string Day.
     * 
     * @param string $aNameString 
     * @return integer 
     * @access public
     * @since 5/4/05
     */
    function indexOfDay ( $aNameString ) {
        foreach (ChronologyConstants::DayNames() as $i => $name) {
            if (preg_match("/$aNameString.*/i", $name))
                return $i;
        }
        
        $errorString = $aNameString ." is not a recognized day name.";
        if (function_exists('throwError'))
            throwError(new Error($errorString));
        else
            die ($errorString);
    }
    
    /**
     * Return the name of the day at index.
     * 
     * @param integer $anInteger 
     * @return string 
     * @access public
     * @since 5/4/05
     */
    function nameOfDay ( $anInteger ) {
        $names = ChronologyConstants::DayNames();
        if ($names[$anInteger])
            return $names[$anInteger];
        
        $errorString = $anInteger ." is not a valid day index.";
        if (function_exists('throwError'))
            throwError(new Error($errorString));
        else
            die ($errorString);
    }
    
    /**
     * Answer the day at the start of the week
     * 
     * @return string 
     * @access public
     * @since 5/20/05
     */
    function startDay () {
        $dayNames = ChronologyConstants::DayNames();
        return $dayNames[1];
    }
    
/*******************************************************
 * Class Methods - Instance Creation
 *
 * All static instance creation methods have an optional
 * $class parameter which is used to get around the limitations
 * of not being    able to find the class of the object that
 * recieved the initial method call rather than the one in
 * which it is implemented. These parameters SHOULD NOT BE
 * USED OUTSIDE OF THIS PACKAGE.
 *********************************************************/
 
 
     /**
     * Answer a new object that represents now.
     * 
     * @param optional string $class DO NOT USE OUTSIDE OF PACKAGE.
     *         This parameter is used to get around the limitations of not being
     *         able to find the class of the object that recieved the initial
     *         method call.
     * @return object Week 
     * @access public
     * @since 5/5/05
     * @static
     */
    function current ( $class = 'Week' ) {
        $obj = parent::current($class);
        return $obj;
    }
    
    /**
     * Answer a Month starting on the Squeak epoch: 1 January 1901
     * 
     * @param optional string $class DO NOT USE OUTSIDE OF PACKAGE.
     *         This parameter is used to get around the limitations of not being
     *         able to find the class of the object that recieved the initial
     *         method call.
     * @return object Week 
     * @access public
     * @since 5/5/05
     * @static
     */
    function epoch ( $class = 'Week' ) {
        $obj = parent::epoch($class);
        return $obj;
    }
    
    /**
     * Create a new object starting now, with zero duration
     * 
     * @param object DateAndTime $aDateAndTime 
     * @param optional string $class DO NOT USE OUTSIDE OF PACKAGE.
     *         This parameter is used to get around the limitations of not being
     *         able to find the class of the object that recieved the initial
     *         method call.
     * @return object Week 
     * @access public
     * @since 5/5/05
     * @static
     */
    function starting ( $aDateAndTime, $class = 'Week' ) {
        $obj = parent::starting($aDateAndTime, $class);
        return $obj;
    }
    
    /**
     * Create a new object with given start and end DateAndTimes
     * 
     * @param object DateAndTime $startDateAndTime 
     * @param object DateAndTime $endDateAndTime 
     * @param optional string $class DO NOT USE OUTSIDE OF PACKAGE.
     *         This parameter is used to get around the limitations of not being
     *         able to find the class of the object that recieved the initial
     *         method call.
     * @return object Week 
     * @access public
     * @since 5/11/05
     */
    function startingEnding ( $startDateAndTime, $endDateAndTime, 
        $class = 'Week' ) 
    {
        $obj = parent::startingEnding ( $startDateAndTime, $endDateAndTime, $class);
        return $obj;
    }
    
        
    /**
     * Create a new object starting now, with a given duration.
     * Override - as each Week has a defined duration
     * 
     * @param object DateAndTime $aDateAndTime 
     * @param object Duration $aDuration 
     * @param optional string $class DO NOT USE OUTSIDE OF PACKAGE.
     *         This parameter is used to get around the limitations of not being
     *         able to find the class of the object that recieved the initial
     *         method call.
     * @return object Week 
     * @access public
     * @since 5/5/05
     * @static
     */
    function startingDuration ( $aDateAndTime, $aDuration, $class = 'Week' ) {
        
        // Validate our passed class name.
        if (!(strtolower($class) == strtolower('Week')
            || is_subclass_of(new $class, 'Week')))
        {
            die("Class, '$class', is not a subclass of 'Week'.");
        }
        
        $asDateAndTime =$aDateAndTime->asDateAndTime();
        $midnight =$asDateAndTime->atMidnight();
        $dayNames = ChronologyConstants::DayNames();
        $temp = $midnight->dayOfWeek() + 7 - array_search(Week::startDay(), $dayNames);
        $delta =  abs($temp - (intval($temp/7) * 7));
        
        $adjusted =$midnight->minus(Duration::withDays($delta));
        
        $obj = parent::startingDuration($adjusted, Duration::withWeeks(1), $class);
        
        return $obj;
    }
 
    
/*******************************************************
 * Instance Methods - Converting
 *********************************************************/
 
     
     /**
      * Answer the receiver as a Week
      * 
      * @return object Week 
      * @access public
      * @since 5/23/05
      */
     function asWeek () {
         return $this;
     }
}
 
?>