<?php // BUILD: Remove line

/**
 * A collection of functions to query the events in a calendar.
 *
 * @package SG_iCalReader
 * @author Morten Fangel (C) 2008
 * @license http://creativecommons.org/licenses/by-sa/2.5/dk/deed.en_GB CC-BY-SA-DK
 */
class SG_iCal_Query {
    /**
     * Returns all events from the calendar between two timestamps
     *
     * Note that the events returned needs only slightly overlap.
     *
     * @param SG_iCalReader|array $ical The calendar to query
     * @param int $start
     * @param int $end
     * @return SG_iCal_VEvent[]
     */
    public static function Between( $ical, $start, $end ) {
        if( $ical instanceof SG_iCalReader ) {
            $ical = $ical->getEvents();
        }
        if( !is_array($ical) ) {
            throw new Exception('SG_iCal_Query::Between called with invalid input!');
        }

        $rtn = array();
        foreach( $ical AS $e ) {
            if( ($start <= $e->getStart() && $e->getStart() < $end)
             || ($start < $e->getRangeEnd() && $e->getRangeEnd() <= $end) ) {
                $rtn[] = $e;
            }
        }
        return $rtn;
    }

    /**
     * Returns all events from the calendar after a given timestamp
     *
     * @param SG_iCalReader|array $ical The calendar to query
     * @param int $start
     * @return SG_iCal_VEvent[]
     */
    public static function After( $ical, $start ) {
        if( $ical instanceof SG_iCalReader ) {
            $ical = $ical->getEvents();
        }
        if( !is_array($ical) ) {
            throw new Exception('SG_iCal_Query::After called with invalid input!');
        }

        $rtn = array();
        foreach( $ical AS $e ) {
            if($e->getStart() >= $start || $e->getRangeEnd() >= $start) {
                $rtn[] = $e;
            }
        }
        return $rtn;
    }

    /**
     * Sorts the events from the calendar after the specified column.
     * Column can be all valid entires that getProperty can return.
     * So stuff like uid, start, end, summary etc.
     * @param SG_iCalReader|array $ical The calendar to query
     * @param string $column
     * @return SG_iCal_VEvent[]
     */
    public static function Sort( $ical, $column ) {
        if( $ical instanceof SG_iCalReader ) {
            $ical = $ical->getEvents();
        }
        if( !is_array($ical) ) {
            throw new Exception('SG_iCal_Query::Sort called with invalid input!');
        }

        $cmp = create_function('$a, $b', 'return strcmp($a->getProperty("' . $column . '"), $b->getProperty("' . $column . '"));');
        usort($ical, $cmp);
        return $ical;
    }
}