roundcubemail-plugins-kolab/plugins/libkolab/lib/kolab_date_recurrence.php

113 lines
3.7 KiB
PHP

<?php
/**
* Recurrence computation class for xcal-based Kolab format objects
*
* Utility class to compute instances of recurring events.
* It requires the libcalendaring PHP module to be installed and loaded.
*
* @version @package_version@
* @author Thomas Bruederli <bruederli@kolabsys.com>
*
* Copyright (C) 2012, Kolab Systems AG <contact@kolabsys.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
class kolab_date_recurrence
{
private /* EventCal */ $engine;
private /* kolab_format_xcal */ $object;
private /* DateTime */ $start;
private /* DateTime */ $next;
private /* DateInterval */ $duration;
/**
* Default constructor
*
* @param array The Kolab object to operate on
*/
function __construct($object)
{
$data = $object->to_array();
$this->object = $object;
$this->engine = $object->to_libcal();
$this->start = $this->next = $data['start'];
if (is_object($data['start']) && is_object($data['end']))
$this->duration = $data['start']->diff($data['end']);
else
$this->duration = new DateInterval('PT' . ($data['end'] - $data['start']) . 'S');
}
/**
* Get date/time of the next occurence of this event
*
* @param boolean Return a Unix timestamp instead of a DateTime object
* @return mixed DateTime object/unix timestamp or False if recurrence ended
*/
public function next_start($timestamp = false)
{
$time = false;
if ($this->engine && $this->next) {
$cstart = kolab_format::get_datetime($this->next);
if ($next = kolab_format::php_datetime(new cDateTime($this->engine->getNextOccurence($cstart)))) {
$time = $timestamp ? $next->format('U') : $next;
$this->next = $next;
}
}
return $time;
}
/**
* Get the next recurring instance of this event
*
* @return mixed Array with event properties or False if recurrence ended
*/
public function next_instance()
{
if ($next_start = $this->next_start()) {
$next_end = clone $next_start;
$next_end->add($this->duration);
$next = $this->object->to_array();
$next['recurrence_id'] = $next_start->format('Y-m-d');
$next['start'] = $next_start;
$next['end'] = $next_end;
unset($next['_formatobj']);
return $next;
}
return false;
}
/**
* Get the end date of the occurence of this recurrence cycle
*
* @param string Date limit (where infinite recurrences should abort)
* @return mixed Timestamp with end date of the last event or False if recurrence exceeds limit
*/
public function end($limit = 'now +1 year')
{
$limit_dt = new DateTime($limit);
if ($this->engine && ($cend = $this->engine->getLastOccurrence()) && ($end_dt = kolab_format::php_datetime(new cDateTime($cend))) && $end_dt < $limit_dt) {
return $end_dt->format('U');
}
return false;
}
}