<?php

require_once realpath(__DIR__ . '/../../libcalendaring/lib/libcalendaring_recurrence.php');

/**
 * Recurrence computation class for the Calendar plugin
 *
 * Uitility class to compute instances of recurring events.
 *
 * @author Thomas Bruederli <bruederli@kolabsys.com>
 *
 * Copyright (C) 2012-2014, 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 calendar_recurrence extends libcalendaring_recurrence
{
    private $event;
    private $duration;

    /**
     * Default constructor
     *
     * @param calendar $cal   The calendar plugin instance
     * @param array    $event The event object to operate on
     */
    function __construct($cal, $event)
    {
        parent::__construct($cal->lib);

        $this->event = $event;

        if (is_object($event['start']) && is_object($event['end'])) {
            $this->duration = $event['start']->diff($event['end']);
        }

        $event['start']->_dateonly = !empty($event['allday']);

        $this->init($event['recurrence'], $event['start']);
    }

    /**
     * Alias of libcalendaring_recurrence::next()
     *
     * @return mixed DateTime object or False if recurrence ended
     */
    public function next_start()
    {
        return $this->next();
    }

    /**
     * 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()) {
            $next = $this->event;
            $next['start'] = $next_start;

            if ($this->duration) {
                $next['end'] = clone $next_start;
                $next['end']->add($this->duration);
            }

            $next['recurrence_date'] = clone $next_start;
            $next['_instance'] = libcalendaring::recurrence_instance_identifier($next, $this->event['allday']);

            unset($next['_formatobj']);

            return $next;
        }

        return false;
    }
}