<?php
/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2015 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
 * Website: http://www.espocrm.com
 *
 * EspoCRM is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * EspoCRM 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
 ************************************************************************/

namespace Espo\Modules\Crm\Business\Event;

class Ics
{
    private $_d_end;

    private $_d_start;

    private $_s_address;

    private $_s_description;

    private $_s_html;
    
    private $_s_who;
    
    private $_s_email;

    private $_s_uri;
    
    private $_s_uid;

    private $_s_summary;

    private $_s_output;

    private $_s_prodid;
    
    public function __construct($prodid, array $attributes = array())
    {
        if (!is_string($prodid) || $prodid === '') {
            throw new \Exception('PRODID is required');
        }

        $this->_s_prodid = $prodid;

        foreach ($attributes as $key => $value) {
            $this->$key = $value;
        }
    }
    
    public function __set($name, $value)
    {
        switch ($name) {
            case 'startDate':
                $this->_d_start = $value;
                break;

            case 'endDate':
                $this->_d_end = $value;
                break;

            case 'address':
                $this->_s_address = $value;
                break;

            case 'summary':
                $this->_s_summary = $value;
                break;
                
            case 'who':
                $this->_s_who = $value;
                break;
                
            case 'email':
                $this->_s_email = $value;
                break;

            case 'uri':
                $this->_s_uri = $value;
                break;
                
            case 'uid':
                $this->_s_uid = $value;
                break;

            case 'description':
                $this->_s_description = $value;
                break;

            case 'html':
                $this->_s_html = $value;
                break;
        }

        return $this;
    }
    
    public function __get($name) {
        switch ($name)
        {
            case 'startDate':
                return $this->_d_start;
                break;

            case 'endDate':
                return $this->_d_end;
                break;

            case 'address':
                return $this->_s_address;
                break;

            case 'summary':
                return $this->_s_summary;
                break;

            case 'uri':
                return $this->_s_uri;
                break;
                
            case 'who':
                return $this->_s_who;
                break;
                
            case 'email':
                return $this->_s_email;
                break;
                
            case 'uid':
                return $this->_s_uid;
                break;

            case 'description':
                return $this->_s_description;
                break;

            case 'html':
                return $this->_s_html;
                break;
        }
    }
    
    public function get()
    {
        ($this->_s_output) ? $this->_s_output : $this->_generate();

        return $this->_s_output;
    }
    
    private function _generate()
    {
        $this->_s_output = "BEGIN:VCALENDAR\n".
               "VERSION:2.0\n".
                 "PRODID:-".$this->_s_prodid."\n".
                 "METHOD:REQUEST\n".
                 "BEGIN:VEVENT\n".
                 "DTSTART:".$this->_dateToCal($this->startDate)."\n".
                 "DTEND:".$this->_dateToCal($this->endDate)."\n".
                 "SUMMARY:New ".$this->_escapeString($this->summary)."\n".
                 "LOCATION:".$this->_escapeString($this->address)."\n".
                 "ORGANIZER;CN=".$this->_escapeString($this->who).":MAILTO:" . $this->_escapeString($this->email)."\n".
                 "DESCRIPTION:".$this->_escapeString($this->description)."\n".
                 "X-ALT-DESC;FMTTYPE=text/html:".$this->_escapeString($this->html)."\n".
                 "URL;VALUE=URI:".$this->_escapeString($this->uri)."\n".
                 "UID:".$this->uid."\n".
                 "SEQUENCE:0\n".
                 "DTSTAMP:".$this->_dateToCal(time())."\n".
                 "END:VEVENT\n".
                 "END:VCALENDAR\n";
    }
    
    private function _dateToCal($timestamp)
    {
        return date('Ymd\THis\Z', ($timestamp) ? $timestamp : time());
    }

    private function _escapeString($string)
    {
        return preg_replace('/([\,;])/','\\\$1', ($string) ? $string : '');
    }    
}