<?php

/*
 +--------------------------------------------------------------------+
 | CiviCRM version 3.0                                                |
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC (c) 2004-2009                                |
 +--------------------------------------------------------------------+
 | This file is a part of CiviCRM.                                    |
 |                                                                    |
 | CiviCRM is free software; you can copy, modify, and distribute it  |
 | under the terms of the GNU Affero General Public License           |
 | Version 3, 19 November 2007.                                       |
 |                                                                    |
 | CiviCRM 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, contact CiviCRM LLC       |
 | at info[AT]civicrm[DOT]org. If you have questions about the        |
 | GNU Affero General Public License or the licensing of CiviCRM,     |
 | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
 +--------------------------------------------------------------------+
*/

/**
 *
 * @package CRM
 * @copyright CiviCRM LLC (c) 2004-2009
 * $Id$
 *
 */

/**
 * @file
 * API for event export in iCalendar format 
 * as outlined in Internet Calendaring and 
 * Scheduling Core Object Specification
 * 
 */
class CRM_Utils_ICalendar 
{

    /**
     * Escape text elements for safe ICalendar use
     *
     * @param $text Text to escape
     *
     * @return  Escaped text
     *
     */
    static function formatText( $text ) 
    {
        $text = strip_tags($text);
        $text = str_replace("\"", "DQUOTE", $text);
        $text = str_replace("\\", "\\\\", $text);
        $text = str_replace(",", "\,", $text);
        $text = str_replace(":", "\":\"", $text);
        $text = str_replace(";", "\;", $text);
        $text = str_replace("\n", "\n ", $text);
        return $text;
    }

    /**
     * Escape date elements for safe ICalendar use
     *
     * @param $date Date to escape
     *
     * @return  Escaped date
     *
     */
    static function formatDate( $date, $gdata = false )
    {

        if ( $gdata ) {
            return date( "Y-m-d\TH:i:s.000",
                           strtotime( $date ) );
        } else {
            return date( "Ymd\THis",
                           strtotime( $date ) );
        }
    }

    /**
     *
     * Send the ICalendar to the browser with the specified content type
     * - 'text/calendar' : used for downloaded ics file
     * - 'text/plain'    : used for iCal formatted feed
     * - 'text/xml'      : used for gData or rss formatted feeds
     *
     * @access public
     * 
     * @param string $content_type 
     * 
     * @param string $filename The file name (for downloads)
     *
     * @param string $disposition How the file should be sent ('attachment' for downloads)
     * 
     * @param string $charset The character set to use, defaults to
     * 'us-ascii'.
     *
     * @param string $calendar The calendar data to be published.
     * 
     * @return void
     * 
     */ 
    function send( $calendar, $content_type = 'text/calendar', $charset = 'us-ascii', $fileName = null, $disposition = null )
    {
        require_once 'CRM/Core/Config.php';
        $config =& CRM_Core_Config::singleton();
        $lang = $config->lcMessages;
        header( "Content-Language: $lang" );
        // header( "Content-Type: $content_type; charset=$charset; profile=\"ICalendar\"" );
        header( "Content-Type: $content_type" );
        
        if ( $content_type == 'text/calendar') {
            header('Content-Length: ' . strlen($calendar));
            header("Content-Disposition: $disposition; filename=\"$fileName\"");
        }
        
        echo $calendar;
    }
}


