nextcloud/3dparty/Sabre/CalDAV/ICalendarUtil.php

156 lines
5.4 KiB
PHP

<?php
/**
* This class contains several utilities related to the ICalendar (rfc2445) format
*
* This class is now deprecated, and won't be further maintained. Please use
* the Sabre_VObject package for your ics parsing needs.
*
* @package Sabre
* @subpackage CalDAV
* @copyright Copyright (C) 2007-2011 Rooftop Solutions. All rights reserved.
* @author Evert Pot (http://www.rooftopsolutions.nl/)
* @license http://code.google.com/p/sabredav/wiki/License Modified BSD License
* @deprecated Use Sabre_VObject instead.
*/
class Sabre_CalDAV_ICalendarUtil {
/**
* Validates an ICalendar object
*
* This method makes sure this ICalendar object is properly formatted.
* If we can't parse it, we'll throw exceptions.
*
* @param string $icalData
* @param array $allowedComponents
* @return bool
*/
static function validateICalendarObject($icalData, array $allowedComponents) {
$xcal = simplexml_load_string(self::toXCal($icalData));
if (!$xcal) throw new Sabre_CalDAV_Exception_InvalidICalendarObject('Invalid calendarobject format');
$xcal->registerXPathNameSpace('cal','urn:ietf:params:xml:ns:xcal');
// Check if there's only 1 component
$components = array('vevent','vtodo','vjournal','vfreebusy');
$componentsFound = array();
foreach($components as $component) {
$test = $xcal->xpath('/cal:iCalendar/cal:vcalendar/cal:' . $component);
if (is_array($test)) $componentsFound = array_merge($componentsFound, $test);
}
if (count($componentsFound)<1) {
throw new Sabre_CalDAV_Exception_InvalidICalendarObject('One VEVENT, VTODO, VJOURNAL or VFREEBUSY must be specified. 0 found.');
}
$component = $componentsFound[0];
// Check if the component is allowed
$name = $component->getName();
if (!in_array(strtoupper($name),$allowedComponents)) {
throw new Sabre_CalDAV_Exception_InvalidICalendarObject(strtoupper($name) . ' is not allowed in this calendar.');
}
if (count($xcal->xpath('/cal:iCalendar/cal:vcalendar/cal:method'))>0) {
throw new Sabre_CalDAV_Exception_InvalidICalendarObject('The METHOD property is not allowed in calendar objects');
}
return true;
}
/**
* Converts ICalendar data to XML.
*
* Properties are converted to lowercase xml elements. Parameters are;
* converted to attributes. BEGIN:VEVENT is converted to <vevent> and
* END:VEVENT </vevent> as well as other components.
*
* It's a very loose parser. If any line does not conform to the spec, it
* will simply be ignored. It will try to detect if \r\n or \n line endings
* are used.
*
* @todo Currently quoted attributes are not parsed correctly.
* @see http://tools.ietf.org/html/draft-royer-calsch-xcal-03
* @param string $icalData
* @return string.
*/
static function toXCAL($icalData) {
// Detecting line endings
$lb="\r\n";
if (strpos($icalData,"\r\n")!==false) $lb = "\r\n";
elseif (strpos($icalData,"\n")!==false) $lb = "\n";
// Splitting up items per line
$lines = explode($lb,$icalData);
// Properties can be folded over 2 lines. In this case the second
// line will be preceeded by a space or tab.
$lines2 = array();
foreach($lines as $line) {
if (!$line) continue;
if ($line[0]===" " || $line[0]==="\t") {
$lines2[count($lines2)-1].=substr($line,1);
continue;
}
$lines2[]=$line;
}
$xml = '<?xml version="1.0"?>' . "\n";
$xml.= "<iCalendar xmlns=\"urn:ietf:params:xml:ns:xcal\">\n";
$spaces = 2;
foreach($lines2 as $line) {
$matches = array();
// This matches PROPERTYNAME;ATTRIBUTES:VALUE
if (!preg_match('/^([^:^;]*)(?:;([^:]*))?:(.*)$/',$line,$matches))
continue;
$propertyName = strtolower($matches[1]);
$attributes = $matches[2];
$value = $matches[3];
// If the line was in the format BEGIN:COMPONENT or END:COMPONENT, we need to special case it.
if ($propertyName === 'begin') {
$xml.=str_repeat(" ",$spaces);
$xml.='<' . strtolower($value) . ">\n";
$spaces+=2;
continue;
} elseif ($propertyName === 'end') {
$spaces-=2;
$xml.=str_repeat(" ",$spaces);
$xml.='</' . strtolower($value) . ">\n";
continue;
}
$xml.=str_repeat(" ",$spaces);
$xml.='<' . $propertyName;
if ($attributes) {
// There can be multiple attributes
$attributes = explode(';',$attributes);
foreach($attributes as $att) {
list($attName,$attValue) = explode('=',$att,2);
$attName = strtolower($attName);
if ($attName === 'language') $attName='xml:lang';
$xml.=' ' . $attName . '="' . htmlspecialchars($attValue) . '"';
}
}
$xml.='>'. htmlspecialchars(trim($value)) . '</' . $propertyName . ">\n";
}
$xml.="</iCalendar>";
return $xml;
}
}