moodle/lib/bennu/iCalendar_components.php

410 lines
14 KiB
PHP

<?php
/**
* BENNU - PHP iCalendar library
* (c) 2005-2006 Ioannis Papaioannou (pj@moodle.org). All rights reserved.
*
* Released under the LGPL.
*
* See http://bennu.sourceforge.net/ for more information and downloads.
*
* @author Ioannis Papaioannou
* @version $Id$
* @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
*/
class iCalendar_component {
var $name = NULL;
var $properties = NULL;
var $components = NULL;
var $valid_properties = NULL;
var $valid_components = NULL;
function iCalendar_component() {
$this->construct();
}
function construct() {
// Initialize the components array
if(empty($this->components)) {
$this->components = array();
foreach($this->valid_components as $name) {
$this->components[$name] = array();
}
}
}
function get_name() {
return $this->name;
}
function add_property($name, $value = NULL, $parameters = NULL) {
// Uppercase first of all
$name = strtoupper($name);
// Are we trying to add a valid property?
$xname = false;
if(!isset($this->valid_properties[$name])) {
// If not, is it an x-name as per RFC 2445?
if(!rfc2445_is_xname($name)) {
return false;
}
// Since this is an xname, all components are supposed to allow this property
$xname = true;
}
// Create a property object of the correct class
if($xname) {
$property = new iCalendar_property_x;
$property->set_name($name);
}
else {
$classname = 'iCalendar_property_'.strtolower(str_replace('-', '_', $name));
$property = new $classname;
}
// If $value is NULL, then this property must define a default value.
if($value === NULL) {
$value = $property->default_value();
if($value === NULL) {
return false;
}
}
// Set this property's parent component to ourselves, because some
// properties behave differently according to what component they apply to.
$property->set_parent_component($this->name);
// Set parameters before value; this helps with some properties which
// accept a VALUE parameter, and thus change their default value type.
// The parameters must be valid according to property specifications
if(!empty($parameters)) {
foreach($parameters as $paramname => $paramvalue) {
if(!$property->set_parameter($paramname, $paramvalue)) {
return false;
}
}
// Some parameters interact among themselves (e.g. ENCODING and VALUE)
// so make sure that after the dust settles, these invariants hold true
if(!$property->invariant_holds()) {
return false;
}
}
// $value MUST be valid according to the property data type
if(!$property->set_value($value)) {
return false;
}
// If this property is restricted to only once, blindly overwrite value
if(!$xname && $this->valid_properties[$name] & RFC2445_ONCE) {
$this->properties[$name] = array($property);
}
// Otherwise add it to the instance array for this property
else {
$this->properties[$name][] = $property;
}
// Finally: after all these, does the component invariant hold?
if(!$this->invariant_holds()) {
// If not, completely undo the property addition
array_pop($this->properties[$name]);
if(empty($this->properties[$name])) {
unset($this->properties[$name]);
}
return false;
}
return true;
}
function add_component($component) {
// With the detailed interface, you can add only components with this function
if(!is_object($component) || !is_subclass_of($component, 'iCalendar_component')) {
return false;
}
$name = $component->get_name();
// Only valid components as specified by this component are allowed
if(!in_array($name, $this->valid_components)) {
return false;
}
// Add it
$this->components[$name][] = $component;
return true;
}
function get_property_list($name) {
}
function invariant_holds() {
return true;
}
function is_valid() {
// If we have any child components, check that they are all valid
if(!empty($this->components)) {
foreach($this->components as $component => $instances) {
foreach($instances as $number => $instance) {
if(!$instance->is_valid()) {
return false;
}
}
}
}
// Finally, check the valid property list for any mandatory properties
// that have not been set and do not have a default value
foreach($this->valid_properties as $property => $propdata) {
if(($propdata & RFC2445_REQUIRED) && empty($this->properties[$property])) {
$classname = 'iCalendar_property_'.strtolower(str_replace('-', '_', $property));
$object = new $classname;
if($object->default_value() === NULL) {
return false;
}
unset($object);
}
}
return true;
}
function serialize() {
// Check for validity of the object
if(!$this->is_valid()) {
return false;
}
// Maybe the object is valid, but there are some required properties that
// have not been given explicit values. In that case, set them to defaults.
foreach($this->valid_properties as $property => $propdata) {
if(($propdata & RFC2445_REQUIRED) && empty($this->properties[$property])) {
$this->add_property($property);
}
}
// Start tag
$string = rfc2445_fold('BEGIN:'.$this->name) . RFC2445_CRLF;
// List of properties
if(!empty($this->properties)) {
foreach($this->properties as $name => $properties) {
foreach($properties as $property) {
$string .= $property->serialize();
}
}
}
// List of components
if(!empty($this->components)) {
foreach($this->components as $name => $components) {
foreach($components as $component) {
$string .= $component->serialize();
}
}
}
// End tag
$string .= rfc2445_fold('END:'.$this->name) . RFC2445_CRLF;
return $string;
}
}
class iCalendar extends iCalendar_component {
var $name = 'VCALENDAR';
function construct() {
$this->valid_properties = array(
'CALSCALE' => RFC2445_OPTIONAL | RFC2445_ONCE,
'METHOD' => RFC2445_OPTIONAL | RFC2445_ONCE,
'PRODID' => RFC2445_REQUIRED | RFC2445_ONCE,
'VERSION' => RFC2445_REQUIRED | RFC2445_ONCE,
RFC2445_XNAME => RFC2445_OPTIONAL
);
$this->valid_components = array(
'VEVENT'
// TODO: add support for the other component types
//, 'VTODO', 'VJOURNAL', 'VFREEBUSY', 'VTIMEZONE', 'VALARM'
);
parent::construct();
}
}
class iCalendar_event extends iCalendar_component {
var $name = 'VEVENT';
var $properties;
function construct() {
$this->valid_components = array('VALARM');
$this->valid_properties = array(
'CLASS' => RFC2445_OPTIONAL | RFC2445_ONCE,
'CREATED' => RFC2445_OPTIONAL | RFC2445_ONCE,
'DESCRIPTION' => RFC2445_OPTIONAL | RFC2445_ONCE,
// Standard ambiguous here: in 4.6.1 it says that DTSTAMP in optional,
// while in 4.8.7.2 it says it's REQUIRED. Go with REQUIRED.
'DTSTAMP' => RFC2445_REQUIRED | RFC2445_ONCE,
// Standard ambiguous here: in 4.6.1 it says that DTSTART in optional,
// while in 4.8.2.4 it says it's REQUIRED. Go with REQUIRED.
'DTSTART' => RFC2445_REQUIRED | RFC2445_ONCE,
'GEO' => RFC2445_OPTIONAL | RFC2445_ONCE,
'LAST-MODIFIED' => RFC2445_OPTIONAL | RFC2445_ONCE,
'LOCATION' => RFC2445_OPTIONAL | RFC2445_ONCE,
'ORGANIZER' => RFC2445_OPTIONAL | RFC2445_ONCE,
'PRIORITY' => RFC2445_OPTIONAL | RFC2445_ONCE,
'SEQUENCE' => RFC2445_OPTIONAL | RFC2445_ONCE,
'STATUS' => RFC2445_OPTIONAL | RFC2445_ONCE,
'SUMMARY' => RFC2445_OPTIONAL | RFC2445_ONCE,
'TRANSP' => RFC2445_OPTIONAL | RFC2445_ONCE,
// Standard ambiguous here: in 4.6.1 it says that UID in optional,
// while in 4.8.4.7 it says it's REQUIRED. Go with REQUIRED.
'UID' => RFC2445_REQUIRED | RFC2445_ONCE,
'URL' => RFC2445_OPTIONAL | RFC2445_ONCE,
'RECURRENCE-ID' => RFC2445_OPTIONAL | RFC2445_ONCE,
'DTEND' => RFC2445_OPTIONAL | RFC2445_ONCE,
'DURATION' => RFC2445_OPTIONAL | RFC2445_ONCE,
'ATTACH' => RFC2445_OPTIONAL,
'ATTENDEE' => RFC2445_OPTIONAL,
'CATEGORIES' => RFC2445_OPTIONAL,
'COMMENT' => RFC2445_OPTIONAL,
'CONTACT' => RFC2445_OPTIONAL,
'EXDATE' => RFC2445_OPTIONAL,
'EXRULE' => RFC2445_OPTIONAL,
'REQUEST-STATUS' => RFC2445_OPTIONAL,
'RELATED-TO' => RFC2445_OPTIONAL,
'RESOURCES' => RFC2445_OPTIONAL,
'RDATE' => RFC2445_OPTIONAL,
'RRULE' => RFC2445_OPTIONAL,
RFC2445_XNAME => RFC2445_OPTIONAL
);
parent::construct();
}
function invariant_holds() {
// DTEND and DURATION must not appear together
if(isset($this->properties['DTEND']) && isset($this->properties['DURATION'])) {
return false;
}
if(isset($this->properties['DTEND']) && isset($this->properties['DTSTART'])) {
// DTEND must be later than DTSTART
// The standard is not clear on how to hande different value types though
// TODO: handle this correctly even if the value types are different
if($this->properties['DTEND'][0]->value <= $this->properties['DTSTART'][0]->value) {
return false;
}
// DTEND and DTSTART must have the same value type
if($this->properties['DTEND'][0]->val_type != $this->properties['DTSTART'][0]->val_type) {
return false;
}
}
return true;
}
}
class iCalendar_todo extends iCalendar_component {
var $name = 'VTODO';
var $properties;
function construct() {
$this->properties = array(
'class' => RFC2445_OPTIONAL | RFC2445_ONCE,
'completed' => RFC2445_OPTIONAL | RFC2445_ONCE,
'created' => RFC2445_OPTIONAL | RFC2445_ONCE,
'description' => RFC2445_OPTIONAL | RFC2445_ONCE,
'dtstamp' => RFC2445_OPTIONAL | RFC2445_ONCE,
'dtstart' => RFC2445_OPTIONAL | RFC2445_ONCE,
'geo' => RFC2445_OPTIONAL | RFC2445_ONCE,
'last-modified' => RFC2445_OPTIONAL | RFC2445_ONCE,
'location' => RFC2445_OPTIONAL | RFC2445_ONCE,
'organizer' => RFC2445_OPTIONAL | RFC2445_ONCE,
'percent' => RFC2445_OPTIONAL | RFC2445_ONCE,
'priority' => RFC2445_OPTIONAL | RFC2445_ONCE,
'recurid' => RFC2445_OPTIONAL | RFC2445_ONCE,
'sequence' => RFC2445_OPTIONAL | RFC2445_ONCE,
'status' => RFC2445_OPTIONAL | RFC2445_ONCE,
'summary' => RFC2445_OPTIONAL | RFC2445_ONCE,
'uid' => RFC2445_OPTIONAL | RFC2445_ONCE,
'url' => RFC2445_OPTIONAL | RFC2445_ONCE,
'due' => RFC2445_OPTIONAL | RFC2445_ONCE,
'duration' => RFC2445_OPTIONAL | RFC2445_ONCE,
'attach' => RFC2445_OPTIONAL,
'attendee' => RFC2445_OPTIONAL,
'categories' => RFC2445_OPTIONAL,
'comment' => RFC2445_OPTIONAL,
'contact' => RFC2445_OPTIONAL,
'exdate' => RFC2445_OPTIONAL,
'exrule' => RFC2445_OPTIONAL,
'rstatus' => RFC2445_OPTIONAL,
'related' => RFC2445_OPTIONAL,
'resources' => RFC2445_OPTIONAL,
'rdate' => RFC2445_OPTIONAL,
'rrule' => RFC2445_OPTIONAL,
'xprop' => RFC2445_OPTIONAL
);
parent::construct();
// TODO:
// either 'due' or 'duration' may appear in a 'eventprop', but 'due'
// and 'duration' MUST NOT occur in the same 'eventprop'
}
}
class iCalendar_journal extends iCalendar_component {
// TODO: implement
}
class iCalendar_freebusy extends iCalendar_component {
// TODO: implement
}
class iCalendar_alarm extends iCalendar_component {
// TODO: implement
}
class iCalendar_timezone extends iCalendar_component {
var $name = 'VTIMEZONE';
var $properties;
function construct() {
$this->properties = array(
'tzid' => RFC2445_REQUIRED | RFC2445_ONCE,
'last-modified' => RFC2445_OPTIONAL | RFC2445_ONCE,
'tzurl' => RFC2445_OPTIONAL | RFC2445_ONCE,
// TODO: the next two are components of their own!
'standardc' => RFC2445_REQUIRED,
'daylightc' => RFC2445_REQUIRED,
'x-prop' => RFC2445_OPTIONAL
);
parent::construct();
}
}
// REMINDER: DTEND must be later than DTSTART for all components which support both
// REMINDER: DUE must be later than DTSTART for all components which support both