<?php

  class OC_Connector_Sabre_CalDAV extends \Sabre\CalDAV\Backend\AbstractBackend {

  	/**
  	 * List of CalDAV properties, and how they map to database fieldnames
  	 *
  	 * Add your own properties by simply adding on to this array
  	 *
  	 * @var array
  	 */
  	public $propertyMap = array(
  		'{DAV:}displayname'						  => 'displayname',

  		'{urn:ietf:params:xml:ns:caldav}calendar-description' => 'description',

  		'{urn:ietf:params:xml:ns:caldav}calendar-timezone'	=> 'timezone',
  		'{http://apple.com/ns/ical/}calendar-order'  => 'calendarorder',
  		'{http://apple.com/ns/ical/}calendar-color'  => 'calendarcolor',
  	);
  
  	/**
  	 * Returns a list of calendars for a principal.
  	 *
  	 * Every project is an array with the following keys:
  	 *  * id, a unique id that will be used by other functions to modify the
  	 *	calendar. This can be the same as the uri or a database key.
  	 *  * uri, which the basename of the uri with which the calendar is
  	 *	accessed.
  	 *  * principalUri. The owner of the calendar. Almost always the same as
  	 *	principalUri passed to this method.
  	 *
  	 * Furthermore it can contain webdav properties in clark notation. A very
  	 * common one is '{DAV:}displayname'.
  	 *
  	 * @param string $principalUri
  	 * @return array
  	 */
  	public function getCalendarsForUser($principalUri) {
  		$raw = OC_Calendar_Calendar::allCalendarsWherePrincipalURIIs($principalUri);
  
  		$calendars = array();
  		foreach( $raw as $row ) {
  			$components = explode(',',$row['components']);
  
  			if($row['userid'] != OCP\USER::getUser()) {
  				$row['uri'] = $row['uri'] . '_shared_by_' . $row['userid'];
  			}
  			$calendar = array(
  				'id' => $row['id'],
  				'uri' => $row['uri'],
  				'principaluri' => 'principals/'.$row['userid'],

  				'{' . \Sabre\CalDAV\Plugin::NS_CALENDARSERVER . '}getctag' => $row['ctag']?$row['ctag']:'0',
  				'{' . \Sabre\CalDAV\Plugin::NS_CALDAV . '}supported-calendar-component-set'
  					=> new \Sabre\CalDAV\Property\SupportedCalendarComponentSet($components),

  			);
  
  			foreach($this->propertyMap as $xmlName=>$dbName) {

  				$calendar[$xmlName] = isset($row[$dbName]) ? $row[$dbName] : '';

  			}
  
  			$calendars[] = $calendar;
  		}
  		if(\OCP\App::isEnabled('contacts')) {
  			$ctag = 0;
  			$app = new \OCA\Contacts\App();
  			$addressBooks = $app->getAddressBooksForUser();
  			foreach($addressBooks as $addressBook) {
  				$tmp = $addressBook->lastModified();
  				if(!is_null($tmp)) {
  					$ctag = max($ctag, $tmp);
  				}
  			}

  			$ctag++;

  			$calendars[] = array(
  				'id' => 'contact_birthdays',
  				'uri' => 'contact_birthdays',
  				'{DAV:}displayname' => (string)OC_Calendar_App::$l10n->t('Contact birthdays'),
  				'principaluri' => 'principals/contact_birthdays',

  				'{' . \Sabre\CalDAV\Plugin::NS_CALENDARSERVER . '}getctag' => $ctag,
  				'{' . \Sabre\CalDAV\Plugin::NS_CALDAV . '}supported-calendar-component-set'
  					=> new \Sabre\CalDAV\Property\SupportedCalendarComponentSet(array('VEVENT')),

  			);
  		}
  		return $calendars;
  	}
  
  	/**
  	 * Creates a new calendar for a principal.
  	 *
  	 * If the creation was a success, an id must be returned that can be used to reference
  	 * this calendar in other methods, such as updateCalendar
  	 *
  	 * @param string $principalUri
  	 * @param string $calendarUri
  	 * @param array $properties
  	 * @return mixed
  	 */
  	public function createCalendar($principalUri,$calendarUri, array $properties) {
  		$fieldNames = array(
  			'principaluri',
  			'uri',
  			'ctag',
  		);
  		$values = array(
  			':principaluri' => $principalUri,
  			':uri'		  => $calendarUri,
  			':ctag'		 => 1,
  		);
  
  		// Default value
  		$sccs = '{urn:ietf:params:xml:ns:caldav}supported-calendar-component-set';
  		$fieldNames[] = 'components';
  		if (!isset($properties[$sccs])) {
  			$values[':components'] = 'VEVENT,VTODO';
  		} else {

  			if (!($properties[$sccs] instanceof \Sabre\CalDAV\Property\SupportedCalendarComponentSet)) {
  				throw new \Sabre\DAV\Exception('The ' . $sccs . ' property must be of type: \Sabre\CalDAV\Property\SupportedCalendarComponentSet');

  			}
  			$values[':components'] = implode(',',$properties[$sccs]->getValue());
  		}
  
  		foreach($this->propertyMap as $xmlName=>$dbName) {
  			if (isset($properties[$xmlName])) {
  
  				$myValue = $properties[$xmlName];
  				$values[':' . $dbName] = $properties[$xmlName];
  				$fieldNames[] = $dbName;
  			}
  		}
  
  		if(!isset($newValues['displayname'])) $newValues['displayname'] = 'unnamed';
  		if(!isset($newValues['components'])) $newValues['components'] = 'VEVENT,VTODO';
  		if(!isset($newValues['timezone'])) $newValues['timezone'] = null;
  		if(!isset($newValues['calendarorder'])) $newValues['calendarorder'] = 0;
  		if(!isset($newValues['calendarcolor'])) $newValues['calendarcolor'] = null;
  		if(!is_null($newValues['calendarcolor']) && strlen($newValues['calendarcolor']) == 9) {
  			$newValues['calendarcolor'] = substr($newValues['calendarcolor'], 0, 7);
  		}
  
  		return OC_Calendar_Calendar::addCalendarFromDAVData($principalUri,$calendarUri,$newValues['displayname'],$newValues['components'],$newValues['timezone'],$newValues['calendarorder'],$newValues['calendarcolor']);
  	}
  
  	/**
  	 * Updates a calendars properties
  	 *
  	 * The properties array uses the propertyName in clark-notation as key,
  	 * and the array value for the property value. In the case a property
  	 * should be deleted, the property value will be null.
  	 *
  	 * This method must be atomic. If one property cannot be changed, the
  	 * entire operation must fail.
  	 *
  	 * If the operation was successful, true can be returned.
  	 * If the operation failed, false can be returned.
  	 *
  	 * Deletion of a non-existant property is always succesful.
  	 *
  	 * Lastly, it is optional to return detailed information about any
  	 * failures. In this case an array should be returned with the following
  	 * structure:
  	 *
  	 * array(
  	 *   403 => array(
  	 *	  '{DAV:}displayname' => null,
  	 *   ),
  	 *   424 => array(
  	 *	  '{DAV:}owner' => null,
  	 *   )
  	 * )
  	 *
  	 * In this example it was forbidden to update {DAV:}displayname.
  	 * (403 Forbidden), which in turn also caused {DAV:}owner to fail
  	 * (424 Failed Dependency) because the request needs to be atomic.
  	 *
  	 * @param string $calendarId
  	 * @param array $properties
  	 * @return bool|array
  	 */
  	public function updateCalendar($calendarId, array $properties) {
  
  		$newValues = array();
  		$result = array(
  			200 => array(), // Ok
  			403 => array(), // Forbidden
  			424 => array(), // Failed Dependency
  		);
  
  		$hasError = false;
  
  		foreach($properties as $propertyName=>$propertyValue) {
  
  			// We don't know about this property.
  			if (!isset($this->propertyMap[$propertyName])) {
  				$hasError = true;
  				$result[403][$propertyName] = null;
  				unset($properties[$propertyName]);
  				continue;
  			}
  
  			$fieldName = $this->propertyMap[$propertyName];
  			$newValues[$fieldName] = $propertyValue;
  
  		}
  
  		// If there were any errors we need to fail the request
  		if ($hasError) {
  			// Properties has the remaining properties
  			foreach($properties as $propertyName=>$propertyValue) {
  				$result[424][$propertyName] = null;
  			}
  
  			// Removing unused statuscodes for cleanliness
  			foreach($result as $status=>$properties) {
  				if (is_array($properties) && count($properties)===0) unset($result[$status]);
  			}
  
  			return $result;
  
  		}
  
  		// Success
  		if(!isset($newValues['displayname'])) $newValues['displayname'] = null;
  		if(!isset($newValues['timezone'])) $newValues['timezone'] = null;
  		if(!isset($newValues['calendarorder'])) $newValues['calendarorder'] = null;
  		if(!isset($newValues['calendarcolor'])) $newValues['calendarcolor'] = null;
  		if(!is_null($newValues['calendarcolor']) && strlen($newValues['calendarcolor']) == 9) {
  			$newValues['calendarcolor'] = substr($newValues['calendarcolor'], 0, 7);
  		}
  
  		OC_Calendar_Calendar::editCalendar($calendarId,$newValues['displayname'],null,$newValues['timezone'],$newValues['calendarorder'],$newValues['calendarcolor']);
  
  		return true;
  
  	}
  
  	/**
  	 * Delete a calendar and all it's objects
  	 *
  	 * @param string $calendarId
  	 * @return void
  	 */
  	public function deleteCalendar($calendarId) {
  	    if(preg_match( '=iCal/[1-4]?.*Mac OS X/10.[1-6](.[0-9])?=', $_SERVER['HTTP_USER_AGENT'] )) {

  	    	throw new \Sabre\DAV\Exception\Forbidden("Action is not possible with OSX 10.6.x", 403);

  		}
  
  		OC_Calendar_Calendar::deleteCalendar($calendarId);
  	}
  
  	/**
  	 * Returns all calendar objects within a calendar object.
  	 *
  	 * Every item contains an array with the following keys:
  	 *   * id - unique identifier which will be used for subsequent updates
  	 *   * calendardata - The iCalendar-compatible calnedar data
  	 *   * uri - a unique key which will be used to construct the uri. This can be any arbitrary string.
  	 *   * lastmodified - a timestamp of the last modification time
  	 *   * etag - An arbitrary string, surrounded by double-quotes. (e.g.:
  	 *   '  "abcdef"')
  	 *   * calendarid - The calendarid as it was passed to this function.
  	 *
  	 * Note that the etag is optional, but it's highly encouraged to return for
  	 * speed reasons.
  	 *
  	 * The calendardata is also optional. If it's not returned
  	 * 'getCalendarObject' will be called later, which *is* expected to return
  	 * calendardata.
  	 *
  	 * @param string $calendarId
  	 * @return array
  	 */
  	public function getCalendarObjects($calendarId) {
  		$data = array();
  		if($calendarId === 'contact_birthdays') {
  			$app = new \OCA\Contacts\App();
  			$addressBooks = $app->getAddressBooksForUser();
  			foreach($addressBooks as $addressBook) {
  				foreach($addressBook->getChildren() as $contact) {
  					$vevent = $contact->getBirthdayEvent();
  					if(is_null($vevent)) {
  						continue;
  					}
  					$data[] = $this->OCAddETag(array(
  						'id' => 0,
  						'calendarid' => 'contact_birthdays',

  						'uri' => $addressBook->getBackend()->name.'::'.$addressBook->getId().'::'.$contact->getId().'.ics',

  						'lastmodified' => $contact->lastModified(),
  						'summary' => $vevent->SUMMARY,
  						'calendardata' => $vevent->serialize()
  					));
  				}
  			}
  		} else {
  			foreach(OC_Calendar_Object::all($calendarId) as $row) {
  				$data[] = $this->OCAddETag($row);
  			}
  		}
  		return $data;
  	}
  
  	/**
  	 * Returns information from a single calendar object, based on it's object
  	 * uri.
  	 *
  	 * The returned array must have the same keys as getCalendarObjects. The
  	 * 'calendardata' object is required here though, while it's not required
  	 * for getCalendarObjects.
  	 *
  	 * @param string $calendarId
  	 * @param string $objectUri
  	 * @return array
  	 */
  	public function getCalendarObject($calendarId,$objectUri) {
  		if($calendarId === 'contact_birthdays') {

  			$objectUri = substr($objectUri, 0, (strlen($objectUri) - 4));

  			$objectUriArray = explode('::', $objectUri);
  			if(count($objectUriArray) === 3) {
  				$app = new \OCA\Contacts\App();
  				list($backend, $addressBookId, $contactId) = $objectUriArray;
  				$contact = $app->getContact($backend, $addressBookId, $contactId);
  				$vevent = $contact->getBirthdayEvent();
  				if(is_null($vevent)) {
  					return false;
  				}
  				return $this->OCAddETag(array(
  					'id' => 0,
  					'calendarid' => 'contact_birthdays',

  					'uri' => $contact->getBackend()->name.'::'.$contact->getParent()->getId().'::'.$contact->getId().'.ics',

  					'lastmodified' => $contact->lastModified(),
  					'calendardata' => $vevent->serialize()
  				));
  			}
  		}
  		$data = OC_Calendar_Object::findWhereDAVDataIs($calendarId,$objectUri);
  		if(is_array($data)) {
  			$data = $this->OCAddETag($data);
  			$object = OC_VObject::parse($data['calendardata']);
  			if(!$object) {
  				return false;
  			}
  			$object = OC_Calendar_Object::cleanByAccessClass($data['id'], $object);
  			$data['calendardata'] = $object->serialize();
  		}
  		return $data;
  	}
  
  	/**
  	 * Creates a new calendar object.
  	 *
  	 * @param string $calendarId
  	 * @param string $objectUri
  	 * @param string $calendarData
  	 * @return void
  	 */
  	public function createCalendarObject($calendarId,$objectUri,$calendarData) {
  		OC_Calendar_Object::addFromDAVData($calendarId,$objectUri,$calendarData);
  	}
  
  	/**
  	 * Updates an existing calendarobject, based on it's uri.
  	 *
  	 * @param string $calendarId
  	 * @param string $objectUri
  	 * @param string $calendarData
  	 * @return void
  	 */
  	public function updateCalendarObject($calendarId,$objectUri,$calendarData) {
  		OC_Calendar_Object::editFromDAVData($calendarId,$objectUri,$calendarData);
  	}
  
  	/**
  	 * Deletes an existing calendar object.
  	 *
  	 * @param string $calendarId
  	 * @param string $objectUri
  	 * @return void
  	 */
  	public function deleteCalendarObject($calendarId,$objectUri) {
  		OC_Calendar_Object::deleteFromDAVData($calendarId,$objectUri);
  	}
  
  	/**
  	 * @brief Creates a etag
  	 * @param array $row Database result
  	 * @returns associative array
  	 *
  	 * Adds a key "etag" to the row
  	 */
  	private function OCAddETag($row) {
  		$row['etag'] = '"'.md5($row['calendarid'].$row['uri'].$row['calendardata'].$row['lastmodified']).'"';
  		return $row;
  	}
  }