<?php
  /**
   * Copyright (c) 2012 Georg Ehrke <ownclouddev@georgswebsite.de>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  /*
   * This class does import and converts all times to the users current timezone
   */
  class OC_Calendar_Import{
  	/*
  	 * @brief counts the absolute number of parsed elements
  	 */
  	private $abscount;
  
  	/*
  	 * @brief var saves if the percentage should be saved with OC_Cache
  	 */
  	private $cacheprogress;
  
  	/*
  	 * @brief Sabre\VObject\Component\VCalendar object - for documentation see http://code.google.com/p/sabredav/wiki/Sabre_VObject_Component_VCalendar
  	 */
  	private $calobject;
  
  	/*
  	 * @brief var counts the number of imported elements
  	 */
  	private $count;
  
  	/*
  	 * @brief var to check if errors happend while initialization
  	 */
  	private $error;
  
  	/*
  	 * @brief var saves the ical string that was submitted with the __construct function
  	 */
  	private $ical;
  
  	/*
  	 * @brief calendar id for import
  	 */
  	private $id;
  
  	/*
  	 * @brief overwrite flag
  	 */
  	private $overwrite;
  
  	/*
  	 * @brief var saves the percentage of the import's progress
  	 */
  	private $progress;
  
  	/*
  	 * @brief var saves the key for the percentage of the import's progress
  	 */
  	private $progresskey;
  
  	/*
  	 * @brief var saves the timezone the events shell converted to
  	 */
  	private $tz;
  
  	/*
  	 * @brief var saves the userid
  	 */
  	private $userid;
  
  	/*
  	 * public methods
  	 */
  
  	/*
  	 * @brief does general initialization for import object
  	 * @param string $calendar content of ical file
  	 * @param string $tz timezone of the user
  	 * @return boolean
  	 */
  	public function __construct($ical) {
  		$this->error = null;
  		$this->ical = $ical;
  		$this->abscount = 0;
  		$this->count = 0;
  		//fix for multiple subcalendars
  		if(substr_count($ical, 'BEGIN:VCALENDAR') > 1){
  			$ical = substr_replace($ical, '**##++FancyReplacementForFirstOccurrenceOfTheSearchPattern++##**', 0, 15);
  			$ical = str_replace('BEGIN:VCALENDAR', '', $ical);
  			$ical = str_replace('END:VCALENDAR', '', $ical);
  			$ical = substr_replace($ical, 'BEGIN:VCALENDAR', 0, 64);
  			$ical .= "
  " . 'END:VCALENDAR';
  			$this->ical = $ical;
  		}
  		try{
  			$this->calobject = OC_VObject::parse($this->ical);
  		}catch(Exception $e) {
  			//MISSING: write some log
  			$this->error = true;
  			return false;
  		}
  		return true;
  	}
  
  	/*
  	 * @brief imports a calendar
  	 * @return boolean
  	 */
  	public function import() {
  		if(!$this->isValid()) {
  			return false;
  		}
  		$numofcomponents = count($this->calobject->getComponents());
  		if($this->overwrite) {
  			foreach(OC_Calendar_Object::all($this->id) as $obj) {
  				OC_Calendar_Object::delete($obj['id']);
  			}
  		}
  		foreach($this->calobject->getComponents() as $object) {
  			if(!($object instanceof Sabre\VObject\Component\VEvent) && !($object instanceof Sabre\VObject\Component\VJournal) && !($object instanceof Sabre\VObject\Component\VTodo)) {
  				continue;
  			}
  			if(!is_null($object->DTSTART)){
  				$dtend = OC_Calendar_Object::getDTEndFromVEvent($object);
  				if($object->DTEND) {
  					$object->DTEND->setDateTime($dtend->getDateTime(), $object->DTSTART->getDateType());
  				}
  			}
  			$vcalendar = $this->createVCalendar($object->serialize());
  			$insertid = OC_Calendar_Object::add($this->id, $vcalendar);
  			$this->abscount++;
  			if($this->isDuplicate($insertid)) {
  				OC_Calendar_Object::delete($insertid);
  			}else{
  				$this->count++;
  			}
  			$this->updateProgress(intval(($this->abscount / $numofcomponents)*100));
  		}
  		OC_Cache::remove($this->progresskey);
  		return true;
  	}
  
  	/*
  	 * @brief sets the timezone
  	 * @return boolean
  	 */
  	public function setTimeZone($tz) {
  		$this->tz = $tz;
  		return true;
  	}
  
  	/*
  	 * @brief sets the overwrite flag
  	 * @return boolean
  	 */
  	public function setOverwrite($overwrite) {
  		$this->overwrite = (bool) $overwrite;
  		return true;
  	}
  
  	/*
  	 * @brief sets the progresskey
  	 * @return boolean
  	 */
  	public function setProgresskey($progresskey) {
  		$this->progresskey = $progresskey;
  		return true;
  	}
  
  	/*
  	 * @brief checks if something went wrong while initialization
  	 * @return boolean
  	 */
  	public function isValid() {
  		if(is_null($this->error)) {
  			return true;
  		}
  		return false;
  	}
  
  	/*
  	 * @brief returns the percentage of progress
  	 * @return integer
  	 */
  	public function getProgress() {
  		return $this->progress;
  	}
  
  	/*
  	 * @brief enables the cache for the percentage of progress
  	 * @return boolean
  	 */
  	public function enableProgressCache() {
  		$this->cacheprogress = true;
  		return true;
  	}
  
  	/*
  	 * @brief disables the cache for the percentage of progress
  	 * @return boolean
  	 */
  	public function disableProgressCache() {
  		$this->cacheprogress = false;
  		return false;
  	}
  
  	/*
  	 * @brief generates a new calendar name
  	 * @return string
  	 */
  	public function createCalendarName() {
  		$calendars = OC_Calendar_Calendar::allCalendars($this->userid);
  		$calendarname = $guessedcalendarname = !is_null($this->guessCalendarName())?($this->guessCalendarName()):(OC_Calendar_App::$l10n->t('New Calendar'));
  		$i = 1;
  		while(!OC_Calendar_Calendar::isCalendarNameavailable($calendarname, $this->userid)) {
  			$calendarname = $guessedcalendarname . ' (' . $i . ')';
  			$i++;
  		}
  		return $calendarname;
  	}
  
  	/*
  	 * @brief generates a new calendar color
  	 * @return string
  	 */
  	public function createCalendarColor() {
  		if(is_null($this->guessCalendarColor())) {
  			return '#9fc6e7';
  		}
  		return $this->guessCalendarColor();
  	}
  
  	/*
  	 * @brief sets the id for the calendar
  	 * @param integer $id of the calendar
  	 * @return boolean
  	 */
  	public function setCalendarID($id) {
  		$this->id = $id;
  		return true;
  	}
  
  	/*
  	 * @brief sets the userid to import the calendar
  	 * @param string $id of the user
  	 * @return boolean
  	 */
  	public function setUserID($userid) {
  		$this->userid = $userid;
  		return true;
  	}
  
  	/*
  	 * @brief returns the private
  	 * @param string $id of the user
  	 * @return boolean
  	 */
  	public function getCount() {
  		return $this->count;
  	}
  
  	/*
  	 * private methods
  	 */
  
  	/*
  	 * @brief generates an unique ID
  	 * @return string
  	 */
  	//private function createUID() {
  	//	return substr(md5(rand().time()),0,10);
  	//}
  
  	/*
  	 * @brief checks is the UID is already in use for another event
  	 * @param string $uid uid to check
  	 * @return boolean
  	 */
  	//private function isUIDAvailable($uid) {
  	//
  	//}
  
  	/*
  	 * @brief generates a proper VCalendar string
  	 * @param string $vobject
  	 * @return string
  	 */
  	private function createVCalendar($vobject) {
  		if(is_object($vobject)) {
  			$vobject = @$vobject->serialize();
  		}
  		$vcalendar = "BEGIN:VCALENDAR
  VERSION:2.0
  PRODID:ownCloud Calendar " . OCP\App::getAppVersion('calendar') . "
  ";
  		$vcalendar .= $vobject;
  		$vcalendar .= "END:VCALENDAR";
  		return $vcalendar;
  	}
  
  	/*
  	 * @brief checks if an event already exists in the user's calendars
  	 * @param integer $insertid id of the new object
  	 * @return boolean
  	 */
  	private function isDuplicate($insertid) {
  		$newobject = OC_Calendar_Object::find($insertid);
  		$stmt = OCP\DB::prepare('SELECT COUNT(*) AS `count` FROM `*PREFIX*clndr_objects`
  								 INNER JOIN `*PREFIX*clndr_calendars` ON `calendarid`=`*PREFIX*clndr_calendars`.`id`
  								 WHERE `objecttype`=? AND `startdate`=? AND `enddate`=? AND `repeating`=? AND `summary`=? AND `calendardata`=? AND `userid` = ?');
  		$result = $stmt->execute(array($newobject['objecttype'],$newobject['startdate'],$newobject['enddate'],$newobject['repeating'],$newobject['summary'],$newobject['calendardata'], $this->userid));
  		$result = $result->fetchRow();
  		if($result['count'] >= 2) {
  			return true;
  		}
  		return false;
  	}
  
  	/*
  	 * @brief updates the progress var
  	 * @param integer $percentage
  	 * @return boolean
  	 */
  	private function updateProgress($percentage) {
  		$this->progress = $percentage;
  		if($this->cacheprogress) {
  			OC_Cache::set($this->progresskey, $this->progress, 300);
  		}
  		return true;
  	}
  
  	/*
  	 * public methods for (pre)rendering of X-... Attributes
  	 */
  
  	/*
  	 * @brief guesses the calendar color
  	 * @return mixed - string or boolean
  	 */
  	public function guessCalendarColor() {
  		if(!is_null($this->calobject->__get('X-APPLE-CALENDAR-COLOR'))) {
  			return $this->calobject->__get('X-APPLE-CALENDAR-COLOR');
  		}
  		return null;
  	}
  
  	/*
  	 * @brief guesses the calendar description
  	 * @return mixed - string or boolean
  	 */
  	public function guessCalendarDescription() {
  		if(!is_null($this->calobject->__get('X-WR-CALDESC'))) {
  			return $this->calobject->__get('X-WR-CALDESC');
  		}
  		return null;
  	}
  
  	/*
  	 * @brief guesses the calendar name
  	 * @return mixed - string or boolean
  	 */
  	public function guessCalendarName() {
  		if(!is_null($this->calobject->__get('X-WR-CALNAME'))) {
  			return $this->calobject->__get('X-WR-CALNAME');
  		}
  		return null;
  	}
  }