<?php
  /**
   * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */

  namespace OC;

  use OC\Hooks\BasicEmitter;
  
  /**
   * Class that handles autoupdating of ownCloud
   *
   * Hooks provided in scope \OC\Updater
   *  - maintenanceStart()
   *  - maintenanceEnd()
   *  - dbUpgrade()
   *  - filecacheStart()
   *  - filecacheProgress(int $percentage)
   *  - filecacheDone()
   *  - failure(string $message)
   */

  class Updater extends BasicEmitter {
  
  	/**
  	 * @var \OC\Log $log
  	 */
  	private $log;
  
  	/**
  	 * @param \OC\Log $log
  	 */
  	public function __construct($log = null) {
  		$this->log = $log;
  	}

  	/**
  	 * Check if a new version is available

  	 * @param string $updaterUrl the url to check, i.e. 'http://apps.owncloud.com/updater.php'

  	 * @return array | bool
  	 */

  	public function check($updaterUrl) {
  
  		// Look up the cache - it is invalidated all 30 minutes

  		if ((\OC_Appconfig::getValue('core', 'lastupdatedat') + 1800) > time()) {
  			return json_decode(\OC_Appconfig::getValue('core', 'lastupdateResult'), true);
  		}

  		\OC_Appconfig::setValue('core', 'lastupdatedat', time());

  		if (\OC_Appconfig::getValue('core', 'installedat', '') == '') {
  			\OC_Appconfig::setValue('core', 'installedat', microtime(true));
  		}
  
  		$version = \OC_Util::getVersion();
  		$version['installed'] = \OC_Appconfig::getValue('core', 'installedat');
  		$version['updated'] = \OC_Appconfig::getValue('core', 'lastupdatedat');

  		$version['updatechannel'] = \OC_Util::getChannel(); 

  		$version['edition'] = \OC_Util::getEditionString();

  		$version['build'] = \OC_Util::getBuild();

  		$versionString = implode('x', $version);
  
  		//fetch xml data from updater
  		$url = $updaterUrl . '?version=' . $versionString;
  
  		// set a sensible timeout of 10 sec to stay responsive even if the update server is down.
  		$ctx = stream_context_create(
  			array(
  				'http' => array(
  					'timeout' => 10
  				)
  			)
  		);
  		$xml = @file_get_contents($url, 0, $ctx);
  		if ($xml == false) {
  			return array();
  		}

  		$loadEntities = libxml_disable_entity_loader(true);

  		$data = @simplexml_load_string($xml);

  		libxml_disable_entity_loader($loadEntities);

  
  		$tmp = array();
  		$tmp['version'] = $data->version;
  		$tmp['versionstring'] = $data->versionstring;
  		$tmp['url'] = $data->url;
  		$tmp['web'] = $data->web;

  		// Cache the result

  		\OC_Appconfig::setValue('core', 'lastupdateResult', json_encode($data));

  		return $tmp;

  	}
  
  	/**
  	 * runs the update actions in maintenance mode, does not upgrade the source files
  	 */
  	public function upgrade() {
  		\OC_DB::enableCaching(false);
  		\OC_Config::setValue('maintenance', true);
  		$installedVersion = \OC_Config::getValue('version', '0.0.0');
  		$currentVersion = implode('.', \OC_Util::getVersion());

  		if ($this->log) {
  			$this->log->debug('starting upgrade from ' . $installedVersion . ' to ' . $currentVersion, array('app' => 'core'));
  		}
  		$this->emit('\OC\Updater', 'maintenanceStart');

  		// create empty file in data dir, so we can later find
  		// out that this is indeed an ownCloud data directory
  		// (in case it didn't exist before)
  		file_put_contents(\OC_Config::getValue('datadirectory', \OC::$SERVERROOT.'/data').'/.ocdata', '');

  		/*
  		 * START CONFIG CHANGES FOR OLDER VERSIONS
  		 */

  		if (!\OC::$CLI && version_compare($installedVersion, '6.00.4', '<')) {
  			// Add the trusted_domains config if it is not existant

  			// This is added to prevent host header poisoning
  			\OC_Config::setValue('trusted_domains', \OC_Config::getValue('trusted_domains', array(\OC_Request::serverHost()))); 
  		}
  		/*
  		 * STOP CONFIG CHANGES FOR OLDER VERSIONS
  		 */

  		try {
  			\OC_DB::updateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml');

  			$this->emit('\OC\Updater', 'dbUpgrade');

  
  			// do a file cache upgrade for users with files
  			// this can take loooooooooooooooooooooooong
  			$this->upgradeFileCache();
  		} catch (\Exception $exception) {

  			$this->emit('\OC\Updater', 'failure', array($exception->getMessage()));

  		}
  		\OC_Config::setValue('version', implode('.', \OC_Util::getVersion()));
  		\OC_App::checkAppsRequirements();
  		// load all apps to also upgrade enabled apps
  		\OC_App::loadApps();

  
  		$repair = new Repair();
  		$repair->run();

  		//Invalidate update feed
  		\OC_Appconfig::setValue('core', 'lastupdatedat', 0);

  		\OC_Config::setValue('maintenance', false);

  		$this->emit('\OC\Updater', 'maintenanceEnd');

  	}
  
  	private function upgradeFileCache() {
  		try {
  			$query = \OC_DB::prepare('
  				SELECT DISTINCT `user`
  				FROM `*PREFIX*fscache`
  			');
  			$result = $query->execute();

  		} catch (\Exception $e) {

  			return;
  		}
  		$users = $result->fetchAll();
  		if (count($users) == 0) {
  			return;
  		}
  		$step = 100 / count($users);
  		$percentCompleted = 0;
  		$lastPercentCompletedOutput = 0;
  		$startInfoShown = false;
  		foreach ($users as $userRow) {
  			$user = $userRow['user'];
  			\OC\Files\Filesystem::initMountPoints($user);
  			\OC\Files\Cache\Upgrade::doSilentUpgrade($user);
  			if (!$startInfoShown) {
  				//We show it only now, because otherwise Info about upgraded apps
  				//will appear between this and progress info

  				$this->emit('\OC\Updater', 'filecacheStart');

  				$startInfoShown = true;
  			}
  			$percentCompleted += $step;
  			$out = floor($percentCompleted);
  			if ($out != $lastPercentCompletedOutput) {

  				$this->emit('\OC\Updater', 'filecacheProgress', array($out));

  				$lastPercentCompletedOutput = $out;
  			}
  		}

  		$this->emit('\OC\Updater', 'filecacheDone');

  	}

  }