<?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.
   */
  
  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 OC_Updater extends BasicEmitter {
  	/**
  	 * Check if a new version is available
  	 * @param string $updateUrl the url to check, i.e. 'http://apps.owncloud.com/updater.php'
  	 * @return array | bool
  	 */
  	static public function check($updaterUrl='http://apps.owncloud.com/updater.php') {
  		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'] = 'stable';
  		$version['edition'] = \OC_Util::getEditionString();
  		$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();
  		}
  		$data = @simplexml_load_string($xml);
  
  		$tmp = array();
  		$tmp['version'] = $data->version;
  		$tmp['versionstring'] = $data->versionstring;
  		$tmp['url'] = $data->url;
  		$tmp['web'] = $data->web;
  
  		\OC_Appconfig::setValue('core', 'lastupdateResult', json_encode($data));
  		return $tmp;
  	}
  
  	public static function ShowUpdatingHint() {
  		$l = OC_L10N::get('lib');
  
  		if(OC_Config::getValue('updatechecker', true)==true) {
  			$data=OC_Updater::check();
  			if(isset($data['version']) && !empty($data['version'])) {
  				$txt='<span style="color:#AA0000; font-weight:bold;">'
  				.$l->t('%s is available. Get <a href="%s">more information</a>',
  				array($data['versionstring'], $data['web'])).'</span>';
  			}else{
  				$txt=$l->t('up to date');
  			}
  		} else {
  			$txt=$l->t('updates check is disabled');
  		}
  		return($txt);
  	}
  
  	/**
  	 * 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());
  		\OC_Log::write('core', 'starting upgrade from ' . $installedVersion . ' to ' . $currentVersion, \OC_Log::WARN);
  		$this->emit('\OC_Updater', 'maintenanceStart');
  		try {
  			\OC_DB::updateDbFromStructure(\OC::$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();
  		\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 = $query->execute();
  			if(\OCP\DB::isError($result)) {
  				//MDB2 does not throw Exception by itself
  				throw new \Exception($result->getMessage());
  			}
  		} catch (\Exception $e) {
  			//No such table, i.e. filecache upgrade already proceeded
  			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');
  	}
  }