<?php
/**
 * @copyright Copyright (c) 2016, ownCloud, Inc.
 *
 * @author Bart Visscher <bartv@thisnet.nl>
 * @author Brice Maron <brice@bmaron.net>
 * @author Frank Karlitschek <frank@karlitschek.de>
 * @author Hendrik Leppelsack <hendrik@leppelsack.de>
 * @author Individual IT Services <info@individual-it.net>
 * @author Jakob Sack <mail@jakobsack.de>
 * @author Jan-Christoph Borchardt <hey@jancborchardt.net>
 * @author Joas Schilling <coding@schilljs.com>
 * @author Jörn Friedrich Dreyer <jfd@butonic.de>
 * @author Lukas Reschke <lukas@statuscode.ch>
 * @author Michael Letzgus <develope@michael-letzgus.de>
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Raghu Nayyar <hey@raghunayyar.com>
 * @author Robin Appelman <robin@icewind.nl>
 * @author Roeland Jago Douma <roeland@famdouma.nl>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 * @author Vincent Petry <pvince81@owncloud.com>
 *
 * @license AGPL-3.0
 *
 * This code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License, version 3,
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 *
 */

use OC\TemplateLayout;

require_once __DIR__.'/template/functions.php';

/**
 * This class provides the templates for ownCloud.
 */
class OC_Template extends \OC\Template\Base {

	/** @var string */
	private $renderAs; // Create a full page?

	/** @var string */
	private $path; // The path to the template

	/** @var array */
	private $headers = array(); //custom headers

	/** @var string */
	protected $app; // app id

	protected static $initTemplateEngineFirstRun = true;

	/**
	 * Constructor
	 *
	 * @param string $app app providing the template
	 * @param string $name of the template file (without suffix)
	 * @param string $renderAs If $renderAs is set, OC_Template will try to
	 *                         produce a full page in the according layout. For
	 *                         now, $renderAs can be set to "guest", "user" or
	 *                         "admin".
	 * @param bool $registerCall = true
	 */
	public function __construct( $app, $name, $renderAs = "", $registerCall = true ) {
		// Read the selected theme from the config file
		self::initTemplateEngine($renderAs);

		$theme = OC_Util::getTheme();

		$requestToken = (OC::$server->getSession() && $registerCall) ? \OCP\Util::callRegister() : '';

		$parts = explode('/', $app); // fix translation when app is something like core/lostpassword
		$l10n = \OC::$server->getL10N($parts[0]);
		/** @var \OCP\Defaults $themeDefaults */
		$themeDefaults = \OC::$server->query(\OCP\Defaults::class);

		list($path, $template) = $this->findTemplate($theme, $app, $name);

		// Set the private data
		$this->renderAs = $renderAs;
		$this->path = $path;
		$this->app = $app;

		parent::__construct($template, $requestToken, $l10n, $themeDefaults);
	}

	/**
	 * @param string $renderAs
	 */
	public static function initTemplateEngine($renderAs) {
		if (self::$initTemplateEngineFirstRun){

			//apps that started before the template initialization can load their own scripts/styles
			//so to make sure this scripts/styles here are loaded first we use OC_Util::addScript() with $prepend=true
			//meaning the last script/style in this list will be loaded first
			if (\OC::$server->getSystemConfig()->getValue ('installed', false) && $renderAs !== 'error' && !\OCP\Util::needUpgrade()) {
				if (\OC::$server->getConfig ()->getAppValue ( 'core', 'backgroundjobs_mode', 'ajax' ) == 'ajax') {
					OC_Util::addScript ( 'backgroundjobs', null, true );
				}
			}

			OC_Util::addStyle('jquery-ui-fixes',null,true);
			OC_Util::addVendorStyle('jquery-ui/themes/base/jquery-ui',null,true);
			OC_Util::addStyle('server', null, true);
			OC_Util::addVendorStyle('select2/select2', null, true);
			OC_Util::addStyle('jquery.ocdialog');
			OC_Util::addTranslations("core", null, true);
			OC_Util::addScript('search', 'search', true);
			OC_Util::addScript('merged-template-prepend', null, true);
			OC_Util::addScript('jquery-ui-fixes');
			OC_Util::addScript('files/fileinfo');
			OC_Util::addScript('files/client');
			OC_Util::addScript('contactsmenu');

			if (\OC::$server->getConfig()->getSystemValue('debug')) {
				// Add the stuff we need always
				// following logic will import all vendor libraries that are
				// specified in core/js/core.json
				$fileContent = file_get_contents(OC::$SERVERROOT . '/core/js/core.json');
				if($fileContent !== false) {
					$coreDependencies = json_decode($fileContent, true);
					foreach(array_reverse($coreDependencies['vendor']) as $vendorLibrary) {
						//remove trailing ".js" as addVendorScript will append it
						OC_Util::addVendorScript(
							substr($vendorLibrary, 0, strlen($vendorLibrary) - 3),null,true);
						}
 				} else {
					throw new \Exception('Cannot read core/js/core.json');
				}
			} else {
				// Import all (combined) default vendor libraries
				OC_Util::addVendorScript('core', null, true);
			}

			if (\OC::$server->getRequest()->isUserAgent([\OC\AppFramework\Http\Request::USER_AGENT_IE])) {
				// polyfill for btoa/atob for IE friends
				OC_Util::addVendorScript('base64/base64');
				// shim for the davclient.js library
				\OCP\Util::addScript('files/iedavclient');
			}

			self::$initTemplateEngineFirstRun = false;
		}

	}


	/**
	 * find the template with the given name
	 * @param string $name of the template file (without suffix)
	 *
	 * Will select the template file for the selected theme.
	 * Checking all the possible locations.
	 * @param string $theme
	 * @param string $app
	 * @return string[]
	 */
	protected function findTemplate($theme, $app, $name) {
		// Check if it is a app template or not.
		if( $app !== '' ) {
			$dirs = $this->getAppTemplateDirs($theme, $app, OC::$SERVERROOT, OC_App::getAppPath($app));
		} else {
			$dirs = $this->getCoreTemplateDirs($theme, OC::$SERVERROOT);
		}
		$locator = new \OC\Template\TemplateFileLocator( $dirs );
		$template = $locator->find($name);
		$path = $locator->getPath();
		return array($path, $template);
	}

	/**
	 * Add a custom element to the header
	 * @param string $tag tag name of the element
	 * @param array $attributes array of attributes for the element
	 * @param string $text the text content for the element. If $text is null then the
	 * element will be written as empty element. So use "" to get a closing tag.
	 */
	public function addHeader($tag, $attributes, $text=null) {
		$this->headers[]= array(
			'tag' => $tag,
			'attributes' => $attributes,
			'text' => $text
		);
	}

	/**
	 * Process the template
	 * @return boolean|string
	 *
	 * This function process the template. If $this->renderAs is set, it
	 * will produce a full page.
	 */
	public function fetchPage($additionalParams = null) {
		$data = parent::fetchPage($additionalParams);

		if( $this->renderAs ) {
			$page = new TemplateLayout($this->renderAs, $this->app);

			// Add custom headers
			$headers = '';
			foreach(OC_Util::$headers as $header) {
				$headers .= '<'.\OCP\Util::sanitizeHTML($header['tag']);
				if ( strcasecmp($header['tag'], 'script') === 0 && in_array('src', array_map('strtolower', array_keys($header['attributes']))) ) {
					$headers .= ' defer';
				}
				foreach($header['attributes'] as $name=>$value) {
					$headers .= ' '.\OCP\Util::sanitizeHTML($name).'="'.\OCP\Util::sanitizeHTML($value).'"';
				}
				if ($header['text'] !== null) {
					$headers .= '>'.\OCP\Util::sanitizeHTML($header['text']).'</'.\OCP\Util::sanitizeHTML($header['tag']).'>';
				} else {
					$headers .= '/>';
				}
			}

			$page->assign('headers', $headers);

			$page->assign('content', $data);
			return $page->fetchPage();
		}

		return $data;
	}

	/**
	 * Include template
	 *
	 * @param string $file
	 * @param array|null $additionalParams
	 * @return string returns content of included template
	 *
	 * Includes another template. use <?php echo $this->inc('template'); ?> to
	 * do this.
	 */
	public function inc( $file, $additionalParams = null ) {
		return $this->load($this->path.$file.'.php', $additionalParams);
	}

	/**
	 * Shortcut to print a simple page for users
	 * @param string $application The application we render the template for
	 * @param string $name Name of the template
	 * @param array $parameters Parameters for the template
	 * @return boolean|null
	 */
	public static function printUserPage( $application, $name, $parameters = array() ) {
		$content = new OC_Template( $application, $name, "user" );
		foreach( $parameters as $key => $value ) {
			$content->assign( $key, $value );
		}
		print $content->printPage();
	}

	/**
	 * Shortcut to print a simple page for admins
	 * @param string $application The application we render the template for
	 * @param string $name Name of the template
	 * @param array $parameters Parameters for the template
	 * @return bool
	 */
	public static function printAdminPage( $application, $name, $parameters = array() ) {
		$content = new OC_Template( $application, $name, "admin" );
		foreach( $parameters as $key => $value ) {
			$content->assign( $key, $value );
		}
		return $content->printPage();
	}

	/**
	 * Shortcut to print a simple page for guests
	 * @param string $application The application we render the template for
	 * @param string $name Name of the template
	 * @param array|string $parameters Parameters for the template
	 * @return bool
	 */
	public static function printGuestPage( $application, $name, $parameters = array() ) {
		$content = new OC_Template( $application, $name, "guest" );
		foreach( $parameters as $key => $value ) {
			$content->assign( $key, $value );
		}
		return $content->printPage();
	}

	/**
		* Print a fatal error page and terminates the script
		* @param string $error_msg The error message to show
		* @param string $hint An optional hint message - needs to be properly escaped
		*/
	public static function printErrorPage( $error_msg, $hint = '' ) {
		if (\OC_App::isEnabled('theming') && !\OC_App::isAppLoaded('theming')) {
			\OC_App::loadApp('theming');
		}


		if ($error_msg === $hint) {
			// If the hint is the same as the message there is no need to display it twice.
			$hint = '';
		}

		try {
			$content = new \OC_Template( '', 'error', 'error', false );
			$errors = array(array('error' => $error_msg, 'hint' => $hint));
			$content->assign( 'errors', $errors );
			$content->printPage();
		} catch (\Exception $e) {
			$logger = \OC::$server->getLogger();
			$logger->error("$error_msg $hint", ['app' => 'core']);
			$logger->logException($e, ['app' => 'core']);

			header(self::getHttpProtocol() . ' 500 Internal Server Error');
			header('Content-Type: text/plain; charset=utf-8');
			print("$error_msg $hint");
		}
		die();
	}

	/**
	 * print error page using Exception details
	 * @param Exception | Throwable $exception
	 */
	public static function printExceptionErrorPage($exception, $fetchPage = false) {
		try {
			$request = \OC::$server->getRequest();
			$content = new \OC_Template('', 'exception', 'error', false);
			$content->assign('errorClass', get_class($exception));
			$content->assign('errorMsg', $exception->getMessage());
			$content->assign('errorCode', $exception->getCode());
			$content->assign('file', $exception->getFile());
			$content->assign('line', $exception->getLine());
			$content->assign('trace', $exception->getTraceAsString());
			$content->assign('debugMode', \OC::$server->getSystemConfig()->getValue('debug', false));
			$content->assign('remoteAddr', $request->getRemoteAddress());
			$content->assign('requestID', $request->getId());
			if ($fetchPage) {
				return $content->fetchPage();
			}
			$content->printPage();
		} catch (\Exception $e) {
			$logger = \OC::$server->getLogger();
			$logger->logException($exception, ['app' => 'core']);
			$logger->logException($e, ['app' => 'core']);

			header(self::getHttpProtocol() . ' 500 Internal Server Error');
			header('Content-Type: text/plain; charset=utf-8');
			print("Internal Server Error\n\n");
			print("The server encountered an internal error and was unable to complete your request.\n");
			print("Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.\n");
			print("More details can be found in the server log.\n");
		}
		die();
	}

	/**
	 * This is only here to reduce the dependencies in case of an exception to
	 * still be able to print a plain error message.
	 *
	 * Returns the used HTTP protocol.
	 *
	 * @return string HTTP protocol. HTTP/2, HTTP/1.1 or HTTP/1.0.
	 * @internal Don't use this - use AppFramework\Http\Request->getHttpProtocol instead
	 */
	protected static function getHttpProtocol() {
		$claimedProtocol = strtoupper($_SERVER['SERVER_PROTOCOL']);
		$validProtocols = [
			'HTTP/1.0',
			'HTTP/1.1',
			'HTTP/2',
		];
		if(in_array($claimedProtocol, $validProtocols, true)) {
			return $claimedProtocol;
		}
		return 'HTTP/1.1';
	}
}