<?php
/**
 * @file index.php
 * Friendica
 */

/**
 * Bootstrap the application
 */

use Friendica\App;
use Friendica\BaseObject;
use Friendica\Content\Nav;
use Friendica\Core\Addon;
use Friendica\Core\Config;
use Friendica\Core\L10n;
use Friendica\Core\Session;
use Friendica\Core\System;
use Friendica\Core\Theme;
use Friendica\Core\Worker;
use Friendica\Database\DBM;
use Friendica\Model\Profile;
use Friendica\Module\Login;

require_once 'boot.php';

$a = new App(__DIR__);
BaseObject::setApp($a);

// We assume that the index.php is called by a frontend process
// The value is set to "true" by default in boot.php
$a->backend = false;

/**
 * Load the configuration file which contains our DB credentials.
 * Ignore errors. If the file doesn't exist or is empty, we are running in
 * installation mode.
 */

$install = ((file_exists('.htconfig.php') && filesize('.htconfig.php')) ? false : true);

// Only load config if found, don't surpress errors
if (!$install) {
	include ".htconfig.php";
}

/**
 * Try to open the database;
 */

require_once "include/dba.php";

if (!$install) {
	$result = dba::connect($db_host, $db_user, $db_pass, $db_data);
	unset($db_host, $db_user, $db_pass, $db_data);

	if (!$result) {
		System::unavailable();
	}

	/**
	 * Load configs from db. Overwrite configs from .htconfig.php
	 */

	Config::load();

	if ($a->max_processes_reached() || $a->maxload_reached()) {
		header($_SERVER["SERVER_PROTOCOL"] . ' 503 Service Temporarily Unavailable');
		header('Retry-After: 120');
		header('Refresh: 120; url=' . System::baseUrl() . "/" . $a->query_string);
		die("System is currently unavailable. Please try again later");
	}

	if (Config::get('system', 'force_ssl') && ($a->get_scheme() == "http")
		&& (intval(Config::get('system', 'ssl_policy')) == SSL_POLICY_FULL)
		&& (substr(System::baseUrl(), 0, 8) == "https://")
		&& ($_SERVER['REQUEST_METHOD'] == 'GET')) {
		header("HTTP/1.1 302 Moved Temporarily");
		header("Location: " . System::baseUrl() . "/" . $a->query_string);
		exit();
	}

	Config::init();
	Session::init();
	Addon::loadHooks();
	Addon::callHooks('init_1');

	$maintenance = Config::get('system', 'maintenance');
}

$lang = L10n::getBrowserLanguage();

L10n::loadTranslationTable($lang);

/**
 * Important stuff we always need to do.
 *
 * The order of these may be important so use caution if you think they're all
 * intertwingled with no logical order and decide to sort it out. Some of the
 * dependencies have changed, but at least at one time in the recent past - the
 * order was critical to everything working properly
 */

// Exclude the backend processes from the session management
if (!$a->is_backend()) {
	$stamp1 = microtime(true);
	session_start();
	$a->save_timestamp($stamp1, "parser");
} else {
	$_SESSION = [];
	Worker::executeIfIdle();
}

/**
 * Language was set earlier, but we can over-ride it in the session.
 * We have to do it here because the session was just now opened.
 */
if (x($_SESSION, 'authenticated') && !x($_SESSION, 'language')) {
	// we haven't loaded user data yet, but we need user language
	$user = dba::selectFirst('user', ['language'], ['uid' => $_SESSION['uid']]);
	$_SESSION['language'] = $lang;
	if (DBM::is_result($user)) {
		$_SESSION['language'] = $user['language'];
	}
}

if ((x($_SESSION, 'language')) && ($_SESSION['language'] !== $lang)) {
	$lang = $_SESSION['language'];
	L10n::loadTranslationTable($lang);
}

if ((x($_GET, 'zrl')) && (!$install && !$maintenance)) {
	// Only continue when the given profile link seems valid
	// Valid profile links contain a path with "/profile/" and no query parameters
	if ((parse_url($_GET['zrl'], PHP_URL_QUERY) == "")
		&& strstr(parse_url($_GET['zrl'], PHP_URL_PATH), "/profile/")
	) {
		$_SESSION['my_url'] = $_GET['zrl'];
		$a->query_string = preg_replace('/[\?&]zrl=(.*?)([\?&]|$)/is', '', $a->query_string);
		Profile::zrlInit($a);
	} else {
		// Someone came with an invalid parameter, maybe as a DDoS attempt
		// We simply stop processing here
		logger("Invalid ZRL parameter ".$_GET['zrl'], LOGGER_DEBUG);
		header('HTTP/1.1 403 Forbidden');
		echo "<h1>403 Forbidden</h1>";
		killme();
	}
}

/**
 * For Mozilla auth manager - still needs sorting, and this might conflict with LRDD header.
 * Apache/PHP lumps the Link: headers into one - and other services might not be able to parse it
 * this way. There's a PHP flag to link the headers because by default this will over-write any other
 * link header.
 *
 * What we really need to do is output the raw headers ourselves so we can keep them separate.
 */

// header('Link: <' . System::baseUrl() . '/amcd>; rel="acct-mgmt";');

Login::sessionAuth();

if (! x($_SESSION, 'authenticated')) {
	header('X-Account-Management-Status: none');
}

/* set up page['htmlhead'] and page['end'] for the modules to use */
$a->page['htmlhead'] = '';
$a->page['end'] = '';

$_SESSION['sysmsg']       = defaults($_SESSION, 'sysmsg'      , []);
$_SESSION['sysmsg_info']  = defaults($_SESSION, 'sysmsg_info' , []);
$_SESSION['last_updated'] = defaults($_SESSION, 'last_updated', []);

/*
 * check_config() is responsible for running update scripts. These automatically
 * update the DB schema whenever we push a new one out. It also checks to see if
 * any addons have been added or removed and reacts accordingly.
 */

// in install mode, any url loads install module
// but we need "view" module for stylesheet
if ($install && $a->module!="view") {
	$a->module = 'install';
} elseif ($maintenance && $a->module!="view") {
	$a->module = 'maintenance';
} else {
	check_url($a);
	check_db(false);
	check_addons($a);
}

Nav::setSelected('nothing');

//Don't populate apps_menu if apps are private
$privateapps = Config::get('config', 'private_addons');
if ((local_user()) || (! $privateapps === "1")) {
	$arr = ['app_menu' => $a->apps];

	Addon::callHooks('app_menu', $arr);

	$a->apps = $arr['app_menu'];
}

/**
 * We have already parsed the server path into $a->argc and $a->argv
 *
 * $a->argv[0] is our module name. We will load the file mod/{$a->argv[0]}.php
 * and use it for handling our URL request.
 * The module file contains a few functions that we call in various circumstances
 * and in the following order:
 *
 * "module"_init
 * "module"_post (only called if there are $_POST variables)
 * "module"_afterpost
 * "module"_content - the string return of this function contains our page body
 *
 * Modules which emit other serialisations besides HTML (XML,JSON, etc.) should do
 * so within the module init and/or post functions and then invoke killme() to terminate
 * further processing.
 */
if (strlen($a->module)) {

	/**
	 * We will always have a module name.
	 * First see if we have an addon which is masquerading as a module.
	 */

	// Compatibility with the Android Diaspora client
	if ($a->module == 'stream') {
		goaway('network?f=&order=post');
	}

	if ($a->module == 'conversations') {
		goaway('message');
	}

	if ($a->module == 'commented') {
		goaway('network?f=&order=comment');
	}

	if ($a->module == 'liked') {
		goaway('network?f=&order=comment');
	}

	if ($a->module == 'activity') {
		goaway('network/?f=&conv=1');
	}

	if (($a->module == 'status_messages') && ($a->cmd == 'status_messages/new')) {
		goaway('bookmarklet');
	}

	if (($a->module == 'user') && ($a->cmd == 'user/edit')) {
		goaway('settings');
	}

	if (($a->module == 'tag_followings') && ($a->cmd == 'tag_followings/manage')) {
		goaway('search');
	}

	// Compatibility with the Firefox App
	if (($a->module == "users") && ($a->cmd == "users/sign_in")) {
		$a->module = "login";
	}

	$privateapps = Config::get('config', 'private_addons');

	if (is_array($a->addons) && in_array($a->module, $a->addons) && file_exists("addon/{$a->module}/{$a->module}.php")) {
		//Check if module is an app and if public access to apps is allowed or not
		if ((!local_user()) && Addon::isApp($a->module) && $privateapps === "1") {
			info(L10n::t("You must be logged in to use addons. "));
		} else {
			include_once "addon/{$a->module}/{$a->module}.php";
			if (function_exists($a->module . '_module')) {
				$a->module_loaded = true;
			}
		}
	}

	// Controller class routing
	if (! $a->module_loaded && class_exists('Friendica\\Module\\' . ucfirst($a->module))) {
		$a->module_class = 'Friendica\\Module\\' . ucfirst($a->module);
		$a->module_loaded = true;
	}

	/**
	 * If not, next look for a 'standard' program module in the 'mod' directory
	 */

	if (! $a->module_loaded && file_exists("mod/{$a->module}.php")) {
		include_once "mod/{$a->module}.php";
		$a->module_loaded = true;
	}

	/**
	 * The URL provided does not resolve to a valid module.
	 *
	 * On Dreamhost sites, quite often things go wrong for no apparent reason and they send us to '/internal_error.html'.
	 * We don't like doing this, but as it occasionally accounts for 10-20% or more of all site traffic -
	 * we are going to trap this and redirect back to the requested page. As long as you don't have a critical error on your page
	 * this will often succeed and eventually do the right thing.
	 *
	 * Otherwise we are going to emit a 404 not found.
	 */

	if (! $a->module_loaded) {
		// Stupid browser tried to pre-fetch our Javascript img template. Don't log the event or return anything - just quietly exit.
		if ((x($_SERVER, 'QUERY_STRING')) && preg_match('/{[0-9]}/', $_SERVER['QUERY_STRING']) !== 0) {
			killme();
		}

		if ((x($_SERVER, 'QUERY_STRING')) && ($_SERVER['QUERY_STRING'] === 'q=internal_error.html') && isset($dreamhost_error_hack)) {
			logger('index.php: dreamhost_error_hack invoked. Original URI =' . $_SERVER['REQUEST_URI']);
			goaway(System::baseUrl() . $_SERVER['REQUEST_URI']);
		}

		logger('index.php: page not found: ' . $_SERVER['REQUEST_URI'] . ' ADDRESS: ' . $_SERVER['REMOTE_ADDR'] . ' QUERY: ' . $_SERVER['QUERY_STRING'], LOGGER_DEBUG);
		header($_SERVER["SERVER_PROTOCOL"] . ' 404 ' . L10n::t('Not Found'));
		$tpl = get_markup_template("404.tpl");
		$a->page['content'] = replace_macros(
			$tpl,
			[
			'$message' =>  L10n::t('Page not found.')]
		);
	}
}

/**
 * Load current theme info
 */
$theme_info_file = "view/theme/".current_theme()."/theme.php";
if (file_exists($theme_info_file)) {
	require_once $theme_info_file;
}


/* initialise content region */

if (! x($a->page, 'content')) {
	$a->page['content'] = '';
}

if (!$install && !$maintenance) {
	Addon::callHooks('page_content_top', $a->page['content']);
}

/**
 * Call module functions
 */

if ($a->module_loaded) {
	$a->page['page_title'] = $a->module;
	$placeholder = '';

	if ($a->module_class) {
		Addon::callHooks($a->module . '_mod_init', $placeholder);
		call_user_func([$a->module_class, 'init']);
	} else if (function_exists($a->module . '_init')) {
		Addon::callHooks($a->module . '_mod_init', $placeholder);
		$func = $a->module . '_init';
		$func($a);
	}

	if (function_exists(str_replace('-', '_', current_theme()) . '_init')) {
		$func = str_replace('-', '_', current_theme()) . '_init';
		$func($a);
	}

	if (! $a->error && $_SERVER['REQUEST_METHOD'] === 'POST') {
		Addon::callHooks($a->module . '_mod_post', $_POST);
		if ($a->module_class) {
			call_user_func([$a->module_class, 'post']);
		} else if (function_exists($a->module . '_post')) {
			$func = $a->module . '_post';
			$func($a);
		}
	}

	if (! $a->error) {
		Addon::callHooks($a->module . '_mod_afterpost', $placeholder);
		if ($a->module_class) {
			call_user_func([$a->module_class, 'afterpost']);
		} else if (function_exists($a->module . '_afterpost')) {
			$func = $a->module . '_afterpost';
			$func($a);
		}
	}

	if (! $a->error) {
		$arr = ['content' => $a->page['content']];
		Addon::callHooks($a->module . '_mod_content', $arr);
		$a->page['content'] = $arr['content'];
		if ($a->module_class) {
			$arr = ['content' => call_user_func([$a->module_class, 'content'])];
		} else if (function_exists($a->module . '_content')) {
			$func = $a->module . '_content';
			$arr = ['content' => $func($a)];
		}
		Addon::callHooks($a->module . '_mod_aftercontent', $arr);
		$a->page['content'] .= $arr['content'];
	}

	if (function_exists(str_replace('-', '_', current_theme()) . '_content_loaded')) {
		$func = str_replace('-', '_', current_theme()) . '_content_loaded';
		$func($a);
	}
}

/*
 * Create the page head after setting the language
 * and getting any auth credentials.
 *
 * Moved init_pagehead() and init_page_end() to after
 * all the module functions have executed so that all
 * theme choices made by the modules can take effect.
 */

$a->init_pagehead();

/*
 * Build the page ending -- this is stuff that goes right before
 * the closing </body> tag
 */
$a->init_page_end();

// If you're just visiting, let javascript take you home
if (x($_SESSION, 'visitor_home')) {
	$homebase = $_SESSION['visitor_home'];
} elseif (local_user()) {
	$homebase = 'profile/' . $a->user['nickname'];
}

if (isset($homebase)) {
	$a->page['content'] .= '<script>var homebase="' . $homebase . '" ; </script>';
}

/*
 * now that we've been through the module content, see if the page reported
 * a permission problem and if so, a 403 response would seem to be in order.
 */
if (stristr(implode("", $_SESSION['sysmsg']), L10n::t('Permission denied'))) {
	header($_SERVER["SERVER_PROTOCOL"] . ' 403 ' . L10n::t('Permission denied.'));
}

/*
 * Report anything which needs to be communicated in the notification area (before the main body)
 */
Addon::callHooks('page_end', $a->page['content']);

/*
 * Add the navigation (menu) template
 */
if ($a->module != 'install' && $a->module != 'maintenance') {
	Nav::build($a);
}

/*
 * Add a "toggle mobile" link if we're using a mobile device
 */
if ($a->is_mobile || $a->is_tablet) {
	if (isset($_SESSION['show-mobile']) && !$_SESSION['show-mobile']) {
		$link = 'toggle_mobile?address=' . curPageURL();
	} else {
		$link = 'toggle_mobile?off=1&address=' . curPageURL();
	}
	$a->page['footer'] = replace_macros(
		get_markup_template("toggle_mobile_footer.tpl"),
		[
			'$toggle_link' => $link,
			'$toggle_text' => L10n::t('toggle mobile')]
	);
}

/**
 * Build the page - now that we have all the components
 */

if (!$a->theme['stylesheet']) {
	$stylesheet = current_theme_url();
} else {
	$stylesheet = $a->theme['stylesheet'];
}

$a->page['htmlhead'] = str_replace('{{$stylesheet}}', $stylesheet, $a->page['htmlhead']);
//$a->page['htmlhead'] = replace_macros($a->page['htmlhead'], array('$stylesheet' => $stylesheet));

if (isset($_GET["mode"]) && (($_GET["mode"] == "raw") || ($_GET["mode"] == "minimal"))) {
	$doc = new DOMDocument();

	$target = new DOMDocument();
	$target->loadXML("<root></root>");

	$content = mb_convert_encoding($a->page["content"], 'HTML-ENTITIES', "UTF-8");

	/// @TODO one day, kill those error-surpressing @ stuff, or PHP should ban it
	@$doc->loadHTML($content);

	$xpath = new DOMXPath($doc);

	$list = $xpath->query("//*[contains(@id,'tread-wrapper-')]");  /* */

	foreach ($list as $item) {
		$item = $target->importNode($item, true);

		// And then append it to the target
		$target->documentElement->appendChild($item);
	}
}

if (isset($_GET["mode"]) && ($_GET["mode"] == "raw")) {
	header("Content-type: text/html; charset=utf-8");

	echo substr($target->saveHTML(), 6, -8);

	killme();
}

$page    = $a->page;
$profile = $a->profile;

header("X-Friendica-Version: " . FRIENDICA_VERSION);
header("Content-type: text/html; charset=utf-8");

if (Config::get('system', 'hsts') && (Config::get('system', 'ssl_policy') == SSL_POLICY_FULL)) {
	header("Strict-Transport-Security: max-age=31536000");
}

// Some security stuff
header('X-Content-Type-Options: nosniff');
header('X-XSS-Protection: 1; mode=block');
header('X-Permitted-Cross-Domain-Policies: none');
header('X-Frame-Options: sameorigin');

// Things like embedded OSM maps don't work, when this is enabled
// header("Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; connect-src 'self'; style-src 'self' 'unsafe-inline'; font-src 'self'; img-src 'self' https: data:; media-src 'self' https:; child-src 'self' https:; object-src 'none'");

/*
 * We use $_GET["mode"] for special page templates. So we will check if we have
 * to load another page template than the default one.
 * The page templates are located in /view/php/ or in the theme directory.
 */
if (isset($_GET["mode"])) {
	$template = Theme::getPathForFile($_GET["mode"] . '.php');
}

// If there is no page template use the default page template
if (empty($template)) {
	$template = Theme::getPathForFile("default.php");
}

/// @TODO Looks unsafe (remote-inclusion), is maybe not but Theme::getPathForFile() uses file_exists() but does not escape anything
require_once $template;

killme();