MyShaarli/index.php

<?php
// Shaarli 0.0.41 beta - Shaare your links...
// The personal, minimalist, super-fast, no-database delicious clone. By sebsauvage.net
// http://sebsauvage.net/wiki/doku.php?id=php:shaarli
// Licence: http://www.opensource.org/licenses/zlib-license.php
// Requires: php 5.1.x  (but autocomplete fields will only work if you have php 5.2.x)
// -----------------------------------------------------------------------------------------------
ini_set('display_errors', false); // Full Path Disclosure https://github.com/sebsauvage/Shaarli/issues/222
// NEVER TRUST IN PHP.INI
// Some hosts do not define a default timezone in php.ini,
// so we have to do this for avoid the strict standard error.
date_default_timezone_set('UTC');

// -----------------------------------------------------------------------------------------------
// Hardcoded parameter (These parameters can be overwritten by creating the file /YourDataDir/options.php see next line)
$GLOBALS['config']['DATADIR'] = 'data'; // Data subdirectory
$GLOBALS['config']['CONFIG_FILE'] = $GLOBALS['config']['DATADIR'].'/config.php'; // Configuration file (user login/password)
$GLOBALS['config']['DATASTORE'] = $GLOBALS['config']['DATADIR'].'/datastore.php'; // Data storage file.
$GLOBALS['config']['LINKS_PER_PAGE'] = 20; // Default links per page.
$GLOBALS['config']['IPBANS_FILENAME'] = $GLOBALS['config']['DATADIR'].'/ipbans.php'; // File storage for failures and bans.
$GLOBALS['config']['BAN_AFTER'] = 4;        // Ban IP after this many failures.
$GLOBALS['config']['BAN_DURATION'] = 1800;  // Ban duration for IP address after login failures (in seconds) (1800 sec. = 30 minutes)
$GLOBALS['config']['OPEN_SHAARLI'] = false; // If true, anyone can add/edit/delete links without having to login
$GLOBALS['config']['HIDE_TIMESTAMPS'] = false; // If true, the moment when links were saved are not shown to users that are not logged in.
$GLOBALS['config']['ENABLE_THUMBNAILS'] = true; // Enable thumbnails in links.
$GLOBALS['config']['ENABLE_FAVICON'] = true; // Enable favicon in links.
$GLOBALS['config']['CACHEDIR'] = 'cache'; // Cache directory for thumbnails for SLOW services (like flickr)
$GLOBALS['config']['PAGECACHE'] = 'pagecache'; // Page cache directory.
$GLOBALS['config']['ENABLE_LOCALCACHE'] = true; // Enable Shaarli to store thumbnail in a local cache. Disable to reduce webspace usage.
                                                // Care if favicon is active and local cache are false serve page can be long
$GLOBALS['config']['PUBSUBHUB_URL'] = ''; // PubSubHubbub support. Put an empty string to disable, or put your hub url here to enable.
                                          // Note: You must have publisher.php in the same directory as Shaarli index.php
$GLOBALS['config']['UPDATECHECK_FILENAME'] = $GLOBALS['config']['DATADIR'].'/lastupdatecheck.txt'; // For updates check of Shaarli.
$GLOBALS['config']['UPDATECHECK_INTERVAL'] = 86400; // Updates check frequency for Shaarli. 86400 seconds=24 hours
$GLOBALS['config']['UPDATECHECK_URL'] = 'https://book.knah-tsaeb.org/shaarli_version.txt'; // Define last version of myShaarli
$GLOBALS['config']['UPDATECHECK_DOWNLOAD'] = 'https://forge.leslibres.org/Knah-Tsaeb/MyShaarli';
$GLOBALS['config']['ENABLE_UPDATECHECK'] = true;
$GLOBALS['config']['externalThumbshot'] = ''; // Url for external thumbnailer
                                              // exemple : http://images.thumbshots.com/image.aspx?cid=dgdfgdfg&v=1&w=120&url=
                                              // the last param must be a url
$GLOBALS['config']['ENABLE_MARKDOWN'] = true;
$GLOBALS['config']['WALLABAG_URL'] = '';
$GLOBALS['config']['WALLABAG_VERSION'] = ''; // 1 for V1 or 2 for v2
$GLOBALS['config']['contactLink'] = ''; // Define link for contact Example : http://example.com/contact.php or mailo:contact@example.com
$GLOBALS['config']['THEME'] = 'myShaarli';
$GLOBALS['config']['DATE_FORMAT'] = '%A %d %B %Y %T'; // see http://php.net/manual/en/function.strftime.php for more example
// -----------------------------------------------------------------------------------------------
// You should not touch below (or at your own risks !)
// Optionnal config file.
if (file_exists($GLOBALS['config']['CONFIG_FILE'])) {
    require $GLOBALS['config']['CONFIG_FILE'];  // Read login/password hash into $GLOBALS.
}

if (is_file($GLOBALS['config']['DATADIR'].'/options.php')) {
    require $GLOBALS['config']['DATADIR'].'/options.php';
}

define('myShaarli_version', '1.1.5');
define('PHPPREFIX', '<?php /* '); // Prefix to encapsulate data in php code.
define('PHPSUFFIX', ' */ ?>'); // Suffix to encapsulate data in php code.
// http://server.com/x/shaarli --> /shaarli/
define('WEB_PATH', substr($_SERVER['REQUEST_URI'], 0, 1 + strrpos($_SERVER['REQUEST_URI'], '/', 0)));

// Force cookie path (but do not change lifetime)
$cookie = session_get_cookie_params();
$cookiedir = ''; if (dirname($_SERVER['SCRIPT_NAME']) != '/') {
     $cookiedir = dirname($_SERVER['SCRIPT_NAME']).'/';
 }
session_set_cookie_params($cookie['lifetime'], $cookiedir, $_SERVER['HTTP_HOST']); // Set default cookie expiration and path.

// Set session parameters on server side.
define('INACTIVITY_TIMEOUT', 3600); // (in seconds). If the user does not access any page within this time, his/her session is considered expired.
ini_set('session.use_cookies', 1);       // Use cookies to store session.
ini_set('session.use_only_cookies', 1);  // Force cookies for session (phpsessionID forbidden in URL)
ini_set('session.use_trans_sid', false); // Prevent php to use sessionID in URL if cookies are disabled.
session_name('shaarli');
if (session_id() == '') {
    session_start();
}  // Start session if needed (Some server auto-start sessions).

// PHP Settings
ini_set('max_input_time', '60');  // High execution time in case of problematic imports/exports.
ini_set('memory_limit', '128M');  // Try to set max upload file size and read (May not work on some hosts).
ini_set('post_max_size', '16M');
ini_set('upload_max_filesize', '16M');
checkphpversion();
error_reporting(E_ALL ^ E_WARNING);  // See all error except warnings.
//error_reporting(-1); // See all errors (for debugging only)
if ($GLOBALS['config']['ENABLE_MARKDOWN'] === true) {
    include 'inc/Parsedown.php';
}
include 'inc/rain.tpl.class.php'; //include Rain TPL
raintpl::$tpl_dir = 'tpl/'.$GLOBALS['config']['THEME'].'/'; // template directory
if (!is_dir('tmp')) {
    mkdir('tmp', 0705);
    chmod('tmp', 0705);
}
raintpl::$cache_dir = 'tmp/'; // cache directory

ob_start();  // Output buffering for the page cache.

// In case stupid admin has left magic_quotes enabled in php.ini:
if (get_magic_quotes_gpc()) {
    function stripslashes_deep($value)
    {
        $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value);

        return $value;
    }
    $_POST = array_map('stripslashes_deep', $_POST);
    $_GET = array_map('stripslashes_deep', $_GET);
    $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
}

// Prevent caching on client side or proxy: (yes, it's ugly)
header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
header('Cache-Control: no-store, no-cache, must-revalidate');
header('Cache-Control: post-check=0, pre-check=0', false);
header('Pragma: no-cache');

// Directories creations (Note that your web host may require differents rights than 705.)
if (!is_writable(realpath(dirname(__FILE__)))) {
    die('<pre>ERROR: Shaarli does not have the right to write in its own directory ('.realpath(dirname(__FILE__)).').</pre>');
}
if (!is_dir($GLOBALS['config']['DATADIR'])) {
    mkdir($GLOBALS['config']['DATADIR'], 0705);
    chmod($GLOBALS['config']['DATADIR'], 0705);
}
if (!is_dir('tmp')) {
    mkdir('tmp', 0705);
    chmod('tmp', 0705);
} // For RainTPL temporary files.
if (!is_file($GLOBALS['config']['DATADIR'].'/.htaccess')) {
    file_put_contents($GLOBALS['config']['DATADIR'].'/.htaccess', "Allow from none\nDeny from all\n");
} // Protect data files.
// Second check to see if Shaarli can write in its directory, because on some hosts is_writable() is not reliable.
if (!is_file($GLOBALS['config']['DATADIR'].'/.htaccess')) {
    die('<pre>ERROR: Shaarli does not have the right to write in its data directory ('.realpath($GLOBALS['config']['DATADIR']).').</pre>');
}
if ($GLOBALS['config']['ENABLE_LOCALCACHE']) {
    if (!is_dir($GLOBALS['config']['CACHEDIR'])) {
        mkdir($GLOBALS['config']['CACHEDIR'], 0705);
        chmod($GLOBALS['config']['CACHEDIR'], 0705);
    }
    if (!is_file($GLOBALS['config']['CACHEDIR'].'/.htaccess')) {
        file_put_contents($GLOBALS['config']['CACHEDIR'].'/.htaccess', "Allow from none\nDeny from all\n");
    } // Protect data files.
}

// Handling of old config file which do not have the new parameters.
if (empty($GLOBALS['title'])) {
    $GLOBALS['title'] = 'Shared links on '.htmlspecialchars(indexUrl());
}
if (empty($GLOBALS['timezone'])) {
    $GLOBALS['timezone'] = date_default_timezone_get();
}
if (empty($GLOBALS['redirector'])) {
    $GLOBALS['redirector'] = '';
}
if (empty($GLOBALS['disablesessionprotection'])) {
    $GLOBALS['disablesessionprotection'] = false;
}
if (empty($GLOBALS['disablejquery'])) {
    $GLOBALS['disablejquery'] = false;
}
if (empty($GLOBALS['privateLinkByDefault'])) {
    $GLOBALS['privateLinkByDefault'] = false;
}
if (empty($GLOBALS['titleLink'])) {
    $GLOBALS['titleLink'] = '?';
}

// Run config screen if first run:
if (!is_file($GLOBALS['config']['CONFIG_FILE'])) {
    install();
}

// a token depending of deployment salt, user password, and the current ip
define('STAY_SIGNED_IN_TOKEN', sha1($GLOBALS['hash'].$_SERVER['REMOTE_ADDR'].$GLOBALS['salt']));

autoLocale(); // Sniff browser language and set date format accordingly.
header('Content-Type: text/html; charset=utf-8'); // We use UTF-8 for proper international characters handling.

// Check php version
function checkphpversion()
{
    if (version_compare(PHP_VERSION, '5.1.0') < 0) {
        header('Content-Type: text/plain; charset=utf-8');
        echo 'Your server supports php '.PHP_VERSION.'. Shaarli requires at least php 5.1.0, and thus cannot run. Sorry.';
        exit;
    }
}

// Checks if an update is available for Shaarli.
// (at most once a day, and only for registered user.)
// Output: '' = no new version.
//         other= the available version.
function checkUpdate()
{
    if (!isLoggedIn()) {
        return false; // Do not check versions for visitors.
    }
    if (empty($GLOBALS['config']['ENABLE_UPDATECHECK'])) {
        return false; // Do not check if the user doesn't want to.
    }
    // Get latest version number at most once a day.
    if (!is_file($GLOBALS['config']['UPDATECHECK_FILENAME']) || (filemtime($GLOBALS['config']['UPDATECHECK_FILENAME']) < time() - ($GLOBALS['config']['UPDATECHECK_INTERVAL']))) {
        $version = myShaarli_version;
        list($httpstatus, $headers, $data) = getHTTP($GLOBALS['config']['UPDATECHECK_URL'], 2);
        if (strpos($httpstatus, '200 OK') !== false || strpos($httpstatus, '301') !== false) {
            $version = $data;
        }
          // If failed, nevermind. We don't want to bother the user with that.
          file_put_contents($GLOBALS['config']['UPDATECHECK_FILENAME'], $version); // touch file date
    }
    // Compare versions:
    $newestversion = trim(file_get_contents($GLOBALS['config']['UPDATECHECK_FILENAME']));
    if (version_compare(strtolower(myShaarli_version), strtolower($newestversion)) == 0) {
        return false;
    }
    if (version_compare(strtolower(myShaarli_version), strtolower($newestversion)) == 1) {
        return 'You have future version ?!';
    }
    if (version_compare(strtolower(myShaarli_version), strtolower($newestversion)) == -1) {
        return 'New update of myShaarli available.';
    }
    return false;
}

// -----------------------------------------------------------------------------------------------
// Simple cache system (mainly for the RSS/ATOM feeds).

class pageCache
{
    private $url; // Full URL of the page to cache (typically the value returned by pageUrl())
    private $shouldBeCached; // boolean: Should this url be cached ?
    private $filename; // Name of the cache file for this url

    /*
         $url = url (typically the value returned by pageUrl())
         $shouldBeCached = boolean. If false, the cache will be disabled.
    */
    public function __construct($url, $shouldBeCached)
    {
        $this->url = $url;
        $this->filename = $GLOBALS['config']['PAGECACHE'].'/'.sha1($url).'.cache';
        $this->shouldBeCached = $shouldBeCached;
    }

    // If the page should be cached and a cached version exists,
    // returns the cached version (otherwise, return null).
    public function cachedVersion()
    {
        if (!$this->shouldBeCached) {
            return;
        }
        if (is_file($this->filename)) {
            return file_get_contents($this->filename);
            exit;
        }

        return;
    }

    // Put a page in the cache.
    public function cache($page)
    {
        if (!$this->shouldBeCached) {
            return;
        }
        if (!is_dir($GLOBALS['config']['PAGECACHE'])) {
            mkdir($GLOBALS['config']['PAGECACHE'], 0705);
            chmod($GLOBALS['config']['PAGECACHE'], 0705);
        }
        file_put_contents($this->filename, $page);
    }

    // Purge the whole cache.
    // (call with pageCache::purgeCache())
    public static function purgeCache()
    {
        if (is_dir($GLOBALS['config']['PAGECACHE'])) {
            $handler = opendir($GLOBALS['config']['PAGECACHE']);
            if ($handler !== false) {
                while (($filename = readdir($handler)) !== false) {
                    if (endsWith($filename, '.cache')) {
                        unlink($GLOBALS['config']['PAGECACHE'].'/'.$filename);
                    }
                }
                closedir($handler);
            }
        }
    }
}

// -----------------------------------------------------------------------------------------------
// Log to text file
function logm($message)
{
    $t = strval(date('Y/m/d H:i:s')).' - '.$_SERVER['REMOTE_ADDR'].' - '.strval($message)."\n";
    file_put_contents($GLOBALS['config']['DATADIR'].'/log.txt', $t, FILE_APPEND);
}

// Same as nl2br(), but escapes < and >
function nl2br_escaped($html)
{
    return str_replace('>', '&gt;', str_replace('<', '&lt;', nl2br($html)));
}

/* Returns the small hash of a string, using RFC 4648 base64url format
   eg. smallHash('20111006_131924') --> yZH23w
   Small hashes:
     - are unique (well, as unique as crc32, at last)
     - are always 6 characters long.
     - only use the following characters: a-z A-Z 0-9 - _ @
     - are NOT cryptographically secure (they CAN be forged)
   In Shaarli, they are used as a tinyurl-like link to individual entries.
*/
function smallHash($text)
{
    $t = rtrim(base64_encode(hash('crc32', $text, true)), '=');

    return strtr($t, '+/', '-_');
}

// In a string, converts urls to clickable links.
// Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
function text2clickable($url)
{
    $redir = empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'];

    return preg_replace('!(((?:https?|ftp|file)://|apt:|magnet:)\S+[[:alnum:]]/?)!si', '<a href="'.$redir.'$1" rel="nofollow">$1</a>', $url);
}

// This function inserts &nbsp; where relevant so that multiple spaces are properly displayed in HTML
// even in the absence of <pre>  (This is used in description to keep text formatting)
function keepMultipleSpaces($text)
{
    return str_replace('  ', ' &nbsp;', $text);
}
// ------------------------------------------------------------------------------------------
// Sniff browser language to display dates in the right format automatically.
// (Note that is may not work on your server if the corresponding local is not installed.)
function autoLocale()
{
    $attempts = array('en_US'); // Default if browser does not send HTTP_ACCEPT_LANGUAGE
    if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
        // e.g. "fr,fr-fr;q=0.8,en;q=0.5,en-us;q=0.3"
   // (It's a bit crude, but it works very well. Preferred language is always presented first.)
        if (preg_match('/([a-z]{2})-?([a-z]{2})?/i', $_SERVER['HTTP_ACCEPT_LANGUAGE'], $matches)) {
            $loc = $matches[1].(!empty($matches[2]) ? '_'.strtoupper($matches[2]) : '');
            $attempts = array($loc.'.UTF-8', $loc, str_replace('_', '-', $loc).'.UTF-8', str_replace('_', '-', $loc),
                $loc.'_'.strtoupper($loc).'.UTF-8', $loc.'_'.strtoupper($loc),
                $loc.'_'.$loc.'.UTF-8', $loc.'_'.$loc, $loc.'-'.strtoupper($loc).'.UTF-8',
                $loc.'-'.strtoupper($loc), $loc.'-'.$loc.'.UTF-8', $loc.'-'.$loc, );
        }
    }
    setlocale(LC_TIME, $attempts);  // LC_TIME = Set local for date/time format only.
}

// ------------------------------------------------------------------------------------------
// PubSubHubbub protocol support (if enabled)  [UNTESTED]
// (Source: http://aldarone.fr/les-flux-rss-shaarli-et-pubsubhubbub/ )
if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) {
    include './publisher.php';
}
function pubsubhub()
{
    if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) {
        $p = new Publisher($GLOBALS['config']['PUBSUBHUB_URL']);
        $topic_url = array(
                       indexUrl().'?do=atom',
                       indexUrl().'?do=rss',
                    );
        $p->publish_update($topic_url);
    }
}

// ------------------------------------------------------------------------------------------
// Session management

// Returns the IP address of the client (Used to prevent session cookie hijacking.)
function allIPs()
{
    $ip = $_SERVER['REMOTE_ADDR'];
    // Then we use more HTTP headers to prevent session hijacking from users behind the same proxy.
    if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ip = $ip.'_'.$_SERVER['HTTP_X_FORWARDED_FOR'];
    }
    if (isset($_SERVER['HTTP_CLIENT_IP'])) {
        $ip = $ip.'_'.$_SERVER['HTTP_CLIENT_IP'];
    }

    return $ip;
}

function fillSessionInfo()
{
    $_SESSION['uid'] = sha1(uniqid('', true).'_'.mt_rand()); // generate unique random number (different than phpsessionid)
    $_SESSION['ip'] = allIPs();                // We store IP address(es) of the client to make sure session is not hijacked.
    $_SESSION['username'] = $GLOBALS['login'];
    $_SESSION['expires_on'] = time() + INACTIVITY_TIMEOUT;  // Set session expiration.
}

// Check that user/password is correct.
function check_auth($login, $password)
{
    $hash = sha1($password.$login.$GLOBALS['salt']);
    if ($login == $GLOBALS['login'] && $hash == $GLOBALS['hash']) {   // Login/password is correct.
        fillSessionInfo();
        logm('Login successful');

        return true;
    }
    logm('Login failed for user '.$login);

    return false;
}

// Returns true if the user is logged in.
function isLoggedIn()
{
    if ($GLOBALS['config']['OPEN_SHAARLI']) {
        return true;
    }

    if (!isset($GLOBALS['login'])) {
        return false;
    }  // Shaarli is not configured yet.

    if (@$_COOKIE['shaarli_staySignedIn'] === STAY_SIGNED_IN_TOKEN) {
        fillSessionInfo();

        return true;
    }
    // If session does not exist on server side, or IP address has changed, or session has expired, logout.
    if (empty($_SESSION['uid']) || ($GLOBALS['disablesessionprotection'] == false && $_SESSION['ip'] != allIPs()) || time() >= $_SESSION['expires_on']) {
        logout();

        return false;
    }
    if (!empty($_SESSION['longlastingsession'])) {
        $_SESSION['expires_on'] = time() + $_SESSION['longlastingsession'];
    } // In case of "Stay signed in" checked.
    else {
        $_SESSION['expires_on'] = time() + INACTIVITY_TIMEOUT;
    } // Standard session expiration date.

    return true;
}

// Force logout.
function logout()
{
    if (isset($_SESSION)) {
        unset($_SESSION['uid'], $_SESSION['ip'], $_SESSION['username'], $_SESSION['privateonly']);
    }
    setcookie('shaarli_staySignedIn', false, 0, WEB_PATH);
}

// ------------------------------------------------------------------------------------------
// Brute force protection system
// Several consecutive failed logins will ban the IP address for 30 minutes.
if (!is_file($GLOBALS['config']['IPBANS_FILENAME'])) {
    file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export(array('FAILURES' => array(), 'BANS' => array()), true).";\n?>");
}
include $GLOBALS['config']['IPBANS_FILENAME'];
// Signal a failed login. Will ban the IP if too many failures:
function ban_loginFailed()
{
    $ip = $_SERVER['REMOTE_ADDR'];
    $gb = $GLOBALS['IPBANS'];
    if (!isset($gb['FAILURES'][$ip])) {
        $gb['FAILURES'][$ip] = 0;
    }
    ++$gb['FAILURES'][$ip];
    if ($gb['FAILURES'][$ip] > ($GLOBALS['config']['BAN_AFTER'] - 1)) {
        $gb['BANS'][$ip] = time() + $GLOBALS['config']['BAN_DURATION'];
        logm('IP address banned from login');
    }
    $GLOBALS['IPBANS'] = $gb;
    file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");
}

// Signals a successful login. Resets failed login counter.
function ban_loginOk()
{
    $ip = $_SERVER['REMOTE_ADDR'];
    $gb = $GLOBALS['IPBANS'];
    unset($gb['FAILURES'][$ip]);
    unset($gb['BANS'][$ip]);
    $GLOBALS['IPBANS'] = $gb;
    file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");
}

// Checks if the user CAN login. If 'true', the user can try to login.
function ban_canLogin()
{
    $ip = $_SERVER['REMOTE_ADDR'];
    $gb = $GLOBALS['IPBANS'];
    if (isset($gb['BANS'][$ip])) {
        // User is banned. Check if the ban has expired:
        if ($gb['BANS'][$ip] <= time()) {   // Ban expired, user can try to login again.
            logm('Ban lifted.');
            unset($gb['FAILURES'][$ip]);
            unset($gb['BANS'][$ip]);
            file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");

            return true; // Ban has expired, user can login.
        }

        return false; // User is banned.
    }

    return true; // User is not banned.
}

// ------------------------------------------------------------------------------------------
// Process login form: Check if login/password is correct.
if (isset($_POST['login'])) {
    if (!ban_canLogin()) {
        die('I said: NO. You are banned for the moment. Go away.');
    }
    if (isset($_POST['password']) && tokenOk($_POST['token']) && (check_auth($_POST['login'], $_POST['password']))) {   // Login/password is ok.
        ban_loginOk();
        // If user wants to keep the session cookie even after the browser closes:
        if (!empty($_POST['longlastingsession'])) {
            setcookie('shaarli_staySignedIn', STAY_SIGNED_IN_TOKEN, time() + 31536000, WEB_PATH);
            $_SESSION['longlastingsession'] = 31536000;  // (31536000 seconds = 1 year)
            $_SESSION['expires_on'] = time() + $_SESSION['longlastingsession'];  // Set session expiration on server-side.

            $cookiedir = '';
            if (dirname($_SERVER['SCRIPT_NAME']) != '/') {
                $cookiedir = dirname($_SERVER['SCRIPT_NAME']).'/';
            }
            session_set_cookie_params($_SESSION['longlastingsession'], $cookiedir, $_SERVER['HTTP_HOST']); // Set session cookie expiration on client side
            // Note: Never forget the trailing slash on the cookie path !
            session_regenerate_id(true);  // Send cookie with new expiration date to browser.
        } else {
            // Standard session expiration (=when browser closes)

            $cookiedir = '';
            if (dirname($_SERVER['SCRIPT_NAME']) != '/') {
                $cookiedir = dirname($_SERVER['SCRIPT_NAME']).'/';
            }
            session_set_cookie_params(0, $cookiedir, $_SERVER['HTTP_HOST']); // 0 means "When browser closes"
            session_regenerate_id(true);
        }
        // Optional redirect after login:
        if (isset($_GET['post'])) {
            header('Location: ?post='.urlencode($_GET['post']).(!empty($_GET['title']) ? '&title='.urlencode($_GET['title']) : '').(!empty($_GET['source']) ? '&source='.urlencode($_GET['source']) : ''));
            exit;
        }
        if (isset($_POST['returnurl'])) {
            if (endsWith($_POST['returnurl'], '?do=login')) {
                header('Location: ?');
                exit;
            } // Prevent loops over login screen.
            header('Location: '.$_POST['returnurl']);
            exit;
        }
        header('Location: ?');
        exit;
    } else {
        ban_loginFailed();
        $redir = '';
        if (isset($_GET['post'])) {
            $redir = '&post='.urlencode($_GET['post']).(!empty($_GET['title']) ? '&title='.urlencode($_GET['title']) : '').(!empty($_GET['source']) ? '&source='.urlencode($_GET['source']) : '');
        }
        echo '<script>alert("Wrong login/password.");document.location=\'?do=login'.$redir.'\';</script>'; // Redirect to login screen.
        exit;
    }
}

// ------------------------------------------------------------------------------------------
// Misc utility functions:

// Try to get just domain for @via
function getJustDomain($url)
{
    $parts = parse_url($url);

    return trim($parts['host']);
}

// Returns the server URL (including port and http/https), without path.
// eg. "http://myserver.com:8080"
// You can append $_SERVER['SCRIPT_NAME'] to get the current script URL.
function serverUrl()
{
    $https = (!empty($_SERVER['HTTPS']) && (strtolower($_SERVER['HTTPS']) == 'on')) || $_SERVER['SERVER_PORT'] == '443'; // HTTPS detection.
    $serverport = ($_SERVER['SERVER_PORT'] == '80' || ($https && $_SERVER['SERVER_PORT'] == '443') ? '' : ':'.$_SERVER['SERVER_PORT']);

    return 'http'.($https ? 's' : '').'://'.$_SERVER['HTTP_HOST'].$serverport;
}

// Returns the absolute URL of current script, without the query.
// (eg. http://sebsauvage.net/links/)
function indexUrl()
{
    $scriptname = $_SERVER['SCRIPT_NAME'];
    // If the script is named 'index.php', we remove it (for better looking URLs,
    // eg. http://mysite.com/shaarli/?abcde instead of http://mysite.com/shaarli/index.php?abcde)
    if (endswith($scriptname, 'index.php')) {
        $scriptname = substr($scriptname, 0, strlen($scriptname) - 9);
    }

    return serverUrl().$scriptname;
}

// Returns the absolute URL of current script, WITH the query.
// (eg. http://sebsauvage.net/links/?toto=titi&spamspamspam=humbug)
function pageUrl()
{
    return indexUrl().(!empty($_SERVER['QUERY_STRING']) ? '?'.$_SERVER['QUERY_STRING'] : '');
}

// Convert post_max_size/upload_max_filesize (eg.'16M') parameters to bytes.
function return_bytes($val)
{
    $val = trim($val);
    $last = strtolower($val[strlen($val) - 1]);
    switch ($last) {
        case 'g': $val *= 1024;
        case 'm': $val *= 1024;
        case 'k': $val *= 1024;
    }

    return $val;
}

// Try to determine max file size for uploads (POST).
// Returns an integer (in bytes)
function getMaxFileSize()
{
    $size1 = return_bytes(ini_get('post_max_size'));
    $size2 = return_bytes(ini_get('upload_max_filesize'));
    // Return the smaller of two:
    $maxsize = min($size1, $size2);
    // FIXME: Then convert back to readable notations ? (eg. 2M instead of 2000000)
    return $maxsize;
}

// Tells if a string start with a substring or not.
function startsWith($haystack, $needle, $case = true)
{
    if ($case) {
        return strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0;
    }

    return strcasecmp(substr($haystack, 0, strlen($needle)), $needle) === 0;
}

// Tells if a string ends with a substring or not.
function endsWith($haystack, $needle, $case = true)
{
    if ($case) {
        return strcmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0;
    }

    return strcasecmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0;
}

/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a timestamp (Unix epoch)
    (used to build the ADD_DATE attribute in Netscape-bookmarks file)
    PS: I could have used strptime(), but it does not exist on Windows. I'm too kind. */
function linkdate2timestamp($linkdate)
{
    $Y = $M = $D = $h = $m = $s = 0;
    sscanf($linkdate, '%4d%2d%2d_%2d%2d%2d', $Y, $M, $D, $h, $m, $s);

    return mktime($h, $m, $s, $M, $D, $Y);
}

/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a RFC822 date.
    (used to build the pubDate attribute in RSS feed.)  */
function linkdate2rfc822($linkdate)
{
    return date('r', linkdate2timestamp($linkdate)); // 'r' is for RFC822 date format.
}

/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a ISO 8601 date.
    (used to build the updated tags in ATOM feed.)  */
function linkdate2iso8601($linkdate)
{
    return date('c', linkdate2timestamp($linkdate)); // 'c' is for ISO 8601 date format.
}

/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a localized date format.
    (used to display link date on screen)
    The date format is automatically chosen according to locale/languages sniffed from browser headers (see autoLocale()). */
function linkdate2locale($linkdate)
{
    if (empty($GLOBALS['config']['DATE_FORMAT'])) {
        $GLOBALS['config']['DATE_FORMAT'] = '%c';
    }

    return strftime($GLOBALS['config']['DATE_FORMAT'], linkdate2timestamp($linkdate)); // %c is for automatic date format according to locale.
    // Note that if you use a local which is not installed on your webserver,
    // the date will not be displayed in the chosen locale, but probably in US notation.
}

// Parse HTTP response headers and return an associative array.
function http_parse_headers_shaarli($headers)
{
    $res = array();
    foreach ($headers as $header) {
        $i = strpos($header, ': ');
        if ($i !== false) {
            $key = substr($header, 0, $i);
            $value = substr($header, $i + 2, strlen($header) - $i - 2);
            $res[$key] = $value;
        }
    }

    return $res;
}

/* GET an URL.
   Input: $url : url to get (http://...)
          $timeout : Network timeout (will wait this many seconds for an anwser before giving up).
   Output: An array.  [0] = HTTP status message (eg. "HTTP/1.1 200 OK") or error message
                      [1] = associative array containing HTTP response headers (eg. echo getHTTP($url)[1]['Content-Type'])
                      [2] = data
    Example: list($httpstatus,$headers,$data) = getHTTP('http://sebauvage.net/');
             if (strpos($httpstatus,'200 OK')!==false)
                 echo 'Data type: '.htmlspecialchars($headers['Content-Type']);
             else
                 echo 'There was an error: '.htmlspecialchars($httpstatus)
*/
function getHTTP($url, $timeout = 30)
{
    try {
        $options = array('http' => array('method' => 'GET', 'timeout' => $timeout, 'user_agent' => 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:23.0) Gecko/20100101 Firefox/23.0')); // Force network timeout
        $context = stream_context_create($options);
        $data = file_get_contents($url, false, $context, -1, 4000000); // We download at most 4 Mb from source.
        if (!$data) {
            return array('HTTP Error', array(), '');
        }
        $httpStatus = $http_response_header[0]; // eg. "HTTP/1.1 200 OK"
        $responseHeaders = http_parse_headers_shaarli($http_response_header);

        return array($httpStatus, $responseHeaders, $data);
    } catch (Exception $e) {
        // getHTTP *can* fail silentely (we don't care if the title cannot be fetched)

        return array($e->getMessage(), '', '');
    }
}

// Extract title from an HTML document.
// (Returns an empty string if not found.)
function html_extract_title($html)
{
    return preg_match('!<title>(.*?)</title>!is', $html, $matches) ? trim(str_replace("\n", ' ', $matches[1])) : '';
}

// ------------------------------------------------------------------------------------------
// Token management for XSRF protection
// Token should be used in any form which acts on data (create,update,delete,import...).
if (!isset($_SESSION['tokens'])) {
    $_SESSION['tokens'] = array();
}  // Token are attached to the session.

// Returns a token.
function getToken()
{
    $rnd = sha1(uniqid('', true).'_'.mt_rand().$GLOBALS['salt']);  // We generate a random string.
    $_SESSION['tokens'][$rnd] = 1;  // Store it on the server side.
    return $rnd;
}

// Tells if a token is ok. Using this function will destroy the token.
// true=token is ok.
function tokenOk($token)
{
    if (isset($_SESSION['tokens'][$token])) {
        unset($_SESSION['tokens'][$token]); // Token is used: destroy it.
        return true; // Token is ok.
    }

    return false; // Wrong token, or already used.
}

// ------------------------------------------------------------------------------------------
/* This class is in charge of building the final page.
   (This is basically a wrapper around RainTPL which pre-fills some fields.)
   p = new pageBuilder;
   p.assign('myfield','myvalue');
   p.renderPage('mytemplate');

*/
class pageBuilder
{
    private $tpl; // RainTPL template

    public function __construct()
    {
        $this->tpl = false;
    }

    private function initialize()
    {
        $this->tpl = new RainTPL();
        $this->tpl->assign('theme', $GLOBALS['config']['THEME']);
        $this->tpl->assign('newversion', checkUpdate());
        $this->tpl->assign('feedurl', htmlspecialchars(indexUrl()));
        $searchcrits = ''; // Search criteria
        if (!empty($_GET['searchtags'])) {
            $searchcrits .= '&searchtags='.urlencode($_GET['searchtags']);
        } elseif (!empty($_GET['searchterm'])) {
            $searchcrits .= '&searchterm='.urlencode($_GET['searchterm']);
        }
        $this->tpl->assign('searchcrits', $searchcrits);
        $this->tpl->assign('source', indexUrl());
        $this->tpl->assign('version', myShaarli_version);
        $this->tpl->assign('scripturl', indexUrl());
        $this->tpl->assign('pagetitle', 'Shaarli');
        $this->tpl->assign('privateonly', !empty($_SESSION['privateonly'])); // Show only private links ?
        if (!empty($GLOBALS['title'])) {
            $this->tpl->assign('pagetitle', $GLOBALS['title']);
        }
        if (!empty($GLOBALS['titleLink'])) {
            $this->tpl->assign('titleLink', $GLOBALS['titleLink']);
        }
        if (!empty($GLOBALS['pagetitle'])) {
            $this->tpl->assign('pagetitle', $GLOBALS['pagetitle']);
        }
        $this->tpl->assign('shaarlititle', empty($GLOBALS['title']) ? 'Shaarli' : $GLOBALS['title']);

        return;
    }

    // The following assign() method is basically the same as RainTPL (except that it's lazy)
    public function assign($what, $where)
    {
        if ($this->tpl === false) {
            $this->initialize();
        } // Lazy initialization
        $this->tpl->assign($what, $where);
    }

    // Render a specific page (using a template).
    // eg. pb.renderPage('picwall')
    public function renderPage($page)
    {
        if ($this->tpl === false) {
            $this->initialize();
        } // Lazy initialization
          $this->tpl->draw($page);
    }
}

// ------------------------------------------------------------------------------------------
/* Data storage for links.
   This object behaves like an associative array.
   Example:
      $mylinks = new linkdb();
      echo $mylinks['20110826_161819']['title'];
      foreach($mylinks as $link)
         echo $link['title'].' at url '.$link['url'].' ; description:'.$link['description'];

   Available keys:
       title : Title of the link
       url : URL of the link. Can be absolute or relative. Relative URLs are permalinks (eg.'?m-ukcw')
       description : description of the entry
       private : Is this link private ? 0=no, other value=yes
       linkdate : date of the creation of this entry, in the form YYYYMMDD_HHMMSS (eg.'20110914_192317')
       tags : tags attached to this entry (separated by spaces)

   We implement 3 interfaces:
     - ArrayAccess so that this object behaves like an associative array.
     - Iterator so that this object can be used in foreach() loops.
     - Countable interface so that we can do a count() on this object.
*/
class linkdb implements Iterator, Countable, ArrayAccess
{
    private $links; // List of links (associative array. Key=linkdate (eg. "20110823_124546"), value= associative array (keys:title,description...)
    private $urls;  // List of all recorded URLs (key=url, value=linkdate) for fast reserve search (url-->linkdate)
    private $keys;  // List of linkdate keys (for the Iterator interface implementation)
    private $position; // Position in the $this->keys array. (for the Iterator interface implementation.)
    private $loggedin; // Is the used logged in ? (used to filter private links)

    // Constructor:
    public function __construct($isLoggedIn)
    // Input : $isLoggedIn : is the used logged in ?
    {
        $this->loggedin = $isLoggedIn;
        $this->checkdb(); // Make sure data file exists.
        $this->readdb();  // Then read it.
    }

    // ---- Countable interface implementation
    public function count()
    {
        return count($this->links);
    }

    // ---- ArrayAccess interface implementation
    public function offsetSet($offset, $value)
    {
        if (!$this->loggedin) {
            die('You are not authorized to add a link.');
        }
        if (empty($value['linkdate']) || empty($value['url'])) {
            die('Internal Error: A link should always have a linkdate and url.');
        }
        if (empty($offset)) {
            die('You must specify a key.');
        }
        $this->links[$offset] = $value;
        $this->urls[$value['url']] = $offset;
    }
    public function offsetExists($offset)
    {
        return array_key_exists($offset, $this->links);
    }
    public function offsetUnset($offset)
    {
        if (!$this->loggedin) {
            die('You are not authorized to delete a link.');
        }
        $url = $this->links[$offset]['url'];
        unset($this->urls[$url]);
        unset($this->links[$offset]);
    }
    public function offsetGet($offset)
    {
        return isset($this->links[$offset]) ? $this->links[$offset] : null;
    }

    // ---- Iterator interface implementation
    public function rewind()
    {
        $this->keys = array_keys($this->links);
        rsort($this->keys);
        $this->position = 0;
    } // Start over for iteration, ordered by date (latest first).
    public function key()
    {
        return $this->keys[$this->position];
    } // current key
    public function current()
    {
        return $this->links[$this->keys[$this->position]];
    } // current value
    public function next()
    {
        ++$this->position;
    } // go to next item
    public function valid()
    {
        return isset($this->keys[$this->position]);
    }    // Check if current position is valid.

    // ---- Misc methods
    private function checkdb() // Check if db directory and file exists.
    {
        if (!file_exists($GLOBALS['config']['DATASTORE'])) {
            // Create a dummy database for example.

             $this->links = array();
            $link = array('title' => 'Shaarli - sebsauvage.net', 'url' => 'http://sebsauvage.net/wiki/doku.php?id=php:shaarli', 'description' => 'Welcome to Shaarli ! This is a bookmark. To edit or delete me, you must first login.', 'private' => 0, 'linkdate' => '20110914_190000', 'tags' => 'opensource software');
            $this->links[$link['linkdate']] = $link;
            $link = array('title' => 'My secret stuff... - Pastebin.com', 'url' => 'http://sebsauvage.net/paste/?8434b27936c09649#bR7XsXhoTiLcqCpQbmOpBi3rq2zzQUC5hBI7ZT1O3x8=', 'description' => 'SShhhh!!  I\'m a private link only YOU can see. You can delete me too.', 'private' => 1, 'linkdate' => '20110914_074522', 'tags' => 'secretstuff');
            $this->links[$link['linkdate']] = $link;
            file_put_contents($GLOBALS['config']['DATASTORE'], PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX); // Write database to disk
        }
    }

    // Read database from disk to memory
    private function readdb()
    {
        // Read data
        $this->links = (file_exists($GLOBALS['config']['DATASTORE']) ? unserialize(gzinflate(base64_decode(substr(file_get_contents($GLOBALS['config']['DATASTORE']), strlen(PHPPREFIX), -strlen(PHPSUFFIX))))) : array());
        // Note that gzinflate is faster than gzuncompress. See: http://www.php.net/manual/en/function.gzdeflate.php#96439

        // If user is not logged in, filter private links.
        if (!$this->loggedin) {
            $toremove = array();
            foreach ($this->links as $link) {
                if ($link['private'] != 0) {
                    $toremove[] = $link['linkdate'];
                }
            }
            foreach ($toremove as $linkdate) {
                unset($this->links[$linkdate]);
            }
        }

        // Keep the list of the mapping URLs-->linkdate up-to-date.
        $this->urls = array();
        foreach ($this->links as $link) {
            $this->urls[$link['url']] = $link['linkdate'];
        }
    }

    // Save database from memory to disk.
    public function savedb()
    {
        if (!$this->loggedin) {
            die('You are not authorized to change the database.');
        }
        file_put_contents($GLOBALS['config']['DATASTORE'], PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX);
        invalidateCaches();
    }

    // Returns the link for a given URL (if it exists). false it does not exist.
    public function getLinkFromUrl($url)
    {
        if (isset($this->urls[$url])) {
            return $this->links[$this->urls[$url]];
        }

        return false;
    }

    // Case insentitive search among links (in url, title and description). Returns filtered list of links.
    // eg. print_r($mydb->filterFulltext('hollandais'));
    public function filterFulltext($searchterms)
    {
        // FIXME: explode(' ',$searchterms) and perform a AND search.
        // FIXME: accept double-quotes to search for a string "as is" ?
        $filtered = array();
        $s = strtolower($searchterms);
        foreach ($this->links as $l) {
            $found = (strpos(strtolower($l['title']), $s) !== false)
                   || (strpos(strtolower($l['description']), $s) !== false)
                   || (strpos(strtolower($l['url']), $s) !== false)
                   || (strpos(strtolower($l['tags']), $s) !== false)
                   || (!empty($l['via']) && (strpos(strtolower($l['via']), $s) !== false));
            if ($found) {
                $filtered[$l['linkdate']] = $l;
            }
        }
        krsort($filtered);

        return $filtered;
    }

    // Filter by tag.
    // You can specify one or more tags (tags can be separated by space or comma).
    // eg. print_r($mydb->filterTags('linux programming'));
    public function filterTags($tags, $casesensitive = false)
    {
        $t = str_replace(',', ' ', ($casesensitive ? $tags : strtolower($tags)));
        $searchtags = explode(' ', $t);
        $filtered = array();
        foreach ($this->links as $l) {
            $linktags = explode(' ', ($casesensitive ? $l['tags'] : strtolower($l['tags'])));
            if (count(array_intersect($linktags, $searchtags)) == count($searchtags)) {
                $filtered[$l['linkdate']] = $l;
            }
        }
        krsort($filtered);

        return $filtered;
    }

    // Filter by day. Day must be in the form 'YYYYMMDD' (eg. '20120125')
    // Sort order is: older articles first.
    // eg. print_r($mydb->filterDay('20120125'));
    public function filterDay($day)
    {
        $filtered = array();
        foreach ($this->links as $l) {
            if (startsWith($l['linkdate'], $day)) {
                $filtered[$l['linkdate']] = $l;
            }
        }
        ksort($filtered);

        return $filtered;
    }
    // Filter by smallHash.
    // Only 1 article is returned.
    public function filterSmallHash($smallHash)
    {
        $filtered = array();
        foreach ($this->links as $l) {
            if ($smallHash == smallHash($l['linkdate'])) {
                // Yes, this is ugly and slow

                $filtered[$l['linkdate']] = $l;

                return $filtered;
            }
        }

        return $filtered;
    }

    // Returns the list of all tags
    // Output: associative array key=tags, value=0
    public function allTags()
    {
        $tags = array();
        foreach ($this->links as $link) {
            foreach (explode(' ', $link['tags']) as $tag) {
                if (!empty($tag)) {
                    $tags[$tag] = (empty($tags[$tag]) ? 1 : $tags[$tag] + 1);
                }
            }
        }
        arsort($tags); // Sort tags by usage (most used tag first)
        return $tags;
    }

    // Returns the list of days containing articles (oldest first)
    // Output: An array containing days (in format YYYYMMDD).
    public function days()
    {
        $linkdays = array();
        foreach (array_keys($this->links) as $day) {
            $linkdays[substr($day, 0, 8)] = 0;
        }
        $linkdays = array_keys($linkdays);
        sort($linkdays);

        return $linkdays;
    }
}

// ------------------------------------------------------------------------------------------
// Ouput the last N links in RSS 2.0 format.
function showRSS()
{
    header('Content-Type: application/rss+xml; charset=utf-8');

    // $usepermalink : If true, use permalink instead of final link.
    // User just has to add 'permalink' in URL parameters. eg. http://mysite.com/shaarli/?do=rss&permalinks
    $usepermalinks = isset($_GET['permalinks']);

    // Cache system
    $query = $_SERVER['QUERY_STRING'];
    $cache = new pageCache(pageUrl(), startsWith($query, 'do=rss') && !isLoggedIn());
    $cached = $cache->cachedVersion();
    if (!empty($cached)) {
        echo $cached;
        exit;
    }

    // If cached was not found (or not usable), then read the database and build the response:
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).

    // Optionnaly filter the results:
    $linksToDisplay = array();
    if (!empty($_GET['searchterm'])) {
        $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
    } elseif (!empty($_GET['searchtags'])) {
        $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
    } else {
        $linksToDisplay = $LINKSDB;
    }
    $nblinksToDisplay = 50;  // Number of links to display.
    if (!empty($_GET['nb'])) {
        // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.

        $nblinksToDisplay = $_GET['nb'] == 'all' ? count($linksToDisplay) : max($_GET['nb'] + 0, 1);
    }

    $pageaddr = htmlspecialchars(indexUrl());
    echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/">';
    echo '<channel><title>'.htmlspecialchars($GLOBALS['title']).'</title><link>'.$pageaddr.'</link>';
    echo '<description>Shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n\n";
    if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) {
        echo '<!-- PubSubHubbub Discovery -->';
        echo '<link rel="hub" href="'.htmlspecialchars($GLOBALS['config']['PUBSUBHUB_URL']).'" xmlns="http://www.w3.org/2005/Atom" />';
        echo '<link rel="self" href="'.htmlspecialchars($pageaddr).'?do=rss" xmlns="http://www.w3.org/2005/Atom" />';
        echo '<!-- End Of PubSubHubbub Discovery -->';
    }
    $i = 0;
    $keys = array();
    foreach ($linksToDisplay as $key => $value) {
        $keys[] = $key;
    }  // No, I can't use array_keys().
    while ($i < $nblinksToDisplay && $i < count($keys)) {
        $link = $linksToDisplay[$keys[$i]];
        $guid = $pageaddr.'?'.smallHash($link['linkdate']);
        $rfc822date = linkdate2rfc822($link['linkdate']);
        $absurl = htmlspecialchars($link['url']);
        if (startsWith($absurl, '?')) {
            $absurl = $pageaddr.$absurl;
        }  // make permalink URL absolute
        if ($usepermalinks === true) {
            echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$guid.'</link>';
        } else {
            echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$absurl.'</link>';
        }
        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) {
            echo '<pubDate>'.htmlspecialchars($rfc822date)."</pubDate>\n";
        }
        if ($link['tags'] != '') {
            // Adding tags to each RSS entry (as mentioned in RSS specification)

            foreach (explode(' ', $link['tags']) as $tag) {
                echo '<category domain="'.htmlspecialchars($pageaddr).'">'.htmlspecialchars($tag).'</category>'."\n";
            }
        }

        // Add permalink in description
        $descriptionlink = '(<a href="'.$guid.'">Permalink</a>)';
        // If user wants permalinks first, put the final link in description
        if ($usepermalinks === true) {
            $descriptionlink = '(<a href="'.$absurl.'">Link</a>)';
        }
        if (strlen($link['description']) > 0) {
            $descriptionlink = $descriptionlink;
        }
        if (!empty($link['via'])) {
            $via = 'Origin => <a href="'.htmlspecialchars($link['via']).'">'.htmlspecialchars(getJustDomain($link['via'])).'</a><br/>';
        } else {
            $via = '';
        }
        if ($GLOBALS['config']['ENABLE_MARKDOWN'] === true) {
            $Parsedown = new Parsedown();
            echo '<description><![CDATA['.$Parsedown->setMarkupEscaped(true)->setBreaksEnabled(true)->text($link['description']).$via.$descriptionlink.']]>
          </description>'."\n</item>\n";
        } else {
            echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))).$via.$descriptionlink.']]>
          </description>'."\n</item>\n";
        }
        ++$i;
    }
    echo '</channel></rss><!-- Cached version of '.htmlspecialchars(pageUrl()).' -->';

    $cache->cache(ob_get_contents());
    ob_end_flush();
    exit;
}

// ------------------------------------------------------------------------------------------
// Ouput the last N links in ATOM format.
function showATOM()
{
    header('Content-Type: application/atom+xml; charset=utf-8');

    // $usepermalink : If true, use permalink instead of final link.
    // User just has to add 'permalink' in URL parameters. eg. http://mysite.com/shaarli/?do=atom&permalinks
    $usepermalinks = isset($_GET['permalinks']);

    // Cache system
    $query = $_SERVER['QUERY_STRING'];
    $cache = new pageCache(pageUrl(), startsWith($query, 'do=atom') && !isLoggedIn());
    $cached = $cache->cachedVersion();
    if (!empty($cached)) {
        echo $cached;
        exit;
    }
    // If cached was not found (or not usable), then read the database and build the response:

    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).

    // Optionnaly filter the results:
    $linksToDisplay = array();
    if (!empty($_GET['searchterm'])) {
        $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
    } elseif (!empty($_GET['searchtags'])) {
        $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
    } else {
        $linksToDisplay = $LINKSDB;
    }
    $nblinksToDisplay = 50;  // Number of links to display.
    if (!empty($_GET['nb'])) {
        // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.

        $nblinksToDisplay = $_GET['nb'] == 'all' ? count($linksToDisplay) : max($_GET['nb'] + 0, 1);
    }

    $pageaddr = htmlspecialchars(indexUrl());
    $latestDate = '';
    $entries = '';
    $i = 0;
    $keys = array();
    foreach ($linksToDisplay as $key => $value) {
        $keys[] = $key;
    }  // No, I can't use array_keys().
    while ($i < $nblinksToDisplay && $i < count($keys)) {
        $link = $linksToDisplay[$keys[$i]];
        $guid = $pageaddr.'?'.smallHash($link['linkdate']);
        $iso8601date = linkdate2iso8601($link['linkdate']);
        $latestDate = max($latestDate, $iso8601date);
        $absurl = htmlspecialchars($link['url']);
        if (startsWith($absurl, '?')) {
            $absurl = $pageaddr.$absurl;
        }  // make permalink URL absolute
        $entries .= '<entry><title>'.htmlspecialchars($link['title']).'</title>';
        if ($usepermalinks === true) {
            $entries .= '<link href="'.$guid.'" /><id>'.$guid.'</id>';
        } else {
            $entries .= '<link href="'.$absurl.'" /><id>'.$guid.'</id>';
        }
        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) {
            $entries .= '<updated>'.htmlspecialchars($iso8601date).'</updated>';
        }

        // Add permalink in description
        $descriptionlink = htmlspecialchars('(<a href="'.$guid.'">Permalink</a>)');
        if (isset($link['via']) && !empty($link['via'])) {
            $via = htmlspecialchars('Origin => <a href="'.$link['via'].'">'.getJustDomain($link['via']).'</a><br/>');
        } else {
            $via = '';
        }
        // If user wants permalinks first, put the final link in description
        if ($usepermalinks === true) {
            $descriptionlink = htmlspecialchars('(<a href="'.$absurl.'">Link</a>)');
        }
        if (strlen($link['description']) > 0) {
            $descriptionlink = $descriptionlink;
        }
        if ($GLOBALS['config']['ENABLE_MARKDOWN'] === true) {
            $Parsedown = new Parsedown();
            $entries .= '<content type="html">'.htmlspecialchars($Parsedown->setMarkupEscaped(true)->setBreaksEnabled(true)->text($link['description'])).' '.$via.$descriptionlink."</content>\n";
        } else {
            $entries .= '<content type="html">'.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))))).$via.$descriptionlink."</content>\n";
        }
        if ($link['tags'] != '') {
            // Adding tags to each ATOM entry (as mentioned in ATOM specification)

            foreach (explode(' ', $link['tags']) as $tag) {
                $entries .= '<category scheme="'.htmlspecialchars($pageaddr, ENT_QUOTES).'" term="'.htmlspecialchars($tag, ENT_QUOTES).'" />'."\n";
            }
        }
        $entries .= "</entry>\n";
        ++$i;
    }
    $feed = '<?xml version="1.0" encoding="UTF-8"?><feed xmlns="http://www.w3.org/2005/Atom">';
    $feed .= '<title>'.htmlspecialchars($GLOBALS['title']).'</title>';
    if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) {
        $feed .= '<updated>'.htmlspecialchars($latestDate).'</updated>';
    }
    $feed .= '<link rel="self" href="'.htmlspecialchars(serverUrl().$_SERVER['REQUEST_URI']).'" />';
    if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) {
        $feed .= '<!-- PubSubHubbub Discovery -->';
        $feed .= '<link rel="hub" href="'.htmlspecialchars($GLOBALS['config']['PUBSUBHUB_URL']).'" />';
        $feed .= '<!-- End Of PubSubHubbub Discovery -->';
    }
    $feed .= '<author><name>'.htmlspecialchars($pageaddr).'</name><uri>'.htmlspecialchars($pageaddr).'</uri></author>';
    $feed .= '<id>'.htmlspecialchars($pageaddr).'</id>'."\n\n"; // Yes, I know I should use a real IRI (RFC3987), but the site URL will do.
    $feed .= $entries;
    $feed .= '</feed><!-- Cached version of '.htmlspecialchars(pageUrl()).' -->';
    echo $feed;

    $cache->cache(ob_get_contents());
    ob_end_flush();
    exit;
}

// ------------------------------------------------------------------------------------------
// Daily RSS feed: 1 RSS entry per day giving all the links on that day.
// Gives the last 7 days (which have links).
// This RSS feed cannot be filtered.
function showDailyRSS()
{
    // Cache system
    $query = $_SERVER['QUERY_STRING'];
    $cache = new pageCache(pageUrl(), startsWith($query, 'do=dailyrss') && !isLoggedIn());
    $cached = $cache->cachedVersion();
    if (!empty($cached)) {
        echo $cached;
        exit;
    }
    // If cached was not found (or not usable), then read the database and build the response:
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).

    /* Some Shaarlies may have very few links, so we need to look
       back in time (rsort()) until we have enough days ($nb_of_days).
    */
    $linkdates = array();
    foreach ($LINKSDB as $linkdate => $value) {
        $linkdates[] = $linkdate;
    }
    rsort($linkdates);
    $nb_of_days = 7; // We take 7 days.
    $today = Date('Ymd');
    $days = array();
    foreach ($linkdates as $linkdate) {
        $day = substr($linkdate, 0, 8); // Extract day (without time)
        if (strcmp($day, $today) < 0) {
            if (empty($days[$day])) {
                $days[$day] = array();
            }
            $days[$day][] = $linkdate;
        }
        if (count($days) > $nb_of_days) {
            break;
        } // Have we collected enough days ?
    }

    // Build the RSS feed.
    header('Content-Type: application/rss+xml; charset=utf-8');
    $pageaddr = htmlspecialchars(indexUrl());
    echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0">';
    echo '<?xml-stylesheet type="text/css" href="http://shaarli.local/inc/shaarli.css?version=0.0.41+beta" ?>';
    echo '<?xml-stylesheet type="text/css" href="http://shaarli.local/inc/user.css?version=0.0.41%20beta" ?>';
    echo '<channel><title>Daily - '.htmlspecialchars($GLOBALS['title']).'</title><link>'.$pageaddr.'</link>';
    echo '<description>Daily shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n";

    foreach ($days as $day => $linkdates) {
        // For each day.

        $daydate = utf8_encode(strftime('%A %d, %B %Y', linkdate2timestamp($day.'_000000'))); // Full text date
        $rfc822date = linkdate2rfc822($day.'_000000');
        $absurl = htmlspecialchars(indexUrl().'?do=daily&day='.$day);  // Absolute URL of the corresponding "Daily" page.
        echo '<item><title>'.htmlspecialchars($GLOBALS['title'].' - '.$daydate).'</title><guid>'.$absurl.'</guid><link>'.$absurl.'</link>';
        echo '<pubDate>'.htmlspecialchars($rfc822date).'</pubDate>';

        // Build the HTML body of this RSS entry.
        $html = '';
        $href = '';
        $links = array();
        // We pre-format some fields for proper output.
        foreach ($linkdates as $linkdate) {
            $l = $LINKSDB[$linkdate];
            $l['formatedDescription'] = nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($l['description']))));
            $l['thumbnail'] = thumbnail($l['url']);
            $l['localdate'] = linkdate2locale($l['linkdate']);
            if (startsWith($l['url'], '?')) {
                $l['url'] = indexUrl().$l['url'];
            }  // make permalink URL absolute
            $links[$linkdate] = $l;
        }
        // Then build the HTML for this day:
        $tpl = new RainTPL();
        $tpl->assign('links', $links);
        $html = $tpl->draw('dailyrss', $return_string = true);
        echo "\n";
        echo '<description><![CDATA['.$html.']]></description>'."\n</item>\n\n";
    }
    echo '</channel></rss><!-- Cached version of '.htmlspecialchars(pageUrl()).' -->';

    $cache->cache(ob_get_contents());
    ob_end_flush();
    exit;
}

// "Daily" page.
function showDaily()
{
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).

    $day = Date('Ymd', strtotime('-1 day')); // Yesterday, in format YYYYMMDD.
    if (isset($_GET['day'])) {
        $day = $_GET['day'];
    }

    $days = $LINKSDB->days();
    $i = array_search($day, $days);
    if ($i == false) {
        $i = count($days) - 1;
        $day = $days[$i];
    }
    $previousday = '';
    $nextday = '';
    if ($i !== false) {
        if ($i > 1) {
            $previousday = $days[$i - 1];
        }
        if ($i < count($days) - 1) {
            $nextday = $days[$i + 1];
        }
    }

    $linksToDisplay = $LINKSDB->filterDay($day);
    // We pre-format some fields for proper output.
    foreach ($linksToDisplay as $key => $link) {
        $taglist = explode(' ', $link['tags']);
        uasort($taglist, 'strcasecmp');
        $linksToDisplay[$key]['taglist'] = $taglist;
        $linksToDisplay[$key]['formatedDescription'] = nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))));
        $linksToDisplay[$key]['thumbnail'] = thumbnail($link['url']);
    }

    /* We need to spread the articles on 3 columns.
       I did not want to use a javascript lib like http://masonry.desandro.com/
       so I manually spread entries with a simple method: I roughly evaluate the
       height of a div according to title and description length.
    */
    $columns = array(array(), array(), array()); // Entries to display, for each column.
    $fill = array(0, 0, 0);  // Rough estimate of columns fill.
    foreach ($linksToDisplay as $key => $link) {
        // Roughly estimate length of entry (by counting characters)
        // Title: 30 chars = 1 line. 1 line is 30 pixels height.
        // Description: 836 characters gives roughly 342 pixel height.
        // This is not perfect, but it's usually ok.
        $length = strlen($link['title']) + (342 * strlen($link['description'])) / 836;
        if ($link['thumbnail']) {
            $length += 100;
        } // 1 thumbnails roughly takes 100 pixels height.
        // Then put in column which is the less filled:
        $smallest = min($fill); // find smallest value in array.
        $index = array_search($smallest, $fill); // find index of this smallest value.
        array_push($columns[$index], $link); // Put entry in this column.
        $fill[$index] += $length;
    }
    $PAGE = new pageBuilder();
    $PAGE->assign('linksToDisplay', $linksToDisplay);
    $PAGE->assign('linkcount', count($LINKSDB));
    $PAGE->assign('col1', $columns[0]);
    $PAGE->assign('col1', $columns[0]);
    $PAGE->assign('col2', $columns[1]);
    $PAGE->assign('col3', $columns[2]);
    $PAGE->assign('day', utf8_encode(strftime('%A %d, %B %Y', linkdate2timestamp($day.'_000000'))));
    $PAGE->assign('previousday', $previousday);
    $PAGE->assign('nextday', $nextday);
    $PAGE->renderPage('daily');
    exit;
}

// ------------------------------------------------------------------------------------------
// Render HTML page (according to URL parameters and user rights)
function renderPage()
{
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).

    // -------- Display login form.
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=login')) {
        if ($GLOBALS['config']['OPEN_SHAARLI']) {
            header('Location: ?');
            exit;
        }  // No need to login for open Shaarli
        $token = '';
        if (ban_canLogin()) {
            $token = getToken();
        } // Do not waste token generation if not useful.
        $PAGE = new pageBuilder();
        $PAGE->assign('token', $token);
        $PAGE->assign('returnurl', (isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
        $PAGE->renderPage('loginform');
        exit;
    }
    // -------- User wants to logout.
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=logout')) {
        invalidateCaches();
        logout();
        header('Location: ?');
        exit;
    }

    // -------- Picture wall
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=picwall')) {
        // Optionnaly filter the results:
        $links = array();
        if (!empty($_GET['searchterm'])) {
            $links = $LINKSDB->filterFulltext($_GET['searchterm']);
        } elseif (!empty($_GET['searchtags'])) {
            $links = $LINKSDB->filterTags(trim($_GET['searchtags']));
        } else {
            $links = $LINKSDB;
        }
        $body = '';
        $linksToDisplay = array();

        // Get only links which have a thumbnail.
        foreach ($links as $link) {
            $permalink = '?'.htmlspecialchars(smallhash($link['linkdate']), ENT_QUOTES);
            $thumb = lazyThumbnail($link['url'], $permalink);
            if ($thumb != '') {
                // Only output links which have a thumbnail.

                $link['thumbnail'] = $thumb; // Thumbnail HTML code.
                $link['permalink'] = $permalink;
                $linksToDisplay[] = $link; // Add to array.
            }
        }
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('linksToDisplay', $linksToDisplay);
        $PAGE->renderPage('picwall');
        exit;
    }

    // -------- Tag cloud
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=tagcloud')) {
        $tags = $LINKSDB->allTags();
        // We sort tags alphabetically, then choose a font size according to count.
        // First, find max value.
        $maxcount = 0;
        foreach ($tags as $key => $value) {
            $maxcount = max($maxcount, $value);
        }
        $linkCount = count($LINKSDB);
        ksort($tags);
        $tagList = array();
        foreach ($tags as $key => $value) {
            // Tag font size scaling: default 15 and 30 logarithm bases affect scaling, 22 and 6 are arbitrary font sizes for max and min sizes.

            $tagList[$key] = array('count' => $value, 'size' => log($value, 5) / log($maxcount, 3) * (4.8 - 0.8) + 0.8);
        }
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('tags', $tagList);
        $PAGE->renderPage('tagcloud');
        exit;
    }

    // Display openseach plugin (XML)
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=opensearch')) {
        header('Content-Type: application/xml; charset=utf-8');
        $PAGE = new pageBuilder();
        $PAGE->assign('serverurl', $GLOBALS['title']);
        $PAGE->assign('pagetitle', $GLOBALS['title']);
        $PAGE->renderPage('opensearch');
        exit;
    }

    // -------- User clicks on a tag in a link: The tag is added to the list of searched tags (searchtags=...)
    if (isset($_GET['addtag'])) {
        // Get previous URL (http_referer) and add the tag to the searchtags parameters in query.
        if (empty($_SERVER['HTTP_REFERER'])) {
            header('Location: ?searchtags='.urlencode($_GET['addtag']));
            exit;
        } // In case browser does not send HTTP_REFERER
        parse_str(parse_url($_SERVER['HTTP_REFERER'], PHP_URL_QUERY), $params);
        $params['searchtags'] = (empty($params['searchtags']) ?  trim($_GET['addtag']) : trim($params['searchtags']).' '.trim($_GET['addtag']));
        unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
        header('Location: ?'.http_build_query($params));
        exit;
    }

    // -------- User clicks on a tag in result count: Remove the tag from the list of searched tags (searchtags=...)
    if (isset($_GET['removetag'])) {
        // Get previous URL (http_referer) and remove the tag from the searchtags parameters in query.
        if (empty($_SERVER['HTTP_REFERER'])) {
            header('Location: ?');
            exit;
        } // In case browser does not send HTTP_REFERER
        parse_str(parse_url($_SERVER['HTTP_REFERER'], PHP_URL_QUERY), $params);
        if (isset($params['searchtags'])) {
            $tags = explode(' ', $params['searchtags']);
            $tags = array_diff($tags, array($_GET['removetag'])); // Remove value from array $tags.
            if (count($tags) == 0) {
                unset($params['searchtags']);
            } else {
                $params['searchtags'] = implode(' ', $tags);
            }
            unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
        }
        header('Location: ?'.http_build_query($params));
        exit;
    }

    // -------- User wants to change the number of links per page (linksperpage=...)
    if (isset($_GET['linksperpage'])) {
        if (is_numeric($_GET['linksperpage'])) {
            $_SESSION['LINKS_PER_PAGE'] = abs(intval($_GET['linksperpage']));
        }
        // Make sure the referer is from Shaarli itself.
        $referer = '?';
        if (!empty($_SERVER['HTTP_REFERER']) && strcmp(parse_url($_SERVER['HTTP_REFERER'], PHP_URL_HOST), $_SERVER['HTTP_HOST']) == 0) {
            $referer = $_SERVER['HTTP_REFERER'];
        }
        header('Location: '.$referer);
        exit;
    }

    // -------- User wants to see only private links (toggle)
    if (isset($_GET['privateonly'])) {
        if (empty($_SESSION['privateonly'])) {
            $_SESSION['privateonly'] = 1; // See only private links
        } else {
            unset($_SESSION['privateonly']); // See all links
        }
        // Make sure the referer is from Shaarli itself.
        $referer = '?';
        if (!empty($_SERVER['HTTP_REFERER']) && strcmp(parse_url($_SERVER['HTTP_REFERER'], PHP_URL_HOST), $_SERVER['HTTP_HOST']) == 0) {
            $referer = $_SERVER['HTTP_REFERER'];
        }
        header('Location: '.$referer);
        exit;
    }

    // -------- Handle other actions allowed for non-logged in users:
    if (!isLoggedIn()) {
        // User tries to post new link but is not loggedin:
        // Show login screen, then redirect to ?post=...
        if (isset($_GET['post'])) {
            header('Location: ?do=login&post='.urlencode($_GET['post']).(!empty($_GET['title']) ? '&title='.urlencode($_GET['title']) : '').(!empty($_GET['source']) ? '&source='.urlencode($_GET['source']) : '')); // Redirect to login page, then back to post link.
            exit;
        }

        // Same case as above except that user tried to access ?do=addlink without being logged in
        // Note: passing empty parameters makes Shaarli generate default URLs and descriptions.
        if (isset($_GET['do']) && $_GET['do'] === 'addlink') {
            header('Location: ?do=login&post=');
            exit;
        }

        $PAGE = new pageBuilder();
        buildLinkList($PAGE, $LINKSDB); // Compute list of links to display
        $PAGE->renderPage('linklist');
        exit; // Never remove this one ! All operations below are reserved for logged in user.
    }

    // -------- All other functions are reserved for the registered user:

    // -------- Display the Tools menu if requested (import/export/bookmarklet...)
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=tools')) {
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('pageabsaddr', indexUrl());
        $PAGE->renderPage('tools');
        exit;
    }

    // -------- User wants to change his/her password.
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=changepasswd')) {
        if ($GLOBALS['config']['OPEN_SHAARLI']) {
            die('You are not supposed to change a password on an Open Shaarli.');
        }
        if (!empty($_POST['setpassword']) && !empty($_POST['oldpassword'])) {
            if (!tokenOk($_POST['token'])) {
                die('Wrong token.');
            } // Go away !

            // Make sure old password is correct.
            $oldhash = sha1($_POST['oldpassword'].$GLOBALS['login'].$GLOBALS['salt']);
            if ($oldhash != $GLOBALS['hash']) {
                echo '<script>alert("The old password is not correct.");document.location=\'?do=changepasswd\';</script>';
                exit;
            }
            // Save new password
            $GLOBALS['salt'] = sha1(uniqid('', true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
            $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
            writeConfig();
            echo '<script>alert("Your password has been changed.");document.location=\'?do=tools\';</script>';
            exit;
        } else {
            // show the change password form.

            $PAGE = new pageBuilder();
            $PAGE->assign('linkcount', count($LINKSDB));
            $PAGE->assign('token', getToken());
            $PAGE->renderPage('changepassword');
            exit;
        }
    }

    // -------- User wants to change configuration
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=configure')) {
        if (!empty($_POST['title'])) {
            if (!tokenOk($_POST['token'])) {
                die('Wrong token.');
            } // Go away !
            $tz = 'UTC';
            if (!empty($_POST['continent']) && !empty($_POST['city'])) {
                if (isTZvalid($_POST['continent'], $_POST['city'])) {
                    $tz = $_POST['continent'].'/'.$_POST['city'];
                }
            }
            $GLOBALS['timezone'] = $tz;
            $GLOBALS['title'] = htmlentities(strip_tags($_POST['title']));
            $GLOBALS['titleLink'] = htmlentities(strip_tags($_POST['titleLink']));
            $GLOBALS['redirector'] = $_POST['redirector'];
            $GLOBALS['disablesessionprotection'] = !empty($_POST['disablesessionprotection']);
            $GLOBALS['disablejquery'] = !empty($_POST['disablejquery']);
            $GLOBALS['privateLinkByDefault'] = !empty($_POST['privateLinkByDefault']);
            $GLOBALS['config']['ENABLE_RSS_PERMALINKS'] = !empty($_POST['enableRssPermalinks']);
            $GLOBALS['config']['ENABLE_UPDATECHECK'] = !empty($_POST['updateCheck']);
            $GLOBALS['config']['ENABLE_MARKDOWN'] = !empty($_POST['enableMarkdown']);
            $GLOBALS['config']['HIDE_TIMESTAMPS'] = !empty($_POST['hideTimestamps']);
            $GLOBALS['config']['BAN_AFTER'] = (int) $_POST['banAfter'];
            $GLOBALS['config']['BAN_DURATION'] = (int) $_POST['banDuration'];
            $GLOBALS['config']['THEME'] = htmlentities(strip_tags($_POST['theme']));
            $GLOBALS['config']['LINKS_PER_PAGE'] = (int) $_POST['linkPerPage'];
            $GLOBALS['config']['ENABLE_THUMBNAILS'] = !empty($_POST['enableThumbnails']);
            $GLOBALS['config']['ENABLE_FAVICON'] = !empty($_POST['enableFavicon']);
            $GLOBALS['config']['ENABLE_LOCALCACHE'] = !empty($_POST['enableCache']);
            $GLOBALS['config']['externalThumbshot'] = $_POST['externalThumbshot'];
            $GLOBALS['config']['contactLink'] = $_POST['contactLink'];
            $_SESSION['LINKS_PER_PAGE'] = (int) $_POST['linkPerPage'];
            $GLOBALS['config']['DATE_FORMAT'] = strip_tags($_POST['dateFormat']);
            $GLOBALS['config']['WALLABAG_URL'] = $_POST['wallabagUrl'];
            $GLOBALS['config']['WALLABAG_VERSION'] = (int)$_POST['wallabagVersion'];

            writeConfig();
            echo '<script>alert("Configuration was saved.");document.location=\'?do=configure\';</script>';
            exit;
        } else {
            // Show the configuration form.

            $PAGE = new pageBuilder();
            $PAGE->assign('themes', getAllTheme());
            $PAGE->assign('linkcount', count($LINKSDB));
            $PAGE->assign('token', getToken());
            $PAGE->assign('title', htmlspecialchars(empty($GLOBALS['title']) ? '' : $GLOBALS['title'], ENT_QUOTES));
            $PAGE->assign('redirector', htmlspecialchars(empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'], ENT_QUOTES));
            list($timezone_form, $timezone_js) = templateTZform($GLOBALS['timezone']);
            $PAGE->assign('timezone_form', $timezone_form); // FIXME: put entire tz form generation in template ?
            $PAGE->assign('timezone_js', $timezone_js);
            if ($_GET['config'] === 'myshaarli') {
                raintpl::$tpl_dir = 'tpl/myShaarli/';
                $PAGE->renderPage('configure');
            } else {
                $PAGE->renderPage('configure');
            }
            exit;
        }
    }

    // -------- User wants to rename a tag or delete it
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=changetag')) {
        if (empty($_POST['fromtag']) && empty($_POST['tagToDelete'])) {
            $PAGE = new pageBuilder();
            $PAGE->assign('linkcount', count($LINKSDB));
            $PAGE->assign('token', getToken());
            $PAGE->renderPage('changetag');
            exit;
        }
        if (!tokenOk($_POST['token'])) {
            die('Wrong token.');
        }

        // Delete a tag:
        if (!empty($_POST['deletetag']) && !empty($_POST['tagToDelete'])) {
            $needle = trim($_POST['tagToDelete']);
            $linksToAlter = $LINKSDB->filterTags($needle, true); // true for case-sensitive tag search.
            foreach ($linksToAlter as $key => $value) {
                $tags = explode(' ', trim($value['tags']));
                unset($tags[array_search($needle, $tags)]); // Remove tag.
                $value['tags'] = trim(implode(' ', $tags));
                $LINKSDB[$key] = $value;
            }
            $LINKSDB->savedb(); // save to disk
            echo '<script>alert("Tag was removed from '.count($linksToAlter).' links.");document.location=\'?\';</script>';
            exit;
        }

        // Rename a tag:
        if (!empty($_POST['renametag']) && !empty($_POST['fromtag']) && !empty($_POST['totag'])) {
            $needle = trim($_POST['fromtag']);
            $linksToAlter = $LINKSDB->filterTags($needle, true); // true for case-sensitive tag search.
            foreach ($linksToAlter as $key => $value) {
                $tags = explode(' ', trim($value['tags']));
                $tags[array_search($needle, $tags)] = trim($_POST['totag']); // Remplace tags value.
                $value['tags'] = trim(implode(' ', $tags));
                $LINKSDB[$key] = $value;
            }
            $LINKSDB->savedb(); // save to disk
            echo '<script>alert("Tag was renamed in '.count($linksToAlter).' links.");document.location=\'?searchtags='.urlencode($_POST['totag']).'\';</script>';
            exit;
        }
    }

    // -------- User wants to add a link without using the bookmarklet: show form.
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=addlink')) {
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->renderPage('addlink');
        exit;
    }

    // -------- User clicked the "Save" button when editing a link: Save link to database.
    if (isset($_POST['save_edit'])) {
        if (!tokenOk($_POST['token'])) {
            die('Wrong token.');
        } // Go away !
        $tags = trim(preg_replace('/\s\s+/', ' ', $_POST['lf_tags'])); // Remove multiple spaces.
        $linkdate = $_POST['lf_linkdate'];
        $url = trim($_POST['lf_url']);
        if (!startsWith($url, 'http:') && !startsWith($url, 'https:') && !startsWith($url, 'ftp:') && !startsWith($url, 'magnet:') && !startsWith($url, '?') && !startsWith($url, 'javascript:')) {
            $url = 'http://'.$url;
        }
        $link = array('title' => trim($_POST['lf_title']), 'url' => $url, 'description' => trim($_POST['lf_description']), 'private' => (isset($_POST['lf_private']) ? 1 : 0),
                      'linkdate' => $linkdate, 'tags' => str_replace(',', ' ', $tags), 'via' => trim($_POST['lf_via']), );
        if ($link['title'] == '') {
            $link['title'] = $link['url'];
        } // If title is empty, use the URL as title.
        $LINKSDB[$linkdate] = $link;
        $LINKSDB->savedb(); // save to disk
        pubsubhub();

        // If we are called from the bookmarklet, we must close the popup:
        if (isset($_GET['source']) && ($_GET['source'] == 'bookmarklet' || $_GET['source'] == 'firefoxsocialapi')) {
            echo '<script>self.close();</script>';
            exit;
        }
        $returnurl = (isset($_POST['returnurl']) ? $_POST['returnurl'] : '?');
        $returnurl .= '#'.smallHash($linkdate);  // Scroll to the link which has been edited.
        if (strstr($returnurl, 'do=addlink')) {
            $returnurl = '?';
        } //if we come from ?do=addlink, set returnurl to homepage instead
        header('Location: '.$returnurl); // After saving the link, redirect to the page the user was on.
        exit;
    }

    // -------- User clicked the "Cancel" button when editing a link.
    if (isset($_POST['cancel_edit'])) {
        // If we are called from the bookmarklet, we must close the popup;
        if (isset($_GET['source']) && ($_GET['source'] == 'bookmarklet' || $_GET['source'] == 'firefoxsocialapi')) {
            echo '<script>self.close();</script>';
            exit;
        }
        $returnurl = (isset($_POST['returnurl']) ? $_POST['returnurl'] : '?');
        $returnurl .= '#'.smallHash($_POST['lf_linkdate']);  // Scroll to the link which has been edited.
        header('Location: '.$returnurl); // After canceling, redirect to the page the user was on.
        exit;
    }

    // -------- User clicked the "Delete" button when editing a link : Delete link from database.
    if (isset($_POST['delete_link'])) {
        if (!tokenOk($_POST['token'])) {
            die('Wrong token.');
        }
        // We do not need to ask for confirmation:
        // - confirmation is handled by javascript
        // - we are protected from XSRF by the token.
        $linkdate = $_POST['lf_linkdate'];
        unset($LINKSDB[$linkdate]);
        $LINKSDB->savedb(); // save to disk

        // If we are called from the bookmarklet, we must close the popup:
        if (isset($_GET['source']) && $_GET['source'] == 'bookmarklet') {
            echo '<script>self.close();</script>';
            exit;
        }
        header('Location: ?'); // After deleting the link, redirect to the home page.
        exit;
    }

    // -------- User clicked the "EDIT" button on a link: Display link edit form.
    if (isset($_GET['edit_link'])) {
        $link = $LINKSDB[$_GET['edit_link']];  // Read database
        if (!$link) {
            header('Location: ?');
            exit;
        } // Link not found in database.
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('link', $link);
        $PAGE->assign('link_is_new', false);
        $PAGE->assign('token', getToken()); // XSRF protection.
        $PAGE->assign('http_referer', (isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
        $PAGE->renderPage('editlink');
        exit;
    }

    // -------- User want to post a new link: Display link edit form.
    if (isset($_GET['post'])) {
        $url = $_GET['post'];

        // We remove the annoying parameters added by FeedBurner and GoogleFeedProxy (?utm_source=...)
        $i = stripos($url, '&utm_source=');
        if ($i !== false) {
            $url = substr($url, 0, $i);
        }
        $i = stripos($url, '?utm_source=');
        if ($i !== false) {
            $url = substr($url, 0, $i);
        }
        $i = stripos($url, '#xtor=RSS-');
        if ($i !== false) {
            $url = substr($url, 0, $i);
        }

        $link_is_new = false;
        $link = $LINKSDB->getLinkFromUrl($url); // Check if URL is not already in database (in this case, we will edit the existing link)
        if (!$link) {
            $link_is_new = true;  // This is a new link
            $linkdate = strval(date('Ymd_His'));
            // Get title if it was provided in URL (by the bookmarklet).
            $title = empty($_GET['title']) ? '' : htmlspecialchars($_GET['title']);
            // Get description if it was provided in URL (by the bookmarklet). [Bronco added that]
            $description = (empty($_GET['description']) ? '' : htmlspecialchars($_GET['description']));
            $tags = (empty($_GET['tags']) ? '' : htmlspecialchars($_GET['tags']));
            $via = (empty($_GET['via']) ? '' : htmlspecialchars($_GET['via']));
            $private = (!empty($_GET['private']) && $_GET['private'] === '1' ? 1 : 0);
            if (($url != '') && parse_url($url, PHP_URL_SCHEME) == '') {
                $url = 'http://'.$url;
            }
            // If this is an HTTP link, we try go get the page to extact the title (otherwise we will to straight to the edit form.)
            if (empty($title) && parse_url($url, PHP_URL_SCHEME) == 'http') {
                list($status, $headers, $data) = getHTTP($url, 4); // Short timeout to keep the application responsive.
                // FIXME: Decode charset according to specified in either 1) HTTP response headers or 2) <head> in html
                if (strpos($status, '200 OK') !== false) {
                    // Look for charset in html header.
                        preg_match('#<meta .*charset=.*>#Usi', $data, $meta);

                        // If found, extract encoding.
                        if (!empty($meta[0])) {
                            // Get encoding specified in header.
                            preg_match('#charset="?(.*)"#si', $meta[0], $enc);
                            // If charset not found, use utf-8.
                            $html_charset = (!empty($enc[1])) ? strtolower($enc[1]) : 'utf-8';
                        } else {
                            $html_charset = 'utf-8';
                        }

                        // Extract title
                        $title = html_extract_title($data);
                    if (!empty($title)) {
                        // Re-encode title in utf-8 if necessary.
                            $title = ($html_charset == 'iso-8859-1') ? utf8_encode($title) : $title;
                    }
                }
            }
            if ($url == '') {
                // In case of empty URL, this is just a text (with a link that points to itself)

                $url = '?'.smallHash($linkdate);
                $title = 'Note: ';
                $tags .= 'note ';
            }
            $link = array('linkdate' => $linkdate, 'title' => $title, 'url' => $url, 'description' => $description, 'tags' => $tags, 'via' => $via, 'private' => $private);
        }

        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('link', $link);
        $PAGE->assign('link_is_new', $link_is_new);
        $PAGE->assign('token', getToken()); // XSRF protection.
        $PAGE->assign('http_referer', (isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
        $PAGE->renderPage('editlink');
        exit;
    }

    // -------- Export as Netscape Bookmarks HTML file.
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=export')) {
        if (empty($_GET['what'])) {
            $PAGE = new pageBuilder();
            $PAGE->assign('linkcount', count($LINKSDB));
            $PAGE->renderPage('export');
            exit;
        }
        $exportWhat = $_GET['what'];
        if (!array_intersect(array('all', 'public', 'private'), array($exportWhat))) {
            die('What are you trying to export ???');
        }

        header('Content-Type: text/html; charset=utf-8');
        header('Content-disposition: attachment; filename=bookmarks_'.$exportWhat.'_'.strval(date('Ymd_His')).'.html');
        $currentdate = date('Y/m/d H:i:s');
        echo <<<HTML
<!DOCTYPE NETSCAPE-Bookmark-file-1>
<!-- This is an automatically generated file.
     It will be read and overwritten.
     DO NOT EDIT! -->
<!-- Shaarli {$exportWhat} bookmarks export on {$currentdate} -->
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=UTF-8">
<TITLE>Bookmarks</TITLE>
<H1>Bookmarks</H1>
HTML;
        foreach ($LINKSDB as $link) {
            if ($exportWhat == 'all' ||
               ($exportWhat == 'private' && $link['private'] != 0) ||
               ($exportWhat == 'public' && $link['private'] == 0)) {
                echo '<DT><A HREF="'.htmlspecialchars($link['url']).'" ADD_DATE="'.linkdate2timestamp($link['linkdate']).'" PRIVATE="'.$link['private'].'"';
                if ($link['tags'] != '') {
                    echo ' TAGS="'.htmlspecialchars(str_replace(' ', ',', $link['tags'])).'"';
                }
                echo '>'.htmlspecialchars($link['title'])."</A>\n";
                if ($link['description'] != '') {
                    echo '<DD>'.htmlspecialchars($link['description'])."\n";
                }
            }
        }
        exit;
    }

    // -------- User is uploading a file for import
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=upload')) {
        // If file is too big, some form field may be missing.
        if (!isset($_POST['token']) || (!isset($_FILES)) || (isset($_FILES['filetoupload']['size']) && $_FILES['filetoupload']['size'] == 0)) {
            $returnurl = (empty($_SERVER['HTTP_REFERER']) ? '?' : $_SERVER['HTTP_REFERER']);
            echo '<script>alert("The file you are trying to upload is probably bigger than what this webserver can accept ('.getMaxFileSize().' bytes). Please upload in smaller chunks.");document.location=\''.htmlspecialchars($returnurl).'\';</script>';
            exit;
        }
        if (!tokenOk($_POST['token'])) {
            die('Wrong token.');
        }
        importFile();
        exit;
    }

    // -------- Show upload/import dialog:
    if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=import')) {
        $PAGE = new pageBuilder();
        $PAGE->assign('linkcount', count($LINKSDB));
        $PAGE->assign('token', getToken());
        $PAGE->assign('maxfilesize', getMaxFileSize());
        $PAGE->renderPage('import');
        exit;
    }

    // -------- Otherwise, simply display search form and links:
    $PAGE = new pageBuilder();
    $PAGE->assign('linkcount', count($LINKSDB));
    buildLinkList($PAGE, $LINKSDB); // Compute list of links to display
    $PAGE->renderPage('linklist');
    exit;
}

// -----------------------------------------------------------------------------------------------
// Process the import file form.
function importFile()
{
    if (!(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'])) {
        die('Not allowed.');
    }
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
    $filename = $_FILES['filetoupload']['name'];
    $filesize = $_FILES['filetoupload']['size'];
    $data = file_get_contents($_FILES['filetoupload']['tmp_name']);
    $private = (empty($_POST['private']) ? 0 : 1); // Should the links be imported as private ?
    $overwrite = !empty($_POST['overwrite']); // Should the imported links overwrite existing ones ?
    $import_count = 0;

    // Sniff file type:
    $type = 'unknown';
    if (startsWith($data, '<!DOCTYPE NETSCAPE-Bookmark-file-1>')) {
        $type = 'netscape';
    } // Netscape bookmark file (aka Firefox).

    // Then import the bookmarks.
    if ($type == 'netscape') {
        // This is a standard Netscape-style bookmark file.
        // This format is supported by all browsers (except IE, of course), also delicious, diigo and others.
        foreach (explode('<DT>', $data) as $html) {
            // explode is very fast

            $link = array('linkdate' => '', 'title' => '', 'url' => '', 'description' => '', 'tags' => '', 'private' => 0);
            $d = explode('<DD>', $html);
            if (startswith($d[0], '<A ')) {
                $link['description'] = (isset($d[1]) ? html_entity_decode(trim($d[1]), ENT_QUOTES, 'UTF-8') : '');  // Get description (optional)
                preg_match('!<A .*?>(.*?)</A>!i', $d[0], $matches);
                $link['title'] = (isset($matches[1]) ? trim($matches[1]) : '');  // Get title
                $link['title'] = html_entity_decode($link['title'], ENT_QUOTES, 'UTF-8');
                preg_match_all('! ([A-Z_]+)=\"(.*?)"!i', $html, $matches, PREG_SET_ORDER);  // Get all other attributes
                $raw_add_date = 0;
                foreach ($matches as $m) {
                    $attr = $m[1];
                    $value = $m[2];
                    if ($attr == 'HREF') {
                        $link['url'] = html_entity_decode($value, ENT_QUOTES, 'UTF-8');
                    } elseif ($attr == 'ADD_DATE') {
                        $raw_add_date = intval($value);
                        if ($raw_add_date > 30000000000) {
                            $raw_add_date /= 1000;
                        }    //If larger than year 2920, then was likely stored in milliseconds instead of seconds
                    } elseif ($attr == 'PRIVATE') {
                        $link['private'] = ($value == '0' ? 0 : 1);
                    } elseif ($attr == 'TAGS') {
                        $link['tags'] = html_entity_decode(str_replace(',', ' ', $value), ENT_QUOTES, 'UTF-8');
                    }
                }
                if ($link['url'] != '') {
                    if ($private == 1) {
                        $link['private'] = 1;
                    }
                    $dblink = $LINKSDB->getLinkFromUrl($link['url']); // See if the link is already in database.
                    if ($dblink == false) {  // Link not in database, let's import it...
                       if (empty($raw_add_date)) {
                           $raw_add_date = time();
                       } // In case of shitty bookmark file with no ADD_DATE

                       // Make sure date/time is not already used by another link.
                       // (Some bookmark files have several different links with the same ADD_DATE)
                       // We increment date by 1 second until we find a date which is not used in db.
                       // (so that links that have the same date/time are more or less kept grouped by date, but do not conflict.)
                       while (!empty($LINKSDB[date('Ymd_His', $raw_add_date)])) {
                           ++$raw_add_date;
                       }// Yes, I know it's ugly.
                       $link['linkdate'] = date('Ymd_His', $raw_add_date);
                        $LINKSDB[$link['linkdate']] = $link;
                        ++$import_count;
                    } else {
                        // link already present in database.

                        if ($overwrite) {   // If overwrite is required, we import link data, except date/time.
                            $link['linkdate'] = $dblink['linkdate'];
                            $LINKSDB[$link['linkdate']] = $link;
                            ++$import_count;
                        }
                    }
                }
            }
        }
        $LINKSDB->savedb();

        echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) was successfully processed: '.$import_count.' links imported.");document.location=\'?\';</script>';
    } else {
        echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) has an unknown file format. Nothing was imported.");document.location=\'?\';</script>';
    }
}

// -----------------------------------------------------------------------------------------------
// Template for the list of links (<div id="linklist">)
// This function fills all the necessary fields in the $PAGE for the template 'linklist.html'
function buildLinkList($PAGE, $LINKSDB)
{
    // ---- Filter link database according to parameters
    $linksToDisplay = array();
    $search_type = '';
    $search_crits = '';
    if (isset($_GET['searchterm'])) {
        // Fulltext search

        $linksToDisplay = $LINKSDB->filterFulltext(trim($_GET['searchterm']));
        $search_crits = htmlspecialchars(trim($_GET['searchterm']));
        $search_type = 'fulltext';
    } elseif (isset($_GET['searchtags'])) {
        // Search by tag

        $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
        $search_crits = explode(' ', trim($_GET['searchtags']));
        $search_type = 'tags';
    } elseif (isset($_SERVER['QUERY_STRING']) && preg_match('/[a-zA-Z0-9-_@]{6}(&.+?)?/', $_SERVER['QUERY_STRING'])) {
        // Detect smallHashes in URL

        $linksToDisplay = $LINKSDB->filterSmallHash(substr(trim($_SERVER['QUERY_STRING'], '/'), 0, 6));
        if (count($linksToDisplay) == 0) {
            header($_SERVER['SERVER_PROTOCOL'].' 404 Not Found');
            echo '<h1>404 Not found.</h1>Oh crap. The link you are trying to reach does not exist or has been deleted.';
            echo '<br>You would mind <a href="?">clicking here</a> ?';
            exit;
        }
        $search_type = 'permalink';
    } else {
        $linksToDisplay = $LINKSDB;
    }  // otherwise, display without filtering.

    // Option: Show only private links
    if (!empty($_SESSION['privateonly'])) {
        $tmp = array();
        foreach ($linksToDisplay as $linkdate => $link) {
            if ($link['private'] != 0) {
                $tmp[$linkdate] = $link;
            }
        }
        $linksToDisplay = $tmp;
    }

    // ---- Handle paging.
    /* Can someone explain to me why you get the following error when using array_keys() on an object which implements the interface ArrayAccess ???
       "Warning: array_keys() expects parameter 1 to be array, object given in ... "
       If my class implements ArrayAccess, why won't array_keys() accept it ?  ( $keys=array_keys($linksToDisplay); )
    */
    $keys = array();
    foreach ($linksToDisplay as $key => $value) {
        $keys[] = $key;
    } // Stupid and ugly. Thanks php.

    // If it's a permalink, we change on-the-fly the title of the page.
    if (!empty($search_type) && $search_type == 'permalink') {
        $GLOBALS['pagetitle'] = $linksToDisplay[$keys[0]]['title'].' - '.$GLOBALS['title'];
    }

    // Select articles according to paging.
    $pagecount = ceil(count($keys) / $_SESSION['LINKS_PER_PAGE']);
    $pagecount = ($pagecount == 0 ? 1 : $pagecount);
    $page = (empty($_GET['page']) ? 1 : intval($_GET['page']));
    $page = ($page < 1 ? 1 : $page);
    $page = ($page > $pagecount ? $pagecount : $page);
    $i = ($page - 1) * $_SESSION['LINKS_PER_PAGE']; // Start index.
    $end = $i + $_SESSION['LINKS_PER_PAGE'];
    $linkDisp = array(); // Links to display
    while ($i < $end && $i < count($keys)) {
        $link = $linksToDisplay[$keys[$i]];
        if ($GLOBALS['config']['ENABLE_MARKDOWN'] === true) {
            $Parsedown = new Parsedown();
            $link['description'] = $Parsedown->setMarkupEscaped(true)->setBreaksEnabled(true)->text($link['description']);
        } else {
            $link['description'] = nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))));
        }
        $title = $link['title'];
        $classLi = $i % 2 != 0 ? '' : 'publicLinkHightLight';
        $link['class'] = ($link['private'] == 0 ? $classLi : 'private');
        $link['localdate'] = linkdate2locale($link['linkdate']);
        $taglist = explode(' ', $link['tags']);
        uasort($taglist, 'strcasecmp');
        $link['taglist'] = $taglist;
        if (!empty($link['via'])) {
            $link['via'] = htmlspecialchars($link['via']);
        }
        $linkDisp[$keys[$i]] = $link;
        ++$i;
    }

    // Compute paging navigation
    $searchterm = (empty($_GET['searchterm']) ? '' : '&searchterm='.$_GET['searchterm']);
    $searchtags = (empty($_GET['searchtags']) ? '' : '&searchtags='.$_GET['searchtags']);
    $paging = '';
    $previous_page_url = '';
    if ($i != count($keys)) {
        $previous_page_url = '?page='.($page + 1).$searchterm.$searchtags;
    }
    $next_page_url = '';
    if ($page > 1) {
        $next_page_url = '?page='.($page - 1).$searchterm.$searchtags;
    }

    $token = '';
    if (isLoggedIn()) {
        $token = getToken();
    }

    // Fill all template fields.
    $PAGE->assign('linkcount', count($LINKSDB));
    $PAGE->assign('previous_page_url', $previous_page_url);
    $PAGE->assign('next_page_url', $next_page_url);
    $PAGE->assign('page_current', $page);
    $PAGE->assign('page_max', $pagecount);
    if (!empty($GLOBALS['pagetitle']) && count($linkDisp) == 1) {
        $PAGE->assign('pagetitle', $GLOBALS['pagetitle']);
    }
    $PAGE->assign('result_count', count($linksToDisplay));
    $PAGE->assign('search_type', $search_type);
    $PAGE->assign('search_crits', $search_crits);
    $PAGE->assign('redirector', empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector']); // optional redirector URL
    $PAGE->assign('token', $token);
    $PAGE->assign('links', $linkDisp);

    return;
}

// Compute the thumbnail for a link.
//
// with a link to the original URL.
// Understands various services (youtube.com...)
// Input: $url = url for which the thumbnail must be found.
//        $href = if provided, this URL will be followed instead of $url
// Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
// Some of them may be missing.
// Return an empty array if no thumbnail available.
function computeThumbnail($url, $href = false)
{
    if (!$GLOBALS['config']['ENABLE_THUMBNAILS']) {
        return array();
    }
    if ($href == false) {
        $href = $url;
    }

    // For most hosts, the URL of the thumbnail can be easily deduced from the URL of the link.
    // (eg. http://www.youtube.com/watch?v=spVypYk4kto --->  http://img.youtube.com/vi/spVypYk4kto/default.jpg )
    //                                     ^^^^^^^^^^^                                 ^^^^^^^^^^^
    $domain = parse_url($url, PHP_URL_HOST);
    if ($domain == 'youtube.com' || $domain == 'www.youtube.com') {
        parse_str(parse_url($url, PHP_URL_QUERY), $params); // Extract video ID and get thumbnail
        if (!empty($params['v'])) {
            return array('src' => 'https://img.youtube.com/vi/'.$params['v'].'/default.jpg',
                                               'href' => $href, 'width' => '120', 'height' => '90', 'alt' => 'YouTube thumbnail', );
        }
    }
    if ($domain == 'youtu.be') {
        // Youtube short links

        $path = parse_url($url, PHP_URL_PATH);

        return array('src' => 'https://img.youtube.com/vi'.$path.'/default.jpg',
                     'href' => $href, 'width' => '120', 'height' => '90', 'alt' => 'YouTube thumbnail', );
    }
    if ($domain == 'pix.toile-libre.org') {
        // pix.toile-libre.org image hosting

        parse_str(parse_url($url, PHP_URL_QUERY), $params); // Extract image filename.
        if (!empty($params) && !empty($params['img'])) {
            return array('src' => 'http://pix.toile-libre.org/upload/thumb/'.urlencode($params['img']),
                                                                    'href' => $href, 'style' => 'max-width:120px; max-height:150px', 'alt' => 'pix.toile-libre.org thumbnail', );
        }
    }

    if ($domain == 'imgur.com') {
        $path = parse_url($url, PHP_URL_PATH);
        if (startsWith($path, '/a/') && empty($GLOBALS['config']['externalThumbshot'])) {
            return array(); // Thumbnails for albums are not available.
        }
        if (startsWith($path, '/r/')) {
            return array('src' => 'https://i.imgur.com/'.basename($path).'s.jpg',
                                                  'href' => $href, 'width' => '90', 'height' => '90', 'alt' => 'imgur.com thumbnail', );
        }
        if (startsWith($path, '/gallery/')) {
            return array('src' => 'https://i.imgur.com'.substr($path, 8).'s.jpg',
                                                        'href' => $href, 'width' => '90', 'height' => '90', 'alt' => 'imgur.com thumbnail', );
        }

        if (substr_count($path, '/') == 1) {
            return array('src' => 'https://i.imgur.com/'.substr($path, 1).'s.jpg',
                                                     'href' => $href, 'width' => '90', 'height' => '90', 'alt' => 'imgur.com thumbnail', );
        }
    }
    if ($domain == 'i.imgur.com') {
        $pi = pathinfo(parse_url($url, PHP_URL_PATH));
        if (!empty($pi['filename'])) {
            return array('src' => 'https://i.imgur.com/'.$pi['filename'].'s.jpg',
                                                  'href' => $href, 'width' => '90', 'height' => '90', 'alt' => 'imgur.com thumbnail', );
        }
    }
    if ($domain == 'dailymotion.com' || $domain == 'www.dailymotion.com') {
        if (strpos($url, 'dailymotion.com/video/') !== false) {
            $thumburl = str_replace('dailymotion.com/video/', 'dailymotion.com/thumbnail/video/', $url);

            return array('src' => $thumburl,
                         'href' => $href, 'width' => '120', 'style' => 'height:auto;', 'alt' => 'DailyMotion thumbnail', );
        }
    }
    if (endsWith($domain, '.imageshack.us')) {
        $ext = strtolower(pathinfo($url, PATHINFO_EXTENSION));
        if ($ext == 'jpg' || $ext == 'jpeg' || $ext == 'png' || $ext == 'gif') {
            $thumburl = substr($url, 0, strlen($url) - strlen($ext)).'th.'.$ext;

            return array('src' => $thumburl,
                         'href' => $href, 'width' => '120', 'style' => 'height:auto;', 'alt' => 'imageshack.us thumbnail', );
        }
    }
    if (!empty($GLOBALS['config']['externalThumbshot']) && $GLOBALS['config']['ENABLE_THUMBNAILS'] !== false) {
        if (strlen($url) <= 7) {
            $url = serverUrl().'/'.$url;
        }
        $thumburl = $GLOBALS['config']['externalThumbshot'].urlencode($url);

        return array('src' => $thumburl, 'href' => $href, 'width' => '120', 'style' => 'height:auto;', 'alt' => 'Custom Thumbshot');
    }

    // Some other hosts are SLOW AS HELL and usually require an extra HTTP request to get the thumbnail URL.
    // So we deport the thumbnail generation in order not to slow down page generation
    // (and we also cache the thumbnail)

    if (!$GLOBALS['config']['ENABLE_LOCALCACHE']) {
        return array();
    } // If local cache is disabled, no thumbnails for services which require the use a local cache.

    if ($domain == 'flickr.com' || endsWith($domain, '.flickr.com')
        || $domain == 'vimeo.com'
        || $domain == 'ted.com' || endsWith($domain, '.ted.com')
        || $domain == 'xkcd.com' || endsWith($domain, '.xkcd.com')
    ) {
        if ($domain == 'vimeo.com') {   // Make sure this vimeo url points to a video (/xxx... where xxx is numeric)
            $path = parse_url($url, PHP_URL_PATH);
            if (!preg_match('!/\d+.+?!', $path)) {
                return array();
            } // This is not a single video URL.
        }
        if ($domain == 'xkcd.com' || endsWith($domain, '.xkcd.com')) {   // Make sure this url points to a single comic (/xxx... where xxx is numeric)
            $path = parse_url($url, PHP_URL_PATH);
            if (!preg_match('!/\d+.+?!', $path)) {
                return array();
            }
        }
        if ($domain == 'ted.com' || endsWith($domain, '.ted.com')) {   // Make sure this TED url points to a video (/talks/...)
            $path = parse_url($url, PHP_URL_PATH);
            if ('/talks/' !== substr($path, 0, 7)) {
                return array();
            } // This is not a single video URL.
        }
        $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
        return array('src' => indexUrl().'?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.rawurlencode($url),
                     'href' => $href, 'width' => '120', 'style' => 'height:auto;', 'alt' => 'thumbnail', );
    }

    // For all other, we try to make a thumbnail of links ending with .jpg/jpeg/png/gif
    // Technically speaking, we should download ALL links and check their Content-Type to see if they are images.
    // But using the extension will do.
    $ext = strtolower(pathinfo($url, PATHINFO_EXTENSION));
    if ($ext == 'jpg' || $ext == 'jpeg' || $ext == 'png' || $ext == 'gif') {
        $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
        return array('src' => indexUrl().'?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.urlencode($url),
                     'href' => $href, 'width' => '120', 'style' => 'height:auto;', 'alt' => 'thumbnail', );
    }

    return array(); // No thumbnail.
}

// Returns the HTML code to display a thumbnail for a link
// with a link to the original URL.
// Understands various services (youtube.com...)
// Input: $url = url for which the thumbnail must be found.
//        $href = if provided, this URL will be followed instead of $url
// Returns '' if no thumbnail available.
function thumbnail($url, $href = false)
{
    $t = computeThumbnail($url, $href);
    if (count($t) == 0) {
        return '';
    } // Empty array = no thumbnail for this URL.

    $html = '<a href="'.htmlspecialchars($t['href']).'"><img src="'.htmlspecialchars($t['src']).'"';
    if (!empty($t['width'])) {
        $html .= ' width="'.htmlspecialchars($t['width']).'"';
    }
    if (!empty($t['height'])) {
        $html .= ' height="'.htmlspecialchars($t['height']).'"';
    }
    if (!empty($t['style'])) {
        $html .= ' style="'.htmlspecialchars($t['style']).'"';
    }
    if (!empty($t['alt'])) {
        $html .= ' alt="'.htmlspecialchars($t['alt']).'"';
    }
    $html .= '></a>';

    return $html;
}

// Returns the HTML code to display a thumbnail for a link
// for the picture wall (using lazy image loading)
// Understands various services (youtube.com...)
// Input: $url = url for which the thumbnail must be found.
//        $href = if provided, this URL will be followed instead of $url
// Returns '' if no thumbnail available.
function lazyThumbnail($url, $href = false)
{
    $t = computeThumbnail($url, $href);
    if (count($t) == 0) {
        return '';
    } // Empty array = no thumbnail for this URL.

    $html = '<a href="'.htmlspecialchars($t['href']).'">';

    // Lazy image (only loaded by javascript when in the viewport).
    if (!empty($GLOBALS['disablejquery'])) { // (except if jQuery is disabled)
        $html .= '<img class="lazyimage" src="'.htmlspecialchars($t['src']).'"';
    } else {
        $html .= '<img class="b-lazy" src="#" data-original="'.htmlspecialchars($t['src']).'" data-src="'.htmlspecialchars($t['src']).'"';
    }

    if (!empty($t['width'])) {
        $html .= ' width="'.htmlspecialchars($t['width']).'"';
    }
    if (!empty($t['height'])) {
        $html .= ' height="'.htmlspecialchars($t['height']).'"';
    }
    if (!empty($t['style'])) {
        $html .= ' style="'.htmlspecialchars($t['style']).'"';
    }
    if (!empty($t['alt'])) {
        $html .= ' alt="'.htmlspecialchars($t['alt']).'"';
    }
    $html .= '>';

    // No-javascript fallback.
    $html .= '<noscript><img src="'.htmlspecialchars($t['src']).'"';
    if (!empty($t['width'])) {
        $html .= ' width="'.htmlspecialchars($t['width']).'"';
    }
    if (!empty($t['height'])) {
        $html .= ' height="'.htmlspecialchars($t['height']).'"';
    }
    if (!empty($t['style'])) {
        $html .= ' style="'.htmlspecialchars($t['style']).'"';
    }
    if (!empty($t['alt'])) {
        $html .= ' alt="'.htmlspecialchars($t['alt']).'"';
    }
    $html .= '></noscript></a>';

    return $html;
}

function returnFavicon($url)
{
    if (!$GLOBALS['config']['ENABLE_FAVICON']) {
        return;
    }
    $faviconHash = md5($url);
    $path = substr($faviconHash, 0, 2).'/'.substr($faviconHash, 2, 2);
    $faviconPath = $GLOBALS['config']['CACHEDIR'].'/'.$path.'/'.$faviconHash.'.ico';
    if ($GLOBALS['config']['ENABLE_LOCALCACHE'] === true && file_exists($faviconPath)) {
        $content = file_get_contents($faviconPath);

        return '<img class="favicon" alt="favicon" src="data:image/ico;base64,'.base64_encode($content).'"/>';
    }
    if (file_exists($GLOBALS['config']['CACHEDIR'].'/'.$path.'/'.$faviconHash)) {
        return;
    }
    require_once 'inc/DataAccess.php';
    require_once 'inc/Favicon.php';
    $favicon = new \Favicon\Favicon();
    $favicon->cache(array('dir' => 'cache'));
    $urlOfFavicon = $favicon->get($url);
    if (!$urlOfFavicon) {
        if ($GLOBALS['config']['ENABLE_LOCALCACHE'] === true) {
            mkdir($GLOBALS['config']['CACHEDIR'].'/'.$path, 0777, true);
            touch($GLOBALS['config']['CACHEDIR'].'/'.$path.'/'.$faviconHash);

            return;
        } else {
            return;
        }
    }
    if ($GLOBALS['config']['ENABLE_LOCALCACHE'] === true && !is_dir($GLOBALS['config']['CACHEDIR'].'/'.$path.'/')) {
        mkdir($GLOBALS['config']['CACHEDIR'].'/'.$path, 0777, true);
    }
    $content = file_get_contents($urlOfFavicon);
    if ($GLOBALS['config']['ENABLE_LOCALCACHE'] === true) {
        file_put_contents($faviconPath, $content);
    }

    return '<img  class="favicon" alt="favicon" src="data:image/ico;base64,'.base64_encode($content).'"/>';
}

// -----------------------------------------------------------------------------------------------
// Installation
// This function should NEVER be called if the file data/config.php exists.
function install()
{
    // On free.fr host, make sure the /sessions directory exists, otherwise login will not work.
    if (endsWith($_SERVER['HTTP_HOST'], '.free.fr') && !is_dir($_SERVER['DOCUMENT_ROOT'].'/sessions')) {
        mkdir($_SERVER['DOCUMENT_ROOT'].'/sessions', 0705);
    }

    // This part makes sure sessions works correctly.
    // (Because on some hosts, session.save_path may not be set correctly,
    // or we may not have write access to it.)
    if (isset($_GET['test_session']) && (!isset($_SESSION) || !isset($_SESSION['session_tested']) || $_SESSION['session_tested'] != 'Working')) {   // Step 2: Check if data in session is correct.
        echo '<pre>Sessions do not seem to work correctly on your server.<br>';
        echo 'Make sure the variable session.save_path is set correctly in your php config, and that you have write access to it.<br>';
        echo 'It currently points to '.session_save_path().'<br><br><a href="?">Click to try again.</a></pre>';
        die;
    }
    if (!isset($_SESSION['session_tested'])) {   // Step 1 : Try to store data in session and reload page.
        $_SESSION['session_tested'] = 'Working';  // Try to set a variable in session.
        header('Location: '.indexUrl().'?test_session');  // Redirect to check stored data.
    }
    if (isset($_GET['test_session'])) {   // Step 3: Sessions are ok. Remove test parameter from URL.
        header('Location: '.indexUrl());
    }

    if (!empty($_POST['setlogin']) && !empty($_POST['setpassword'])) {
        $tz = 'UTC';
        if (!empty($_POST['continent']) && !empty($_POST['city'])) {
            if (isTZvalid($_POST['continent'], $_POST['city'])) {
                $tz = $_POST['continent'].'/'.$_POST['city'];
            }
        }
        $GLOBALS['timezone'] = $tz;
        // Everything is ok, let's create config file.
        $GLOBALS['login'] = $_POST['setlogin'];
        $GLOBALS['salt'] = sha1(uniqid('', true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
        $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
        $GLOBALS['title'] = (empty($_POST['title']) ? 'Shared links on '.htmlspecialchars(indexUrl()) : $_POST['title']);
        $GLOBALS['config']['ENABLE_UPDATECHECK'] = !empty($_POST['updateCheck']);
        writeConfig();
        echo '<script>alert("Shaarli is now configured. Please enter your login/password and start shaaring your links !");document.location=\'?do=login\';</script>';
        exit;
    }

    // Display config form:
    list($timezone_form, $timezone_js) = templateTZform();
    $timezone_html = '';
    if ($timezone_form != '') {
        $timezone_html = '<tr><td valign="top"><b>Timezone:</b></td><td>'.$timezone_form.'</td></tr>';
    }

    $PAGE = new pageBuilder();
    $PAGE->assign('timezone_html', $timezone_html);
    $PAGE->assign('timezone_js', $timezone_js);
    $PAGE->renderPage('install');
    exit;
}

// Generates the timezone selection form and javascript.
// Input: (optional) current timezone (can be 'UTC/UTC'). It will be pre-selected.
// Output: array(html,js)
// Example: list($htmlform,$js) = templateTZform('Europe/Paris');  // Europe/Paris pre-selected.
// Returns array('','') if server does not support timezones list. (eg. php 5.1 on free.fr)
function templateTZform($ptz = false)
{
    if (function_exists('timezone_identifiers_list')) {
        // because of old php version (5.1) which can be found on free.fr

        // Try to split the provided timezone.
        if ($ptz == false) {
            $l = timezone_identifiers_list();
            $ptz = $l[0];
        }
        $spos = strpos($ptz, '/');
        $pcontinent = substr($ptz, 0, $spos);
        $pcity = substr($ptz, $spos + 1);
        // Display config form:
        $timezone_form = '';
        $timezone_js = '';
        // The list is in the forme "Europe/Paris", "America/Argentina/Buenos_Aires"...
        // We split the list in continents/cities.
        $continents = array();
        $cities = array();
        foreach (timezone_identifiers_list() as $tz) {
            if ($tz == 'UTC') {
                $tz = 'UTC/UTC';
            }
            $spos = strpos($tz, '/');
            if ($spos !== false) {
                $continent = substr($tz, 0, $spos);
                $city = substr($tz, $spos + 1);
                $continents[$continent] = 1;
                if (!isset($cities[$continent])) {
                    $cities[$continent] = '';
                }
                $cities[$continent] .= '<option value="'.$city.'"'.($pcity == $city ? 'selected' : '').'>'.$city.'</option>';
            }
        }
        $continents_html = '';
        $continents = array_keys($continents);
        foreach ($continents as $continent) {
            $continents_html .= '<option  value="'.$continent.'"'.($pcontinent == $continent ? 'selected' : '').'>'.$continent.'</option>';
        }
        $cities_html = $cities[$pcontinent];
        $timezone_form = "Continent: <select name=\"continent\" id=\"continent\" onChange=\"onChangecontinent();\">${continents_html}</select>";
        $timezone_form .= "&nbsp;&nbsp;&nbsp;&nbsp;City: <select name=\"city\" id=\"city\">${cities[$pcontinent]}</select><br />";
        $timezone_js = '<script>';
        $timezone_js .= 'function onChangecontinent(){document.getElementById("city").innerHTML = citiescontinent[document.getElementById("continent").value];}';
        $timezone_js .= 'var citiescontinent = '.json_encode($cities).';';
        $timezone_js .= '</script>';

        return array($timezone_form, $timezone_js);
    }

    return array('', '');
}
// Tells if a timezone is valid or not.
// If not valid, returns false.
// If system does not support timezone list, returns false.
function isTZvalid($continent, $city)
{
    $tz = $continent.'/'.$city;
    if (function_exists('timezone_identifiers_list')) {
        // because of old php version (5.1) which can be found on free.fr

        if (in_array($tz, timezone_identifiers_list())) { // it's a valid timezone ?
                    return true;
        }
    }

    return false;
}

// Webservices (for use with jQuery/jQueryUI)
// eg.  index.php?ws=tags&term=minecr
function processWS()
{
    if (empty($_GET['ws']) || empty($_GET['term'])) {
        return;
    }
    $term = $_GET['term'];
    $LINKSDB = new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
    header('Content-Type: application/json; charset=utf-8');
    // Search in tags (case insentitive, cumulative search)
    if ($_GET['ws'] == 'tags') {
        $tags = explode(' ', str_replace(',', ' ', $term));
        $last = array_pop($tags); // Get the last term ("a b c d" ==> "a b c", "d")
        $addtags = '';
        if ($tags) {
            $addtags = implode(' ', $tags).' ';
        } // We will pre-pend previous tags
        $suggested = array();
        /* To speed up things, we store list of tags in session */
        if (empty($_SESSION['tags'])) {
            $_SESSION['tags'] = $LINKSDB->allTags();
        }
        foreach ($_SESSION['tags'] as $key => $value) {
            if (startsWith($key, $last, $case = false) && !in_array($key, $tags)) {
                $suggested[$addtags.$key.' '] = 0;
            }
        }
        echo json_encode(array_keys($suggested));
        exit;
    }
    // Search a single tag (case sentitive, single tag search)
    if ($_GET['ws'] == 'singletag') {
        /* To speed up things, we store list of tags in session */
        if (empty($_SESSION['tags'])) {
            $_SESSION['tags'] = $LINKSDB->allTags();
        }
        foreach ($_SESSION['tags'] as $key => $value) {
            if (startsWith($key, $term, $case = true)) {
                $suggested[$key] = 0;
            }
        }
        echo json_encode(array_keys($suggested));
        exit;
    }
}
function getAllTheme()
{
    $allTheme = glob('tpl/*', GLOB_ONLYDIR);
    foreach ($allTheme as $value) {
        $themes[] = str_replace('tpl/', '', $value);
    }

    return $themes;
}
// Re-write configuration file according to globals.
// Requires some $GLOBALS to be set (login,hash,salt,title).
// If the config file cannot be saved, an error message is dislayed and the user is redirected to "Tools" menu.
// (otherwise, the function simply returns.)
function writeConfig()
{
    if (is_file($GLOBALS['config']['CONFIG_FILE']) && !isLoggedIn()) {
        die('You are not authorized to alter config.');
    } // Only logged in user can alter config.
    $config = "<?php\n";
    $config .= '$GLOBALS[\'login\']='.var_export($GLOBALS['login'], true).';'."\n";
    $config .= '$GLOBALS[\'hash\'] = '.var_export($GLOBALS['hash'], true).';'."\n";
    $config .= '$GLOBALS[\'salt\']='.var_export($GLOBALS['salt'], true).';'."\n";
    $config .= '$GLOBALS[\'timezone\'] = '.var_export($GLOBALS['timezone'], true).';'."\n";
    $config .= 'date_default_timezone_set('.var_export($GLOBALS['timezone'], true).');'."\n";
    $config .= '$GLOBALS[\'title\']='.var_export($GLOBALS['title'], true).';'."\n";
    $config .= '$GLOBALS[\'titleLink\'] = '.var_export($GLOBALS['titleLink'], true).';'."\n";
    $config .= '$GLOBALS[\'redirector\'] = '.var_export($GLOBALS['redirector'], true).';'."\n";
    $config .= '$GLOBALS[\'disablesessionprotection\'] = '.var_export($GLOBALS['disablesessionprotection'], true).';'."\n";
    $config .= '$GLOBALS[\'disablejquery\'] = '.var_export($GLOBALS['disablejquery'], true).';'."\n";
    $config .= '$GLOBALS[\'privateLinkByDefault\'] = '.var_export($GLOBALS['privateLinkByDefault'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_RSS_PERMALINKS\'] = '.var_export($GLOBALS['config']['ENABLE_RSS_PERMALINKS'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_UPDATECHECK\'] = '.var_export($GLOBALS['config']['ENABLE_UPDATECHECK'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_MARKDOWN\'] = '.var_export($GLOBALS['config']['ENABLE_MARKDOWN'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'BAN_AFTER\'] = '.var_export($GLOBALS['config']['BAN_AFTER'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'BAN_DURATION\'] = '.var_export($GLOBALS['config']['BAN_DURATION'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'THEME\'] = '.var_export($GLOBALS['config']['THEME'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'LINKS_PER_PAGE\'] = '.var_export($GLOBALS['config']['LINKS_PER_PAGE'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'HIDE_TIMESTAMPS\'] = '.var_export($GLOBALS['config']['HIDE_TIMESTAMPS'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_THUMBNAILS\'] = '.var_export($GLOBALS['config']['ENABLE_THUMBNAILS'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_FAVICON\'] = '.var_export($GLOBALS['config']['ENABLE_FAVICON'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'ENABLE_LOCALCACHE\'] = '.var_export($GLOBALS['config']['ENABLE_LOCALCACHE'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'externalThumbshot\'] = '.var_export($GLOBALS['config']['externalThumbshot'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'contactLink\'] = '.var_export($GLOBALS['config']['contactLink'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'DATE_FORMAT\'] = '.var_export($GLOBALS['config']['DATE_FORMAT'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'WALLABAG_URL\'] = '.var_export($GLOBALS['config']['WALLABAG_URL'], true).';'."\n";
    $config .= '$GLOBALS[\'config\'][\'WALLABAG_VERSION\'] = '.var_export($GLOBALS['config']['WALLABAG_VERSION'], true).';'."\n";
    if (!file_put_contents($GLOBALS['config']['CONFIG_FILE'],$config) || strcmp(file_get_contents($GLOBALS['config']['CONFIG_FILE']),$config)!=0)
    {
        echo '<script>alert("Shaarli could not create the config file. Please make sure Shaarli has the right to write in the folder is it installed in.");document.location=\'?\';</script>';
        exit;
    }
}

/* Because some f*cking services like flickr require an extra HTTP request to get the thumbnail URL,
   I have deported the thumbnail URL code generation here, otherwise this would slow down page generation.
   The following function takes the URL a link (eg. a flickr page) and return the proper thumbnail.
   This function is called by passing the url:
   http://mywebsite.com/shaarli/?do=genthumbnail&hmac=[HMAC]&url=[URL]
   [URL] is the URL of the link (eg. a flickr page)
   [HMAC] is the signature for the [URL] (so that these URL cannot be forged).
   The function below will fetch the image from the webservice and store it in the cache.
*/
function genThumbnail()
{
    // Make sure the parameters in the URL were generated by us.
    $sign = hash_hmac('sha256', $_GET['url'], $GLOBALS['salt']);
    if ($sign != $_GET['hmac']) {
        die('Naughty boy !');
    }

    // Let's see if we don't already have the image for this URL in the cache.
    $thumbname = hash('sha1', $_GET['url']).'.jpg';
    if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$thumbname)) {   // We have the thumbnail, just serve it:
        header('Content-Type: image/jpeg');
        echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname);

        return;
    }
    // We may also serve a blank image (if service did not respond)
    $blankname = hash('sha1', $_GET['url']).'.gif';
    if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$blankname)) {
        header('Content-Type: image/gif');
        echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname);

        return;
    }

    // Otherwise, generate the thumbnail.
    $url = $_GET['url'];
    $domain = parse_url($url, PHP_URL_HOST);

    if ($domain == 'flickr.com' || endsWith($domain, '.flickr.com')) {
        // Crude replacement to handle new Flickr domain policy (They prefer www. now)
        $url = str_replace('http://flickr.com/', 'http://www.flickr.com/', $url);

        // Is this a link to an image, or to a flickr page ?
        $imageurl = '';
        if (endswith(parse_url($url, PHP_URL_PATH), '.jpg')) {  // This is a direct link to an image. eg. http://farm1.staticflickr.com/5/5921913_ac83ed27bd_o.jpg
            preg_match('!(http://farm\d+\.staticflickr\.com/\d+/\d+_\w+_)\w.jpg!', $url, $matches);
            if (!empty($matches[1])) {
                $imageurl = $matches[1].'m.jpg';
            }
        } else {
            // this is a flickr page (html)

            list($httpstatus, $headers, $data) = getHTTP($url, 20); // Get the flickr html page.
            if (strpos($httpstatus, '200 OK') !== false) {
                // Flickr now nicely provides the URL of the thumbnail in each flickr page.
                preg_match('!<link rel=\"image_src\" href=\"(.+?)\"!', $data, $matches);
                if (!empty($matches[1])) {
                    $imageurl = $matches[1];
                }

                // In albums (and some other pages), the link rel="image_src" is not provided,
                // but flickr provides:
                // <meta property="og:image" content="http://farm4.staticflickr.com/3398/3239339068_25d13535ff_z.jpg" />
                if ($imageurl == '') {
                    preg_match('!<meta property=\"og:image\" content=\"(.+?)\"!', $data, $matches);
                    if (!empty($matches[1])) {
                        $imageurl = $matches[1];
                    }
                }
            }
        }

        if ($imageurl != '') {   // Let's download the image.
            list($httpstatus, $headers, $data) = getHTTP($imageurl, 10); // Image is 240x120, so 10 seconds to download should be enough.
            if (strpos($httpstatus, '200 OK') !== false) {
                file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname, $data); // Save image to cache.
                header('Content-Type: image/jpeg');
                echo $data;

                return;
            }
        }
    } elseif ($domain == 'vimeo.com') {
        // This is more complex: we have to perform a HTTP request, then parse the result.
        // Maybe we should deport this to javascript ? Example: http://stackoverflow.com/questions/1361149/get-img-thumbnails-from-vimeo/4285098#4285098
        $vid = substr(parse_url($url, PHP_URL_PATH), 1);
        list($httpstatus, $headers, $data) = getHTTP('https://vimeo.com/api/v2/video/'.htmlspecialchars($vid).'.php', 5);
        if (strpos($httpstatus, '200 OK') !== false) {
            $t = unserialize($data);
            $imageurl = $t[0]['thumbnail_medium'];
            // Then we download the image and serve it to our client.
            list($httpstatus, $headers, $data) = getHTTP($imageurl, 10);
            if (strpos($httpstatus, '200 OK') !== false) {
                file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname, $data); // Save image to cache.
                header('Content-Type: image/jpeg');
                echo $data;

                return;
            }
        }
    } elseif ($domain == 'ted.com' || endsWith($domain, '.ted.com')) {
        // The thumbnail for TED talks is located in the <link rel="image_src" [...]> tag on that page
        // http://www.ted.com/talks/mikko_hypponen_fighting_viruses_defending_the_net.html
        // <link rel="image_src" href="http://images.ted.com/images/ted/28bced335898ba54d4441809c5b1112ffaf36781_389x292.jpg" />
        list($httpstatus, $headers, $data) = getHTTP($url, 5);
        if (strpos($httpstatus, '200 OK') !== false) {
            // Extract the link to the thumbnail
            preg_match('!link rel="image_src" href="(http://images.ted.com/images/ted/.+_\d+x\d+\.jpg)"!', $data, $matches);
            if (!empty($matches[1])) {   // Let's download the image.
                $imageurl = $matches[1];
                list($httpstatus, $headers, $data) = getHTTP($imageurl, 20); // No control on image size, so wait long enough.
                if (strpos($httpstatus, '200 OK') !== false) {
                    $filepath = $GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
                    file_put_contents($filepath, $data); // Save image to cache.
                    if (resizeImage($filepath)) {
                        header('Content-Type: image/jpeg');
                        echo file_get_contents($filepath);

                        return;
                    }
                }
            }
        }
    } elseif ($domain == 'xkcd.com' || endsWith($domain, '.xkcd.com')) {
        // There is no thumbnail available for xkcd comics, so download the whole image and resize it.
        // http://xkcd.com/327/
        // <img src="http://imgs.xkcd.com/comics/exploits_of_a_mom.png" title="<BLABLA>" alt="<BLABLA>" />
        list($httpstatus, $headers, $data) = getHTTP($url, 5);
        if (strpos($httpstatus, '200 OK') !== false) {
            // Extract the link to the thumbnail
            preg_match('!<img src="(http://imgs.xkcd.com/comics/.*)" title="[^s]!', $data, $matches);
            if (!empty($matches[1])) {   // Let's download the image.
                $imageurl = $matches[1];
                list($httpstatus, $headers, $data) = getHTTP($imageurl, 20); // No control on image size, so wait long enough.
                if (strpos($httpstatus, '200 OK') !== false) {
                    $filepath = $GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
                    file_put_contents($filepath, $data); // Save image to cache.
                    if (resizeImage($filepath)) {
                        header('Content-Type: image/jpeg');
                        echo file_get_contents($filepath);

                        return;
                    }
                }
            }
        }
    } else {
        // For all other domains, we try to download the image and make a thumbnail.
        list($httpstatus, $headers, $data) = getHTTP($url, 30);  // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
        if (strpos($httpstatus, '200 OK') !== false) {
            $filepath = $GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
            file_put_contents($filepath, $data); // Save image to cache.
            if (resizeImage($filepath)) {
                header('Content-Type: image/jpeg');
                echo file_get_contents($filepath);

                return;
            }
        }
    }

    // Otherwise, return an empty image (8x8 transparent gif)
    $blankgif = base64_decode('R0lGODlhCAAIAIAAAP///////yH5BAEKAAEALAAAAAAIAAgAAAIHjI+py+1dAAA7');
    file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname, $blankgif); // Also put something in cache so that this URL is not requested twice.
    header('Content-Type: image/gif');
    echo $blankgif;
}

// Make a thumbnail of the image (to width: 120 pixels)
// Returns true if success, false otherwise.
function resizeImage($filepath)
{
    if (!function_exists('imagecreatefromjpeg')) {
        return false;
    } // GD not present: no thumbnail possible.

    // Trick: some stupid people rename GIF as JPEG... or else.
    // So we really try to open each image type whatever the extension is.
    $header = file_get_contents($filepath, false, null, 0, 256); // Read first 256 bytes and try to sniff file type.
    $im = false;
    $i = strpos($header, 'GIF8');
    if (($i !== false) && ($i == 0)) {
        $im = imagecreatefromgif($filepath);
    } // Well this is crude, but it should be enough.
    $i = strpos($header, 'PNG');
    if (($i !== false) && ($i == 1)) {
        $im = imagecreatefrompng($filepath);
    }
    $i = strpos($header, 'JFIF');
    if ($i !== false) {
        $im = imagecreatefromjpeg($filepath);
    }
    if (!$im) {
        return false;
    }  // Unable to open image (corrupted or not an image)
    $w = imagesx($im);
    $h = imagesy($im);
    $ystart = 0;
    $yheight = $h;
    if ($h > $w) {
        $ystart = ($h / 2) - ($w / 2);
        $yheight = $w / 2;
    }
    $nw = 120;   // Desired width
    $nh = min(floor(($h * $nw) / $w), 120); // Compute new width/height, but maximum 120 pixels height.
    // Resize image:
    $im2 = imagecreatetruecolor($nw, $nh);
    imagecopyresampled($im2, $im, 0, 0, 0, $ystart, $nw, $nh, $w, $yheight);
    imageinterlace($im2, true); // For progressive JPEG.
    $tempname = $filepath.'_TEMP.jpg';
    imagejpeg($im2, $tempname, 90);
    imagedestroy($im);
    imagedestroy($im2);
    unlink($filepath);
    rename($tempname, $filepath);  // Overwrite original picture with thumbnail.
    return true;
}

// Invalidate caches when the database is changed or the user logs out.
// (eg. tags cache).
function invalidateCaches()
{
    unset($_SESSION['tags']);  // Purge cache attached to session.
    pageCache::purgeCache();   // Purge page cache shared by sessions.
}

if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=genthumbnail')) {
    genThumbnail();
    exit;
}  // Thumbnail generation/cache does not need the link database.
if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=rss')) {
    showRSS();
    exit;
}
if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=atom')) {
    showATOM();
    exit;
}
if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=dailyrss')) {
    showDailyRSS();
    exit;
}
if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'do=daily')) {
    showDaily();
    exit;
}
if (isset($_SERVER['QUERY_STRING']) && startswith($_SERVER['QUERY_STRING'], 'ws=')) {
    processWS();
    exit;
} // Webservices (for jQuery/jQueryUI)
if (!isset($_SESSION['LINKS_PER_PAGE'])) {
    $_SESSION['LINKS_PER_PAGE'] = $GLOBALS['config']['LINKS_PER_PAGE'];
}
renderPage();