'); // Suffix to encapsulate data in php code. // Force cookie path (but do not change lifetime) $cookie=session_get_cookie_params(); session_set_cookie_params($cookie['lifetime'],dirname($_SERVER["SCRIPT_NAME"]).'/'); // Default cookie expiration and path. // PHP Settings ini_set('max_input_time','60'); // High execution time in case of problematic imports/exports. ini_set('memory_limit', '128M'); // Try to set max upload file size and read (May not work on some hosts). ini_set('post_max_size', '16M'); ini_set('upload_max_filesize', '16M'); checkphpversion(); error_reporting(E_ALL^E_WARNING); // See all error except warnings. //error_reporting(-1); // See all errors (for debugging only) include "inc/rain.tpl.class.php"; //include Rain TPL raintpl::$tpl_dir = "tpl/"; // 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', $_COOKIE); } // Prevent caching on client side or proxy: (yes, it's ugly) header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); header("Cache-Control: no-store, no-cache, must-revalidate"); header("Cache-Control: post-check=0, pre-check=0", false); header("Pragma: no-cache"); // Directories creations (Note that your web host may require differents rights than 705.) if (!is_dir($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. 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. } // Run config screen if first run: if (!is_file($GLOBALS['config']['CONFIG_FILE'])) install(); require $GLOBALS['config']['CONFIG_FILE']; // Read login/password hash into $GLOBALS. // Handling of old config file which do not have the new parameters. if (empty($GLOBALS['title'])) $GLOBALS['title']='Shared links on '.htmlspecialchars(indexUrl()); if (empty($GLOBALS['timezone'])) $GLOBALS['timezone']=date_default_timezone_get(); if (empty($GLOBALS['disablesessionprotection'])) $GLOBALS['disablesessionprotection']=false; autoLocale(); // Sniff browser language and set date format accordingly. header('Content-Type: text/html; charset=utf-8'); // We use UTF-8 for proper international characters handling. // Check php version function checkphpversion() { if (version_compare(PHP_VERSION, '5.1.0') < 0) { header('Content-Type: text/plain; charset=utf-8'); echo 'Your server supports php '.PHP_VERSION.'. Shaarli requires at last php 5.1.0, and thus cannot run. Sorry.'; exit; } } // Checks if an update is available for Shaarli. // (at most once a day, and only for registered user.) // Output: '' = no new version. // other= the available version. function checkUpdate() { if (!isLoggedIn()) return ''; // Do not check versions for visitors. // Get latest version number at most once a day. if (!is_file($GLOBALS['config']['UPDATECHECK_FILENAME']) || (filemtime($GLOBALS['config']['UPDATECHECK_FILENAME'])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 null; if (is_file($this->filename)) { return file_get_contents($this->filename); exit; } return null; } // 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 ($handle!==false) { while (($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('>','>',str_replace('<','<',nl2br($html))); } /* Returns the small hash of a string eg. smallHash('20111006_131924') --> yZH23w Small hashes: - are unique (well, as unique as crc32, at last) - are always 6 characters long. - only use the following characters: a-z A-Z 0-9 - _ @ - are NOT cryptographically secure (they CAN be forged) In Shaarli, they are used as a tinyurl-like link to individual entries. */ function smallHash($text) { $t = rtrim(base64_encode(hash('crc32',$text,true)),'='); $t = str_replace('+','-',$t); // Get rid of characters which need encoding in URLs. $t = str_replace('/','_',$t); $t = str_replace('=','@',$t); return $t; } // In a string, converts urls to clickable links. // Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722 function text2clickable($url) { $redir = empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector']; return preg_replace('!(((?:https?|ftp|file)://|apt:)\S+[[:alnum:]]/?)!si','$1',$url); } // This function inserts   where relevant so that multiple spaces are properly displayed in HTML // even in the absence of
  (This is used in description to keep text formatting)
function keepMultipleSpaces($text)
{
    return str_replace('  ','  ',$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()
{
    $loc='en_US'; // Default if browser does not send HTTP_ACCEPT_LANGUAGE
    if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) // eg. "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. Prefered language is always presented first.)
        if (preg_match('/([a-z]{2}(-[a-z]{2})?)/i',$_SERVER['HTTP_ACCEPT_LANGUAGE'],$matches)) $loc=$matches[1];
    }
    setlocale(LC_TIME,$loc);  // 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
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');
session_start();

// 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;
}

// 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.
        $_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.
        $_SESSION['username']=$login;
        $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT;  // Set session expiration.
        logm('Login successful');
        return True;
    }
    logm('Login failed for user '.$login);
    return False;
}

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

    // If 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']); unset($_SESSION['ip']); unset($_SESSION['username']);}  }


// ------------------------------------------------------------------------------------------
// 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'], "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'], "");
}

// 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'], "");
}

// 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'], "");
            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']))
        {
            $_SESSION['longlastingsession']=31536000;  // (31536000 seconds = 1 year)
            $_SESSION['expires_on']=time()+$_SESSION['longlastingsession'];  // Set session expiration on server-side.
            session_set_cookie_params($_SESSION['longlastingsession'],dirname($_SERVER["SCRIPT_NAME"]).'/'); // 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)
        {
            session_set_cookie_params(0,dirname($_SERVER["SCRIPT_NAME"]).'/'); // 0 means "When browser closes"
            session_regenerate_id(true);
        }
        // Optional redirect after login:
        if (isset($_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();
        echo ''; // 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["SERVER_NAME"].$serverport;
}

// Returns the absolute URL of current script, without the query.
// (eg. http://sebsauvage.net/links/)
function indexUrl()
{
    return serverUrl() . ($_SERVER["SCRIPT_NAME"] == '/index.php' ? '/' : $_SERVER["SCRIPT_NAME"]);
}

// 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;
    $r = sscanf($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($linkdate)
{
    return utf8_encode(strftime('%c',linkdate2timestamp($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)); // 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('!(.*?)!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());  // 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

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

    private function initialize()
    {    
        $this->tpl = new RainTPL;    
        $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',shaarli_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['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:
    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
    function rewind() { $this->keys=array_keys($this->links); rsort($this->keys); $this->position=0; } // Start over for iteration, ordered by date (latest first).
    function key() { return $this->keys[$this->position]; } // current key
    function current() { return $this->links[$this->keys[$this->position]]; } // current value
    function next() { ++$this->position; } // go to next item
    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://pastebin.com/smCEEeSn','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['snippet']),$s)!==false)
                   || (strpos(strtolower($l['url']),$s)!==false)
                   || (strpos(strtolower($l['tags']),$s)!==false)
                   || (strpos(strtolower($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 50 links in RSS 2.0 format.
function showRSS()
{
    header('Content-Type: application/rss+xml; charset=utf-8');

    // 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;

    $pageaddr=htmlspecialchars(indexUrl());
    echo '';
    echo ''.htmlspecialchars($GLOBALS['title']).''.$pageaddr.'';
    echo 'Shared linksen-en'.$pageaddr.''."\n\n";
    if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
    {
        echo '';
        echo '';
        echo '';
        echo '';
    }
    $i=0;
    $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
    while ($i<50 && $i'.htmlspecialchars($link['title']).''.$guid.''.$absurl.'';
        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) echo ''.htmlspecialchars($rfc822date)."\n";
        if ($link['tags']!='') // Adding tags to each RSS entry (as mentioned in RSS specification)
        {
            foreach(explode(' ',$link['tags']) as $tag) { echo ''.htmlspecialchars($tag).''."\n"; }
        }
        echo ''."\n\n";
        $i++;
    }
    echo '';

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

// ------------------------------------------------------------------------------------------
// Ouput the last 50 links in ATOM format.
function showATOM()
{
    header('Content-Type: application/atom+xml; charset=utf-8');

    // 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;

    $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<50 && $i'.$guid.'';
        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $entries.=''.htmlspecialchars($iso8601date).'';
        $entries.=''.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))))."\n";
        if ($link['tags']!='') // Adding tags to each ATOM entry (as mentioned in ATOM specification)
        {
            foreach(explode(' ',$link['tags']) as $tag)
                { $entries.=''."\n"; }
        }
        $entries.="\n";
        $i++;
    }
    $feed='';
    $feed.=''.htmlspecialchars($GLOBALS['title']).'';
    if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $feed.=''.htmlspecialchars($latestDate).'';
    $feed.='';
    if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
    {
        $feed.='';
        $feed.='';
        $feed.='';
    }
    $feed.=''.htmlspecialchars($pageaddr).''.htmlspecialchars($pageaddr).'';
    $feed.=''.htmlspecialchars($pageaddr).''."\n\n"; // Yes, I know I should use a real IRI (RFC3987), but the site URL will do.
    $feed.=$entries;
    $feed.='';
    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');
    $pageaddr=htmlspecialchars(indexUrl());
    echo '';
    echo 'Daily - '.htmlspecialchars($GLOBALS['title']).''.$pageaddr.'';
    echo 'Daily shared linksen-en'.$pageaddr.''."\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 ''.htmlspecialchars($GLOBALS['title'].' - '.$daydate).''.$absurl.''.$absurl.'';
        echo ''.htmlspecialchars($rfc822date)."";
        
        // 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 ''."\n\n\n";

    }    
    echo '';
    
    $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[$i-1];
        if ($ifilterDay($day);
    // We pre-format some fields for proper output.
    foreach($linksToDisplay as $key=>$link)
    {
        $linksToDisplay[$key]['taglist']=explode(' ',$link['tags']);
        $linksToDisplay[$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,$value);
        ksort($tags);
        $tagList=array();
        foreach($tags as $key=>$value)
        {
            $tagList[$key] = array('count'=>$value,'size'=>max(40*$value/$maxcount,8));
        }
        $PAGE = new pageBuilder;
        $PAGE->assign('linkcount',count($LINKSDB));
        $PAGE->assign('tags',$tagList);
        $PAGE->renderPage('tagcloud');
        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'])); }
        header('Location: '.(empty($_SERVER['HTTP_REFERER'])?'?':$_SERVER['HTTP_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
        }
        header('Location: '.(empty($_SERVER['HTTP_REFERER'])?'?':$_SERVER['HTTP_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;
        }
        $PAGE = new pageBuilder;
        buildLinkList($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 ''; 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 '';
            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;
            $GLOBALS['title']=$_POST['title'];
            $GLOBALS['redirector']=$_POST['redirector'];
            $GLOBALS['disablesessionprotection']=!empty($_POST['disablesessionprotection']);
            writeConfig();
            echo '';
            exit;
        }
        else // Show the configuration form.
        {
            $PAGE = new pageBuilder;
            $PAGE->assign('linkcount',count($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);
            $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']))
        {
            $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['fromtag']))
        {
            $needle=trim($_POST['fromtag']);
            $linksToAlter = $LINKSDB->filterTags($needle,true); // true for case-sensitive tag search.
            foreach($linksToAlter as $key=>$value)
            {
                $tags = explode(' ',trim($value['tags']));
                unset($tags[array_search($needle,$tags)]); // Remove tag.
                $value['tags']=trim(implode(' ',$tags));
                $LINKSDB[$key]=$value;
            }
            $LINKSDB->savedb(); // save to disk
            echo '';
            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 '';
            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'];
        $link = array('title'=>trim($_POST['lf_title']),'url'=>trim($_POST['lf_url']),'description'=>trim($_POST['lf_description']),'snippet'=>trim($_POST['lf_snippet']),'private'=>(isset($_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') { echo ''; exit; }
        $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
        header('Location: '.$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') { echo ''; exit; }
        $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
        header('Location: '.$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 ''; exit; }
        $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
        if ($returnurl=='?') { $returnurl = (isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '?'); }
        header('Location: '.$returnurl); // After deleting the link, redirect to the page the user was on.
        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=...)
        $i=strpos($url,'&utm_source='); if ($i!==false) $url=substr($url,0,$i);
        $i=strpos($url,'?utm_source='); if ($i!==false) $url=substr($url,0,$i);
        $i=strpos($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'));
            $title = (empty($_GET['title']) ? '' : $_GET['title'] ); // Get title if it was provided in URL (by the bookmarklet).
            $snippet = $via = '';$description=''; $tags=''; $private=0;
            if (($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)  in html
                if (strpos($status,'200 OK')!==false) $title=html_entity_decode(html_extract_title($data),ENT_QUOTES,'UTF-8');

            }
            if ($url=='') $url='?'.smallHash($linkdate); // In case of empty URL, this is just a text (with a link that point to itself)
            $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'snippet'=>$snippet,'tags'=>$tags,'via'=>$via,'private'=>0);
        }

        $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 <<



Bookmarks

Bookmarks

HTML; foreach($LINKSDB as $link) { if ($exportWhat=='all' || ($exportWhat=='private' && $link['private']!=0) || ($exportWhat=='public' && $link['private']==0)) { echo '
'.htmlspecialchars($link['title'])."\n"; if ($link['description']!='') echo '
'.htmlspecialchars($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']) ? '?' : $_SERVER['HTTP_REFERER'] ); echo ''; exit; } if (!tokenOk($_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,'')) $type='netscape'; // Netscape bookmark file (aka Firefox). // Then import the bookmarks. if ($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('
',$data) as $html) // explode is very fast { $link = array('linkdate'=>'','title'=>'','url'=>'','description'=>'','tags'=>'','private'=>0); $d = explode('
',$html); if (startswith($d[0],'(.*?)!i',$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); 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 ''; } else { echo ''; } } // ----------------------------------------------------------------------------------------------- // Template for the list of links (