X-Git-Url: https://git.immae.eu/?a=blobdiff_plain;f=index.php;h=ba3d9c3485cb3e63f84f009aa54590309d2c1446;hb=c2f6c2680330ad40f80a4cfe68388ece8dd313ec;hp=1423cafbeae3021407618db2607c4e1584720a54;hpb=44a9d860e191878058072ab872be3a8e3339d21b;p=github%2Fshaarli%2FShaarli.git

diff --git a/index.php b/index.php
index 1423cafb..ba3d9c34 100644
--- a/index.php
+++ b/index.php
@@ -1,51 +1,76 @@
 <?php
-// Shaarli 0.0.12 beta - Shaare your links...
+// Shaarli 0.0.33 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)
 // -----------------------------------------------------------------------------------------------
 // User config:
-define('DATADIR','data'); // Data subdirectory
-define('CONFIG_FILE',DATADIR.'/config.php'); // Configuration file (user login/password)
-define('DATASTORE',DATADIR.'/datastore.php'); // Data storage file.
-define('LINKS_PER_PAGE',20); // Default links per page.
-define('IPBANS_FILENAME',DATADIR.'/ipbans.php'); // File storage for failures and bans.
-define('BAN_AFTER',4);       // Ban IP after this many failures.
-define('BAN_DURATION',1800); // Ban duration for IP address after login failures (in seconds) (1800 sec. = 30 minutes)
-define('OPEN_SHAARLI',false); // If true, anyone can add/edit/delete links without having to login
-if (get_magic_quotes_gpc())
-{
-    header('Content-Type: text/plain; charset=utf-8');
-    echo "ERROR: magic_quotes_gpc is ON in your php config. This is *BAD*. You *MUST* disable it, either by changing the value in php.ini,\n";
-    echo "or by adding the following line in .htaccess: php_flag magic_quotes_gpc Off"; exit;
-}
-checkphpversion();
-
+$GLOBALS['config']['DATADIR'] = 'data'; // Data subdirectory
+$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.
+$GLOBALS['config']['CACHEDIR'] = 'cache'; // Cache directory for thumbnails for SLOW services (like flickr)
+$GLOBALS['config']['ENABLE_LOCALCACHE'] = true; // Enable Shaarli to store thumbnail in a local cache. Disable to reduce webspace usage.
+$GLOBALS['config']['PUBSUBHUB_URL'] = ''; // PubSubHubbub support. Put an empty string to disable, or put your hub url here to enable.
+                                          // Note: You must have publisher.php in the same directory as Shaarli index.php
 // -----------------------------------------------------------------------------------------------
 // Program config (touch at your own risks !)
+$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
+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');
+define('PHPPREFIX','<?php /* '); // Prefix to encapsulate data in php code.
+define('PHPSUFFIX',' */ ?>'); // Suffix to encapsulate data in php code.
+checkphpversion();
 error_reporting(E_ALL^E_WARNING);  // See all error except warnings.
 //error_reporting(-1); // See all errors (for debugging only)
-$STARTTIME = microtime(true);  // Measure page execution time.
+
+include "inc/rain.tpl.class.php"; //include Rain TPL
+raintpl::$tpl_dir = "tpl/"; // template directory
+raintpl::$cache_dir = "tmp/"; // cache directory
+
 ob_start();
+
+// Optionnal config file.
+if (is_file($GLOBALS['config']['DATADIR'].'/options.php')) require($GLOBALS['config']['DATADIR'].'/options.php');
+
+// In case stupid admin has left magic_quotes enabled in php.ini:
+if (get_magic_quotes_gpc())
+{
+    function stripslashes_deep($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: (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");
-define('shaarli_version','0.0.12 beta');
-if (!is_dir(DATADIR)) { mkdir(DATADIR,0705); chmod(DATADIR,0705); }
-if (!is_file(DATADIR.'/.htaccess')) { file_put_contents(DATADIR.'/.htaccess',"Allow from none\nDeny from all\n"); } // Protect data files.    
-if (!is_file(CONFIG_FILE)) install();
-require CONFIG_FILE;  // Read login/password hash into $GLOBALS.
-ini_set('max_input_time','60');  // High execution time in case of problematic imports/exports.
-ini_set('memory_limit', '128M');  // Try to set max upload file size and read (May not work on some hosts).
-ini_set('post_max_size', '16M');
-ini_set('upload_max_filesize', '16M');
-define('PHPPREFIX','<?php /* '); // Prefix to encapsulate data in php code.
-define('PHPSUFFIX',' */ ?>'); // Suffix to encapsulate data in php code.
+define('shaarli_version','0.0.33 beta');
+if (!is_dir($GLOBALS['config']['DATADIR'])) { mkdir($GLOBALS['config']['DATADIR'],0705); chmod($GLOBALS['config']['DATADIR'],0705); }
+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.
+}
+if (!is_file($GLOBALS['config']['CONFIG_FILE'])) install();
+require $GLOBALS['config']['CONFIG_FILE'];  // Read login/password hash into $GLOBALS.
+// Small protection against dodgy config files:
+if (empty($GLOBALS['title'])) $GLOBALS['title']='Shared links on '.htmlspecialchars(indexUrl());
+if (empty($GLOBALS['timezone'])) $GLOBALS['timezone']=date_default_timezone_get();
 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.
 $LINKSDB=false;
@@ -53,31 +78,88 @@ $LINKSDB=false;
 // Check php version
 function checkphpversion()
 {
-    $ver=phpversion();
-    if (preg_match('!(\d+)\.(\d+)\.(\d+)!',$ver,$matches)) // (because phpversion() sometimes returns strings like "5.2.4-2ubuntu5.2")
+    if (version_compare(PHP_VERSION, '5.1.0') < 0)
     {
-        list($match,$major,$minor,$release) = $matches;
-        if ($major>=5 && $minor>=1) return; // 5.1.x or higher is ok.
-        die('Your server supports php '.$ver.'. Shaarli requires at last php 5.1, and thus cannot run. Sorry.');
+        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'])<time()-($GLOBALS['config']['UPDATECHECK_INTERVAL'])))
+    {
+        $version=shaarli_version;
+        list($httpstatus,$headers,$data) = getHTTP('http://sebsauvage.net/files/shaarli_version.txt',2);
+        if (strpos($httpstatus,'200 OK')!==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
     }
-    // if cannot check php version... well, at your own risks.
+    // Compare versions:
+    $newestversion=file_get_contents($GLOBALS['config']['UPDATECHECK_FILENAME']);
+    if (version_compare($newestversion,shaarli_version)==1) return $newestversion;
+    return '';
 }
 
 // -----------------------------------------------------------------------------------------------
 // Log to text file
 function logm($message)
 {
-    if (!file_exists(DATADIR.'/log.txt')) {$logFile = fopen(DATADIR.'/log.txt','w'); }
-    else { $logFile = fopen(DATADIR.'/log.txt','a'); }
-    fwrite($logFile,strval(date('Y/m/d_H:i:s')).' - '.$_SERVER["REMOTE_ADDR"].' - '.strval($message)."\n");
-    fclose($logFile);
+    $t = strval(date('Y/m/d_H:i:s')).' - '.$_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($html)));
+}
+
+/* Returns the small hash of a string
+   eg. smallHash('20111006_131924') --> yZH23w
+   Small hashes:
+     - are unique (well, as unique as crc32, at last)
+     - are always 6 characters long.
+     - only use the following characters: a-z A-Z 0-9 - _ @
+     - are NOT cryptographically secure (they CAN be forged)
+   In Shaarli, they are used as a tinyurl-like link to individual entries.
+*/
+function smallHash($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;
 }
 
+// Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
+function text2clickable($url)
+{
+    $redir = empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'];
+    return preg_replace('!((?:https?|ftp)://\S+[[:alnum:]]/?)!si','<a href="'.$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()
-{     
+{
     $loc='en_US'; // Default if browser does not send HTTP_ACCEPT_LANGUAGE
     if (isset($_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.)
@@ -86,6 +168,23 @@ function autoLocale()
     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.
@@ -106,7 +205,7 @@ function allIPs()
 }
 
 // Check that user/password is correct.
-function check_auth($login,$password) 
+function check_auth($login,$password)
 {
     $hash = sha1($password.$login.$GLOBALS['salt']);
     if ($login==$GLOBALS['login'] && $hash==$GLOBALS['hash'])
@@ -124,41 +223,43 @@ function check_auth($login,$password)
 
 // Returns true if the user is logged in.
 function isLoggedIn()
-{ 
-    if (OPEN_SHAARLI) return true; 
-    
+{
+    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']) || $_SESSION['ip']!=allIPs() || time()>=$_SESSION['expires_on'])
     {
         logout();
         return false;
     }
-    $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT;  // User accessed a page : Update his/her session expiration date.
+    if (!empty($_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() { unset($_SESSION['uid']); unset($_SESSION['ip']); unset($_SESSION['username']);}
+function logout() { if (isset($_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(IPBANS_FILENAME)) file_put_contents(IPBANS_FILENAME, "<?php\n\$GLOBALS['IPBANS']=".var_export(array('FAILURES'=>array(),'BANS'=>array()),true).";\n?>");
-include IPBANS_FILENAME;
+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]>(BAN_AFTER-1))
+    if ($gb['FAILURES'][$ip]>($GLOBALS['config']['BAN_AFTER']-1))
     {
-        $gb['BANS'][$ip]=time()+BAN_DURATION;
+        $gb['BANS'][$ip]=time()+$GLOBALS['config']['BAN_DURATION'];
         logm('IP address banned from login');
     }
     $GLOBALS['IPBANS'] = $gb;
-    file_put_contents(IPBANS_FILENAME, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
+    file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 }
 
 // Signals a successful login. Resets failed login counter.
@@ -167,7 +268,7 @@ function ban_loginOk()
     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
     unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
     $GLOBALS['IPBANS'] = $gb;
-    file_put_contents(IPBANS_FILENAME, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
+    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.
@@ -177,11 +278,11 @@ function ban_canLogin()
     if (isset($gb['BANS'][$ip]))
     {
         // User is banned. Check if the ban has expired:
-        if ($gb['BANS'][$ip]<=time())  
+        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(IPBANS_FILENAME, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
+            file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
             return true; // Ban has expired, user can login.
         }
         return false; // User is banned.
@@ -197,18 +298,35 @@ if (isset($_POST['login']))
     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($_SESSION['longlastingsession']); // Set session cookie expiration on client side
+            session_regenerate_id(true);  // Send cookie with new expiration date to browser.
+        }
+        else // Standard session expiration (=when browser closes)
+        {
+            session_set_cookie_params(0); // 0 means "When browser closes"
+            session_regenerate_id(true);
+        }
         // Optional redirect after login:
-        if (isset($_GET['post'])) { header('Location: ?post='.urlencode($_GET['post']).(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); exit; }
-        if (isset($_POST['returnurl'])) { header('Location: '.$_POST['returnurl']); exit; }
+        if (isset($_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(); 
+        ban_loginFailed();
         echo '<script language="JavaScript">alert("Wrong login/password.");document.location=\'?do=login\';</script>'; // Redirect to login screen.
-        exit;   
+        exit;
     }
-} 
+}
 
 // ------------------------------------------------------------------------------------------
 // Misc utility functions:
@@ -218,15 +336,20 @@ if (isset($_POST['login']))
 // You can append $_SERVER['SCRIPT_NAME'] to get the current script URL.
 function serverUrl()
 {
-        $serverport = ($_SERVER["SERVER_PORT"]!='80' ? ':'.$_SERVER["SERVER_PORT"] : ''); 
+        $serverport = ($_SERVER["SERVER_PORT"]=='80' || (!empty($_SERVER['HTTPS']) && $_SERVER["SERVER_PORT"]=='443') ? '' : ':'.$_SERVER["SERVER_PORT"]);
         return 'http'.(!empty($_SERVER['HTTPS'])?'s':'').'://'.$_SERVER["SERVER_NAME"].$serverport;
 }
 
+function indexUrl()
+{
+        return serverUrl() . ($_SERVER["SCRIPT_NAME"] == '/index.php' ? '' : $_SERVER["SCRIPT_NAME"]);
+}
+
 // Convert post_max_size/upload_max_filesize (eg.'16M') parameters to bytes.
-function return_bytes($val) 
+function return_bytes($val)
 {
     $val = trim($val); $last=strtolower($val[strlen($val)-1]);
-    switch($last) 
+    switch($last)
     {
         case 'g': $val *= 1024;
         case 'm': $val *= 1024;
@@ -278,9 +401,16 @@ function linkdate2rfc822($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 chose according to locale/languages sniffed from browser headers (see autoLocale()). */
+    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.
@@ -289,13 +419,13 @@ function linkdate2locale($linkdate)
 }
 
 // Parse HTTP response headers and return an associative array.
-function http_parse_headers( $headers ) 
+function http_parse_headers_shaarli( $headers )
 {
     $res=array();
     foreach($headers as $header)
     {
         $i = strpos($header,': ');
-        if ($i)
+        if ($i!==false)
         {
             $key=substr($header,0,$i);
             $value=substr($header,$i+2,strlen($header)-$i-2);
@@ -312,7 +442,7 @@ function http_parse_headers( $headers )
                       [1] = associative array containing HTTP response headers (eg. echo getHTTP($url)[1]['Content-Type'])
                       [2] = data
     Example: list($httpstatus,$headers,$data) = getHTTP('http://sebauvage.net/');
-             if (strpos($httpstatus,'200 OK'))
+             if (strpos($httpstatus,'200 OK')!==false)
                  echo 'Data type: '.htmlspecialchars($headers['Content-Type']);
              else
                  echo 'There was an error: '.htmlspecialchars($httpstatus)
@@ -323,10 +453,10 @@ function getHTTP($url,$timeout=30)
     {
         $options = array('http'=>array('method'=>'GET','timeout' => $timeout)); // Force network timeout
         $context = stream_context_create($options);
-        $data=file_get_contents($url,false,$context,-1, 2000000); // We download at most 2 Mb from source.
+        $data=file_get_contents($url,false,$context,-1, 4000000); // We download at most 4 Mb from source.
         if (!$data) { $lasterror=error_get_last();  return array($lasterror['message'],array(),''); }
         $httpStatus=$http_response_header[0]; // eg. "HTTP/1.1 200 OK"
-        $responseHeaders=http_parse_headers($http_response_header);
+        $responseHeaders=http_parse_headers_shaarli($http_response_header);
         return array($httpStatus,$responseHeaders,$data);
     }
     catch (Exception $e)  // getHTTP *can* fail silentely (we don't care if the title cannot be fetched)
@@ -337,9 +467,9 @@ function getHTTP($url,$timeout=30)
 
 // Extract title from an HTML document.
 // (Returns an empty string if not found.)
-function html_extract_title($html) 
+function html_extract_title($html)
 {
-  return preg_match('!<title>(.*?)</title>!i', $html, $matches) ? $matches[1] : '';
+  return preg_match('!<title>(.*?)</title>!is', $html, $matches) ? trim(str_replace("\n",' ', $matches[1])) : '' ;
 }
 
 // ------------------------------------------------------------------------------------------
@@ -352,11 +482,11 @@ 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;    
+    return $rnd;
 }
 
 // Tells if a token is ok. Using this function will destroy the token.
-// true=token is ok. 
+// true=token is ok.
 function tokenOk($token)
 {
     if (isset($_SESSION['tokens'][$token]))
@@ -367,6 +497,58 @@ function tokenOk($token)
     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()
+    {    
+        global $LINKSDB;
+        $this->tpl = new RainTPL;    
+        $this->tpl->assign('newversion',checkUpdate());
+        $this->tpl->assign('linkcount',count($LINKSDB));
+        $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);
+        $this->tpl->assign('pagetitle','Shaarli');
+        if (!empty($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.
@@ -375,14 +557,13 @@ function tokenOk($token)
       echo $mylinks['20110826_161819']['title'];
       foreach($mylinks as $link)
          echo $link['title'].' at url '.$link['url'].' ; description:'.$link['description'];
-   
+
    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)
@@ -397,8 +578,8 @@ class linkdb implements Iterator, Countable, ArrayAccess
         $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); }
 
@@ -409,17 +590,17 @@ class linkdb implements Iterator, Countable, ArrayAccess
         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;    
+        $this->urls[$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]); 
+        $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
@@ -430,23 +611,24 @@ class linkdb implements Iterator, Countable, ArrayAccess
     // ---- Misc methods
     private function checkdb() // Check if db directory and file exists.
     {
-        if (!file_exists(DATASTORE)) // Create a dummy database for example.
+        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']] = $link;             
-             file_put_contents(DATASTORE, PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX); // Write database to disk
-        }    
+             $this->links[$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() 
+    private function readdb()
     {
         // Read data
-        $this->links=(file_exists(DATASTORE) ? unserialize(gzinflate(base64_decode(substr(file_get_contents(DATASTORE),strlen(PHPPREFIX),-strlen(PHPSUFFIX))))) : array() );
-        
+        $this->links=(file_exists($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)
         {
@@ -454,60 +636,79 @@ class linkdb implements Iterator, Countable, ArrayAccess
             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() 
+    // Save database from memory to disk.
+    public function savedb()
     {
         if (!$this->loggedin) die('You are not authorized to change the database.');
-        file_put_contents(DATASTORE, PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX);
+        file_put_contents($GLOBALS['config']['DATASTORE'], PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX);
     }
-    
+
     // Returns the link for a given URL (if it exists). false it does not exist.
-    public function getLinkFromUrl($url) 
+    public function getLinkFromUrl($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($mydb->filterTags('hollandais'));
-    public function filterFulltext($searchterms)  
+    // 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']),$s) || strpos(strtolower($l['description']),$s) || strpos(strtolower($l['url']),$s) || strpos(strtolower($l['tags']),$s);
+        {
+            $found=   (strpos(strtolower($l['title']),$s)!==false)
+                   || (strpos(strtolower($l['description']),$s)!==false)
+                   || (strpos(strtolower($l['url']),$s)!==false)
+                   || (strpos(strtolower($l['tags']),$s)!==false);
             if ($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($tags)
+    public function filterTags($tags,$casesensitive=false)
     {
-        $t = str_replace(',',' ',strtolower($tags));
+        $t = str_replace(',',' ',($casesensitive?$tags:strtolower($tags)));
         $searchtags=explode(' ',$t);
         $filtered=array();
         foreach($this->links as $l)
-        { 
-            $linktags = explode(' ',strtolower($l['tags']));
+        {
+            $linktags = explode(' ',($casesensitive?$l['tags']:strtolower($l['tags'])));
             if (count(array_intersect($linktags,$searchtags)) == count($searchtags))
                 $filtered[$l['linkdate']] = $l;
         }
         krsort($filtered);
         return $filtered;
-    }   
+    }
+
+    // Filter by smallHash.
+    // Only 1 article is returned.
+    public function filterSmallHash($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
@@ -516,11 +717,10 @@ class linkdb implements Iterator, Countable, ArrayAccess
         $tags=array();
         foreach($this->links as $link)
             foreach(explode(' ',$link['tags']) as $tag)
-                if (!empty($tag)) $tags[$tag]=0;
-        ksort($tags); // FIXME: sort by usage ? That would be better.
+                if (!empty($tag)) $tags[$tag]=(empty($tags[$tag]) ? 1 : $tags[$tag]+1);
+        arsort($tags); // Sort tags by usage (most used tag first)
         return $tags;
     }
-    
 }
 
 // ------------------------------------------------------------------------------------------
@@ -528,19 +728,41 @@ class linkdb implements Iterator, Countable, ArrayAccess
 function showRSS()
 {
     global $LINKSDB;
-    header('Content-Type: application/xhtml+xml; charset=utf-8');
-    $pageaddr=htmlspecialchars(serverUrl().$_SERVER["SCRIPT_NAME"]);
+
+    // 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;
+
+    header('Content-Type: application/rss+xml; charset=utf-8');
+    $pageaddr=htmlspecialchars(indexUrl());
     echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/">';
-    echo '<channel><title>Shared links on '.$pageaddr.'</title><link>'.$pageaddr.'</link>';
-    echo '<description>Shared links</description><language></language><copyright>'.$pageaddr.'</copyright>'."\n\n";
+    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;
-    $keys=array(); foreach($LINKSDB as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
+    $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
     while ($i<50 && $i<count($keys))
     {
-        $link = $LINKSDB[$keys[$i]];
+        $link = $linksToDisplay[$keys[$i]];
+        $guid = $pageaddr.'?'.smallHash($link['linkdate']);
         $rfc822date = linkdate2rfc822($link['linkdate']);
-        echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid>'.htmlspecialchars($link['url']).'</guid><link>'.htmlspecialchars($link['url']).'</link><pubDate>'.htmlspecialchars($rfc822date).'</pubDate>';
-        echo '<description><![CDATA['.htmlspecialchars($link['description']).']]></description></item>'."\n";      
+        $absurl = htmlspecialchars($link['url']);
+        if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
+        echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid>'.$guid.'</guid><link>'.$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($tag).'</category>'."\n"; }
+        }
+        echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))).']]></description>'."\n</item>\n";
         $i++;
     }
     echo '</channel></rss>';
@@ -548,49 +770,141 @@ function showRSS()
 }
 
 // ------------------------------------------------------------------------------------------
-// Render HTML page:
+// Ouput the last 50 links in ATOM format.
+function showATOM()
+{
+    global $LINKSDB;
+
+    // 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;
+
+    header('Content-Type: application/atom+xml; charset=utf-8');
+    $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 && $i<count($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><link href="'.$absurl.'" /><id>'.$guid.'</id>';
+        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $entries.='<updated>'.htmlspecialchars($iso8601date).'</updated>';
+        $entries.='<content type="html">'.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))))."</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>';
+    echo $feed;
+    exit;
+}
+
+// ------------------------------------------------------------------------------------------
+// Render HTML page (according to URL parameters and user rights)
 function renderPage()
 {
-    global $STARTTIME;
     global $LINKSDB;
-    
-    // Well... rendering the page would be 100x better with the excellent Smarty, but I don't want to tie this minimalist project to 100+ files.
-    // So I use a custom templating system.
-    
+
     // -------- Display login form.
-    if (startswith($_SERVER["QUERY_STRING"],'do=login'))
-    {
-        if (OPEN_SHAARLI) { header('Location: ?'); exit; }  // No need to login for open Shaarli
-        if (!ban_canLogin())
-        { 
-            $loginform='<div id="headerform">You have been banned from login after too many failed attempts. Try later.</div>';
-            $data = array('pageheader'=>$loginform,'body'=>'','onload'=>''); 
-            templatePage($data);
-            exit;
-        }
-        $returnurl_html = (isset($_SERVER['HTTP_REFERER']) ? '<input type="hidden" name="returnurl" value="'.htmlspecialchars($_SERVER['HTTP_REFERER']).'">' : '');        
-        $loginform='<div id="headerform"><form method="post" name="loginform">Login: <input type="text" name="login">&nbsp;&nbsp;&nbsp;Password : <input type="password" name="password"> <input type="submit" value="Login" class="bigbutton"><input type="hidden" name="token" value="'.getToken().'">'.$returnurl_html.'</form></div>';
-        $onload = 'onload="document.loginform.login.focus();"';
-        $data = array('pageheader'=>$loginform,'body'=>'','onload'=>$onload); 
-        templatePage($data);
+    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']:''));
+        $PAGE->renderPage('loginform');
         exit;
     }
-    
     // -------- User wants to logout.
-    if (startswith($_SERVER["QUERY_STRING"],'do=logout'))
-    { 
-        logout(); 
-        header('Location: ?'); 
-        exit; 
-    }    
-    
+    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);
+            $thumb=thumbnail($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;
+	    $PAGE->assign('linksToDisplay',$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;
+	    $PAGE->assign('tags',$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'].' '.urlencode($_GET['addtag'])));
+        $params['searchtags'] = (empty($params['searchtags']) ?  trim($_GET['addtag']) : trim($params['searchtags']).' '.urlencode(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($params));
         exit;
@@ -611,8 +925,8 @@ function renderPage()
         }
         header('Location: ?'.http_build_query($params));
         exit;
-    }    
-    
+    }
+
     // -------- User wants to change the number of links per page (linksperpage=...)
     if (isset($_GET['linksperpage']))
     {
@@ -620,79 +934,171 @@ function renderPage()
         header('Location: '.(empty($_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'])) 
+        if (isset($_GET['post']))
         {
-            header('Location: ?do=login&post='.urlencode($_GET['post']).(isset($_GET['source'])?'&source='.urlencode($_GET['source']):'')); // Redirect to login page, then back to post link.
+            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;
         }
-        
-        // Show search form and display list of links.
-        $searchform=<<<HTML
-<div id="headerform" style="width:100%; white-space:nowrap;";>
-    <form method="GET" name="searchform" style="display:inline;"><input type="text" name="searchterm" style="width:50%" value=""> <input type="submit" value="Search" class="bigbutton"></form>
-    <form method="GET" name="tagfilter" style="display:inline;padding-left:24px;"><input type="text" name="searchtags" style="width:20%" value=""> <input type="submit" value="Filter by tag" class="bigbutton"></form>
-</div>
-HTML;
-        $onload = 'document.searchform.searchterm.focus();';
-        $data = array('pageheader'=>$searchform,'body'=>templateLinkList(),'onload'=>$onload); 
-        templatePage($data);
-        exit; // Never remove this one !
+	    $PAGE = new pageBuilder;
+	    buildLinkList($PAGE); // Compute list of links to display
+	    $PAGE->renderPage('linklist');
+	    exit; // Never remove this one ! All operations below are reserved for logged in user.
     }
-    
+
     // -------- All other functions are reserved for the registered user:
-    
+
     // -------- Display the Tools menu if requested (import/export/bookmarklet...)
-    if (startswith($_SERVER["QUERY_STRING"],'do=tools'))
-    {
-        $pageabsaddr=serverUrl().$_SERVER["SCRIPT_NAME"]; // Why doesn't php have a built-in function for that ?
-        // The javascript code for the bookmarklet:
-        $toolbar= <<<HTML
-<div id="headerform">
-    <a href="?do=import"><b>Import</b></a> - <small>Import Netscape html bookmarks (as exported from Firefox, Chrome, Opera, delicious...)</small><br> 
-    <a href="?do=export"><b>Export</b></a> - <small>Export Netscape html bookmarks (which can be imported in Firefox, Chrome, Opera, delicious...)</small><br>
-    <a class="smallbutton" style="color:black;" onclick="alert('Drag this link to your bookmarks toolbar, or right-click it and choose Bookmark This Link...');return false;" href="javascript:javascript:(function(){var%20url%20=%20location.href;var%20title%20=%20document.title%20||%20url;window.open('{$pageabsaddr}?post='%20+%20encodeURIComponent(url)+'&amp;title='%20+%20encodeURIComponent(title)+'&amp;source=bookmarklet','_blank','menubar=no,height=400,width=608,toolbar=no,scrollbars=no,status=no');})();">Shaare link</a> - <small>Drag this link to your bookmarks toolbar (or right-click it and choose Bookmark This Link....). Then click "Shaare link" button in any page you want to share.</small>
-</div>
-HTML;
-        $data = array('pageheader'=>$toolbar,'body'=>'','onload'=>''); 
-        templatePage($data);
+    if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=tools'))
+    {
+	    $PAGE = new pageBuilder;
+	    $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 language="JavaScript">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 language="JavaScript">alert("Your password has been changed.");document.location=\'?do=tools\';</script>';
+            exit;
+        }
+        else // show the change password form.
+        {
+		    $PAGE = new pageBuilder;
+		    $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'];
+            writeConfig();
+            echo '<script language="JavaScript">alert("Configuration was saved.");document.location=\'?do=tools\';</script>';
+            exit;
+        }
+        else // Show the configuration form.
+        {
+	        $PAGE = new pageBuilder;
+            $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('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;
+            }
+            $LINKSDB->savedb(); // save to disk
+            invalidateCaches();
+            echo '<script language="JavaScript">alert("Tag was removed from '.count($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;
+            }
+            $LINKSDB->savedb(); // save to disk
+            invalidateCaches();
+            echo '<script language="JavaScript">alert("Tag was renamed in '.count($linksToAlter).' links.");document.location=\'?searchtags='.urlencode($_POST['totag']).'\';</script>';
+            exit;
+        }
+    }
+
     // -------- User wants to add a link without using the bookmarklet: show form.
-    if (startswith($_SERVER["QUERY_STRING"],'do=addlink'))
+    if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=addlink'))
     {
-        $onload = 'document.addform.post.focus();';
-        $addform= '<div id="headerform"><form method="GET" action="" name="addform"><input type="text" name="post" style="width:70%;"> <input type="submit" value="Add link" class="bigbutton"></div>';
-        $data = array('pageheader'=>$addform,'body'=>'','onload'=>$onload); 
-        templatePage($data);
+	    $PAGE = new pageBuilder;
+	    $PAGE->renderPage('addlink');
         exit;
-    }    
-    
+    }
+
     // -------- User clicked the "Save" button when editing a link: Save link to database.
     if (isset($_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']),'private'=>(isset($_POST['lf_private']) ? 1 : 0),
-                      'linkdate'=>$linkdate,'tags'=>trim($_POST['lf_tags']));        
+                      'linkdate'=>$linkdate,'tags'=>str_replace(',',' ',$tags));
         if ($link['title']=='') $link['title']=$link['url']; // If title is empty, use the URL as title.
         $LINKSDB[$linkdate] = $link;
         $LINKSDB->savedb(); // save to disk
-        
+        pubsubhub();
+        invalidateCaches();
+
         // If we are called from the bookmarklet, we must close the popup:
         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; 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($_POST['cancel_edit']))
     {
@@ -700,7 +1106,7 @@ HTML;
         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; exit; }
         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
         header('Location: '.$returnurl); // After canceling, redirect to the page the user was on.
-        exit;    
+        exit;
     }
 
     // -------- User clicked the "Delete" button when editing a link : Delete link from database.
@@ -713,84 +1119,109 @@ HTML;
         $linkdate=$_POST['lf_linkdate'];
         unset($LINKSDB[$linkdate]);
         $LINKSDB->savedb(); // save to disk
+        invalidateCaches();
         // If we are called from the bookmarklet, we must close the popup:
         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; exit; }
         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
         header('Location: '.$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($_GET['edit_link']))  
+    if (isset($_GET['edit_link']))
     {
         $link = $LINKSDB[$_GET['edit_link']];  // Read database
         if (!$link) { header('Location: ?'); exit; } // Link not found in database.
-        list($editform,$onload)=templateEditForm($link);
-        $data = array('pageheader'=>$editform,'body'=>'','onload'=>$onload); 
-        templatePage($data);    
-        exit;       
+	    $PAGE = new pageBuilder;
+	    $PAGE->assign('link',$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) $url=substr($url,0,$i);
-        $i=strpos($url,'?utm_source='); if ($i) $url=substr($url,0,$i);
-        
+        $i=strpos($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 (!$link) 
+        if (!$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).
             $description=''; $tags=''; $private=0;
-            if (parse_url($url,PHP_URL_SCHEME)=='') $url = 'http://'.$url;                
+            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')) $title=html_entity_decode(html_extract_title($data),ENT_QUOTES,'UTF-8');
+                // FIXME: Decode charset according to specified in either 1) HTTP response headers or 2) <head> in html
+                if (strpos($status,'200 OK')!==false) $title=html_entity_decode(html_extract_title($data),ENT_QUOTES,'UTF-8');
             }
-            $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'tags'=>$tags,'private'=>0); 
+            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'=>$description,'tags'=>$tags,'private'=>0);
         }
-        list($editform,$onload)=templateEditForm($link,$link_is_new); 
-        $data = array('pageheader'=>$editform,'body'=>'','onload'=>$onload); 
-        templatePage($data);    
+
+	    $PAGE = new pageBuilder;
+	    $PAGE->assign('link',$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'] : ''));
+	    $PAGE->renderPage('editlink');
         exit;
     }
-    
+
     // -------- Export as Netscape Bookmarks HTML file.
-    if (startswith($_SERVER["QUERY_STRING"],'do=export'))
-    {    
+    if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=export'))
+    {
+        if (empty($_GET['what']))
+        {
+		    $PAGE = new pageBuilder;
+		    $PAGE->renderPage('export');
+	        exit;
+        }
+        $exportWhat=$_GET['what'];
+        if (!array_intersect(array('all','public','private'),array($exportWhat))) die('What are you trying to export ???');
+
         header('Content-Type: text/html; charset=utf-8');
-        header('Content-disposition: attachment; filename=bookmarks_'.strval(date('Ymd_His')).'.html');
+        header('Content-disposition: attachment; filename=bookmarks_'.$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 $link)
         {
-            echo '<DT><A HREF="'.htmlspecialchars($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($link['description'])."\n";
+            if ($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";
+            }
         }
-        echo '<!-- Shaarli bookmarks export on '.date('Y/m/d H:i:s')."-->\n";
-        exit;
-    }            
+                exit;
+    }
 
     // -------- User is uploading a file for import
-    if (startswith($_SERVER["QUERY_STRING"],'do=upload'))
+    if (isset($_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))
@@ -798,46 +1229,28 @@ HTML;
             $returnurl = ( empty($_SERVER['HTTP_REFERER']) ? '?' : $_SERVER['HTTP_REFERER'] );
             echo '<script language="JavaScript">alert("The file you are trying to upload is probably bigger than what this webserver can accept ('.getMaxFileSize().' bytes). Please upload in smaller chunks.");document.location=\''.htmlspecialchars($returnurl).'\';</script>';
             exit;
-        }         
+        }
         if (!tokenOk($_POST['token'])) die('Wrong token.');
         importFile();
         exit;
-    }     
-    
+    }
+
     // -------- Show upload/import dialog:
-    if (startswith($_SERVER["QUERY_STRING"],'do=import'))
-    {    
-        $token = getToken();
-        $maxfilesize=getMaxFileSize();
-        $onload = 'onload="document.uploadform.filetoupload.focus();"';
-        $uploadform=<<<HTML
-<div id="headerform">
-Import Netscape html bookmarks (as exported from Firefox/Chrome/Opera/delicious/diigo...) (Max: {$maxfilesize} bytes).
-<form method="POST" action="?do=upload" enctype="multipart/form-data" name="uploadform">
-    <input type="hidden" name="token" value="{$token}">        
-    <input type="file" name="filetoupload" size="80">
-    <input type="hidden" name="MAX_FILE_SIZE" value="{$maxfilesize}">
-    <input type="submit" name="import_file" value="Import" class="bigbutton">   
-</form>
-</div>
-HTML;
-        $data = array('pageheader'=>$uploadform,'body'=>'','onload'=>$onload  ); 
-        templatePage($data);
+    if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=import'))
+    {
+	    $PAGE = new pageBuilder;
+        $PAGE->assign('token',getToken());
+        $PAGE->assign('maxfilesize',getMaxFileSize());
+	    $PAGE->renderPage('import');
         exit;
-    }    
+    }
 
     // -------- Otherwise, simply display search form and links:
-    $searchform=<<<HTML
-<div id="headerform" style="width:100%; white-space:nowrap;";>
-    <form method="GET" name="searchform" style="display:inline;"><input type="text" name="searchterm" style="width:50%" value=""> <input type="submit" value="Search" class="bigbutton"></form>
-    <form method="GET" name="tagfilter" style="display:inline;padding-left:24px;"><input type="text" name="searchtags" style="width:20%" value=""> <input type="submit" value="Filter by tag" class="bigbutton"></form>
-</div>
-HTML;
-    $onload = 'document.searchform.searchterm.focus();';
-    $data = array('pageheader'=>$searchform,'body'=>templateLinkList(),'onload'=>$onload); 
-    templatePage($data);
+    $PAGE = new pageBuilder;
+    buildLinkList($PAGE); // Compute list of links to display
+    $PAGE->renderPage('linklist');
     exit;
-}    
+}
 
 // -----------------------------------------------------------------------------------------------
 // Process the import file form.
@@ -845,291 +1258,261 @@ function importFile()
 {
     global $LINKSDB;
     $filename=$_FILES['filetoupload']['name'];
-    $filesize=$_FILES['filetoupload']['size'];    
+    $filesize=$_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.      
-        // I didn't want to use DOM... anyway, this is FAST (less than 1 second to import 7200 links (2.1 Mb html file)).
-        $before=count($LINKSDB); 
+        // 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);  
+            $link = array('linkdate'=>'','title'=>'','url'=>'','description'=>'','tags'=>'','private'=>0);
             $d = explode('<DD>',$html);
             if (startswith($d[0],'<A '))
             {
-                $link['description'] = (isset($d[1]) ? trim($d[1]) : '');  // Get description (optional)
+                $link['description'] = (isset($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') $link['url']=$value;
-                    elseif ($attr=='ADD_DATE') $link['linkdate']=date('Ymd_His',intval($value));
+                    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') $link['tags']=str_replace(',',' ',$value);
-                }     
-                if ($link['linkdate']!='' && $link['url']!='')  $LINKSDB[$link['linkdate']] = $link;
-            }     
+                    elseif ($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++;
+                        }
+                    }
+
+                }
+            }
         }
-        $import_count = count($LINKSDB)-$before;
         $LINKSDB->savedb();
-        echo '<script language="JavaScript">alert("File '.$filename.' ('.$filesize.' bytes) was successfully imported: '.$import_count.' new links.");document.location=\'?\';</script>';            
+        invalidateCaches();
+        echo '<script language="JavaScript">alert("File '.$filename.' ('.$filesize.' bytes) was successfully processed: '.$import_count.' links imported.");document.location=\'?\';</script>';
     }
     else
     {
         echo '<script language="JavaScript">alert("File '.$filename.' ('.$filesize.' bytes) has an unknown file format. Nothing was imported.");document.location=\'?\';</script>';
     }
-}    
+}
 
 // -----------------------------------------------------------------------------------------------
-/* Template for the edit link form
-    Input: $link : link to edit (assocative array item as returned by the LINKDB class)
-Output: An array : (string) : The html code of the edit link form.
-                   (string) : The proper onload to use in body.
-    Example: list($html,$onload)=templateEditForm($mylinkdb['20110805_124532']);
-             echo $html;
-*/
-function templateEditForm($link,$link_is_new=false)
+// 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)
 {
-    $url=htmlspecialchars($link['url']);
-    $title=htmlspecialchars($link['title']);
-    $tags=htmlspecialchars($link['tags']);
-    $description=htmlspecialchars($link['description']);    
-    $private = ($link['private']==0 ? '' : 'checked="yes"');   
-    
-    // Automatically focus on empty fields:
-    $onload='onload="document.linkform.lf_tags.focus();"';
-    if ($description=='') $onload='onload="document.linkform.lf_description.focus();"';
-    if ($title=='') $onload='onload="document.linkform.lf_title.focus();"';    
-    
-    // Do not show "Delete" button if this is a new link.
-    $delete_button = '<input type="submit" value="Delete" name="delete_link" class="bigbutton" style="margin-left:180px;" onClick="return confirmDeleteLink();">';
-    if ($link_is_new) $delete_button='';
-    
-    $token=getToken(); // XSRF protection. 
-    $returnurl_html = (isset($_SERVER['HTTP_REFERER']) ? '<input type="hidden" name="returnurl" value="'.htmlspecialchars($_SERVER['HTTP_REFERER']).'">' : '');
-    $editlinkform=<<<HTML
-<div id="editlinkform">
-    <form method="post" name="linkform">
-        <input type="hidden" name="lf_linkdate" value="{$link['linkdate']}">
-        <i>URL</i><br><input type="text" name="lf_url" value="{$url}" style="width:100%"><br>
-        <i>Title</i><br><input type="text" name="lf_title" value="{$title}" style="width:100%"><br>
-        <i>Description</i><br><textarea name="lf_description" rows="4" cols="25" style="width:100%">{$description}</textarea><br>
-        <i>Tags</i><br><input type="text" id="lf_tags" name="lf_tags" value="{$tags}" style="width:100%"><br>
-        <input type="checkbox" {$private} style="margin:7 0 10 0;" name="lf_private">&nbsp;<i>Private</i><br>
-        <input type="submit" value="Save" name="save_edit" class="bigbutton" style="margin-left:40px;">
-        <input type="submit" value="Cancel" name="cancel_edit" class="bigbutton" style="margin-left:40px;">
-        {$delete_button}
-        <input type="hidden" name="token" value="{$token}">
-        {$returnurl_html}
-    </form>
-</div>    
-HTML;
-    return array($editlinkform,$onload);
-}        
+    global $LINKSDB;  // Get the links database.
 
-
-// -----------------------------------------------------------------------------------------------
-// Template for the list of links.
-// Returns html code to show the list of link according to parameters passed in URL (search terms, page...)
-function templateLinkList()
-{     
-    global $LINKSDB;
-    
-    // Search according to entered search terms:
+    // ---- Filter link database according to parameters
     $linksToDisplay=array();
-    $searched='';
+    $search_type='';
+    $search_crits='';
     if (!empty($_GET['searchterm'])) // Fulltext search
     {
-        $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
-        $searched='&nbsp;<b>'.count($linksToDisplay).' results for <i>'.htmlspecialchars($_GET['searchterm']).'</i></b>:';
+        $linksToDisplay = $LINKSDB->filterFulltext(trim($_GET['searchterm']));
+        $search_crits=htmlspecialchars(trim($_GET['searchterm']));
+        $search_type='fulltext';
     }
     elseif (!empty($_GET['searchtags'])) // Search by tag
     {
-        $linksToDisplay = $LINKSDB->filterTags($_GET['searchtags']);
-        $tagshtml=''; foreach(explode(' ',$_GET['searchtags']) as $tag) $tagshtml.='<span class="linktag" title="Remove tag"><a href="?removetag='.htmlspecialchars($tag).'">'.htmlspecialchars($tag).' <span style="border-left:1px solid #aaa; padding-left:5px; color:#6767A7;">x</span></a></span> ';
-        $searched='&nbsp;<b>'.count($linksToDisplay).' results for tags '.$tagshtml.':</b>';    
+        $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));
+        $search_type='permalink';
     }
     else
         $linksToDisplay = $LINKSDB;  // otherwise, display without filtering.
-   
-    $linklist='';
-    $actions='';
-    
-    // Handle paging.
+        
+
+    // ---- 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 there is only a single link, we change on-the-fly the title of the page.
+    if (count($linksToDisplay)==1) $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'];    
+    $end = $i+$_SESSION['LINKS_PER_PAGE'];
+    $linkDisp=array(); // Links to display
     while ($i<$end && $i<count($keys))
-    {  
+    {
         $link = $linksToDisplay[$keys[$i]];
-        $description=$link['description'];
+        $link['description']=nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))));
         $title=$link['title'];
-        $classprivate = ($link['private']==0 ? '' : 'class="private"');
-        if (isLoggedIn()) $actions=' <form method="GET" class="buttoneditform"><input type="hidden" name="edit_link" value="'.$link['linkdate'].'"><input type="submit" value="Edit" class="smallbutton"></form>';
-        $tags='';
-        if ($link['tags']!='') foreach(explode(' ',$link['tags']) as $tag) { $tags.='<span class="linktag" title="Add tag"><a href="?addtag='.htmlspecialchars($tag).'">'.htmlspecialchars($tag).'</a></span> '; }
-        $linklist.='<li '.$classprivate.'><span class="linktitle"><a href="'.htmlspecialchars($link['url']).'">'.htmlspecialchars($title).'</a></span>'.$actions.'<br>';
-        if ($description!='') $linklist.='<div class="linkdescription">'.nl2br(htmlspecialchars($description)).'</div><br>';
-        $linklist.='<span class="linkdate">'.htmlspecialchars(linkdate2locale($link['linkdate'])).' - </span><span class="linkurl">'.htmlspecialchars($link['url']).'</span><br>'.$tags."</li>\n";  
+        $classLi =  $i%2!=0 ? '' : 'publicLinkHightLight';
+        $link['class'] = ($link['private']==0 ? $classLi : 'private');
+        $link['localdate']=linkdate2locale($link['linkdate']);
+        $link['taglist']=explode(' ',$link['tags']);
+        $linkDisp[$keys[$i]] = $link;
         $i++;
-    } 
+    }
     
-    // Show paging.
+    // Compute paging navigation
     $searchterm= ( empty($_GET['searchterm']) ? '' : '&searchterm='.$_GET['searchterm'] );
     $searchtags= ( empty($_GET['searchtags']) ? '' : '&searchtags='.$_GET['searchtags'] );
-    $paging=''; 
-    if ($i!=count($keys)) $paging.='<a href="?page='.($page+1).$searchterm.$searchtags.'">&#x25C4;Older</a>';
-    $paging.= '<span style="color:#fff; padding:0 20 0 20;">page '.$page.' / '.$pagecount.'</span>';
-    if ($page>1) $paging.='<a href="?page='.($page-1).$searchterm.$searchtags.'">Newer&#x25BA;</a>';
-    $linksperpage = <<<HTML
-<div style="float:right; padding-right:5px;">
-Links per page: <a href="?linksperpage=20">20</a> <a href="?linksperpage=50">50</a> <a href="?linksperpage=100">100</a>
- <form method="GET" style="display:inline;"><input type="text" name="linksperpage" size="2" style="height:15px;"></form></div>
-HTML;
-    $paging = '<div class="paging">'.$linksperpage.$paging.'</div>';
-    $linklist='<div id="linklist">'.$paging.$searched.'<ul>'.$linklist.'</ul>'.$paging.'</div>';
-    return $linklist;
+    $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.
+    $PAGE->assign('previous_page_url',$previous_page_url);
+    $PAGE->assign('next_page_url',$next_page_url);
+    $PAGE->assign('page_current',$page);
+    $PAGE->assign('page_max',$pagecount);
+    $PAGE->assign('result_count',count($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;
 }
 
-// -----------------------------------------------------------------------------------------------
-// Template for the whole page.
-/* Input: $data (associative array).
-                Keys: 'body' : body of HTML document
-                      'pageheader' : html code to show in page header (top of page)
-                      'onload' : optional onload javascript for the <body>
-*/
-function templatePage($data)
+// 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 $url
+function thumbnail($url,$href=false)
 {
-    global $STARTTIME;
-    global $LINKSDB;
-    $shaarli_version = shaarli_version;
-    $linkcount = count($LINKSDB);
-    $open='';
-    if (OPEN_SHAARLI)
+    if (!$GLOBALS['config']['ENABLE_THUMBNAILS']) return '';
+
+    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')
     {
-        $menu=' <a href="?do=tools">Tools</a> &nbsp;<a href="?do=addlink"><b>Add link</b></a>';
-        $open='Open ';
+        parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract video ID and get thumbnail
+        if (!empty($params['v'])) return '<a href="'.htmlspecialchars($href).'"><img src="http://img.youtube.com/vi/'.htmlspecialchars($params['v']).'/default.jpg" width="120" height="90"></a>';
+    }
+    if ($domain=='youtu.be') // Youtube short links
+    {
+        $path = parse_url($url,PHP_URL_PATH);
+        return '<a href="'.htmlspecialchars($href).'"><img src="http://img.youtube.com/vi'.htmlspecialchars($path).'/default.jpg" width="120" height="90"></a>';
+    }
+    if ($domain=='imgur.com')
+    {
+        $path = parse_url($url,PHP_URL_PATH);
+        if (startsWith($path,'/a/')) return ''; // Thumbnails for albums are not available.
+        if (startsWith($path,'/r/')) return '<a href="'.htmlspecialchars($href).'"><img src="http://i.imgur.com/'.htmlspecialchars(basename($path)).'s.jpg" width="90" height="90"></a>';
+        if (startsWith($path,'/gallery/')) return '<a href="'.htmlspecialchars($href).'"><img src="http://i.imgur.com'.htmlspecialchars(substr($path,8)).'s.jpg" width="90" height="90"></a>';
+        if (substr_count($path,'/')==1) return '<a href="'.htmlspecialchars($href).'"><img src="http://i.imgur.com/'.htmlspecialchars(substr($path,1)).'s.jpg" width="90" height="90"></a>';
+    }
+    if ($domain=='i.imgur.com')
+    {
+        $pi = pathinfo(parse_url($url,PHP_URL_PATH));
+        if (!empty($pi['filename'])) return '<a href="'.htmlspecialchars($href).'"><img src="http://i.imgur.com/'.htmlspecialchars($pi['filename']).'s.jpg" width="90" height="90"></a>';
+    }
+    if ($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 '<a href="'.htmlspecialchars($href).'"><img src="'.htmlspecialchars($thumburl).'" width="120" style="height:auto;"></a>';
+        }
+    }
+    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.'.$ext;
+            return '<a href="'.htmlspecialchars($href).'"><img src="'.htmlspecialchars($thumburl).'" width="120" style="height:auto;"></a>';
+        }
     }
-    else
-        $menu=(isLoggedIn() ? ' <a href="?do=logout">Logout</a> &nbsp;<a href="?do=tools">Tools</a> &nbsp;<a href="?do=addlink"><b>Add link</b></a>' : ' <a href="?do=login">Login</a>');  
-    foreach(array('pageheader','body','onload') as $k) // make sure all required fields exist (put an empty string if not).
-    {
-        if (!array_key_exists($k,$data)) $data[$k]='';
-    }
-    $jsincludes=''; $jsincludes_bottom = '';
-    if (OPEN_SHAARLI || isLoggedIn())
-    { 
-        $jsincludes='<script language="JavaScript" src="jquery.min.js"></script><script language="JavaScript" src="jquery-ui.custom.min.js"></script>'; 
-        $source = serverUrl().$_SERVER['SCRIPT_NAME'].'?ws=tags';  
-        $jsincludes_bottom = <<<JS
-<script language="JavaScript">             
-$(document).ready(function() 
-{
-    $('#lf_tags').autocomplete({source:'{$source}',minLength:0});
-});        
-</script>    
-JS;
-    }
-    $feedurl=htmlspecialchars(serverUrl().$_SERVER['SCRIPT_NAME'].'?do=rss');
-    echo <<<HTML
-<html>
-<head>
-<title>{$open}Shaarli - Let's shaare your links...</title>
-<link rel="alternate" type="application/rss+xml" href="{$feedurl}">
-{$jsincludes}
-<style type="text/css">
-<!--
-/* CSS Reset from Yahoo to cope with browsers CSS inconsistencies. */
-/*
-Copyright (c) 2010, Yahoo! Inc. All rights reserved. Code licensed under the BSD License: http://developer.yahoo.com/yui/license.html
-version: 2.8.2r1
-*/
-html{color:#000;background:#FFF;}body,div,dl,dt,dd,ul,ol,li,h1,h2,h3,h4,h5,h6,pre,code,form,fieldset,legend,input,button,textarea,p,blockquote,th,td{margin:0;padding:0;}table{border-collapse:collapse;border-spacing:0;}fieldset,img{border:0;}address,caption,cite,code,dfn,em,strong,th,var,optgroup{font-style:inherit;font-weight:inherit;}del,ins{text-decoration:none;}li{list-style:none;}caption,th{text-align:left;}h1,h2,h3,h4,h5,h6{font-size:100%;font-weight:normal;}q:before,q:after{content:'';}abbr,acronym{border:0;font-variant:normal;}sup{vertical-align:baseline;}sub{vertical-align:baseline;}legend{color:#000;}input,button,textarea,select,optgroup,option{font-family:inherit;font-size:inherit;font-style:inherit;font-weight:inherit;}input,button,textarea,select{*font-size:100%;}
 
-body { font-family: "Trebuchet MS",Verdana,Arial,Helvetica,sans-serif; font-size:10pt; background-color: #ffffff; } 
-input { border: 1px solid #aaa; background-color:#F0F0FF; padding: 2 5 2 5; -moz-box-shadow: inset 2px 2px 3px #aaaaaa; -webkit-box-shadow: inset 2px 2px 3px #aaaaaa; box-shadow: inset 2px 2px 3px #aaaaaa; } 
-textarea { border: 1px solid #aaa; background-color:#F0F0FF; padding: 2 5 2 5; -moz-box-shadow: inset 2px 2px 3px #B2B2C4; -webkit-box-shadow: inset 2px 2px 3px #B2B2C4; box-shadow: inset 2px 2px 3px #B2B2C4; } 
-/* I don't give a shit about IE. He can't understand selectors such as input[type='submit']. */
+    // 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)
 
-.bigbutton {border-style:outset;border-width:2px;padding:3px 6px;background-color:rgb(212,212,212);font-family:Tahoma,Verdana,Arial,Helvetica,sans-serif;font-size:8pt;-moz-border-radius:0.5em;border-radius:0.5em;} 
-.smallbutton {border-style:outset;border-width:2px;padding:0px 4px;background-color:rgb(212,212,212);font-family:Tahoma,Verdana,Arial,Helvetica,sans-serif;font-size:8pt;-moz-border-radius:0.5em;border-radius:0.5em;} 
-#pageheader
-{
-color:#eee;
-border-bottom: 1px solid #aaa;    
-background-color: #6A6A6A;
-background-image: -webkit-gradient(linear, left top, left bottom, from(#6A6A6A), to(#303030)); /* Saf4+, Chrome */
-background-image: -webkit-linear-gradient(top, #6A6A6A, #303030); /* Chrome 10+, Saf5.1+ */
-background-image:    -moz-linear-gradient(top, #6A6A6A, #303030); /* FF3.6 */
-background-image:     -ms-linear-gradient(top, #6A6A6A, #303030); /* IE10 */
-background-image:      -o-linear-gradient(top, #6A6A6A, #303030); /* Opera 11.10+ */
-background-image:         linear-gradient(top, #6A6A6A, #303030);
-filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#6A6A6A', EndColorStr='#303030'); /* IE6-IE9 */
-padding-bottom: 5px;
-}
-#pageheader a:link { color:#bbb; text-decoration:none;}
-#pageheader a:visited { color:#bbb; text-decoration:none;}
-#pageheader a:hover { color:#FFFFC9; text-decoration:none;}
-#pageheader a:active { color:#bbb; text-decoration:none;} 
-.paging { background-color:#777; color:#ccc; text-align:center; padding:0 0 3 0;}
-.paging a:link { color:#ccc; text-decoration:none;}
-.paging a:visited { color:#ccc;  }
-.paging a:hover {  color:#FFFFC9;  }
-.paging a:active { color:#fff;  }
-#headerform { padding:5 5 5 15;  }
-#editlinkform {  padding:5 5 5 15px; width:80%; }
-#linklist li { padding:4 10 8 20; border-bottom: 1px solid #bbb;}
-#linklist li.private { background-color: #ccc; border-left:8px solid #888; }
-.linktitle { font-size:14pt; font-weight:bold; }
-.linktitle a { text-decoration: none; color:#0000EE; }
-.linktitle a:hover { text-decoration: underline; }
-.linktitle a:visited { color:#0000BB; }
-.linkdate { font-size:8pt; color:#888; }
-.linkurl { font-size:8pt; color:#4BAA74; }
-.linkdescription { color:#000; margin-top:0px; margin-bottom:0px; font-weight:normal; }
-.linktag { font-size:9pt; color:#777; background-color:#ddd; padding:0 6 0 6; -moz-box-shadow: inset 2px 2px 3px #ffffff; -webkit-box-shadow: inset 2px 2px 3px #ffffff; box-shadow: inset 2px 2px 3px ffffff;
-border-bottom:1px solid #aaa; border-right:1px solid #aaa;  }
-.linktag a { color:#777; text-decoration:none;  }
-.buttoneditform { display:inline; }
-#footer { font-size:8pt; text-align:center; border-top:1px solid #ddd; color: #888; }
-
-/* Minimal customisation for jQuery widgets */
-.ui-autocomplete { background-color:#fff; padding-left:5px;}
-.ui-state-hover { background-color: #604dff; color:#fff; }
-
--->
-</style>
-</head>
-<body {$data['onload']}>
-<div id="pageheader"><div style="float:right; font-style:italic; color:#bbb; text-align:right; padding:0 5 0 0;">Shaare your links...<br>{$linkcount} links</div>
-    <b><i>{$open}Shaarli {$shaarli_version}</i></b> - <a href="?">Home</a>&nbsp;{$menu}&nbsp;<a href="{$feedurl}" style="padding-left:30px;">RSS Feed</a>
-{$data['pageheader']}    
-</div>
-{$data['body']}
+    if (!$GLOBALS['config']['ENABLE_LOCALCACHE']) return ''; // If local cache is disabled, no thumbnails for services which require the use a local cache.
+
+    if ($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' || $domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
+        {   // Make sure the url is of the form /xxx... where xxx is numeric
+            // For Vimeo's videos and xkcd's comics
+            $path = parse_url($url,PHP_URL_PATH);
+            if (!preg_match('!/\d+.+?!',$path)) return ''; // This is not a single video/comic URL.
+        }
+        if ($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 ''; // This is not a single video URL.
+        }
+        $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
+        return '<a href="'.htmlspecialchars($href).'"><img src="?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.urlencode($url).'" width="120" style="height:auto;"></a>';
+    }
+
+    // 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, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
+        return '<a href="'.htmlspecialchars($href).'"><img src="?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.urlencode($url).'" width="120" style="height:auto;"></a>';
+    }
+    return ''; // No thumbnail.
 
-HTML;
-    $exectime = round(microtime(true)-$STARTTIME,4);
-    echo '<div id="footer"><b><a href="http://sebsauvage.net/wiki/doku.php?id=php:shaarli">Shaarli '.shaarli_version.'</a></b> - The personal, minimalist, super-fast, no-database delicious clone. By sebsauvage.net<br>Who gives a shit that this page was generated in '.$exectime.' seconds&nbsp;?</div>';
-    if (isLoggedIn()) echo '<script language="JavaScript">function confirmDeleteLink() { var agree=confirm("Are you sure you want to delete this link ?"); if (agree) return true ; else return false ; }</script>';
-    echo $jsincludes_bottom.'</body></html>';
 }
 
 // -----------------------------------------------------------------------------------------------
@@ -1137,43 +1520,100 @@ HTML;
 // 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($_SERVER['SERVER_NAME'],'.free.fr') && !is_dir($_SERVER['DOCUMENT_ROOT'].'/sessions')) mkdir($_SERVER['DOCUMENT_ROOT'].'/sessions',0705);
+
     if (!empty($_POST['setlogin']) && !empty($_POST['setpassword']))
     {
-        $tz=(empty($_POST['settimezone']) ? 'UTC':$_POST['settimezone']);
+        $tz = 'UTC';
+        if (!empty($_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.
-        $salt=sha1(uniqid('',true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
-        $hash = sha1($_POST['setpassword'].$_POST['setlogin'].$salt);
-        $config='<?php $GLOBALS[\'login\']='.var_export($_POST['setlogin'],true).'; $GLOBALS[\'hash\']='.var_export($hash,true).'; $GLOBALS[\'salt\']='.var_export($salt,true).'; date_default_timezone_set('.var_export($tz,true).'); ?>';
-        if (!file_put_contents(CONFIG_FILE,$config) || strcmp(file_get_contents(CONFIG_FILE),$config)!=0)
+        $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()) : $_POST['title'] );
+        writeConfig();
+        echo '<script language="JavaScript">alert("Shaarli is now configured. Please enter your login/password and start shaaring your links !");document.location=\'?do=login\';</script>';
+        exit;
+    }
+
+    // Display config form:
+    list($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 $tz)
         {
-            echo '<script language="JavaScript">alert("Shaarli could not create the config file. Please make sure Shaarli has the right to write in the folder is it installed in.");document.location=\'?\';</script>';
-            exit;
+            if ($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]=array();
+                $cities[$continent].='<option value="'.$city.'"'.($pcity==$city?'selected':'').'>'.$city.'</option>';
+            }
         }
-        echo '<script language="JavaScript">alert("Shaarli is now configured. Please enter your login/password and start shaaring your links !");document.location=\'?do=login\';</script>';        
-        exit;            
-   }
-    // Display config form:
-    $timezoneselect='';
+        $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><br /><br />";
+        $timezone_form .= "City: <select name=\"city\" id=\"city\">${cities[$pcontinent]}</select><br /><br />";
+        $timezone_js = "<script language=\"JavaScript\">";
+        $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
     {
-        $timezones='';
-        foreach(timezone_identifiers_list() as $tz) $timezones.='<option value="'.htmlspecialchars($tz).'">'.htmlspecialchars($tz)."</option>\n";
-        $timezoneselect='Timezone: <select name="settimezone"><option value="" selected>(please select:)</option>'.$timezones.'</select><br><br>';
-    }
-    echo <<<HTML
-<html><title>Shaarli - Configuration</title><style type="text/css">
-body { font-family: "Trebuchet MS",Verdana,Arial,Helvetica,sans-serif; font-size:10pt; background-color: #ffffff; } 
-input { border: 1px solid #aaa; background-color:#F0F0FF; padding: 2 5 2 5; -moz-box-shadow: inset 2px 2px 3px #aaaaaa; -webkit-box-shadow: inset 2px 2px 3px #aaaaaa; box-shadow: inset 2px 2px 3px #aaaaaa; } 
-.bigbutton {border-style:outset;border-width:2px;padding:3px 6px;background-color:rgb(212,212,212);font-family:Tahoma,Verdana,Arial,Helvetica,sans-serif;font-size:8pt;-moz-border-radius:0.5em;border-radius:0.5em;} 
-</style></head><body onload="document.configform.setlogin.focus();"><h1>Shaarli - Shaare your links...</h1>It looks like it's the first time you run Shaarli. Please chose a login/password and a timezone:<br>
-<form method="POST" action="" name="configform" style="border:1px solid black; padding:10 10 10 10;">
-Login: <input type="text" name="setlogin"><br><br>Password: <input type="password" name="setpassword"><br><br>
-{$timezoneselect}
-<input type="submit" name="Save" value="Save config" class="bigbutton"></form></body></html>
-HTML;
-    exit;
+        if (in_array($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()
@@ -1183,26 +1623,280 @@ function processWS()
     global $LINKSDB;
     header('Content-Type: application/json; charset=utf-8');
 
-    // Search in tags
+    // Search in tags (case insentitive, cumulative search)
     if ($_GET['ws']=='tags')
-    { 
-        $tags=explode(' ',$term); $last = array_pop($tags); // Get the last term ("a b c d" ==> "a b c", "d")
+    {
+        $tags=explode(' ',str_replace(',',' ',$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'] = $LINKSDB->allTags(); 
+        if (empty($_SESSION['tags'])) $_SESSION['tags'] = $LINKSDB->allTags();
         foreach($_SESSION['tags'] as $key=>$value)
         {
-            if (startsWith($key,$last,$case=false)) $suggested[$addtags.$key.' ']=0;
-        }      
+            if (startsWith($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;
+    }
+}
+
+// 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.
+    if (empty($GLOBALS['redirector'])) $GLOBALS['redirector']='';
+    $config='<?php $GLOBALS[\'login\']='.var_export($GLOBALS['login'],true).'; $GLOBALS[\'hash\']='.var_export($GLOBALS['hash'],true).'; $GLOBALS[\'salt\']='.var_export($GLOBALS['salt'],true).'; ';
+    $config .='$GLOBALS[\'timezone\']='.var_export($GLOBALS['timezone'],true).'; date_default_timezone_set('.var_export($GLOBALS['timezone'],true).'); $GLOBALS[\'title\']='.var_export($GLOBALS['title'],true).';';
+    $config .= '$GLOBALS[\'redirector\']='.var_export($GLOBALS['redirector'],true).'; ';
+    $config .= ' ?>';
+    if (!file_put_contents($GLOBALS['config']['CONFIG_FILE'],$config) || strcmp(file_get_contents($GLOBALS['config']['CONFIG_FILE']),$config)!=0)
+    {
+        echo '<script language="JavaScript">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'))
+    {
+        // WTF ? I need a flickr API key to get a fucking thumbnail ? No way.
+        // I'll extract the thumbnail URL myself. First, we have to get the flickr HTML page.
+        // All images in Flickr are in the form:
+        // http://farm[farm].static.flickr.com/[server]/[id]_[secret]_[size].jpg
+        // Example: http://farm7.static.flickr.com/6205/6088513739_fc158467fe_z.jpg
+        // We want the 240x120 format, which is _m.jpg.
+        // We search for the first image in the page which does not have the _s size,
+        // when use the _m to get the thumbnail.
+
+        // 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.static.flickr.com/5/5921913_ac83ed27bd_o.jpg
+            preg_match('!(http://farm\d+.static.flickr.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($httpstatus,'200 OK')!==false)
+            {
+                preg_match('!(http://farm\d+.static.flickr.com/\d+/\d+_\w+_)[^s].jpg!',$data,$matches);
+                if (!empty($matches[1])) $imageurl=$matches[1].'m.jpg';
+            }
+        }
+        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,$data) = getHTTP('http://vimeo.com/api/v2/video/'.htmlspecialchars($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)[^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($filepath);
+                        return;
+                    }
+                }
+            }
+        }
+    }
+
+    elseif ($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($im2);
+    rename($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']);
 }
 
-$LINKSDB=new linkdb(isLoggedIn() || OPEN_SHAARLI);  // Read links from database (and filter private links if used it not logged in).
-if (startswith($_SERVER["QUERY_STRING"],'ws=')) { processWS(); exit; } // Webservices (for jQuery/jQueryUI)
-if (!isset($_SESSION['LINKS_PER_PAGE'])) $_SESSION['LINKS_PER_PAGE']=LINKS_PER_PAGE;
-if (startswith($_SERVER["QUERY_STRING"],'do=rss')) { showRSS(); exit; }
+if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=genthumbnail')) { genThumbnail(); exit; }  // Thumbnail generation/cache does not need the link database.
+$LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
+if (isset($_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'];
+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; }
 renderPage();
-?>
\ No newline at end of file
+?>