- Fix bugs on unexpected IMAP connection close (#1486190, #1486270)

- Iloha's imap.inc rewritten into rcube_imap_generic class
- rcube_imap code re-formatting

1 files changed, 2242 insertions, 0 deletions

diff --git a/program/include/rcube_imap_generic.php b/program/include/rcube_imap_generic.php
new file mode 100644
index 000000000..4fd49d062
--- /dev/null
+++ b/program/include/rcube_imap_generic.php
@@ -0,0 +1,2242 @@
+<?php
+
+/*
+ +-----------------------------------------------------------------------+
+ | program/include/rcube_imap_generic.php                                |
+ |                                                                       |
+ | This file is part of the RoundCube Webmail client                     |
+ | Copyright (C) 2005-2010, RoundCube Dev. - Switzerland                 |
+ | Licensed under the GNU GPL                                            |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   Provide alternative IMAP library that doesn't rely on the standard  |
+ |   C-Client based version. This allows to function regardless          |
+ |   of whether or not the PHP build it's running on has IMAP            |
+ |   functionality built-in.                                             |
+ |                                                                       |
+ |   Based on Iloha IMAP Library. See http://ilohamail.org/ for details  |
+ |                                                                       |
+ +-----------------------------------------------------------------------+
+ | Author: Aleksander Machniak <alec@alec.pl>                            |
+ | Author: Ryo Chijiiwa <Ryo@IlohaMail.org>                              |
+ +-----------------------------------------------------------------------+
+
+ $Id$
+
+*/
+
+
+class rcube_mail_header
+{
+	public $id;
+	public $uid;
+	public $subject;
+	public $from;
+	public $to;
+	public $cc;
+	public $replyto;
+	public $in_reply_to;
+	public $date;
+	public $messageID;
+	public $size;
+	public $encoding;
+	public $charset;
+	public $ctype;
+	public $flags;
+	public $timestamp;
+	public $f;
+	public $body_structure;
+	public $internaldate;
+	public $references;
+	public $priority;
+	public $mdn_to;
+	public $mdn_sent = false;
+	public $is_draft = false;
+	public $seen = false;
+	public $deleted = false;
+	public $recent = false;
+	public $answered = false;
+	public $forwarded = false;
+	public $junk = false;
+	public $flagged = false;
+	public $has_children = false;
+	public $depth = 0;
+	public $unread_children = 0;
+	public $others = array();
+}
+
+
+class rcube_imap_generic
+{
+    public $error;
+    public $errornum;
+	public $message;
+	public $rootdir;
+	public $delimiter;
+	public $permanentflags = array();
+    public $flags = array(
+        'SEEN'     => '\\Seen',
+        'DELETED'  => '\\Deleted',
+        'RECENT'   => '\\Recent',
+        'ANSWERED' => '\\Answered',
+        'DRAFT'    => '\\Draft',
+        'FLAGGED'  => '\\Flagged',
+        'FORWARDED' => '$Forwarded',
+        'MDNSENT'  => '$MDNSent',
+        '*'        => '\\*',
+    );
+
+	private $exists;
+	private $recent;
+    private $selected;
+	private $fp;
+	private $host;
+	private $logged = false;
+	private $capability = array();
+	private $capability_readed = false;
+    private $prefs;
+
+    /**
+     * Object constructor
+     */
+    function __construct()
+    {
+    }
+              
+    private function putLine($string, $endln=true)
+    {
+        if (!$this->fp)
+            return false;
+
+		if (!empty($this->prefs['debug_mode'])) {
+    		write_log('imap', 'C: '. rtrim($string));
+	    }
+        
+        return fputs($this->fp, $string . ($endln ? "\r\n" : ''));
+    }
+
+    // $this->putLine replacement with Command Continuation Requests (RFC3501 7.5) support
+    private function putLineC($string, $endln=true)
+    {
+        if (!$this->fp)
+            return NULL;
+
+	    if ($endln)
+		    $string .= "\r\n";
+
+	    $res = 0;
+	    if ($parts = preg_split('/(\{[0-9]+\}\r\n)/m', $string, -1, PREG_SPLIT_DELIM_CAPTURE)) {
+		    for ($i=0, $cnt=count($parts); $i<$cnt; $i++) {
+			    if (preg_match('/^\{[0-9]+\}\r\n$/', $parts[$i+1])) {
+				    $bytes = $this->putLine($parts[$i].$parts[$i+1], false);
+                    if ($bytes === false)
+                        return false;
+                    $res += $bytes;
+				    $line = $this->readLine(1000);
+				    // handle error in command
+				    if ($line[0] != '+')
+					    return false;
+				    $i++;
+			    }
+			    else {
+				    $bytes = $this->putLine($parts[$i], false);
+                    if ($bytes === false)
+                        return false;
+                    $res += $bytes;
+                }
+		    }
+	    }
+
+	    return $res;
+    }
+
+    private function readLine($size=1024)
+    {
+		$line = '';
+
+	    if (!$this->fp) {
+    		return NULL;
+	    }
+    
+	    if (!$size) {
+		    $size = 1024;
+	    }
+    
+	    do {
+		    if (feof($this->fp)) {
+			    return $line ? $line : NULL;
+		    }
+		
+    		$buffer = fgets($this->fp, $size);
+
+    		if ($buffer === false) {
+                fclose($this->fp);
+                $this->fp = null;
+        		break;
+    		}
+		    if (!empty($this->prefs['debug_mode'])) {
+			    write_log('imap', 'S: '. chop($buffer));
+    		}
+            $line .= $buffer;
+	    } while ($buffer[strlen($buffer)-1] != "\n");
+
+	    return $line;
+    }
+
+    private function multLine($line, $escape=false)
+    {
+	    $line = chop($line);
+	    if (preg_match('/\{[0-9]+\}$/', $line)) {
+		    $out = '';
+        
+		    preg_match_all('/(.*)\{([0-9]+)\}$/', $line, $a);
+		    $bytes = $a[2][0];
+		    while (strlen($out) < $bytes) {
+			    $line = $this->readBytes($bytes); 
+			    if ($line === NULL)
+				    break;
+			    $out .= $line;
+		    }
+
+		    $line = $a[1][0] . '"' . ($escape ? $this->Escape($out) : $out) . '"';
+	    }
+	
+        return $line;
+    }
+
+    private function readBytes($bytes)
+    {
+	    $data = '';
+	    $len  = 0;
+	    while ($len < $bytes && !feof($this->fp))
+	    {
+		    $d = fread($this->fp, $bytes-$len);
+		    if (!empty($this->prefs['debug_mode'])) {
+			    write_log('imap', 'S: '. $d);
+            }
+            $data .= $d;
+		    $data_len = strlen($data);
+		    if ($len == $data_len) {
+    		    break; // nothing was read -> exit to avoid apache lockups
+    		}
+    		$len = $data_len;
+	    }
+	
+	    return $data;
+    }
+
+    // don't use it in loops, until you exactly know what you're doing
+    private function readReply()
+    {
+	    do {
+		    $line = trim($this->readLine(1024));
+	    } while ($line[0] == '*');
+
+	    return $line;
+    }
+
+    private function parseResult($string)
+    {
+	    $a = explode(' ', trim($string));
+	    if (count($a) >= 2) {
+		    $res = strtoupper($a[1]);
+		    if ($res == 'OK') {
+			    return 0;
+		    } else if ($res == 'NO') {
+			    return -1;
+		    } else if ($res == 'BAD') {
+			    return -2;
+		    } else if ($res == 'BYE') {
+                fclose($this->fp);
+                $this->fp = null;
+			    return -3;
+		    }
+	    }
+	    return -4;
+    }
+
+    // check if $string starts with $match (or * BYE/BAD)
+    private function startsWith($string, $match, $error=false, $nonempty=false)
+    {
+	    $len = strlen($match);
+	    if ($len == 0) {
+		    return false;
+	    }
+        if (!$this->fp) {
+            return true;
+        }
+	    if (strncmp($string, $match, $len) == 0) {
+		    return true;
+	    }
+	    if ($error && preg_match('/^\* (BYE|BAD) /i', $string, $m)) {
+            if (strtoupper($m[1]) == 'BYE') {
+                fclose($this->fp);
+                $this->fp = null;
+            }
+		    return true;
+	    }
+        if ($nonempty && !strlen($string)) {
+            return true;
+        }
+	    return false;
+    }
+
+    private function startsWithI($string, $match, $error=false, $nonempty=false)
+    {
+	    $len = strlen($match);
+	    if ($len == 0) {
+		    return false;
+	    }
+        if (!$this->fp) {
+            return true;
+        }
+	    if (strncasecmp($string, $match, $len) == 0) {
+		    return true;
+	    }
+	    if ($error && preg_match('/^\* (BYE|BAD) /i', $string, $m)) {
+            if (strtoupper($m[1]) == 'BYE') {
+                fclose($this->fp);
+                $this->fp = null;
+            }
+		    return true;
+	    }
+        if ($nonempty && !strlen($string)) {
+            return true;
+        }
+	    return false;
+    }
+
+    function getCapability($name)
+    {
+	    if (in_array($name, $this->capability)) {
+		    return true;
+	    }
+	    else if ($this->capability_readed) {
+		    return false;
+	    }
+
+	    // get capabilities (only once) because initial 
+	    // optional CAPABILITY response may differ
+	    $this->capability = array();
+
+	    if (!$this->putLine("cp01 CAPABILITY")) {
+            return false;
+        }
+	    do {
+		    $line = trim($this->readLine(1024));
+		    $a = explode(' ', $line);
+		    if ($line[0] == '*') {
+			    while (list($k, $w) = each($a)) {
+				    if ($w != '*' && $w != 'CAPABILITY')
+    					$this->capability[] = strtoupper($w);
+			    }
+		    }
+	    } while ($a[0] != 'cp01');
+	
+	    $this->capability_readed = true;
+
+	    if (in_array($name, $this->capability)) {
+		    return true;
+	    }
+
+	    return false;
+    }
+
+    function clearCapability()
+    {
+	    $this->capability = array();
+	    $this->capability_readed = false;
+    }
+
+    function authenticate($user, $pass, $encChallenge)
+    {
+        $ipad = '';
+        $opad = '';
+    
+        // initialize ipad, opad
+        for ($i=0; $i<64; $i++) {
+            $ipad .= chr(0x36);
+            $opad .= chr(0x5C);
+        }
+
+        // pad $pass so it's 64 bytes
+        $padLen = 64 - strlen($pass);
+        for ($i=0; $i<$padLen; $i++) {
+            $pass .= chr(0);
+        }
+    
+        // generate hash
+        $hash  = md5($this->xor($pass,$opad) . pack("H*", md5($this->xor($pass, $ipad) . base64_decode($encChallenge))));
+    
+        // generate reply
+        $reply = base64_encode($user . ' ' . $hash);
+    
+        // send result, get reply
+        $this->putLine($reply);
+        $line = $this->readLine(1024);
+    
+        // process result
+        $result = $this->parseResult($line);
+        if ($result == 0) {
+            $this->error    .= '';
+            $this->errornum  = 0;
+            return $this->fp;
+        }
+
+        $this->error    .= 'Authentication for ' . $user . ' failed (AUTH): "';
+        $this->error    .= htmlspecialchars($line) . '"';
+        $this->errornum  = $result;
+
+        return $result;
+    }
+
+    function login($user, $password)
+    {
+        $this->putLine('a001 LOGIN "'.$this->escape($user).'" "'.$this->escape($password).'"');
+
+        $line = $this->readReply();
+
+        // process result
+        $result = $this->parseResult($line);
+
+        if ($result == 0) {
+            $this->error    .= '';
+            $this->errornum  = 0;
+            return $this->fp;
+        }
+
+        fclose($this->fp);
+        $this->fp = false;
+    
+        $this->error    .= 'Authentication for ' . $user . ' failed (LOGIN): "';
+        $this->error    .= htmlspecialchars($line)."\"";
+        $this->errornum  = $result;
+
+        return $result;
+    }
+
+    function namespace()
+    {
+	    if (isset($this->prefs['rootdir']) && is_string($this->prefs['rootdir'])) {
+    		$this->rootdir = $this->prefs['rootdir'];
+		    return true;
+	    }
+	
+        if (!$this->getCapability('NAMESPACE')) {
+	        return false;
+	    }
+    
+	    if (!$this->putLine("ns1 NAMESPACE")) {
+            return false;
+        }
+	    do {
+		    $line = $this->readLine(1024);
+		    if ($this->startsWith($line, '* NAMESPACE')) {
+			    $i    = 0;
+			    $line = $this->unEscape($line);
+			    $data = $this->parseNamespace(substr($line,11), $i, 0, 0);
+		    }
+	    } while (!$this->startsWith($line, 'ns1', true, true));
+
+	    if (!is_array($data)) {
+	        return false;
+	    }
+
+	    $user_space_data = $data[0];
+	    if (!is_array($user_space_data)) {
+	        return false;
+	    }
+
+	    $first_userspace = $user_space_data[0];
+	    if (count($first_userspace)!=2) {
+	        return false;
+	    }
+    
+	    $this->rootdir            = $first_userspace[0];
+	    $this->delimiter          = $first_userspace[1];
+	    $this->prefs['rootdir']   = substr($this->rootdir, 0, -1);
+	    $this->prefs['delimiter'] = $this->delimiter;
+	
+	    return true;
+    }
+
+
+    /**
+     * Gets the delimiter, for example:
+     * INBOX.foo -> .
+     * INBOX/foo -> /
+     * INBOX\foo -> \
+     * 
+     * @return mixed A delimiter (string), or false. 
+     * @see connect()
+     */
+    function getHierarchyDelimiter()
+    {
+	    if ($this->delimiter) {
+    		return $this->delimiter;
+	    }
+	    if (!empty($this->prefs['delimiter'])) {
+    	    return ($this->delimiter = $this->prefs['delimiter']);
+	    }
+
+	    $delimiter = false;
+
+	    // try (LIST "" ""), should return delimiter (RFC2060 Sec 6.3.8)
+	    if (!$this->putLine('ghd LIST "" ""')) {
+	        return false;
+	    }
+    
+	    do {
+		    $line = $this->readLine(500);
+		    if ($line[0] == '*') {
+			    $line = rtrim($line);
+			    $a = rcube_explode_quoted_string(' ', $this->unEscape($line));
+			    if ($a[0] == '*') {
+			        $delimiter = str_replace('"', '', $a[count($a)-2]);
+        		}
+		    }
+	    } while (!$this->startsWith($line, 'ghd', true, true));
+
+	    if (strlen($delimiter)>0) {
+	        return $delimiter;
+	    }
+
+	    // if that fails, try namespace extension
+	    // try to fetch namespace data
+	    if (!$this->putLine("ns1 NAMESPACE")) {
+            return false;
+        }
+
+	    do {
+		    $line = $this->readLine(1024);
+		    if ($this->startsWith($line, '* NAMESPACE')) {
+			    $i = 0;
+			    $line = $this->unEscape($line);
+			    $data = $this->parseNamespace(substr($line,11), $i, 0, 0);
+		    }
+	    } while (!$this->startsWith($line, 'ns1', true, true));
+
+	    if (!is_array($data)) {
+	        return false;
+	    }
+    
+	    // extract user space data (opposed to global/shared space)
+	    $user_space_data = $data[0];
+	    if (!is_array($user_space_data)) {
+	        return false;
+	    }
+
+	    // get first element
+	    $first_userspace = $user_space_data[0];
+	    if (!is_array($first_userspace)) {
+	        return false;
+	    }
+
+	    // extract delimiter
+	    $delimiter = $first_userspace[1];	
+
+	    return $delimiter;
+    }
+
+    function connect($host, $user, $password, $options=null)
+    {
+	    // set options
+	    if (is_array($options)) {
+            $this->prefs = $options;
+        }
+        // set auth method
+        if (!empty($this->prefs['auth_method'])) {
+            $auth_method = strtoupper($this->prefs['auth_method']);
+	    } else {
+    		$auth_method = 'CHECK';
+        }
+
+	    $message = "INITIAL: $auth_method\n";
+
+	    $result = false;
+	
+	    // initialize connection
+	    $this->error    = '';
+	    $this->errornum = 0;
+	    $this->selected = '';
+	    $this->user     = $user;
+	    $this->host     = $host;
+        $this->logged   = false;
+
+	    // check input
+	    if (empty($host)) {
+		    $this->error    = "Empty host";
+		    $this->errornum = -1;
+		    return false;
+	    }
+        if (empty($user)) {
+		    $this->error    = "Empty user";
+    		$this->errornum = -1;
+	    	return false;
+	    }
+	    if (empty($password)) {
+    		$this->error    = "Empty password";
+	    	$this->errornum = -1;
+		    return false;
+	    }
+
+	    if (!$this->prefs['port']) {
+		    $this->prefs['port'] = 143;
+	    }
+	    // check for SSL
+	    if ($this->prefs['ssl_mode'] && $this->prefs['ssl_mode'] != 'tls') {
+		    $host = $this->prefs['ssl_mode'] . '://' . $host;
+	    }
+
+	    $this->fp = @fsockopen($host, $this->prefs['port'], $errno, $errstr, 10);
+	    if (!$this->fp) {
+    		$this->error    = sprintf("Could not connect to %s:%d: %s", $host, $this->prefs['port'], $errstr);
+    		$this->errornum = -2;
+		    return false;
+	    }
+
+	    stream_set_timeout($this->fp, 10);
+	    $line = trim(fgets($this->fp, 8192));
+
+	    if ($this->prefs['debug_mode'] && $line) {
+		    write_log('imap', 'S: '. $line);
+        }
+
+	    // Connected to wrong port or connection error?
+	    if (!preg_match('/^\* (OK|PREAUTH)/i', $line)) {
+		    if ($line)
+			    $this->error = sprintf("Wrong startup greeting (%s:%d): %s", $host, $this->prefs['port'], $line);
+		    else
+			    $this->error = sprintf("Empty startup greeting (%s:%d)", $host, $this->prefs['port']);
+	        $this->errornum = -2;
+	        return false;
+	    }
+
+	    // RFC3501 [7.1] optional CAPABILITY response
+	    if (preg_match('/\[CAPABILITY ([^]]+)\]/i', $line, $matches)) {
+		    $this->capability = explode(' ', strtoupper($matches[1]));
+	    }
+
+	    $this->message .= $line;
+
+	    // TLS connection
+	    if ($this->prefs['ssl_mode'] == 'tls' && $this->getCapability('STARTTLS')) {
+        	if (version_compare(PHP_VERSION, '5.1.0', '>=')) {
+               	$this->putLine("tls0 STARTTLS");
+
+			    $line = $this->readLine(4096);
+                if (!$this->startsWith($line, "tls0 OK")) {
+				    $this->error    = "Server responded to STARTTLS with: $line";
+				    $this->errornum = -2;
+                    return false;
+                }
+
+			    if (!stream_socket_enable_crypto($this->fp, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)) {
+				    $this->error    = "Unable to negotiate TLS";
+				    $this->errornum = -2;
+				    return false;
+			    }
+			
+			    // Now we're authenticated, capabilities need to be reread
+			    $this->clearCapability();
+        	}
+	    }
+
+	    $orig_method = $auth_method;
+
+	    if ($auth_method == 'CHECK') {
+		    // check for supported auth methods
+		    if ($this->getCapability('AUTH=CRAM-MD5') || $this->getCapability('AUTH=CRAM_MD5')) {
+			    $auth_method = 'AUTH';
+		    }
+		    else {
+			    // default to plain text auth
+			    $auth_method = 'PLAIN';
+		    }
+	    }
+
+	    if ($auth_method == 'AUTH') {
+		    // do CRAM-MD5 authentication
+		    $this->putLine("a000 AUTHENTICATE CRAM-MD5");
+		    $line = trim($this->readLine(1024));
+
+		    if ($line[0] == '+') {
+			    // got a challenge string, try CRAM-MD5
+			    $result = $this->authenticate($user, $password, substr($line,2));
+        		
+			    // stop if server sent BYE response
+			    if ($result == -3) {
+				    return false;
+			    }
+		    }
+		
+		    if (!is_resource($result) && $orig_method == 'CHECK') {
+			    $auth_method = 'PLAIN';
+		    }
+	    }
+		
+	    if ($auth_method == 'PLAIN') {
+		    // do plain text auth
+		    $result = $this->login($user, $password);
+	    }
+
+	    if (is_resource($result)) {
+            if ($this->prefs['force_caps']) {
+			    $this->clearCapability();
+            }
+		    $this->namespace();
+            $this->logged = true;
+		    return true;
+	    } else {
+		    return false;
+	    }
+    }
+
+    function connected()
+    {
+		return ($this->fp && $this->logged) ? true : false;
+    }
+
+    function close()
+    {
+	    if ($this->putLine("I LOGOUT")) {
+		    if (!feof($this->fp))
+			    fgets($this->fp, 1024);
+	    }
+		@fclose($this->fp);
+		$this->fp = false;
+    }
+
+    function select($mailbox)
+    {
+	    if (empty($mailbox)) {
+		    return false;
+	    }
+	    if ($this->selected == $mailbox) {
+		    return true;
+	    }
+    
+	    if ($this->putLine("sel1 SELECT \"".$this->escape($mailbox).'"')) {
+		    do {
+			    $line = chop($this->readLine(300));
+			    $a = explode(' ', $line);
+			    if (count($a) == 3) {
+				    $token = strtoupper($a[2]);
+				    if ($token == 'EXISTS') {
+					    $this->exists = (int) $a[1];
+				    }
+				    else if ($token == 'RECENT') {
+					    $this->recent = (int) $a[1];
+				    }
+			    }
+			    else if (preg_match('/\[?PERMANENTFLAGS\s+\(([^\)]+)\)\]/U', $line, $match)) {
+				    $this->permanentflags = explode(' ', $match[1]);
+			    }
+		    } while (!$this->startsWith($line, 'sel1', true, true));
+
+		    if (strcasecmp($a[1], 'OK') == 0) {
+			    $this->selected = $mailbox;
+			    return true;
+		    }
+            else {
+                $this->error = "Couldn't select $mailbox";
+            }
+	    }
+
+        return false;
+    }
+
+    function checkForRecent($mailbox)
+    {
+	    if (empty($mailbox)) {
+		    $mailbox = 'INBOX';
+	    }
+    
+	    $this->select($mailbox);
+	    if ($this->selected == $mailbox) {
+		    return $this->recent;
+	    }
+
+	    return false;
+    }
+
+    function countMessages($mailbox, $refresh = false)
+    {
+	    if ($refresh) {
+		    $this->selected = '';
+	    }
+	
+	    $this->select($mailbox);
+	    if ($this->selected == $mailbox) {
+		    return $this->exists;
+	    }
+
+        return false;
+    }
+
+    function sort($mailbox, $field, $add='', $is_uid=FALSE, $encoding = 'US-ASCII')
+    {
+	    $field = strtoupper($field);
+	    if ($field == 'INTERNALDATE') {
+	        $field = 'ARRIVAL';
+	    }
+	
+	    $fields = array('ARRIVAL' => 1,'CC' => 1,'DATE' => 1,
+            'FROM' => 1, 'SIZE' => 1, 'SUBJECT' => 1, 'TO' => 1);
+
+	    if (!$fields[$field]) {
+	        return false;
+	    }
+
+	    /*  Do "SELECT" command */
+	    if (!$this->select($mailbox)) {
+	        return false;
+	    }
+    
+	    $is_uid = $is_uid ? 'UID ' : '';
+	
+	    // message IDs
+	    if (is_array($add))
+		    $add = $this->compressMessageSet(join(',', $add));
+
+	    $command  = "s ".$is_uid."SORT ($field) $encoding ALL";
+	    $line     = $data = '';
+
+	    if (!empty($add))
+	        $command .= ' '.$add;
+
+	    if (!$this->putLineC($command)) {
+	        return false;
+	    }
+	    do {
+		    $line = chop($this->readLine());
+		    if ($this->startsWith($line, '* SORT')) {
+			    $data .= substr($line, 7);
+    		} else if (preg_match('/^[0-9 ]+$/', $line)) {
+			    $data .= $line;
+		    }
+	    } while (!$this->startsWith($line, 's ', true, true));
+	
+	    $result_code = $this->parseResult($line);
+	
+	    if ($result_code != 0) {
+            $this->error = "Sort: $line";
+            return false;
+	    }
+	
+	    return preg_split('/\s+/', $data, -1, PREG_SPLIT_NO_EMPTY);
+    }
+
+    function fetchHeaderIndex($mailbox, $message_set, $index_field='', $skip_deleted=true, $uidfetch=false)
+    {
+	    if (is_array($message_set)) {
+		    if (!($message_set = $this->compressMessageSet(join(',', $message_set))))
+			    return false;
+	    } else {
+		    list($from_idx, $to_idx) = explode(':', $message_set);
+		    if (empty($message_set) ||
+			    (isset($to_idx) && $to_idx != '*' && (int)$from_idx > (int)$to_idx)) {
+			    return false;
+		    }
+	    }
+	
+	    $index_field = empty($index_field) ? 'DATE' : strtoupper($index_field);
+	
+    	$fields_a['DATE']         = 1;
+	    $fields_a['INTERNALDATE'] = 4;
+    	$fields_a['ARRIVAL'] 	  = 4;
+	    $fields_a['FROM']         = 1;
+    	$fields_a['REPLY-TO']     = 1;
+	    $fields_a['SENDER']       = 1;
+    	$fields_a['TO']           = 1;
+	    $fields_a['CC']           = 1;
+    	$fields_a['SUBJECT']      = 1;
+	    $fields_a['UID']          = 2;
+    	$fields_a['SIZE']         = 2;
+	    $fields_a['SEEN']         = 3;
+    	$fields_a['RECENT']       = 3;
+	    $fields_a['DELETED']      = 3;
+
+    	if (!($mode = $fields_a[$index_field])) {
+	    	return false;
+	    }
+
+    	/*  Do "SELECT" command */
+	    if (!$this->select($mailbox)) {
+		    return false;
+	    }
+	
+    	// build FETCH command string
+	    $key     = 'fhi0';
+	    $cmd     = $uidfetch ? 'UID FETCH' : 'FETCH';
+	    $deleted = $skip_deleted ? ' FLAGS' : '';
+
+	    if ($mode == 1 && $index_field == 'DATE')
+		    $request = " $cmd $message_set (INTERNALDATE BODY.PEEK[HEADER.FIELDS (DATE)]$deleted)";
+	    else if ($mode == 1)
+		    $request = " $cmd $message_set (BODY.PEEK[HEADER.FIELDS ($index_field)]$deleted)";
+	    else if ($mode == 2) {
+		    if ($index_field == 'SIZE')
+			    $request = " $cmd $message_set (RFC822.SIZE$deleted)";
+		    else
+			    $request = " $cmd $message_set ($index_field$deleted)";
+	    } else if ($mode == 3)
+		    $request = " $cmd $message_set (FLAGS)";
+	    else // 4
+		    $request = " $cmd $message_set (INTERNALDATE$deleted)";
+
+	    $request = $key . $request;
+
+	    if (!$this->putLine($request)) {
+		    return false;
+        }
+
+	    $result = array();
+
+	    do {
+		    $line = chop($this->readLine(200));
+		    $line = $this->multLine($line);
+
+		    if (preg_match('/^\* ([0-9]+) FETCH/', $line, $m)) {
+            	$id     = $m[1];
+			    $flags  = NULL;
+					
+			    if ($skip_deleted && preg_match('/FLAGS \(([^)]+)\)/', $line, $matches)) {
+				    $flags = explode(' ', strtoupper($matches[1]));
+				    if (in_array('\\DELETED', $flags)) {
+					    $deleted[$id] = $id;
+					    continue;
+				    }
+			    }
+
+			    if ($mode == 1 && $index_field == 'DATE') {
+				    if (preg_match('/BODY\[HEADER\.FIELDS \("*DATE"*\)\] (.*)/', $line, $matches)) {
+					    $value = preg_replace(array('/^"*[a-z]+:/i'), '', $matches[1]);
+					    $value = trim($value);
+					    $result[$id] = $this->strToTime($value);
+				    }
+				    // non-existent/empty Date: header, use INTERNALDATE
+				    if (empty($result[$id])) {
+					    if (preg_match('/INTERNALDATE "([^"]+)"/', $line, $matches))
+						    $result[$id] = $this->strToTime($matches[1]);
+					    else
+						    $result[$id] = 0;
+				    }
+			    } else if ($mode == 1) {
+				    if (preg_match('/BODY\[HEADER\.FIELDS \("?(FROM|REPLY-TO|SENDER|TO|SUBJECT)"?\)\] (.*)/', $line, $matches)) {
+					    $value = preg_replace(array('/^"*[a-z]+:/i', '/\s+$/sm'), array('', ''), $matches[2]);
+					    $result[$id] = trim($value);
+				    } else {
+					    $result[$id] = '';
+				    }
+			    } else if ($mode == 2) {
+				    if (preg_match('/\((UID|RFC822\.SIZE) ([0-9]+)/', $line, $matches)) {
+					    $result[$id] = trim($matches[2]);
+				    } else {
+					    $result[$id] = 0;
+				    }
+			    } else if ($mode == 3) {
+				    if (!$flags && preg_match('/FLAGS \(([^)]+)\)/', $line, $matches)) {
+					    $flags = explode(' ', $matches[1]);
+				    }
+				    $result[$id] = in_array('\\'.$index_field, $flags) ? 1 : 0;
+			    } else if ($mode == 4) {
+				    if (preg_match('/INTERNALDATE "([^"]+)"/', $line, $matches)) {
+					    $result[$id] = $this->strToTime($matches[1]);
+				    } else {
+					    $result[$id] = 0;
+				    }
+			    }
+		    }
+	    } while (!$this->startsWith($line, $key, true, true));
+
+	    return $result;	
+    }
+
+    private function compressMessageSet($message_set)
+    {
+	    // given a comma delimited list of independent mid's, 
+	    // compresses by grouping sequences together
+	
+	    // if less than 255 bytes long, let's not bother
+	    if (strlen($message_set)<255) {
+	        return $message_set;
+	    }
+    
+	    // see if it's already been compress
+	    if (strpos($message_set, ':') !== false) {
+	        return $message_set;
+	    }
+    
+	    // separate, then sort
+	    $ids = explode(',', $message_set);
+	    sort($ids);
+	
+	    $result = array();
+	    $start  = $prev = $ids[0];
+
+	    foreach ($ids as $id) {
+		    $incr = $id - $prev;
+		    if ($incr > 1) {			//found a gap
+			    if ($start == $prev) {
+			        $result[] = $prev;	//push single id
+			    } else {
+			        $result[] = $start . ':' . $prev;   //push sequence as start_id:end_id
+			    }
+        		$start = $id;			//start of new sequence
+		    }
+		    $prev = $id;
+	    }
+
+	    // handle the last sequence/id
+	    if ($start==$prev) {
+	        $result[] = $prev;
+	    } else {
+    	    $result[] = $start.':'.$prev;
+	    }
+    
+	    // return as comma separated string
+	    return implode(',', $result);
+    }
+
+    function UID2ID($folder, $uid)
+    {
+	    if ($uid > 0) {
+    		$id_a = $this->search($folder, "UID $uid");
+	    	if (is_array($id_a) && count($id_a) == 1) {
+		    	return $id_a[0];
+		    }
+	    }
+	    return false;
+    }
+
+    function ID2UID($folder, $id)
+    {
+	    if (empty($id)) {
+	        return 	-1;
+	    }
+
+    	if (!$this->select($folder)) {
+            return -1;
+        }
+
+	    $result = -1;
+		if ($this->putLine("fuid FETCH $id (UID)")) {
+		    do {
+			    $line = chop($this->readLine(1024));
+				if (preg_match("/^\* $id FETCH \(UID (.*)\)/i", $line, $r)) {
+					$result = $r[1];
+				}
+			} while (!$this->startsWith($line, 'fuid', true, true));
+		}
+
+    	return $result;
+    }
+
+    function fetchUIDs($mailbox, $message_set=null)
+    {
+	    if (is_array($message_set))
+		    $message_set = join(',', $message_set);
+        else if (empty($message_set))
+		    $message_set = '1:*';
+	
+	    return $this->fetchHeaderIndex($mailbox, $message_set, 'UID', false);
+    }
+
+    function fetchHeaders($mailbox, $message_set, $uidfetch=false, $bodystr=false, $add='')
+    {
+	    $result = array();
+	
+	    if (!$this->select($mailbox)) {
+		    return false;
+	    }
+
+	    if (is_array($message_set))
+		    $message_set = join(',', $message_set);
+
+	    $message_set = $this->compressMessageSet($message_set);
+
+	    if ($add)
+		    $add = ' '.strtoupper(trim($add));
+
+	    /* FETCH uid, size, flags and headers */
+	    $key  	  = 'FH12';
+	    $request  = $key . ($uidfetch ? ' UID' : '') . " FETCH $message_set ";
+	    $request .= "(UID RFC822.SIZE FLAGS INTERNALDATE ";
+	    if ($bodystr)
+		    $request .= "BODYSTRUCTURE ";
+	    $request .= "BODY.PEEK[HEADER.FIELDS ";
+	    $request .= "(DATE FROM TO SUBJECT REPLY-TO IN-REPLY-TO CC BCC ";
+	    $request .= "CONTENT-TRANSFER-ENCODING CONTENT-TYPE MESSAGE-ID ";
+	    $request .= "REFERENCES DISPOSITION-NOTIFICATION-TO X-PRIORITY ";
+	    $request .= "X-DRAFT-INFO".$add.")])";
+
+	    if (!$this->putLine($request)) {
+		    return false;
+	    }
+	    do {
+		    $line = $this->readLine(1024);
+		    $line = $this->multLine($line);
+            
+            if (!$line)
+                break;
+            
+		    $a    = explode(' ', $line);
+
+		    if (($line[0] == '*') && ($a[2] == 'FETCH')) {
+			    $id = $a[1];
+            
+			    $result[$id]            = new rcube_mail_header;
+			    $result[$id]->id        = $id;
+			    $result[$id]->subject   = '';
+			    $result[$id]->messageID = 'mid:' . $id;
+
+			    $lines = array();
+			    $ln = 0;
+
+			    // Sample reply line:
+			    // * 321 FETCH (UID 2417 RFC822.SIZE 2730 FLAGS (\Seen)
+			    // INTERNALDATE "16-Nov-2008 21:08:46 +0100" BODYSTRUCTURE (...)
+			    // BODY[HEADER.FIELDS ...
+
+			    if (preg_match('/^\* [0-9]+ FETCH \((.*) BODY/s', $line, $matches)) {
+				    $str = $matches[1];
+
+				    // swap parents with quotes, then explode
+				    $str = preg_replace('/[()]/', '"', $str);
+				    $a = rcube_explode_quoted_string(' ', $str);
+
+				    // did we get the right number of replies?
+				    $parts_count = count($a);
+				    if ($parts_count>=6) {
+					    for ($i=0; $i<$parts_count; $i=$i+2) {
+						    if ($a[$i] == 'UID')
+							    $result[$id]->uid = $a[$i+1];
+						    else if ($a[$i] == 'RFC822.SIZE')
+							    $result[$id]->size = $a[$i+1];
+    						else if ($a[$i] == 'INTERNALDATE')
+	    						$time_str = $a[$i+1];
+		    				else if ($a[$i] == 'FLAGS')
+			    				$flags_str = $a[$i+1];
+				    	}
+
+					    $time_str = str_replace('"', '', $time_str);
+					
+					    // if time is gmt...
+		                $time_str = str_replace('GMT','+0000',$time_str);
+					
+					    $result[$id]->internaldate = $time_str;
+    					$result[$id]->timestamp = $this->StrToTime($time_str);
+	    				$result[$id]->date = $time_str;
+		    		}
+
+			    	// BODYSTRUCTURE 
+				    if($bodystr) {
+					    while (!preg_match('/ BODYSTRUCTURE (.*) BODY\[HEADER.FIELDS/s', $line, $m)) {
+						    $line2 = $this->readLine(1024);
+    						$line .= $this->multLine($line2, true);
+	    				}
+		    			$result[$id]->body_structure = $m[1];
+			    	}
+
+    				// the rest of the result
+	    			preg_match('/ BODY\[HEADER.FIELDS \(.*?\)\]\s*(.*)$/s', $line, $m);
+		    		$reslines = explode("\n", trim($m[1], '"'));
+			    	// re-parse (see below)
+				    foreach ($reslines as $resln) {
+		    			if (ord($resln[0])<=32) {
+			    			$lines[$ln] .= (empty($lines[$ln])?'':"\n").trim($resln);
+				    	} else {
+					    	$lines[++$ln] = trim($resln);
+					    }
+    				}
+	    		}
+
+				// Start parsing headers.  The problem is, some header "lines" take up multiple lines.
+				// So, we'll read ahead, and if the one we're reading now is a valid header, we'll
+				// process the previous line.  Otherwise, we'll keep adding the strings until we come
+				// to the next valid header line.
+	
+			    do {
+				    $line = chop($this->readLine(300), "\r\n");
+
+    				// The preg_match below works around communigate imap, which outputs " UID <number>)".
+	    			// Without this, the while statement continues on and gets the "FH0 OK completed" message.
+		    		// If this loop gets the ending message, then the outer loop does not receive it from radline on line 1249.  
+			    	// This in causes the if statement on line 1278 to never be true, which causes the headers to end up missing
+				    // If the if statement was changed to pick up the fh0 from this loop, then it causes the outer loop to spin
+    				// An alternative might be:
+	    			// if (!preg_match("/:/",$line) && preg_match("/\)$/",$line)) break;
+		    		// however, unsure how well this would work with all imap clients.
+			    	if (preg_match("/^\s*UID [0-9]+\)$/", $line)) {
+				        break;
+				    }
+
+    				// handle FLAGS reply after headers (AOL, Zimbra?)
+	    			if (preg_match('/\s+FLAGS \((.*)\)\)$/', $line, $matches)) {
+		    			$flags_str = $matches[1];
+			    		break;
+				    }
+
+    				if (ord($line[0])<=32) {
+	    				$lines[$ln] .= (empty($lines[$ln])?'':"\n").trim($line);
+		    		} else {
+			    		$lines[++$ln] = trim($line);
+				    }
+    			// patch from "Maksim Rubis" <siburny@hotmail.com>
+	    		} while ($line[0] != ')' && !$this->startsWith($line, $key, true));
+
+    			if (strncmp($line, $key, strlen($key))) { 
+	    			// process header, fill rcube_mail_header obj.
+		    		// initialize
+			    	if (is_array($headers)) {
+				    	reset($headers);
+					    while (list($k, $bar) = each($headers)) {
+    						$headers[$k] = '';
+	    				}
+		    		}
+
+			    	// create array with header field:data
+    				while ( list($lines_key, $str) = each($lines) ) {
+	    				list($field, $string) = $this->splitHeaderLine($str);
+		    			
+			    		$field  = strtolower($field);
+				    	$string = preg_replace('/\n\s*/', ' ', $string);
+					    
+    					switch ($field) {
+	        			case 'date';
+			    			$result[$id]->date = $string;
+				    		$result[$id]->timestamp = $this->strToTime($string);
+		    		    	break;
+    					case 'from':
+	    					$result[$id]->from = $string;
+		    				break;
+			    		case 'to':
+				    		$result[$id]->to = preg_replace('/undisclosed-recipients:[;,]*/', '', $string);
+					    	break;
+    					case 'subject':
+	    					$result[$id]->subject = $string;
+		    				break;
+			    		case 'reply-to':
+				    		$result[$id]->replyto = $string;
+					    	break;
+    					case 'cc':
+	    					$result[$id]->cc = $string;
+		    				break;
+    					case 'bcc':
+	    					$result[$id]->bcc = $string;
+		    				break;
+			    		case 'content-transfer-encoding':
+				    		$result[$id]->encoding = $string;
+					    	break;
+    					case 'content-type':
+	    					$ctype_parts = preg_split('/[; ]/', $string);
+		    				$result[$id]->ctype = array_shift($ctype_parts);
+			    			if (preg_match('/charset\s*=\s*"?([a-z0-9\-\.\_]+)"?/i', $string, $regs)) {
+				    			$result[$id]->charset = $regs[1];
+					    	}
+        					break;
+					    case 'in-reply-to':
+			    			$result[$id]->in_reply_to = preg_replace('/[\n<>]/', '', $string);
+				    		break;
+    					case 'references':
+	    					$result[$id]->references = $string;
+		    				break;
+			    		case 'return-receipt-to':
+				    	case 'disposition-notification-to':
+					    case 'x-confirm-reading-to':
+    						$result[$id]->mdn_to = $string;
+	    					break;
+		    			case 'message-id':
+			    			$result[$id]->messageID = $string;
+				    		break;
+					    case 'x-priority':
+    						if (preg_match('/^(\d+)/', $string, $matches))
+	    						$result[$id]->priority = intval($matches[1]);
+		    				break;
+			    		default:
+				    		if (strlen($field) > 2)
+					    		$result[$id]->others[$field] = $string;
+						    break;
+    					} // end switch ()
+	    			} // end while ()
+		    	} else {
+			    	$a = explode(' ', $line);
+			    }
+
+    			// process flags
+	    		if (!empty($flags_str)) {
+		    		$flags_str = preg_replace('/[\\\"]/', '', $flags_str);
+			    	$flags_a   = explode(' ', $flags_str);
+					
+				    if (is_array($flags_a)) {
+    				//	reset($flags_a);
+	    				foreach($flags_a as $flag) {
+		    				$flag = strtoupper($flag);
+			    			if ($flag == 'SEEN') {
+				    		    $result[$id]->seen = true;
+					    	} else if ($flag == 'DELETED') {
+    						    $result[$id]->deleted = true;
+	    					} else if ($flag == 'RECENT') {
+		    				    $result[$id]->recent = true;
+			    			} else if ($flag == 'ANSWERED') {
+				    			$result[$id]->answered = true;
+					    	} else if ($flag == '$FORWARDED') {
+						    	$result[$id]->forwarded = true;
+    						} else if ($flag == 'DRAFT') {
+	    						$result[$id]->is_draft = true;
+		    				} else if ($flag == '$MDNSENT') {
+			    				$result[$id]->mdn_sent = true;
+				    		} else if ($flag == 'FLAGGED') {
+					    	         $result[$id]->flagged = true;
+						    }
+    					}
+	    				$result[$id]->flags = $flags_a;
+		    		}
+			    }
+    		}
+	    } while (!$this->startsWith($line, $key, true));
+
+    	return $result;
+    }
+
+    function fetchHeader($mailbox, $id, $uidfetch=false, $bodystr=false, $add='')
+    {
+	    $a  = $this->fetchHeaders($mailbox, $id, $uidfetch, $bodystr, $add);
+	    if (is_array($a)) {
+		    return array_shift($a);
+	    }
+	    return false;
+    }
+
+    function sortHeaders($a, $field, $flag)
+    {
+	    if (empty($field)) {
+	        $field = 'uid';
+	    }
+        else {
+    	    $field = strtolower($field);
+        }
+
+	    if ($field == 'date' || $field == 'internaldate') {
+	        $field = 'timestamp';
+	    }
+    	if (empty($flag)) {
+	        $flag = 'ASC';
+	    } else {
+        	$flag = strtoupper($flag);
+        }
+
+	    $stripArr = ($field=='subject') ? array('Re: ','Fwd: ','Fw: ','"') : array('"');
+
+	    $c = count($a);
+	    if ($c > 0) {
+		    
+			// Strategy:
+			// First, we'll create an "index" array.
+			// Then, we'll use sort() on that array, 
+			// and use that to sort the main array.
+                
+		    // create "index" array
+		    $index = array();
+		    reset($a);
+		    while (list($key, $val) = each($a)) {
+			    if ($field == 'timestamp') {
+				    $data = $this->strToTime($val->date);
+				    if (!$data) {
+					    $data = $val->timestamp;
+            		}
+			    } else {
+				    $data = $val->$field;
+				    if (is_string($data)) {
+					    $data = strtoupper(str_replace($stripArr, '', $data));
+            		}
+			    }
+    			$index[$key]=$data;
+	    	}
+		
+		    // sort index
+    		$i = 0;
+	    	if ($flag == 'ASC') {
+		    	asort($index);
+    		} else {
+        	    arsort($index);
+		    }
+
+    		// form new array based on index 
+	    	$result = array();
+		    reset($index);
+    		while (list($key, $val) = each($index)) {
+	    		$result[$key]=$a[$key];
+		    	$i++;
+		    }
+	    }
+	
+	    return $result;
+    }
+
+    function expunge($mailbox, $messages=NULL)
+    {
+	    if (!$this->select($mailbox)) {
+            return -1;
+        }
+		
+        $c = 0;
+		$command = $messages ? "UID EXPUNGE $messages" : "EXPUNGE";
+
+		if (!$this->putLine("exp1 $command")) {
+            return -1;
+        }
+
+		do {
+			$line = $this->readLine(100);
+			if ($line[0] == '*') {
+            	$c++;
+        	}
+		} while (!$this->startsWith($line, 'exp1', true, true));
+		
+		if ($this->parseResult($line) == 0) {
+			$this->selected = ''; // state has changed, need to reselect
+			return $c;
+		}
+		$this->error = $line;
+	    return -1;
+    }
+
+    function modFlag($mailbox, $messages, $flag, $mod)
+    {
+	    if ($mod != '+' && $mod != '-') {
+	        return -1;
+	    }
+    
+	    $flag = $this->flags[strtoupper($flag)];
+    
+	    if (!$this->select($mailbox)) {
+	        return -1;
+	    }
+    
+        $c = 0;
+	    if (!$this->putLine("flg UID STORE $messages {$mod}FLAGS ($flag)")) {
+            return false;
+        }
+
+	    do {
+		    $line = $this->readLine(1000);
+		    if ($line[0] == '*') {
+		        $c++;
+            }
+	    } while (!$this->startsWith($line, 'flg', true, true));
+
+	    if ($this->parseResult($line) == 0) {
+		    return $c;
+	    }
+
+	    $this->error = $line;
+	    return -1;
+    }
+
+    function flag($mailbox, $messages, $flag) {
+	    return $this->modFlag($mailbox, $messages, $flag, '+');
+    }
+
+    function unflag($mailbox, $messages, $flag) {
+	    return $this->modFlag($mailbox, $messages, $flag, '-');
+    }
+
+    function delete($mailbox, $messages) {
+	    return $this->modFlag($mailbox, $messages, 'DELETED', '+');
+    }
+
+    function copy($messages, $from, $to)
+    {
+	    if (empty($from) || empty($to)) {
+	        return -1;
+	    }
+    
+	    if (!$this->select($from)) {
+            return -1;
+	    }
+	
+        $this->putLine("cpy1 UID COPY $messages \"".$this->escape($to)."\"");
+	    $line = $this->readReply();
+	    return $this->parseResult($line);
+    }
+
+    function countUnseen($folder)
+    {
+        $index = $this->search($folder, 'ALL UNSEEN');
+        if (is_array($index))
+            return count($index);
+        return false;
+    }
+
+    // Don't be tempted to change $str to pass by reference to speed this up - it will slow it down by about
+    // 7 times instead :-) See comments on http://uk2.php.net/references and this article:
+    // http://derickrethans.nl/files/phparch-php-variables-article.pdf
+    private function parseThread($str, $begin, $end, $root, $parent, $depth, &$depthmap, &$haschildren)
+    {
+	    $node = array();
+	    if ($str[$begin] != '(') {
+		    $stop = $begin + strspn($str, "1234567890", $begin, $end - $begin);
+		    $msg = substr($str, $begin, $stop - $begin);
+		    if ($msg == 0)
+		        return $node;
+		    if (is_null($root))
+			    $root = $msg;
+		    $depthmap[$msg] = $depth;
+		    $haschildren[$msg] = false;
+		    if (!is_null($parent))
+			    $haschildren[$parent] = true;
+		    if ($stop + 1 < $end)
+			    $node[$msg] = $this->parseThread($str, $stop + 1, $end, $root, $msg, $depth + 1, $depthmap, $haschildren);
+		    else
+			    $node[$msg] = array();
+	    } else {
+		    $off = $begin;
+		    while ($off < $end) {
+			    $start = $off;
+    			$off++;
+	    		$n = 1;
+		    	while ($n > 0) {
+			    	$p = strpos($str, ')', $off);
+				    if ($p === false) {
+					    error_log('Mismatched brackets parsing IMAP THREAD response:');
+    					error_log(substr($str, ($begin < 10) ? 0 : ($begin - 10), $end - $begin + 20));
+	    				error_log(str_repeat(' ', $off - (($begin < 10) ? 0 : ($begin - 10))));
+		    			return $node;
+			    	}
+				    $p1 = strpos($str, '(', $off);
+    				if ($p1 !== false && $p1 < $p) {
+	    				$off = $p1 + 1;
+		    			$n++;
+			    	} else {
+				    	$off = $p + 1;
+					    $n--;
+    				}
+	    		}
+		    	$node += $this->parseThread($str, $start + 1, $off - 1, $root, $parent, $depth, $depthmap, $haschildren);
+		    }
+	    }
+	
+	    return $node;
+    }
+
+    function thread($folder, $algorithm='REFERENCES', $criteria='', $encoding='US-ASCII')
+    {
+	    if (!$this->select($folder)) {
+		    return false;
+	    }
+
+    	$encoding  = $encoding ? trim($encoding) : 'US-ASCII';
+	    $algorithm = $algorithm ? trim($algorithm) : 'REFERENCES';
+	    $criteria  = $criteria ? 'ALL '.trim($criteria) : 'ALL';
+		
+	    if (!$this->putLineC("thrd1 THREAD $algorithm $encoding $criteria")) {
+		    return false;
+	    }
+	    do {
+		    $line = trim($this->readLine(10000));
+		    if (preg_match('/^\* THREAD/', $line)) {
+			    $str         = trim(substr($line, 8));
+	    		$depthmap    = array();
+		    	$haschildren = array();
+			    $tree = $this->parseThread($str, 0, strlen($str), null, null, 0, $depthmap, $haschildren);
+		    }
+	    } while (!$this->startsWith($line, 'thrd1', true, true));
+
+    	$result_code = $this->parseResult($line);
+	    if ($result_code == 0) {
+    	    return array($tree, $depthmap, $haschildren);
+	    }
+
+    	$this->error = "Thread: $line";
+	    return false;	
+    }
+
+    function search($folder, $criteria)
+    {
+	    if (!$this->select($folder)) {
+    		return false;
+	    }
+
+    	$data = '';
+	    $query = "srch1 SEARCH " . chop($criteria);
+
+	    if (!$this->putLineC($query)) {
+		    return false;
+	    }
+    	do {
+	    	$line = trim($this->readLine());
+		    if ($this->startsWith($line, '* SEARCH')) {
+    			$data .= substr($line, 8);
+	    	} else if (preg_match('/^[0-9 ]+$/', $line)) {
+		    	$data .= $line;
+		    }
+    	} while (!$this->startsWith($line, 'srch1', true, true));
+
+	    $result_code = $this->parseResult($line);
+	    if ($result_code == 0) {
+		    return preg_split('/\s+/', $data, -1, PREG_SPLIT_NO_EMPTY);
+	    }
+
+    	$this->error = "Search: $line";
+	    return false;	
+    }
+
+    function move($messages, $from, $to)
+    {
+        if (!$from || !$to) {
+            return -1;
+        }
+    
+        $r = $this->copy($messages, $from, $to);
+
+        if ($r==0) {
+            return $this->delete($from, $messages);
+        }
+        return $r;
+    }
+
+    function listMailboxes($ref, $mailbox)
+    {
+		if (empty($mailbox)) {
+	        $mailbox = '*';
+	    }
+	
+	    if (empty($ref) && $this->rootdir) {
+	        $ref = $this->rootdir;
+	    }
+    
+    	// send command
+	    if (!$this->putLine("lmb LIST \"". $this->escape($ref) ."\" \"". $this->escape($mailbox) ."\"")) {
+	        return false;
+	    }
+    
+	    $i = 0;
+	    // get folder list
+	    do {
+		    $line = $this->readLine(500);
+		    $line = $this->multLine($line, true);
+
+		    $a = explode(' ', $line);
+		    if (($line[0] == '*') && ($a[1] == 'LIST')) {
+			    $line = rtrim($line);
+        		// split one line
+			    $a = rcube_explode_quoted_string(' ', $line);
+        		// last string is folder name
+			    $folders[$i] = preg_replace(array('/^"/', '/"$/'), '', $this->unEscape($a[count($a)-1]));
+		        // second from last is delimiter
+        		$delim = trim($a[count($a)-2], '"');
+        		// is it a container?
+        		$i++;
+		    }
+	    } while (!$this->startsWith($line, 'lmb', true));
+
+	    if (is_array($folders)) {
+    	    if (!empty($ref)) {
+            	// if rootdir was specified, make sure it's the first element
+        	    // some IMAP servers (i.e. Courier) won't return it
+            	if ($ref[strlen($ref)-1]==$delim)
+	    	        $ref = substr($ref, 0, strlen($ref)-1);
+    	    	if ($folders[0]!=$ref)
+		            array_unshift($folders, $ref);
+    	    }
+    	    return $folders;
+	    } else if ($this->parseResult($line) == 0) {
+		    return array('INBOX');
+        }
+
+	    $this->error = $line;
+    	return false;
+    }
+
+    function listSubscribed($ref, $mailbox)
+    {
+	    if (empty($mailbox)) {
+		    $mailbox = '*';
+	    }
+	    if (empty($ref) && $this->rootdir) {
+		    $ref = $this->rootdir;
+	    }
+
+	    $folders = array();
+
+    	// send command
+	    if (!$this->putLine('lsb LSUB "'. $this->escape($ref) . '" "' . $this->escape($mailbox).'"')) {
+		    $this->error = "Couldn't send LSUB command";
+		    return false;
+	    }
+	
+    	$i = 0;
+	
+	    // get folder list
+	    do {
+		    $line = $this->readLine(500);
+    		$line = $this->multLine($line, true);
+	    	$a    = explode(' ', $line);
+        
+		    if (($line[0] == '*') && ($a[1] == 'LSUB' || $a[1] == 'LIST')) {
+			    $line = rtrim($line);
+            
+        		// split one line
+			    $a = rcube_explode_quoted_string(' ', $line);
+        		// last string is folder name
+    			$folder = preg_replace(array('/^"/', '/"$/'), '', $this->UnEscape($a[count($a)-1]));
+	    		// @TODO: do we need this check???
+		    	if (!in_array($folder, $folders)) {
+			        $folders[$i] = $folder;
+        		}
+        		// second from last is delimiter
+        		$delim = trim($a[count($a)-2], '"');
+        		// is it a container?
+        		$i++;
+		    }
+	    } while (!$this->startsWith($line, 'lsb', true));
+
+	    if (is_array($folders)) {
+    	    if (!empty($ref)) {
+            	// if rootdir was specified, make sure it's the first element
+        	    // some IMAP servers (i.e. Courier) won't return it
+            	if ($ref[strlen($ref)-1]==$delim) {
+            	    $ref = substr($ref, 0, strlen($ref)-1);
+            	}
+            	if ($folders[0]!=$ref) {
+            	    array_unshift($folders, $ref);
+        	    }
+    	    }
+    	    return $folders;
+	    }
+	    $this->error = $line;
+    	return false;
+    }
+
+    function fetchMIMEHeaders($mailbox, $id, $parts, $mime=true)
+    {
+	    if (!$this->select($mailbox)) {
+		    return false;
+	    }
+	
+    	$result = false;
+	    $parts  = (array) $parts;
+    	$key    = 'fmh0';
+	    $peeks  = '';
+    	$idx    = 0;
+        $type   = $mime ? 'MIME' : 'HEADER';
+
+	    // format request
+	    foreach($parts as $part)
+		    $peeks[] = "BODY.PEEK[$part.$type]";
+	
+	    $request = "$key FETCH $id (" . implode(' ', $peeks) . ')';
+
+	    // send request
+	    if (!$this->putLine($request)) {
+	        return false;
+	    }
+        
+	    do {
+        	$line = $this->readLine(1000);
+        	$line = $this->multLine($line);
+
+		    if (preg_match('/BODY\[([0-9\.]+)\.'.$type.'\]/', $line, $matches)) {
+			    $idx = $matches[1];
+    			$result[$idx] = preg_replace('/^(\* '.$id.' FETCH \()?\s*BODY\['.$idx.'\.'.$type.'\]\s+/', '', $line);
+	    		$result[$idx] = trim($result[$idx], '"');
+	        	$result[$idx] = rtrim($result[$idx], "\t\r\n\0\x0B");
+    		}
+	    } while (!$this->startsWith($line, $key, true));
+
+	    return $result;
+    }
+
+    function fetchPartHeader($mailbox, $id, $is_uid=false, $part=NULL)
+    {
+	    $part = empty($part) ? 'HEADER' : $part.'.MIME';
+
+        return $this->handlePartBody($mailbox, $id, $is_uid, $part);
+    }
+
+    function handlePartBody($mailbox, $id, $is_uid=false, $part='', $encoding=NULL, $print=NULL, $file=NULL)
+    {
+    	if (!$this->select($mailbox)) {
+            return false;
+        }
+
+	    switch ($encoding) {
+		    case 'base64':
+			    $mode = 1;
+    		break;
+	    	case 'quoted-printable':
+		    	$mode = 2;
+    		break;
+	    	case 'x-uuencode':
+		    case 'x-uue':
+    		case 'uue':
+	    	case 'uuencode':
+		    	$mode = 3;
+    		break;
+	    	default:
+		    	$mode = 0;
+	    }
+	
+   		$reply_key = '* ' . $id;
+    	$result = false;
+
+    	// format request
+		$key     = 'ftch0';
+		$request = $key . ($is_uid ? ' UID' : '') . " FETCH $id (BODY.PEEK[$part])";
+    	// send request
+		if (!$this->putLine($request)) {
+		    return false;
+   		}
+
+   		// receive reply line
+   		do {
+       		$line = chop($this->readLine(1000));
+       		$a    = explode(' ', $line);
+   		} while (!($end = $this->startsWith($line, $key, true)) && $a[2] != 'FETCH');
+
+   		$len = strlen($line);
+
+		// handle empty "* X FETCH ()" response
+    	if ($line[$len-1] == ')' && $line[$len-2] != '(') {
+        	// one line response, get everything between first and last quotes
+			if (substr($line, -4, 3) == 'NIL') {
+				// NIL response
+				$result = '';
+			} else {
+			    $from = strpos($line, '"') + 1;
+        		$to   = strrpos($line, '"');
+		        $len  = $to - $from;
+				$result = substr($line, $from, $len);
+			}
+
+        	if ($mode == 1)
+				$result = base64_decode($result);
+			else if ($mode == 2)
+				$result = quoted_printable_decode($result);
+			else if ($mode == 3)
+				$result = convert_uudecode($result);
+
+    	} else if ($line[$len-1] == '}') {
+	        // multi-line request, find sizes of content and receive that many bytes
+        	$from     = strpos($line, '{') + 1;
+	        $to       = strrpos($line, '}');
+        	$len      = $to - $from;
+	        $sizeStr  = substr($line, $from, $len);
+        	$bytes    = (int)$sizeStr;
+			$prev	  = '';
+			
+        	while ($bytes > 0) {
+    		    $line = $this->readLine(1024);
+            	$len  = strlen($line);
+                
+		        if ($len > $bytes) {
+            		$line = substr($line, 0, $bytes);
+					$len = strlen($line);
+		        }
+            	$bytes -= $len;
+
+		        if ($mode == 1) {
+					$line = rtrim($line, "\t\r\n\0\x0B");
+					// create chunks with proper length for base64 decoding
+					$line = $prev.$line;
+					$length = strlen($line);
+					if ($length % 4) {
+						$length = floor($length / 4) * 4;
+						$prev = substr($line, $length);
+						$line = substr($line, 0, $length);
+					}
+					else
+						$prev = '';
+						
+					if ($file)
+						fwrite($file, base64_decode($line));
+            		else if ($print)
+						echo base64_decode($line);
+					else
+						$result .= base64_decode($line);
+				} else if ($mode == 2) {
+					$line = rtrim($line, "\t\r\0\x0B");
+					if ($file)
+						fwrite($file, quoted_printable_decode($line));
+            		else if ($print)
+						echo quoted_printable_decode($line);
+					else
+						$result .= quoted_printable_decode($line);
+				} else if ($mode == 3) {
+					$line = rtrim($line, "\t\r\n\0\x0B");
+					if ($line == 'end' || preg_match('/^begin\s+[0-7]+\s+.+$/', $line))
+						continue;
+					if ($file)
+						fwrite($file, convert_uudecode($line));
+            		else if ($print)
+						echo convert_uudecode($line);
+					else
+						$result .= convert_uudecode($line);
+				} else {
+					$line = rtrim($line, "\t\r\n\0\x0B");
+					if ($file)
+						fwrite($file, $line . "\n");
+            		else if ($print)
+						echo $line . "\n";
+					else
+						$result .= $line . "\n";
+				}
+        	}
+    	}
+	    
+        // read in anything up until last line
+		if (!$end)
+			do {
+        			$line = $this->readLine(1024);
+			} while (!$this->startsWith($line, $key, true));
+
+   		if ($result) {
+	    	if ($file) {
+		    	fwrite($file, $result);
+   			} else if ($print) {
+    			echo $result;
+	    	} else
+		    	return $result;
+   			return true;
+   		}
+
+	    return false;
+    }
+
+    function createFolder($folder)
+    {
+	    if ($this->putLine('c CREATE "' . $this->escape($folder) . '"')) {
+		    do {
+			    $line = $this->readLine(300);
+		    } while (!$this->startsWith($line, 'c ', true, true));
+		    return ($this->parseResult($line) == 0);
+	    }
+	    return false;
+    }
+
+    function renameFolder($from, $to)
+    {
+	    if ($this->putLine('r RENAME "' . $this->escape($from) . '" "' . $this->escape($to) . '"')) {
+		    do {
+			    $line = $this->readLine(300);
+		    } while (!$this->startsWith($line, 'r ', true, true));
+		    return ($this->parseResult($line) == 0);
+	    }
+	    return false;
+    }
+
+    function deleteFolder($folder)
+    {
+	    if ($this->putLine('d DELETE "' . $this->escape($folder). '"')) {
+		    do {
+			    $line = $this->readLine(300);
+		    } while (!$this->startsWith($line, 'd ', true, true));
+		    return ($this->parseResult($line) == 0);
+	    }
+	    return false;
+    }
+
+    function clearFolder($folder)
+    {
+	    $num_in_trash = $this->countMessages($folder);
+	    if ($num_in_trash > 0) {
+		    $this->delete($folder, '1:*');
+	    }
+	    return ($this->expunge($folder) >= 0);
+    }
+
+    function subscribe($folder)
+    {
+	    $query = 'sub1 SUBSCRIBE "' . $this->escape($folder). '"';
+	    $this->putLine($query);
+
+    	$line = trim($this->readLine(512));
+	    return ($this->parseResult($line) == 0);
+    }
+
+    function unsubscribe($folder)
+    {
+        $query = 'usub1 UNSUBSCRIBE "' . $this->escape($folder) . '"';
+	    $this->putLine($query);
+    
+	    $line = trim($this->readLine(512));
+	    return ($this->parseResult($line) == 0);
+    }
+
+    function append($folder, &$message)
+    {
+	    if (!$folder) {
+		    return false;
+	    }
+
+    	$message = str_replace("\r", '', $message);
+	    $message = str_replace("\n", "\r\n", $message);
+
+    	$len = strlen($message);
+	    if (!$len) {
+		    return false;
+	    }
+
+	    $request = 'a APPEND "' . $this->escape($folder) .'" (\\Seen) {' . $len . '}';
+
+	    if ($this->putLine($request)) {
+		    $line = $this->readLine(512);
+
+    		if ($line[0] != '+') {
+	    		// $errornum = $this->parseResult($line);
+		    	$this->error = "Cannot write to folder: $line";
+			    return false;
+    		}
+
+	    	if (!$this->putLine($message)) {
+                return false;
+            }
+
+		    do {
+			    $line = $this->readLine();
+    		} while (!$this->startsWith($line, 'a ', true, true));
+	
+	    	$result = ($this->parseResult($line) == 0);
+		    if (!$result) {
+		        $this->error = $line;
+		    }
+    		return $result;
+	    }
+
+	    $this->error = "Couldn't send command \"$request\"";
+	    return false;
+    }
+
+    function appendFromFile($folder, $path, $headers=null, $separator="\n\n")
+    {
+	    if (!$folder) {
+	        return false;
+	    }
+    
+	    // open message file
+	    $in_fp = false;
+	    if (file_exists(realpath($path))) {
+		    $in_fp = fopen($path, 'r');
+	    }
+	    if (!$in_fp) { 
+		    $this->error = "Couldn't open $path for reading";
+		    return false;
+	    }
+	
+	    $len = filesize($path);
+	    if (!$len) {
+		    return false;
+	    }
+
+        if ($headers) {
+            $headers = preg_replace('/[\r\n]+$/', '', $headers);
+            $len += strlen($headers) + strlen($separator);
+        }
+
+    	// send APPEND command
+	    $request    = 'a APPEND "' . $this->escape($folder) . '" (\\Seen) {' . $len . '}';
+	    if ($this->putLine($request)) {
+		    $line = $this->readLine(512);
+
+		    if ($line[0] != '+') {
+			    //$errornum = $this->parseResult($line);
+			    $this->error = "Cannot write to folder: $line";
+			    return false;
+		    }
+
+            // send headers with body separator
+            if ($headers) {
+			    $this->putLine($headers . $separator, false);
+            }
+
+		    // send file
+		    while (!feof($in_fp) && $this->fp) {
+			    $buffer = fgets($in_fp, 4096);
+			    $this->putLine($buffer, false);
+		    }
+		    fclose($in_fp);
+
+		    if (!$this->putLine('')) { // \r\n
+                return false;
+            }
+
+		    // read response
+		    do {
+			    $line = $this->readLine();
+		    } while (!$this->startsWith($line, 'a ', true, true));
+
+		    $result = ($this->parseResult($line) == 0);
+		    if (!$result) {
+		        $this->error = $line;
+		    }
+
+		    return $result;
+	    }
+	
+    	$this->error = "Couldn't send command \"$request\"";
+	    return false;
+    }
+
+    function fetchStructureString($folder, $id, $is_uid=false)
+    {
+	    if (!$this->select($folder)) {
+            return false;
+        }
+
+		$key = 'F1247';
+    	$result = false;
+
+		if ($this->putLine($key . ($is_uid ? ' UID' : '') ." FETCH $id (BODYSTRUCTURE)")) {
+			do {
+				$line = $this->readLine(5000);
+				$line = $this->multLine($line, true);
+				if (!preg_match("/^$key/", $line))
+					$result .= $line;
+			} while (!$this->startsWith($line, $key, true, true));
+
+			$result = trim(substr($result, strpos($result, 'BODYSTRUCTURE')+13, -1));
+		}
+
+    	return $result;
+    }
+
+    function getQuota()
+    {
+        /*
+         * GETQUOTAROOT "INBOX"
+         * QUOTAROOT INBOX user/rchijiiwa1
+         * QUOTA user/rchijiiwa1 (STORAGE 654 9765)
+         * OK Completed
+         */
+	    $result      = false;
+	    $quota_lines = array();
+	
+	    // get line(s) containing quota info
+	    if ($this->putLine('QUOT1 GETQUOTAROOT "INBOX"')) {
+		    do {
+			    $line = chop($this->readLine(5000));
+			    if ($this->startsWith($line, '* QUOTA ')) {
+				    $quota_lines[] = $line;
+        		}
+		    } while (!$this->startsWith($line, 'QUOT1', true, true));
+	    }
+	
+	    // return false if not found, parse if found
+	    $min_free = PHP_INT_MAX;
+	    foreach ($quota_lines as $key => $quota_line) {
+		    $quota_line   = preg_replace('/[()]/', '', $quota_line);
+		    $parts        = explode(' ', $quota_line);
+		    $storage_part = array_search('STORAGE', $parts);
+		
+		    if (!$storage_part)
+                continue;
+	
+		    $used  = intval($parts[$storage_part+1]);
+		    $total = intval($parts[$storage_part+2]);
+		    $free  = $total - $used; 
+	
+		    // return lowest available space from all quotas
+		    if ($free < $min_free) { 
+		        $min_free          = $free; 
+			    $result['used']    = $used;
+			    $result['total']   = $total;
+			    $result['percent'] = min(100, round(($used/max(1,$total))*100));
+			    $result['free']    = 100 - $result['percent'];
+		    }
+	    }
+
+	    return $result;
+    }
+
+    private function iil_xor($string, $string2)
+    {
+	    $result = '';
+	    $size = strlen($string);
+	    for ($i=0; $i<$size; $i++) {
+    		$result .= chr(ord($string[$i]) ^ ord($string2[$i]));
+	    }
+	    return $result;
+    }
+
+    private function strToTime($date)
+    {
+	    // support non-standard "GMTXXXX" literal
+	    $date = preg_replace('/GMT\s*([+-][0-9]+)/', '\\1', $date);
+        // if date parsing fails, we have a date in non-rfc format.
+	    // remove token from the end and try again
+	    while ((($ts = @strtotime($date))===false) || ($ts < 0)) {
+	        $d = explode(' ', $date);
+		    array_pop($d);
+		    if (!$d) break;
+		    $date = implode(' ', $d);
+	    }
+
+	    $ts = (int) $ts;
+
+	    return $ts < 0 ? 0 : $ts;	
+    }
+
+    private function SplitHeaderLine($string)
+    {
+	    $pos = strpos($string, ':');
+	    if ($pos>0) {
+		    $res[0] = substr($string, 0, $pos);
+		    $res[1] = trim(substr($string, $pos+1));
+		    return $res;
+	    }
+    	return $string;
+    }
+
+    private function parseNamespace($str, &$i, $len=0, $l)
+    {
+	    if (!$l) {
+	        $str = str_replace('NIL', '()', $str);
+	    }
+	    if (!$len) {
+	        $len = strlen($str);
+	    }
+	    $data      = array();
+	    $in_quotes = false;
+	    $elem      = 0;
+	
+        for ($i;$i<$len;$i++) {
+		    $c = (string)$str[$i];
+		    if ($c == '(' && !$in_quotes) {
+			    $i++;
+			    $data[$elem] = $this->parseNamespace($str, $i, $len, $l++);
+			    $elem++;
+		    } else if ($c == ')' && !$in_quotes) {
+			    return $data;
+    		} else if ($c == '\\') {
+			    $i++;
+			    if ($in_quotes) {
+				    $data[$elem] .= $c.$str[$i];
+        		}
+		    } else if ($c == '"') {
+			    $in_quotes = !$in_quotes;
+			    if (!$in_quotes) {
+				    $elem++;
+        		}
+		    } else if ($in_quotes) {
+			    $data[$elem].=$c;
+		    }
+	    }
+	    
+        return $data;
+    }
+
+    private function escape($string)
+    {
+	    return strtr($string, array('"'=>'\\"', '\\' => '\\\\')); 
+    }
+
+    private function unEscape($string)
+    {
+	    return strtr($string, array('\\"'=>'"', '\\\\' => '\\')); 
+    }
+
+}
+
+?>