githubFork/roundcubemail.git

			@@ -5,12 +5,15 @@
			\| program/include/rcube_imap.php \|
			\| \|
			\| This file is part of the Roundcube Webmail client \|
			\| Copyright (C) 2005-2011, The Roundcube Dev Team \|
			\| Copyright (C) 2011, Kolab Systems AG \|
			\| Licensed under the GNU GPL \|
			\| Copyright (C) 2005-2012, The Roundcube Dev Team \|
			\| Copyright (C) 2011-2012, Kolab Systems AG \|
			\| \|
			\| Licensed under the GNU General Public License version 3 or \|
			\| any later version with exceptions for skins & plugins. \|
			\| See the README file for a full license statement. \|
			\| \|
			\| PURPOSE: \|
			\| IMAP Engine \|
			\| IMAP Storage Engine \|
			\| \|
			+-----------------------------------------------------------------------+
			\| Author: Thomas Bruederli <roundcube@gmail.com> \|
			@@ -30,15 +33,8 @@
			* @author Aleksander Machniak <alec@alec.pl>
			* @version 2.0
			*/
			class rcube_imap
			class rcube_imap extends rcube_storage
			{
			public $skip_deleted = false;
			public $page_size = 10;
			public $list_page = 1;
			public $threading = false;
			public $fetch_add_headers = '';
			public $get_all_headers = false;

			/**
			* Instance of rcube_imap_generic
			*
			@@ -51,87 +47,70 @@
			*
			* @var rcube_imap_cache
			*/
			private $mcache;
			protected $mcache;

			/**
			* Instance of rcube_cache
			*
			* @var rcube_cache
			*/
			private $cache;
			protected $cache;

			/**
			* Internal (in-memory) cache
			*
			* @var array
			*/
			private $icache = array();
			protected $icache = array();

			private $mailbox = 'INBOX';
			private $delimiter = NULL;
			private $namespace = NULL;
			private $sort_field = '';
			private $sort_order = 'DESC';
			private $default_charset = 'ISO-8859-1';
			private $struct_charset = NULL;
			private $default_folders = array('INBOX');
			private $uid_id_map = array();
			private $msg_headers = array();
			public $search_set = NULL;
			public $search_string = '';
			private $search_charset = '';
			private $search_sort_field = '';
			private $search_threads = false;
			private $search_sorted = false;
			private $options = array('auth_method' => 'check');
			private $host, $user, $pass, $port, $ssl;
			private $caching = false;
			private $messages_caching = false;

			/**
			* All (additional) headers used (in any way) by Roundcube
			* Not listed here: DATE, FROM, TO, CC, REPLY-TO, SUBJECT, CONTENT-TYPE, LIST-POST
			* (used for messages listing) are hardcoded in rcube_imap_generic::fetchHeaders()
			*
			* @var array
			* @see rcube_imap::fetch_add_headers
			*/
			private $all_headers = array(
			'IN-REPLY-TO',
			'BCC',
			'MESSAGE-ID',
			'CONTENT-TRANSFER-ENCODING',
			'REFERENCES',
			'X-DRAFT-INFO',
			'MAIL-FOLLOWUP-TO',
			'MAIL-REPLY-TO',
			'RETURN-PATH',
			);

			const UNKNOWN = 0;
			const NOPERM = 1;
			const READONLY = 2;
			const TRYCREATE = 3;
			const INUSE = 4;
			const OVERQUOTA = 5;
			const ALREADYEXISTS = 6;
			const NONEXISTENT = 7;
			const CONTACTADMIN = 8;
			protected $list_page = 1;
			protected $delimiter;
			protected $namespace;
			protected $sort_field = '';
			protected $sort_order = 'DESC';
			protected $struct_charset;
			protected $uid_id_map = array();
			protected $msg_headers = array();
			protected $search_set;
			protected $search_string = '';
			protected $search_charset = '';
			protected $search_sort_field = '';
			protected $search_threads = false;
			protected $search_sorted = false;
			protected $options = array('auth_method' => 'check');
			protected $caching = false;
			protected $messages_caching = false;
			protected $threading = false;


			/**
			* Object constructor.
			*/
			function __construct()
			public function __construct()
			{
			$this->conn = new rcube_imap_generic();

			// Set namespace and delimiter from session,
			// so some methods would work before connection
			if (isset($_SESSION['imap_namespace']))
			if (isset($_SESSION['imap_namespace'])) {
			$this->namespace = $_SESSION['imap_namespace'];
			if (isset($_SESSION['imap_delimiter']))
			}
			if (isset($_SESSION['imap_delimiter'])) {
			$this->delimiter = $_SESSION['imap_delimiter'];
			}
			}


			/**
			* Magic getter for backward compat.
			*
			* @deprecated.
			*/
			public function __get($name)
			{
			if (isset($this->{$name})) {
			return $this->{$name};
			}
			}


			@@ -143,16 +122,17 @@
			* @param string $pass Password for IMAP account
			* @param integer $port Port to connect to
			* @param string $use_ssl SSL schema (either ssl or tls) or null if plain connection
			*
			* @return boolean TRUE on success, FALSE on failure
			* @access public
			*/
			function connect($host, $user, $pass, $port=143, $use_ssl=null)
			public function connect($host, $user, $pass, $port=143, $use_ssl=null)
			{
			// check for OpenSSL support in PHP build
			if ($use_ssl && extension_loaded('openssl'))
			if ($use_ssl && extension_loaded('openssl')) {
			$this->options['ssl_mode'] = $use_ssl == 'imaps' ? 'ssl' : $use_ssl;
			}
			else if ($use_ssl) {
			raise_error(array('code' => 403, 'type' => 'imap',
			rcube::raise_error(array('code' => 403, 'type' => 'imap',
			'file' => __FILE__, 'line' => __LINE__,
			'message' => "OpenSSL not available"), true, false);
			$port = 143;
			@@ -161,7 +141,7 @@
			$this->options['port'] = $port;

			if ($this->options['debug']) {
			$this->conn->setDebug(true, array($this, 'debug_handler'));
			$this->set_debug(true);

			$this->options['ident'] = array(
			'name' => 'Roundcube Webmail',
			@@ -174,21 +154,27 @@

			$attempt = 0;
			do {
			$data = rcmail::get_instance()->plugins->exec_hook('imap_connect',
			$data = rcube::get_instance()->plugins->exec_hook('imap_connect',
			array_merge($this->options, array('host' => $host, 'user' => $user,
			'attempt' => ++$attempt)));

			if (!empty($data['pass']))
			if (!empty($data['pass'])) {
			$pass = $data['pass'];
			}

			$this->conn->connect($data['host'], $data['user'], $pass, $data);
			} while(!$this->conn->connected() && $data['retry']);

			$this->host = $data['host'];
			$this->user = $data['user'];
			$this->pass = $pass;
			$this->port = $port;
			$this->ssl = $use_ssl;
			$config = array(
			'host' => $data['host'],
			'user' => $data['user'],
			'password' => $pass,
			'port' => $port,
			'ssl' => $use_ssl,
			);

			$this->options = array_merge($this->options, $config);
			$this->connect_done = true;

			if ($this->conn->connected()) {
			// get namespace and delimiter
			@@ -199,9 +185,9 @@
			else if ($this->conn->error) {
			if ($pass && $user) {
			$message = sprintf("Login failed for %s from %s. %s",
			$user, rcmail_remote_ip(), $this->conn->error);
			$user, rcube_utils::remote_ip(), $this->conn->error);

			raise_error(array('code' => 403, 'type' => 'imap',
			rcube::raise_error(array('code' => 403, 'type' => 'imap',
			'file' => __FILE__, 'line' => __LINE__,
			'message' => $message), true, false);
			}
			@@ -212,33 +198,48 @@


			/**
			* Close IMAP connection
			* Close IMAP connection.
			* Usually done on script shutdown
			*
			* @access public
			*/
			function close()
			public function close()
			{
			$this->conn->closeConnection();
			if ($this->mcache)
			if ($this->mcache) {
			$this->mcache->close();
			}
			}


			/**
			* Close IMAP connection and re-connect
			* This is used to avoid some strange socket errors when talking to Courier IMAP
			* Check connection state, connect if not connected.
			*
			* @access public
			* @return bool Connection state.
			*/
			function reconnect()
			public function check_connection()
			{
			$this->conn->closeConnection();
			$connected = $this->connect($this->host, $this->user, $this->pass, $this->port, $this->ssl);
			// Establish connection if it wasn't done yet
			if (!$this->connect_done && !empty($this->options['user'])) {
			return $this->connect(
			$this->options['host'],
			$this->options['user'],
			$this->options['password'],
			$this->options['port'],
			$this->options['ssl']
			);
			}

			// issue SELECT command to restore connection status
			if ($connected && strlen($this->mailbox))
			$this->conn->select($this->mailbox);
			return $this->is_connected();
			}


			/**
			* Checks IMAP connection.
			*
			* @return boolean TRUE on success, FALSE on failure
			*/
			public function is_connected()
			{
			return $this->conn->connected();
			}


			@@ -247,18 +248,18 @@
			*
			* @return int Error code
			*/
			function get_error_code()
			public function get_error_code()
			{
			return $this->conn->errornum;
			}


			/**
			* Returns message of last error
			* Returns text of last error
			*
			* @return string Error message
			* @return string Error string
			*/
			function get_error_str()
			public function get_error_str()
			{
			return $this->conn->error;
			}
			@@ -269,7 +270,7 @@
			*
			* @return int Response code
			*/
			function get_response_code()
			public function get_response_code()
			{
			switch ($this->conn->resultcode) {
			case 'NOPERM':
			@@ -295,34 +296,11 @@


			/**
			* Returns last command response
			*
			* @return string Response
			*/
			function get_response_str()
			{
			return $this->conn->result;
			}


			/**
			* Set options to be used in rcube_imap_generic::connect()
			*
			* @param array $opt Options array
			*/
			function set_options($opt)
			{
			$this->options = array_merge($this->options, (array)$opt);
			}


			/**
			* Activate/deactivate debug mode
			*
			* @param boolean $dbg True if IMAP conversation should be logged
			* @access public
			*/
			function set_debug($dbg = true)
			public function set_debug($dbg = true)
			{
			$this->options['debug'] = $dbg;
			$this->conn->setDebug($dbg, array($this, 'debug_handler'));
			@@ -330,207 +308,110 @@


			/**
			* Set default message charset
			* Set internal folder reference.
			* All operations will be perfomed on this folder.
			*
			* This will be used for message decoding if a charset specification is not available
			*
			* @param string $cs Charset string
			* @access public
			* @param string $folder Folder name
			*/
			function set_charset($cs)
			public function set_folder($folder)
			{
			$this->default_charset = $cs;
			}


			/**
			* This list of folders will be listed above all other folders
			*
			* @param array $arr Indexed list of folder names
			* @access public
			*/
			function set_default_mailboxes($arr)
			{
			if (is_array($arr)) {
			$this->default_folders = $arr;

			// add inbox if not included
			if (!in_array('INBOX', $this->default_folders))
			array_unshift($this->default_folders, 'INBOX');
			}
			}


			/**
			* Set internal mailbox reference.
			*
			* All operations will be perfomed on this mailbox/folder
			*
			* @param string $mailbox Mailbox/Folder name
			* @access public
			*/
			function set_mailbox($mailbox)
			{
			if ($this->mailbox == $mailbox)
			if ($this->folder == $folder) {
			return;

			$this->mailbox = $mailbox;

			// clear messagecount cache for this mailbox
			$this->_clear_messagecount($mailbox);
			}


			/**
			* Forces selection of a mailbox
			*
			* @param string $mailbox Mailbox/Folder name
			* @access public
			*/
			function select_mailbox($mailbox=null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			$selected = $this->conn->select($mailbox);
			$this->folder = $folder;

			if ($selected && $this->mailbox != $mailbox) {
			// clear messagecount cache for this mailbox
			$this->_clear_messagecount($mailbox);
			$this->mailbox = $mailbox;
			}
			// clear messagecount cache for this folder
			$this->clear_messagecount($folder);
			}


			/**
			* Set internal list page
			* Save a search result for future message listing methods
			*
			* @param number $page Page number to list
			* @access public
			* @param array $set Search set, result from rcube_imap::get_search_set():
			* 0 - searching criteria, string
			* 1 - search result, rcube_result_index\|rcube_result_thread
			* 2 - searching character set, string
			* 3 - sorting field, string
			* 4 - true if sorted, bool
			*/
			function set_page($page)
			public function set_search_set($set)
			{
			$this->list_page = (int)$page;
			}
			$set = (array)$set;


			/**
			* Set internal page size
			*
			* @param number $size Number of messages to display on one page
			* @access public
			*/
			function set_pagesize($size)
			{
			$this->page_size = (int)$size;
			}


			/**
			* Save a set of message ids for future message listing methods
			*
			* @param string IMAP Search query
			* @param array List of message ids or NULL if empty
			* @param string Charset of search string
			* @param string Sorting field
			* @param string True if set is sorted (SORT was used for searching)
			*/
			function set_search_set($str=null, $msgs=null, $charset=null, $sort_field=null, $threads=false, $sorted=false)
			{
			if (is_array($str) && $msgs == null)
			list($str, $msgs, $charset, $sort_field, $threads, $sorted) = $str;
			if ($msgs === false)
			$msgs = array();
			else if ($msgs != null && !is_array($msgs))
			$msgs = explode(',', $msgs);

			$this->search_string = $str;
			$this->search_set = $msgs;
			$this->search_charset = $charset;
			$this->search_sort_field = $sort_field;
			$this->search_threads = $threads;
			$this->search_sorted = $sorted;
			$this->search_string = $set[0];
			$this->search_set = $set[1];
			$this->search_charset = $set[2];
			$this->search_sort_field = $set[3];
			$this->search_sorted = $set[4];
			$this->search_threads = is_a($this->search_set, 'rcube_result_thread');
			}


			/**
			* Return the saved search set as hash array
			*
			* @return array Search set
			*/
			function get_search_set()
			public function get_search_set()
			{
			return array($this->search_string,
			if (empty($this->search_set)) {
			return null;
			}

			return array(
			$this->search_string,
			$this->search_set,
			$this->search_charset,
			$this->search_sort_field,
			$this->search_threads,
			$this->search_sorted,
			);
			}


			/**
			* Returns the currently used mailbox name
			*
			* @return string Name of the mailbox/folder
			* @access public
			*/
			function get_mailbox_name()
			{
			return $this->mailbox;
			}


			/**
			* Returns the IMAP server's capability
			* Returns the IMAP server's capability.
			*
			* @param string $cap Capability name
			* @return mixed Capability value or TRUE if supported, FALSE if not
			* @access public
			*/
			function get_capability($cap)
			{
			return $this->conn->getCapability(strtoupper($cap));
			}


			/**
			* Sets threading flag to the best supported THREAD algorithm
			*
			* @param boolean $enable TRUE to enable and FALSE
			* @return string Algorithm or false if THREAD is not supported
			* @access public
			* @return mixed Capability value or TRUE if supported, FALSE if not
			*/
			function set_threading($enable=false)
			public function get_capability($cap)
			{
			$this->threading = false;
			$cap = strtoupper($cap);
			$sess_key = "STORAGE_$cap";

			if ($enable && ($caps = $this->get_capability('THREAD'))) {
			if (in_array('REFS', $caps))
			$this->threading = 'REFS';
			else if (in_array('REFERENCES', $caps))
			$this->threading = 'REFERENCES';
			else if (in_array('ORDEREDSUBJECT', $caps))
			$this->threading = 'ORDEREDSUBJECT';
			if (!isset($_SESSION[$sess_key])) {
			if (!$this->check_connection()) {
			return false;
			}

			$_SESSION[$sess_key] = $this->conn->getCapability($cap);
			}

			return $this->threading;
			return $_SESSION[$sess_key];
			}


			/**
			* Checks the PERMANENTFLAGS capability of the current mailbox
			* Checks the PERMANENTFLAGS capability of the current folder
			* and returns true if the given flag is supported by the IMAP server
			*
			* @param string $flag Permanentflag name
			*
			* @return boolean True if this flag is supported
			* @access public
			*/
			function check_permflag($flag)
			public function check_permflag($flag)
			{
			$flag = strtoupper($flag);
			$imap_flag = $this->conn->flags[$flag];

			if ($this->folder !== null) {
			$this->check_connection();
			}
			// @TODO: cache permanent flags (?)

			return (in_array_nocase($imap_flag, $this->conn->data['PERMANENTFLAGS']));
			}

			@@ -541,7 +422,7 @@
			* @return string Delimiter string
			* @access public
			*/
			function get_hierarchy_delimiter()
			public function get_hierarchy_delimiter()
			{
			return $this->delimiter;
			}
			@@ -553,9 +434,8 @@
			* @param string $name Namespace array index: personal, other, shared, prefix
			*
			* @return array Namespace data
			* @access public
			*/
			function get_namespace($name=null)
			public function get_namespace($name = null)
			{
			$ns = $this->namespace;

			@@ -570,23 +450,22 @@

			/**
			* Sets delimiter and namespaces
			*
			* @access private
			*/
			private function set_env()
			protected function set_env()
			{
			if ($this->delimiter !== null && $this->namespace !== null) {
			return;
			}

			$config = rcmail::get_instance()->config;
			$config = rcube::get_instance()->config;
			$imap_personal = $config->get('imap_ns_personal');
			$imap_other = $config->get('imap_ns_other');
			$imap_shared = $config->get('imap_ns_shared');
			$imap_delimiter = $config->get('imap_delimiter');

			if (!$this->conn->connected())
			if (!$this->check_connection()) {
			return;
			}

			$ns = $this->conn->getNamespace();

			@@ -639,7 +518,7 @@
			}
			}

			// Find personal namespace prefix for mod_mailbox()
			// Find personal namespace prefix for mod_folder()
			// Prefix can be removed when there is only one personal namespace
			if (is_array($this->namespace['personal']) && count($this->namespace['personal']) == 1) {
			$this->namespace['prefix'] = $this->namespace['personal'][0][0];
			@@ -651,77 +530,85 @@


			/**
			* Get message count for a specific mailbox
			* Get message count for a specific folder
			*
			* @param string $mailbox Mailbox/folder name
			* @param string $folder Folder name
			* @param string $mode Mode for count [ALL\|THREADS\|UNSEEN\|RECENT]
			* @param boolean $force Force reading from server and update cache
			* @param boolean $status Enables storing folder status info (max UID/count),
			* required for mailbox_status()
			* required for folder_status()
			*
			* @return int Number of messages
			* @access public
			*/
			function messagecount($mailbox='', $mode='ALL', $force=false, $status=true)
			public function count($folder='', $mode='ALL', $force=false, $status=true)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			return $this->_messagecount($mailbox, $mode, $force, $status);
			return $this->countmessages($folder, $mode, $force, $status);
			}


			/**
			* Private method for getting nr of messages
			* protected method for getting nr of messages
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param string $mode Mode for count [ALL\|THREADS\|UNSEEN\|RECENT]
			* @param boolean $force Force reading from server and update cache
			* @param boolean $status Enables storing folder status info (max UID/count),
			* required for mailbox_status()
			* required for folder_status()
			*
			* @return int Number of messages
			* @access private
			* @see rcube_imap::messagecount()
			* @see rcube_imap::count()
			*/
			private function _messagecount($mailbox, $mode='ALL', $force=false, $status=true)
			protected function countmessages($folder, $mode='ALL', $force=false, $status=true)
			{
			$mode = strtoupper($mode);

			// count search set
			if ($this->search_string && $mailbox == $this->mailbox && ($mode == 'ALL' \|\| $mode == 'THREADS') && !$force) {
			if ($this->search_threads)
			return $mode == 'ALL' ? count((array)$this->search_set['depth']) : count((array)$this->search_set['tree']);
			else
			return count((array)$this->search_set);
			if ($this->search_string && $folder == $this->folder && ($mode == 'ALL' \|\| $mode == 'THREADS') && !$force) {
			if ($mode == 'ALL') {
			return $this->search_set->count_messages();
			}
			else {
			return $this->search_set->count();
			}
			}

			$a_mailbox_cache = $this->get_cache('messagecount');
			$a_folder_cache = $this->get_cache('messagecount');

			// return cached value
			if (!$force && is_array($a_mailbox_cache[$mailbox]) && isset($a_mailbox_cache[$mailbox][$mode]))
			return $a_mailbox_cache[$mailbox][$mode];
			if (!$force && is_array($a_folder_cache[$folder]) && isset($a_folder_cache[$folder][$mode])) {
			return $a_folder_cache[$folder][$mode];
			}

			if (!is_array($a_mailbox_cache[$mailbox]))
			$a_mailbox_cache[$mailbox] = array();
			if (!is_array($a_folder_cache[$folder])) {
			$a_folder_cache[$folder] = array();
			}

			if ($mode == 'THREADS') {
			$res = $this->_threadcount($mailbox, $msg_count);
			$count = $res['count'];
			$res = $this->fetch_threads($folder, $force);
			$count = $res->count();

			if ($status) {
			$this->set_folder_stats($mailbox, 'cnt', $res['msgcount']);
			$this->set_folder_stats($mailbox, 'maxuid', $res['maxuid'] ? $this->id2uid($res['maxuid'], $mailbox) : 0);
			$msg_count = $res->count_messages();
			$this->set_folder_stats($folder, 'cnt', $msg_count);
			$this->set_folder_stats($folder, 'maxuid', $msg_count ? $this->id2uid($msg_count, $folder) : 0);
			}
			}
			// Need connection here
			else if (!$this->check_connection()) {
			return 0;
			}
			// RECENT count is fetched a bit different
			else if ($mode == 'RECENT') {
			$count = $this->conn->countRecent($mailbox);
			$count = $this->conn->countRecent($folder);
			}
			// use SEARCH for message counting
			else if ($this->skip_deleted) {
			else if (!empty($this->options['skip_deleted'])) {
			$search_str = "ALL UNDELETED";
			$keys = array('COUNT');
			$need_uid = false;

			if ($mode == 'UNSEEN') {
			$search_str .= " UNSEEN";
			@@ -732,621 +619,438 @@
			}
			if ($status) {
			$keys[] = 'MAX';
			$need_uid = true;
			}
			}

			// @TODO: if $force==false && $mode == 'ALL' we could try to use cache index here

			// get message count using (E)SEARCH
			// not very performant but more precise (using UNDELETED)
			$index = $this->conn->search($mailbox, $search_str, $need_uid, $keys);

			$count = is_array($index) ? $index['COUNT'] : 0;
			$index = $this->conn->search($folder, $search_str, true, $keys);
			$count = $index->count();

			if ($mode == 'ALL') {
			if ($this->messages_caching) {
			// Save additional info required by cache status check
			$this->icache['undeleted_idx'] = array($mailbox, $index['ALL'], $index['COUNT']);
			}
			// Cache index data, will be used in index_direct()
			$this->icache['undeleted_idx'] = $index;

			if ($status) {
			$this->set_folder_stats($mailbox, 'cnt', $count);
			$this->set_folder_stats($mailbox, 'maxuid', is_array($index) ? $index['MAX'] : 0);
			$this->set_folder_stats($folder, 'cnt', $count);
			$this->set_folder_stats($folder, 'maxuid', $index->max());
			}
			}
			}
			else {
			if ($mode == 'UNSEEN')
			$count = $this->conn->countUnseen($mailbox);
			if ($mode == 'UNSEEN') {
			$count = $this->conn->countUnseen($folder);
			}
			else {
			$count = $this->conn->countMessages($mailbox);
			$count = $this->conn->countMessages($folder);
			if ($status) {
			$this->set_folder_stats($mailbox,'cnt', $count);
			$this->set_folder_stats($mailbox, 'maxuid', $count ? $this->id2uid($count, $mailbox) : 0);
			$this->set_folder_stats($folder,'cnt', $count);
			$this->set_folder_stats($folder, 'maxuid', $count ? $this->id2uid($count, $folder) : 0);
			}
			}
			}

			$a_mailbox_cache[$mailbox][$mode] = (int)$count;
			$a_folder_cache[$folder][$mode] = (int)$count;

			// write back to cache
			$this->update_cache('messagecount', $a_mailbox_cache);
			$this->update_cache('messagecount', $a_folder_cache);

			return (int)$count;
			}


			/**
			* Private method for getting nr of threads
			*
			* @param string $mailbox Folder name
			*
			* @returns array Array containing items: 'count' - threads count,
			* 'msgcount' = messages count, 'maxuid' = max. UID in the set
			* @access private
			*/
			private function _threadcount($mailbox)
			{
			$result = array();

			if (!empty($this->icache['threads'])) {
			$dcount = count($this->icache['threads']['depth']);
			$result = array(
			'count' => count($this->icache['threads']['tree']),
			'msgcount' => $dcount,
			'maxuid' => $dcount ? max(array_keys($this->icache['threads']['depth'])) : 0,
			);
			}
			else if (is_array($result = $this->fetch_threads($mailbox))) {
			$dcount = count($result[1]);
			$result = array(
			'count' => count($result[0]),
			'msgcount' => $dcount,
			'maxuid' => $dcount ? max(array_keys($result[1])) : 0,
			);
			}

			return $result;
			}


			/**
			* Public method for listing headers
			* convert mailbox name with root dir first
			*
			* @param string $mailbox Mailbox/folder name
			* @param string $folder Folder name
			* @param int $page Current page to list
			* @param string $sort_field Header field to sort by
			* @param string $sort_order Sort order [ASC\|DESC]
			* @param int $slice Number of slice items to extract from result array
			*
			* @return array Indexed array with message header objects
			* @access public
			*/
			function list_headers($mailbox='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			public function list_messages($folder='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			return $this->_list_headers($mailbox, $page, $sort_field, $sort_order, $slice);
			return $this->_list_messages($folder, $page, $sort_field, $sort_order, $slice);
			}


			/**
			* Private method for listing message headers
			* protected method for listing message headers
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param int $page Current page to list
			* @param string $sort_field Header field to sort by
			* @param string $sort_order Sort order [ASC\|DESC]
			* @param int $slice Number of slice items to extract from result array
			*
			* @return array Indexed array with message header objects
			* @see rcube_imap::list_headers
			* @see rcube_imap::list_messages
			*/
			private function _list_headers($mailbox='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			protected function _list_messages($folder='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			{
			if (!strlen($mailbox))
			if (!strlen($folder)) {
			return array();
			}

			// use saved message set
			if ($this->search_string && $mailbox == $this->mailbox)
			return $this->_list_header_set($mailbox, $page, $sort_field, $sort_order, $slice);

			if ($this->threading)
			return $this->_list_thread_headers($mailbox, $page, $sort_field, $sort_order, $slice);

			$this->_set_sort_order($sort_field, $sort_order);

			$this->set_sort_order($sort_field, $sort_order);
			$page = $page ? $page : $this->list_page;

			// Use messages cache
			if ($mcache = $this->get_mcache_engine()) {
			$msg_index = $mcache->get_index($mailbox, $this->sort_field, $this->sort_order);

			if (empty($msg_index))
			return array();

			$from = ($page-1) * $this->page_size;
			$to = $from + $this->page_size;
			$msg_index = array_values($msg_index); // UIDs
			$is_uid = true;
			$sorted = true;

			if ($from \|\| $to)
			$msg_index = array_slice($msg_index, $from, $to - $from);

			if ($slice)
			$msg_index = array_slice($msg_index, -$slice, $slice);

			$a_msg_headers = $mcache->get_messages($mailbox, $msg_index);
			}
			// retrieve headers from IMAP
			// use message index sort as default sorting (for better performance)
			else if (!$this->sort_field) {
			if ($this->skip_deleted) {
			// @TODO: this could be cached
			if ($msg_index = $this->_search_index($mailbox, 'ALL UNDELETED')) {
			list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
			$msg_index = array_slice($msg_index, $begin, $end-$begin);
			}
			}
			else if ($max = $this->conn->countMessages($mailbox)) {
			list($begin, $end) = $this->_get_message_range($max, $page);
			$msg_index = range($begin+1, $end);
			}
			else
			$msg_index = array();

			if ($slice && $msg_index)
			$msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);

			// fetch reqested headers from server
			if ($msg_index)
			$a_msg_headers = $this->fetch_headers($mailbox, $msg_index);
			}
			// use SORT command
			else if ($this->get_capability('SORT') &&
			// Courier-IMAP provides SORT capability but allows to disable it by admin (#1486959)
			($msg_index = $this->conn->sort($mailbox, $this->sort_field,
			$this->skip_deleted ? 'UNDELETED' : '', true)) !== false
			) {
			if (!empty($msg_index)) {
			list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
			$msg_index = array_slice($msg_index, $begin, $end-$begin);
			$is_uid = true;

			if ($slice)
			$msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);

			// fetch reqested headers from server
			$a_msg_headers = $this->fetch_headers($mailbox, $msg_index, true);
			}
			}
			// fetch specified header for all messages and sort
			else if ($msg_index = $this->conn->fetchHeaderIndex($mailbox, "1:*",
			$this->sort_field, $this->skip_deleted)
			) {
			asort($msg_index); // ASC
			$msg_index = array_keys($msg_index);
			list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
			$msg_index = array_slice($msg_index, $begin, $end-$begin);

			if ($slice)
			$msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);

			// fetch reqested headers from server
			$a_msg_headers = $this->fetch_headers($mailbox, $msg_index);
			// use saved message set
			if ($this->search_string && $folder == $this->folder) {
			return $this->list_search_messages($folder, $page, $slice);
			}

			// return empty array if no messages found
			if (!is_array($a_msg_headers) \|\| empty($a_msg_headers))
			if ($this->threading) {
			return $this->list_thread_messages($folder, $page, $slice);
			}

			// get UIDs of all messages in the folder, sorted
			$index = $this->index($folder, $this->sort_field, $this->sort_order);

			if ($index->is_empty()) {
			return array();
			}

			// use this class for message sorting
			$sorter = new rcube_header_sorter();
			$sorter->set_index($msg_index, $is_uid);
			$sorter->sort_headers($a_msg_headers);
			$from = ($page-1) * $this->page_size;
			$to = $from + $this->page_size;

			if ($this->sort_order == 'DESC' && !$sorted)
			$a_msg_headers = array_reverse($a_msg_headers);
			$index->slice($from, $to - $from);

			if ($slice) {
			$index->slice(-$slice, $slice);
			}

			// fetch reqested messages headers
			$a_index = $index->get();
			$a_msg_headers = $this->fetch_headers($folder, $a_index);

			return array_values($a_msg_headers);
			}


			/**
			* Private method for listing message headers using threads
			* protected method for listing message headers using threads
			*
			* @param string $mailbox Mailbox/folder name
			* @param string $folder Folder name
			* @param int $page Current page to list
			* @param string $sort_field Header field to sort by
			* @param string $sort_order Sort order [ASC\|DESC]
			* @param int $slice Number of slice items to extract from result array
			*
			* @return array Indexed array with message header objects
			* @see rcube_imap::list_headers
			* @see rcube_imap::list_messages
			*/
			private function _list_thread_headers($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			protected function list_thread_messages($folder, $page, $slice=0)
			{
			$this->_set_sort_order($sort_field, $sort_order);

			$page = $page ? $page : $this->list_page;
			$mcache = $this->get_mcache_engine();

			// get all threads (not sorted)
			if ($mcache)
			list ($thread_tree, $msg_depth, $has_children) = $mcache->get_thread($mailbox);
			else
			list ($thread_tree, $msg_depth, $has_children) = $this->fetch_threads($mailbox);
			if ($mcache = $this->get_mcache_engine()) {
			$threads = $mcache->get_thread($folder);
			}
			else {
			$threads = $this->fetch_threads($folder);
			}

			if (empty($thread_tree))
			return array();

			$msg_index = $this->sort_threads($mailbox, $thread_tree);

			return $this->_fetch_thread_headers($mailbox,
			$thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice);
			return $this->fetch_thread_headers($folder, $threads, $page, $slice);
			}


			/**
			* Method for fetching threads data
			*
			* @param string $mailbox Folder name
			* @param bool $force Use IMAP server, no cache
			* @param string $folder Folder name
			* @param bool $force Use IMAP server, no cache
			*
			* @return array Array with thread data
			* @return rcube_imap_thread Thread data object
			*/
			function fetch_threads($mailbox, $force = false)
			function fetch_threads($folder, $force = false)
			{
			if (!$force && ($mcache = $this->get_mcache_engine())) {
			// don't store in self's internal cache, cache has it's own internal cache
			return $mcache->get_thread($mailbox);
			return $mcache->get_thread($folder);
			}

			if (empty($this->icache['threads'])) {
			if (!$this->check_connection()) {
			return new rcube_result_thread();
			}

			// get all threads
			$result = $this->conn->thread($mailbox, $this->threading,
			$this->skip_deleted ? 'UNDELETED' : '');
			$result = $this->conn->thread($folder, $this->threading,
			$this->options['skip_deleted'] ? 'UNDELETED' : '', true);

			// add to internal (fast) cache
			$this->icache['threads'] = array();
			$this->icache['threads']['tree'] = is_array($result) ? $result[0] : array();
			$this->icache['threads']['depth'] = is_array($result) ? $result[1] : array();
			$this->icache['threads']['has_children'] = is_array($result) ? $result[2] : array();
			$this->icache['threads'] = $result;
			}

			return array(
			$this->icache['threads']['tree'],
			$this->icache['threads']['depth'],
			$this->icache['threads']['has_children'],
			);
			return $this->icache['threads'];
			}


			/**
			* Private method for fetching threaded messages headers
			* protected method for fetching threaded messages headers
			*
			* @param string $mailbox Mailbox name
			* @param array $thread_tree Thread tree data
			* @param array $msg_depth Thread depth data
			* @param array $has_children Thread children data
			* @param array $msg_index Messages index
			* @param int $page List page number
			* @param int $slice Number of threads to slice
			* @param string $folder Folder name
			* @param rcube_result_thread $threads Threads data object
			* @param int $page List page number
			* @param int $slice Number of threads to slice
			*
			* @return array Messages headers
			* @access private
			*/
			private function _fetch_thread_headers($mailbox, $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0)
			protected function fetch_thread_headers($folder, $threads, $page, $slice=0)
			{
			// now get IDs for current page
			list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
			$msg_index = array_slice($msg_index, $begin, $end-$begin);
			// Sort thread structure
			$this->sort_threads($threads);

			if ($slice)
			$msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
			$from = ($page-1) * $this->page_size;
			$to = $from + $this->page_size;

			if ($this->sort_order == 'DESC')
			$msg_index = array_reverse($msg_index);
			$threads->slice($from, $to - $from);

			// flatten threads array
			// @TODO: fetch children only in expanded mode (?)
			$all_ids = array();
			foreach ($msg_index as $root) {
			$all_ids[] = $root;
			if (!empty($thread_tree[$root]))
			$all_ids = array_merge($all_ids, array_keys_recursive($thread_tree[$root]));
			if ($slice) {
			$threads->slice(-$slice, $slice);
			}

			// Get UIDs of all messages in all threads
			$a_index = $threads->get();

			// fetch reqested headers from server
			$a_msg_headers = $this->fetch_headers($mailbox, $all_ids);
			$a_msg_headers = $this->fetch_headers($folder, $a_index);

			// return empty array if no messages found
			if (!is_array($a_msg_headers) \|\| empty($a_msg_headers))
			return array();

			// use this class for message sorting
			$sorter = new rcube_header_sorter();
			$sorter->set_index($all_ids);
			$sorter->sort_headers($a_msg_headers);
			unset($a_index);

			// Set depth, has_children and unread_children fields in headers
			$this->_set_thread_flags($a_msg_headers, $msg_depth, $has_children);
			$this->set_thread_flags($a_msg_headers, $threads);

			return array_values($a_msg_headers);
			}


			/**
			* Private method for setting threaded messages flags:
			* protected method for setting threaded messages flags:
			* depth, has_children and unread_children
			*
			* @param array $headers Reference to headers array indexed by message ID
			* @param array $msg_depth Array of messages depth indexed by message ID
			* @param array $msg_children Array of messages children flags indexed by message ID
			* @return array Message headers array indexed by message ID
			* @access private
			* @param array $headers Reference to headers array indexed by message UID
			* @param rcube_result_thread $threads Threads data object
			*
			* @return array Message headers array indexed by message UID
			*/
			private function _set_thread_flags(&$headers, $msg_depth, $msg_children)
			protected function set_thread_flags(&$headers, $threads)
			{
			$parents = array();

			foreach ($headers as $idx => $header) {
			$id = $header->id;
			$depth = $msg_depth[$id];
			list ($msg_depth, $msg_children) = $threads->get_thread_data();

			foreach ($headers as $uid => $header) {
			$depth = $msg_depth[$uid];
			$parents = array_slice($parents, 0, $depth);

			if (!empty($parents)) {
			$headers[$idx]->parent_uid = end($parents);
			$headers[$uid]->parent_uid = end($parents);
			if (empty($header->flags['SEEN']))
			$headers[$parents[0]]->unread_children++;
			}
			array_push($parents, $header->uid);
			array_push($parents, $uid);

			$headers[$idx]->depth = $depth;
			$headers[$idx]->has_children = $msg_children[$id];
			$headers[$uid]->depth = $depth;
			$headers[$uid]->has_children = $msg_children[$uid];
			}
			}


			/**
			* Private method for listing a set of message headers (search results)
			* protected method for listing a set of message headers (search results)
			*
			* @param string $mailbox Mailbox/folder name
			* @param int $page Current page to list
			* @param string $sort_field Header field to sort by
			* @param string $sort_order Sort order [ASC\|DESC]
			* @param int $slice Number of slice items to extract from result array
			* @param string $folder Folder name
			* @param int $page Current page to list
			* @param int $slice Number of slice items to extract from result array
			*
			* @return array Indexed array with message header objects
			* @access private
			* @see rcube_imap::list_header_set()
			*/
			private function _list_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			protected function list_search_messages($folder, $page, $slice=0)
			{
			if (!strlen($mailbox) \|\| empty($this->search_set))
			if (!strlen($folder) \|\| empty($this->search_set) \|\| $this->search_set->is_empty()) {
			return array();
			}

			// use saved messages from searching
			if ($this->threading)
			return $this->_list_thread_header_set($mailbox, $page, $sort_field, $sort_order, $slice);
			if ($this->threading) {
			return $this->list_search_thread_messages($folder, $page, $slice);
			}

			// search set is threaded, we need a new one
			if ($this->search_threads) {
			if (empty($this->search_set['tree']))
			return array();
			$this->search('', $this->search_string, $this->search_charset, $sort_field);
			$this->search('', $this->search_string, $this->search_charset, $this->sort_field);
			}

			$msgs = $this->search_set;
			$a_msg_headers = array();
			$page = $page ? $page : $this->list_page;
			$start_msg = ($page-1) * $this->page_size;
			$index = clone $this->search_set;
			$from = ($page-1) * $this->page_size;
			$to = $from + $this->page_size;

			$this->_set_sort_order($sort_field, $sort_order);
			// return empty array if no messages found
			if ($index->is_empty()) {
			return array();
			}

			// quickest method (default sorting)
			if (!$this->search_sort_field && !$this->sort_field) {
			if ($sort_order == 'DESC')
			$msgs = array_reverse($msgs);
			$got_index = true;
			}
			// sorted messages, so we can first slice array and then fetch only wanted headers
			else if ($this->search_sorted) { // SORT searching result
			$got_index = true;
			// reset search set if sorting field has been changed
			if ($this->sort_field && $this->search_sort_field != $this->sort_field) {
			$this->search('', $this->search_string, $this->search_charset, $this->sort_field);

			$index = clone $this->search_set;

			// return empty array if no messages found
			if ($index->is_empty()) {
			return array();
			}
			}
			}

			if ($got_index) {
			if ($this->sort_order != $index->get_parameters('ORDER')) {
			$index->revert();
			}

			// get messages uids for one page
			$msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));
			$index->slice($from, $to-$from);

			if ($slice)
			$msgs = array_slice($msgs, -$slice, $slice);
			if ($slice) {
			$index->slice(-$slice, $slice);
			}

			// fetch headers
			$a_msg_headers = $this->fetch_headers($mailbox, $msgs);

			// I didn't found in RFC that FETCH always returns messages sorted by index
			$sorter = new rcube_header_sorter();
			$sorter->set_index($msgs);
			$sorter->sort_headers($a_msg_headers);
			$a_index = $index->get();
			$a_msg_headers = $this->fetch_headers($folder, $a_index);

			return array_values($a_msg_headers);
			}

			// sorted messages, so we can first slice array and then fetch only wanted headers
			if ($this->search_sorted) { // SORT searching result
			// reset search set if sorting field has been changed
			if ($this->sort_field && $this->search_sort_field != $this->sort_field)
			$msgs = $this->search('', $this->search_string, $this->search_charset, $this->sort_field);
			// SEARCH result, need sorting
			$cnt = $index->count();

			// 300: experimantal value for best result
			if (($cnt > 300 && $cnt > $this->page_size) \|\| !$this->sort_field) {
			// use memory less expensive (and quick) method for big result set
			$index = clone $this->index('', $this->sort_field, $this->sort_order);
			// get messages uids for one page...
			$index->slice($start_msg, min($cnt-$from, $this->page_size));

			if ($slice) {
			$index->slice(-$slice, $slice);
			}

			// ...and fetch headers
			$a_index = $index->get();
			$a_msg_headers = $this->fetch_headers($folder, $a_index);

			return array_values($a_msg_headers);
			}
			else {
			// for small result set we can fetch all messages headers
			$a_index = $index->get();
			$a_msg_headers = $this->fetch_headers($folder, $a_index, false);

			// return empty array if no messages found
			if (empty($msgs))
			if (!is_array($a_msg_headers) \|\| empty($a_msg_headers)) {
			return array();

			if ($sort_order == 'DESC')
			$msgs = array_reverse($msgs);

			// get messages uids for one page
			$msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));

			if ($slice)
			$msgs = array_slice($msgs, -$slice, $slice);

			// fetch headers
			$a_msg_headers = $this->fetch_headers($mailbox, $msgs);

			$sorter = new rcube_header_sorter();
			$sorter->set_index($msgs);
			$sorter->sort_headers($a_msg_headers);

			return array_values($a_msg_headers);
			}
			else { // SEARCH result, need sorting
			$cnt = count($msgs);
			// 300: experimantal value for best result
			if (($cnt > 300 && $cnt > $this->page_size) \|\| !$this->sort_field) {
			// use memory less expensive (and quick) method for big result set
			$a_index = $this->message_index('', $this->sort_field, $this->sort_order);
			// get messages uids for one page...
			$msgs = array_slice($a_index, $start_msg, min($cnt-$start_msg, $this->page_size));
			if ($slice)
			$msgs = array_slice($msgs, -$slice, $slice);
			// ...and fetch headers
			$a_msg_headers = $this->fetch_headers($mailbox, $msgs);


			// return empty array if no messages found
			if (!is_array($a_msg_headers) \|\| empty($a_msg_headers))
			return array();

			$sorter = new rcube_header_sorter();
			$sorter->set_index($msgs);
			$sorter->sort_headers($a_msg_headers);

			return array_values($a_msg_headers);
			}
			else {
			// for small result set we can fetch all messages headers
			$a_msg_headers = $this->fetch_headers($mailbox, $msgs);

			// return empty array if no messages found
			if (!is_array($a_msg_headers) \|\| empty($a_msg_headers))
			return array();

			// if not already sorted
			$a_msg_headers = $this->conn->sortHeaders(
			$a_msg_headers, $this->sort_field, $this->sort_order);

			// only return the requested part of the set
			$a_msg_headers = array_slice(array_values($a_msg_headers),
			$start_msg, min($cnt-$start_msg, $this->page_size));

			if ($slice)
			$a_msg_headers = array_slice($a_msg_headers, -$slice, $slice);

			return $a_msg_headers;
			if (!$this->check_connection()) {
			return array();
			}

			// if not already sorted
			$a_msg_headers = $this->conn->sortHeaders(
			$a_msg_headers, $this->sort_field, $this->sort_order);

			// only return the requested part of the set
			$a_msg_headers = array_slice(array_values($a_msg_headers),
			$from, min($cnt-$to, $this->page_size));

			if ($slice) {
			$a_msg_headers = array_slice($a_msg_headers, -$slice, $slice);
			}

			return $a_msg_headers;
			}
			}


			/**
			* Private method for listing a set of threaded message headers (search results)
			* protected method for listing a set of threaded message headers (search results)
			*
			* @param string $mailbox Mailbox/folder name
			* @param string $folder Folder name
			* @param int $page Current page to list
			* @param string $sort_field Header field to sort by
			* @param string $sort_order Sort order [ASC\|DESC]
			* @param int $slice Number of slice items to extract from result array
			*
			* @return array Indexed array with message header objects
			* @access private
			* @see rcube_imap::list_header_set()
			* @see rcube_imap::list_search_messages()
			*/
			private function _list_thread_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			protected function list_search_thread_messages($folder, $page, $slice=0)
			{
			// update search_set if previous data was fetched with disabled threading
			if (!$this->search_threads) {
			if (empty($this->search_set))
			if ($this->search_set->is_empty()) {
			return array();
			$this->search('', $this->search_string, $this->search_charset, $sort_field);
			}
			$this->search('', $this->search_string, $this->search_charset, $this->sort_field);
			}

			// empty result
			if (empty($this->search_set['tree']))
			return array();

			$thread_tree = $this->search_set['tree'];
			$msg_depth = $this->search_set['depth'];
			$has_children = $this->search_set['children'];
			$a_msg_headers = array();

			$page = $page ? $page : $this->list_page;
			$start_msg = ($page-1) * $this->page_size;

			$this->_set_sort_order($sort_field, $sort_order);

			$msg_index = $this->sort_threads($mailbox, $thread_tree, array_keys($msg_depth));

			return $this->_fetch_thread_headers($mailbox,
			$thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0);
			return $this->fetch_thread_headers($folder, clone $this->search_set, $page, $slice);
			}


			/**
			* Helper function to get first and last index of the requested set
			* Fetches messages headers (by UID)
			*
			* @param int $max Messages count
			* @param mixed $page Page number to show, or string 'all'
			* @return array Array with two values: first index, last index
			* @access private
			*/
			private function _get_message_range($max, $page)
			{
			$start_msg = ($page-1) * $this->page_size;

			if ($page=='all') {
			$begin = 0;
			$end = $max;
			}
			else if ($this->sort_order=='DESC') {
			$begin = $max - $this->page_size - $start_msg;
			$end = $max - $start_msg;
			}
			else {
			$begin = $start_msg;
			$end = $start_msg + $this->page_size;
			}

			if ($begin < 0) $begin = 0;
			if ($end < 0) $end = $max;
			if ($end > $max) $end = $max;

			return array($begin, $end);
			}


			/**
			* Fetches messages headers
			*
			* @param string $mailbox Mailbox name
			* @param array $msgs Messages sequence numbers
			* @param bool $is_uid Enable if $msgs numbers are UIDs
			* @param string $folder Folder name
			* @param array $msgs Message UIDs
			* @param bool $sort Enables result sorting by $msgs
			* @param bool $force Disables cache use
			*
			* @return array Messages headers indexed by UID
			* @access private
			*/
			function fetch_headers($mailbox, $msgs, $is_uid = false, $force = false)
			function fetch_headers($folder, $msgs, $sort = true, $force = false)
			{
			if (empty($msgs))
			if (empty($msgs)) {
			return array();

			if (!$force && ($mcache = $this->get_mcache_engine())) {
			return $mcache->get_messages($mailbox, $msgs, $is_uid);
			}

			// fetch reqested headers from server
			$index = $this->conn->fetchHeaders(
			$mailbox, $msgs, $is_uid, false, $this->get_fetch_headers());

			if (empty($index))
			if (!$force && ($mcache = $this->get_mcache_engine())) {
			$headers = $mcache->get_messages($folder, $msgs);
			}
			else if (!$this->check_connection()) {
			return array();
			}
			else {
			// fetch reqested headers from server
			$headers = $this->conn->fetchHeaders(
			$folder, $msgs, true, false, $this->get_fetch_headers());
			}

			foreach ($index as $headers) {
			$a_msg_headers[$headers->uid] = $headers;
			if (empty($headers)) {
			return array();
			}

			foreach ($headers as $h) {
			$a_msg_headers[$h->uid] = $h;
			}

			if ($sort) {
			// use this class for message sorting
			$sorter = new rcube_message_header_sorter();
			$sorter->set_index($msgs);
			$sorter->sort_headers($a_msg_headers);
			}

			return $a_msg_headers;
			@@ -1354,23 +1058,24 @@


			/**
			* Returns current status of mailbox
			* Returns current status of folder
			*
			* We compare the maximum UID to determine the number of
			* new messages because the RECENT flag is not reliable.
			*
			* @param string $mailbox Mailbox/folder name
			* @param string $folder Folder name
			*
			* @return int Folder status
			*/
			function mailbox_status($mailbox = null)
			public function folder_status($folder = null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}
			$old = $this->get_folder_stats($mailbox);
			$old = $this->get_folder_stats($folder);

			// refresh message count -> will update
			$this->_messagecount($mailbox, 'ALL', true);
			$this->countmessages($folder, 'ALL', true);

			$result = 0;

			@@ -1378,14 +1083,16 @@
			return $result;
			}

			$new = $this->get_folder_stats($mailbox);
			$new = $this->get_folder_stats($folder);

			// got new messages
			if ($new['maxuid'] > $old['maxuid'])
			if ($new['maxuid'] > $old['maxuid']) {
			$result += 1;
			}
			// some messages has been deleted
			if ($new['cnt'] < $old['cnt'])
			if ($new['cnt'] < $old['cnt']) {
			$result += 2;
			}

			// @TODO: optional checking for messages flags changes (?)
			// @TODO: UIDVALIDITY checking
			@@ -1398,362 +1105,337 @@
			* Stores folder statistic data in session
			* @TODO: move to separate DB table (cache?)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param string $name Data name
			* @param mixed $data Data value
			*/
			private function set_folder_stats($mailbox, $name, $data)
			protected function set_folder_stats($folder, $name, $data)
			{
			$_SESSION['folders'][$mailbox][$name] = $data;
			$_SESSION['folders'][$folder][$name] = $data;
			}


			/**
			* Gets folder statistic data
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			*
			* @return array Stats data
			*/
			private function get_folder_stats($mailbox)
			protected function get_folder_stats($folder)
			{
			if ($_SESSION['folders'][$mailbox])
			return (array) $_SESSION['folders'][$mailbox];
			else
			return array();
			if ($_SESSION['folders'][$folder]) {
			return (array) $_SESSION['folders'][$folder];
			}

			return array();
			}


			/**
			* Return sorted array of message IDs (not UIDs)
			* Return sorted list of message UIDs
			*
			* @param string $mailbox Mailbox to get index from
			* @param string $folder Folder to get index from
			* @param string $sort_field Sort column
			* @param string $sort_order Sort order [ASC, DESC]
			* @return array Indexed array with message IDs
			*
			* @return rcube_result_index\|rcube_result_thread List of messages (UIDs)
			*/
			function message_index($mailbox='', $sort_field=NULL, $sort_order=NULL)
			public function index($folder = '', $sort_field = NULL, $sort_order = NULL)
			{
			if ($this->threading)
			return $this->thread_index($mailbox, $sort_field, $sort_order);

			$this->_set_sort_order($sort_field, $sort_order);

			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if ($this->threading) {
			return $this->thread_index($folder, $sort_field, $sort_order);
			}
			$key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.msgi";

			$this->set_sort_order($sort_field, $sort_order);

			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			// we have a saved search result, get index from there
			if (!isset($this->icache[$key]) && $this->search_string
			&& !$this->search_threads && $mailbox == $this->mailbox) {
			// use message index sort as default sorting
			if (!$this->sort_field) {
			$msgs = $this->search_set;

			if ($this->search_sort_field != 'date')
			sort($msgs);

			if ($this->sort_order == 'DESC')
			$this->icache[$key] = array_reverse($msgs);
			else
			$this->icache[$key] = $msgs;
			if ($this->search_string) {
			if ($this->search_threads) {
			$this->search($folder, $this->search_string, $this->search_charset, $this->sort_field);
			}
			// sort with SORT command
			else if ($this->search_sorted) {
			if ($this->sort_field && $this->search_sort_field != $this->sort_field)
			$this->search('', $this->search_string, $this->search_charset, $this->sort_field);

			if ($this->sort_order == 'DESC')
			$this->icache[$key] = array_reverse($this->search_set);
			else
			$this->icache[$key] = $this->search_set;
			// use message index sort as default sorting
			if (!$this->sort_field \|\| $this->search_sorted) {
			if ($this->sort_field && $this->search_sort_field != $this->sort_field) {
			$this->search($folder, $this->search_string, $this->search_charset, $this->sort_field);
			}
			$index = $this->search_set;
			}
			else if (!$this->check_connection()) {
			return new rcube_result_index();
			}
			else {
			$a_index = $this->conn->fetchHeaderIndex($mailbox,
			join(',', $this->search_set), $this->sort_field, $this->skip_deleted);

			if (is_array($a_index)) {
			if ($this->sort_order=="ASC")
			asort($a_index);
			else if ($this->sort_order=="DESC")
			arsort($a_index);

			$this->icache[$key] = array_keys($a_index);
			}
			else {
			$this->icache[$key] = array();
			}
			$index = $this->conn->index($folder, $this->search_set->get(),
			$this->sort_field, $this->options['skip_deleted'], true, true);
			}
			}

			// have stored it in RAM
			if (isset($this->icache[$key]))
			return $this->icache[$key];
			if ($this->sort_order != $index->get_parameters('ORDER')) {
			$index->revert();
			}

			return $index;
			}

			// check local cache
			if ($mcache = $this->get_mcache_engine()) {
			$a_index = $mcache->get_index($mailbox, $this->sort_field, $this->sort_order);
			$this->icache[$key] = array_keys($a_index);
			$index = $mcache->get_index($folder, $this->sort_field, $this->sort_order);
			}
			// fetch from IMAP server
			else {
			$this->icache[$key] = $this->message_index_direct(
			$mailbox, $this->sort_field, $this->sort_order);
			$index = $this->index_direct(
			$folder, $this->sort_field, $this->sort_order);
			}

			return $this->icache[$key];
			return $index;
			}


			/**
			* Return sorted array of message IDs (not UIDs) directly from IMAP server.
			* Doesn't use cache and ignores current search settings.
			* Return sorted list of message UIDs ignoring current search settings.
			* Doesn't uses cache by default.
			*
			* @param string $mailbox Mailbox to get index from
			* @param string $folder Folder to get index from
			* @param string $sort_field Sort column
			* @param string $sort_order Sort order [ASC, DESC]
			* @param bool $skip_cache Disables cache usage
			*
			* @return array Indexed array with message IDs
			* @return rcube_result_index Sorted list of message UIDs
			*/
			function message_index_direct($mailbox, $sort_field = null, $sort_order = null)
			public function index_direct($folder, $sort_field = null, $sort_order = null, $skip_cache = true)
			{
			if (!$skip_cache && ($mcache = $this->get_mcache_engine())) {
			$index = $mcache->get_index($folder, $sort_field, $sort_order);
			}
			// use message index sort as default sorting
			if (!$sort_field) {
			if ($this->skip_deleted) {
			$a_index = $this->conn->search($mailbox, 'ALL UNDELETED');
			// I didn't found that SEARCH should return sorted IDs
			if (is_array($a_index))
			sort($a_index);
			} else if ($max = $this->_messagecount($mailbox, 'ALL', true, false)) {
			$a_index = range(1, $max);
			else if (!$sort_field) {
			if ($this->options['skip_deleted'] && !empty($this->icache['undeleted_idx'])
			&& $this->icache['undeleted_idx']->get_parameters('MAILBOX') == $folder
			) {
			$index = $this->icache['undeleted_idx'];
			}

			if ($a_index !== false && $sort_order == 'DESC')
			$a_index = array_reverse($a_index);
			else if (!$this->check_connection()) {
			return new rcube_result_index();
			}
			else {
			$index = $this->conn->search($folder,
			'ALL' .($this->options['skip_deleted'] ? ' UNDELETED' : ''), true);
			}
			}
			else if (!$this->check_connection()) {
			return new rcube_result_index();
			}
			// fetch complete message index
			else if ($this->get_capability('SORT') &&
			($a_index = $this->conn->sort($mailbox,
			$sort_field, $this->skip_deleted ? 'UNDELETED' : '')) !== false
			) {
			if ($sort_order == 'DESC')
			$a_index = array_reverse($a_index);
			}
			else if ($a_index = $this->conn->fetchHeaderIndex(
			$mailbox, "1:*", $sort_field, $skip_deleted)) {
			if ($sort_order=="ASC")
			asort($a_index);
			else if ($sort_order=="DESC")
			arsort($a_index);
			else {
			if ($this->get_capability('SORT')) {
			$index = $this->conn->sort($folder, $sort_field,
			$this->options['skip_deleted'] ? 'UNDELETED' : '', true);
			}

			$a_index = array_keys($a_index);
			}

			return $a_index !== false ? $a_index : array();
			}


			/**
			* Return sorted array of threaded message IDs (not UIDs)
			*
			* @param string $mailbox Mailbox to get index from
			* @param string $sort_field Sort column
			* @param string $sort_order Sort order [ASC, DESC]
			* @return array Indexed array with message IDs
			*/
			function thread_index($mailbox='', $sort_field=NULL, $sort_order=NULL)
			{
			$this->_set_sort_order($sort_field, $sort_order);

			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}
			$key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.thi";

			// we have a saved search result, get index from there
			if (!isset($this->icache[$key]) && $this->search_string
			&& $this->search_threads && $mailbox == $this->mailbox) {
			// use message IDs for better performance
			$ids = array_keys_recursive($this->search_set['tree']);
			$this->icache[$key] = $this->_flatten_threads($mailbox, $this->search_set['tree'], $ids);
			}

			// have stored it in RAM
			if (isset($this->icache[$key]))
			return $this->icache[$key];

			// get all threads (default sort order)
			list ($thread_tree) = $this->fetch_threads($mailbox);

			$this->icache[$key] = $this->_flatten_threads($mailbox, $thread_tree);

			return $this->icache[$key];
			}


			/**
			* Return array of threaded messages (all, not only roots)
			*
			* @param string $mailbox Mailbox to get index from
			* @param array $thread_tree Threaded messages array (see fetch_threads())
			* @param array $ids Message IDs if we know what we need (e.g. search result)
			* for better performance
			* @return array Indexed array with message IDs
			*
			* @access private
			*/
			private function _flatten_threads($mailbox, $thread_tree, $ids=null)
			{
			if (empty($thread_tree))
			return array();

			$msg_index = $this->sort_threads($mailbox, $thread_tree, $ids);

			if ($this->sort_order == 'DESC')
			$msg_index = array_reverse($msg_index);

			// flatten threads array
			$all_ids = array();
			foreach ($msg_index as $root) {
			$all_ids[] = $root;
			if (!empty($thread_tree[$root])) {
			foreach (array_keys_recursive($thread_tree[$root]) as $val)
			$all_ids[] = $val;
			if (empty($index) \|\| $index->is_error()) {
			$index = $this->conn->index($folder, "1:*", $sort_field,
			$this->options['skip_deleted'], false, true);
			}
			}

			return $all_ids;
			if ($sort_order != $index->get_parameters('ORDER')) {
			$index->revert();
			}

			return $index;
			}


			/**
			* Return index of threaded message UIDs
			*
			* @param string $folder Folder to get index from
			* @param string $sort_field Sort column
			* @param string $sort_order Sort order [ASC, DESC]
			*
			* @return rcube_result_thread Message UIDs
			*/
			public function thread_index($folder='', $sort_field=NULL, $sort_order=NULL)
			{
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			// we have a saved search result, get index from there
			if ($this->search_string && $this->search_threads && $folder == $this->folder) {
			$threads = $this->search_set;
			}
			else {
			// get all threads (default sort order)
			$threads = $this->fetch_threads($folder);
			}

			$this->set_sort_order($sort_field, $sort_order);
			$this->sort_threads($threads);

			return $threads;
			}


			/**
			* Sort threaded result, using THREAD=REFS method
			*
			* @param rcube_result_thread $threads Threads result set
			*/
			protected function sort_threads($threads)
			{
			if ($threads->is_empty()) {
			return;
			}

			// THREAD=ORDEREDSUBJECT: sorting by sent date of root message
			// THREAD=REFERENCES: sorting by sent date of root message
			// THREAD=REFS: sorting by the most recent date in each thread

			if ($this->sort_field && ($this->sort_field != 'date' \|\| $this->get_capability('THREAD') != 'REFS')) {
			$index = $this->index_direct($this->folder, $this->sort_field, $this->sort_order, false);

			if (!$index->is_empty()) {
			$threads->sort($index);
			}
			}
			else {
			if ($this->sort_order != $threads->get_parameters('ORDER')) {
			$threads->revert();
			}
			}
			}


			/**
			* Invoke search request to IMAP server
			*
			* @param string $mailbox Mailbox name to search in
			* @param string $folder Folder name to search in
			* @param string $str Search criteria
			* @param string $charset Search charset
			* @param string $sort_field Header field to sort by
			* @return array search results as list of message IDs
			* @access public
			*
			* @todo: Search criteria should be provided in non-IMAP format, eg. array
			*/
			function search($mailbox='', $str=NULL, $charset=NULL, $sort_field=NULL)
			public function search($folder='', $str='ALL', $charset=NULL, $sort_field=NULL)
			{
			if (!$str)
			return false;

			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!$str) {
			$str = 'ALL';
			}

			$results = $this->_search_index($mailbox, $str, $charset, $sort_field);
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			$this->set_search_set($str, $results, $charset, $sort_field, (bool)$this->threading,
			$this->threading \|\| $this->search_sorted ? true : false);
			$results = $this->search_index($folder, $str, $charset, $sort_field);

			return $results;
			$this->set_search_set(array($str, $results, $charset, $sort_field,
			$this->threading \|\| $this->search_sorted ? true : false));
			}


			/**
			* Private search method
			* Direct (real and simple) SEARCH request (without result sorting and caching).
			*
			* @param string $mailbox Mailbox name
			* @param string $mailbox Mailbox name to search in
			* @param string $str Search string
			*
			* @return rcube_result_index Search result (UIDs)
			*/
			public function search_once($folder = null, $str = 'ALL')
			{
			if (!$str) {
			return 'ALL';
			}

			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			if (!$this->check_connection()) {
			return new rcube_result_index();
			}

			$index = $this->conn->search($folder, $str, true);

			return $index;
			}


			/**
			* protected search method
			*
			* @param string $folder Folder name
			* @param string $criteria Search criteria
			* @param string $charset Charset
			* @param string $sort_field Sorting field
			*
			* @return array search results as list of message ids
			* @return rcube_result_index\|rcube_result_thread Search results (UIDs)
			* @see rcube_imap::search()
			*/
			private function _search_index($mailbox, $criteria='ALL', $charset=NULL, $sort_field=NULL)
			protected function search_index($folder, $criteria='ALL', $charset=NULL, $sort_field=NULL)
			{
			$orig_criteria = $criteria;

			if ($this->skip_deleted && !preg_match('/UNDELETED/', $criteria))
			if (!$this->check_connection()) {
			if ($this->threading) {
			return new rcube_result_thread();
			}
			else {
			return new rcube_result_index();
			}
			}

			if ($this->options['skip_deleted'] && !preg_match('/UNDELETED/', $criteria)) {
			$criteria = 'UNDELETED '.$criteria;
			}

			if ($this->threading) {
			$a_messages = $this->conn->thread($mailbox, $this->threading, $criteria, $charset);
			$threads = $this->conn->thread($folder, $this->threading, $criteria, true, $charset);

			// Error, try with US-ASCII (RFC5256: SORT/THREAD must support US-ASCII and UTF-8,
			// but I've seen that Courier doesn't support UTF-8)
			if ($a_messages === false && $charset && $charset != 'US-ASCII')
			$a_messages = $this->conn->thread($mailbox, $this->threading,
			$this->convert_criteria($criteria, $charset), 'US-ASCII');

			if ($a_messages !== false) {
			list ($thread_tree, $msg_depth, $has_children) = $a_messages;
			$a_messages = array(
			'tree' => $thread_tree,
			'depth'=> $msg_depth,
			'children' => $has_children
			);
			if ($threads->is_error() && $charset && $charset != 'US-ASCII') {
			$threads = $this->conn->thread($folder, $this->threading,
			$this->convert_criteria($criteria, $charset), true, 'US-ASCII');
			}

			return $a_messages;
			return $threads;
			}

			if ($sort_field && $this->get_capability('SORT')) {
			$charset = $charset ? $charset : $this->default_charset;
			$a_messages = $this->conn->sort($mailbox, $sort_field, $criteria, false, $charset);
			$charset = $charset ? $charset : $this->default_charset;
			$messages = $this->conn->sort($folder, $sort_field, $criteria, true, $charset);

			// Error, try with US-ASCII (RFC5256: SORT/THREAD must support US-ASCII and UTF-8,
			// but I've seen Courier with disabled UTF-8 support)
			if ($a_messages === false && $charset && $charset != 'US-ASCII')
			$a_messages = $this->conn->sort($mailbox, $sort_field,
			$this->convert_criteria($criteria, $charset), false, 'US-ASCII');
			if ($messages->is_error() && $charset && $charset != 'US-ASCII') {
			$messages = $this->conn->sort($folder, $sort_field,
			$this->convert_criteria($criteria, $charset), true, 'US-ASCII');
			}

			if ($a_messages !== false) {
			if (!$messages->is_error()) {
			$this->search_sorted = true;
			return $a_messages;
			return $messages;
			}
			}

			if ($orig_criteria == 'ALL') {
			$max = $this->_messagecount($mailbox, 'ALL', true, false);
			$a_messages = $max ? range(1, $max) : array();
			}
			else {
			$a_messages = $this->conn->search($mailbox,
			($charset ? "CHARSET $charset " : '') . $criteria);
			$messages = $this->conn->search($folder,
			($charset ? "CHARSET $charset " : '') . $criteria, true);

			// Error, try with US-ASCII (some servers may support only US-ASCII)
			if ($a_messages === false && $charset && $charset != 'US-ASCII')
			$a_messages = $this->conn->search($mailbox,
			'CHARSET US-ASCII ' . $this->convert_criteria($criteria, $charset));

			// I didn't found that SEARCH should return sorted IDs
			if (is_array($a_messages) && !$this->sort_field)
			sort($a_messages);
			// Error, try with US-ASCII (some servers may support only US-ASCII)
			if ($messages->is_error() && $charset && $charset != 'US-ASCII') {
			$messages = $this->conn->search($folder,
			$this->convert_criteria($criteria, $charset), true);
			}

			$this->search_sorted = false;

			return $a_messages;
			}


			/**
			* Direct (real and simple) SEARCH request to IMAP server,
			* without result sorting and caching
			*
			* @param string $mailbox Mailbox name to search in
			* @param string $str Search string
			* @param boolean $ret_uid True if UIDs should be returned
			*
			* @return array Search results as list of message IDs or UIDs
			*/
			function search_once($mailbox='', $str=NULL, $ret_uid=false)
			{
			if (!$str)
			return false;

			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			return $this->conn->search($mailbox, $str, $ret_uid);
			return $messages;
			}


			@@ -1763,10 +1445,10 @@
			* @param string $str Search string
			* @param string $charset Original charset
			* @param string $dest_charset Destination charset (default US-ASCII)
			*
			* @return string Search string
			* @access private
			*/
			private function convert_criteria($str, $charset, $dest_charset='US-ASCII')
			protected function convert_criteria($str, $charset, $dest_charset='US-ASCII')
			{
			// convert strings to US_ASCII
			if (preg_match_all('/\{([0-9]+)\}\r\n/', $str, $matches, PREG_OFFSET_CAPTURE)) {
			@@ -1774,122 +1456,23 @@
			foreach ($matches[1] as $m) {
			$string_offset = $m[1] + strlen($m[0]) + 4; // {}\r\n
			$string = substr($str, $string_offset - 1, $m[0]);
			$string = rcube_charset_convert($string, $charset, $dest_charset);
			if (!$string)
			$string = rcube_charset::convert($string, $charset, $dest_charset);
			if ($string === false) {
			continue;
			$res .= sprintf("%s{%d}\r\n%s", substr($str, $last, $m[1] - $last - 1), strlen($string), $string);
			}
			$res .= substr($str, $last, $m[1] - $last - 1) . rcube_imap_generic::escape($string);
			$last = $m[0] + $string_offset - 1;
			}
			if ($last < strlen($str))
			if ($last < strlen($str)) {
			$res .= substr($str, $last, strlen($str)-$last);
			}
			}
			else // strings for conversion not found
			// strings for conversion not found
			else {
			$res = $str;
			}

			return $res;
			}


			/**
			* Sort thread
			*
			* @param string $mailbox Mailbox name
			* @param array $thread_tree Unsorted thread tree (rcube_imap_generic::thread() result)
			* @param array $ids Message IDs if we know what we need (e.g. search result)
			*
			* @return array Sorted roots IDs
			*/
			function sort_threads($mailbox, $thread_tree, $ids = null)
			{
			// THREAD=ORDEREDSUBJECT: sorting by sent date of root message
			// THREAD=REFERENCES: sorting by sent date of root message
			// THREAD=REFS: sorting by the most recent date in each thread

			// default sorting
			if (!$this->sort_field \|\| ($this->sort_field == 'date' && $this->threading == 'REFS')) {
			return array_keys((array)$thread_tree);
			}
			// here we'll implement REFS sorting
			else {
			if ($mcache = $this->get_mcache_engine()) {
			$a_index = $mcache->get_index($mailbox, $this->sort_field, 'ASC');
			if (is_array($a_index)) {
			$a_index = array_keys($a_index);
			// now we must remove IDs that doesn't exist in $ids
			if (!empty($ids))
			$a_index = array_intersect($a_index, $ids);
			}
			}
			// use SORT command
			else if ($this->get_capability('SORT') &&
			($a_index = $this->conn->sort($mailbox, $this->sort_field,
			!empty($ids) ? $ids : ($this->skip_deleted ? 'UNDELETED' : ''))) !== false
			) {
			// do nothing
			}
			else {
			// fetch specified headers for all messages and sort them
			$a_index = $this->conn->fetchHeaderIndex($mailbox, !empty($ids) ? $ids : "1:*",
			$this->sort_field, $this->skip_deleted);

			// return unsorted tree if we've got no index data
			if (!empty($a_index)) {
			asort($a_index); // ASC
			$a_index = array_values($a_index);
			}
			}

			if (empty($a_index))
			return array_keys((array)$thread_tree);

			return $this->_sort_thread_refs($thread_tree, $a_index);
			}
			}


			/**
			* THREAD=REFS sorting implementation
			*
			* @param array $tree Thread tree array (message identifiers as keys)
			* @param array $index Array of sorted message identifiers
			*
			* @return array Array of sorted roots messages
			*/
			private function _sort_thread_refs($tree, $index)
			{
			if (empty($tree))
			return array();

			$index = array_combine(array_values($index), $index);

			// assign roots
			foreach ($tree as $idx => $val) {
			$index[$idx] = $idx;
			if (!empty($val)) {
			$idx_arr = array_keys_recursive($tree[$idx]);
			foreach ($idx_arr as $subidx)
			$index[$subidx] = $idx;
			}
			}

			$index = array_values($index);

			// create sorted array of roots
			$msg_index = array();
			if ($this->sort_order != 'DESC') {
			foreach ($index as $idx)
			if (!isset($msg_index[$idx]))
			$msg_index[$idx] = $idx;
			$msg_index = array_values($msg_index);
			}
			else {
			for ($x=count($index)-1; $x>=0; $x--)
			if (!isset($msg_index[$index[$x]]))
			$msg_index[$index[$x]] = $index[$x];
			$msg_index = array_reverse($msg_index);
			}

			return $msg_index;
			}


			@@ -1898,57 +1481,41 @@
			*
			* @return array Current search set
			*/
			function refresh_search()
			public function refresh_search()
			{
			if (!empty($this->search_string))
			$this->search_set = $this->search('', $this->search_string, $this->search_charset,
			$this->search_sort_field, $this->search_threads, $this->search_sorted);
			if (!empty($this->search_string)) {
			$this->search('', $this->search_string, $this->search_charset, $this->search_sort_field);
			}

			return $this->get_search_set();
			}


			/**
			* Check if the given message ID is part of the current search set
			*
			* @param string $msgid Message id
			* @return boolean True on match or if no search request is stored
			*/
			function in_searchset($msgid)
			{
			if (!empty($this->search_string)) {
			if ($this->search_threads)
			return isset($this->search_set['depth']["$msgid"]);
			else
			return in_array("$msgid", (array)$this->search_set, true);
			}
			else
			return true;
			}


			/**
			* Return message headers object of a specific message
			*
			* @param int $id Message sequence ID or UID
			* @param string $mailbox Mailbox to read from
			* @param int $id Message UID
			* @param string $folder Folder to read from
			* @param bool $force True to skip cache
			*
			* @return rcube_mail_header Message headers
			* @return rcube_message_header Message headers
			*/
			function get_headers($uid, $mailbox = null, $force = false)
			public function get_message_headers($uid, $folder = null, $force = false)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			// get cached headers
			if (!$force && $uid && ($mcache = $this->get_mcache_engine())) {
			$headers = $mcache->get_message($mailbox, $uid);
			$headers = $mcache->get_message($folder, $uid);
			}
			else if (!$this->check_connection()) {
			$headers = false;
			}
			else {
			$headers = $this->conn->fetchHeader(
			$mailbox, $uid, true, true, $this->get_fetch_headers());
			$folder, $uid, true, true, $this->get_fetch_headers());
			}

			return $headers;
			@@ -1960,14 +1527,14 @@
			* an object structure similar to the one generated by PEAR::Mail_mimeDecode
			*
			* @param int $uid Message UID to fetch
			* @param string $mailbox Mailbox to read from
			* @param string $folder Folder to read from
			*
			* @return object rcube_mail_header Message data
			* @return object rcube_message_header Message data
			*/
			function get_message($uid, $mailbox = null)
			public function get_message($uid, $folder = null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			// Check internal cache
			@@ -1977,32 +1544,41 @@
			}
			}

			$headers = $this->get_headers($uid, $mailbox);
			$headers = $this->get_message_headers($uid, $folder);

			// message doesn't exist?
			if (empty($headers))
			return null;
			if (empty($headers)) {
			return null;
			}

			// structure might be cached
			if (!empty($headers->structure))
			if (!empty($headers->structure)) {
			return $headers;
			}

			$this->_msg_uid = $uid;
			$this->msg_uid = $uid;

			if (!$this->check_connection()) {
			return $headers;
			}

			if (empty($headers->bodystructure)) {
			$headers->bodystructure = $this->conn->getStructure($mailbox, $uid, true);
			$headers->bodystructure = $this->conn->getStructure($folder, $uid, true);
			}

			$structure = $headers->bodystructure;

			if (empty($structure))
			if (empty($structure)) {
			return $headers;
			}

			// set message charset from message headers
			if ($headers->charset)
			if ($headers->charset) {
			$this->struct_charset = $headers->charset;
			else
			$this->struct_charset = $this->_structure_charset($structure);
			}
			else {
			$this->struct_charset = $this->structure_charset($structure);
			}

			$headers->ctype = strtolower($headers->ctype);

			@@ -2018,11 +1594,12 @@
			$structure[0] = $m[1];
			$structure[1] = $m[2];
			}
			else
			else {
			return $headers;
			}
			}

			$struct = &$this->_structure_part($structure, 0, '', $headers);
			$struct = $this->structure_part($structure, 0, '', $headers);

			// don't trust given content-type
			if (empty($struct->parts) && !empty($headers->ctype)) {
			@@ -2043,9 +1620,8 @@
			* @param array $part
			* @param int $count
			* @param string $parent
			* @access private
			*/
			function &_structure_part($part, $count=0, $parent='', $mime_headers=null)
			protected function structure_part($part, $count=0, $parent='', $mime_headers=null)
			{
			$struct = new rcube_message_part;
			$struct->mime_id = empty($parent) ? (string)$count : "$parent.$count";
			@@ -2078,8 +1654,9 @@

			// build parts list for headers pre-fetching
			for ($i=0; $i<count($part); $i++) {
			if (!is_array($part[$i]))
			if (!is_array($part[$i])) {
			break;
			}
			// fetch message headers if message/rfc822
			// or named part (could contain Content-Location header)
			if (!is_array($part[$i][0])) {
			@@ -2097,16 +1674,17 @@
			// @TODO: we could do this before _structure_part() call, to fetch
			// headers for parts on all levels
			if ($mime_part_headers) {
			$mime_part_headers = $this->conn->fetchMIMEHeaders($this->mailbox,
			$this->_msg_uid, $mime_part_headers);
			$mime_part_headers = $this->conn->fetchMIMEHeaders($this->folder,
			$this->msg_uid, $mime_part_headers);
			}

			$struct->parts = array();
			for ($i=0, $count=0; $i<count($part); $i++) {
			if (!is_array($part[$i]))
			if (!is_array($part[$i])) {
			break;
			}
			$tmp_part_id = $struct->mime_id ? $struct->mime_id.'.'.($i+1) : $i+1;
			$struct->parts[] = $this->_structure_part($part[$i], ++$count, $struct->mime_id,
			$struct->parts[] = $this->structure_part($part[$i], ++$count, $struct->mime_id,
			$mime_part_headers[$tmp_part_id]);
			}

			@@ -2142,11 +1720,13 @@
			// read content type parameters
			if (is_array($part[2])) {
			$struct->ctype_parameters = array();
			for ($i=0; $i<count($part[2]); $i+=2)
			for ($i=0; $i<count($part[2]); $i+=2) {
			$struct->ctype_parameters[strtolower($part[2][$i])] = $part[2][$i+1];
			}

			if (isset($struct->ctype_parameters['charset']))
			if (isset($struct->ctype_parameters['charset'])) {
			$struct->charset = $struct->ctype_parameters['charset'];
			}
			}

			// #1487700: workaround for lack of charset in malformed structure
			@@ -2161,29 +1741,37 @@
			}

			// get part size
			if (!empty($part[6]))
			if (!empty($part[6])) {
			$struct->size = intval($part[6]);
			}

			// read part disposition
			$di = 8;
			if ($struct->ctype_primary == 'text') $di += 1;
			else if ($struct->mimetype == 'message/rfc822') $di += 3;
			if ($struct->ctype_primary == 'text') {
			$di += 1;
			}
			else if ($struct->mimetype == 'message/rfc822') {
			$di += 3;
			}

			if (is_array($part[$di]) && count($part[$di]) == 2) {
			$struct->disposition = strtolower($part[$di][0]);

			if (is_array($part[$di][1]))
			for ($n=0; $n<count($part[$di][1]); $n+=2)
			if (is_array($part[$di][1])) {
			for ($n=0; $n<count($part[$di][1]); $n+=2) {
			$struct->d_parameters[strtolower($part[$di][1][$n])] = $part[$di][1][$n+1];
			}
			}
			}

			// get message/rfc822's child-parts
			if (is_array($part[8]) && $di != 8) {
			$struct->parts = array();
			for ($i=0, $count=0; $i<count($part[8]); $i++) {
			if (!is_array($part[8][$i]))
			if (!is_array($part[8][$i])) {
			break;
			$struct->parts[] = $this->_structure_part($part[8][$i], ++$count, $struct->mime_id);
			}
			$struct->parts[] = $this->structure_part($part[8][$i], ++$count, $struct->mime_id);
			}
			}

			@@ -2192,44 +1780,51 @@
			$struct->content_id = $part[3];
			$struct->headers['content-id'] = $part[3];

			if (empty($struct->disposition))
			if (empty($struct->disposition)) {
			$struct->disposition = 'inline';
			}
			}

			// fetch message headers if message/rfc822 or named part (could contain Content-Location header)
			if ($struct->ctype_primary == 'message' \|\| ($struct->ctype_parameters['name'] && !$struct->content_id)) {
			if (empty($mime_headers)) {
			$mime_headers = $this->conn->fetchPartHeader(
			$this->mailbox, $this->_msg_uid, true, $struct->mime_id);
			$this->folder, $this->msg_uid, true, $struct->mime_id);
			}

			if (is_string($mime_headers))
			$struct->headers = $this->_parse_headers($mime_headers) + $struct->headers;
			else if (is_object($mime_headers))
			if (is_string($mime_headers)) {
			$struct->headers = rcube_mime::parse_headers($mime_headers) + $struct->headers;
			}
			else if (is_object($mime_headers)) {
			$struct->headers = get_object_vars($mime_headers) + $struct->headers;
			}

			// get real content-type of message/rfc822
			if ($struct->mimetype == 'message/rfc822') {
			// single-part
			if (!is_array($part[8][0]))
			if (!is_array($part[8][0])) {
			$struct->real_mimetype = strtolower($part[8][0] . '/' . $part[8][1]);
			}
			// multi-part
			else {
			for ($n=0; $n<count($part[8]); $n++)
			if (!is_array($part[8][$n]))
			for ($n=0; $n<count($part[8]); $n++) {
			if (!is_array($part[8][$n])) {
			break;
			}
			}
			$struct->real_mimetype = 'multipart/' . strtolower($part[8][$n]);
			}
			}

			if ($struct->ctype_primary == 'message' && empty($struct->parts)) {
			if (is_array($part[8]) && $di != 8)
			$struct->parts[] = $this->_structure_part($part[8], ++$count, $struct->mime_id);
			if (is_array($part[8]) && $di != 8) {
			$struct->parts[] = $this->structure_part($part[8], ++$count, $struct->mime_id);
			}
			}
			}

			// normalize filename property
			$this->_set_part_filename($struct, $mime_headers);
			$this->set_part_filename($struct, $mime_headers);

			return $struct;
			}
			@@ -2240,16 +1835,18 @@
			*
			* @param rcube_message_part $part Part object
			* @param string $headers Part's raw headers
			* @access private
			*/
			private function _set_part_filename(&$part, $headers=null)
			protected function set_part_filename(&$part, $headers=null)
			{
			if (!empty($part->d_parameters['filename']))
			if (!empty($part->d_parameters['filename'])) {
			$filename_mime = $part->d_parameters['filename'];
			else if (!empty($part->d_parameters['filename*']))
			}
			else if (!empty($part->d_parameters['filename*'])) {
			$filename_encoded = $part->d_parameters['filename*'];
			else if (!empty($part->ctype_parameters['name*']))
			}
			else if (!empty($part->ctype_parameters['name*'])) {
			$filename_encoded = $part->ctype_parameters['name*'];
			}
			// RFC2231 value continuations
			// TODO: this should be rewrited to support RFC2231 4.1 combinations
			else if (!empty($part->d_parameters['filename*0'])) {
			@@ -2263,7 +1860,7 @@
			if ($i<2) {
			if (!$headers) {
			$headers = $this->conn->fetchPartHeader(
			$this->mailbox, $this->_msg_uid, true, $part->mime_id);
			$this->folder, $this->msg_uid, true, $part->mime_id);
			}
			$filename_mime = '';
			$i = 0;
			@@ -2282,7 +1879,7 @@
			if ($i<2) {
			if (!$headers) {
			$headers = $this->conn->fetchPartHeader(
			$this->mailbox, $this->_msg_uid, true, $part->mime_id);
			$this->folder, $this->msg_uid, true, $part->mime_id);
			}
			$filename_encoded = '';
			$i = 0; $matches = array();
			@@ -2301,7 +1898,7 @@
			if ($i<2) {
			if (!$headers) {
			$headers = $this->conn->fetchPartHeader(
			$this->mailbox, $this->_msg_uid, true, $part->mime_id);
			$this->folder, $this->msg_uid, true, $part->mime_id);
			}
			$filename_mime = '';
			$i = 0; $matches = array();
			@@ -2320,7 +1917,7 @@
			if ($i<2) {
			if (!$headers) {
			$headers = $this->conn->fetchPartHeader(
			$this->mailbox, $this->_msg_uid, true, $part->mime_id);
			$this->folder, $this->msg_uid, true, $part->mime_id);
			}
			$filename_encoded = '';
			$i = 0; $matches = array();
			@@ -2331,24 +1928,30 @@
			}
			}
			// read 'name' after rfc2231 parameters as it may contains truncated filename (from Thunderbird)
			else if (!empty($part->ctype_parameters['name']))
			else if (!empty($part->ctype_parameters['name'])) {
			$filename_mime = $part->ctype_parameters['name'];
			}
			// Content-Disposition
			else if (!empty($part->headers['content-description']))
			else if (!empty($part->headers['content-description'])) {
			$filename_mime = $part->headers['content-description'];
			else
			}
			else {
			return;
			}

			// decode filename
			if (!empty($filename_mime)) {
			if (!empty($part->charset))
			if (!empty($part->charset)) {
			$charset = $part->charset;
			else if (!empty($this->struct_charset))
			}
			else if (!empty($this->struct_charset)) {
			$charset = $this->struct_charset;
			else
			$charset = rc_detect_encoding($filename_mime, $this->default_charset);
			}
			else {
			$charset = rcube_charset::detect($filename_mime, $this->default_charset);
			}

			$part->filename = rcube_imap::decode_mime_string($filename_mime, $charset);
			$part->filename = rcube_mime::decode_mime_string($filename_mime, $charset);
			}
			else if (!empty($filename_encoded)) {
			// decode filename according to RFC 2231, Section 4
			@@ -2357,7 +1960,7 @@
			$filename_encoded = $fmatches[2];
			}

			$part->filename = rcube_charset_convert(urldecode($filename_encoded), $filename_charset);
			$part->filename = rcube_charset::convert(urldecode($filename_encoded), $filename_charset);
			}
			}

			@@ -2366,14 +1969,15 @@
			* Get charset name from message structure (first part)
			*
			* @param array $structure Message structure
			*
			* @return string Charset name
			* @access private
			*/
			private function _structure_charset($structure)
			protected function structure_charset($structure)
			{
			while (is_array($structure)) {
			if (is_array($structure[2]) && $structure[2][0] == 'charset')
			if (is_array($structure[2]) && $structure[2][0] == 'charset') {
			return $structure[2][1];
			}
			$structure = $structure[0];
			}
			}
			@@ -2391,11 +1995,15 @@
			*
			* @return string Message/part body if not printed
			*/
			function &get_message_part($uid, $part=1, $o_part=NULL, $print=NULL, $fp=NULL, $skip_charset_conv=false)
			public function get_message_part($uid, $part=1, $o_part=NULL, $print=NULL, $fp=NULL, $skip_charset_conv=false)
			{
			if (!$this->check_connection()) {
			return null;
			}

			// get part data if not provided
			if (!is_object($o_part)) {
			$structure = $this->conn->getStructure($this->mailbox, $uid, true);
			$structure = $this->conn->getStructure($this->folder, $uid, true);
			$part_data = rcube_imap_generic::getStructurePartData($structure, $part);

			$o_part = new rcube_message_part;
			@@ -2406,7 +2014,7 @@
			}

			if ($o_part && $o_part->size) {
			$body = $this->conn->handlePartBody($this->mailbox, $uid, true,
			$body = $this->conn->handlePartBody($this->folder, $uid, true,
			$part ? $part : 'TEXT', $o_part->encoding, $print, $fp);
			}

			@@ -2416,37 +2024,26 @@

			// convert charset (if text or message part)
			if ($body && preg_match('/^(text\|message)$/', $o_part->ctype_primary)) {
			// Remove NULL characters (#1486189)
			$body = str_replace("\x00", '', $body);
			// Remove NULL characters if any (#1486189)
			if (strpos($body, "\x00") !== false) {
			$body = str_replace("\x00", '', $body);
			}

			if (!$skip_charset_conv) {
			if (!$skip_charset_conv) {
			if (!$o_part->charset \|\| strtoupper($o_part->charset) == 'US-ASCII') {
			// try to extract charset information from HTML meta tag (#1488125)
			if ($o_part->ctype_secondary == 'html' && preg_match('/<meta[^>]+charset=([a-z0-9-_]+)/i', $body, $m))
			if ($o_part->ctype_secondary == 'html' && preg_match('/<meta[^>]+charset=([a-z0-9-_]+)/i', $body, $m)) {
			$o_part->charset = strtoupper($m[1]);
			else
			}
			else {
			$o_part->charset = $this->default_charset;
			}
			}
			$body = rcube_charset_convert($body, $o_part->charset);
			$body = rcube_charset::convert($body, $o_part->charset);
			}
			}

			return $body;
			}


			/**
			* Fetch message body of a specific message from the server
			*
			* @param int $uid Message UID
			* @return string $part Message/part body
			* @see rcube_imap::get_message_part()
			*/
			function &get_body($uid, $part=1)
			{
			$headers = $this->get_headers($uid);
			return rcube_charset_convert($this->get_message_part($uid, $part, NULL),
			$headers->charset ? $headers->charset : $this->default_charset);
			}


			@@ -2458,9 +2055,13 @@
			*
			* @return string Message source string
			*/
			function &get_raw_body($uid, $fp=null)
			public function get_raw_body($uid, $fp=null)
			{
			return $this->conn->handlePartBody($this->mailbox, $uid,
			if (!$this->check_connection()) {
			return null;
			}

			return $this->conn->handlePartBody($this->folder, $uid,
			true, null, null, false, $fp);
			}

			@@ -2469,22 +2070,29 @@
			* Returns the message headers as string
			*
			* @param int $uid Message UID
			*
			* @return string Message headers string
			*/
			function &get_raw_headers($uid)
			public function get_raw_headers($uid)
			{
			return $this->conn->fetchPartHeader($this->mailbox, $uid, true);
			if (!$this->check_connection()) {
			return null;
			}

			return $this->conn->fetchPartHeader($this->folder, $uid, true);
			}


			/**
			* Sends the whole message source to stdout
			*
			* @param int $uid Message UID
			*/
			function print_raw_body($uid)
			public function print_raw_body($uid)
			{
			$this->conn->handlePartBody($this->mailbox, $uid, true, NULL, NULL, true);
			if (!$this->check_connection()) {
			return;
			}

			$this->conn->handlePartBody($this->folder, $uid, true, NULL, NULL, true);
			}


			@@ -2493,24 +2101,30 @@
			*
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @param string $flag Flag to set: SEEN, UNDELETED, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			* @param boolean $skip_cache True to skip message cache clean up
			*
			* @return boolean Operation status
			*/
			function set_flag($uids, $flag, $mailbox=null, $skip_cache=false)
			public function set_flag($uids, $flag, $folder=null, $skip_cache=false)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			if (!$this->check_connection()) {
			return false;
			}

			$flag = strtoupper($flag);
			list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
			list($uids, $all_mode) = $this->parse_uids($uids);

			if (strpos($flag, 'UN') === 0)
			$result = $this->conn->unflag($mailbox, $uids, substr($flag, 2));
			else
			$result = $this->conn->flag($mailbox, $uids, $flag);
			if (strpos($flag, 'UN') === 0) {
			$result = $this->conn->unflag($folder, $uids, substr($flag, 2));
			}
			else {
			$result = $this->conn->flag($folder, $uids, $flag);
			}

			if ($result) {
			// reload message headers if cached
			@@ -2518,17 +2132,17 @@
			if (!$skip_cache && ($mcache = $this->get_mcache_engine())) {
			$status = strpos($flag, 'UN') !== 0;
			$mflag = preg_replace('/^UN/', '', $flag);
			$mcache->change_flag($mailbox, $all_mode ? null : explode(',', $uids),
			$mcache->change_flag($folder, $all_mode ? null : explode(',', $uids),
			$mflag, $status);
			}

			// clear cached counters
			if ($flag == 'SEEN' \|\| $flag == 'UNSEEN') {
			$this->_clear_messagecount($mailbox, 'SEEN');
			$this->_clear_messagecount($mailbox, 'UNSEEN');
			$this->clear_messagecount($folder, 'SEEN');
			$this->clear_messagecount($folder, 'UNSEEN');
			}
			else if ($flag == 'DELETED') {
			$this->_clear_messagecount($mailbox, 'DELETED');
			$this->clear_messagecount($folder, 'DELETED');
			}
			}

			@@ -2537,48 +2151,34 @@


			/**
			* Remove message flag for one or several messages
			* Append a mail message (source) to a specific folder
			*
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @param string $flag Flag to unset: SEEN, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
			* @param string $mailbox Folder name
			*
			* @return int Number of flagged messages, -1 on failure
			* @see set_flag
			*/
			function unset_flag($uids, $flag, $mailbox=null)
			{
			return $this->set_flag($uids, 'UN'.$flag, $mailbox);
			}


			/**
			* Append a mail message (source) to a specific mailbox
			*
			* @param string $mailbox Target mailbox
			* @param string $folder Target folder
			* @param string $message The message source string or filename
			* @param string $headers Headers string if $message contains only the body
			* @param boolean $is_file True if $message is a filename
			*
			* @return int\|bool Appended message UID or True on success, False on error
			*/
			function save_message($mailbox, &$message, $headers='', $is_file=false)
			public function save_message($folder, &$message, $headers='', $is_file=false)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			// make sure mailbox exists
			if ($this->mailbox_exists($mailbox)) {
			if ($is_file)
			$saved = $this->conn->appendFromFile($mailbox, $message, $headers);
			else
			$saved = $this->conn->append($mailbox, $message);
			// make sure folder exists
			if ($this->folder_exists($folder)) {
			if ($is_file) {
			$saved = $this->conn->appendFromFile($folder, $message, $headers);
			}
			else {
			$saved = $this->conn->append($folder, $message);
			}
			}

			if ($saved) {
			// increase messagecount of the target mailbox
			$this->_set_messagecount($mailbox, 'ALL', 1);
			// increase messagecount of the target folder
			$this->set_messagecount($folder, 'ALL', 1);
			}

			return $saved;
			@@ -2586,33 +2186,39 @@


			/**
			* Move a message from one mailbox to another
			* Move a message from one folder to another
			*
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @param string $to_mbox Target mailbox
			* @param string $from_mbox Source mailbox
			* @param string $to_mbox Target folder
			* @param string $from_mbox Source folder
			*
			* @return boolean True on success, False on error
			*/
			function move_message($uids, $to_mbox, $from_mbox='')
			public function move_message($uids, $to_mbox, $from_mbox='')
			{
			if (!strlen($from_mbox)) {
			$from_mbox = $this->mailbox;
			$from_mbox = $this->folder;
			}

			if ($to_mbox === $from_mbox) {
			return false;
			}

			list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
			list($uids, $all_mode) = $this->parse_uids($uids);

			// exit if no message uids are specified
			if (empty($uids))
			if (empty($uids)) {
			return false;
			}

			// make sure mailbox exists
			if ($to_mbox != 'INBOX' && !$this->mailbox_exists($to_mbox)) {
			if (!$this->check_connection()) {
			return false;
			}

			// make sure folder exists
			if ($to_mbox != 'INBOX' && !$this->folder_exists($to_mbox)) {
			if (in_array($to_mbox, $this->default_folders)) {
			if (!$this->create_mailbox($to_mbox, true)) {
			if (!$this->create_folder($to_mbox, true)) {
			return false;
			}
			}
			@@ -2621,7 +2227,7 @@
			}
			}

			$config = rcmail::get_instance()->config;
			$config = rcube::get_instance()->config;
			$to_trash = $to_mbox == $config->get('trash_mbox');

			// flag messages as read before moving them
			@@ -2634,11 +2240,11 @@
			$moved = $this->conn->move($uids, $from_mbox, $to_mbox);

			// send expunge command in order to have the moved message
			// really deleted from the source mailbox
			// really deleted from the source folder
			if ($moved) {
			$this->_expunge($from_mbox, false, $uids);
			$this->_clear_messagecount($from_mbox);
			$this->_clear_messagecount($to_mbox);
			$this->expunge_message($uids, $from_mbox, false);
			$this->clear_messagecount($from_mbox);
			$this->clear_messagecount($to_mbox);
			}
			// moving failed
			else if ($to_trash && $config->get('delete_always', false)) {
			@@ -2650,18 +2256,14 @@
			unset($this->icache['threads']);

			// remove message ids from search set
			if ($this->search_set && $from_mbox == $this->mailbox) {
			if ($this->search_set && $from_mbox == $this->folder) {
			// threads are too complicated to just remove messages from set
			if ($this->search_threads \|\| $all_mode)
			if ($this->search_threads \|\| $all_mode) {
			$this->refresh_search();
			else {
			$a_uids = explode(',', $uids);
			foreach ($a_uids as $uid)
			$a_mids[] = $this->uid2id($uid, $from_mbox);
			$this->search_set = array_diff($this->search_set, $a_mids);
			}
			unset($a_mids);
			unset($a_uids);
			else {
			$this->search_set->filter(explode(',', $uids));
			}
			}

			// remove cached messages
			@@ -2674,30 +2276,35 @@


			/**
			* Copy a message from one mailbox to another
			* Copy a message from one folder to another
			*
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @param string $to_mbox Target mailbox
			* @param string $from_mbox Source mailbox
			* @param string $to_mbox Target folder
			* @param string $from_mbox Source folder
			*
			* @return boolean True on success, False on error
			*/
			function copy_message($uids, $to_mbox, $from_mbox='')
			public function copy_message($uids, $to_mbox, $from_mbox='')
			{
			if (!strlen($from_mbox)) {
			$from_mbox = $this->mailbox;
			$from_mbox = $this->folder;
			}

			list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
			list($uids, $all_mode) = $this->parse_uids($uids);

			// exit if no message uids are specified
			if (empty($uids)) {
			return false;
			}

			// make sure mailbox exists
			if ($to_mbox != 'INBOX' && !$this->mailbox_exists($to_mbox)) {
			if (!$this->check_connection()) {
			return false;
			}

			// make sure folder exists
			if ($to_mbox != 'INBOX' && !$this->folder_exists($to_mbox)) {
			if (in_array($to_mbox, $this->default_folders)) {
			if (!$this->create_mailbox($to_mbox, true)) {
			if (!$this->create_folder($to_mbox, true)) {
			return false;
			}
			}
			@@ -2710,7 +2317,7 @@
			$copied = $this->conn->copy($uids, $from_mbox, $to_mbox);

			if ($copied) {
			$this->_clear_messagecount($to_mbox);
			$this->clear_messagecount($to_mbox);
			}

			return $copied;
			@@ -2718,54 +2325,55 @@


			/**
			* Mark messages as deleted and expunge mailbox
			* Mark messages as deleted and expunge them
			*
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @param string $mailbox Source mailbox
			* @param string $folder Source folder
			*
			* @return boolean True on success, False on error
			*/
			function delete_message($uids, $mailbox='')
			public function delete_message($uids, $folder='')
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
			list($uids, $all_mode) = $this->parse_uids($uids);

			// exit if no message uids are specified
			if (empty($uids))
			if (empty($uids)) {
			return false;
			}

			$deleted = $this->conn->delete($mailbox, $uids);
			if (!$this->check_connection()) {
			return false;
			}

			$deleted = $this->conn->flag($folder, $uids, 'DELETED');

			if ($deleted) {
			// send expunge command in order to have the deleted message
			// really deleted from the mailbox
			$this->_expunge($mailbox, false, $uids);
			$this->_clear_messagecount($mailbox);
			unset($this->uid_id_map[$mailbox]);
			// really deleted from the folder
			$this->expunge_message($uids, $folder, false);
			$this->clear_messagecount($folder);
			unset($this->uid_id_map[$folder]);

			// unset threads internal cache
			unset($this->icache['threads']);

			// remove message ids from search set
			if ($this->search_set && $mailbox == $this->mailbox) {
			if ($this->search_set && $folder == $this->folder) {
			// threads are too complicated to just remove messages from set
			if ($this->search_threads \|\| $all_mode)
			if ($this->search_threads \|\| $all_mode) {
			$this->refresh_search();
			}
			else {
			$a_uids = explode(',', $uids);
			foreach ($a_uids as $uid)
			$a_mids[] = $this->uid2id($uid, $mailbox);
			$this->search_set = array_diff($this->search_set, $a_mids);
			unset($a_uids);
			unset($a_mids);
			$this->search_set->filter(explode(',', $uids));
			}
			}

			// remove cached messages
			$this->clear_message_cache($mailbox, $all_mode ? null : explode(',', $uids));
			$this->clear_message_cache($folder, $all_mode ? null : explode(',', $uids));
			}

			return $deleted;
			@@ -2773,175 +2381,59 @@


			/**
			* Clear all messages in a specific mailbox
			*
			* @param string $mailbox Mailbox name
			*
			* @return int Above 0 on success
			*/
			function clear_mailbox($mailbox=null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			// SELECT will set messages count for clearFolder()
			if ($this->conn->select($mailbox)) {
			$cleared = $this->conn->clearFolder($mailbox);
			}

			// make sure the cache is cleared as well
			if ($cleared) {
			$this->clear_message_cache($mailbox);
			$a_mailbox_cache = $this->get_cache('messagecount');
			unset($a_mailbox_cache[$mailbox]);
			$this->update_cache('messagecount', $a_mailbox_cache);
			}

			return $cleared;
			}


			/**
			* Send IMAP expunge command and clear cache
			*
			* @param string $mailbox Mailbox name
			* @param boolean $clear_cache False if cache should not be cleared
			*
			* @return boolean True on success
			*/
			function expunge($mailbox='', $clear_cache=true)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			return $this->_expunge($mailbox, $clear_cache);
			}


			/**
			* Send IMAP expunge command and clear cache
			*
			* @param string $mailbox Mailbox name
			* @param boolean $clear_cache False if cache should not be cleared
			* @param mixed $uids Message UIDs as array or comma-separated string, or '*'
			* @return boolean True on success
			* @access private
			* @see rcube_imap::expunge()
			* @param string $folder Folder name
			* @param boolean $clear_cache False if cache should not be cleared
			*
			* @return boolean True on success, False on failure
			*/
			private function _expunge($mailbox, $clear_cache=true, $uids=NULL)
			public function expunge_message($uids, $folder = null, $clear_cache = true)
			{
			if ($uids && $this->get_capability('UIDPLUS'))
			list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
			else
			if ($uids && $this->get_capability('UIDPLUS')) {
			list($uids, $all_mode) = $this->parse_uids($uids);
			}
			else {
			$uids = null;
			}

			// force mailbox selection and check if mailbox is writeable
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			if (!$this->check_connection()) {
			return false;
			}

			// force folder selection and check if folder is writeable
			// to prevent a situation when CLOSE is executed on closed
			// or EXPUNGE on read-only mailbox
			$result = $this->conn->select($mailbox);
			// or EXPUNGE on read-only folder
			$result = $this->conn->select($folder);
			if (!$result) {
			return false;
			}

			if (!$this->conn->data['READ-WRITE']) {
			$this->conn->setError(rcube_imap_generic::ERROR_READONLY, "Mailbox is read-only");
			$this->conn->setError(rcube_imap_generic::ERROR_READONLY, "Folder is read-only");
			return false;
			}

			// CLOSE(+SELECT) should be faster than EXPUNGE
			if (empty($uids) \|\| $all_mode)
			if (empty($uids) \|\| $all_mode) {
			$result = $this->conn->close();
			else
			$result = $this->conn->expunge($mailbox, $uids);
			}
			else {
			$result = $this->conn->expunge($folder, $uids);
			}

			if ($result && $clear_cache) {
			$this->clear_message_cache($mailbox, $all_mode ? null : explode(',', $uids));
			$this->_clear_messagecount($mailbox);
			$this->clear_message_cache($folder, $all_mode ? null : explode(',', $uids));
			$this->clear_messagecount($folder);
			}

			return $result;
			}


			/**
			* Parse message UIDs input
			*
			* @param mixed $uids UIDs array or comma-separated list or '' or '1:'
			* @param string $mailbox Mailbox name
			* @return array Two elements array with UIDs converted to list and ALL flag
			* @access private
			*/
			private function _parse_uids($uids, $mailbox)
			{
			if ($uids === '' \|\| $uids === '1:') {
			if (empty($this->search_set)) {
			$uids = '1:*';
			$all = true;
			}
			// get UIDs from current search set
			// @TODO: skip fetchUIDs() and work with IDs instead of UIDs (?)
			else {
			if ($this->search_threads)
			$uids = $this->conn->fetchUIDs($mailbox, array_keys($this->search_set['depth']));
			else
			$uids = $this->conn->fetchUIDs($mailbox, $this->search_set);

			// save ID-to-UID mapping in local cache
			if (is_array($uids))
			foreach ($uids as $id => $uid)
			$this->uid_id_map[$mailbox][$uid] = $id;

			$uids = join(',', $uids);
			}
			}
			else {
			if (is_array($uids))
			$uids = join(',', $uids);

			if (preg_match('/[^0-9,]/', $uids))
			$uids = '';
			}

			return array($uids, (bool) $all);
			}


			/**
			* Translate UID to message ID
			*
			* @param int $uid Message UID
			* @param string $mailbox Mailbox name
			*
			* @return int Message ID
			*/
			function get_id($uid, $mailbox=null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			return $this->uid2id($uid, $mailbox);
			}


			/**
			* Translate message number to UID
			*
			* @param int $id Message ID
			* @param string $mailbox Mailbox name
			*
			* @return int Message UID
			*/
			function get_uid($id, $mailbox=null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			return $this->id2uid($id, $mailbox);
			}



			/* --------------------------------
			@@ -2949,7 +2441,7 @@
			* --------------------------------*/

			/**
			* Public method for listing subscribed folders
			* Public method for listing subscribed folders.
			*
			* @param string $root Optional root folder
			* @param string $name Optional name pattern
			@@ -2958,9 +2450,8 @@
			* @param bool $skip_sort Enable to return unsorted list (for better performance)
			*
			* @return array List of folders
			* @access public
			*/
			function list_mailboxes($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			public function list_folders_subscribed($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			{
			$cache_key = $root.':'.$name;
			if (!empty($filter)) {
			@@ -2975,7 +2466,7 @@
			return $a_mboxes;
			}

			$a_mboxes = $this->_list_mailboxes($root, $name, $filter, $rights);
			$a_mboxes = $this->_list_folders_subscribed($root, $name, $filter, $rights);

			if (!is_array($a_mboxes)) {
			return array();
			@@ -2991,12 +2482,12 @@
			array_unshift($a_mboxes, 'INBOX');
			}

			// sort mailboxes (always sort for cache)
			// sort folders (always sort for cache)
			if (!$skip_sort \|\| $this->cache) {
			$a_mboxes = $this->_sort_mailbox_list($a_mboxes);
			$a_mboxes = $this->sort_folder_list($a_mboxes);
			}

			// write mailboxlist to cache
			// write folders list to cache
			$this->update_cache($cache_key, $a_mboxes);

			return $a_mboxes;
			@@ -3004,44 +2495,44 @@


			/**
			* Private method for mailbox listing
			* protected method for folders listing (LSUB)
			*
			* @param string $root Optional root folder
			* @param string $name Optional name pattern
			* @param mixed $filter Optional filter
			* @param string $rights Optional ACL requirements
			*
			* @return array List of mailboxes/folders
			* @see rcube_imap::list_mailboxes()
			* @access private
			* @return array List of subscribed folders
			* @see rcube_imap::list_folders_subscribed()
			*/
			private function _list_mailboxes($root='', $name='*', $filter=null, $rights=null)
			protected function _list_folders_subscribed($root='', $name='*', $filter=null, $rights=null)
			{
			$a_defaults = $a_out = array();

			// Give plugins a chance to provide a list of mailboxes
			$data = rcmail::get_instance()->plugins->exec_hook('mailboxes_list',
			// Give plugins a chance to provide a list of folders
			$data = rcube::get_instance()->plugins->exec_hook('storage_folders',
			array('root' => $root, 'name' => $name, 'filter' => $filter, 'mode' => 'LSUB'));

			if (isset($data['folders'])) {
			$a_folders = $data['folders'];
			}
			else if (!$this->conn->connected()) {
			else if (!$this->check_connection()) {
			return null;
			}
			else {
			// Server supports LIST-EXTENDED, we can use selection options
			$config = rcmail::get_instance()->config;
			$config = rcube::get_instance()->config;
			// #1486225: Some dovecot versions returns wrong result using LIST-EXTENDED
			if (!$config->get('imap_force_lsub') && $this->get_capability('LIST-EXTENDED')) {
			// This will also set mailbox options, LSUB doesn't do that
			// This will also set folder options, LSUB doesn't do that
			$a_folders = $this->conn->listMailboxes($root, $name,
			NULL, array('SUBSCRIBED'));

			// unsubscribe non-existent folders, remove from the list
			if (is_array($a_folders) && $name == '*') {
			// we can do this only when LIST response is available
			if (is_array($a_folders) && $name == '*' && !empty($this->conn->data['LIST'])) {
			foreach ($a_folders as $idx => $folder) {
			if ($this->conn->data['LIST'] && ($opts = $this->conn->data['LIST'][$folder])
			if (($opts = $this->conn->data['LIST'][$folder])
			&& in_array('\\NonExistent', $opts)
			) {
			$this->conn->unsubscribe($folder);
			@@ -3054,14 +2545,15 @@
			else {
			$a_folders = $this->conn->listSubscribed($root, $name);

			// unsubscribe non-existent folders, remove from the list
			if (is_array($a_folders) && $name == '*') {
			// unsubscribe non-existent folders, remove them from the list,
			// we can do this only when LIST response is available
			if (is_array($a_folders) && $name == '*' && !empty($this->conn->data['LIST'])) {
			foreach ($a_folders as $idx => $folder) {
			if ($this->conn->data['LIST'] && ($opts = $this->conn->data['LIST'][$folder])
			&& in_array('\\Noselect', $opts)
			if (!isset($this->conn->data['LIST'][$folder])
			\|\| in_array('\\Noselect', $this->conn->data['LIST'][$folder])
			) {
			// Some servers returns \Noselect for existing folders
			if (!$this->mailbox_exists($folder)) {
			if (!$this->folder_exists($folder)) {
			$this->conn->unsubscribe($folder);
			unset($a_folders[$idx]);
			}
			@@ -3080,7 +2572,7 @@


			/**
			* Get a list of all folders available on the IMAP server
			* Get a list of all folders available on the server
			*
			* @param string $root IMAP root dir
			* @param string $name Optional name pattern
			@@ -3090,7 +2582,7 @@
			*
			* @return array Indexed array with folder names
			*/
			function list_unsubscribed($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			public function list_folders($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			{
			$cache_key = $root.':'.$name;
			if (!empty($filter)) {
			@@ -3105,8 +2597,8 @@
			return $a_mboxes;
			}

			// Give plugins a chance to provide a list of mailboxes
			$data = rcmail::get_instance()->plugins->exec_hook('mailboxes_list',
			// Give plugins a chance to provide a list of folders
			$data = rcube::get_instance()->plugins->exec_hook('storage_folders',
			array('root' => $root, 'name' => $name, 'filter' => $filter, 'mode' => 'LIST'));

			if (isset($data['folders'])) {
			@@ -3114,7 +2606,7 @@
			}
			else {
			// retrieve list of folders from IMAP server
			$a_mboxes = $this->conn->listMailboxes($root, $name);
			$a_mboxes = $this->_list_folders($root, $name);
			}

			if (!is_array($a_mboxes)) {
			@@ -3127,7 +2619,7 @@
			}

			// cache folder attributes
			if ($root == '' && $name == '*' && empty($filter)) {
			if ($root == '' && $name == '*' && empty($filter) && !empty($this->conn->data)) {
			$this->update_cache('mailboxes.attributes', $this->conn->data['LIST']);
			}

			@@ -3138,10 +2630,10 @@

			// filter folders and sort them
			if (!$skip_sort) {
			$a_mboxes = $this->_sort_mailbox_list($a_mboxes);
			$a_mboxes = $this->sort_folder_list($a_mboxes);
			}

			// write mailboxlist to cache
			// write folders list to cache
			$this->update_cache($cache_key, $a_mboxes);

			return $a_mboxes;
			@@ -3149,15 +2641,84 @@


			/**
			* protected method for folders listing (LIST)
			*
			* @param string $root Optional root folder
			* @param string $name Optional name pattern
			*
			* @return array List of folders
			* @see rcube_imap::list_folders()
			*/
			protected function _list_folders($root='', $name='*')
			{
			if (!$this->check_connection()) {
			return null;
			}

			$result = $this->conn->listMailboxes($root, $name);

			if (!is_array($result)) {
			return array();
			}

			// #1486796: some server configurations doesn't
			// return folders in all namespaces, we'll try to detect that situation
			// and ask for these namespaces separately
			if ($root == '' && $name == '*') {
			$delim = $this->get_hierarchy_delimiter();
			$namespace = $this->get_namespace();
			$search = array();

			// build list of namespace prefixes
			foreach ((array)$namespace as $ns) {
			if (is_array($ns)) {
			foreach ($ns as $ns_data) {
			if (strlen($ns_data[0])) {
			$search[] = $ns_data[0];
			}
			}
			}
			}

			if (!empty($search)) {
			// go through all folders detecting namespace usage
			foreach ($result as $folder) {
			foreach ($search as $idx => $prefix) {
			if (strpos($folder, $prefix) === 0) {
			unset($search[$idx]);
			}
			}
			if (empty($search)) {
			break;
			}
			}

			// get folders in hidden namespaces and add to the result
			foreach ($search as $prefix) {
			$list = $this->conn->listMailboxes($prefix, $name);

			if (!empty($list)) {
			$result = array_merge($result, $list);
			}
			}
			}
			}

			return $result;
			}


			/**
			* Filter the given list of folders according to access rights
			*/
			private function filter_rights($a_folders, $rights)
			protected function filter_rights($a_folders, $rights)
			{
			$regex = '/('.$rights.')/';
			foreach ($a_folders as $idx => $folder) {
			$myrights = join('', (array)$this->my_rights($folder));
			if ($myrights !== null && !preg_match($regex, $myrights))
			if ($myrights !== null && !preg_match($regex, $myrights)) {
			unset($a_folders[$idx]);
			}
			}

			return $a_folders;
			@@ -3170,85 +2731,92 @@
			*
			* @return mixed Quota info or False if not supported
			*/
			function get_quota()
			public function get_quota()
			{
			if ($this->get_capability('QUOTA'))
			if ($this->get_capability('QUOTA') && $this->check_connection()) {
			return $this->conn->getQuota();
			}

			return false;
			}


			/**
			* Get mailbox size (size of all messages in a mailbox)
			* Get folder size (size of all messages in a folder)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			*
			* @return int Mailbox size in bytes, False on error
			* @return int Folder size in bytes, False on error
			*/
			function get_mailbox_size($mailbox)
			public function folder_size($folder)
			{
			// @TODO: could we try to use QUOTA here?
			$result = $this->conn->fetchHeaderIndex($mailbox, '1:*', 'SIZE', false);
			if (!$this->check_connection()) {
			return 0;
			}

			if (is_array($result))
			// @TODO: could we try to use QUOTA here?
			$result = $this->conn->fetchHeaderIndex($folder, '1:*', 'SIZE', false);

			if (is_array($result)) {
			$result = array_sum($result);
			}

			return $result;
			}


			/**
			* Subscribe to a specific mailbox(es)
			* Subscribe to a specific folder(s)
			*
			* @param array $a_mboxes Mailbox name(s)
			* @param array $folders Folder name(s)
			*
			* @return boolean True on success
			*/
			function subscribe($a_mboxes)
			public function subscribe($folders)
			{
			if (!is_array($a_mboxes))
			$a_mboxes = array($a_mboxes);

			// let this common function do the main work
			return $this->_change_subscription($a_mboxes, 'subscribe');
			return $this->change_subscription($folders, 'subscribe');
			}


			/**
			* Unsubscribe mailboxes
			* Unsubscribe folder(s)
			*
			* @param array $a_mboxes Mailbox name(s)
			* @param array $a_mboxes Folder name(s)
			*
			* @return boolean True on success
			*/
			function unsubscribe($a_mboxes)
			public function unsubscribe($folders)
			{
			if (!is_array($a_mboxes))
			$a_mboxes = array($a_mboxes);

			// let this common function do the main work
			return $this->_change_subscription($a_mboxes, 'unsubscribe');
			return $this->change_subscription($folders, 'unsubscribe');
			}


			/**
			* Create a new mailbox on the server and register it in local cache
			* Create a new folder on the server and register it in local cache
			*
			* @param string $mailbox New mailbox name
			* @param boolean $subscribe True if the new mailbox should be subscribed
			* @param string $folder New folder name
			* @param boolean $subscribe True if the new folder should be subscribed
			*
			* @return boolean True on success
			*/
			function create_mailbox($mailbox, $subscribe=false)
			public function create_folder($folder, $subscribe=false)
			{
			$result = $this->conn->createFolder($mailbox);
			if (!$this->check_connection()) {
			return false;
			}

			$result = $this->conn->createFolder($folder);

			// try to subscribe it
			if ($result) {
			// clear cache
			$this->clear_cache('mailboxes', true);

			if ($subscribe)
			$this->subscribe($mailbox);
			if ($subscribe) {
			$this->subscribe($folder);
			}
			}

			return $result;
			@@ -3256,45 +2824,49 @@


			/**
			* Set a new name to an existing mailbox
			* Set a new name to an existing folder
			*
			* @param string $mailbox Mailbox to rename
			* @param string $new_name New mailbox name
			* @param string $folder Folder to rename
			* @param string $new_name New folder name
			*
			* @return boolean True on success
			*/
			function rename_mailbox($mailbox, $new_name)
			public function rename_folder($folder, $new_name)
			{
			if (!strlen($new_name)) {
			return false;
			}

			if (!$this->check_connection()) {
			return false;
			}

			$delm = $this->get_hierarchy_delimiter();

			// get list of subscribed folders
			if ((strpos($mailbox, '%') === false) && (strpos($mailbox, '*') === false)) {
			$a_subscribed = $this->_list_mailboxes('', $mailbox . $delm . '*');
			$subscribed = $this->mailbox_exists($mailbox, true);
			if ((strpos($folder, '%') === false) && (strpos($folder, '*') === false)) {
			$a_subscribed = $this->_list_folders_subscribed('', $folder . $delm . '*');
			$subscribed = $this->folder_exists($folder, true);
			}
			else {
			$a_subscribed = $this->_list_mailboxes();
			$subscribed = in_array($mailbox, $a_subscribed);
			$a_subscribed = $this->_list_folders_subscribed();
			$subscribed = in_array($folder, $a_subscribed);
			}

			$result = $this->conn->renameFolder($mailbox, $new_name);
			$result = $this->conn->renameFolder($folder, $new_name);

			if ($result) {
			// unsubscribe the old folder, subscribe the new one
			if ($subscribed) {
			$this->conn->unsubscribe($mailbox);
			$this->conn->unsubscribe($folder);
			$this->conn->subscribe($new_name);
			}

			// check if mailbox children are subscribed
			// check if folder children are subscribed
			foreach ($a_subscribed as $c_subscribed) {
			if (preg_match('/^'.preg_quote($mailbox.$delm, '/').'/', $c_subscribed)) {
			if (strpos($c_subscribed, $folder.$delm) === 0) {
			$this->conn->unsubscribe($c_subscribed);
			$this->conn->subscribe(preg_replace('/^'.preg_quote($mailbox, '/').'/',
			$this->conn->subscribe(preg_replace('/^'.preg_quote($folder, '/').'/',
			$new_name, $c_subscribed));

			// clear cache
			@@ -3303,7 +2875,7 @@
			}

			// clear cache
			$this->clear_message_cache($mailbox);
			$this->clear_message_cache($folder);
			$this->clear_cache('mailboxes', true);
			}

			@@ -3312,31 +2884,37 @@


			/**
			* Remove mailbox from server
			* Remove folder from server
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			*
			* @return boolean True on success
			*/
			function delete_mailbox($mailbox)
			function delete_folder($folder)
			{
			$delm = $this->get_hierarchy_delimiter();

			if (!$this->check_connection()) {
			return false;
			}

			// get list of folders
			if ((strpos($mailbox, '%') === false) && (strpos($mailbox, '*') === false))
			$sub_mboxes = $this->list_unsubscribed('', $mailbox . $delm . '*');
			else
			$sub_mboxes = $this->list_unsubscribed();
			if ((strpos($folder, '%') === false) && (strpos($folder, '*') === false)) {
			$sub_mboxes = $this->list_folders('', $folder . $delm . '*');
			}
			else {
			$sub_mboxes = $this->list_folders();
			}

			// send delete command to server
			$result = $this->conn->deleteFolder($mailbox);
			$result = $this->conn->deleteFolder($folder);

			if ($result) {
			// unsubscribe mailbox
			$this->conn->unsubscribe($mailbox);
			// unsubscribe folder
			$this->conn->unsubscribe($folder);

			foreach ($sub_mboxes as $c_mbox) {
			if (preg_match('/^'.preg_quote($mailbox.$delm, '/').'/', $c_mbox)) {
			if (strpos($c_mbox, $folder.$delm) === 0) {
			$this->conn->unsubscribe($c_mbox);
			if ($this->conn->deleteFolder($c_mbox)) {
			$this->clear_message_cache($c_mbox);
			@@ -3344,8 +2922,8 @@
			}
			}

			// clear mailbox-related cache
			$this->clear_message_cache($mailbox);
			// clear folder-related cache
			$this->clear_message_cache($folder);
			$this->clear_cache('mailboxes', true);
			}

			@@ -3356,14 +2934,16 @@
			/**
			* Create all folders specified as default
			*/
			function create_default_folders()
			public function create_default_folders()
			{
			// create default folders if they do not exist
			foreach ($this->default_folders as $folder) {
			if (!$this->mailbox_exists($folder))
			$this->create_mailbox($folder, true);
			else if (!$this->mailbox_exists($folder, true))
			if (!$this->folder_exists($folder)) {
			$this->create_folder($folder, true);
			}
			else if (!$this->folder_exists($folder, true)) {
			$this->subscribe($folder);
			}
			}
			}

			@@ -3371,31 +2951,36 @@
			/**
			* Checks if folder exists and is subscribed
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			* @param boolean $subscription Enable subscription checking
			*
			* @return boolean TRUE or FALSE
			*/
			function mailbox_exists($mailbox, $subscription=false)
			public function folder_exists($folder, $subscription=false)
			{
			if ($mailbox == 'INBOX') {
			if ($folder == 'INBOX') {
			return true;
			}

			$key = $subscription ? 'subscribed' : 'existing';

			if (is_array($this->icache[$key]) && in_array($mailbox, $this->icache[$key]))
			if (is_array($this->icache[$key]) && in_array($folder, $this->icache[$key])) {
			return true;
			}

			if (!$this->check_connection()) {
			return false;
			}

			if ($subscription) {
			$a_folders = $this->conn->listSubscribed('', $mailbox);
			$a_folders = $this->conn->listSubscribed('', $folder);
			}
			else {
			$a_folders = $this->conn->listMailboxes('', $mailbox);
			$a_folders = $this->conn->listMailboxes('', $folder);
			}

			if (is_array($a_folders) && in_array($mailbox, $a_folders)) {
			$this->icache[$key][] = $mailbox;
			if (is_array($a_folders) && in_array($folder, $a_folders)) {
			$this->icache[$key][] = $folder;
			return true;
			}

			@@ -3406,23 +2991,22 @@
			/**
			* Returns the namespace where the folder is in
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			*
			* @return string One of 'personal', 'other' or 'shared'
			* @access public
			*/
			function mailbox_namespace($mailbox)
			public function folder_namespace($folder)
			{
			if ($mailbox == 'INBOX') {
			if ($folder == 'INBOX') {
			return 'personal';
			}

			foreach ($this->namespace as $type => $namespace) {
			if (is_array($namespace)) {
			foreach ($namespace as $ns) {
			if (strlen($ns[0])) {
			if ((strlen($ns[0])>1 && $mailbox == substr($ns[0], 0, -1))
			\|\| strpos($mailbox, $ns[0]) === 0
			if ($len = strlen($ns[0])) {
			if (($len > 1 && $folder == substr($ns[0], 0, -1))
			\|\| strpos($folder, $ns[0]) === 0
			) {
			return $type;
			}
			@@ -3441,62 +3025,66 @@
			* For input it adds the prefix. Use it before creating a folder in root
			* of the folders tree.
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			* @param string $mode Mode name (out/in)
			*
			* @return string Folder name
			*/
			function mod_mailbox($mailbox, $mode = 'out')
			public function mod_folder($folder, $mode = 'out')
			{
			if (!strlen($mailbox)) {
			return $mailbox;
			if (!strlen($folder)) {
			return $folder;
			}

			$prefix = $this->namespace['prefix']; // see set_env()
			$prefix_len = strlen($prefix);

			if (!$prefix_len) {
			return $mailbox;
			return $folder;
			}

			// remove prefix for output
			if ($mode == 'out') {
			if (substr($mailbox, 0, $prefix_len) === $prefix) {
			return substr($mailbox, $prefix_len);
			if (substr($folder, 0, $prefix_len) === $prefix) {
			return substr($folder, $prefix_len);
			}
			}
			// add prefix for input (e.g. folder creation)
			else {
			return $prefix . $mailbox;
			return $prefix . $folder;
			}

			return $mailbox;
			return $folder;
			}


			/**
			* Gets folder attributes from LIST response, e.g. \Noselect, \Noinferiors
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			* @param bool $force Set to True if attributes should be refreshed
			*
			* @return array Options list
			*/
			function mailbox_attributes($mailbox, $force=false)
			public function folder_attributes($folder, $force=false)
			{
			// get attributes directly from LIST command
			if (!empty($this->conn->data['LIST']) && is_array($this->conn->data['LIST'][$mailbox])) {
			$opts = $this->conn->data['LIST'][$mailbox];
			if (!empty($this->conn->data['LIST']) && is_array($this->conn->data['LIST'][$folder])) {
			$opts = $this->conn->data['LIST'][$folder];
			}
			// get cached folder attributes
			else if (!$force) {
			$opts = $this->get_cache('mailboxes.attributes');
			$opts = $opts[$mailbox];
			$opts = $opts[$folder];
			}

			if (!is_array($opts)) {
			$this->conn->listMailboxes('', $mailbox);
			$opts = $this->conn->data['LIST'][$mailbox];
			if (!$this->check_connection()) {
			return array();
			}

			$this->conn->listMailboxes('', $folder);
			$opts = $this->conn->data['LIST'][$folder];
			}

			return is_array($opts) ? $opts : array();
			@@ -3504,31 +3092,39 @@


			/**
			* Gets connection (and current mailbox) data: UIDVALIDITY, EXISTS, RECENT,
			* Gets connection (and current folder) data: UIDVALIDITY, EXISTS, RECENT,
			* PERMANENTFLAGS, UIDNEXT, UNSEEN
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			*
			* @return array Data
			*/
			function mailbox_data($mailbox)
			public function folder_data($folder)
			{
			if (!strlen($mailbox))
			$mailbox = $this->mailbox !== null ? $this->mailbox : 'INBOX';
			if (!strlen($folder)) {
			$folder = $this->folder !== null ? $this->folder : 'INBOX';
			}

			if ($this->conn->selected != $mailbox) {
			if ($this->conn->select($mailbox))
			$this->mailbox = $mailbox;
			else
			if ($this->conn->selected != $folder) {
			if (!$this->check_connection()) {
			return array();
			}

			if ($this->conn->select($folder)) {
			$this->folder = $folder;
			}
			else {
			return null;
			}
			}

			$data = $this->conn->data;

			// add (E)SEARCH result for ALL UNDELETED query
			if (!empty($this->icache['undeleted_idx']) && $this->icache['undeleted_idx'][0] == $mailbox) {
			$data['ALL_UNDELETED'] = $this->icache['undeleted_idx'][1];
			$data['COUNT_UNDELETED'] = $this->icache['undeleted_idx'][2];
			if (!empty($this->icache['undeleted_idx'])
			&& $this->icache['undeleted_idx']->get_parameters('MAILBOX') == $folder
			) {
			$data['UNDELETED'] = $this->icache['undeleted_idx'];
			}

			return $data;
			@@ -3538,13 +3134,13 @@
			/**
			* Returns extended information about the folder
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			*
			* @return array Data
			*/
			function mailbox_info($mailbox)
			public function folder_info($folder)
			{
			if ($this->icache['options'] && $this->icache['options']['name'] == $mailbox) {
			if ($this->icache['options'] && $this->icache['options']['name'] == $folder) {
			return $this->icache['options'];
			}

			@@ -3554,7 +3150,7 @@

			// check if the folder is a namespace prefix
			if (!empty($namespace)) {
			$mbox = $mailbox . $this->delimiter;
			$mbox = $folder . $this->delimiter;
			foreach ($namespace as $ns) {
			if (!empty($ns)) {
			foreach ($ns as $item) {
			@@ -3568,7 +3164,7 @@
			}
			// check if the folder is other user virtual-root
			if (!$options['is_root'] && !empty($namespace) && !empty($namespace['other'])) {
			$parts = explode($this->delimiter, $mailbox);
			$parts = explode($this->delimiter, $folder);
			if (count($parts) == 2) {
			$mbox = $parts[0] . $this->delimiter;
			foreach ($namespace['other'] as $item) {
			@@ -3580,11 +3176,11 @@
			}
			}

			$options['name'] = $mailbox;
			$options['attributes'] = $this->mailbox_attributes($mailbox, true);
			$options['namespace'] = $this->mailbox_namespace($mailbox);
			$options['rights'] = $acl && !$options['is_root'] ? (array)$this->my_rights($mailbox) : array();
			$options['special'] = in_array($mailbox, $this->default_folders);
			$options['name'] = $folder;
			$options['attributes'] = $this->folder_attributes($folder, true);
			$options['namespace'] = $this->folder_namespace($folder);
			$options['rights'] = $acl && !$options['is_root'] ? (array)$this->my_rights($folder) : array();
			$options['special'] = in_array($folder, $this->default_folders);

			// Set 'noselect' and 'norename' flags
			if (is_array($options['attributes'])) {
			@@ -3619,12 +3215,12 @@
			/**
			* Synchronizes messages cache.
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			*/
			public function mailbox_sync($mailbox)
			public function folder_sync($folder)
			{
			if ($mcache = $this->get_mcache_engine()) {
			$mcache->synchronize($mailbox);
			$mcache->synchronize($folder);
			}
			}

			@@ -3634,13 +3230,19 @@
			*
			* @return string Space-separated list of header names
			*/
			private function get_fetch_headers()
			protected function get_fetch_headers()
			{
			$headers = explode(' ', $this->fetch_add_headers);
			$headers = array_map('strtoupper', $headers);
			if (!empty($this->options['fetch_headers'])) {
			$headers = explode(' ', $this->options['fetch_headers']);
			$headers = array_map('strtoupper', $headers);
			}
			else {
			$headers = array();
			}

			if ($this->messages_caching \|\| $this->get_all_headers)
			if ($this->messages_caching \|\| $this->options['all_headers']) {
			$headers = array_merge($headers, $this->all_headers);
			}

			return implode(' ', array_unique($headers));
			}
			@@ -3651,128 +3253,149 @@
			* ----------------------------------------*/

			/**
			* Changes the ACL on the specified mailbox (SETACL)
			* Changes the ACL on the specified folder (SETACL)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param string $user User name
			* @param string $acl ACL string
			*
			* @return boolean True on success, False on failure
			*
			* @access public
			* @since 0.5-beta
			*/
			function set_acl($mailbox, $user, $acl)
			public function set_acl($folder, $user, $acl)
			{
			if ($this->get_capability('ACL'))
			return $this->conn->setACL($mailbox, $user, $acl);
			if (!$this->get_capability('ACL')) {
			return false;
			}

			return false;
			if (!$this->check_connection()) {
			return false;
			}

			return $this->conn->setACL($folder, $user, $acl);
			}


			/**
			* Removes any <identifier,rights> pair for the
			* specified user from the ACL for the specified
			* mailbox (DELETEACL)
			* folder (DELETEACL)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param string $user User name
			*
			* @return boolean True on success, False on failure
			*
			* @access public
			* @since 0.5-beta
			*/
			function delete_acl($mailbox, $user)
			public function delete_acl($folder, $user)
			{
			if ($this->get_capability('ACL'))
			return $this->conn->deleteACL($mailbox, $user);
			if (!$this->get_capability('ACL')) {
			return false;
			}

			return false;
			if (!$this->check_connection()) {
			return false;
			}

			return $this->conn->deleteACL($folder, $user);
			}


			/**
			* Returns the access control list for mailbox (GETACL)
			* Returns the access control list for folder (GETACL)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			*
			* @return array User-rights array on success, NULL on error
			* @access public
			* @since 0.5-beta
			*/
			function get_acl($mailbox)
			public function get_acl($folder)
			{
			if ($this->get_capability('ACL'))
			return $this->conn->getACL($mailbox);
			if (!$this->get_capability('ACL')) {
			return null;
			}

			return NULL;
			if (!$this->check_connection()) {
			return null;
			}

			return $this->conn->getACL($folder);
			}


			/**
			* Returns information about what rights can be granted to the
			* user (identifier) in the ACL for the mailbox (LISTRIGHTS)
			* user (identifier) in the ACL for the folder (LISTRIGHTS)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			* @param string $user User name
			*
			* @return array List of user rights
			* @access public
			* @since 0.5-beta
			*/
			function list_rights($mailbox, $user)
			public function list_rights($folder, $user)
			{
			if ($this->get_capability('ACL'))
			return $this->conn->listRights($mailbox, $user);
			if (!$this->get_capability('ACL')) {
			return null;
			}

			return NULL;
			if (!$this->check_connection()) {
			return null;
			}

			return $this->conn->listRights($folder, $user);
			}


			/**
			* Returns the set of rights that the current user has to
			* mailbox (MYRIGHTS)
			* folder (MYRIGHTS)
			*
			* @param string $mailbox Mailbox name
			* @param string $folder Folder name
			*
			* @return array MYRIGHTS response on success, NULL on error
			* @access public
			* @since 0.5-beta
			*/
			function my_rights($mailbox)
			public function my_rights($folder)
			{
			if ($this->get_capability('ACL'))
			return $this->conn->myRights($mailbox);
			if (!$this->get_capability('ACL')) {
			return null;
			}

			return NULL;
			if (!$this->check_connection()) {
			return null;
			}

			return $this->conn->myRights($folder);
			}


			/**
			* Sets IMAP metadata/annotations (SETMETADATA/SETANNOTATION)
			*
			* @param string $mailbox Mailbox name (empty for server metadata)
			* @param string $folder Folder name (empty for server metadata)
			* @param array $entries Entry-value array (use NULL value as NIL)
			*
			* @return boolean True on success, False on failure
			* @access public
			* @since 0.5-beta
			*/
			function set_metadata($mailbox, $entries)
			public function set_metadata($folder, $entries)
			{
			if (!$this->check_connection()) {
			return false;
			}

			if ($this->get_capability('METADATA') \|\|
			(!strlen($mailbox) && $this->get_capability('METADATA-SERVER'))
			(!strlen($folder) && $this->get_capability('METADATA-SERVER'))
			) {
			return $this->conn->setMetadata($mailbox, $entries);
			return $this->conn->setMetadata($folder, $entries);
			}
			else if ($this->get_capability('ANNOTATEMORE') \|\| $this->get_capability('ANNOTATEMORE2')) {
			foreach ((array)$entries as $entry => $value) {
			list($ent, $attr) = $this->md2annotate($entry);
			$entries[$entry] = array($ent, $attr, $value);
			}
			return $this->conn->setAnnotation($mailbox, $entries);
			return $this->conn->setAnnotation($folder, $entries);
			}

			return false;
			@@ -3782,27 +3405,29 @@
			/**
			* Unsets IMAP metadata/annotations (SETMETADATA/SETANNOTATION)
			*
			* @param string $mailbox Mailbox name (empty for server metadata)
			* @param string $folder Folder name (empty for server metadata)
			* @param array $entries Entry names array
			*
			* @return boolean True on success, False on failure
			*
			* @access public
			* @since 0.5-beta
			*/
			function delete_metadata($mailbox, $entries)
			public function delete_metadata($folder, $entries)
			{
			if (!$this->check_connection()) {
			return false;
			}

			if ($this->get_capability('METADATA') \|\|
			(!strlen($mailbox) && $this->get_capability('METADATA-SERVER'))
			(!strlen($folder) && $this->get_capability('METADATA-SERVER'))
			) {
			return $this->conn->deleteMetadata($mailbox, $entries);
			return $this->conn->deleteMetadata($folder, $entries);
			}
			else if ($this->get_capability('ANNOTATEMORE') \|\| $this->get_capability('ANNOTATEMORE2')) {
			foreach ((array)$entries as $idx => $entry) {
			list($ent, $attr) = $this->md2annotate($entry);
			$entries[$idx] = array($ent, $attr, NULL);
			}
			return $this->conn->setAnnotation($mailbox, $entries);
			return $this->conn->setAnnotation($folder, $entries);
			}

			return false;
			@@ -3812,21 +3437,23 @@
			/**
			* Returns IMAP metadata/annotations (GETMETADATA/GETANNOTATION)
			*
			* @param string $mailbox Mailbox name (empty for server metadata)
			* @param string $folder Folder name (empty for server metadata)
			* @param array $entries Entries
			* @param array $options Command options (with MAXSIZE and DEPTH keys)
			*
			* @return array Metadata entry-value hash array on success, NULL on error
			*
			* @access public
			* @since 0.5-beta
			*/
			function get_metadata($mailbox, $entries, $options=array())
			public function get_metadata($folder, $entries, $options=array())
			{
			if ($this->get_capability('METADATA') \|\|
			(!strlen($mailbox) && $this->get_capability('METADATA-SERVER'))
			if (!$this->check_connection()) {
			return null;
			}

			if ($this->get_capability('METADATA') \|\|
			(!strlen($folder) && $this->get_capability('METADATA-SERVER'))
			) {
			return $this->conn->getMetadata($mailbox, $entries, $options);
			return $this->conn->getMetadata($folder, $entries, $options);
			}
			else if ($this->get_capability('ANNOTATEMORE') \|\| $this->get_capability('ANNOTATEMORE2')) {
			$queries = array();
			@@ -3839,14 +3466,16 @@
			}

			// @TODO: Honor MAXSIZE and DEPTH options
			foreach ($queries as $attrib => $entry)
			if ($result = $this->conn->getAnnotation($mailbox, $entry, $attrib))
			foreach ($queries as $attrib => $entry) {
			if ($result = $this->conn->getAnnotation($folder, $entry, $attrib)) {
			$res = array_merge_recursive($res, $result);
			}
			}

			return $res;
			}

			return NULL;
			return null;
			}


			@@ -3858,7 +3487,7 @@
			*
			* @return array Entry-attribute list, NULL if not supported (?)
			*/
			private function md2annotate($entry)
			protected function md2annotate($entry)
			{
			if (substr($entry, 0, 7) == '/shared') {
			return array(substr($entry, 7), 'value.shared');
			@@ -3868,7 +3497,7 @@
			}

			// @TODO: log error
			return NULL;
			return null;
			}


			@@ -3879,17 +3508,17 @@
			/**
			* Enable or disable indexes caching
			*
			* @param string $type Cache type (@see rcmail::get_cache)
			* @access public
			* @param string $type Cache type (@see rcube::get_cache)
			*/
			function set_caching($type)
			public function set_caching($type)
			{
			if ($type) {
			$this->caching = $type;
			}
			else {
			if ($this->cache)
			if ($this->cache) {
			$this->cache->close();
			}
			$this->cache = null;
			$this->caching = false;
			}
			@@ -3898,11 +3527,12 @@
			/**
			* Getter for IMAP cache object
			*/
			private function get_cache_engine()
			protected function get_cache_engine()
			{
			if ($this->caching && !$this->cache) {
			$rcmail = rcmail::get_instance();
			$this->cache = $rcmail->get_cache('IMAP', $this->caching);
			$rcube = rcube::get_instance();
			$ttl = $rcube->config->get('message_cache_lifetime', '10d') - mktime();
			$this->cache = $rcube->get_cache('IMAP', $this->caching, $ttl);
			}

			return $this->cache;
			@@ -3912,10 +3542,10 @@
			* Returns cached value
			*
			* @param string $key Cache key
			*
			* @return mixed
			* @access public
			*/
			function get_cache($key)
			public function get_cache($key)
			{
			if ($cache = $this->get_cache_engine()) {
			return $cache->get($key);
			@@ -3927,9 +3557,8 @@
			*
			* @param string $key Cache key
			* @param mixed $data Data
			* @access public
			*/
			function update_cache($key, $data)
			public function update_cache($key, $data)
			{
			if ($cache = $this->get_cache_engine()) {
			$cache->set($key, $data);
			@@ -3942,12 +3571,26 @@
			* @param string $key Cache key name or pattern
			* @param boolean $prefix_mode Enable it to clear all keys starting
			* with prefix specified in $key
			* @access public
			*/
			function clear_cache($key=null, $prefix_mode=false)
			public function clear_cache($key = null, $prefix_mode = false)
			{
			if ($cache = $this->get_cache_engine()) {
			$cache->remove($key, $prefix_mode);
			}
			}

			/**
			* Delete outdated cache entries
			*/
			public function expunge_cache()
			{
			if ($this->mcache) {
			$ttl = rcube::get_instance()->config->get('message_cache_lifetime', '10d');
			$this->mcache->expunge($ttl);
			}

			if ($this->cache) {
			$this->cache->expunge();
			}
			}

			@@ -3961,266 +3604,54 @@
			*
			* @param boolean $set Flag
			*/
			function set_messages_caching($set)
			public function set_messages_caching($set)
			{
			if ($set) {
			$this->messages_caching = true;
			}
			else {
			if ($this->mcache)
			if ($this->mcache) {
			$this->mcache->close();
			}
			$this->mcache = null;
			$this->messages_caching = false;
			}
			}


			/**
			* Getter for messages cache object
			*/
			private function get_mcache_engine()
			protected function get_mcache_engine()
			{
			if ($this->messages_caching && !$this->mcache) {
			$rcmail = rcmail::get_instance();
			if ($dbh = $rcmail->get_dbh()) {
			$rcube = rcube::get_instance();
			if ($dbh = $rcube->get_dbh()) {
			$this->mcache = new rcube_imap_cache(
			$dbh, $this, $rcmail->user->ID, $this->skip_deleted);
			$dbh, $this, $rcube->get_user_id(), $this->options['skip_deleted']);
			}
			}

			return $this->mcache;
			}


			/**
			* Clears the messages cache.
			*
			* @param string $mailbox Folder name
			* @param string $folder Folder name
			* @param array $uids Optional message UIDs to remove from cache
			*/
			function clear_message_cache($mailbox = null, $uids = null)
			protected function clear_message_cache($folder = null, $uids = null)
			{
			if ($mcache = $this->get_mcache_engine()) {
			$mcache->clear($mailbox, $uids);
			$mcache->clear($folder, $uids);
			}
			}



			/* --------------------------------
			* encoding/decoding methods
			* --------------------------------*/

			/**
			* Split an address list into a structured array list
			*
			* @param string $input Input string
			* @param int $max List only this number of addresses
			* @param boolean $decode Decode address strings
			* @return array Indexed list of addresses
			*/
			function decode_address_list($input, $max=null, $decode=true)
			{
			$a = $this->_parse_address_list($input, $decode);
			$out = array();
			// Special chars as defined by RFC 822 need to in quoted string (or escaped).
			$special_chars = '[\<\>\\\.\[\]@,;:"]';

			if (!is_array($a))
			return $out;

			$c = count($a);
			$j = 0;

			foreach ($a as $val) {
			$j++;
			$address = trim($val['address']);
			$name = trim($val['name']);

			if ($name && $address && $name != $address)
			$string = sprintf('%s <%s>', preg_match("/$special_chars/", $name) ? '"'.addcslashes($name, '"').'"' : $name, $address);
			else if ($address)
			$string = $address;
			else if ($name)
			$string = $name;

			$out[$j] = array(
			'name' => $name,
			'mailto' => $address,
			'string' => $string
			);

			if ($max && $j==$max)
			break;
			}

			return $out;
			}


			/**
			* Decode a message header value
			*
			* @param string $input Header value
			* @param boolean $remove_quotas Remove quotes if necessary
			* @return string Decoded string
			*/
			function decode_header($input, $remove_quotes=false)
			{
			$str = rcube_imap::decode_mime_string((string)$input, $this->default_charset);
			if ($str[0] == '"' && $remove_quotes)
			$str = str_replace('"', '', $str);

			return $str;
			}


			/**
			* Decode a mime-encoded string to internal charset
			*
			* @param string $input Header value
			* @param string $fallback Fallback charset if none specified
			*
			* @return string Decoded string
			* @static
			*/
			public static function decode_mime_string($input, $fallback=null)
			{
			if (!empty($fallback)) {
			$default_charset = $fallback;
			}
			else {
			$default_charset = rcmail::get_instance()->config->get('default_charset', 'ISO-8859-1');
			}

			// rfc: all line breaks or other characters not found
			// in the Base64 Alphabet must be ignored by decoding software
			// delete all blanks between MIME-lines, differently we can
			// receive unnecessary blanks and broken utf-8 symbols
			$input = preg_replace("/\?=\s+=\?/", '?==?', $input);

			// encoded-word regexp
			$re = '/=\?([^?]+)\?([BbQq])\?([^?\n]*)\?=/';

			// Find all RFC2047's encoded words
			if (preg_match_all($re, $input, $matches, PREG_OFFSET_CAPTURE \| PREG_SET_ORDER)) {
			// Initialize variables
			$tmp = array();
			$out = '';
			$start = 0;

			foreach ($matches as $idx => $m) {
			$pos = $m[0][1];
			$charset = $m[1][0];
			$encoding = $m[2][0];
			$text = $m[3][0];
			$length = strlen($m[0][0]);

			// Append everything that is before the text to be decoded
			if ($start != $pos) {
			$substr = substr($input, $start, $pos-$start);
			$out .= rcube_charset_convert($substr, $default_charset);
			$start = $pos;
			}
			$start += $length;

			// Per RFC2047, each string part "MUST represent an integral number
			// of characters . A multi-octet character may not be split across
			// adjacent encoded-words." However, some mailers break this, so we
			// try to handle characters spanned across parts anyway by iterating
			// through and aggregating sequential encoded parts with the same
			// character set and encoding, then perform the decoding on the
			// aggregation as a whole.

			$tmp[] = $text;
			if ($next_match = $matches[$idx+1]) {
			if ($next_match[0][1] == $start
			&& $next_match[1][0] == $charset
			&& $next_match[2][0] == $encoding
			) {
			continue;
			}
			}

			$count = count($tmp);
			$text = '';

			// Decode and join encoded-word's chunks
			if ($encoding == 'B' \|\| $encoding == 'b') {
			// base64 must be decoded a segment at a time
			for ($i=0; $i<$count; $i++)
			$text .= base64_decode($tmp[$i]);
			}
			else { //if ($encoding == 'Q' \|\| $encoding == 'q') {
			// quoted printable can be combined and processed at once
			for ($i=0; $i<$count; $i++)
			$text .= $tmp[$i];

			$text = str_replace('_', ' ', $text);
			$text = quoted_printable_decode($text);
			}

			$out .= rcube_charset_convert($text, $charset);
			$tmp = array();
			}

			// add the last part of the input string
			if ($start != strlen($input)) {
			$out .= rcube_charset_convert(substr($input, $start), $default_charset);
			}

			// return the results
			return $out;
			}

			// no encoding information, use fallback
			return rcube_charset_convert($input, $default_charset);
			}


			/**
			* Decode a mime part
			*
			* @param string $input Input string
			* @param string $encoding Part encoding
			* @return string Decoded string
			*/
			function mime_decode($input, $encoding='7bit')
			{
			switch (strtolower($encoding)) {
			case 'quoted-printable':
			return quoted_printable_decode($input);
			case 'base64':
			return base64_decode($input);
			case 'x-uuencode':
			case 'x-uue':
			case 'uue':
			case 'uuencode':
			return convert_uudecode($input);
			case '7bit':
			default:
			return $input;
			}
			}


			/**
			* Convert body charset to RCMAIL_CHARSET according to the ctype_parameters
			*
			* @param string $body Part body to decode
			* @param string $ctype_param Charset to convert from
			* @return string Content converted to internal charset
			*/
			function charset_decode($body, $ctype_param)
			{
			if (is_array($ctype_param) && !empty($ctype_param['charset']))
			return rcube_charset_convert($body, $ctype_param['charset']);

			// defaults to what is specified in the class header
			return rcube_charset_convert($body, $this->default_charset);
			}


			/* --------------------------------
			* private methods
			* protected methods
			* --------------------------------*/

			/**
			@@ -4228,24 +3659,24 @@
			*
			* @param string $sort_field Sort column
			* @param string $sort_order Sort order
			* @access private
			*/
			private function _set_sort_order($sort_field, $sort_order)
			protected function set_sort_order($sort_field, $sort_order)
			{
			if ($sort_field != null)
			if ($sort_field != null) {
			$this->sort_field = asciiwords($sort_field);
			if ($sort_order != null)
			}
			if ($sort_order != null) {
			$this->sort_order = strtoupper($sort_order) == 'DESC' ? 'DESC' : 'ASC';
			}
			}


			/**
			* Sort mailboxes first by default folders and then in alphabethical order
			* Sort folders first by default folders and then in alphabethical order
			*
			* @param array $a_folders Mailboxes list
			* @access private
			* @param array $a_folders Folders list
			*/
			private function _sort_mailbox_list($a_folders)
			protected function sort_folder_list($a_folders)
			{
			$a_out = $a_defaults = $folders = array();

			@@ -4253,13 +3684,16 @@

			// find default folders and skip folders starting with '.'
			foreach ($a_folders as $i => $folder) {
			if ($folder[0] == '.')
			if ($folder[0] == '.') {
			continue;
			}

			if (($p = array_search($folder, $this->default_folders)) !== false && !$a_defaults[$p])
			if (($p = array_search($folder, $this->default_folders)) !== false && !$a_defaults[$p]) {
			$a_defaults[$p] = $folder;
			else
			$folders[$folder] = rcube_charset_convert($folder, 'UTF7-IMAP');
			}
			else {
			$folders[$folder] = rcube_charset::convert($folder, 'UTF7-IMAP');
			}
			}

			// sort folders and place defaults on the top
			@@ -4275,7 +3709,7 @@
			// set the type of folder name variable (#1485527)
			$a_out[] = (string) $folder;
			unset($folders[$key]);
			$this->_rsort($folder, $delimiter, $folders, $a_out);
			$this->rsort($folder, $delimiter, $folders, $a_out);
			}

			return $a_out;
			@@ -4283,16 +3717,16 @@


			/**
			* @access private
			* Recursive method for sorting folders
			*/
			private function _rsort($folder, $delimiter, &$list, &$out)
			protected function rsort($folder, $delimiter, &$list, &$out)
			{
			while (list($key, $name) = each($list)) {
			if (strpos($name, $folder.$delimiter) === 0) {
			// set the type of folder name variable (#1485527)
			$out[] = (string) $name;
			unset($list[$key]);
			$this->_rsort($name, $delimiter, $list, $out);
			$this->rsort($name, $delimiter, $list, $out);
			}
			}
			reset($list);
			@@ -4300,86 +3734,60 @@


			/**
			* Finds message sequence ID for specified UID
			*
			* @param int $uid Message UID
			* @param string $mailbox Mailbox name
			* @param bool $force True to skip cache
			*
			* @return int Message (sequence) ID
			*/
			function uid2id($uid, $mailbox = null, $force = false)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			}

			if (!empty($this->uid_id_map[$mailbox][$uid])) {
			return $this->uid_id_map[$mailbox][$uid];
			}

			if (!$force && ($mcache = $this->get_mcache_engine()))
			$id = $mcache->uid2id($mailbox, $uid);

			if (empty($id))
			$id = $this->conn->UID2ID($mailbox, $uid);

			$this->uid_id_map[$mailbox][$uid] = $id;

			return $id;
			}


			/**
			* Find UID of the specified message sequence ID
			*
			* @param int $id Message (sequence) ID
			* @param string $mailbox Mailbox name
			* @param bool $force True to skip cache
			* @param string $folder Folder name
			*
			* @return int Message UID
			*/
			function id2uid($id, $mailbox = null, $force = false)
			public function id2uid($id, $folder = null)
			{
			if (!strlen($mailbox)) {
			$mailbox = $this->mailbox;
			if (!strlen($folder)) {
			$folder = $this->folder;
			}

			if ($uid = array_search($id, (array)$this->uid_id_map[$mailbox])) {
			if ($uid = array_search($id, (array)$this->uid_id_map[$folder])) {
			return $uid;
			}

			if (!$force && ($mcache = $this->get_mcache_engine()))
			$uid = $mcache->id2uid($mailbox, $id);
			if (!$this->check_connection()) {
			return null;
			}

			if (empty($uid))
			$uid = $this->conn->ID2UID($mailbox, $id);
			$uid = $this->conn->ID2UID($folder, $id);

			$this->uid_id_map[$mailbox][$uid] = $id;
			$this->uid_id_map[$folder][$uid] = $id;

			return $uid;
			}


			/**
			* Subscribe/unsubscribe a list of mailboxes and update local cache
			* @access private
			* Subscribe/unsubscribe a list of folders and update local cache
			*/
			private function _change_subscription($a_mboxes, $mode)
			protected function change_subscription($folders, $mode)
			{
			$updated = false;

			if (is_array($a_mboxes))
			foreach ($a_mboxes as $i => $mailbox) {
			$a_mboxes[$i] = $mailbox;

			if ($mode == 'subscribe')
			$updated = $this->conn->subscribe($mailbox);
			else if ($mode == 'unsubscribe')
			$updated = $this->conn->unsubscribe($mailbox);
			if (!empty($folders)) {
			if (!$this->check_connection()) {
			return false;
			}

			// clear cached mailbox list(s)
			foreach ((array)$folders as $i => $folder) {
			$folders[$i] = $folder;

			if ($mode == 'subscribe') {
			$updated = $this->conn->subscribe($folder);
			}
			else if ($mode == 'unsubscribe') {
			$updated = $this->conn->unsubscribe($folder);
			}
			}
			}

			// clear cached folders list(s)
			if ($updated) {
			$this->clear_cache('mailboxes', true);
			}
			@@ -4389,203 +3797,52 @@


			/**
			* Increde/decrese messagecount for a specific mailbox
			* @access private
			* Increde/decrese messagecount for a specific folder
			*/
			private function _set_messagecount($mailbox, $mode, $increment)
			protected function set_messagecount($folder, $mode, $increment)
			{
			$mode = strtoupper($mode);
			$a_mailbox_cache = $this->get_cache('messagecount');

			if (!is_array($a_mailbox_cache[$mailbox]) \|\| !isset($a_mailbox_cache[$mailbox][$mode]) \|\| !is_numeric($increment))
			if (!is_numeric($increment)) {
			return false;
			}

			$mode = strtoupper($mode);
			$a_folder_cache = $this->get_cache('messagecount');

			if (!is_array($a_folder_cache[$folder]) \|\| !isset($a_folder_cache[$folder][$mode])) {
			return false;
			}

			// add incremental value to messagecount
			$a_mailbox_cache[$mailbox][$mode] += $increment;
			$a_folder_cache[$folder][$mode] += $increment;

			// there's something wrong, delete from cache
			if ($a_mailbox_cache[$mailbox][$mode] < 0)
			unset($a_mailbox_cache[$mailbox][$mode]);
			if ($a_folder_cache[$folder][$mode] < 0) {
			unset($a_folder_cache[$folder][$mode]);
			}

			// write back to cache
			$this->update_cache('messagecount', $a_mailbox_cache);
			$this->update_cache('messagecount', $a_folder_cache);

			return true;
			}


			/**
			* Remove messagecount of a specific mailbox from cache
			* @access private
			* Remove messagecount of a specific folder from cache
			*/
			private function _clear_messagecount($mailbox, $mode=null)
			protected function clear_messagecount($folder, $mode=null)
			{
			$a_mailbox_cache = $this->get_cache('messagecount');
			$a_folder_cache = $this->get_cache('messagecount');

			if (is_array($a_mailbox_cache[$mailbox])) {
			if (is_array($a_folder_cache[$folder])) {
			if ($mode) {
			unset($a_mailbox_cache[$mailbox][$mode]);
			unset($a_folder_cache[$folder][$mode]);
			}
			else {
			unset($a_mailbox_cache[$mailbox]);
			unset($a_folder_cache[$folder]);
			}
			$this->update_cache('messagecount', $a_mailbox_cache);
			$this->update_cache('messagecount', $a_folder_cache);
			}
			}


			/**
			* Split RFC822 header string into an associative array
			* @access private
			*/
			private function _parse_headers($headers)
			{
			$a_headers = array();
			$headers = preg_replace('/\r?\n(\t\| )+/', ' ', $headers);
			$lines = explode("\n", $headers);
			$c = count($lines);

			for ($i=0; $i<$c; $i++) {
			if ($p = strpos($lines[$i], ': ')) {
			$field = strtolower(substr($lines[$i], 0, $p));
			$value = trim(substr($lines[$i], $p+1));
			if (!empty($value))
			$a_headers[$field] = $value;
			}
			}

			return $a_headers;
			}


			/**
			* @access private
			*/
			private function _parse_address_list($str, $decode=true)
			{
			// remove any newlines and carriage returns before
			$str = preg_replace('/\r?\n(\s\|\t)?/', ' ', $str);

			// extract list items, remove comments
			$str = self::explode_header_string(',;', $str, true);
			$result = array();

			// simplified regexp, supporting quoted local part
			$email_rx = '(\S+\|("\s(?:[^"\f\n\r\t\v\b\s]+\s)+"))@\S+';

			foreach ($str as $key => $val) {
			$name = '';
			$address = '';
			$val = trim($val);

			if (preg_match('/(.*)<('.$email_rx.')>$/', $val, $m)) {
			$address = $m[2];
			$name = trim($m[1]);
			}
			else if (preg_match('/^('.$email_rx.')$/', $val, $m)) {
			$address = $m[1];
			$name = '';
			}
			else {
			$name = $val;
			}

			// dequote and/or decode name
			if ($name) {
			if ($name[0] == '"' && $name[strlen($name)-1] == '"') {
			$name = substr($name, 1, -1);
			$name = stripslashes($name);
			}
			if ($decode) {
			$name = $this->decode_header($name);
			}
			}

			if (!$address && $name) {
			$address = $name;
			}

			if ($address) {
			$result[$key] = array('name' => $name, 'address' => $address);
			}
			}

			return $result;
			}


			/**
			* Explodes header (e.g. address-list) string into array of strings
			* using specified separator characters with proper handling
			* of quoted-strings and comments (RFC2822)
			*
			* @param string $separator String containing separator characters
			* @param string $str Header string
			* @param bool $remove_comments Enable to remove comments
			*
			* @return array Header items
			*/
			static function explode_header_string($separator, $str, $remove_comments=false)
			{
			$length = strlen($str);
			$result = array();
			$quoted = false;
			$comment = 0;
			$out = '';

			for ($i=0; $i<$length; $i++) {
			// we're inside a quoted string
			if ($quoted) {
			if ($str[$i] == '"') {
			$quoted = false;
			}
			else if ($str[$i] == '\\') {
			if ($comment <= 0) {
			$out .= '\\';
			}
			$i++;
			}
			}
			// we're inside a comment string
			else if ($comment > 0) {
			if ($str[$i] == ')') {
			$comment--;
			}
			else if ($str[$i] == '(') {
			$comment++;
			}
			else if ($str[$i] == '\\') {
			$i++;
			}
			continue;
			}
			// separator, add to result array
			else if (strpos($separator, $str[$i]) !== false) {
			if ($out) {
			$result[] = $out;
			}
			$out = '';
			continue;
			}
			// start of quoted string
			else if ($str[$i] == '"') {
			$quoted = true;
			}
			// start of comment
			else if ($remove_comments && $str[$i] == '(') {
			$comment++;
			}

			if ($comment <= 0) {
			$out .= $str[$i];
			}
			}

			if ($out && $comment <= 0) {
			$result[] = $out;
			}

			return $result;
			}


			@@ -4595,116 +3852,142 @@
			*/
			public function debug_handler(&$imap, $message)
			{
			write_log('imap', $message);
			rcube::write_log('imap', $message);
			}

			} // end class rcube_imap


			/**
			* Class representing a message part
			*
			* @package Mail
			*/
			class rcube_message_part
			{
			var $mime_id = '';
			var $ctype_primary = 'text';
			var $ctype_secondary = 'plain';
			var $mimetype = 'text/plain';
			var $disposition = '';
			var $filename = '';
			var $encoding = '8bit';
			var $charset = '';
			var $size = 0;
			var $headers = array();
			var $d_parameters = array();
			var $ctype_parameters = array();

			function __clone()
			{
			if (isset($this->parts))
			foreach ($this->parts as $idx => $part)
			if (is_object($part))
			$this->parts[$idx] = clone $part;
			}
			}


			/**
			* Class for sorting an array of rcube_mail_header objects in a predetermined order.
			*
			* @package Mail
			* @author Eric Stadtherr
			*/
			class rcube_header_sorter
			{
			private $seqs = array();
			private $uids = array();


			/**
			* Set the predetermined sort order.
			*
			* @param array $index Numerically indexed array of IMAP ID or UIDs
			* @param bool $is_uid Set to true if $index contains UIDs
			* Deprecated methods (to be removed)
			*/
			function set_index($index, $is_uid = false)
			{
			$index = array_flip($index);

			if ($is_uid)
			$this->uids = $index;
			else
			$this->seqs = $index;
			public function decode_address_list($input, $max = null, $decode = true, $fallback = null)
			{
			return rcube_mime::decode_address_list($input, $max, $decode, $fallback);
			}

			/**
			* Sort the array of header objects
			*
			* @param array $headers Array of rcube_mail_header objects indexed by UID
			*/
			function sort_headers(&$headers)
			public function decode_header($input, $fallback = null)
			{
			if (!empty($this->uids))
			uksort($headers, array($this, "compare_uids"));
			else
			uasort($headers, array($this, "compare_seqnums"));
			return rcube_mime::decode_mime_string((string)$input, $fallback);
			}

			/**
			* Sort method called by uasort()
			*
			* @param rcube_mail_header $a
			* @param rcube_mail_header $b
			*/
			function compare_seqnums($a, $b)
			public static function decode_mime_string($input, $fallback = null)
			{
			// First get the sequence number from the header object (the 'id' field).
			$seqa = $a->id;
			$seqb = $b->id;

			// then find each sequence number in my ordered list
			$posa = isset($this->seqs[$seqa]) ? intval($this->seqs[$seqa]) : -1;
			$posb = isset($this->seqs[$seqb]) ? intval($this->seqs[$seqb]) : -1;

			// return the relative position as the comparison value
			return $posa - $posb;
			return rcube_mime::decode_mime_string($input, $fallback);
			}

			/**
			* Sort method called by uksort()
			*
			* @param int $a Array key (UID)
			* @param int $b Array key (UID)
			*/
			function compare_uids($a, $b)
			public function mime_decode($input, $encoding = '7bit')
			{
			// then find each sequence number in my ordered list
			$posa = isset($this->uids[$a]) ? intval($this->uids[$a]) : -1;
			$posb = isset($this->uids[$b]) ? intval($this->uids[$b]) : -1;

			// return the relative position as the comparison value
			return $posa - $posb;
			return rcube_mime::decode($input, $encoding);
			}

			public static function explode_header_string($separator, $str, $remove_comments = false)
			{
			return rcube_mime::explode_header_string($separator, $str, $remove_comments);
			}

			public function select_mailbox($mailbox)
			{
			// do nothing
			}

			public function set_mailbox($folder)
			{
			$this->set_folder($folder);
			}

			public function get_mailbox_name()
			{
			return $this->get_folder();
			}

			public function list_headers($folder='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
			{
			return $this->list_messages($folder, $page, $sort_field, $sort_order, $slice);
			}

			public function mailbox_status($folder = null)
			{
			return $this->folder_status($folder);
			}

			public function message_index($folder = '', $sort_field = NULL, $sort_order = NULL)
			{
			return $this->index($folder, $sort_field, $sort_order);
			}

			public function message_index_direct($folder, $sort_field = null, $sort_order = null, $skip_cache = true)
			{
			return $this->index_direct($folder, $sort_field, $sort_order, $skip_cache);
			}

			public function list_mailboxes($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			{
			return $this->list_folders_subscribed($root, $name, $filter, $rights, $skip_sort);
			}

			public function list_unsubscribed($root='', $name='*', $filter=null, $rights=null, $skip_sort=false)
			{
			return $this->list_folders($root, $name, $filter, $rights, $skip_sort);
			}

			public function get_mailbox_size($folder)
			{
			return $this->folder_size($folder);
			}

			public function create_mailbox($folder, $subscribe=false)
			{
			return $this->create_folder($folder, $subscribe);
			}

			public function rename_mailbox($folder, $new_name)
			{
			return $this->rename_folder($folder, $new_name);
			}

			function delete_mailbox($folder)
			{
			return $this->delete_folder($folder);
			}

			public function mailbox_exists($folder, $subscription=false)
			{
			return $this->folder_exists($folder, $subscription);
			}

			public function mailbox_namespace($folder)
			{
			return $this->folder_namespace($folder);
			}

			public function mod_mailbox($folder, $mode = 'out')
			{
			return $this->mod_folder($folder, $mode);
			}

			public function mailbox_attributes($folder, $force=false)
			{
			return $this->folder_attributes($folder, $force);
			}

			public function mailbox_data($folder)
			{
			return $this->folder_data($folder);
			}

			public function mailbox_info($folder)
			{
			return $this->folder_info($folder);
			}

			public function mailbox_sync($folder)
			{
			return $this->folder_sync($folder);
			}

			public function expunge($folder='', $clear_cache=true)
			{
			return $this->expunge_folder($folder, $clear_cache);
			}

			}