roundcubemail/program/lib/imap.inc

<?php
/////////////////////////////////////////////////////////
//	
//	Iloha IMAP Library (IIL)
//
//	(C)Copyright 2002 Ryo Chijiiwa <Ryo@IlohaMail.org>
//
//	This file is part of IlohaMail. IlohaMail is free software released 
//	under the GPL license.  See enclosed file COPYING for details, or 
//	see http://www.fsf.org/copyleft/gpl.html
//
/////////////////////////////////////////////////////////

/********************************************************

	FILE: include/imap.inc
	PURPOSE:
		Provide alternative IMAP library that doesn't rely on the standard 
		C-Client based version.  This allows IlohaMail to function regardless
		of whether or not the PHP build it's running on has IMAP functionality
		built-in.
	USEAGE:
		Function containing "_C_" in name require connection handler to be
		passed as one of the parameters.  To obtain connection handler, use
		iil_Connect()
	VERSION:
		IlohaMail-0.9-20050415
	CHANGES:
		File altered by Thomas Bruederli <roundcube@gmail.com>
		to fit enhanced equirements by the RoundCube Webmail:
		- Added list of server capabilites and check these before invoking commands
		- Added junk flag to iilBasicHeader
		- Enhanced error reporting on fsockopen()
		- Additional parameter for SORT command
		- Removed Call-time pass-by-reference because deprecated
		- Parse charset from content-type in iil_C_FetchHeaders()
		- Enhanced heaer sorting
		- Pass message as reference in iil_C_Append (to save memory)
		- Added BCC and REFERENCE to the list of headers to fetch in iil_C_FetchHeaders()
		- Leave messageID unchanged in iil_C_FetchHeaders()
		- Avoid stripslahes in iil_Connect()
		- Escape quotes and backslashes in iil_C_Login()
		- Added patch to iil_SortHeaders() by Richard Green
		- Removed <br> from error messages (better for logging)
		- Added patch to iil_C_Sort() enabling UID SORT commands
		- Added function iil_C_ID2UID()
		- Casting date parts in iil_StrToTime() to avoid mktime() warnings
		- Also acceppt LIST responses in iil_C_ListSubscribed()
		- Sanity check of $message_set in iil_C_FetchHeaders(), iil_C_FetchHeaderIndex(), iil_C_FetchThreadHeaders()
		- Implemented UID FETCH in iil_C_FetchHeaders()
		- Abort do-loop on socket errors (fgets returns false)
		- $ICL_SSL is not boolean anymore but contains the connection schema (ssl or tls)
		- Removed some debuggers (echo ...)
		File altered by Aleksander Machniak <alec@alec.pl>
		- trim(chop()) replaced by trim()
		- added iil_Escape()/iil_UnEscape() with support for " and \ in folder names
		- support \ character in username in iil_C_Login()
		- fixed iil_MultLine(): use iil_ReadBytes() instead of iil_ReadLine()
		- fixed iil_C_FetchStructureString() to handle many literal strings in response
		- removed hardcoded data size in iil_ReadLine() 
		- added iil_PutLine() wrapper for fputs()
		- code cleanup and identation fixes
		- removed flush() calls in iil_C_HandlePartBody() to prevent from memory leak (#1485187)
		- don't return "??" from iil_C_GetQuota()
		- RFC3501 [7.1] don't call CAPABILITY if was returned in server 
		  optional resposne in iil_Connect(), added iil_C_GetCapability()
		- remove 'undisclosed-recipients' string from 'To' header
		- iil_C_HandlePartBody(): added 6th argument and fixed endless loop
		- added iil_PutLineC() 
		- fixed iil_C_Sort() to support very long and/or divided responses
		- added BYE/BAD response simple support for endless loop prevention
		- added 3rd argument in iil_StartsWith* functions
		- fix iil_C_FetchPartHeader() in some cases by use of iil_C_HandlePartBody()
		- allow iil_C_HandlePartBody() to fetch whole message
		- optimize iil_C_FetchHeaders() to use only one FETCH command
		- added 4th argument to iil_Connect()
		- allow setting rootdir and delimiter before connect
		- support multiquota result
		- include BODYSTRUCTURE in iil_C_FetchHeaders()
		- added iil_C_FetchMIMEHeaders() function
		- added \* flag support 

********************************************************/

/**
 * @todo Possibly clean up more CS.
 * @todo Try to replace most double-quotes with single-quotes.
 * @todo Split this file into smaller files.
 * @todo Refactor code.
 * @todo Replace echo-debugging (make it adhere to config setting and log)
 */

// changed path to work within roundcube webmail
include_once 'lib/icl_commons.inc';


if (!isset($IMAP_USE_HEADER_DATE) || !$IMAP_USE_HEADER_DATE) {
    $IMAP_USE_INTERNAL_DATE = true;
}

/**
 * @todo Maybe use date() to generate this.
 */
$GLOBALS['IMAP_MONTHS'] = array("Jan" => 1, "Feb" => 2, "Mar" => 3, "Apr" => 4,
    "May" => 5, "Jun" => 6, "Jul" => 7, "Aug" => 8, "Sep" => 9, "Oct" => 10,
    "Nov" => 11, "Dec" => 12);

$GLOBALS['IMAP_SERVER_TZ'] = date('Z');

$GLOBALS['IMAP_FLAGS'] = array(
    'SEEN'     => '\\Seen',
    'DELETED'  => '\\Deleted',
    'RECENT'   => '\\Recent',
    'ANSWERED' => '\\Answered',
    'DRAFT'    => '\\Draft',
    'FLAGGED'  => '\\Flagged',
    'FORWARDED' => '$Forwarded',
    'MDNSENT'  => '$MDNSent',
    '*'        => '\\*',
);

$iil_error;
$iil_errornum;
$iil_selected;

/**
 * @todo Change class vars to public/private
 */
class iilConnection
{
	var $fp;
	var $error;
	var $errorNum;
	var $selected;
	var $message;
	var $host;
	var $cache;
	var $uid_cache;
	var $do_cache;
	var $exists;
	var $recent;
	var $rootdir;
	var $delimiter;
	var $capability = array();
	var $permanentflags = array();
	var $capability_readed = false;
}

/**
 * @todo Change class vars to public/private
 */
class iilBasicHeader
{
	var $id;
	var $uid;
	var $subject;
	var $from;
	var $to;
	var $cc;
	var $replyto;
	var $in_reply_to;
	var $date;
	var $messageID;
	var $size;
	var $encoding;
	var $charset;
	var $ctype;
	var $flags;
	var $timestamp;
	var $f;
	var $body_structure;
	var $internaldate;
	var $references;
	var $priority;
	var $mdn_to;
	var $mdn_sent = false;
	var $is_draft = false;
	var $seen = false;
	var $deleted = false;
	var $recent = false;
	var $answered = false;
	var $forwarded = false;
	var $junk = false;
	var $flagged = false;
}

/**
 * @todo Change class vars to public/private
 */
class iilThreadHeader
{
	var $id;
	var $sbj;
	var $irt;
	var $mid;
}

function iil_xor($string, $string2) {
	$result = '';
	$size = strlen($string);
	for ($i=0; $i<$size; $i++) {
    		$result .= chr(ord($string[$i]) ^ ord($string2[$i]));
	}
	return $result;
}

function iil_PutLine($fp, $string, $endln=true) {
//      console('C: '. rtrim($string));
        return fputs($fp, $string . ($endln ? "\r\n" : ''));
}

// iil_PutLine replacement with Command Continuation Requests (RFC3501 7.5) support
function iil_PutLineC($fp, $string, $endln=true) {
	if ($endln)
		$string .= "\r\n";

	$res = 0;
	if ($parts = preg_split('/(\{[0-9]+\}\r\n)/m', $string, -1, PREG_SPLIT_DELIM_CAPTURE)) {
		for($i=0, $cnt=count($parts); $i<$cnt; $i++) {
			if(preg_match('/^\{[0-9]+\}\r\n$/', $parts[$i+1])) {
				$res += iil_PutLine($fp, $parts[$i].$parts[$i+1], false);
				$line = iil_ReadLine($fp, 1000);
				// handle error in command
				if ($line[0] != '+')
					return false;
				$i++;
			}
			else
				$res += iil_PutLine($fp, $parts[$i], false);
		}
	}
	return $res;
}

function iil_ReadLine($fp, $size) {
	$line = '';

	if (!$fp) {
    		return $line;
	}
    
	if (!$size) {
		$size = 1024;
	}
    
	do {
    		$buffer = fgets($fp, $size);
    		if ($buffer === false) {
        		break;
    		}
//		console('S: '. chop($buffer));
    		$line .= $buffer;
	} while ($buffer[strlen($buffer)-1] != "\n");
	
	return $line;
}

function iil_MultLine($fp, $line) {
	$line = chop($line);
	if (ereg('\{[0-9]+\}$', $line)) {
		$out = '';
        
		preg_match_all('/(.*)\{([0-9]+)\}$/', $line, $a);
		$bytes = $a[2][0];
		while (strlen($out) < $bytes) {
			$line = iil_ReadBytes($fp, $bytes); 
			$out .= $line;
		}
		$line = $a[1][0] . "\"$out\"";
//		console('[...] '. $out);
	}
	return $line;
}

function iil_ReadBytes($fp, $bytes) {
	$data = '';
	$len  = 0;
	do {
    		$data .= fread($fp, $bytes-$len);
		if ($len == strlen($data)) {
    		        break; //nothing was read -> exit to avoid apache lockups
    		}
    		$len = strlen($data);
	} while ($len < $bytes);
	
	return $data;
}

function iil_ReadReply($fp) {
	do {
		$line = trim(iil_ReadLine($fp, 1024));
	} while ($line[0] == '*');
	
	return $line;
}

function iil_ParseResult($string) {
	$a = explode(' ', $string);
	if (count($a) > 2) {
		if (strcasecmp($a[1], 'OK') == 0) {
			return 0;
		} else if (strcasecmp($a[1], 'NO') == 0) {
			return -1;
		} else if (strcasecmp($a[1], 'BAD') == 0) {
			return -2;
		} else if (strcasecmp($a[1], 'BYE') == 0) {
			return -3;
    		}
	}
	return -4;
}

// check if $string starts with $match (or * BYE/BAD)
function iil_StartsWith($string, $match, $error=false) {
	$len = strlen($match);
	if ($len == 0) {
		return false;
	}
	if (strncmp($string, $match, $len) == 0) {
		return true;
	}
	if ($error && preg_match('/^\* (BYE|BAD) /', $string)) {
		return true;
	}
	return false;
}

function iil_StartsWithI($string, $match, $bye=false) {
	$len = strlen($match);
	if ($len == 0) {
		return false;
	}
	if (strncasecmp($string, $match, $len) == 0) {
		return true;
	}
	if ($bye && strncmp($string, '* BYE ', 6) == 0) {
		return true;

	}
	return false;
}

function iil_Escape($string)
{
	return strtr($string, array('"'=>'\\"', '\\' => '\\\\')); 
}

function iil_UnEscape($string)
{
	return strtr($string, array('\\"'=>'"', '\\\\' => '\\')); 
}

function iil_C_GetCapability(&$conn, $name)
{
	if (in_array($name, $conn->capability)) {
		return true;
	}
	else if ($conn->capability_readed) {
		return false;
	}

	// get capabilities (only once) because initial 
	// optional CAPABILITY response may differ
	$conn->capability = array();

	iil_PutLine($conn->fp, "cp01 CAPABILITY");
	do {
		$line = trim(iil_ReadLine($conn->fp, 1024));
		$a = explode(' ', $line);
		if ($line[0] == '*') {
			while (list($k, $w) = each($a)) {
				if ($w != '*' && $w != 'CAPABILITY')
    					$conn->capability[] = strtoupper($w);
			}
		}
	} while ($a[0] != 'cp01');
	
	$conn->capability_readed = true;

	if (in_array($name, $conn->capability)) {
		return true;
	}

	return false;
}

function iil_C_ClearCapability(&$conn)
{
	$conn->capability = array();
	$conn->capability_readed = false;
}

function iil_C_Authenticate(&$conn, $user, $pass, $encChallenge) {
    
    $ipad = '';
    $opad = '';
    
    // initialize ipad, opad
    for ($i=0;$i<64;$i++) {
        $ipad .= chr(0x36);
        $opad .= chr(0x5C);
    }

    // pad $pass so it's 64 bytes
    $padLen = 64 - strlen($pass);
    for ($i=0;$i<$padLen;$i++) {
        $pass .= chr(0);
    }
    
    // generate hash
    $hash  = md5(iil_xor($pass,$opad) . pack("H*", md5(iil_xor($pass, $ipad) . base64_decode($encChallenge))));
    
    // generate reply
    $reply = base64_encode($user . ' ' . $hash);
    
    // send result, get reply
    iil_PutLine($conn->fp, $reply);
    $line = iil_ReadLine($conn->fp, 1024);
    
    // process result
    $result = iil_ParseResult($line);
    if ($result == 0) {
        $conn->error    .= '';
        $conn->errorNum  = 0;
        return $conn->fp;
    }

    if ($result == -3) fclose($conn->fp); // BYE response

    $conn->error    .= 'Authentication for ' . $user . ' failed (AUTH): "';
    $conn->error    .= htmlspecialchars($line) . '"';
    $conn->errorNum  = $result;

    return $result;
}

function iil_C_Login(&$conn, $user, $password) {

    iil_PutLine($conn->fp, 'a001 LOGIN "'.iil_Escape($user).'" "'.iil_Escape($password).'"');

    do {
        $line = iil_ReadReply($conn->fp);
        if ($line === false) {
            break;
        }
    } while (!iil_StartsWith($line, 'a001 ', true));
    
    // process result
    $result = iil_ParseResult($line);

    if ($result == 0) {
        $conn->error    .= '';
        $conn->errorNum  = 0;
        return $conn->fp;
    }

    fclose($conn->fp);
    
    $conn->error    .= 'Authentication for ' . $user . ' failed (LOGIN): "';
    $conn->error    .= htmlspecialchars($line)."\"";
    $conn->errorNum  = $result;

    return $result;
}

function iil_ParseNamespace2($str, &$i, $len=0, $l) {
	if (!$l) {
	    $str = str_replace('NIL', '()', $str);
	}
	if (!$len) {
	    $len = strlen($str);
	}
	$data      = array();
	$in_quotes = false;
	$elem      = 0;
	for ($i;$i<$len;$i++) {
		$c = (string)$str[$i];
		if ($c == '(' && !$in_quotes) {
			$i++;
			$data[$elem] = iil_ParseNamespace2($str, $i, $len, $l++);
			$elem++;
		} else if ($c == ')' && !$in_quotes) {
			return $data;
    		} else if ($c == '\\') {
			$i++;
			if ($in_quotes) {
				$data[$elem] .= $c.$str[$i];
        		}
		} else if ($c == '"') {
			$in_quotes = !$in_quotes;
			if (!$in_quotes) {
				$elem++;
        		}
		} else if ($in_quotes) {
			$data[$elem].=$c;
		}
	}
	return $data;
}

function iil_C_NameSpace(&$conn) {
	global $my_prefs;

	if (isset($my_prefs['rootdir']) && is_string($my_prefs['rootdir'])) {
    		$conn->rootdir = $my_prefs['rootdir'];
		return true;
	}
	
	if (!iil_C_GetCapability($conn, 'NAMESPACE')) {
	    return false;
	}
    
	iil_PutLine($conn->fp, "ns1 NAMESPACE");
	do {
		$line = iil_ReadLine($conn->fp, 1024);
		if (iil_StartsWith($line, '* NAMESPACE')) {
			$i    = 0;
			$line = iil_UnEscape($line);
			$data = iil_ParseNamespace2(substr($line,11), $i, 0, 0);
		}
	} while (!iil_StartsWith($line, 'ns1', true));
	
	if (!is_array($data)) {
	    return false;
	}
    
	$user_space_data = $data[0];
	if (!is_array($user_space_data)) {
	    return false;
	}
    
	$first_userspace = $user_space_data[0];
	if (count($first_userspace)!=2) {
	    return false;
	}
    
	$conn->rootdir       = $first_userspace[0];
	$conn->delimiter     = $first_userspace[1];
	$my_prefs['rootdir'] = substr($conn->rootdir, 0, -1);
	$my_prefs['delimiter'] = $conn->delimiter;
	
	return true;
}

function iil_Connect($host, $user, $password, $options=null) {	
	global $iil_error, $iil_errornum;
	global $ICL_SSL, $ICL_PORT;
	global $IMAP_NO_CACHE;
	global $my_prefs, $IMAP_USE_INTERNAL_DATE;
	
	$iil_error = '';
	$iil_errornum = 0;

	// set some imap options
	if (is_array($options)) {
		foreach($options as $optkey => $optval) {
			if ($optkey == 'imap') {
				$auth_method = $optval;
			} else if ($optkey == 'rootdir') {
    				$my_prefs['rootdir'] = $optval;
			} else if ($optkey == 'delimiter') {
    				$my_prefs['delimiter'] = $optval;
			}
		}
	}

	if (empty($auth_method))
    		$auth_method = 'check';
		
	$message = "INITIAL: $auth_method\n";
		
	$result = false;
	
	// initialize connection
	$conn              = new iilConnection;
	$conn->error       = '';
	$conn->errorNum    = 0;
	$conn->selected    = '';
	$conn->user        = $user;
	$conn->host        = $host;
	$conn->cache       = array();
	$conn->do_cache    = (function_exists("cache_write")&&!$IMAP_NO_CACHE);
	$conn->cache_dirty = array();
	
	if ($my_prefs['sort_field'] == 'INTERNALDATE') {
		$IMAP_USE_INTERNAL_DATE = true;
	} else if ($my_prefs['sort_field'] == 'DATE') {
    		$IMAP_USE_INTERNAL_DATE = false;
	}
	//echo '<!-- conn sort_field: '.$my_prefs['sort_field'].' //-->';
	
	//check input
	if (empty($host)) {
		$iil_error = "Empty host";
		$iil_errornum = -1;
		return false;
	}
	if (empty($user)) {
		$iil_error = "Empty user";
		$iil_errornum = -1;
		return false;
	}
	if (empty($password)) {
		$iil_error = "Empty password";
		$iil_errornum = -1;
		return false;
	}

	if (!$ICL_PORT) {
		$ICL_PORT = 143;
	}
	//check for SSL
	if ($ICL_SSL && $ICL_SSL != 'tls') {
		$host = $ICL_SSL . '://' . $host;
	}

	$conn->fp = fsockopen($host, $ICL_PORT, $errno, $errstr, 10);
	if (!$conn->fp) {
    		$iil_error = "Could not connect to $host at port $ICL_PORT: $errstr";
    		$iil_errornum = -2;
		return false;
	}

	$iil_error .= "Socket connection established\r\n";
	$line       = iil_ReadLine($conn->fp, 4096);

	// RFC3501 [7.1] optional CAPABILITY response
	if (preg_match('/\[CAPABILITY ([^]]+)\]/i', $line, $matches)) {
		$conn->capability = explode(' ', strtoupper($matches[1]));
	}

	$conn->message .= $line;

	// TLS connection
	if ($ICL_SSL == 'tls' && iil_C_GetCapability($conn, 'STARTTLS')) {
        	if (version_compare(PHP_VERSION, '5.1.0', '>=')) {
               		iil_PutLine($conn->fp, 'stls000 STARTTLS');

			$line = iil_ReadLine($conn->fp, 4096);
                	if (!iil_StartsWith($line, 'stls000 OK')) {
				$iil_error = "Server responded to STARTTLS with: $line";
				$iil_errornum = -2;
                    		return false;
                	}

			if (!stream_socket_enable_crypto($conn->fp, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)) {
				$iil_error = "Unable to negotiate TLS";
				$iil_errornum = -2;
				return false;
			}
			
			// Now we're authenticated, capabilities need to be reread
			iil_C_ClearCapability($conn);
        	}
	}

	if (strcasecmp($auth_method, "check") == 0) {
		//check for supported auth methods
		if (iil_C_GetCapability($conn, 'AUTH=CRAM-MD5') || iil_C_GetCapability($conn, 'AUTH=CRAM_MD5')) {
			$auth_method = 'auth';
		}
		else {
			//default to plain text auth
			$auth_method = 'plain';
		}
	}

	if (strcasecmp($auth_method, 'auth') == 0) {
		$conn->message .= "Trying CRAM-MD5\n";

		//do CRAM-MD5 authentication
		iil_PutLine($conn->fp, "a000 AUTHENTICATE CRAM-MD5");
		$line = trim(iil_ReadLine($conn->fp, 1024));

		$conn->message .= "$line\n";

		if ($line[0] == '+') {
			$conn->message .= 'Got challenge: ' . htmlspecialchars($line) . "\n";

			//got a challenge string, try CRAM-5
			$result = iil_C_Authenticate($conn, $user, $password, substr($line,2));
        		
			// stop if server sent BYE response
			if($result == -3) {
	            		$iil_error = $conn->error;
	            		$iil_errornum = $conn->errorNum;
				return false;
			}
			$conn->message .= "Tried CRAM-MD5: $result \n";
		} else {
			$conn->message .='No challenge ('.htmlspecialchars($line)."), try plain\n";
			$auth = 'plain';
		}
	}
		
	if ((!$result)||(strcasecmp($auth, "plain") == 0)) {
		//do plain text auth
		$result = iil_C_Login($conn, $user, $password);
		$conn->message .= "Tried PLAIN: $result \n";
	}
		
	$conn->message .= $auth;
			
	if (!is_int($result)) {
		iil_C_Namespace($conn);
		return $conn;
	} else {
		$iil_error = $conn->error;
		$iil_errornum = $conn->errorNum;
		return false;
	}
}

function iil_Close(&$conn) {
	iil_C_WriteCache($conn);
	if (iil_PutLine($conn->fp, "I LOGOUT")) {
		fgets($conn->fp, 1024);
		fclose($conn->fp);
		$conn->fp = false;
	}
}

function iil_ClearCache($user, $host) {
}

function iil_C_WriteCache(&$conn) {
	//echo "<!-- doing iil_C_WriteCache //-->\n";
	if (!$conn->do_cache) return false;
	
	if (is_array($conn->cache)) {
		while (list($folder,$data)=each($conn->cache)) {
			if ($folder && is_array($data) && $conn->cache_dirty[$folder]) {
				$key = $folder.".imap";
				$result = cache_write($conn->user, $conn->host, $key, $data, true);
				//echo "<!-- writing $key $data: $result //-->\n";
			}
		}
	}
}

function iil_C_EnableCache(&$conn) {
	$conn->do_cache = true;
}

function iil_C_DisableCache(&$conn) {
	$conn->do_cache = false;
}

function iil_C_LoadCache(&$conn, $folder) {
	if (!$conn->do_cache) {
	    return false;
	}
    
	$key = $folder.'.imap';
	if (!is_array($conn->cache[$folder])) {
		$conn->cache[$folder]       = cache_read($conn->user, $conn->host, $key);
		$conn->cache_dirty[$folder] = false;
	}
}

function iil_C_ExpireCachedItems(&$conn, $folder, $message_set) {
	
	if (!$conn->do_cache) {
		return;	//caching disabled
	}
	if (!is_array($conn->cache[$folder])) {
    		return;	//cache not initialized|empty
	}
	if (count($conn->cache[$folder]) == 0) {
    		return;	//cache not initialized|empty
	}
    
	$uids = iil_C_FetchHeaderIndex($conn, $folder, $message_set, 'UID');
	$num_removed = 0;
	if (is_array($uids)) {
		//echo "<!-- unsetting: ".implode(",",$uids)." //-->\n";
		while (list($n,$uid)=each($uids)) {
			unset($conn->cache[$folder][$uid]);
			//$conn->cache[$folder][$uid] = false;
			//$num_removed++;
		}
		$conn->cache_dirty[$folder] = true;

		//echo '<!--'."\n";
		//print_r($conn->cache);
		//echo "\n".'//-->'."\n";
	} else {
		echo "<!-- failed to get uids: $message_set //-->\n";
	}
	
	/*
	if ($num_removed>0) {
		$new_cache;
		reset($conn->cache[$folder]);
		while (list($uid,$item)=each($conn->cache[$folder])) {
			if ($item) $new_cache[$uid] = $conn->cache[$folder][$uid];
		}
		$conn->cache[$folder] = $new_cache;
	}
	*/
}

function iil_ExplodeQuotedString($delimiter, $string) {
	$quotes = explode('"', $string);
	while ( list($key, $val) = each($quotes)) {
		if (($key % 2) == 1) {
			$quotes[$key] = str_replace($delimiter, "_!@!_", $quotes[$key]);
    		}
	}
	$string = implode('"', $quotes);
	
	$result = explode($delimiter, $string);
	while ( list($key, $val) = each($result) ) {
		$result[$key] = str_replace('_!@!_', $delimiter, $result[$key]);
	}
    
	return $result;
}

function iil_CheckForRecent($host, $user, $password, $mailbox) {
	if (empty($mailbox)) {
		$mailbox = 'INBOX';
	}
    
	$conn = iil_Connect($host, $user, $password, 'plain');
	$fp   = $conn->fp;
	if ($fp) {
		iil_PutLine($fp, "a002 EXAMINE \"".iil_Escape($mailbox)."\"");
		do {
			$line=chop(iil_ReadLine($fp, 300));
			$a=explode(' ', $line);
			if (($a[0] == '*') && (strcasecmp($a[2], 'RECENT') == 0)) {
			    $result = (int) $a[1];
        		}
		} while (!iil_StartsWith($a[0], 'a002', true));

		iil_PutLine($fp, "a003 LOGOUT");
		fclose($fp);
	} else {
	    $result = -2;
	}
    
	return $result;
}

function iil_C_Select(&$conn, $mailbox) {

	if (empty($mailbox)) {
		return false;
	}
	if (strcmp($conn->selected, $mailbox) == 0) {
		return true;
	}
    
	iil_C_LoadCache($conn, $mailbox);
	
	if (iil_PutLine($conn->fp, "sel1 SELECT \"".iil_Escape($mailbox).'"')) {
		do {
			$line = chop(iil_ReadLine($conn->fp, 300));
			$a = explode(' ', $line);
			if (count($a) == 3) {
				if (strcasecmp($a[2], 'EXISTS') == 0) {
					$conn->exists = (int) $a[1];
				}
				if (strcasecmp($a[2], 'RECENT') == 0) {
					$conn->recent = (int) $a[1];
				}
			}
			else if (preg_match('/\[?PERMANENTFLAGS\s+\(([^\)]+)\)\]/U', $line, $match)) {
				$conn->permanentflags = explode(' ', $match[1]);
			}
		} while (!iil_StartsWith($line, 'sel1', true));

		$a = explode(' ', $line);

		if (strcasecmp($a[1], 'OK') == 0) {
			$conn->selected = $mailbox;
			return true;
		}
	}
	return false;
}

function iil_C_CheckForRecent(&$conn, $mailbox) {
	if (empty($mailbox)) {
		$mailbox = 'INBOX';
	}
    
	iil_C_Select($conn, $mailbox);
	if ($conn->selected == $mailbox) {
		return $conn->recent;
	}
	return false;
}

function iil_C_CountMessages(&$conn, $mailbox, $refresh = false) {
	if ($refresh) {
		$conn->selected = '';
	}
	
	iil_C_Select($conn, $mailbox);
	if ($conn->selected == $mailbox) {
		return $conn->exists;
	}
	return false;
}

function iil_SplitHeaderLine($string) {
	$pos=strpos($string, ':');
	if ($pos>0) {
		$res[0] = substr($string, 0, $pos);
		$res[1] = trim(substr($string, $pos+1));
		return $res;
	}
	return $string;
}

function iil_StrToTime($str) {
	$IMAP_MONTHS    = $GLOBALS['IMAP_MONTHS'];
	$IMAP_SERVER_TZ = $GLOBALS['IMAP_SERVER_TZ'];
		
	if ($str) {
    	    $time1 = strtotime($str);
	}
	if ($time1 && $time1 != -1) {
	    return $time1-$IMAP_SERVER_TZ;
	}
	//echo '<!--'.$str.'//-->';
	
	//replace double spaces with single space
	$str = trim($str);
	$str = str_replace('  ', ' ', $str);
	
	//strip off day of week
	$pos = strpos($str, ' ');
	if (!is_numeric(substr($str, 0, $pos))) {
	    $str = substr($str, $pos+1);
	}
	//explode, take good parts
	$a = explode(' ', $str);

	$month_str = $a[1];
	$month     = $IMAP_MONTHS[$month_str];
	$day       = (int)$a[0];
	$year      = (int)$a[2];
	$time      = $a[3];
	$tz_str    = $a[4];
	$tz        = substr($tz_str, 0, 3);
	$ta        = explode(':', $time);
	$hour      = (int)$ta[0]-(int)$tz;
	$minute    = (int)$ta[1];
	$second    = (int)$ta[2];
	
	//make UNIX timestamp
	$time2 = mktime($hour, $minute, $second, $month, $day, $year);
	//echo '<!--'.$time1.' '.$time2.' //-->'."\n";
	return $time2;
}

function iil_C_Sort(&$conn, $mailbox, $field, $add='', $is_uid=FALSE,
    $encoding = 'US-ASCII') {

	$field = strtoupper($field);
	if ($field == 'INTERNALDATE') {
	    $field = 'ARRIVAL';
	}
	
	$fields = array('ARRIVAL' => 1,'CC' => 1,'DATE' => 1,
        'FROM' => 1, 'SIZE' => 1, 'SUBJECT' => 1, 'TO' => 1);
	
	if (!$fields[$field]) {
	    return false;
	}

	/*  Do "SELECT" command */
	if (!iil_C_Select($conn, $mailbox)) {
	    return false;
	}
    
	$is_uid = $is_uid ? 'UID ' : '';
	
	if (!empty($add)) {
	    $add = " $add";
	}

	$command  = 's ' . $is_uid . 'SORT (' . $field . ') ';
	$command .= $encoding . ' ALL' . $add;
	$line     = $data = '';
	
	if (!iil_PutLineC($conn->fp, $command)) {
	    return false;
	}
	do {
		$line = chop(iil_ReadLine($conn->fp, 1024));
		if (iil_StartsWith($line, '* SORT')) {
			$data .= ($data ? ' ' : '') . substr($line, 7);
    		} else if (preg_match('/^[0-9 ]+$/', $line)) {
			$data .= $line;
		}
	} while (!iil_StartsWith($line, 's ', true));
	
	$result_code = iil_ParseResult($line);
	
	if ($result_code != 0) {
                $conn->error = 'iil_C_Sort: ' . $line . "\n";
                return false;
	}
	
	$out = explode(' ',$data);
	return $out;
}

function iil_C_FetchHeaderIndex(&$conn, $mailbox, $message_set, $index_field,
    $normalize=true) {
	global $IMAP_USE_INTERNAL_DATE;
	
	$c=0;
	$result=array();
	$fp = $conn->fp;
		
	if (empty($index_field)) {
	    $index_field = 'DATE';
	}
	$index_field = strtoupper($index_field);
	
	list($from_idx, $to_idx) = explode(':', $message_set);
	if (empty($message_set) || (isset($to_idx)
    	    && (int)$from_idx > (int)$to_idx)) {
		return false;
	}
	
	//$fields_a['DATE'] = ($IMAP_USE_INTERNAL_DATE?6:1);
	$fields_a['DATE']         = 1;
	$fields_a['INTERNALDATE'] = 6;
	$fields_a['FROM']         = 1;
	$fields_a['REPLY-TO']     = 1;
	$fields_a['SENDER']       = 1;
	$fields_a['TO']           = 1;
	$fields_a['SUBJECT']      = 1;
	$fields_a['UID']          = 2;
	$fields_a['SIZE']         = 2;
	$fields_a['SEEN']         = 3;
	$fields_a['RECENT']       = 4;
	$fields_a['DELETED']      = 5;
	
	$mode=$fields_a[$index_field];
	if (!($mode > 0)) {
	    return false;
	}
    
	/*  Do "SELECT" command */
	if (!iil_C_Select($conn, $mailbox)) {
	    return false;
	}
    
	/* FETCH date,from,subject headers */
	if ($mode == 1) {
		$key     = 'fhi' . ($c++);
		$request = $key . " FETCH $message_set (BODY.PEEK[HEADER.FIELDS ($index_field)])";
		if (!iil_PutLine($fp, $request)) {
		    return false;
    		}
		do {
			
			$line=chop(iil_ReadLine($fp, 200));
			$a=explode(' ', $line);
			if (($line[0] == '*') && ($a[2] == 'FETCH')
            		    && ($line[strlen($line)-1] != ')')) {
				$id=$a[1];

				$str=$line=chop(iil_ReadLine($fp, 300));

				while ($line[0] != ')') {					//caution, this line works only in this particular case
					$line=chop(iil_ReadLine($fp, 300));
					if ($line[0] != ')') {
						if (ord($line[0]) <= 32) {			//continuation from previous header line
							$str.= ' ' . trim($line);
						}
						if ((ord($line[0]) > 32) || (strlen($line[0]) == 0)) {
							list($field, $string) = iil_SplitHeaderLine($str);
							if (strcasecmp($field, 'date') == 0) {
								$result[$id] = iil_StrToTime($string);
							} else {
								$result[$id] = str_replace('"', '', $string);
								if ($normalize) {
								    $result[$id] = strtoupper($result[$id]);
                            					}
							}
							$str=$line;
						}
					}
				}
			}
			/*
			$end_pos = strlen($line)-1;
			if (($line[0]=="*") && ($a[2]=="FETCH") && ($line[$end_pos]=="}")) {
				$id = $a[1];
				$pos = strrpos($line, "{")+1;
				$bytes = (int)substr($line, $pos, $end_pos-$pos);
				$received = 0;
				do {
					$line      = iil_ReadLine($fp, 0);
					$received += strlen($line);
					$line      = chop($line);
					
					if ($received>$bytes) {
                    				break;
					} else if (!$line) {
                    				continue;
					}

					list($field, $string) = explode(': ', $line);
					
					if (strcasecmp($field, 'date') == 0) {
						$result[$id] = iil_StrToTime($string);
					} else if ($index_field != 'DATE') {
						$result[$id]=strtoupper(str_replace('"', '', $string));
                			}
				} while ($line[0] != ')');
			} else {
				//one line response, not expected so ignore				
			}
			*/
		} while (!iil_StartsWith($line, $key, true));

	}else if ($mode == 6) {

		$key     = 'fhi' . ($c++);
		$request = $key . " FETCH $message_set (INTERNALDATE)";
		if (!iil_PutLine($fp, $request)) {
		    return false;
    		}
		do {
			$line=chop(iil_ReadLine($fp, 200));
			if ($line[0] == '*') {
				/*
				 * original:
				 * "* 10 FETCH (INTERNALDATE "31-Jul-2002 09:18:02 -0500")"
				 */
				$paren_pos = strpos($line, '(');
				$foo       = substr($line, 0, $paren_pos);
				$a         = explode(' ', $foo);
				$id        = $a[1];
				
				$open_pos  = strpos($line, '"') + 1;
				$close_pos = strrpos($line, '"');
				if ($open_pos && $close_pos) {
					$len         = $close_pos - $open_pos;
					$time_str    = substr($line, $open_pos, $len);
					$result[$id] = strtotime($time_str);
				}
			} else {
				$a = explode(' ', $line);
			}
		} while (!iil_StartsWith($a[0], $key, true));
	} else {
		if ($mode >= 3) {
		    $field_name = 'FLAGS';
		} else if ($index_field == 'SIZE') {
		    $field_name = 'RFC822.SIZE';
		} else {
		    $field_name = $index_field;
    		}
        
		/* 			FETCH uid, size, flags		*/
		$key     = 'fhi' .($c++);
		$request = $key . " FETCH $message_set ($field_name)";

		if (!iil_PutLine($fp, $request)) {
		    return false;
    		}
		do {
			$line=chop(iil_ReadLine($fp, 200));
			$a = explode(' ', $line);
			if (($line[0] == '*') && ($a[2] == 'FETCH')) {
				$line = str_replace('(', '', $line);
				$line = str_replace(')', '', $line);
				$a    = explode(' ', $line);
				
				$id = $a[1];

				if (isset($result[$id])) {
				    continue; //if we already got the data, skip forward
				}
            			if ($a[3]!=$field_name) {
                			continue;  //make sure it's returning what we requested
				}
                
				/*  Caution, bad assumptions, next several lines */
				if ($mode == 2) {
				    $result[$id] = $a[4];
				} else {
					$haystack    = strtoupper($line);
					$result[$id] = (strpos($haystack, $index_field) > 0 ? "F" : "N");
				}
			}
		} while (!iil_StartsWith($line, $key, true));
	}

	//check number of elements...
	list($start_mid, $end_mid) = explode(':', $message_set);
	if (is_numeric($start_mid) && is_numeric($end_mid)) {
		//count how many we should have
		$should_have = $end_mid - $start_mid +1;
		
		//if we have less, try and fill in the "gaps"
		if (count($result) < $should_have) {
			for ($i=$start_mid; $i<=$end_mid; $i++) {
				if (!isset($result[$i])) {
			    		$result[$i] = '';
            			}
        		}
		}
	}
	return $result;	
}

function iil_CompressMessageSet($message_set) {
	//given a comma delimited list of independent mid's, 
	//compresses by grouping sequences together
	
	//if less than 255 bytes long, let's not bother
	if (strlen($message_set)<255) {
	    return $message_set;
	}
    
	//see if it's already been compress
	if (strpos($message_set, ':') !== false) {
	    return $message_set;
	}
    
	//separate, then sort
	$ids = explode(',', $message_set);
	sort($ids);
	
	$result = array();
	$start  = $prev = $ids[0];

	foreach ($ids as $id) {
		$incr = $id - $prev;
		if ($incr > 1) {			//found a gap
			if ($start == $prev) {
			    $result[] = $prev;	//push single id
			} else {
			    $result[] = $start . ':' . $prev;   //push sequence as start_id:end_id
			}
        		$start = $id;			//start of new sequence
		}
		$prev = $id;
	}

	//handle the last sequence/id
	if ($start==$prev) {
	    $result[] = $prev;
	} else {
    	    $result[] = $start.':'.$prev;
	}
    
	//return as comma separated string
	return implode(',', $result);
}

function iil_C_UIDsToMIDs(&$conn, $mailbox, $uids) {
	if (!is_array($uids) || count($uids) == 0) {
	    return array();
	}
	return iil_C_Search($conn, $mailbox, 'UID ' . implode(',', $uids));
}

function iil_C_UIDToMID(&$conn, $mailbox, $uid) {
	$result = iil_C_UIDsToMIDs($conn, $mailbox, array($uid));
	if (count($result) == 1) {
	    return $result[0];
	}
        return false;
}

function iil_C_FetchUIDs(&$conn,$mailbox) {
	global $clock;
	
	$num = iil_C_CountMessages($conn, $mailbox);
	if ($num == 0) {
	    return array();
	}
	$message_set = '1' . ($num>1?':' . $num:'');
	
	//if cache not enabled, just call iil_C_FetchHeaderIndex on 'UID' field
	if (!$conn->do_cache)
		return iil_C_FetchHeaderIndex($conn, $mailbox, $message_set, 'UID');

	//otherwise, let's check cache first
	$key        = $mailbox.'.uids';
	$cache_good = true;
	if ($conn->uid_cache) {
	    $data = $conn->uid_cache;
	} else {
	    $data = cache_read($conn->user, $conn->host, $key);
	}
    
	//was anything cached at all?
	if ($data === false) {
	    $cache_good = -1;
	}
    
	//make sure number of messages were the same
	if ($cache_good > 0 && $data['n'] != $num) {
	    $cache_good = -2;
	}
    
	//if everything's okay so far...
	if ($cache_good > 0) {
		//check UIDs of highest mid with current and cached
		$temp = iil_C_Search($conn, $mailbox, 'UID ' . $data['d'][$num]);
		if (!$temp || !is_array($temp) || $temp[0] != $num) {
		    $cache_good = -3;
    		}
	}

	//if cached data's good, return it
	if ($cache_good > 0) {
		return $data['d'];
	}

	//otherwise, we need to fetch it
	$data      = array('n' => $num, 'd' => array());
	$data['d'] = iil_C_FetchHeaderIndex($conn, $mailbox, $message_set, 'UID');
    
	cache_write($conn->user, $conn->host, $key, $data);
	$conn->uid_cache = $data;
	return $data['d'];
}

function iil_SortThreadHeaders($headers, $index_a, $uids) {
	asort($index_a);
	$result = array();
	foreach ($index_a as $mid=>$foobar) {
		$uid = $uids[$mid];
		$result[$uid] = $headers[$uid];
	}
	return $result;
}

function iil_C_FetchThreadHeaders(&$conn, $mailbox, $message_set) {
	global $clock;
	global $index_a;
	
	list($from_idx, $to_idx) = explode(':', $message_set);
	if (empty($message_set) || (isset($to_idx)
        && (int)$from_idx > (int)$to_idx)) {
		return false;
	}

	$result = array();
	$uids   = iil_C_FetchUIDs($conn, $mailbox);
	$debug  = false;
	
	/* Get cached records where possible */
	if ($conn->do_cache) {
		$cached = cache_read($conn->user, $conn->host, $mailbox.'.thhd');
		if ($cached && is_array($uids) && count($uids)>0) {
			$needed_set = '';
			foreach ($uids as $id=>$uid) {
				if ($cached[$uid]) {
					$result[$uid]     = $cached[$uid];
					$result[$uid]->id = $id;
				} else {
				    $needed_set .= ($needed_set ? ',' : '') . $id;
            			}
			}
			if ($needed_set) {
			    $message_set = $needed_set;
			} else {
			    $message_set = '';
        		}
		}
	}
	$message_set = iil_CompressMessageSet($message_set);
	if ($debug) {
	    echo "Still need: ".$message_set;
	}
    
	/* if we're missing any, get them */
	if ($message_set) {
		/* FETCH date,from,subject headers */
		$key        = 'fh';
		$fp         = $conn->fp;
		$request    = $key . " FETCH $message_set ";
    		$request   .= "(BODY.PEEK[HEADER.FIELDS (SUBJECT MESSAGE-ID IN-REPLY-TO)])";
		$mid_to_id  = array();
		if (!iil_PutLine($fp, $request)) {
		    return false;
    		}
		do {
			$line = chop(iil_ReadLine($fp, 1024));
			if ($debug) {
			    echo $line . "\n";
        		}
			if (ereg('\{[0-9]+\}$', $line)) {
				$a 	 = explode(' ', $line);
				$new = array();

				$new_thhd = new iilThreadHeader;
				$new_thhd->id = $a[1];
				do {
					$line = chop(iil_ReadLine($fp, 1024), "\r\n");
					if (iil_StartsWithI($line, 'Message-ID:')
                    				|| (iil_StartsWithI($line,'In-Reply-To:'))
                    				|| (iil_StartsWithI($line,'SUBJECT:'))) {

						$pos        = strpos($line, ':');
						$field_name = substr($line, 0, $pos);
						$field_val  = substr($line, $pos+1);

						$new[strtoupper($field_name)] = trim($field_val);

					} else if (ereg('^[[:space:]]', $line)) {
						$new[strtoupper($field_name)] .= trim($line);
					}
				} while ($line[0] != ')');
                
				$new_thhd->sbj = $new['SUBJECT'];
				$new_thhd->mid = substr($new['MESSAGE-ID'], 1, -1);
				$new_thhd->irt = substr($new['IN-REPLY-TO'], 1, -1);
				
				$result[$uids[$new_thhd->id]] = $new_thhd;
			}
		} while (!iil_StartsWith($line, 'fh'));
	}
	
	/* sort headers */
	if (is_array($index_a)) {
		$result = iil_SortThreadHeaders($result, $index_a, $uids);	
	}
	
	/* write new set to cache */
	if ($conn->do_cache) {
		if (count($result)!=count($cached)) {
			cache_write($conn->user, $conn->host, $mailbox . '.thhd', $result);
    		}
	}
	
	//echo 'iil_FetchThreadHeaders:'."\n";
	//print_r($result);
	
	return $result;
}

function iil_C_BuildThreads2(&$conn, $mailbox, $message_set, &$clock) {
	global $index_a;

	list($from_idx, $to_idx) = explode(':', $message_set);
	if (empty($message_set) || (isset($to_idx)
    		&& (int)$from_idx > (int)$to_idx)) {
		return false;
	}
    
	$result    = array();
	$roots     = array();
	$root_mids = array();
	$sub_mids  = array();
	$strays    = array();
	$messages  = array();
	$fp        = $conn->fp;
	$debug     = false;
	
	$sbj_filter_pat = '[a-zA-Z]{2,3}(\[[0-9]*\])?:([[:space:]]*)';
	
	/*  Do "SELECT" command */
	if (!iil_C_Select($conn, $mailbox)) {
	    return false;
	}
    
	/* FETCH date,from,subject headers */
	$mid_to_id = array();
	$messages  = array();
	$headers   = iil_C_FetchThreadHeaders($conn, $mailbox, $message_set);
	if ($clock) {
	    $clock->register('fetched headers');
	}
    
	if ($debug) {
	    print_r($headers);
	}
    
	/* go through header records */
	foreach ($headers as $header) {
		//$id = $header['i'];
		//$new = array('id'=>$id, 'MESSAGE-ID'=>$header['m'], 
		//			'IN-REPLY-TO'=>$header['r'], 'SUBJECT'=>$header['s']);
		$id  = $header->id;
		$new = array('id' => $id, 'MESSAGE-ID' => $header->mid, 
        		'IN-REPLY-TO' => $header->irt, 'SUBJECT' => $header->sbj);

		/* add to message-id -> mid lookup table */
		$mid_to_id[$new['MESSAGE-ID']] = $id;
		
		/* if no subject, use message-id */
		if (empty($new['SUBJECT'])) {
		    $new['SUBJECT'] = $new['MESSAGE-ID'];
		}
        
		/* if subject contains 'RE:' or has in-reply-to header, it's a reply */
		$sbj_pre ='';
		$has_re = false;
		if (eregi($sbj_filter_pat, $new['SUBJECT'])) {
		    $has_re = true;
		}
    		if ($has_re||$new['IN-REPLY-TO']) {
        	    $sbj_pre = 'RE:';
		}
        
		/* strip out 're:', 'fw:' etc */
		if ($has_re) {
		    $sbj = ereg_replace($sbj_filter_pat, '', $new['SUBJECT']);
		} else {
		    $sbj = $new['SUBJECT'];
		}
    		$new['SUBJECT'] = $sbj_pre.$sbj;
		
		
		/* if subject not a known thread-root, add to list */
		if ($debug) {
		    echo $id . ' ' . $new['SUBJECT'] . "\t" . $new['MESSAGE-ID'] . "\n";
		}
    		$root_id = $roots[$sbj];
		
		if ($root_id && ($has_re || !$root_in_root[$root_id])) {
			if ($debug) {
			    echo "\tfound root: $root_id\n";
			}
        		$sub_mids[$new['MESSAGE-ID']] = $root_id;
			$result[$root_id][]           = $id;
		} else if (!isset($roots[$sbj]) || (!$has_re && $root_in_root[$root_id])) {
			/* try to use In-Reply-To header to find root 
				unless subject contains 'Re:' */
			if ($has_re&&$new['IN-REPLY-TO']) {
				if ($debug) {
				    echo "\tlooking: ".$new['IN-REPLY-TO']."\n";
				}
				//reply to known message?
				$temp = $sub_mids[$new['IN-REPLY-TO']];
				
				if ($temp) {
					//found it, root:=parent's root
					if ($debug) {
					    echo "\tfound parent: ".$new['SUBJECT']."\n";
					}
                			$result[$temp][]              = $id;
					$sub_mids[$new['MESSAGE-ID']] = $temp;
					$sbj                          = '';
				} else {
					//if we can't find referenced parent, it's a "stray"
					$strays[$id] = $new['IN-REPLY-TO'];
				}
			}
			
			//add subject as root
			if ($sbj) {
				if ($debug) {
				    echo "\t added to root\n";
				}
            			$roots[$sbj]                  = $id;
				$root_in_root[$id]            = !$has_re;
				$sub_mids[$new['MESSAGE-ID']] = $id;
				$result[$id]                  = array($id);
			}
			if ($debug) {
			    echo $new['MESSAGE-ID'] . "\t" . $sbj . "\n";
        		}
		}
	}
	
	//now that we've gone through all the messages,
	//go back and try and link up the stray threads
	if (count($strays) > 0) {
		foreach ($strays as $id=>$irt) {
			$root_id = $sub_mids[$irt];
			if (!$root_id || $root_id==$id) {
			    continue;
			}
        		$result[$root_id] = array_merge($result[$root_id],$result[$id]);
			unset($result[$id]);
		}
	}
	
	if ($clock) {
	    $clock->register('data prepped');
	}
    
	if ($debug) {
	    print_r($roots);
	}

	return $result;
}

function iil_SortThreads(&$tree, $index, $sort_order = 'ASC') {
	if (!is_array($tree) || !is_array($index)) {
	    return false;
	}
    
	//create an id to position lookup table
	$i = 0;
	foreach ($index as $id=>$val) {
		$i++;
		$index[$id] = $i;
	}
	$max = $i+1;
	
	//for each tree, set array key to position
	$itree = array();
	foreach ($tree as $id=>$node) {
		if (count($tree[$id])<=1) {
			//for "threads" with only one message, key is position of that message
			$n         = $index[$id];
			$itree[$n] = array($n=>$id);
		} else {
			//for "threads" with multiple messages, 
			$min   = $max;
			$new_a = array();
			foreach ($tree[$id] as $mid) {
				$new_a[$index[$mid]] = $mid;		//create new sub-array mapping position to id
				$pos                 = $index[$mid];
				if ($pos&&$pos<$min) {
				    $min = $index[$mid];	//find smallest position
				}
			}
			$n = $min;	//smallest position of child is thread position
			
			//assign smallest position to root level key
			//set children array to one created above
			ksort($new_a);
			$itree[$n] = $new_a;
		}
	}
	
	//sort by key, this basically sorts all threads
	ksort($itree);
	$i   = 0;
	$out = array();
	foreach ($itree as $k=>$node) {
		$out[$i] = $itree[$k];
		$i++;
	}
	
	return $out;
}

function iil_IndexThreads(&$tree) {
	/* creates array mapping mid to thread id */
	
	if (!is_array($tree)) {
	    return false;
	}
    
	$t_index = array();
	foreach ($tree as $pos=>$kids) {
		foreach ($kids as $kid) $t_index[$kid] = $pos;
	}
	
	return $t_index;
}

function iil_C_FetchHeaders(&$conn, $mailbox, $message_set, $uidfetch=false, $bodystr=false)
{
	global $IMAP_USE_INTERNAL_DATE;
	
	$result = array();
	$fp     = $conn->fp;
	
	list($from_idx, $to_idx) = explode(':', $message_set);
	if (empty($message_set) || (isset($to_idx)
		&& (int)$from_idx > (int)$to_idx)) {
		return false;
	}
		
	/*  Do "SELECT" command */
	if (!iil_C_Select($conn, $mailbox)) {
		$conn->error = "Couldn't select $mailbox";
		return false;
	}
		
	/* Get cached records where possible */
	if ($conn->do_cache) {
		$uids = iil_C_FetchHeaderIndex($conn, $mailbox, $message_set, "UID");
		if (is_array($uids) && count($conn->cache[$mailbox]>0)) {
			$needed_set = '';
			while (list($id,$uid)=each($uids)) {
				if ($conn->cache[$mailbox][$uid]) {
					$result[$id]     = $conn->cache[$mailbox][$uid];
					$result[$id]->id = $id;
				} else {
				    $needed_set.=($needed_set ? ',': '') . $id;
				}
			}
			//echo "<!-- iil_C_FetchHeader\nMessage Set: $message_set\nNeeded Set:$needed_set\n//-->\n";
			if ($needed_set) {
				$message_set = iil_CompressMessageSet($needed_set);
			} else {
				return $result;
			}
		}
	}

	/* FETCH uid, size, flags and headers */
	$key  	  = 'FH12';
	$request  = $key . ($uidfetch ? ' UID' : '') . " FETCH $message_set ";
	$request .= "(UID RFC822.SIZE FLAGS INTERNALDATE ";
	if ($bodystr)
		$request .= "BODYSTRUCTURE ";
	$request .= "BODY.PEEK[HEADER.FIELDS ";
	$request .= "(DATE FROM TO SUBJECT REPLY-TO IN-REPLY-TO CC BCC ";
	$request .= "CONTENT-TRANSFER-ENCODING CONTENT-TYPE MESSAGE-ID ";
	$request .= "REFERENCES DISPOSITION-NOTIFICATION-TO X-PRIORITY)])";

	if (!iil_PutLine($fp, $request)) {
		return false;
	}
	do {
		$line = iil_ReadLine($fp, 1024);
		$line = iil_MultLine($fp, $line);

		$a    = explode(' ', $line);
		if (($line[0] == '*') && ($a[2] == 'FETCH')) {
			$id = $a[1];
            
			$result[$id]            = new iilBasicHeader;
			$result[$id]->id        = $id;
			$result[$id]->subject   = '';
			$result[$id]->messageID = 'mid:' . $id;

			$lines = array();
			$ln = 0;
			/*
			    Sample reply line:
			    * 321 FETCH (UID 2417 RFC822.SIZE 2730 FLAGS (\Seen)
			    INTERNALDATE "16-Nov-2008 21:08:46 +0100" BODYSTRUCTURE (...)
			    BODY[HEADER.FIELDS ...
			*/

			if (preg_match('/^\* [0-9]+ FETCH \((.*) BODY/s', $line, $matches)) {
				$str = $matches[1];

				// swap parents with quotes, then explode
				$str = eregi_replace("[()]", "\"", $str);
				$a = iil_ExplodeQuotedString(' ', $str);

				// did we get the right number of replies?
				$parts_count = count($a);
				if ($parts_count>=6) {
					for ($i=0; $i<$parts_count; $i=$i+2) {
						if (strcasecmp($a[$i],'UID') == 0)
							$result[$id]->uid = $a[$i+1];
						else if (strcasecmp($a[$i],'RFC822.SIZE') == 0)
							$result[$id]->size = $a[$i+1];
						else if (strcasecmp($a[$i],'INTERNALDATE') == 0)
							$time_str = $a[$i+1];
						else if (strcasecmp($a[$i],'FLAGS') == 0)
							$flags_str = $a[$i+1];
					}

					$time_str = str_replace('"', '', $time_str);
					
					// if time is gmt...
		                        $time_str = str_replace('GMT','+0000',$time_str);
					
					//get timezone
					$time_str      = substr($time_str, 0, -1);
					$time_zone_str = substr($time_str, -5); // extract timezone
					$time_str      = substr($time_str, 0, -5); // remove timezone
					$time_zone     = (float)substr($time_zone_str, 1, 2); // get first two digits
			
					if ($time_zone_str[3] != '0') {
					         $time_zone += 0.5;  //handle half hour offset
					}
					if ($time_zone_str[0] == '-') {
					        $time_zone = $time_zone * -1.0; //minus?
					}
					
					//calculate timestamp
                                        $timestamp     = strtotime($time_str); //return's server's time
					$timestamp    -= $time_zone * 3600; //compensate for tz, get GMT

					$result[$id]->internaldate = $time_str;
					$result[$id]->timestamp = $timestamp;
					$result[$id]->date = $time_str;
				}

				// BODYSTRUCTURE 
				if($bodystr) {
					while (!preg_match('/ BODYSTRUCTURE (.*) BODY\[HEADER.FIELDS/s', $line, $m)) {
						$line2 = iil_ReadLine($fp, 1024);
						$line .= iil_MultLine($fp, $line2);
					}
					$result[$id]->body_structure = $m[1];
				}

				// the rest of the result
				preg_match('/ BODY\[HEADER.FIELDS \(.*\)\]\s*(.*)/s', $line, $m);
				$reslines = explode("\n", trim($m[1], '"'));
				// re-parse (see below)
				foreach ($reslines as $line) {
					if (ord($line[0])<=32) {
						$lines[$ln] .= (empty($lines[$ln])?'':"\n").trim($line);
					} else {
						$lines[++$ln] = trim($line);
					}
				}
			}

			/*
				Start parsing headers.  The problem is, some header "lines" take up multiple lines.
				So, we'll read ahead, and if the one we're reading now is a valid header, we'll
				process the previous line.  Otherwise, we'll keep adding the strings until we come
				to the next valid header line.
			*/
	
			do {
				$line = chop(iil_ReadLine($fp, 300), "\r\n");

				// The preg_match below works around communigate imap, which outputs " UID <number>)".
				// Without this, the while statement continues on and gets the "FH0 OK completed" message.
				// If this loop gets the ending message, then the outer loop does not receive it from radline on line 1249.  
				// This in causes the if statement on line 1278 to never be true, which causes the headers to end up missing
				// If the if statement was changed to pick up the fh0 from this loop, then it causes the outer loop to spin
				// An alternative might be:
				// if (!preg_match("/:/",$line) && preg_match("/\)$/",$line)) break;
				// however, unsure how well this would work with all imap clients.
				if (preg_match("/^\s*UID [0-9]+\)$/", $line)) {
				    break;
				}

				// handle FLAGS reply after headers (AOL, Zimbra?)
				if (preg_match('/\s+FLAGS \((.*)\)\)$/', $line, $matches)) {
					$flags_str = $matches[1];
					break;
				}

				if (ord($line[0])<=32) {
					$lines[$ln] .= (empty($lines[$ln])?'':"\n").trim($line);
				} else {
					$lines[++$ln] = trim($line);
				}
			// patch from "Maksim Rubis" <siburny@hotmail.com>
			} while (trim($line[0]) != ')' && strncmp($line, $key, strlen($key)));

			if (strncmp($line, $key, strlen($key))) { 
				// process header, fill iilBasicHeader obj.
				// initialize
				if (is_array($headers)) {
					reset($headers);
					while (list($k, $bar) = each($headers)) {
						$headers[$k] = '';
					}
				}
	
				// create array with header field:data
				while ( list($lines_key, $str) = each($lines) ) {
					list($field, $string) = iil_SplitHeaderLine($str);
					
					$field  = strtolower($field);
                                        $string = ereg_replace("\n[[:space:]]*"," ",$string); 
					
					switch ($field) {
					case 'date';
						if (!$IMAP_USE_INTERNAL_DATE) {
							$result[$id]->date = $string;
							$result[$id]->timestamp = iil_StrToTime($string);
						}
						break;
					case 'from':
						$result[$id]->from = $string;
						break;
					case 'to':
						$result[$id]->to = preg_replace('/undisclosed-recipients:[;,]*/', '', $string);
						break;
					case 'subject':
						$result[$id]->subject = $string;
						break;
					case 'reply-to':
						$result[$id]->replyto = $string;
						break;
					case 'cc':
						$result[$id]->cc = $string;
						break;
					case 'bcc':
						$result[$id]->bcc = $string;
						break;
					case 'content-transfer-encoding':
						$result[$id]->encoding = $string;
						break;
					case 'content-type':
						$ctype_parts = explode(";", $string);
						$result[$id]->ctype = array_shift($ctype_parts);
						foreach ($ctype_parts as $ctype_add) {
							if (preg_match('/charset="?([a-z0-9\-\.\_]+)"?/i',
								$ctype_add, $regs)) {
								$result[$id]->charset = $regs[1];
							}
						}
						break;
					case 'in-reply-to':
						$result[$id]->in_reply_to = ereg_replace("[\n<>]", '', $string);
						break;
					case 'references':
						$result[$id]->references = $string;
						break;
					case 'return-receipt-to':
					case 'disposition-notification-to':
					case 'x-confirm-reading-to':
						$result[$id]->mdn_to = $string;
						break;
					case 'message-id':
						$result[$id]->messageID = $string;
						break;
					case 'x-priority':
						if (preg_match('/^(\d+)/', $string, $matches))
							$result[$id]->priority = intval($matches[1]);
						break;
					} // end switch ()
				} // end while ()
		
				if ($conn->do_cache) {
					$uid = $result[$id]->uid;
					$conn->cache[$mailbox][$uid] = $result[$id];
					$conn->cache_dirty[$mailbox] = true;
				}
			} else {
				$a = explode(' ', $line);
			}

			// process flags
			if (!empty($flags_str)) {
				$flags_str = eregi_replace('[\\\"]', '', $flags_str);
				$flags_a   = explode(' ', $flags_str);
					
				if (is_array($flags_a)) {
					reset($flags_a);
					while (list(,$val)=each($flags_a)) {
						if (strcasecmp($val,'Seen') == 0) {
						    $result[$id]->seen = true;
						} else if (strcasecmp($val, 'Deleted') == 0) {
						    $result[$id]->deleted=true;
						} else if (strcasecmp($val, 'Recent') == 0) {
						    $result[$id]->recent = true;
						} else if (strcasecmp($val, 'Answered') == 0) {
							$result[$id]->answered = true;
						} else if (strcasecmp($val, '$Forwarded') == 0) {
							$result[$id]->forwarded = true;
						} else if (strcasecmp($val, 'Draft') == 0) {
							$result[$id]->is_draft = true;
						} else if (strcasecmp($val, '$MDNSent') == 0) {
							$result[$id]->mdn_sent = true;
						} else if (strcasecmp($val, 'Flagged') == 0) {
						         $result[$id]->flagged = true;
						}
					}
					$result[$id]->flags = $flags_a;
				}
			}
		}
	} while (strcmp($a[0], $key) != 0);

	return $result;
}

function iil_C_FetchHeader(&$conn, $mailbox, $id, $uidfetch=false, $bodystr=false) {

	$a  = iil_C_FetchHeaders($conn, $mailbox, $id, $uidfetch, $bodystr);
	if (is_array($a)) {
		return array_shift($a);
	}
	return false;
}

function iil_SortHeaders($a, $field, $flag) {
	if (empty($field)) {
	    $field = 'uid';
	}
	$field = strtolower($field);
	if ($field == 'date' || $field == 'internaldate') {
	    $field = 'timestamp';
	}
	if (empty($flag)) {
	    $flag = 'ASC';
	}
    
	$flag     = strtoupper($flag);
	$stripArr = ($field=='subject') ? array('Re: ','Fwd: ','Fw: ','"') : array('"');

	$c=count($a);
	if ($c > 0) {
		/*
			Strategy:
			First, we'll create an "index" array.
			Then, we'll use sort() on that array, 
			and use that to sort the main array.
		*/
                
		// create "index" array
		$index = array();
		reset($a);
		while (list($key, $val)=each($a)) {

			if ($field == 'timestamp') {
				$data = @strtotime($val->date);
				if ($data == false) {
					$data = $val->timestamp;
            			}
			} else {
				$data = $val->$field;
				if (is_string($data)) {
					$data=strtoupper(str_replace($stripArr, '', $data));
            			}
			}
			$index[$key]=$data;
		}
		
		// sort index
		$i = 0;
		if ($flag == 'ASC') {
			asort($index);
    		} else {
        		arsort($index);
		}
        
		// form new array based on index 
		$result = array();
		reset($index);
		while (list($key, $val)=each($index)) {
			$result[$key]=$a[$key];
			$i++;
		}
	}
	
	return $result;
}

function iil_C_Expunge(&$conn, $mailbox) {

	if (iil_C_Select($conn, $mailbox)) {
		$c = 0;
		iil_PutLine($conn->fp, "exp1 EXPUNGE");
		do {
			$line=chop(iil_ReadLine($conn->fp, 100));
			if ($line[0] == '*') {
            			$c++;
        		}
		} while (!iil_StartsWith($line, 'exp1', true));
		
		if (iil_ParseResult($line) == 0) {
			$conn->selected = ''; //state has changed, need to reselect			
			//$conn->exists-=$c;
			return $c;
		}
		$conn->error = $line;
	}
	
	return -1;
}

function iil_C_ModFlag(&$conn, $mailbox, $messages, $flag, $mod) {
	if ($mod != '+' && $mod != '-') {
	    return -1;
	}
    
	$fp    = $conn->fp;
	$flags = $GLOBALS['IMAP_FLAGS'];
        
	$flag = strtoupper($flag);
	$flag = $flags[$flag];
    
	if (iil_C_Select($conn, $mailbox)) {
		$c = 0;
		iil_PutLine($fp, "flg STORE $messages " . $mod . "FLAGS (" . $flag . ")");
		do {
			$line=chop(iil_ReadLine($fp, 100));
			if ($line[0] == '*') {
			    $c++;
        		}
		} while (!iil_StartsWith($line, 'flg', true));

		if (iil_ParseResult($line) == 0) {
			iil_C_ExpireCachedItems($conn, $mailbox, $messages);
			return $c;
		}
		$conn->error = $line;
		return -1;
	}
	$conn->error = 'Select failed';
	return -1;
}

function iil_C_Flag(&$conn, $mailbox, $messages, $flag) {
	return iil_C_ModFlag($conn, $mailbox, $messages, $flag, '+');
}

function iil_C_Unflag(&$conn, $mailbox, $messages, $flag) {
	return iil_C_ModFlag($conn, $mailbox, $messages, $flag, '-');
}

function iil_C_Delete(&$conn, $mailbox, $messages) {
	return iil_C_ModFlag($conn, $mailbox, $messages, 'DELETED', '+');
}

function iil_C_Undelete(&$conn, $mailbox, $messages) {
	return iil_C_ModFlag($conn, $mailbox, $messages, 'DELETED', '-');
}

function iil_C_Unseen(&$conn, $mailbox, $messages) {
	return iil_C_ModFlag($conn, $mailbox, $messages, 'SEEN', '-');
}

function iil_C_Copy(&$conn, $messages, $from, $to) {
	$fp = $conn->fp;

	if (empty($from) || empty($to)) {
	    return -1;
	}
    
	if (iil_C_Select($conn, $from)) {
		$c=0;
		
		iil_PutLine($fp, "cpy1 COPY $messages \"".iil_Escape($to)."\"");
		$line=iil_ReadReply($fp);
		return iil_ParseResult($line);
	} else {
		return -1;
	}
}

function iil_FormatSearchDate($month, $day, $year) {
	$month  = (int) $month;
	$months = $GLOBALS['IMAP_MONTHS'];
	return $day . '-' . $months[$month] . '-' . $year;
}

function iil_C_CountUnseen(&$conn, $folder) {
	$index = iil_C_Search($conn, $folder, 'ALL UNSEEN');
	if (is_array($index)) {
		if (($cnt = count($index)) && $index[0] != '') {
			return $cnt;
		}
	}
	return false;
}

function iil_C_UID2ID(&$conn, $folder, $uid) {
	if ($uid > 0) {
		$id_a = iil_C_Search($conn, $folder, "UID $uid");
		if (is_array($id_a) && count($id_a) == 1) {
			return $id_a[0];
		}
	}
	return false;
}

function iil_C_ID2UID(&$conn, $folder, $id) {
	$fp = $conn->fp;
	if ($id == 0) {
	    return 	-1;
	}
	$result = -1;
	if (iil_C_Select($conn, $folder)) {
		$key = 'FUID';
		if (iil_PutLine($fp, "$key FETCH $id (UID)")) {
			do {
				$line=chop(iil_ReadLine($fp, 1024));
				if (eregi("^\* $id FETCH \(UID (.*)\)", $line, $r)) {
					$result = $r[1];
				}
			} while (!preg_match("/^$key/", $line));
		}
	}
	return $result;
}

function iil_C_Search(&$conn, $folder, $criteria) {
	$fp = $conn->fp;
	if (iil_C_Select($conn, $folder)) {
		$c = 0;
		
		$query = 'srch1 SEARCH ' . chop($criteria);
		if (!iil_PutLineC($fp, $query)) {
			return false;
		}
		do {
			$line=trim(iil_ReadLine($fp, 10000));
			if (eregi("^\* SEARCH", $line)) {
				$str = trim(substr($line, 8));
				$messages = explode(' ', $str);
			}
		} while (!iil_StartsWith($line, 'srch1', true));

		$result_code = iil_ParseResult($line);
		if ($result_code == 0) {
		    return $messages;
		}
		$conn->error = 'iil_C_Search: ' . $line . "\n";
		return false;	
	}
	$conn->error = "iil_C_Search: Couldn't select \"$folder\"\n";
	return false;
}

function iil_C_Move(&$conn, $messages, $from, $to) {
    $fp = $conn->fp;

    if (!$from || !$to) {
        return -1;
    }
    $r = iil_C_Copy($conn, $messages, $from,$to);
    if ($r==0) {
        return iil_C_Delete($conn, $from, $messages);
    }
    return $r;
}

/**
 * Gets the delimiter, for example:
 * INBOX.foo -> .
 * INBOX/foo -> /
 * INBOX\foo -> \
 * 
 * @return mixed A delimiter (string), or false. 
 * @param object $conn The current connection.
 * @see iil_Connect()
 */
function iil_C_GetHierarchyDelimiter(&$conn) {

	global $my_prefs;
	
	if ($conn->delimiter) {
    		return $conn->delimiter;
	}
	if (!empty($my_prefs['delimiter'])) {
    	    return ($conn->delimiter = $my_prefs['delimiter']);
	}
    
	$fp        = $conn->fp;
	$delimiter = false;
	
	//try (LIST "" ""), should return delimiter (RFC2060 Sec 6.3.8)
	if (!iil_PutLine($fp, 'ghd LIST "" ""')) {
	    return false;
	}
    
	do {
		$line=iil_ReadLine($fp, 500);
		if ($line[0] == '*') {
			$line = rtrim($line);
			$a=iil_ExplodeQuotedString(' ', iil_UnEscape($line));
			if ($a[0] == '*') {
			    $delimiter = str_replace('"', '', $a[count($a)-2]);
        		}
		}
	} while (!iil_StartsWith($line, 'ghd', true));

	if (strlen($delimiter)>0) {
	    return $delimiter;
	}

	//if that fails, try namespace extension
	//try to fetch namespace data
	iil_PutLine($conn->fp, "ns1 NAMESPACE");
	do {
		$line = iil_ReadLine($conn->fp, 1024);
		if (iil_StartsWith($line, '* NAMESPACE')) {
			$i = 0;
			$line = iil_UnEscape($line);
			$data = iil_ParseNamespace2(substr($line,11), $i, 0, 0);
		}
	} while (!iil_StartsWith($line, 'ns1', true));
		
	if (!is_array($data)) {
	    return false;
	}
    
	//extract user space data (opposed to global/shared space)
	$user_space_data = $data[0];
	if (!is_array($user_space_data)) {
	    return false;
	}
    
	//get first element
	$first_userspace = $user_space_data[0];
	if (!is_array($first_userspace)) {
	    return false;
	}
    
	//extract delimiter
	$delimiter = $first_userspace[1];	

	return $delimiter;
}

function iil_C_ListMailboxes(&$conn, $ref, $mailbox) {
	global $IGNORE_FOLDERS;
	
	$ignore = $IGNORE_FOLDERS[strtolower($conn->host)];
		
	$fp = $conn->fp;
	
	if (empty($mailbox)) {
	    $mailbox = '*';
	}
	
	if (empty($ref) && $conn->rootdir) {
	    $ref = $conn->rootdir;
	}
    
	// send command
	if (!iil_PutLine($fp, "lmb LIST \"".$ref."\" \"".iil_Escape($mailbox)."\"")) {
	    return false;
	}
    
	$i = 0;
	// get folder list
	do {
		$line = iil_ReadLine($fp, 500);
		$line = iil_MultLine($fp, $line);

		$a = explode(' ', $line);
		if (($line[0] == '*') && ($a[1] == 'LIST')) {
			$line = rtrim($line);
        		// split one line
			$a = iil_ExplodeQuotedString(' ', $line);
        		// last string is folder name
			$folder = trim($a[count($a)-1], '"');
            
        		if (empty($ignore) || (!empty($ignore)
            			&& !eregi($ignore, $folder))) {
            			$folders[$i] = $folder;
        		}
            
		        // second from last is delimiter
        		$delim = trim($a[count($a)-2], '"');
        		// is it a container?
        		$i++;
		}
	} while (!iil_StartsWith($line, 'lmb', true));

	if (is_array($folders)) {
    	    if (!empty($ref)) {
        	// if rootdir was specified, make sure it's the first element
        	// some IMAP servers (i.e. Courier) won't return it
        	if ($ref[strlen($ref)-1]==$delim)
		    $ref = substr($ref, 0, strlen($ref)-1);
    		if ($folders[0]!=$ref)
		    array_unshift($folders, $ref);
    	    }
    	    return $folders;
	} else if (iil_ParseResult($line) == 0) {
		return array('INBOX');
	} else {
		$conn->error = $line;
		return false;
	}
}

function iil_C_ListSubscribed(&$conn, $ref, $mailbox) {
	global $IGNORE_FOLDERS;
	
	$ignore = $IGNORE_FOLDERS[strtolower($conn->host)];
	
	$fp = $conn->fp;
	if (empty($mailbox)) {
		$mailbox = '*';
	}
	if (empty($ref) && $conn->rootdir) {
		$ref = $conn->rootdir;
	}
	$folders = array();

	// send command
	if (!iil_PutLine($fp, 'lsb LSUB "' . $ref . '" "' . iil_Escape($mailbox).'"')) {
		$conn->error = "Couldn't send LSUB command\n";
		return false;
	}
	
	$i = 0;
	
	// get folder list
	do {
		$line = iil_ReadLine($fp, 500);
		$line = iil_MultLine($fp, $line);
		$a    = explode(' ', $line);
        
		if (($line[0] == '*') && ($a[1] == 'LSUB' || $a[1] == 'LIST')) {
			$line = rtrim($line);
            
        		// split one line
			$a = iil_ExplodeQuotedString(' ', $line);
            
        		// last string is folder name
        		//$folder = UTF7DecodeString(str_replace('"', '', $a[count($a)-1]));
        		$folder = trim($a[count($a)-1], '"');
            
			if ((!in_array($folder, $folders)) && (empty($ignore)
            			|| (!empty($ignore) && !eregi($ignore, $folder)))) {
			    $folders[$i] = $folder;
        		}
            
        		// second from last is delimiter
        		$delim = trim($a[count($a)-2], '"');
            
        		// is it a container?
        		$i++;
		}
	} while (!iil_StartsWith($line, 'lsb', true));

	if (is_array($folders)) {
    	    if (!empty($ref)) {
        	// if rootdir was specified, make sure it's the first element
        	// some IMAP servers (i.e. Courier) won't return it
        	if ($ref[strlen($ref)-1]==$delim) {
            	    $ref = substr($ref, 0, strlen($ref)-1);
        	}
        	if ($folders[0]!=$ref) {
            	    array_unshift($folders, $ref);
        	}
    	    }
    	    return $folders;
	}
	$conn->error = $line;
	return false;
}

function iil_C_Subscribe(&$conn, $folder) {
	$fp = $conn->fp;

	$query = 'sub1 SUBSCRIBE "' . iil_Escape($folder). '"';
	iil_PutLine($fp, $query);

	$line = trim(iil_ReadLine($fp, 10000));
	return iil_ParseResult($line);
}

function iil_C_UnSubscribe(&$conn, $folder) {
	$fp = $conn->fp;

	$query = 'usub1 UNSUBSCRIBE "' . iil_Escape($folder) . '"';
	iil_PutLine($fp, $query);
    
	$line = trim(iil_ReadLine($fp, 10000));
	return iil_ParseResult($line);
}

function iil_C_FetchMIMEHeaders(&$conn, $mailbox, $id, $parts) {
	
	$fp     = $conn->fp;

	if (!iil_C_Select($conn, $mailbox)) {
		return false;
	}
	
	$result = false;
	$parts = (array) $parts;
	$key = 'fmh0';
	$peeks = '';
	$idx = 0;

	// format request
	foreach($parts as $part)
		$peeks[] = "BODY.PEEK[$part.MIME]";
	
	$request = "$key FETCH $id (" . implode(' ', $peeks) . ')';

	// send request
	if (!iil_PutLine($fp, $request)) {
	    return false;
	}
        
	do {
        	$line = iil_ReadLine($fp, 1000);
        	$line = iil_MultLine($fp, $line);

		if (preg_match('/BODY\[([0-9\.]+)\.MIME\]/', $line, $matches)) {
			$idx = $matches[1];
			$result[$idx] = preg_replace('/^(\* '.$id.' FETCH \()?\s*BODY\['.$idx.'\.MIME\]\s+/', '', $line);
			$result[$idx] = trim($result[$idx], '"');
	    		$result[$idx] = rtrim($result[$idx], "\t\r\n\0\x0B");
    		}
	} while (!iil_StartsWith($line, $key, true));

	return $result;
}

function iil_C_FetchPartHeader(&$conn, $mailbox, $id, $part) {

	$part = empty($part) ? 'HEADER' : $part.'.MIME';

        return iil_C_HandlePartBody($conn, $mailbox, $id, $part, 1);
}

function iil_C_HandlePartBody(&$conn, $mailbox, $id, $part='', $mode=1, $file=NULL) {
	/* modes:
        1: return string (or write to $file pointer)
        2: print
        3: base64 and print (or write to $file pointer)
	*/
	
	$fp     = $conn->fp;
	$result = false;
	
	if (iil_C_Select($conn, $mailbox)) {
    		$reply_key = '* ' . $id;
        
    		// format request
		$key     = 'ftch' . ($c++) . ' ';
		$request = $key . "FETCH $id (BODY.PEEK[$part])";
    		// send request
		if (!iil_PutLine($fp, $request)) {
		    return false;
    		}
        
    		// receive reply line
    		do {
        		$line = chop(iil_ReadLine($fp, 1000));
        		$a    = explode(' ', $line);
    		} while ($a[2] != 'FETCH');
    		$len = strlen($line);

		// handle empty "* X FETCH ()" response
    		if ($line[$len-1] == ')' && $line[$len-2] != '(') {
        		// one line response, get everything between first and last quotes
			if (substr($line, -4, 3) == 'NIL') {
				// NIL response
				$result = '';
			} else {
			        $from = strpos($line, '"') + 1;
        			$to   = strrpos($line, '"');
		        	$len  = $to - $from;
				$result = substr($line, $from, $len);
			}
	    
	                if ($mode == 2) {
        		        echo $result;
	                } else if ($mode == 3) {
				if ($file)
					fwrite($file, base64_decode($result));
        		    	else
					echo base64_decode($result);
			}			     
    		} else if ($line[$len-1] == '}') {
	                //multi-line request, find sizes of content and receive that many bytes
        		$from     = strpos($line, '{') + 1;
	                $to       = strrpos($line, '}');
        		$len      = $to - $from;
	                $sizeStr  = substr($line, $from, $len);
        		$bytes    = (int)$sizeStr;
			$prev	  = '';
			
        		while ($bytes > 0) {
    		                $line      = iil_ReadLine($fp, 1024);
            			$len       = strlen($line);
                
		                if ($len > $bytes) {
            			        $line = substr($line, 0, $bytes);
		                }
            			$bytes -= strlen($line);

				$line = rtrim($line, "\t\r\n\0\x0B");

		                if ($mode == 1) {
					if ($file)
						fwrite($file, $line . "\n");
            			        else
						$result .= $line . "\n";
		                } else if ($mode == 2) {
            			        echo $line . "\n";
		                } else if ($mode == 3) {
					// create chunks with proper length for base64 decoding
					$line = $prev.$line;
					$length = strlen($line);
					if ($length % 4) {
						$length = floor($length / 4) * 4;
						$prev = substr($line, $length);
						$line = substr($line, 0, $length);
					}
					else
						$prev = '';

					if ($file)
						fwrite($file, base64_decode($line));
            				else
						echo base64_decode($line);
				}
        		}
    		}
	        // read in anything up until last line
		do {
        		$line = iil_ReadLine($fp, 1024);
		} while (!iil_StartsWith($line, $key, true));
        
		if ($mode == 3 && $file) {
			return true;
		}
	
    		if ($result) {
	    		$result = rtrim($result, "\t\r\n\0\x0B");
			if ($file) {
				fwrite($file, $result);
				return true;
			}	
			return $result; // substr($result, 0, strlen($result)-1);
    		}
    		
		return false;
	} else {
		echo 'Select failed.';
	}
    
	if ($mode==1) {
		if ($file) {
			fwrite($file, $result);
			return true;
		}
    		return $result;
	}
	
	return false;
}

function iil_C_FetchPartBody(&$conn, $mailbox, $id, $part, $file=NULL) {
	return iil_C_HandlePartBody($conn, $mailbox, $id, $part, 1, $file);
}

function iil_C_PrintPartBody(&$conn, $mailbox, $id, $part) {
	iil_C_HandlePartBody($conn, $mailbox, $id, $part, 2);
}

function iil_C_PrintBase64Body(&$conn, $mailbox, $id, $part) {
	iil_C_HandlePartBody($conn, $mailbox, $id, $part, 3);
}

function iil_C_CreateFolder(&$conn, $folder) {
	$fp = $conn->fp;
	if (iil_PutLine($fp, 'c CREATE "' . iil_Escape($folder) . '"')) {
		do {
			$line=iil_ReadLine($fp, 300);
		} while ($line[0] != 'c');
        $conn->error = $line;
		return (iil_ParseResult($line) == 0);
	}
	return false;
}

function iil_C_RenameFolder(&$conn, $from, $to) {
	$fp = $conn->fp;
	if (iil_PutLine($fp, 'r RENAME "' . iil_Escape($from) . '" "' . iil_Escape($to) . '"')) {
		do {
			$line = iil_ReadLine($fp, 300);
		} while ($line[0] != 'r');
		return (iil_ParseResult($line) == 0);
	}
	return false;
}

function iil_C_DeleteFolder(&$conn, $folder) {
	$fp = $conn->fp;
	if (iil_PutLine($fp, 'd DELETE "' . iil_Escape($folder). '"')) {
		do {
			$line=iil_ReadLine($fp, 300);
		} while ($line[0] != 'd');
		return (iil_ParseResult($line) == 0);
	}
	$conn->error = "Couldn't send command\n";
	return false;
}

function iil_C_Append(&$conn, $folder, &$message) {
	if (!$folder) {
    		return false;
	}
	$fp = $conn->fp;

	$message = str_replace("\r", '', $message);
	$message = str_replace("\n", "\r\n", $message);		

	$len = strlen($message);
	if (!$len) {
    		return false;
	}

	$request = 'A APPEND "' . iil_Escape($folder) .'" (\\Seen) {' . $len . '}';
    
	if (iil_PutLine($fp, $request)) {
		$line=iil_ReadLine($fp, 100);		
		$sent = fwrite($fp, $message."\r\n");
		do {
			$line=iil_ReadLine($fp, 1000);
		} while ($line[0] != 'A');
	
		$result = (iil_ParseResult($line) == 0);
		if (!$result) {
		    $conn->error .= $line . "\n";
    		}
		return $result;
	}

	$conn->error .= "Couldn't send command \"$request\"\n";
	return false;
}

function iil_C_AppendFromFile(&$conn, $folder, $path) {
	if (!$folder) {
	    return false;
	}
    
	//open message file
	$in_fp = false;				
	if (file_exists(realpath($path))) {
		$in_fp = fopen($path, 'r');
	}
	if (!$in_fp) { 
		$conn->error .= "Couldn't open $path for reading\n";
		return false;
	}
	
	$fp  = $conn->fp;
	$len = filesize($path);
	if (!$len) {
		return false;
	}
    
	//send APPEND command
	$request    = 'A APPEND "' . iil_Escape($folder) . '" (\\Seen) {' . $len . '}';
	$bytes_sent = 0;
	if (iil_PutLine($fp, $request)) {
		$line = iil_ReadLine($fp, 100);
				
		//send file
		while (!feof($in_fp)) {
			$buffer      = fgets($in_fp, 4096);
			$bytes_sent += strlen($buffer);
			iil_PutLine($fp, $buffer, false);
		}
		fclose($in_fp);

		iil_PutLine($fp, '');

		//read response
		do {
			$line = iil_ReadLine($fp, 1000);
		} while ($line[0] != 'A');
			
		$result = (iil_ParseResult($line) == 0);
		if (!$result) {
		    $conn->error .= $line . "\n";
		}
        
		return $result;
	}
	
	$conn->error .= "Couldn't send command \"$request\"\n";
	return false;
}

function iil_C_FetchStructureString(&$conn, $folder, $id) {
	$fp     = $conn->fp;
	$result = false;
	
	if (iil_C_Select($conn, $folder)) {
		$key = 'F1247';

		if (iil_PutLine($fp, "$key FETCH $id (BODYSTRUCTURE)")) {
			do {
				$line = iil_ReadLine($fp, 5000);
				$line = iil_MultLine($fp, $line);
				list(, $index, $cmd, $rest) = explode(' ', $line);
				if ($cmd != 'FETCH' || $index == $id || preg_match("/^$key/", $line))
					$result .= $line;
			} while (!preg_match("/^$key/", $line));

			$result = trim(substr($result, strpos($result, 'BODYSTRUCTURE')+13, -(strlen($result)-strrpos($result, $key)+1)));
		}
	}
	return $result;
}

function iil_C_PrintSource(&$conn, $folder, $id, $part) {
	$header = iil_C_FetchPartHeader($conn, $folder, $id, $part);
	//echo str_replace("\r", '', $header);
	echo $header;
	echo iil_C_PrintPartBody($conn, $folder, $id, $part);
}

function iil_C_GetQuota(&$conn) {
/*
 * GETQUOTAROOT "INBOX"
 * QUOTAROOT INBOX user/rchijiiwa1
 * QUOTA user/rchijiiwa1 (STORAGE 654 9765)
 * OK Completed
 */
	$fp         = $conn->fp;
	$result     = false;
	$quota_lines = array();
	
	// get line(s) containing quota info
	if (iil_PutLine($fp, 'QUOT1 GETQUOTAROOT "INBOX"')) {
		do {
			$line=chop(iil_ReadLine($fp, 5000));
			if (iil_StartsWith($line, '* QUOTA ')) {
				$quota_lines[] = $line;
        		}
		} while (!iil_StartsWith($line, 'QUOT1', true));
	}
	
	// return false if not found, parse if found
	$min_free = PHP_INT_MAX;
	foreach ($quota_lines as $key => $quota_line) {
		$quota_line   = eregi_replace('[()]', '', $quota_line);
		$parts        = explode(' ', $quota_line);
		$storage_part = array_search('STORAGE', $parts);
		
		if (!$storage_part) continue;
	
		$used	= intval($parts[$storage_part+1]);
		$total	= intval($parts[$storage_part+2]);
		$free	= $total - $used; 
	
		// return lowest available space from all quotas
		if ($free < $min_free) { 
		        $min_free = $free; 
			$result['used']    = $used;
			$result['total']   = $total;
			$result['percent'] = min(100, round(($used/max(1,$total))*100));
			$result['free']    = 100 - $result['percent'];
		}
	}
	return $result;
}

function iil_C_ClearFolder(&$conn, $folder) {
	$num_in_trash = iil_C_CountMessages($conn, $folder);
	if ($num_in_trash > 0) {
		iil_C_Delete($conn, $folder, '1:' . $num_in_trash);
	}
	return (iil_C_Expunge($conn, $folder) >= 0);
}

?>