<?php
/**
* Jaxl (Jabber XMPP Library)
*
* Copyright (c) 2009-2012, Abhinav Singh <hide@address.com>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of Abhinav Singh nor the names of his
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRIC
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/

date_default_timezone_set("UTC");
declare(ticks = 1);
define('JAXL_CWD', dirname(__FILE__));

require_once JAXL_CWD.'/core/jaxl_exception.php';
require_once JAXL_CWD.'/core/jaxl_cli.php';
require_once JAXL_CWD.'/core/jaxl_loop.php';
require_once JAXL_CWD.'/xmpp/xmpp_stream.php';
require_once JAXL_CWD.'/core/jaxl_event.php';
require_once JAXL_CWD.'/core/jaxl_logger.php';
require_once JAXL_CWD.'/core/jaxl_socket_server.php';

/**
 * 
 * @author abhinavsingh
 */
class RosterItem {
	
	public $jid = null;
	public $subscription = null;
	public $groups = array();
	public $resources = array();
	public $vcard = null;
	
	public function __construct($jid, $subscription, $groups) {
		$this->jid = $jid;
		$this->subscription = $subscription;
		$this->groups = $groups;
	}
	
}

/**
 * Jaxl class extends base XMPPStream class with following functionalities:
 * 1) Adds an event based wrapper over xmpp stream lifecycle
 * 2) Provides restart strategy and signal handling to ensure connectivity of xmpp stream
 * 3) Roster management as specified in XMPP-IM
 * 4) Management of XEP's inside xmpp stream lifecycle
 * 5) Adds a logging facility
 * 6) Adds a cron job facility in sync with connected xmpp stream timeline
 * 
 * @author abhinavsingh
 *
 */
class JAXL extends XMPPStream {
	
	// lib meta info
	const version = '3.0.0-alpha-1';
	const name = 'JAXL :: Jabber XMPP Library';
	
	// cached init config array
	public $cfg = array();
	
	// event callback engine for xmpp stream lifecycle
	protected $ev = null;
	
	// reference to various xep instance objects
	public $xeps = array();
	
	// local cache of roster list
	public $roster = array();
	
	// whether jaxl must also populate local roster cache with
	// received presence information about the contacts
	public $manage_roster = true;
	
	// what to do with presence sub requests
	// "none" | "accept" | "accept_and_add"
	public $subscription = "none";
	
	// path variables
	public $log_level = JAXL_INFO;
	public $priv_dir;
	public $tmp_dir;
	public $log_dir;
	public $pid_dir;
	public $sock_dir;
	
	// ipc utils
	private $sock;
	private $cli;
	
	// env
	public $local_ip;
	public $pid;
	public $mode;
	
	// current status message
	public $status;
	
	// identity
	public $features = array();
	public $category = 'client';
	public $type = 'bot';
	public $lang = 'en';
	
	// after cth failed attempt
	// retry connect after k * $retry_interval seconds
	// where k is a random number between 0 and 2^c - 1.
	public $retry = true;
	private $retry_interval = 1;
	private $retry_attempt = 0;
	private $retry_max_interval = 32; // 2^5 seconds (means 5 max tries)
	
	public function __construct($config) {
		// env
		$this->cfg = $config;
		$this->mode = PHP_SAPI;
		$this->local_ip = gethostbyname(php_uname('n'));
		$this->pid = getmypid();
		
		// initialize core modules
		$this->ev = new JAXLEvent();
		
		// jid object
		$jid = @$this->cfg['jid'] ? new XMPPJid($this->cfg['jid']) : null;
		
		// handle signals
		if(extension_loaded('pcntl')) {
			pcntl_signal(SIGHUP, array($this, 'signal_handler'));
			pcntl_signal(SIGINT, array($this, 'signal_handler'));
			pcntl_signal(SIGTERM, array($this, 'signal_handler'));
		}
		
		// create .jaxl directory in JAXL_CWD
		// for our /tmp, /run and /log folders
		// overwrite these using jaxl config array
		$this->priv_dir = @$this->cfg['priv_dir'] ? $this->cfg['priv_dir'] : JAXL_CWD."/.jaxl";
		$this->tmp_dir = $this->priv_dir."/tmp";
		$this->pid_dir = $this->priv_dir."/run";
		$this->log_dir = $this->priv_dir."/log";
		$this->sock_dir = $this->priv_dir."/sock";
		if(!is_dir($this->priv_dir)) mkdir($this->priv_dir);
		if(!is_dir($this->tmp_dir)) mkdir($this->tmp_dir);
		if(!is_dir($this->pid_dir)) mkdir($this->pid_dir);
		if(!is_dir($this->log_dir)) mkdir($this->log_dir);
		if(!is_dir($this->sock_dir)) mkdir($this->sock_dir);
		
		// setup logger
		if(isset($this->cfg['log_path'])) JAXLLogger::$path = $this->cfg['log_path'];
		//else JAXLLogger::$path = $this->log_dir."/jaxl.log";
		if(isset($this->cfg['log_level'])) JAXLLogger::$level = $this->log_level = $this->cfg['log_level'];
		else JAXLLogger::$level = $this->log_level;
		
		// touch pid file
		if($this->mode == "cli") {
			touch($this->get_pid_file_path());
			_info("created pid file ".$this->get_pid_file_path());
		}
		
		// include mandatory xmpp xeps
		// service discovery and entity caps
		// are recommended for every xmpp entity
		$this->require_xep(array('0030', '0115'));
		
		// do dns lookup, update $cfg['host'] and $cfg['port'] if not already specified
		$host = @$this->cfg['host']; $port = @$this->cfg['port'];
		if(!$host && !$port && $jid) {
			// this dns lookup is blocking
			_info("dns srv lookup for ".$jid->domain);
			list($host, $port) = JAXLUtil::get_dns_srv($jid->domain);
		}
		$this->cfg['host'] = $host; $this->cfg['port'] = $port;
		
		// choose appropriate transport
		// if 'bosh_url' cfg is defined include 0206
		if(@$this->cfg['bosh_url']) {
			_debug("including bosh xep");
			$this->require_xep('0206');
			$transport = $this->xeps['0206'];
		}
		else {
			list($host, $port) = JAXLUtil::get_dns_srv($jid->domain);
			$stream_context = @$this->cfg['stream_context'];
			$transport = new JAXLSocketClient($stream_context);
		}
		
		// initialize xmpp stream with configured transport
		parent::__construct(
			$transport,
			$jid,
			@$this->cfg['pass'],
			@$this->cfg['resource'] ? 'jaxl#'.$this->cfg['resource'] : 'jaxl#'.md5(time()),
			@$this->cfg['force_tls']
		);
	}
	
	public function __destruct() {
		// delete pid file
		_info("cleaning up pid and unix sock files");
		@unlink($this->get_pid_file_path());
		@unlink($this->get_sock_file_path());
		
		parent::__destruct();
	}
	
	public function get_pid_file_path() {
		return $this->pid_dir."/jaxl_".$this->pid.".pid";
	}
	
	public function get_sock_file_path() {
		return $this->sock_dir."/jaxl_".$this->pid.".sock";
	}
	
	public function require_xep($xeps) {
		if(!is_array($xeps)) 
			$xeps = array($xeps);
		
		foreach($xeps as $xep) {
			$filename = 'xep_'.$xep.'.php';
			$classname = 'XEP_'.$xep;
			
			// include xep
			require_once JAXL_CWD.'/xep/'.$filename;
			$this->xeps[$xep] = new $classname($this);
			
			// add necessary requested callback on events
			foreach($this->xeps[$xep]->init() as $ev=>$cb) {
				$this->add_cb($ev, array($this->xeps[$xep], $cb));
			}
		}
	}
	
	public function add_cb($ev, $cb, $pri=1) {
		return $this->ev->add($ev, $cb, $pri);
	}
	
	public function del_cb($ref) {
		$this->ev->del($ref);
	}
	
	public function set_status($status, $show, $priority) {
		$this->send($this->get_pres_pkt(
			array(),
			$status,
			$show,
			$priority
		));
	}
	
	public function send_chat_msg($to, $body, $thread=null, $subject=null) {
		$msg = new XMPPMsg(
			array(
				'type'=>'chat', 
				'to'=>$to, 
				'from'=>$this->full_jid->to_string()
			), 
			$body,
			$thread,
			$subject
		);
		$this->send($msg);
	}
	
	public function get_vcard($jid=null, $cb=null) {
		$attrs = array(
			'type'=>'get',
			'from'=>$this->full_jid->to_string()
		);
		
		if($jid) {
			$jid = new XMPPJid($jid);
			$attrs['to'] = $jid->node."@".$jid->domain;
		}
		
		$pkt = $this->get_iq_pkt(
			$attrs,
			new JAXLXml('vCard', 'vcard-temp')
		);
		if($cb) $this->add_cb('on_stanza_id_'.$pkt->id, $cb);
		$this->send($pkt);
	}
	
	public function get_roster($cb=null) {
		$pkt = $this->get_iq_pkt(
			array(
				'type'=>'get',
				'from'=>$this->full_jid->to_string()
			),
			new JAXLXml('query', 'jabber:iq:roster')
		);
		if($cb) $this->add_cb('on_stanza_id_'.$pkt->id, $cb);
		$this->send($pkt);
	}
	
	public function start($opts=array()) {
		// is bosh bot?
		if(@$this->cfg['bosh_url']) {
			$this->trans->session_start();
			
			for(;;) {
				// while any of the curl request is pending
				// keep receiving response
				while(sizeof($this->trans->chs) != 0) {
					$this->trans->recv();
				}
				
				// if no request in queue, ping bosh end point
				// and repeat recv
				$this->trans->ping();
			}
			
			$this->trans->session_end();
			return;
		}
		
		// is xmpp client or component?
		// if on_connect event have no callbacks
		// set default on_connect callback to $this->start_stream()
		// i.e. xmpp client mode
		if(!$this->ev->exists('on_connect'))
			$this->add_cb('on_connect', array($this, 'start_stream'));
		
		// connect to the destination host/port
		if($this->connect(($this->cfg['port'] == 5223 ? "ssl" : "tcp")."://".$this->cfg['host'].":".$this->cfg['port'])) {
			// emit
			$this->ev->emit('on_connect');
			
			// parse opts
			if(@$opts['--with-debug-shell']) $this->enable_debug_shell();
			if(@$opts['--with-unix-sock']) $this->enable_unix_sock();
			
			// run main loop
			JAXLLoop::run();
			
			// emit
			$this->ev->emit('on_disconnect');
		}
		// if connection to the destination fails
		else {
			if($this->trans->errno == 61 
			|| $this->trans->errno == 110 
			|| $this->trans->errno == 111
			) {
				$retry_after = pow(2, $this->retry_attempt) * $this->retry_interval;
				$this->retry_attempt++;
				_debug("unable to connect with errno ".$this->trans->errno." (".$this->trans->errstr."), will try again in ".$retry_after." seconds");
				// TODO: use sigalrm instead
				// they usually doesn't gel well inside select loop
				sleep($retry_after);
				$this->start();
			}
			else {
				$this->ev->emit('on_connect_error', array(
					$this->trans->errno,
					$this->trans->errstr
				));
			}
		}
	}
	
	//
	// callback methods
	//
	
	// signals callback handler
	// not for public api consumption
	public function signal_handler($sig) {
		$this->end_stream();
		$this->disconnect();
		$this->ev->emit('on_disconnect');
	
		switch($sig) {
			// terminal line hangup
			case SIGHUP:
				_debug("got sighup");
				break;
				// interrupt program
			case SIGINT:
				_debug("got sigint");
				break;
				// software termination signal
			case SIGTERM:
				_debug("got sigterm");
				break;
		}
	
		exit;
	}
	
	// called internally for ipc
	// not for public consumption
	public function on_unix_sock_accept($_c, $addr) {
		$this->sock->read($_c);
	}
	
	// this currently simply evals the incoming raw string
	// know what you are doing while in production
	public function on_unix_sock_request($_c, $_raw) {
		_debug("evaling raw string rcvd over unix sock: ".$_raw);
		$this->sock->send($_c, serialize(eval($_raw)));
		$this->sock->read($_c);
	}
	
	public function enable_unix_sock() {
		$this->sock = new JAXLSocketServer(
				'unix://'.$this->get_sock_file_path(),
				array(&$this, 'on_unix_sock_accept'),
				array(&$this, 'on_unix_sock_request')
		);
	}
	
	// this simply eval the incoming raw data
	// inside current jaxl environment
	// security is all upto you, no checks made here
	public function handle_debug_shell($_raw) {
		print_r(eval($_raw));
		echo PHP_EOL;
		JAXLCli::prompt();
	}
	
	protected function enable_debug_shell() {
		$this->cli = new JAXLCli(array(&$this, 'handle_debug_shell'));
		JAXLCli::prompt();
	}
	
	//
	// abstract method implementation
	//
	
	protected function send_fb_challenge_response($challenge) {
		$this->send($this->get_fb_challenge_response_pkt($challenge));
	}
	
	// refer https://developers.facebook.com/docs/chat/#jabber
	public function get_fb_challenge_response_pkt($challenge) {
		$stanza = new JAXLXml('response', NS_SASL);
		
		$challenge = base64_decode($challenge);
		$challenge = urldecode($challenge);
		parse_str($challenge, $challenge_arr);
		
		$response = http_build_query(array(
			'method' => $challenge_arr['method'],
			'nonce' => $challenge_arr['nonce'],
			'access_token' => $this->cfg['fb_access_token'],
			'api_key' => $this->cfg['fb_app_key'],
			'call_id' => 0,
			'v' => '1.0'
		));
		
		$stanza->t(base64_encode($response));
		return $stanza;
	}
	
	public function wait_for_fb_sasl_response($event, $args) {
		switch($event) {
			case "stanza_cb":
				$stanza = $args[0];
				
				if($stanza->name == 'challenge' && $stanza->ns == NS_SASL) {
					$challenge = $stanza->text;
					$this->send_fb_challenge_response($challenge);
					return "wait_for_sasl_response";
				}
				else {
					_debug("got unhandled sasl response, should never happen here");
					exit;
				}
				break;
			default:
				_debug("not catched $event, should never happen here");
				exit;
				break;
		}
	}
	
	// someday this needs to go inside xmpp stream
	public function wait_for_cram_md5_response($event, $args) {
		switch($event) {
			case "stanza_cb":
				$stanza = $args[0];
		
				if($stanza->name == 'challenge' && $stanza->ns == NS_SASL) {
					$challenge = base64_decode($stanza->text);
					$resp = new JAXLXml('response', NS_SASL);
					$resp->t(base64_encode($this->jid->to_string().' '.hash_hmac('md5', $challenge, $this->pass)));
					$this->send($resp);
					return "wait_for_sasl_response";
				}
				else {
					_debug("got unhandled sasl response, should never happen here");
					exit;
				}
				break;
			default:
				_debug("not catched $event, should never happen here");
				exit;
				break;
		}
	}
	
	// http://tools.ietf.org/html/rfc5802#section-5
	public function get_scram_sha1_response($pass, $challenge) {
		// it contains users iteration count i and the user salt
		// also server will append it's own nonce to the one we specified
		$decoded = $this->explode_data(base64_decode($challenge));
		
		// r=,s=,i=
		$nonce = $decoded['r'];
		$salt = base64_decode($decoded['s']);
		$iteration = intval($decoded['i']);
		
		// SaltedPassword  := Hi(Normalize(password), salt, i)
		$salted = JAXLUtil::pbkdf2($this->pass, $salt, $iteration);
		// ClientKey       := HMAC(SaltedPassword, "Client Key")
		$client_key = hash_hmac('sha1', $salted, "Client Key", true);
		// StoredKey       := H(ClientKey)
		$stored_key = hash('sha1', $client_key, true);
		// AuthMessage     := client-first-message-bare + "," + server-first-message + "," + client-final-message-without-proof
		$auth_message = '';
		// ClientSignature := HMAC(StoredKey, AuthMessage)
		$signature = hash_hmac('sha1', $stored_key, $auth_message, true);
		// ClientProof     := ClientKey XOR ClientSignature
		$client_proof = $client_key ^ $signature;
		
		$proof = 'c=biws,r='.$nonce.',p='.base64_encode($client_proof);
		return base64_encode($proof);
	}
	
	public function wait_for_scram_sha1_response($event, $args) {
		switch($event) {
			case "stanza_cb":
				$stanza = $args[0];
				
				if($stanza->name == 'challenge' && $stanza->ns == NS_SASL) {
					$challenge = $stanza->text;
					
					$resp = new JAXLXml('response', NS_SASL);
					$resp->t($this->get_scram_sha1_response($this->pass, $challenge));
					$this->send($resp);
					
					return "wait_for_sasl_response";
				}
				else {
					_debug("got unhandled sasl response, should never happen here");
					exit;
				}
				break;
			default:
				_debug("not catched $event, should never happen here");
				exit;
				break;
		}
	}
	
	public function handle_auth_mechs($stanza, $mechanisms) {
		if($this->ev->exists('on_stream_features')) {
			return $this->ev->emit('on_stream_features', array($stanza));
		}
		
		$mechs = array();
		if($mechanisms) foreach($mechanisms->childrens as $mechanism) $mechs[$mechanism->text] = true;
		$pref_auth = @$this->cfg['auth_type'] ? $this->cfg['auth_type'] : 'PLAIN';
		$pref_auth_exists = isset($mechs[$pref_auth]) ? true : false;
		_debug("pref_auth ".$pref_auth." ".($pref_auth_exists ? "exists" : "doesn't exists"));
		
		if($pref_auth_exists) {
			// try prefered auth
			$mech = $pref_auth;
		}
		else {
			// choose one from available mechanisms
			foreach($mechs as $mech=>$any) {
				if($mech == 'X-FACEBOOK-PLATFORM') {
					if(@$this->cfg['fb_access_token']) {
						break;
					}
				}
				else {
					break;
				}
			}
			_error("preferred auth type not supported, trying $mech");
		}
		
		$this->send_auth_pkt($mech, @$this->jid ? $this->jid->to_string() : null, @$this->pass);
		
		if($pref_auth == 'X-FACEBOOK-PLATFORM') {
			return "wait_for_fb_sasl_response";
		}
		else if($pref_auth == 'CRAM-MD5') {
			return "wait_for_cram_md5_response";
		}
		else if($pref_auth == 'SCRAM-SHA-1') {
			return "wait_for_scram_sha1_response";
		}
	}
	
	public function handle_auth_success() {
		// if not a component
		/*if(!@$this->xeps['0114']) {
			$this->xeps['0030']->get_info($this->full_jid->domain, array(&$this, 'handle_domain_info'));
			$this->xeps['0030']->get_items($this->full_jid->domain, array(&$this, 'handle_domain_items'));
		}*/
		
		$this->ev->emit('on_auth_success');
	}
	
	public function handle_auth_failure($reason) {
		$this->ev->emit('on_auth_failure', array(
			$reason
		));
	}
	
	public function handle_stream_start($stanza) {
		$stanza = new XMPPStanza($stanza);
		
		$this->ev->emit('on_stream_start', array($stanza));
		return array(@$this->cfg['bosh_url'] ? 'wait_for_stream_features' : 'connected', 1);
	}
	
	public function handle_iq($stanza) {
		$stanza = new XMPPStanza($stanza);
		
		// emit callback registered on stanza id's
		$emited = false;
		if($stanza->id && $this->ev->exists('on_stanza_id_'.$stanza->id)) {
			//_debug("on stanza id callbackd");
			$emited = true;
			$this->ev->emit('on_stanza_id_'.$stanza->id, array($stanza));
		}
		
		// catch roster list
		if($stanza->type == 'result' && ($query = $stanza->exists('query', 'jabber:iq:roster'))) {
			foreach($query->childrens as $child) {
				if($child->name == 'item') {
					$jid = $child->attrs['jid'];
					$subscription = $child->attrs['subscription'];
					
					$groups = array();
					foreach($child->childrens as $group) {
						if($group->name == 'group') {
							$groups[] = $group->name;
						}
					}
					
					$this->roster[$jid] = new RosterItem($jid, $subscription, $groups);
				}
			}
			
			// emit this event if not emited above
			if(!$emited)
				$this->ev->emit('on_roster_update');
		}
		
		// if managing roster
		// catch contact vcard results
		if($this->manage_roster && $stanza->type == 'result' && ($query = $stanza->exists('vCard', 'vcard-temp'))) {
			if(@$this->roster[$stanza->from])
				$this->roster[$stanza->from]->vcard = $query;
		}
		
		// on_get_iq, on_result_iq, and other events are only
		// emitted if on_stanza_id_{id} wasn't emitted above
		if(!$emited)
			$this->ev->emit('on_'.$stanza->type.'_iq', array($stanza));
	}
	
	public function handle_presence($stanza) {
		$stanza = new XMPPStanza($stanza);
		
		// if managing roster
		// catch available/unavailable type stanza
		if($this->manage_roster) {
			$type = ($stanza->type ? $stanza->type : "available");
			$jid = new XMPPJid($stanza->from);
			
			if($type == 'available') {
				$this->roster[$jid->bare]->resources[$jid->resource] = $stanza;
			}
			else if($type == 'unavailable') {
				if(@$this->roster[$jid->bare] && @$this->roster[$jid->bare]->resources[$jid->resource])
					unset($this->roster[$jid->bare]->resources[$jid->resource]);
			}
		}
		
		$this->ev->emit('on_presence_stanza', array($stanza));
	}
	
	public function handle_message($stanza) {
		$stanza = new XMPPStanza($stanza);
		$this->ev->emit('on_'.$stanza->type.'_message', array($stanza));
	}
	
	// unhandled event and arguments bubbled up
	// TODO: in a lot of cases this will be called, need more checks
	public function handle_other($event, $args) {
		$stanza = $args[0];
		$stanza = new XMPPStanza($stanza);
		$ev = 'on_'.$stanza->name.'_stanza';
		if($this->ev->exists($ev)) {
			return $this->ev->emit($ev, array($stanza));
		}
		else {
			_warning("event '".$event."' catched in handle_other with stanza name ".$stanza->name);
		}
	}
	
	public function handle_domain_info($stanza) {
		$query = $stanza->exists('query', NS_DISCO_INFO);
		foreach($query->childrens as $k=>$child) {
			if($child->name == 'identity') {
				//echo 'identity category:'.@$child->attrs['category'].', type:'.@$child->attrs['type'].', name:'.@$child->attrs['name'].PHP_EOL;
			}
			else if($child->name == 'x') {
				//echo 'x ns:'.$child->ns.PHP_EOL;
			}
			else if($child->name == 'feature') {
				//echo 'feature var:'.$child->attrs['var'].PHP_EOL;
			}
		}
	}
	
	public function handle_domain_items($stanza) {
		$query = $stanza->exists('query', NS_DISCO_ITEMS);
		foreach($query->childrens as $k=>$child) {
			if($child->name == 'item') {
				//echo 'item jid:'.@$child->attrs['jid'].', name:'.@$child->attrs['name'].', node:'.@$child->attrs['node'].PHP_EOL;
			}
		}
	}
	
}

?>