function JLMS_getChatXML($course_id, $group_id, $option, $checked = false)
{
    global $JLMS_DB, $my, $JLMS_CONFIG;
    $do_chat = $checked;
    if (!$do_chat) {
        $JLMS_ACL =& JLMSFactory::getACL();
        if ($JLMS_ACL->CheckPermissions('chat', 'view')) {
            if ($JLMS_ACL->CheckPermissions('chat', 'manage')) {
                if ($group_id) {
                    if ($JLMS_CONFIG->get('use_global_groups', 1)) {
                        $query = "SELECT group_chat FROM #__lms_usergroups WHERE course_id = 0 AND id = {$group_id}";
                        $JLMS_DB->SetQuery($query);
                        if ($JLMS_DB->LoadResult()) {
                            $do_chat = true;
                        }
                    } else {
                        $query = "SELECT group_chat FROM #__lms_usergroups WHERE course_id = {$course_id} AND id = {$group_id}";
                        $JLMS_DB->SetQuery($query);
                        if ($JLMS_DB->LoadResult()) {
                            $do_chat = true;
                        }
                    }
                } else {
                    $do_chat = true;
                }
            } else {
                if ($group_id) {
                    if ($JLMS_CONFIG->get('use_global_groups', 1)) {
                        $query = "SELECT group_chat FROM #__lms_users_in_global_groups AS uigg, #__lms_usergroups AS ug WHERE uigg.user_id = {$my->id} AND uigg.group_id = {$group_id} AND ug.id = uigg.group_id";
                        $JLMS_DB->setQuery($query);
                        if ($JLMS_DB->LoadResult()) {
                            $do_chat = true;
                        }
                    } else {
                        $query = "SELECT b.group_chat FROM #__lms_users_in_groups as a, #__lms_usergroups as b" . "\n WHERE a.course_id = {$course_id} AND a.group_id = {$group_id} AND a.user_id = '" . $my->id . "' AND a.group_id = b.id AND b.id = {$group_id} AND b.course_id = {$course_id}";
                        $JLMS_DB->SetQuery($query);
                        if ($JLMS_DB->LoadResult()) {
                            $do_chat = true;
                        }
                    }
                } else {
                    $do_chat = true;
                }
            }
        }
    }
    if ($do_chat) {
        $last_msg = intval(mosGetParam($_REQUEST, 'last_msg', 0));
        //query (Drop users)
        $tim_minus_15 = time() - date('Z') - 15 * 60;
        $query = "DELETE FROM #__lms_chat_users WHERE time_post < '" . date('Y-m-d H:i:s', $tim_minus_15) . "'";
        $JLMS_DB->SetQuery($query);
        $JLMS_DB->query();
        $query = "SELECT time_enter, time_post FROM #__lms_chat_users" . "\n WHERE user_id = '" . $my->id . "' AND course_id = '" . $course_id . "' AND group_id = '" . $group_id . "'";
        $JLMS_DB->SetQuery($query);
        $XML_data = '';
        $user_time_obj = $JLMS_DB->LoadObject();
        if (is_object($user_time_obj) && isset($user_time_obj->time_enter)) {
            $time_online = $user_time_obj->time_enter;
            $time_prev_post = $user_time_obj->time_post;
            if ($time_online) {
                //query (Update time)
                $query = "UPDATE #__lms_chat_users SET time_post = '" . gmdate('Y-m-d H:i:s') . "'" . "\n WHERE user_id = '" . $my->id . "' AND course_id = '" . $course_id . "' AND group_id = '" . $group_id . "'";
                $JLMS_DB->SetQuery($query);
                $JLMS_DB->query();
                $query = "SELECT a.username FROM #__users as a, #__lms_chat_users as b" . "\n WHERE a.id = b.user_id AND b.course_id = '" . $course_id . "' AND b.group_id = '" . $group_id . "'" . "\n ORDER BY a.username";
                $JLMS_DB->SetQuery($query);
                $chat_users = $JLMS_DB->LoadObjectList();
                $query = "SELECT a.username, b.user_message, b.mes_time, b.id FROM #__users as a, #__lms_chat_history as b" . "\n WHERE a.id = b.user_id AND b.course_id = '" . $course_id . "' AND b.mes_time > '" . $time_online . "'" . "\n AND b.group_id = '" . $group_id . "' AND (b.recv_id = '0' OR b.recv_id = '" . $my->id . "')" . "\n ORDER BY b.mes_time DESC, b.id DESC LIMIT 0, 100";
                $JLMS_DB->SetQuery($query);
                $chat_history = $JLMS_DB->LoadObjectList();
                $new_chat_history = array();
                $time_prev_post_time = strtotime($time_prev_post);
                $do_scroll_chat = false;
                $new_last_id = 0;
                $i = count($chat_history) - 1;
                if (isset($chat_history[0]->mes_time)) {
                    $time_last_post_time = strtotime($chat_history[0]->mes_time);
                    if ($time_last_post_time >= $time_prev_post_time) {
                        $do_scroll_chat = true;
                    }
                }
                while ($i >= 0) {
                    $new_chat_history[] = $chat_history[$i];
                    $i--;
                }
                /* 29.05.2008 - changes by DEN */
                $show_chat_history = array();
                for ($i = 0; $i < count($new_chat_history); $i++) {
                    if ($new_chat_history[$i]->id > $last_msg) {
                        $show_chat_history[] = $new_chat_history[$i];
                        if ($new_chat_history[$i]->id > $new_last_id) {
                            $new_last_id = $new_chat_history[$i]->id;
                        }
                    }
                }
                $count_mes = count($show_chat_history);
                $XML_data .= "\t" . '<task>chat_xml</task>' . "\n";
                $XML_data .= "\t" . '<count_new_msgs>' . $count_mes . '</count_new_msgs>' . "\n";
                $XML_data .= "\t" . '<chat_last_id>' . $new_last_id . '</chat_last_id>' . "\n";
                $XML_data .= "\t" . '<chat_users><![CDATA[' . JLMS_chat_html::prepareUserList($chat_users) . ']]></chat_users>' . "\n";
                //$XML_data .= "\t" . '<chat_history><![CDATA['.JLMS_chat_html::prepareChatHistory($new_chat_history).']]></chat_history>' . "\n";
                $i = 1;
                foreach ($show_chat_history as $data) {
                    $CDATA = '<b>' . $data->username . ': </b><br />';
                    $CDATA .= JLMS_nl2br($data->user_message);
                    $XML_data .= "\t" . '<chat_message_' . $i . '><![CDATA[' . $CDATA . ']]></chat_message_' . $i . '>' . "\n";
                    $i++;
                }
            }
        }
        $iso = explode('=', _ISO);
        echo "\n" . "some notices :)";
        $debug_str = ob_get_contents();
        $debug_str = "no debug info";
        ob_end_clean();
        header('Expires: Fri, 14 Mar 1980 20:53:00 GMT');
        header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . ' GMT');
        header('Cache-Control: no-cache, must-revalidate');
        header('Pragma: no-cache');
        if (class_exists('JFactory')) {
            $document =& JFactory::getDocument();
            $charset_xml = $document->getCharset();
            header('Content-Type: text/xml; charset=' . $charset_xml);
        } else {
            header('Content-Type: text/xml');
        }
        if ($XML_data != "") {
            echo '<?xml version="1.0" encoding="' . $iso[1] . '" standalone="yes"?>';
            echo '<response>' . "\n";
            echo $XML_data;
            echo "\t" . '<debug><![CDATA[' . $debug_str . ']]></debug>' . "\n";
            echo '</response>' . "\n";
        } else {
            echo '<?xml version="1.0" encoding="' . $iso[1] . '" standalone="yes"?>';
            echo '<response>' . "\n";
            echo "\t" . '<task>failed</task>' . "\n";
            echo "\t" . '<info>boom</info>' . "\n";
            echo "\t" . '<debug><![CDATA[' . $debug_str . ']]></debug>' . "\n";
            echo '</response>' . "\n";
        }
    }
    exit;
}
    function showChat($course_id, $group_id, $option, $lists, $chat_users)
    {
        global $Itemid, $JLMS_CONFIG;
        $additon_js = '
var Chat_scroll_obj;
function jlms_prepare_el_Chat_scroll_obj() {
	var Chat_scroll_obj = new Fx.Scroll(\'jlms_chat_window\', {
		wait: false,
		duration: 0,
		offset: {\'x\': 0, \'y\': 0}
	});
	Chat_scroll_obj.toBottom();
}
';
        $JLMS_CONFIG->set('jlms_aditional_js_code', $JLMS_CONFIG->get('jlms_aditional_js_code', '') . $additon_js);
        $domready = '
jlms_prepare_el_Chat_scroll_obj();
';
        $JLMS_CONFIG->set('web20_domready_code', $JLMS_CONFIG->get('web20_domready_code', '') . $domready);
        ?>
<script language="javascript" type="text/javascript">
<!--
var timer_msec = 4000;
var block_chat = 0;
var chat_last_msg = 0;
var ste_k = 2;
var tID = '';
var url_prefix = '<?php 
        echo "index.php?tmpl=component&option={$option}&Itemid={$Itemid}&id={$course_id}&group_id={$group_id}";
        ?>
';
function jlms_MakeRequest(url) {
	var http_request = false;
	if (window.ActiveXObject) { // IE
		try { http_request = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try { http_request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {}
		}
	} else if (window.XMLHttpRequest) { // Mozilla, Safari,...
		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType) {
			http_request.overrideMimeType('text/xml');
		}
	}
	if (!http_request) {
		return false;
	}
	http_request.onreadystatechange = function() { if (window.jlms_AnalizeRequest) {jlms_AnalizeRequest(http_request);} };
	http_request.open('POST', url_prefix, true);
	http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	http_request.setRequestHeader("Content-length", url.length);	
	http_request.send(url);
}
function jlms_AnalizeRequest(http_request) {
	if (http_request.readyState == 4) {
		if ((http_request.status == 200)) {
			block_chat = 0;
			if(http_request.responseXML.documentElement == null){
				try {
					http_request.responseXML.loadXML(http_request.responseText)
				} catch (e) {
					/*alert("Can't load");*/
				}
			}
			response  = http_request.responseXML.documentElement;
			var task = response.getElementsByTagName('task')[0].firstChild.data;
			switch (task) {
				case 'chat_xml':
					//var response_chat = response.getElementsByTagName('chat_history')[0].firstChild.data;
					var response_users = response.getElementsByTagName('chat_users')[0].firstChild.data;
					var chat_last_id = response.getElementsByTagName('chat_last_id')[0].firstChild.data;
					if (parseInt(chat_last_id)) {
						chat_last_msg = parseInt(chat_last_id);
					}
					//var response_do_scroll = response.getElementsByTagName('do_scroll')[0].firstChild.data;

					/*getObj('JLMS_chat_history').innerHTML = response_chat;
					getObj('JLMS_chat_users').innerHTML   = response_users;

					if (response_do_scroll == 1 || response_do_scroll == '1') {
						if ($defined(Chat_scroll_obj)) {
							var type = typeof Chat_scroll_obj;
							if (type == 'object') {
								Chat_scroll_obj.toBottom();
							} else {
								jlms_prepare_el_Chat_scroll_obj();
							}
						} else {
							jlms_prepare_el_Chat_scroll_obj();
						}
					}*/
					var count_new_mess = response.getElementsByTagName('count_new_msgs')[0].firstChild.data;
					if(parseInt(count_new_mess)){
						count_new_mess = parseInt(count_new_mess);
						var el_history = getObj('jlms_chathistory');
						for(var j=1;j < (count_new_mess + 1);j++){
							var message = response.getElementsByTagName('chat_message_'+j)[0].firstChild.data;
							var tbody = new Array();
							tbody = el_history.childNodes;
							for(var i=0;i < tbody.length;i++){
								if(tbody[i].tagName == "TBODY"){
									var el_tbody = tbody[i];	
								}
							}
							var tr_111 = document.createElement("tr");
							var td_111 = document.createElement("td");
							td_111.innerHTML = message;
							tr_111.appendChild(td_111);
							tr_111.className = 'sectiontableentry'+ste_k;
							ste_k = 3 - ste_k;
							el_tbody.appendChild(tr_111);
						}
						/*var scroll_y = parseInt(el_history.offsetHeight);
						document.getElementById("jlms_chat_window").scrollTop = scroll_y;*/
						if ($defined(Chat_scroll_obj)) {
							var type = typeof Chat_scroll_obj;
							if (type == 'object') {
								Chat_scroll_obj.toBottom();
							} else {
								jlms_prepare_el_Chat_scroll_obj();
							}
						} else {
							jlms_prepare_el_Chat_scroll_obj();
						}
					}
					clearTimeout(tID);
					tID = setTimeout("jlms_RequestChatHistory()", timer_msec);
				break;
			}
		} else {
		}
	}
}
function ctrlenter(e){
	$('chat_new_mes').onkeypress = function(event){
		var event = new Event(event);
		if ( ((window.opera || window.gecko) && event.code == '13' && event.control) || ((window.ie || window.webkit) && event.code == '10' && event.control) ){
			jlms_chatPostMessage();
		}
	}
}
function jlms_RequestChatHistory() {
	jlms_MakeRequest('task=get_chat_xml&last_msg='+chat_last_msg);
}
function TRIM_str(sStr) {
	return (sStr.replace(/^[\s\xA0]+/, "").replace(/[\s\xA0]+$/, ""));
}
function URLencode(sStr) {
	return escape(sStr).replace(/\+/g, '%2B').replace(/\"/g,'%22').replace(/\'/g, '%27').replace(/\//g,'%2F');
}
function jlms_chatPostMessage() {
	if (block_chat != 1) {
		clearTimeout(tID);
		var form = document.chatMesForm;
		var user_message = form.chat_new_mes.value;
		if (user_message != '') {
			form.chat_new_mes.value = '';
			if (TRIM_str(user_message) != '') 
			{
				block_chat = 1;				
				jlms_MakeRequest('task=chat_post&last_msg='+chat_last_msg+'&message='+URLencode(TRIM_str(user_message)));
			}
		}
	}
}
//-->
</script>
<?php 
        JLMS_TMPL::OpenMT();
        $hparams = array();
        JLMS_TMPL::ShowHeader('chat', _JLMS_CHAT_TITLE, $hparams);
        JLMS_TMPL::OpenTS();
        ?>
		<noscript>
			<div class="joomlalms_sys_message">
			<?php 
        echo _JLMS_JS_COOKIES_REQUIRES;
        ?>
			</div>
		</noscript>
		<table cellpadding="0" cellspacing="0" border="0" width="100%" class="jlms_table_no_borders">
			<tr>
				<td colspan="2" align="right" style="text-align:right ">
					<form action="<?php 
        echo sefRelToAbs("index.php?option={$option}&Itemid={$Itemid}");
        ?>
" method="post" name="chatForm">
						<?php 
        echo $lists['course_chats'];
        ?>
						<input type="hidden" name="option" value="<?php 
        echo $option;
        ?>
" />
						<input type="hidden" name="Itemid" value="<?php 
        echo $Itemid;
        ?>
" />
						<input type="hidden" name="task" value="chat" />
						<input type="hidden" name="id" value="<?php 
        echo $course_id;
        ?>
" />
					</form>
				</td>
			</tr>
		</table>
		<div style="width:100%; height:400px; overflow:auto; overflow-x:hidden;" id="jlms_chat_window">
		<table cellpadding="0" cellspacing="1" border="0" width="100%" class="<?php 
        echo JLMSCSS::_('jlmslist');
        ?>
">
			<tr>
				<<?php 
        echo JLMSCSS::tableheadertag();
        ?>
 class="<?php 
        echo JLMSCSS::_('sectiontableheader');
        ?>
" width="70%"><?php 
        echo _JLMS_CHAT_TBL_HEAD_CHAT;
        ?>
</<?php 
        echo JLMSCSS::tableheadertag();
        ?>
>
				<<?php 
        echo JLMSCSS::tableheadertag();
        ?>
 class="<?php 
        echo JLMSCSS::_('sectiontableheader');
        ?>
" width="30%"><?php 
        echo _JLMS_CHAT_TBL_HEAD_USERS;
        ?>
</<?php 
        echo JLMSCSS::tableheadertag();
        ?>
>
			</tr>
			<tr>
				<td id="JLMS_chat_history" valign="top" align="left" style="text-align:left;padding:0px;margin:0px;" width="70%">
					<table width="100%" cellpadding="0" cellspacing="0" border="0" id="jlms_chathistory" class="<?php 
        echo JLMSCSS::_('jlmslist');
        ?>
" style="margin:0px; padding:0px;">
						<tr class="<?php 
        echo JLMSCSS::_('sectiontableentry1');
        ?>
"><td align="left"><?php 
        echo _JLMS_CHAT_WELCOME_MESSAGE;
        ?>
</td></tr>
					</table>
				</td>
				<td id="JLMS_chat_users" valign="top" align="left" style="text-align:left;padding:0px;margin:0px;" width="30%">
					<?php 
        echo JLMS_chat_html::prepareUserList($chat_users);
        ?>
				</td>
			</tr>
		</table>
		</div>
		<table cellpadding="0" cellspacing="0" border="0" width="100%" class="jlms_table_no_borders">
			<tr>
				<td>
					<form action="<?php 
        echo sefRelToAbs("index.php?option={$option}&Itemid={$Itemid}");
        ?>
" onsubmit="jlms_chatPostMessage();return false;" method="get" name="chatMesForm">
					<table cellpadding="0" cellspacing="0" border="0" width="100%" class="jlms_table_no_borders">
						<tr>
							<td align="left" width="90%">
								<textarea id="chat_new_mes" name="chat_new_mes" class="inputbox" cols="65" rows="3" style="width:99%; overflow-y:auto; border: 1px solid rgb(198, 198, 198);" onkeypress="ctrlenter(this);"></textarea>
							</td>
							<td align="left" style="padding-left:20px; width:64px;">
								<img class="JLMS_png" src="<?php 
        echo $JLMS_CONFIG->get('live_site');
        ?>
/components/<?php 
        echo $option;
        ?>
/lms_images/send_post_chat.png" border="0" alt="<?php 
        echo _JLMS_CHAT_BTN_POST;
        ?>
" title="<?php 
        echo _JLMS_CHAT_BTN_POST;
        ?>
" onclick="jlms_chatPostMessage();" style="cursor:pointer;"/>
							</td>
						</tr>
					</table>
					</form>
				</td>
			</tr>
		</table>
		<script language="javascript" type="text/javascript">
		<!--
		tID = setTimeout("jlms_RequestChatHistory()", timer_msec);
		//-->
		</script>
<?php 
        JLMS_TMPL::CloseTS();
        JLMS_TMPL::CloseMT();
    }