/**
 * DokuWiki Ajax-Chat plugin
 * AJAX functions
 *
 * @license  GPL2 (http://www.gnu.org/licenses/gpl.html)
 * @author   Pavel Vitis <pavel [dot] vitis [at] seznam [dot] cz>
 */

AJAXCHAT_SHORT_INTERVAL = 5;
AJAXCHAT_MIDDLE_INTERVAL = 10;
AJAXCHAT_LONG_INTERVAL = 30;
AJAXCHAT_MAXIMUM_INTERVAL = 5*60;
AJAXCHAT_CHECKTIMEOUT = 3*1000;
AJAXCHAT_SENDTIMEOUT = 30*1000;
AJAXCHAT_NOMESSAGES = "<em>&ndash; no messages &ndash;</em>";
AJAXCHAT_MESSAGESCLEARED = "<em>&ndash; messages cleared &ndash;</em>";

var ajax_chat = null;

function Mouse_monitor_class(window) {
    this.lastmousex = 0;
    this.lastmousey = 0;
    this.mousemovehooked = false;
    this.mousemoved = false;
    this.window = window;
    this.document = window.document;
    
    var self = this;

    self.onMouseMove = function() {
    };

    self.mouseEvent = function(e) {
		if (false === self.mousemovehooked) {
			return;
		}

		var posx = 0;
		var posy = 0;
		if (!e) {
			var e = self.window.event;
		}
		if (!e) {
			var e = self.document.event;
		}
		if (!e) {
			return;
		}
		if (e.pageX || e.pageY) {
			posx = e.pageX;
			posy = e.pageY;
		}
		else {
			if (e.clientX || e.clientY) {
				posx = e.clientX + self.document.body.scrollLeft;
				posy = e.clientY + self.document.body.scrollTop;
	    	}
		}

		if (self.lastmousex != 0 && self.lastmousey != 0) {
	    	if ((posx == 0 && posy == 0) || posx != self.lastmousex || posy != self.lastmousey) {
				self.mousemoved = true;
				if (self.onMouseMove) {
					try {
						self.onMouseMove();
					} catch (e) {};
				}
				self.onMouseMove = null;
				self.unhookMouseEvent();
//				setTimeout(function(){self.unhookMouseEvent();}, 100);
    	    }
		}

		self.lastmousex = posx;
		self.lastmousey = posy;
    };

    self.hookMouseEvent = function() {
		if (true === self.mousemovehooked) {
			return;
		}
	// Init to current mouse position
		self.mousemoved = false;
//		self.refreshMousePos();
		self.lastmousex = 0;
		self.lastmousey = 0;
		addEvent(self.document, 'mousemove', self.mouseEvent);

		self.mousemovehooked = true;
    };

    self.unhookMouseEvent = function() {
		if (false === self.mousemovehooked) {
			return;
		}

		removeEvent(self.document, 'mousemove', self.mouseEvent);

		self.mousemovehooked = false;
    };

    self.sleep = function(delay) {
	var start = (new Date()).getTime();
	while ((new Date()).getTime() - start < delay) {
	};
    };
}

//prepare class
function Ajax_chat_class(objectName, outId, pageId, lastRefresh, window) {
    this.objectName = objectName;

    this.check_sack = new sack(DOKU_BASE + 'lib/plugins/chat/ajax.php');
    this.check_sack.AjaxFailedAlert = '';
    this.check_sack.encodeURIString = false;

    this.send_sack = new sack(DOKU_BASE + 'lib/plugins/chat/ajax.php');
    this.send_sack.AjaxFailedAlert = '';
    this.send_sack.encodeURIString = false;

    this.timer = null;
    this.lastChatAreaUpdate = new Date().getTime();
    this.chat_timer = null;

    this.outObj = document.getElementById(outId);
    this.pageId = pageId;
    this.lastRefresh = lastRefresh;
    this.lastSend = lastRefresh;
    this.refresh = AJAXCHAT_SHORT_INTERVAL;

    this.clearing = false;
    this.sending = false;

    this.sendQueue = new Array();

    var self = this;

    this.mouseMonitor = new Mouse_monitor_class(window);

    this.onMouseMove = function(func) {
        self.mouseMonitor.onMouseMove = function() {
			func();
//			self.updateInfo('requestTimerInfo', 'mouseMoved'+(new Date()).getTime());
//			self.mouseMonitor.unhookMouseEvent();
		};
		self.mouseMonitor.hookMouseEvent();
    };


    this.check_sack.onLoading = function() {
		self.updateInfo('requestTimerInfo', 'Timer initialized');
		self.check_sack.requestTimer = setTimeout(
	    function() {
//			alert('timeout');
			self.check_sack.requestTimer = null;
			try {
			    if (self.check_sack.xmlhttp.abort) {
					self.check_sack.xmlhttp.abort();
			    }
			} catch (e) {
			}
			self.updateInfo('requestTimerInfo', 'Timeout, aborted connection');
			self.check_sack.onError();
		},
	    AJAXCHAT_CHECKTIMEOUT);
    };

    this.check_sack.onError = function() {
		if (self.check_sack.requestTimer !== null) {
			clearTimeout(self.check_sack.requestTimer);
			self.check_sack.requestTimer = null;
			self.updateInfo('requestTimerInfo', 'Error, timer aborted');
		}
		else {
			self.updateInfo('requestTimerInfo', 'Error, no timer');
		}
        self.updateInfo('ajaxActive','error, waiting');
		self.check_sack.onCompletion();
    };

    this.check_sack.onLoaded = function() {
		if (self.check_sack.requestTimer !== null) {
		    clearTimeout(self.check_sack.requestTimer);
		    self.check_sack.requestTimer = null;
		    self.updateInfo('requestTimerInfo', 'OK, timer cleared');
		}
    };

    this.send_sack.onLoading = function() {
		self.updateInfo('requestTimerInfo', 'Timer initialized');
		self.send_sack.requestTimer = setTimeout(
		    function() {
				self.send_sack.requestTimer = null;
				try {
					if (self.send_sack.xmlhttp.abort) {
						self.send_sack.xmlhttp.abort();
					}
				} catch (e) {
				}
				self.updateInfo('requestTimerInfo', 'Timeout, aborted connection');
				self.send_sack.onError();
			},
	    	AJAXCHAT_SENDTIMEOUT
	    );
    };

    this.send_sack.onError = function() {
		if (self.send_sack.requestTimer !== null) {
		    clearTimeout(self.send_sack.requestTimer);
	    	self.send_sack.requestTimer = null;
			self.updateInfo('requestTimerInfo', 'Error, timer aborted');
		}
		else {
			self.updateInfo('requestTimerInfo', 'Error, no timer');
		}
		self.updateInfo('ajaxActive','error, waiting');
		self.send_sack.onCompletion();
    };

    this.send_sack.onLoaded = function() {
	if (self.send_sack.requestTimer !== null) {
	    clearTimeout(self.send_sack.requestTimer);
	    self.send_sack.requestTimer = null;
	    self.updateInfo('requestTimerInfo', 'OK, timer cleared');
	}
//	if (200 != self.send_sack.responseStatus[0]*1) {
//	    self.send_sack.onCompletion();
//	}
    };

    this.getUpdateTimeFromResponse = function(resp) {
	var time = resp.substring(0, resp.indexOf('\n')).replace(/(.*<!--AJAXCHAT_MTIME:)([0-9]+)(-->.*)/, '$2');
//	alert(time*1);
	if (time == null || time == '') {
	    time = 0;
	}
	return time*1;
    };

    self.updateInfo('ajaxRefreshInterval', this.refresh+'sec');
}

Ajax_chat_class.prototype.updateInfo = function(infoTag, infoValue) {
    var infoDiv = document.getElementById('chat-info-pad');
    if (infoDiv) {
		if (infoDiv.elements[infoTag]) {
			infoDiv.elements[infoTag].value = infoValue;
		}
    }
};

Ajax_chat_class.prototype.chatClear = function(user) {
    var self = this;
    self.clearing = true;

//    self.chatCheckAbort();

    self.send_sack.oldOnError = self.send_sack.onError;
    self.send_sack.onError = function() {
	self.send_sack.oldOnError();
        self.clearing = false;
	self.send_sack.onError = self.send_sack.oldOnError;
//	alert('onerror');
    };

    this.send_sack.onCompletion = function() {
	var data = self.send_sack.response;
	if (data !== '') {
    	    self.updateInfo('ajaxLastStatus','Messages cleared');

	    self.outObj.innerHTML = AJAXCHAT_MESSAGESCLEARED;
	    self.outObj.style.display = 'block';
	    updated = self.getUpdateTimeFromResponse(data);
	    self.lastRefresh = updated;//((new Date().getTime())/1000);
	    self.clearing = false;
	    self.send_sack.onError = self.send_sack.oldOnError;
	}
    };

    self.outObj.innerHTML = AJAXCHAT_MESSAGESCLEARED;
    
    if (this.send_sack.encVar) {
	this.send_sack.encVar('call', 'clear');
	this.send_sack.encVar('pageId', self.pageId);
	this.send_sack.encVar('time', self.lastRefresh);
	this.send_sack.encVar('user', user);
	this.send_sack.runAJAX();
    }
    else {    
	this.send_sack.runAJAX(
		'call=clear'+
		'&pageId='+encodeURIComponent(this.pageId)+
		'&time='+this.lastRefresh+
		'&user='+encodeURIComponent(user));
    }		
};

Ajax_chat_class.prototype.chatSend = function(user,message) {
    var self = this;

    if (true == self.clearing) {
	return;
    }

    self.sending = true;

//    self.chatCheckAbort();

//    sleep(1000);

    self.send_sack.oldOnError = self.send_sack.onError;
    self.send_sack.onError = function() {
	if (self.send_sack.onError !== self.send_sack.oldOnError) {
	    self.send_sack.oldOnError();
	}    
	self.sending = false;
	self.send_sack.onError = self.send_sack.oldOnError;
//		alert('onerror');
    };

    this.send_sack.onCompletion = function() {
		var data = self.send_sack.response;
		if (200 == self.send_sack.responseStatus[0]*1) {
//			alert(data);
		    var sentDiv = document.getElementById('chatListSentMessage');
		    if (sentDiv) {
			sentDiv.innerHTML = '';
			sentDiv.style.display = 'none';
		    }
		    if (data !== '') {
			var updated = self.getUpdateTimeFromResponse(data);
			var actualData = data.replace(/[^\n]+\n[ ]*/,'');
			if (actualData.length == 0) {
			//    alert(data);
			}
			self.outObj.innerHTML = 
				(actualData.length > 0 ? actualData+(self.lastRefresh > 0 ? self.outObj.innerHTML : '') : AJAXCHAT_NOMESSAGES);
			self.outObj.style.display = 'block';
			self.lastRefresh = updated;//((new Date().getTime())/1000);
			self.lastSend = updated;

			// remove first message from queue
			self.sendQueue.shift();
		    }

		    
		}
		else {
//	    	alert(data);
//		    alert(self.send_sack.responseStatus[0]*1);
		}
/*		
		if (self.sendQueue !== null && self.sendQueue.length > 0) {
		    var msgrec = self.sendQueue[0];
			
		    self.send_sack.runAJAX(
		        'call=send'+
		        '&pageId='+encodeURIComponent(self.pageId)+
		        '&time='+self.lastRefresh+
		        '&user='+encodeURIComponent(msgrec[0])+
		        '&msg='+encodeURIComponent(msgrec[1]));
		}
		
		else 
*/
		{
		    self.sending = false;
		    self.send_sack.onError = self.send_sack.oldOnError;
		}
    };

    this.requestTimeout = AJAXCHAT_SENDTIMEOUT;

    // add message to send queue
    var msgrec = new Array();
    msgrec[0] = user;
    msgrec[1] = message;
//    self.sendQueue.push(msgrec);

    if (this.send_sack.encVar) {
	this.send_sack.encVar('call', 'send');
	this.send_sack.encVar('pageId', self.pageId);
	this.send_sack.encVar('time', self.lastRefresh);
	this.send_sack.encVar('user', user);
	this.send_sack.encVar('msg', message);
	this.send_sack.runAJAX();
    }
    else {    
	this.send_sack.runAJAX(
	    'call=send'+
	    '&pageId='+encodeURIComponent(self.pageId)+
	    '&time='+self.lastRefresh+
	    '&user='+encodeURIComponent(user)+
	    '&msg='+encodeURIComponent(message));
    }
};

Ajax_chat_class.prototype.chatCheck = function() {
    try {
//    alert(this);
    var self = this;

    if (true == self.sending) {
	return;
    }

    if (self.chat_timer !== null) {
	clearTimeout(self.chat_timer);
	self.chat_timer = null;
    }

    this.check_sack.onCompletion = function() {
		if (true == self.clearing || true == self.sending) {
		    return;
		}

		var data = self.check_sack.response;

		if (200 != self.check_sack.responseStatus[0]*1) {
			self.updateInfo('ajaxActive','waiting');
			self.updateInfo('ajaxLastStatus','Error '+self.check_sack.responseStatus[0]+', waiting');
		}
		else {
			self.updateInfo('ajaxActive','waiting');

			if(data === '') {
				self.updateInfo('ajaxLastStatus','No change');
		    }
		    else {
				var updated = self.getUpdateTimeFromResponse(data);
				if ((updated == 0 || updated > self.lastRefresh) && false == self.clearing && false == self.sending) {
					var actualData = data.replace(/[^\n]+\n[ ]*/,'');
					if (actualData !== self.lastMessage) {
					    self.outObj.innerHTML = 
						(actualData.length > 0 ? actualData+(self.lastRefresh > 0 ? self.outObj.innerHTML : '') : AJAXCHAT_NOMESSAGES);
					    self.outObj.style.display = 'block';
//				    alert(updated);
//				    alert(((new Date().getTime())/1000));
	    				    self.updateInfo('ajaxLastStatus','New messages fetched');
					    if (actualData.length > 0) {
						chatNotifySound();
					    }
					    else {
					    }
					    self.lastMessage = actualData;
					}
					self.lastRefresh = updated;//((new Date().getTime())/1000);
				}
			}
		}
    };

    this.updateInfo('ajaxActive','checking...');

//    alert(self.lastRefresh);
    if (self.check_sack.encVar) {
	self.check_sack.encVar('call', 'checkAndGet');
	self.check_sack.encVar('pageId', self.pageId);
	self.check_sack.encVar('time', self.lastRefresh);
	self.check_sack.runAJAX();
    }
    else {    
	self.check_sack.runAJAX(
		'call=checkAndGet&pageId='+encodeURIComponent(self.pageId)+'&time='+self.lastRefresh);
    }
    
    var now = new Date().getTime();
    if ((now - self.lastChatAreaUpdate)/1000 >= 5*60) {
		self.refresh = AJAXCHAT_MAXIMUM_INTERVAL;
		self.updateInfo('ajaxRefreshInterval',self.refresh+'sec');
    }
    else {
		if ((now - self.lastChatAreaUpdate)/1000 >= 60) {
			self.refresh = AJAXCHAT_LONG_INTERVAL;
			self.updateInfo('ajaxRefreshInterval',self.refresh+'sec');

			self.onMouseMove(function(){
				if (self.refresh > AJAXCHAT_MIDDLE_INTERVAL) {
//	    			alert(self.refresh);
					self.refresh = AJAXCHAT_MIDDLE_INTERVAL;
					self.lastChatAreaUpdate = new Date().getTime()-(30*1000);
					self.updateInfo('ajaxRefreshInterval',self.refresh+'sec');
//					self.chatCheck();
					self.chat_timer = setTimeout(self.objectName+".chatCheck()", 100);
				}
			});
		}
		else {
			if ((now - self.lastChatAreaUpdate)/1000 >= 30) {
				self.refresh = AJAXCHAT_MIDDLE_INTERVAL;
				self.updateInfo('ajaxRefreshInterval',self.refresh+'sec');
    	    }
		}
    }

    // Add fuzziness to timer to avoid high loads on server at the same time from multiple clients
    var timeoutFuzzy =
		(Math.round(Math.random()) > 0 ? 1 : -1) *
		Math.round(Math.random()*((self.refresh*1000)/10));
	self.updateInfo('ajaxNextCheck', 'Next check: ' + self.refresh + 's  ' +
		(timeoutFuzzy > 0 ? "+"+timeoutFuzzy+"ms" :
		timeoutFuzzy < 0 ? timeoutFuzzy+"ms" : ""));

    } catch (e) {
    }

    // Set new timer
    self.chat_timer = setTimeout(self.objectName+".chatCheck()", (self.refresh*1000) + timeoutFuzzy);
};

Ajax_chat_class.prototype.chatCheckAbort = function() {
    var self = this;
    if (null != self.check_sack.requestTimer) {
	clearTimeout(self.check_sack.requestTimer);
	self.check_sack.requestTimer = null;
        this.updateInfo('ajaxActive','aborted check...');
    }

    if (self.check_sack.xmlhttp && self.check_sack.xmlhttp.abort) {
	try {
//	    self.check_sack.resetData();
	    self.check_sack.xmlhttp.abort();
//	    alert('aborted');
	} catch (e) {
	}
    }
};

function chatSetCookie(name, value, expire) {
    try {
	// New code
	DokuCookie.setValue(name, value, expire);
    } catch (e) {
	// Old code
        var expiref = new Date();
	fixDate(expiref);
        expiref.setTime(expiref.getTime() + expire);
	setCookie(name, value, expiref);
    }
}

function chatGetCookie(name) {
    var value;
    try {
	// New code
	value = DokuCookie.getValue(name);
    } catch (e) {
	// Old code
	value = getCookie(name);	
    }
    return value;
}

function new_ajax_chat(outId, pageId, lastRefresh) {
    ajax_chat = new Ajax_chat_class("ajax_chat", outId, pageId, lastRefresh, window);
}

function chatRefresh(event) {
    if (ajax_chat === null) {
		return;
    }

    var list = document.getElementById('chat-last-message');
    if (list) {
		if (list.className.indexOf(' chat-line-last') != -1) {
		    list.className = list.className.replace(/ chat-line-last/gi, '');
		}
    }

    ajax_chat.chatCheck();
}

function chatClick(event) {
    if (ajax_chat === null) {
	return;
    }

    if (ajax_chat.refresh > AJAXCHAT_SHORT_INTERVAL) {
	ajax_chat.refresh = AJAXCHAT_SHORT_INTERVAL;
	ajax_chat.lastChatAreaUpdate = (new Date()).getTime();
	ajax_chat.updateInfo('ajaxRefreshInterval',ajax_chat.refresh+'sec');
    }
    
    chatRefresh();
}

function chatAreaUpdated(event) {
    if (ajax_chat === null) {
	return;
    }

    var now = new Date().getTime();

    if ((now - ajax_chat.lastChatAreaUpdate)/1000 < 30) {
		if (ajax_chat.refresh > AJAXCHAT_SHORT_INTERVAL) {
			ajax_chat.refresh = AJAXCHAT_SHORT_INTERVAL;
			ajax_chat.updateInfo('ajaxRefreshInterval',ajax_chat.refresh+'sec');
			chatRefresh();
		}
		else {
		}
    }
    else {
        chatRefresh();
    }

    ajax_chat.lastChatAreaUpdate = now;
}

function chatSendMessage(user,msg) {
    // do not allow to send more than 1 message per second
    if (ajax_chat.lastSend > 0) {
	var now = (new Date()).getTime();
	if (now - (ajax_chat.lastSend*1000) < 1000) {
	    return false;
//	    ajax_chat.sleep(now - (ajax_chat.lastSend*1000));
	}
    }

    // format date-time    
    var time = new Date();
    var timeF;
    if ((''+time.getHours()).length > 1) {
	timeF = time.getHours()+":";
    }
    else {
	timeF = "0"+time.getHours()+":";
    }
    if ((''+time.getMinutes()).length > 1) {
	timeF += time.getMinutes()+":";
    }
    else {
	timeF += "0"+time.getMinutes()+":";
    }
    if ((''+time.getSeconds()).length > 1) {
	timeF += time.getSeconds()+"";
    }
    else {
	timeF += "0"+time.getSeconds()+"";
    }

    var list = document.getElementById('chatListSentMessage');

    // format message
    list.innerHTML = "<strong>" +
	user + "</strong> (" +
	timeF+
	"): <br /><blockquote>" + msg + "</blockquote>\n";

    // show sent-message div
    list.style.display = 'block';
    list.style.height = '';
    
    // do real sending
    ajax_chat.chatSend(user,msg);

    return true;
}

function focusChatPrompt() {
    var form = document.getElementById('chatForm');
    if (form) {
	if (form.chatMessage) {
	    form.chatMessage.focus();
	}
    }
}

function chatClearMessages(user) {
    var list = document.getElementById('chatList');
    list.innerHTML = "&nbsp;";
    ajax_chat.chatClear(user);
    focusChatPrompt();
}

function chatEventKeyUp() {
    var input = document.getElementById('chatForm').chatMessage;
}

function chatEventClear() {
    var form = document.getElementById('chatForm');

    chatClearMessages(form.user.value);

    return false;
}

function chatEventSubmit() {
    try {
	focusChatPrompt();

	var form = document.getElementById('chatForm');
        if (form.chatMessage.value === '') {
	    return false;
	}

	if (chatSendMessage(form.user.value, form.chatMessage.value)) {
	    form.chatMessage.value = '';
	}
    } catch (e) {
    };
    return false;
}
/*
function chatEventMouseMove(e) {
    if (ajax_chat.refresh > AJAXCHAT_MIDDLE_INTERVAL) {
	ajax_chat.refresh = AJAXCHAT_MIDDLE_INTERVAL;
	ajax_chat.updateInfo('ajaxRefreshInterval',ajax_chat.refresh+'sec');
        ajax_chat.lastChatAreaUpdate = new Date().getTime()-(30*1000);
	ajax_chat.chatCheck();
    }
}
*/
function saveChatUser() {
    var input = document.getElementById('chatForm').user;
    if (!input) {
	return;
    }

    if (null !== input.timer) {
	clearTimeout(input.timer);
	input.timer = null;
    }

    input.lastKey = null;

    chatSetCookie('chatName', input.value, 365*24*60*60*1000);
}

function chatEventUserChanged(e) {
    var input = document.getElementById('chatForm').user;
    if (!input) {
	return;
    }

    if (null !== input.timer) {
	clearTimeout(input.timer);
        input.timer = null;
    }

    var now = new Date();
    if (!input.lastKey) {
	input.lastKey = now.getTime();

        input.timer = setTimeout('saveChatUser()', 1000);
    }
    else {
	input.lastKey = now.getTime();
        input.timer = setTimeout('saveChatUser()', 1000);
    }
}

function chatNotifySound() {
    var soundPlayer = document.getElementById('newmsg_sound');
    if (soundPlayer) {
	try {
	    soundPlayer.play();
	} catch (e) {};
    }
}

function chatSetVolume(vol,silent,cookie) {
    var soundPlayer = document.getElementById('newmsg_sound');
    if (soundPlayer) {
	try {
	    soundPlayer.setVolume(vol);
	    if (!silent && (vol > 0)) {
		soundPlayer.play();
	    }
	    var img = document.getElementById('chatVolumeIcon');
	    if (img) {
		img.src = DOKU_BASE+'lib/plugins/chat/volume'+vol+'.gif';
		img.title = 'Set notify volume ('+(vol > 0 ? vol : 'muted')+')';
		img.style.width = '';
		img.style.paddingRight = '10px';
		img.style.paddingTop = '2px';
	    }
	} catch (e) {};
        if (cookie) {	
    	    chatSetCookie('chatVolume', vol+'', 365*24*60*60*1000);
	}
    }
}

function chatToggleVolume() {
    var soundPlayer = document.getElementById('newmsg_sound');
    if (soundPlayer) {
	try {
	    var volume = soundPlayer.getVolume()+1;
	    if (volume > 4) {
	    	volume = 0;
	    }
	    chatSetVolume(volume,false,true);
	} catch (e) {};
    }
}

function chatInitialize() {
    var form = document.getElementById('chatForm');
    var list = document.getElementById('chatList');

    if (form) {
	if (form.user && 'text' == form.user.type) {
	    var cname = chatGetCookie('chatName');
	    if (null !== cname) {
		form.user.value = cname;
	    }
	    else {
		saveChatUser();
	    }
	}

	if (form.chatMessage) {
	    addEvent(form, 'submit', chatEventSubmit);
	    addEvent(form.user, 'keyup', chatEventUserChanged);
	    addEvent(form.chatMessage, 'keyup', chatAreaUpdated);
	    setTimeout('focusChatPrompt()', 1000);
	}
	if (form.clearButton) {
	    addEvent(form.clearButton, 'click', chatEventClear);
	}

	new_ajax_chat('chatList', form.pageId.value, 0);
	ajax_chat.chatCheck();
    }
    
    if (list) {
	addEvent(list, 'mouseup', chatClick);
    }
    
}

(function(){

//preload images
(new Image()).src = DOKU_BASE+'lib/plugins/chat/volume0.gif';
(new Image()).src = DOKU_BASE+'lib/plugins/chat/volume1.gif';
(new Image()).src = DOKU_BASE+'lib/plugins/chat/volume2.gif';
(new Image()).src = DOKU_BASE+'lib/plugins/chat/volume3.gif';
(new Image()).src = DOKU_BASE+'lib/plugins/chat/volume4.gif';

addEvent(window, 'load', chatInitialize);

})();