function writeCookie(name,value) {
	var argv=writeCookie.arguments;
	var argc=writeCookie.arguments.length;
	var path=(argc>2)?argv[2]:null;
	var domain=(argc>3)?argv[3]:null;
	var expires=(argc>4)?argv[4]:null;
	var secure=(argc>5)?argv[5]:false;
	
	document.cookie=name+"="+escape(value)+
	((expires == null) ? "" : ("; expires=" +expires.toGMTString()))
	+
	((path == null) ? "" : ("; path=" +path))
	+
	((domain == null) ? "" : ("; domain=" +domain()))
	+
	((secure == true) ? "; secure" :"");
}

function readCookie(name) {
	var arg=name +"=";
	var alen=arg.length;
	var clen=document.cookie.length;
	var i=0;
	var notSet=0;
	while (i<clen) {
	var j=i+alen;
	if (document.cookie.substring(i,j)==arg)
		return readCookieVal(j);
	i=document.cookie.indexOf(" ",i)+1;
	if (i==0) break;
	}
	notSet = 1;
	return notSet;
}

function readCookieVal(offset) {
	var endstr=document.cookie.indexOf(";",offset);
	if (endstr==-1)
		endstr=document.cookie.length;
		return unescape (document.cookie.substring(offset,endstr));
}

function deleteCookie(name) {
	var exp=new Date();
	exp.setTime(exp.getTime()-1);
	var cval=readCookie(name);
	document.cookie=name+"="+cval+"; expires="+exp.toGMTString();
}

function overwriteCookie(name,cond,val1,val2){
	if ( eval(cond) ) {
		writeCookie(name,val1,'/');
	} else {
		writeCookie(name,val2,'/');
	}
}

function manageCookie(name,f1,f2){
	if(readCookie(name) == 1){
		writeCookie(name,'opened','/'); 
	} else {
		if( readCookie(name) == "opened" ){
			eval(f1);
		} else {
			eval(f2);
		}
	}
}

function initCookie() {
	manageCookie("extra-contents","showExtraColumn()","hideExtraColumn()");
}
//
// addLoadEvent()
// Adds event to window.onload without overwriting currently assigned onload functions.
// Function found at Simon Willison's weblog - http://simon.incutio.com/
//
function addLoadEvent(func)
{	
	var oldonload = window.onload;
	if (typeof window.onload != 'function'){
    	window.onload = func;
	} else {
		window.onload = function(){
		oldonload();
		func();
		}
	}

}

addLoadEvent(initCookie);

window.onunload = function () { 	
	overwriteCookie('extra-contents',"document.getElementById('extra-contents').style.display=='none'",'closed','opened');							
}