function IAGCookie_createCookieDays(name,value,days) {
	if (days) {
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function IAGCookie_createCookieMinutes(name,value,minutes) {
	if (minutes) {
		var date = new Date();
		date.setTime(date.getTime()+(minutes*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function IAGCookie_readCookie(name) {
	var nameEQ = name + "=";
	var ca = document.cookie.split(';');
	for(var i=0;i < ca.length;i++) {
		var c = ca[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
	}
	return null;
}

function IAGCookie_deleteCookie(name) {
	this.createCookie(name,"",-1);
}
	

function IAGCookie_randomKey(length){
	chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
	pass = "";
	for(x=0;x<length;x++)
	{
		i = Math.floor(Math.random() * 62);
		pass += chars.charAt(i);
	}
	return pass;
}

function IAGCookie_randomDateKey(length){
	var currentTime = new Date()
	var	month = padLeftZero(currentTime.getMonth()+1);
	var	day = padLeftZero(currentTime.getDate());
	var year = (''+currentTime.getFullYear()).substring(2,4);
	
	return year + month + day +"_" + IAGCookie_randomKey(length);
}

function padLeftZero(input) {
	var str = input + "";
	if (str.length < 2) {
		str = "0" + str;
	}
	return str;
}	
	
function IAGCookie_getSessionID(){
	return IAGCookie_readCookie("IAG");     
}

function IAGCookie_setSessionCookie(){
	if(null == this.readCookie("IAG")){
		if(this.test) alert("SessionCookie: NULL");
		//this.createCookie("IAG",this.randomDateKey(10));//expire on window close
		this.createCookieMinutes("IAG",this.randomDateKey(this.sessionKeyLength ),this.sessionTimeout);
	}else{
		if(this.test) alert("SessionCookie: set");
		//cookie may expire soon. resave to create a permanent cookie keept for a maximum of a year
		var key = this.getSessionID();		
		this.createCookieMinutes("IAG",key, this.sessionTimeout );
	} 

}

function IAGCookieClass() {
	this.timer =  4 * (60*1000); //10 * 60 * 1000;//milliseconds use 1 * (60 * 1000) for 1 minute
	this.sessionTimeout = 30; //minutes
	this.sessionKeyLength = 8; //30; //length of the session key (int)
	this.test = false; //true or false

    this.createCookieDays = IAGCookie_createCookieDays;
    this.createCookieMinutes = IAGCookie_createCookieMinutes;
    this.createCookie = IAGCookie_createCookieDays;
    this.readCookie = IAGCookie_readCookie;
    this.deleteCookie = IAGCookie_deleteCookie;
    this.randomKey = IAGCookie_randomKey;
    this.randomDateKey = IAGCookie_randomDateKey;
    this.setSessionCookie = IAGCookie_setSessionCookie;    
    this.getSessionID = IAGCookie_getSessionID;    
	if(this.test) alert("IAGCookieClass create object");
	
}


var IAGCookie;
function IAGCookie_setSessionCookieTimer(){	
	if (IAGCookie == null){
		IAGCookie = new IAGCookieClass();
	}
	IAGCookie.setSessionCookie();
	setTimeout ( "IAGCookie_setSessionCookieTimer();", IAGCookie.timer );
	if(IAGCookie.test)alert("ID:" + IAGCookie.getSessionID());	
}
IAGCookie_setSessionCookieTimer();