/*
 =====================================
|--------Author By BlackSoul---------|
|------------2006.04.27--------------|
|--------BlackSoulylk@gmail.com------|
|------------QQ:9136194--------------|
|------http://blacksoul.cnblogs.cn---|
======================================
*/

//定义全局量
var pageOpen = new Date();	                            	      //进入页面的时间
var GUID = Math.round(Math.random()*2365489623);    		  //用户唯一随机数
var uexp = pageOpen.getTime() + ( 1000 * 60 * 60 * 24 * 30 ); //设置cookie过期时间 既回访用户的限定
var rtu = "false";                                            //指示用户是否回访用户

//-----------------------获得当前地址-----------------------------
function getHref()
{
	return document.location.href;
}

//-----------------------cookie操作开始-----------------------------------------------------------------------------------------------------------------

function setCookie(name, value)
//设定Cookie值
{
	var expdate = new Date();
	var argv = setCookie.arguments;
	var argc = setCookie.arguments.length;
	var expires = 15768000;
	var path = (argc > 3) ? argv[3] : null;
	var domain = (argc > 4) ? argv[4] : null;
	var secure = (argc > 5) ? argv[5] : false;

	if(expires!=null) 
	{
	//设置过期时间24小时
		expdate.setTime(uexp);
	    document.cookie = name + "=" + escape (value) +((expires == null) ? "" : ("; expires="+ expdate.toGMTString()))
		    + ((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain))
		    + ((secure == true) ? "; secure=" : "");
   }
}

function delCookie(name)
//删除Cookie
{
	var exp = new Date();
	exp.setTime (exp.getTime() - 1);
	var cval = getCookie (name);
	document.cookie = name + "=" + cval + "; expires="+ exp.toGMTString();
}


//获得Cookie的值
function getCookie(fname)
{
    var name,value;
    var cookies = new Object();
    var beginning,middle,end;

    beginning = 0;
    while(beginning < document.cookie.length)
    {
        middle = document.cookie.indexOf("=",beginning);
        end = document.cookie.indexOf(";",beginning);

        if(end == -1)
        {
            end = document.cookie.length;
        }
        if((middle > end) || (middle == -1))
        {
            name = document.cookie.substring(beginning,end);
            value = "";
        }
        else
        {
            name = document.cookie.substring(beginning,middle);
            value = document.cookie.substring(middle+1,end);
        }
        if(name == fname)
        {
            return unescape(value);
        }
        beginning = end + 2;
    }
}

//-----获取GUID的cookie是否存在获得---------------------------------------------------
function getCookieValue()
{
	var guid = getCookie("GUID");
	if(guid != null)
	{
	    return guid;
	}
	else
	{
	    return "noCookie";
	}
}

function isReturn()
{
    //如果没有cookie,则为新的用户,设置初始cookie,用户GUID,初次到访时间.上次到访时间为本次

    if(getCookieValue() == "noCookie")
    {
        setCookie("GUID",GUID);
        setCookie("lastTime",pageOpen.getTime());
        setCookie("firstTime",pageOpen.getTime());
        return GUID;
	}
	else
	{
		//若首次进入时间与当前时间比较超多一个月,则为新用户,针对回访用户
        if((getCookie("firstTime") + 1000*60*60*24*30) < pageOpen.getTime())
        {
            setCookie("GUID",GUID);
            setCookie("lastTime",pageOpen.getTime());
            setCookie("firstTime",pageOpen.getTime());
            return GUID;
        }
        //若首次访问时间小于一个月,大于一天,设为回访用户
        if((getCookie("lastTime") + 1000*60*60*24) > pageOpen.getTime())
        {
            setCookie("lastTime",pageOpen.getTime());
            return getCookieValue();
        }        
        return getCookieValue();
	}
}