// funciones basicas para manejar cookies

function SetCookie (name, value) {  
	var argv = SetCookie.arguments;  
	var argc = SetCookie.arguments.length;  
	var expires = (argc > 2) ? argv[2] : null;  
	var path = (argc > 3) ? argv[3] : null;  
	var domain = (argc > 4) ? argv[4] : null;  
	var secure = (argc > 5) ? argv[5] : false; 
    expires = new Date(2001, 12, 31); // plus 1 year	    
	document.cookie = name + "=" + escape (value) + 
	((expires == null) ? "" : ("; expires=" + expires.toGMTString())) + 
	((path == null) ? "" : ("; path=" + path)) +  
	((domain == null) ? "" : ("; domain=" + domain)) +    
	((secure == true) ? "; secure" : "");
}

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

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

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