function randRange(from, to){
	return Math.round(from + (to-from)*Math.random());
}

function createCookie(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 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 eraseCookie(name) {
	createCookie(name,"",-1);
}

function querySt(ji) {
    hu = window.location.search.substring(1);
    gy = hu.split("&");
    for (i = 0; i < gy.length; i++) {
        ft = gy[i].split("=");
        if (ft[0] == ji) {
            return ft[1];
        }
    }
}

function set_bg_image() {
    var print = querySt('print');

    if (print != 'true') {
        var url = readCookie('bg_image');

        if (!url) {
            var random = randRange(1, 3);
            url = '/Style Library/images/img_fond/fond_' + random + '.jpg';
            createCookie('bg_image', url);
        }

        document.body.style.backgroundImage = "url('" + url + "')";
    }
}