var maxbanner=1;
function Fade(banner,value) {
	prev_banner=banner-1;
	prev_value=100-value;
	if (prev_banner==0) prev_banner=maxbanner;
	document.getElementById("bannerC"+prev_banner).style.opacity=prev_value/100;
	document.getElementById("bannerB"+prev_banner).style.opacity=prev_value/100;
	document.getElementById("bannerA"+prev_banner).style.opacity=prev_value/100;
	document.getElementById("bannerC"+prev_banner).style.filter = 'alpha(opacity=' + prev_value + ')';
	document.getElementById("bannerB"+prev_banner).style.filter = 'alpha(opacity=' + prev_value + ')';
	document.getElementById("bannerA"+prev_banner).style.filter = 'alpha(opacity=' + prev_value + ')';
	document.getElementById("bannerC"+banner).style.opacity = value/100;
	document.getElementById("bannerB"+banner).style.opacity = value/100;
	document.getElementById("bannerA"+banner).style.opacity = value/100;
	document.getElementById("bannerC"+banner).style.filter = 'alpha(opacity=' + value + ')';
	document.getElementById("bannerB"+banner).style.filter = 'alpha(opacity=' + value + ')';
	document.getElementById("bannerA"+banner).style.filter = 'alpha(opacity=' + value + ')';
	if (value==100) {
		document.getElementById("bannerC"+prev_banner).style.zIndex=2;
		document.getElementById("bannerB"+prev_banner).style.zIndex=2;
		document.getElementById("bannerA"+prev_banner).style.zIndex=1;
		document.getElementById("bannerC"+banner).style.zIndex=5;
		document.getElementById("bannerB"+banner).style.zIndex=5;
		document.getElementById("bannerA"+banner).style.zIndex=3;
	}
	value=value+2;
	if (value==150) {
		value=-50;
		banner++;
		if (banner>maxbanner) banner=1;
	}
	setTimeout('Fade('+banner+','+value+')',50);
}

function check_form(){
  var field = document.f1.email;
            var str = field.value;
            if (window.RegExp) {
              var reg1str = "(@.*@)|(\\.\\.)|(@\\.)|(\\.@)|(^\\.)";
              var reg2str = "^.+\\@(\\[?)[a-zA-Z0-9\\-\\.]+\\.([a-zA-Z]{2,3}|[0-9]{1,3})(\\]?)$";
              var reg1 = new RegExp(reg1str);
              var reg2 = new RegExp(reg2str);
              if (!reg1.test(str) && reg2.test(str))
                return true;
              field.focus();
              field.select();
        window.alert('Nieprawidłowy adres EMAIL');
              return false;
            } else {
              if(str.indexOf("@") >= 0)
                return true;
              field.focus();
              field.select();
         window.alert('Nieprawidłowy adres EMAIL');
              return false;
            }
          }
function add_fav(){
window.external.addFavorite('http://www.upr.org.pl/main/index.php','Unia Polityki Realnej-Strona główna');
}