var curad = 1;
var maxad = 1;

function fadeIn (object) {	
	var opacity = Number(document.getElementById(object).style.opacity);
	
	if (opacity < 1.0) {
		document.getElementById(object).style.opacity = ""+(opacity+0.1)+"";
		document.getElementById(object).style.filter = "alpha(opacity=" + ( (opacity+0.1) * 100) + ")";
		t = setTimeout ("fadeIn('"+object+"')", 100);
	} else {		
		t = setTimeout ("fadeOut('"+object+"')", 5000);
	}
}

function fadeOut (object) {
	var opacity = Number(document.getElementById(object).style.opacity);
	
	if (opacity > 0.3) {
		document.getElementById(object).style.opacity = ""+(opacity-0.1)+"";
		document.getElementById(object).style.filter = "alpha(opacity=" + ( (opacity-0.1) * 100) + ")";
		t = setTimeout ("fadeOut('"+object+"')", 100);
	} else {
		switchad();
		document.getElementById("ad"+curad).style.opacity = "0.2";
		document.getElementById("ad"+curad).style.filter = "alpha(opacity=20)";
		t = setTimeout ("fadeIn('ad"+curad+"')", 100);
	}
}

function fadeStart (setmaxad) {
    if(document.getElementById("ad"+curad) != null){
        document.getElementById("ad"+curad).style.opacity = "1.0";
        document.getElementById("ad"+curad).style.filter = "alpha(opacity=100)";
        t = setTimeout ("fadeOut('ad"+curad+"')", 5000);

        if (setmaxad != null) {
            maxad = setmaxad;
        } else {
            maxad = 4
        }
    }
}

function switchad (adnum) {
	if (adnum == null) {
		curad ++;
		if (curad > maxad) {
			curad = 1;
		}
	} else {
		curad = adnum;
	}
	
	for (i = 0; i<maxad; i++) {
		if (document.getElementById ("ad"+(i+1)) != null) {
			document.getElementById ("ad"+(i+1)).style.display = "none";
			document.getElementById ("adbut"+(i+1)).className = "adunsel";
		}
	}
	document.getElementById ("ad"+curad).style.display = "block";
	document.getElementById ("adbut"+curad).className = "adsel";
	document.getElementById("ad"+curad).style.opacity = "1.0";
	document.getElementById("ad"+curad).style.filter = "alpha(opacity=100)";
}