var headers = new Array();
var currentheader = 0;
var nextheader = 0;

function headerinit() {
	cont = document.getElementById('animheader');
	objs = cont.getElementsByTagName('div');
	n = 0;
	for(i=0;i<objs.length;i++) {
		if(objs[i].className == 'header' || objs[i].className == 'headerhidden') {
			headers[n] = objs[i];
			if(objs[i].className == 'header')
				currentheader = n;
			n++;
		}
	}
	
	if((objs.length-1)/2 > 1)
		setTimeout('headerrotate()',6750);
}

function headerrotate() {
	nextheader = currentheader + 1;
	if(nextheader >= headers.length)
		nextheader = 0;

	document.getElementById('header'+nextheader).className = 'headerfade';
	opacity('header'+currentheader,100,0,750);
	setTimeout('headerswap()',800);
	swapnumber(nextheader);
}

function headerswap() {
	document.getElementById('header'+currentheader).className = 'headerhidden';
	document.getElementById('header'+nextheader).className = 'header';
	changeOpac(100,'header'+currentheader);

	currentheader = nextheader;

	setTimeout('headerrotate()',7000);
}

function opacity(id, opacStart, opacEnd, millisec) {
    //speed for each frame
    var speed = Math.round(millisec / 100);
    var timer = 0;

    //determine the direction for the blending, if start and end are the same nothing happens
    if(opacStart > opacEnd) {
        for(i = opacStart; i >= opacEnd; i--) {
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
            timer++;
        }
    } else if(opacStart < opacEnd) {
        for(i = opacStart; i <= opacEnd; i++)
            {
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
            timer++;
        }
    }
}

function changeOpac(opacity, id) {
    var object = document.getElementById(id).style;
    object.opacity = (opacity / 100);
    object.MozOpacity = (opacity / 100);
    object.KhtmlOpacity = (opacity / 100);
    object.filter = "alpha(opacity=" + opacity + ")";
}

function swapnumber(nr) {
	lis = document.getElementById('animtabs').getElementsByTagName('li');
	for(i=0;i<lis.length;i++) {
		lis[i].className = '';
	}
	lis[nr].className = 'active';
} 

setTimeout('headerinit()',500);