var prefixPage;
var prefixLink;
var pidList;
var pidStack;
var count;
var pages;
var act;

function libObj( name )
{
	return document.getElementById?document.getElementById(name):document.all?document.body.all[name]:0;
}

function getPageId(index)
{
	return prefixPage+pidStack[index];
}

function setVisible(href,index)
{
    var id = getPageId(index);
  	var elem = libObj(id);
  	if( elem === false )return;
	href.className = 'act';
    elem.style.display = 'block';
    act = index;
}

function setHidden(href,index)
{
    var id = getPageId(index);
  	var elem = libObj(id);
  	if( elem === false )return;
    href.className = 'dummy';
    elem.style.display = 'none';
}

function swapLink(href,index)
{
    if (index == act) return;
    var id = prefixLink+pidStack[act];
    var lastHref = libObj(id);
    if (lastHref === false) return;
    setHidden(lastHref,act);
    setVisible(href,index);
}

function initTeaser()
{
	var num = getRandom(count);
    for (var index in pidStack) {
        var id = prefixLink+pidStack[index];
		var href = libObj(id);
        if( href === false )continue;
        if( index == num) {
           setVisible(href,index);
        }
    }
}

function getRandom( max )
{
	return Math.floor(Math.random()*max );
}