/* See http://web-graphics.com/mtarchive/001659.php for more details */
function backToTop() {
    var x1 = x2 = x3 = 0;
    var y1 = y2 = y3 = 0;

    if (document.documentElement) {
        x1 = document.documentElement.scrollLeft || 0;
        y1 = document.documentElement.scrollTop || 0;
    }

    if (document.body) {
        x2 = document.body.scrollLeft || 0;
        y2 = document.body.scrollTop || 0;
    }

    x3 = window.scrollX || 0;
    y3 = window.scrollY || 0;

    var x = Math.max(x1, Math.max(x2, x3));
    var y = Math.max(y1, Math.max(y2, y3));

    window.scrollTo(Math.floor(x / 2), Math.floor(y / 2));

    if (x > 0 || y > 0) {
        window.setTimeout("backToTop()", 30);
    }
}

var lastSize;
function changeTextSize(size) {
  if (lastSize == undefined) lastSize = 100;
  Element.removeClassName('resize' + lastSize, 'active');
  Element.addClassName('resize' + size, 'active');
  Element.setStyle('wrapper', {fontSize: size+'%'});
  lastSize = size;
}

function toggleClass(element, firstClass, secondClass) {
  var removeClass = (Element.hasClassName(element, firstClass) ? firstClass : secondClass)
  var addClass = (Element.hasClassName(element, firstClass) ? secondClass : firstClass)
    
  Element.removeClassName(element, removeClass);
  Element.addClassName(element, addClass);
}

var activeTab;
function init() {
  var tabs = $$('ul#tabs li a');
  tabs.each(function(tab) {
    if (Element.hasClassName(tab.parentElement, 'active')) { activeTab = tab; }
    tab.onclick = function() {
      Element.removeClassName(activeTab.parentElement, 'active');
      Element.addClassName(this.parentElement, 'active')
      Element.hide($A(activeTab.href.split('/')).last());
      Element.show($A(this.href.split('/')).last());
      
      activeTab = this;
      return false;
    }
  })
}
Event.observe(window, 'load', init);