var images = new Array( 'images/black.gif',
			'images/waterski.jpg',
			'images/black.gif',
			'images/library.jpg',
			'images/black.gif',
			'images/sas.jpg');
var image_link =new Array('portfolio.php?pagename=sas','portfolio.php?pagename=waterski', 'portfolio.php?pagename=waterski', 'portfolio.php?pagename=library', 'portfolio.php?pagename=library', 'portfolio.php?pagename=sas');
var nextImage = 1;
var imageWidth = 550;
var imageHeight = 220;
var imageTimeout = 0;


function setOpacity(el, opacity) {

	//  Which opacity method does this browser support?

	opacity /= 100;

	el.style.opacity = opacity;
	el.style.MozOpacity = opacity;
	el.style.filter = "alpha(opacity=" + (opacity*100) + ")";
	
	el.firstChild.style.opacity = opacity;
	el.firstChild.style.MozOpacity = opacity;
	el.firstChild.style.filter = "alpha(opacity=" + (opacity*100) + ")";

}

function fadeImage(el, currentOpacity) {
	if( nextImage%2 == 0){
		imageTimeout=3000;
	}

	else {
		imageTimeout=500;
	}
		currentOpacity +=2;
	
	if (currentOpacity > 100) {
		setOpacity(el, 100);
		var prevEl = el.previousSibling ? el.previousSibling : el.parentNode.lastChild;
		prevEl.style.visibility = 'hidden';
		el.style.zIndex = 1;
		window.setTimeout(startFading, imageTimeout);
	}
	else {
		setOpacity(el, currentOpacity);
		window.setTimeout(function() { fadeImage(el, currentOpacity); }, 50);
	}

}


function startFading() {
	
	var el = document.getElementById('fading_image_container').childNodes[nextImage];

	el.style.visibility = 'visible';
	el.style.zIndex = 2;
	setOpacity(el, 0);
	fadeImage(el,0);

	nextImage = (nextImage < images.length-1) ? nextImage + 1 : 0;

}


function pageLoad() {

	var el = document.getElementById('fading_image_container');
	while (el.firstChild) { el.removeChild(el.firstChild); }	
	
	for(var i=0; i<images.length; i++) {
		var t = document.createElement('img');
		t.setAttribute('src',images[i]);
		t.setAttribute('width',imageWidth);
		t.setAttribute('height',imageHeight);
		t.style.position = 'absolute';
		//t.style.visibility = 'hidden';
		t.style.cursor= 'pointer';
		var a = document.createElement('a');
		a.setAttribute('href', image_link[i]);
		a.setAttribute('id', 'link'+i);
		a.style.visibility = 'hidden';
		el.appendChild(a);
		var b = document.getElementById('link'+i);
		b.appendChild(t);
	}

	el.firstChild.style.visibility = 'visible';

	window.setTimeout(startFading, imageTimeout);

}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}

addLoadEvent(pageLoad);