// JavaScript Document
// AED Javascript files
// idea Design, Washington DC
// Young Whang & Madeleine England, programmers


	var winNo=0;
	function popup(url) {

	var width  = 600;
	var height = 800;
	var left   = (screen.width  - width)/2;
	var top    = (screen.height - height)/2;
	var params = 'width='+width+', height='+height;

	params += ', top='+top+', left='+left;
	params += ', directories=no';
	params += ', location=no';
	params += ', menubar=no';
	params += ', resizable=no';
	params += ', scrollbars=no';
	params += ', status=no';
	params += ', toolbar=no';
	
	newwin=window.open(url,'window' + winNo, params);
	if (window.focus) {newwin.focus()}
	winNo++;return false;

	}

function setPage() {

	var query = window.location.search;

	if (query.substring(0,1) == '?') {
		column = query.slice(4);
		query = query.substring(1,4);
		}

	number = parseInt(query,10);

	parseXML(column,number);

	}

function loadXMLdoc(col) {

	column = col + '.xml';
	var xmlDoc;

	if (window.XMLHttpRequest) {

		xmlDoc=new window.XMLHttpRequest();
		xmlDoc.open("GET",column,false);
		xmlDoc.send("");
		return xmlDoc.responseXML;

		}

// IE 5 and IE 6

	else {

		xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
		xmlDoc.async=false;
		xmlDoc.load(column);
		return xmlDoc;

		}

/*	alert("Error loading document");
	return null;
*/
	}

var primeImage = [];
var imgCaption = [];
var resources = [];
var noofImages = 0;

function parseXML(column,number) {

/*	try //Internet Explorer
		{
		xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
		}
		catch(e)
	  		{
			try //Firefox, Mozilla, Opera, etc.
				{
				xmlDoc=document.implementation.createDocument("","",null);
				}
				catch(e)
					{
					alert(e.message);
					return;
					}
			}

	xmlDoc.async=false;
	xmlDoc.load(column +'.xml');

*/
	var xmlDoc = loadXMLdoc(column);
	var topic = xmlDoc.getElementsByTagName('topic')[number];

	document.getElementById('heading').innerHTML = topic.getElementsByTagName('heading')[0].childNodes[0].nodeValue;

	noofImages = topic.getElementsByTagName('image').length;

	for (i=0; i<noofImages; i++) {

		primeImage[i] = new Image();
		primeImage[i].src = topic.getElementsByTagName('image')[i].childNodes[0].nodeValue;

		if (topic.getElementsByTagName('caption')[i] && topic.getElementsByTagName('caption')[i].childNodes[0].nodeValue != 0) {

			imgCaption[i] =  topic.getElementsByTagName('caption')[i].childNodes[0].nodeValue;

			} else {

			imgCaption[i] = '&nbsp;';

			}

		if (topic.getElementsByTagName('resource' + (i+1))[0]) {

			var noofRes = topic.getElementsByTagName('resource' + (i+1)).length;
			var resTemp = '';
				
			for (j=0; j<noofRes; j++) {

				testLink = topic.getElementsByTagName('resLink' + (i+1))[j].childNodes[0].nodeValue;

				if (testLink != 0) {

					hLink = topic.getElementsByTagName('resLink' + (i+1))[j].childNodes[0].nodeValue;
					resTemp += "<a href='" + hLink + "' target='" + "blank'>" + topic.getElementsByTagName('resource' + (i+1))[j].childNodes[0].nodeValue + '</a><br /><br />';

					} else {

					resTemp += "<span>" + topic.getElementsByTagName('resource' + (i+1))[j].childNodes[0].nodeValue + '</span><br /><br />';

					}
			
				}
				
			resources[i] = resTemp;
				
			} else {
				
			resources[i] = 0;
			}
		}
	}

var imgNo = 0;
var t = 0;

function chooseImage(direction) {

	imgNo += direction;

	if (imgNo >= noofImages) {
		imgNo = 0;
		}

	if (imgNo < 0) {
		imgNo = noofImages-1;
		}

	setImage(imgNo);
	}

function setImage(n) {

	if (noofImages == 1) {

		document.getElementById('prevButton').style.visibility = 'hidden';
		document.getElementById('nextButton').style.visibility = 'hidden';
		document.getElementById('imageHolder').style.visibility = 'visible';
		document.getElementById('primeImg').src = primeImage[n].src;
		document.getElementById('caption').innerHTML = imgCaption[n];

		if (resources[n] != 0) {

			document.getElementById('resLinks').innerHTML = resources[n];
			document.getElementById('resources').style.visibility = 'visible';

			} else {
			
			document.getElementById('resources').style.visibility = 'hidden';

			}

		t = 0;
		fadeIn();

		} else {

	if (noofImages > 1) {

		document.getElementById('prevButton').style.visibility = 'visible';
		document.getElementById('nextButton').style.visibility = 'visible';
		document.getElementById('imageHolder').style.visibility = 'visible';
		document.getElementById('primeImg').src = primeImage[n].src;
		document.getElementById('caption').innerHTML = imgCaption[n];

		if (resources[n] != 0) {

			document.getElementById('resLinks').innerHTML = resources[n];
			document.getElementById('resources').style.visibility = 'visible';

			} else {
			
			document.getElementById('resources').style.visibility = 'hidden';

			}

		t = 0;
		fadeIn();

		} else {

			document.getElementById('imageHolder').style.visibility = 'hidden';

			}
		}

	}

function fadeIn() {

	if (t == 21) {

		clearTimeout(fadeInT);
		t = 0;

		} else {

		document.getElementById('primeImg').style.opacity = 0.05*t;
		document.getElementById('primeImg').style.filter = 'alpha(opacity=' + 5*t +')';
		t++;
		fadeInT = setTimeout('fadeIn()',80/t);

		}

	}

function fadeOut(direction) {

	choice = direction;

	if (t == 21) {

		clearTimeout(fadeOutT);
		t = 0;
		chooseImage(choice);

		} else {

		document.getElementById('primeImg').style.opacity = 1 - 0.05*t;
		document.getElementById('primeImg').style.filter = 'alpha(opacity=' + (100 - 5*t) +')';
		t++;
		fadeOutT = setTimeout('fadeOut(choice)',80/t);

		}

	}