var loadingImage = 'loading.gif';		

function getPageScroll(){

	var yScroll;

	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScroll = document.documentElement.scrollTop;
	} else if (document.body) {// all other Explorers
		yScroll = document.body.scrollTop;
	}

	arrayPageScroll = new Array('',yScroll) 
	return arrayPageScroll;
}

//
// getPageSize()
// Returns array with page width, height and window width, height
// Core code from - quirksmode.org
// Edit for Firefox by pHaez
//
function getPageSize(){
	
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = document.body.scrollWidth;
		yScroll = window.innerHeight + window.scrollMaxY;
	} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
		xScroll = document.body.scrollWidth;
		yScroll = document.body.scrollHeight;
	} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
		xScroll = document.body.offsetWidth;
		yScroll = document.body.offsetHeight;
	}
	
	var windowWidth, windowHeight;
	if (self.innerHeight) {	// all except Explorer
		windowWidth = self.innerWidth;
		windowHeight = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
		windowWidth = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body) { // other Explorers
		windowWidth = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
	}	
	
	// for small pages with total height less then height of the viewport
	if(yScroll < windowHeight){
		pageHeight = windowHeight;
	} else { 
		pageHeight = yScroll;
	}

	// for small pages with total width less then width of the viewport
	if(xScroll < windowWidth){	
		pageWidth = windowWidth;
	} else {
		pageWidth = xScroll;
	}


	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
}

function pause(numberMillis) {
	var now = new Date();
	var exitTime = now.getTime() + numberMillis;
	while (true) {
		now = new Date();
		if (now.getTime() > exitTime)
			return;
	}
}

function getKey(e){
	if (e == null) { // ie
		keycode = event.keyCode;
	} else { // mozilla
		keycode = e.keyCode;
	}
	if(keycode == 27){ hideLightBoxAndOverlay(); }
}

function listenKey () {	document.onkeypress = getKey; }
	

function faiQualcosa(aUrl, objTextId){
	try {
		var httpObject = new RemoteHandler(aUrl , false).handle();
		scriviPagina(httpObject.responseText, objTextId);
	}
	catch(E){
		scriviPagina("an error has occurred "+E, objTextId);
	}

}
	
function scriviPagina(contenuto, aId){
	new HtmlReplacer(aId).replaceHTML(contenuto);
}

function showLightbox(objLink)
{
	setComboVisibile("hidden");

	var objOverlay = document.getElementById('overlay');
	var objLightbox = document.getElementById('lightbox');
	var objCaption = document.getElementById('lightboxCaption');
	
	var objText = document.getElementById('lightboxText');
	
	var objLoadingImage = document.getElementById('loadingImage');
	var objLightboxDetails = document.getElementById('lightboxDetails');
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();
	
	var lightBoxWidth = 550; 
	
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	objOverlay.style.display = 'block';

	if (objLink.getAttribute('cmdUrl')) {
		faiQualcosa(objLink.getAttribute('cmdUrl'), objText.id);
	} else {
		alert ("hai dimenticato l'href");
	}

	var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3] - 35 - 377) / 2);
	var lightboxLeft = ((arrayPageSize[0] - 20 - lightBoxWidth) / 2);
	
	objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
	objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";
		
	objLightboxDetails.style.width = lightBoxWidth + 'px';
	objLightbox.style.width = lightBoxWidth + 'px';

	if(objLink.getAttribute('title')){
		objCaption.style.display = 'block';
		objCaption.innerHTML = objLink.getAttribute('title');
	} else {
		objCaption.style.display = 'none';
	}
	
	// A small pause between the image loading and displaying is required with IE,
	// this prevents the previous image displaying for a short burst causing flicker.
	if (navigator.appVersion.indexOf("MSIE")!=-1){
		pause(250);
	} 

	if (objLoadingImage) {	objLoadingImage.style.display = 'none'; }
	objLightbox.style.display = 'block';

	arrayPageSize = getPageSize();
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	
	listenKey();
	
}

function hideLightbox()
{
	setComboVisibile("visible");
	objLightbox = document.getElementById('lightbox');
	objLightbox.style.display = 'none';	
	document.onkeypress = '';
}

function hideLightBoxAndOverlay()
{
	hideLightbox();
	objOverlay = document.getElementById('overlay');
	objOverlay.style.display = 'none';	
}

function settaOnClickSugliElementiDiQuestaLista(lista) {

	for (var i=0; i<lista.length; i++){
		var elemento = lista[i];

		if (elemento.getAttribute("cmdUrl") && (elemento.getAttribute("rel") == "lightbox")){
			elemento.onclick = function () {showLightbox(this); return false;}			
		}
	}
	
}

function initLightbox()
{
	
	if (!document.getElementsByTagName){ return; }
	
	var tuttiGliSpan = document.getElementsByTagName("span");
	var tuttiILink = document.getElementsByTagName("a");
	var tutteLeImmagini = document.getElementsByTagName("img");
	var tutteLeTable = document.getElementsByTagName("table");

	settaOnClickSugliElementiDiQuestaLista(tuttiGliSpan);
	settaOnClickSugliElementiDiQuestaLista(tuttiILink);
	settaOnClickSugliElementiDiQuestaLista(tutteLeImmagini);
	settaOnClickSugliElementiDiQuestaLista(tutteLeTable);
	
	var objBody = document.getElementsByTagName("body").item(0);
	
	// create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
	
	var objOverlay = document.createElement("div");
	objOverlay.setAttribute('id','overlay');
	//objOverlay.onclick = function () {hideLightBoxAndOverlay(); return false;}
	objOverlay.style.display = 'none';
	objOverlay.style.position = 'absolute';
	objOverlay.style.top = '0';
	objOverlay.style.left = '0';
	objOverlay.style.zIndex = '90';
 	objOverlay.style.width = '100%';
	objBody.insertBefore(objOverlay, objBody.firstChild);
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// create lightbox div, same note about styles as above
	var objLightbox = document.createElement("div");
	objLightbox.setAttribute('id','lightbox');
	objLightbox.style.display = 'none';
	objLightbox.style.position = 'absolute';
	objLightbox.style.zIndex = '100';	
	
	objBody.insertBefore(objLightbox, objOverlay.nextSibling);
	
	// create details div, a container for the caption and keyboard message
	var objLightboxDetails = document.createElement("div");
	objLightboxDetails.setAttribute('id','lightboxDetails');
	objLightbox.appendChild(objLightboxDetails);

	// create caption
	var objCaption = document.createElement("div");
	objCaption.setAttribute('id','lightboxCaption');
	objCaption.style.font = '18px Arial';
	objCaption.style.color = 'white'; 
	objCaption.style.backgroundColor = '#B5C8CF';
	objCaption.style.padding = '14px';
	objCaption.style.display = 'none';
	objLightboxDetails.appendChild(objCaption);

	// create link
	
	var objLink = document.createElement("div");
	objLink.style.padding = '14px';
	objLightbox.appendChild(objLink);

	var objText = document.createElement("span");
	objText.setAttribute('id', 'lightboxText');
	objText.style.color = 'black';
	objText.style.font = '11px Tahoma';
	
	objLink.appendChild(objText);
	
}

//
// addLoadEvent()
// Adds event to window.onload without overwriting currently assigned onload functions.
// Function found at Simon Willison's weblog - http://simon.incutio.com/
//
function addLoadEvent(func)
{	
	var oldonload = window.onload;
	if (typeof window.onload != 'function'){
    	window.onload = func;
	} else {
		window.onload = function(){
		oldonload();
		func();
		}
	}

}

addLoadEvent(initLightbox);	// run initLightbox onLoad