//
//	Configuration
//

var ROOT = "/site/";
var fileLoadingImage = ROOT+"images/loading.gif";		
var fileBottomNavCloseImage = ROOT+"images/closelabel.gif";
var borderSize = 10;

funcoes = {
	getWidth: function(element) {
	   	element = lightbox.ob(element);
	   	return element.offsetWidth; 
	},
	setWidth: function(element,w) {
	   	element = lightbox.ob(element);
    	element.style.width = w +"px";
	},
	getHeight: function(element) {
	   	element = lightbox.ob(element);
	   	return element.offsetHeight; 
	},
	setHeight: function(element,h) {
   		element = lightbox.ob(element);
    	element.style.height = h +"px";
	},
	setTop: function(element,t) {
	   	element = lightbox.ob(element);
    	element.style.top = t +"px";
	},
	setSrc: function(element,src) {
    	element = lightbox.ob(element);
    	element.src = src; 
	},
	setHref: function(element,href) {
    	element = lightbox.ob(element);
    	element.href = href; 
	},
	setInnerHTML: function(element,content) {
		element = lightbox.ob(element);
		element.innerHTML = content;
	},
	
	show: function (element) {
		lightbox.ob(element).style.display = 'block';
	},
	
	hide: function (element) {
		lightbox.ob(element).style.display = 'none';
	}
}

lightbox = {
	initialize : function () {
		var anchors = document.getElementsByTagName('a');
		
		for (var i=0; i<anchors.length; i++){
			var anchor = anchors[i];
			
			var relAttribute = String(anchor.getAttribute('rel'));
			
			// use the string.match() method to catch 'lightbox' references in the rel attribute
			if (anchor.getAttribute('href') && (relAttribute.toLowerCase().match('lightbox'))){
				anchor.onclick = function () {lightbox.start(this); return false;}
			}
		}
		
		var objBody = document.getElementsByTagName("body").item(0);
		
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		objOverlay.style.display = 'none';
		objOverlay.onclick = function() { lightbox.end(); return false; }
		objBody.appendChild(objOverlay);
		
		var objLightbox = document.createElement("div");
		objLightbox.setAttribute('id','lightbox');
		objLightbox.style.display = 'none';
		objBody.appendChild(objLightbox);
	
		var objOuterImageContainer = document.createElement("div");
		objOuterImageContainer.setAttribute('id','outerImageContainer');
		objLightbox.appendChild(objOuterImageContainer);

		var objImageContainer = document.createElement("div");
		objImageContainer.setAttribute('id','imageContainer');
		objOuterImageContainer.appendChild(objImageContainer);
	
		var objLightboxImage = document.createElement("img");
		objLightboxImage.setAttribute('id','lightboxImage');
		objImageContainer.appendChild(objLightboxImage);
	
		var objHoverNav = document.createElement("div");
		objHoverNav.setAttribute('id','hoverNav');
		objImageContainer.appendChild(objHoverNav);
	
		var objPrevLink = document.createElement("a");
		objPrevLink.setAttribute('id','prevLink');
		objPrevLink.setAttribute('href','#');
		objHoverNav.appendChild(objPrevLink);
		
		var objNextLink = document.createElement("a");
		objNextLink.setAttribute('id','nextLink');
		objNextLink.setAttribute('href','#');
		objHoverNav.appendChild(objNextLink);
	
		var objLoading = document.createElement("div");
		objLoading.setAttribute('id','loading');
		objImageContainer.appendChild(objLoading);
	
		var objLoadingLink = document.createElement("a");
		objLoadingLink.setAttribute('id','loadingLink');
		objLoadingLink.setAttribute('href','#');
		objLoadingLink.onclick = function() { lightbox.end(); return false; }
		objLoading.appendChild(objLoadingLink);
	
		var objLoadingImage = document.createElement("img");
		objLoadingImage.setAttribute('src', fileLoadingImage);
		objLoadingLink.appendChild(objLoadingImage);

		var objImageDataContainer = document.createElement("div");
		objImageDataContainer.setAttribute('id','imageDataContainer');
		objImageDataContainer.className = 'clearfix';
		objLightbox.appendChild(objImageDataContainer);

		var objImageData = document.createElement("div");
		objImageData.setAttribute('id','imageData');
		objImageDataContainer.appendChild(objImageData);
	
		var objImageDetails = document.createElement("div");
		objImageDetails.setAttribute('id','imageDetails');
		objImageData.appendChild(objImageDetails);
	
		var objCaption = document.createElement("span");
		objCaption.setAttribute('id','caption');
		objImageDetails.appendChild(objCaption);
	
		var objNumberDisplay = document.createElement("span");
		objNumberDisplay.setAttribute('id','numberDisplay');
		objImageDetails.appendChild(objNumberDisplay);
		
		var objBottomNav = document.createElement("div");
		objBottomNav.setAttribute('id','bottomNav');
		objImageData.appendChild(objBottomNav);
	
		var objBottomNavCloseLink = document.createElement("a");
		objBottomNavCloseLink.setAttribute('id','bottomNavClose');
		objBottomNavCloseLink.setAttribute('href','#');
		objBottomNavCloseLink.onclick = function() { lightbox.end(); return false; }
		objBottomNav.appendChild(objBottomNavCloseLink);
	
		var objBottomNavCloseImage = document.createElement("img");
		objBottomNavCloseImage.setAttribute('src', fileBottomNavCloseImage);
		objBottomNavCloseLink.appendChild(objBottomNavCloseImage);
		
	},
	
	ob : function (id) {
		return document.getElementById(id);
	},
	
	end : function () {
		this.ob('lightbox').style.display = 'none';
	},
	
	start : function (imageLink) {
		var arrayPageSize = getPageSize();
		funcoes.setHeight('overlay', arrayPageSize[1]);

		imageArray = [];
		imageNum = 0;
		
		if (!document.getElementsByTagName){ return; }
		var anchors = document.getElementsByTagName('a');

		// if image is NOT part of a set..
		if((imageLink.getAttribute('rel') == 'lightbox')){
			// add single image to imageArray
			imageArray.push(new Array(imageLink.getAttribute('href'), imageLink.getAttribute('title')));			
		} else {
		// if image is part of a set..

			// loop through anchors, find other images in set, and add them to imageArray
			for (var i=0; i<anchors.length; i++){
				var anchor = anchors[i];
				if (anchor.getAttribute('href') && (anchor.getAttribute('rel') == imageLink.getAttribute('rel'))){
					imageArray.push(new Array(anchor.getAttribute('href'), anchor.getAttribute('title')));
				}
			}
			imageArray.removeDuplicates();
			while(imageArray[imageNum][0] != imageLink.getAttribute('href')) { imageNum++;}
		}
		
		
		var arrayPageSize = getPageSize();
		var arrayPageScroll = getPageScroll();
		var lightboxTop = arrayPageScroll[1] + (arrayPageSize[3] / 15);

		funcoes.setTop('lightbox', lightboxTop);
		funcoes.show('lightbox');
		
		this.changeImage(imageNum);
	},
	
	changeImage: function(imageNum) {	
		
		activeImage = imageNum;	// update global var

		// hide elements during transition
		funcoes.show('loading');
		funcoes.hide('lightboxImage');
		funcoes.hide('hoverNav');
		funcoes.hide('prevLink');
		funcoes.hide('nextLink');
		funcoes.hide('imageDataContainer');
		funcoes.hide('numberDisplay');		
		
		imgPreloader = new Image();
		
		// once image is preloaded, resize image container
		imgPreloader.onload=function(){
			funcoes.setSrc('lightboxImage', imageArray[activeImage][0]);
			lightbox.resizeImageContainer(imgPreloader.width, imgPreloader.height);
		}
		imgPreloader.src = imageArray[activeImage][0];
	},
	
	resizeImageContainer: function( imgWidth, imgHeight) {

		// get current height and width
		this.wCur = funcoes.getWidth('outerImageContainer');
		this.hCur = funcoes.getHeight('outerImageContainer');

		// scalars based on change from old to new
		this.xScale = ((imgWidth  + (borderSize * 2)) / this.wCur) * 100;
		this.yScale = ((imgHeight  + (borderSize * 2)) / this.hCur) * 100;

		// calculate size difference between new and old image, and resize if necessary
		wDiff = (this.wCur - borderSize * 2) - imgWidth;
		hDiff = (this.hCur - borderSize * 2) - imgHeight;

		// if new and old image are same size and no scaling transition is necessary, 
		// do a quick pause to prevent image flicker.
		if((hDiff == 0) && (wDiff == 0)){
			if (navigator.appVersion.indexOf("MSIE")!=-1){ pause(250); } else { pause(100);} 
		}

		funcoes.setHeight('prevLink', imgHeight);
		funcoes.setHeight('nextLink', imgHeight);

		funcoes.setWidth('outerImageContainer', imgWidth + (borderSize * 2));
		funcoes.setWidth('imageDataContainer', imgWidth + (borderSize * 2));		
		funcoes.setHeight('outerImageContainer', imgHeight + (borderSize * 2));

		this.showImage();
	},
	
	updateDetails: function() {
	
		funcoes.show('caption');
		funcoes.setInnerHTML( 'caption', imageArray[activeImage][1]);
		
		// if image is part of set display 'Image x of x' 
		if(imageArray.length > 1){
			funcoes.show('numberDisplay');
			funcoes.setInnerHTML( 'numberDisplay', "Imagem " + eval(activeImage + 1) + " de " + imageArray.length);
		}

		lightbox.updateNav();
	},

	updateNav: function() {

		funcoes.show('hoverNav');				

		// if not first image in set, display prev image button
		if(activeImage != 0){
			funcoes.show('prevLink');
			document.getElementById('prevLink').onclick = function() {
				lightbox.changeImage(activeImage - 1); return false;
			}
		}

		// if not last image in set, display next image button
		if(activeImage != (imageArray.length - 1)){
			funcoes.show('nextLink');
			document.getElementById('nextLink').onclick = function() {
				lightbox.changeImage(activeImage + 1); return false;
			}
		}
		
		this.enableKeyboardNav();
	},
	
	enableKeyboardNav: function() {
		document.onkeydown = this.keyboardAction; 
	},

	disableKeyboardNav: function() {
		document.onkeydown = '';
	},
	
	showImage: function(){
		funcoes.hide('loading');
		funcoes.show('lightboxImage');
		funcoes.show('bottomNavClose');
		funcoes.show('imageDataContainer');
		funcoes.show('numberDisplay');	
		/*
		if(imageArray.length>1) {
			funcoes.show('hoverNav');
			funcoes.show('prevLink');
			funcoes.show('nextLink');	
		}
		*/
		lightbox.updateDetails();
		this.preloadNeighborImages();
	},
	
	preloadNeighborImages: function(){

		if((imageArray.length - 1) > activeImage){
			preloadNextImage = new Image();
			preloadNextImage.src = imageArray[activeImage + 1][0];
		}
		if(activeImage > 0){
			preloadPrevImage = new Image();
			preloadPrevImage.src = imageArray[activeImage - 1][0];
		}
	}
}

Array.prototype.removeDuplicates = function () {
	for(i = 1; i < this.length; i++){
		if(this[i][0] == this[i-1][0]){
			this.splice(i,1);
		}
	}
}


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