// JavaScript Document
var setaVolta = ".seta_volta";
var setaVai = ".seta_vai";
var divMain = ".foto_portfolio";

var photoWidth = 729;
var pos = 1;
var imagesArr = [];
var animationActive = false;

function initApp() {
	imagesArr = loadArr();
	$(setaVai + " a").bind("click",next);
	$(setaVolta + " a img").animate({"opacity":"0.4"});

	$(divMain).css("width",imagesArr.length * photoWidth);
}

function next() {
	if (!animationActive) {
		if (pos < imagesArr.length) {
			var leftPreValue = $(divMain).css("left").replace("px","");
			var leftValue = (Number(leftPreValue) - photoWidth) + "px";	
		
			$(divMain).animate({"left":leftValue},300,"easeout",animeOver);
			animationActive = true;
			pos = pos + 1;
		}
	}	
}

function back() {
	if (!animationActive) {
		if (pos > 1) {
			var leftPreValue = $(divMain).css("left").replace("px","");
			var leftValue = (Number(leftPreValue) + photoWidth) + "px";	
		
			$(divMain).animate({"left":leftValue},300,"easeout",animeOver);
			animationActive = true;
			pos = pos - 1;
		}
	}
}

function animeOver() {
	animationActive = false;
	if (pos > 1) {
		$(setaVolta + " a").bind("click",back);
		$(setaVolta + " a img").animate({"opacity":"1"});
	}
	
	if (pos == imagesArr.length) {
		$(setaVai + " a img").animate({"opacity":"0.4"});		
	}
	
	if (pos > 1 && pos < imagesArr.length) {
		$(setaVolta + " a").bind("click",back);
		$(setaVolta + " a img").animate({"opacity":"1"});
		$(setaVai + " a img").animate({"opacity":"1"});		
	}
	
	if (pos == 1) {
		$(setaVolta + " a img").animate({"opacity":"0.4"});
		if (imagesArr.length > 1) {
			$(setaVai + " a img").animate({"opacity":"1"});				
		}
	}
}

function loadArr() {
	var elements = $(divMain + " span").get();	
	return elements;
}
$(document).ready(function() {
	initApp();
});