var mainTimeOut;
var imageDir = "../images/slideshow/";
var fadeOutOpacity = 1;
var ieFadeOutOpacity = 100;
var fadeInOpacity = 0;
var ieFadeInOpacity = 0;
var step = 0.1;
var ieStep = 10;
var currentDiv = 1;
var nextDiv = 2;
var totalImages = 8


function randomImage() {
	
	var randomImg = Math.floor(Math.random() * totalImages);
	
	randomImg += 1;
	
	if(randomImg <= 9) {
		randomImg = '0' + randomImg; 
	}
	
	return randomImg;
	
}

function initSlide() {
	
	var randomImg1 = randomImage();
	var randomImg2 = randomImage();
	
	document.getElementById("image1").src = imageDir + randomImg1 + ".jpg";
	document.getElementById("image2").src = imageDir + randomImg2 + ".jpg";
	
	document.getElementById("image2").style.filter = 'alpha(opacity = 0)'; //Internet Explorer
	document.getElementById("image2").style.opacity = 0; //Other browsers
	
	mainTimeOut = setTimeout(startFade, 3000);
	
}

function startFade() {

	clearTimeout(mainTimeOut);
	
	fadeOutOpacity = 1;
	fadeInOpacity = 0;
	
	//Internet Explorer
	ieFadeOutOpacity = 100;
	ieFadeInOpacity = 0;
	
	fadeIn();
	fadeOut();
}

function fadeOut() {
	
	var element = document.getElementById('image' + currentDiv);
	
	fadeOutOpacity = fadeOutOpacity -= step;
	ieFadeOutOpacity = ieFadeOutOpacity -= ieStep;
	
	element.style.opacity = fadeOutOpacity;
	element.style.filter = 'alpha(opacity = ' + ieFadeOutOpacity + ')';
	
	if(fadeOutOpacity <= 0.0) {
		clearTimeout(fadeOutTimer);
		
		if(currentDiv == 1) {
			currentDiv = 2;
			var randomImg = randomImage();
			document.getElementById("image1").src = imageDir + randomImg + ".jpg";
		} else {
			currentDiv = 1;
			var randomImg = randomImage();
			document.getElementById("image2").src = imageDir + randomImg + ".jpg";
		}
		
	} else {
		fadeOutTimer = setTimeout(fadeOut, 100);
	}
	
}

function fadeIn() {
	
	var element = document.getElementById('image' + nextDiv);
	
	fadeInOpacity = fadeInOpacity += step;
	ieFadeInOpacity = ieFadeInOpacity += ieStep;
	
	element.style.opacity = fadeInOpacity;
	element.style.filter = 'alpha(opacity = ' + ieFadeInOpacity + ')';
	
	if(fadeInOpacity >= 1) {
		clearTimeout(fadeInTimer);
		
		if(nextDiv == 1) {
			nextDiv = 2;
		} else {
			nextDiv = 1;
		}

		mainTimeOut = setTimeout(startFade, 3000);
		
	} else {
		fadeInTimer = setTimeout(fadeIn, 100);
	}
	
}