var index = 0;
var counter = 0;
var isPlaying = false;

function Prev() {
	if (isPlaying) { Pause() }
	AdvancePrev();
}

function Next() {
	if (isPlaying) { Pause() }
	AdvanceNext();
}

function AdvancePrev() {
	if (index == 0) {
		index = photos.length - 1;
	} else {
		index = index - 1;
	}
	Advance();
}

function AdvanceNext() {
	if (index == photos.length - 1) {
		index = 0;
	} else {
		index = index + 1;
	}
	Advance();
}

function Rewind() {
	index = 0;
	Advance();
	if (isPlaying) { Pause() }
}

function Advance() {
	document.getElementById('smallViewerImage').style.height = '315px';
	document.getElementById('smallViewerImage').style.cursor = 'pointer';
	if (document.getElementById('smallViewerImage').filters) {
		document.getElementById('smallViewerImage').filters.blendTrans.Apply();
		document.getElementById('smallViewerImage').src = photos[index][0];
		document.getElementById('smallViewerImage').filters.blendTrans.Play();
		document.getElementById('largeViewerImage').filters.blendTrans.Apply();
		document.getElementById('largeViewerImage').src = photos[index][0];
		document.getElementById('largeViewerImage').filters.blendTrans.Play();
	} else {
		document.getElementById('smallViewerImage').src = photos[index][0];
		document.getElementById('largeViewerImage').src = photos[index][0];
	}
	if (document.getElementById('smallCaption')) {
		document.getElementById('smallCaption').innerHTML = photos[index][3];
	}
	if (document.getElementById('largeCaption')) {
		document.getElementById('largeCaption').innerHTML = photos[index][3];
	}
	document.getElementById('cbCount').innerHTML = 'PHOTO ' + (index + 1) + " of " + photos.length;
	if (document.getElementById('overlay')) {
		document.getElementById('overlay').style.display = 'none';
	}
	
	// load next image
	if (document.images) {
		if (index < photos.length - 1) {
			preload_image = new Image();
			preload_image.src = photos[index + 1][0];
		}
	}
}

function Enlarge() {
	document.getElementById('largeViewerBorder').style.display = 'block';
}

function Shrink() {
	document.getElementById('largeViewerBorder').style.display = 'none';
}

function ShowMaximize() {
	document.getElementById('maximize').style.display='block';
}

function HideMaximize() {
	document.getElementById('maximize').style.display='none';					
}

function ShowMinimize() {
	document.getElementById('minimize').style.display='block';
}

function HideMinimize() {
	document.getElementById('minimize').style.display='none';
}

function Play() {
	isPlaying = true;
	document.getElementById('cbPauseBackground').style.display = 'block';
	document.getElementById('cbPause').style.display = 'block';
	PlaySlideshow();
}

function Pause() {
	isPlaying = false;
	clearTimeout(delay);
	document.getElementById('cbPause').style.display = 'none';
	document.getElementById('cbPauseBackground').style.display = 'none';
}

function PlaySlideshow() {
	AdvanceNext();
	if (index > 0) {
		delay = setTimeout("if (isPlaying) { PlaySlideshow() }", 4000);
	} else {
		Pause();
	}
}