var numPhotos;
var slideFlowSlider;
var slideFlow;
var currentImg;
var preloader;
var fadeInTimeout;
var scrollHandler;
var photos;
var currentEffect;
var slHover;

var SLIDE_TPL = {
	'b_vertical' : false, 'b_watch': true	/* update while dragging */, 'n_controlWidth': 300, 'n_controlHeight': 7,
	'n_sliderWidth': 14, 'n_sliderHeight': 7, 'n_pathLeft' : 0, 'n_pathTop' : 0, 'n_pathLength' : 300-14, 'n_zIndex': 1
}

var SLIDE_INIT = {
	'n_minValue' : 0, 'n_maxValue' : 100, 'n_value' : 0, 'n_step' : 1
}

var SLIDEFLOW_DATA = {
	'imgWidthNormal': 100, 'imgWidthTilted': 75, 'imgHeight': 90, 'slideDistance': 25,
	'onCenterClick': handleSlideClick, 'handleSlideMove': handleSlideMove, 'containerElement': null,
	'pathLeft': 'photos/left', 'pathCenter': 'photos/center', 'pathRight': 'photos/right',
	'transparentImg': 'images/transparent.gif', 'cursorOpenHand': 'images/openhand.cur', 'cursorClosedHand': 'images/closedhand.cur'
}

function handleSlideMove(pos) {
	if (slideFlowSlider)
		slideFlowSlider.f_setValue(pos, false, true /* kein update */);
}

function handleSlideClick(imgNumber) {
	swapPhoto(imgNumber);
}

function handleSlideSeek(pos) {
	slideFlow.disableMoveUpdate();
	slideFlow.glideToPerc(pos);
}

function swapPhoto(photoNumber) {
    /* Preload */
    var imgSrc = 'photos/large/'+ photos.item(photoNumber - 1).getElementsByTagName("src")[0].childNodes[0].nodeValue;
    var wasPreloading = (preloader != undefined);
    preloader = new Image;
    preloader.src = imgSrc;
    currentImg = photoNumber;

    /* Fade out and show new photo */
    if (!wasPreloading) {
		if (currentEffect && currentEffect.state != 'finished')
			currentEffect.cancel();

    	currentEffect = new Effect.Fade($('fadeArea'), { duration:0.4, to: 0.001, afterFinish: fadeIn });
    }
}

function skipPhoto(offset) {
	photoNumber = currentImg + offset;
	if (photoNumber < 1 || photoNumber > numPhotos)
		return;

	swapPhoto(photoNumber);
	slideFlow.glideToSlide(photoNumber);
}

function fadeIn() {
	fadeInTimeout = null;

	if (!preloader)
		return;
	else if (preloader.complete) {
		if (currentEffect && currentEffect.state != 'finished')
			currentEffect.cancel();
	    currentEffect = new Effect.Appear($('fadeArea'), {duration: 0.8, beforeSetup: function(effect) {
		$('photo').src = preloader.src;
		$('title').innerHTML = photos.item(currentImg - 1).getElementsByTagName("title")[0].childNodes[0].nodeValue;
		$('subtitle').innerHTML = photos.item(currentImg - 1).getElementsByTagName("subtitle")[0].childNodes[0].nodeValue;
		preloader = undefined;
	      }});
	} else if (!fadeInTimeout) {
		fadeInTimeout = window.setTimeout("fadeIn()", 100);
	}
}

function handleWheel(delta) {
	if (slideFlow)
		slideFlow.scroll(delta);
}

function handleKeys(evt) {
    evt = (evt) ? evt : ((window.event) ? event : null);
    if (evt) {
    	//debugLog("key " + evt.keyCode);
		switch (evt.keyCode) {
			case 40: /* down */
			case 39: /* right */
				skipPhoto(1);
				return false;
				break;
			case 38: /* up */
			case 37: /* left */
				skipPhoto(-1);
				return false;
				break;
		 }
    }
}

function init() {
	swapPhoto(1);
	slideFlowSlider.f_show();
	document.onkeydown = handleKeys;
	scrollHandler = new ScrollHandler(handleWheel);
	
	/* Preload slider hover */
	slHover = new Image;
	slHover.src = "images/seekslider-hover.gif";	

	/* IE6 hover fix */
	if (window.ieFixHover) {
		 $$('.sliderbutton').each(ieFixHover);
	}
}