var sl_shownItems = 5;
var sl_firstitem = 0;
var sl_items = 0;
var sl_prefix = "";
var sl_imageid = 0;

function slAnimate(dir) {
	new Effect.Move ($('sliderContent'), { x: 530 * dir, y: 0, mode: 'relative', duration: 0.50, fps: 50,
		queue: {position: 'end', scope: 'sliderscope', limit:4}
	});
}

function slInitSlider(prefix, bootimg) {
	var el = document.getElementById("slider");
	if(el) {
		el = el.getElementsByTagName("li");
		sl_items = el.length;
		sl_firstitem = 0;

		if(sl_items > sl_shownItems) {
			slShowNextButton(true);
		}
		
		showimage(bootimg, prefix);
	}
}

function slNext() {

	var n = sl_firstitem + sl_shownItems;
	if(n > sl_items) {
		return;
	}
	sl_firstitem = n;
	
	slShowPrevButton(true);
	
	if(sl_firstitem + sl_shownItems > sl_items) {
		slShowNextButton(false);
	} 

        slAnimate(-1);
}

function slPrev() {

	var n = sl_firstitem - sl_shownItems;
	if(n < 0) {
		return;  		
	}
	sl_firstitem = n;
	
	if(sl_firstitem - sl_shownItems < 0) {
		slShowPrevButton(false);
	}
	slShowNextButton(true);

        slAnimate(1);	
}

function slShowPrevButton(flag) {
	if(flag) {
		$('sliderPrevButton').style.display="block";
	} else {
		$('sliderPrevButton').style.display="none";
	}
}

function slShowNextButton(flag) {
	if(flag) {
		$('sliderNextButton').style.display="block";
	} else {
		$('sliderNextButton').style.display="none";
	}
}

function showimage(n, prefix) {
	var img = document.createElement('img');
	img.onload=imageComplete;
	sl_prefix=prefix;
	sl_imageid=n;
	img.src = prefix + 'view/' + n + '.jpg';
}

function imageComplete() {

	this.onload=null;
	this.style.display="none";
	
	var viewer = $('imageview');
	viewer.innerHTML="";
	
	var link = document.createElement('a');
	link.href=sl_prefix + "getmax.php?id=" + sl_imageid;
	link.target="_blank";
	
	link.appendChild(this);
	viewer.appendChild(link);
	
	new Effect.Appear(this, { duration: 0.5 });
}