//slideshow
var slideshow_visible_height = 360;
var slideshow_visible_thumb_count = 4;
var slideshow_thumb_height = 90;
var slideshow_position = 0;

var sildeshow_scroller_id = "slideshow_scroller";
var slideshow_display_id = "slideshow_display";
var slideshow_caption_id = "slideshow_caption";

var slideshow_thumb_count = 0;
var slideshow_thumb_top = 0;
var slideshow_container_height = 0;



function slideshow_init (thumb_count) {
	slideshow_thumb_count = thumb_count;
	slideshow_container_height = slideshow_thumb_count*slideshow_thumb_height;
}

function slideshow_swap (img, caption) {
	document.getElementById(slideshow_display_id).src = img;
	document.getElementById(slideshow_caption_id).innerHTML = caption;
}

function slideshow_up () {
	if(slideshow_thumb_top > 0){
		slideshow_thumb_top -= 1;
		slideshow_position += slideshow_thumb_height;
		new Effect.Move (sildeshow_scroller_id,{ x: 0, y: slideshow_position, mode: 'absolute'});		
	}else{
		return false;
	}
}

function slideshow_down () {
	if(slideshow_thumb_top < (slideshow_thumb_count - slideshow_visible_thumb_count)){
		slideshow_thumb_top += 1;
		slideshow_position -= slideshow_thumb_height;
		new Effect.Move (sildeshow_scroller_id,{ x: 0, y: slideshow_position, mode: 'absolute'});		
	}else{
		return false;
	}
}