/***********************************************************************
*
*	thumbmenu.js: Functionality for Dynamic Image Menu
*	Copyright 2007-2008 by Rich Fallis, developer@ecommercialpro.com
*	Ask first before using or modifying
*
************************************************************************/

var selected_div='';			// Initialize name of thumb holder div as global
var scroller=0;					// Initialize timer integer as global
var slow=80;					// Interval in ms
var fast=40;					// Interval in ms
var step_size=0;				// Global to step vars
var slow_step=2;				// Distance traveled per function call of list_up()/list_down() at slow rate
var fast_step=12;				// Distance traveled per function call of list_up()/list_down() at fast rate
var div_height=90;				// Height of the divs containing the images
var container_height=445;		// Height of the div or iframe containing this collection

/** Defined on calling page:
var selected					// Item selected
var i							// Increment/Decrement position
var scroll_limit				// Set limit for scrolling left
**/

function set_opacity(obj, opacity) {
	obj.style.opacity = opacity;
	obj.style.filter = 'alpha(opacity=' + opacity*100 + ')';
}

function init(){
	if(i!=0)
		set_opacity(document.getElementById('left'), 1.0);
	if(i==scroll_limit)
		set_opacity(document.getElementById('right'), .5);
	selected_string='image_holder_'.selected;
	div=document.getElementById(selected_string);
}

function show_selection(obj){
	current_img=document.getElementById('thumb_'+selected);
	current_img.style.backgroundColor='#ffffff';
	new_img_string='thumb_' + obj.id.substr(6);
	new_img=document.getElementById(new_img_string);
	new_img.style.backgroundColor='#0099CC';
	selected=obj.id.substr(6);
}


function list_right(){
	if(i<0)	set_opacity(document.getElementById('left'), 1.0);
	if(i>scroll_limit){
		set_opacity(document.getElementById('right'), 1.0);
		i=i-step_size;
		document.getElementById('carrier').style.left=i + 'px';
		}
	else
		set_opacity(document.getElementById('right'), .5);
	}
	
function list_left(){
	if(i>scroll_limit)	set_opacity(document.getElementById('right'), 1.0);
	if(i<0){
		set_opacity(document.getElementById('left'), 1.0);
		i=i+step_size;
		document.getElementById('carrier').style.left=i + 'px';
		}
	else
		set_opacity(document.getElementById('left'), .5);
	}
	
function go_left(rate){
	(rate==slow) ? step_size=slow_step : step_size=fast_step;
	scroller=clearInterval(scroller);
	scroller=setInterval('list_left()', rate);
	}
	
function go_right(rate){
	(rate==slow) ? step_size=slow_step : step_size=fast_step;
	scroller=clearInterval(scroller);
	scroller=setInterval('list_right()', rate);
	}
	
function halt(){
	scroller=clearInterval(scroller);
	}