var gallery_id        = new Array();
var gallery_direction = new Array();
var gallery_position  = new Array();

function gallery_init(id) {
	i = gallery_id.length;
	gallery_id[i] = id;
	gallery_direction[i] = 0;
	gallery_position[i]  = 0;	
}

function gallery_get_i(id) {
	for (var i = 0; i < gallery_id.length; i++) if (gallery_id[i] == id) return i;
	return -1;
}

function gallery_scroll(id, direction) {
	var i = gallery_get_i(id);
	gallery_direction[i] = parseInt(direction);
}

function gallery_hide_control(id, side) {
	var element;
	element = document.getElementById(id+'-'+side);
	element.className = 'gallery-'+side+' '+'gallery-'+side+'-hidden';
}

function gallery_show_control(id, side) {
	var element;
	element = document.getElementById(id+'-'+side);
	element.className = 'gallery-'+side;
}


function gallery_scroller(id) {
	var i = gallery_get_i(id);
	gallery_position[i] += gallery_direction[i]*4;
	element = document.getElementById(gallery_id[i]);
	if (element != null) {
		if (element.offsetWidth > element.parentNode.offsetWidth) {
			if (gallery_position[i] >= 0) {
				gallery_position[i] = 0;
				gallery_hide_control(id, 'left');
				gallery_direction[i] = 0;
			} else gallery_show_control(id, 'left');
			
			if ((element.offsetWidth + gallery_position[i]) <= element.parentNode.offsetWidth) {
				gallery_position[i] = element.parentNode.offsetWidth - element.offsetWidth;
				gallery_hide_control(id, 'right');
				gallery_direction[i] = 0;
			} else gallery_show_control(id, 'right');
			
			element.style.left = gallery_position[i]+'px';
				
			if (gallery_direction[i] != 0) {	
				setTimeout(function(){gallery_scroller(id)}, 40);
			} else {
				setTimeout(function(){gallery_scroller(id)}, 200);
			}
		} else {
			gallery_hide_control(id, 'left');
			gallery_hide_control(id, 'right');
		}
	}
}

function setNavPos() {
}