var slide_width = 760; //width in pixels
var slide_transition_time = 1; //time in seconds

$(document).ready(
    function(){

	$("a.slide_control").click(
	    function(event){
		event.preventDefault();

		var slide_id = parseInt($(event.target).attr('alt'));
		var new_margin_left = (-1 * slide_width) * slide_id;
		setSelected(slide_id);

		$("ul.moving_slideshow").animate(
		    {
			marginLeft: new_margin_left+"px"
		    },
		    slide_transition_time * 1000
		);
	    }
	);
});

function setSelected(index){
    $("a.slide_control").each(
	function(i){
	    if ( $(this).attr('alt') == index ){
		$(this).addClass('selected');
	    } else {
		$(this).removeClass('selected');
	    }
	}
    );
}