/**
* File: headline.js
* 
* Purpose: Set up the animation and rotation for the headlines.
*
*
* History:
*
*
*/

//global variables.
var headline_count;
var headline_interval;
var old_headline = 0;
var current_headline = 0;

/*
* Called when DOM is ready.
*
*/
$(function() {
	headline_count = $("div.headline").size();
	$("div.headline:eq("+current_headline+")").css('top','5px');

	//set the interval that will animate the headline. also pause the headline when user mouse-over the current headline.
	headline_interval = setInterval(headline_rotate,5000); //time in milliseconds
	$('#scrollup').hover(function() {
	 	clearInterval(headline_interval);
	}, function() {
	 	headline_interval = setInterval(headline_rotate,5000); //time in milliseconds
		 headline_rotate();
	});		   
});

/*
* Animate the new headline coming in and animate the previous headline
* leaving.
*
*/
function headline_rotate() {
	current_headline = (old_headline + 1) % headline_count; 
	
	$("div.headline:eq(" + old_headline + ")").animate({top: -100},"slow", function() {
		$(this).css('top','105px');
	});
	
	$("div.headline:eq(" + current_headline + ")").show().animate({top: 5},"slow");  
	old_headline = current_headline;
}