var promo=null; //reference to a div container
var pulseInterval = 4*1000; // frequency of action
var cycleCount=1; // which cycle to change data
var changeCount = 0;  // iterator
var activePromoIndex = 0; // displayed promo
var messages; // array of messages to display

$(document).ready(function(){
	promo = $("#hp-promo p:first");
	if(promo)
	  if(readInfoFromTemplate())
			setInterval("pulsePromo()", pulseInterval);
});

function readInfoFromTemplate(){
  try{
		messages = $("#hp-promo p");
		for(var i=0; i < messages.length; i++)
		  messages[i]=messages.eq(i).clone();
		return (messages.length>1)? true:false;
 	}catch(e){return false;}
}

function pulsePromo(){
	if(++changeCount < cycleCount) // light pulses between promo changes if cycleCount > 1
		promo.fadeTo("slow", 0.7, showFullPromo);
	else{ // changing promo
		changeCount=0;
		changePromo();
	}
};

function showFullPromo(){
		promo.fadeTo("slow", 1);
}

function changePromo(){
		promo.fadeOut('fast', changePromoAndShow);
};

function changePromoAndShow(){
	activePromoIndex = (activePromoIndex+1) % messages.length;
	promo.html(messages[activePromoIndex].html());
	promo.fadeIn('fast');
}