var newsCount = 3;
var news;
var currentNews = -1;
var newsTimer = 0;
var timeDelay = 5000;

window.onload=function() {
	showNext();
	var newsItem = document.getElementById(news[currentNews]);
	
	if (newsItem) {
		newsTimer = setInterval("showNext();", timeDelay);
	
	}	
}

function pauseNews(flag) {

	if (flag) {
	  if (newsTimer > 0) {
	  	clearInterval(newsTimer);
	  	newsTimer = 0;
	  }
	}
	else {
		if (newsTimer == 0) 
			newsTimer = setInterval("showNext();", timeDelay);
	}
}


function showNext() {
	// init news if necessary
	if (!validNews()) {
		initNews();
	}
	else {
		// hide current news
		fadeValue = 0;
		showNews(false);
		currentNews++;
	}
		
	
	if (currentNews >= newsCount) {
		currentNews = 0;
	}
	//currentNews = 2;
	fadeValue = 0;
	showNews(true);	
}

var fadeValue;

function showNews(flag) {
	var newsItem = document.getElementById(news[currentNews]);

	if (newsItem) {
		if (flag) {
  			newsItem.style.opacity = 0;
  			newsItem.style.filter = 'alpha(opacity = ' + 0 + ')';
		}
		
		newsItem.FadeState = (flag) ? -2 : 2;
		fade(news[currentNews]);
		
		if (flag) {
			newsItem.style.display = 'block';
		}
	}
			
}


function initNews() {
	news = new Array();
	
	for (var i=0; i < newsCount; i++) {
		news[i] = "news_" + i;
	}
	
	currentNews = 0;
}

function validNews() {
	if (currentNews >= 0 && currentNews < newsCount)
		return true;
	else
		return false;

}


var TimeToFade = 1000.0;

function fade(eid)
{
  var element = document.getElementById(eid);
  
  if(element == null)
    return;
   
  if(element.FadeState == null)
  {
    if(element.style.opacity == null 
        || element.style.opacity == '' 
        || element.style.opacity == '1')
    {
      element.FadeState = 2;
    }
    else
    {
      element.FadeState = -2;
    }
  }
    
  if(element.FadeState == 1 || element.FadeState == -1)
  {
    element.FadeState = element.FadeState == 1 ? -1 : 1;
    element.FadeTimeLeft = TimeToFade - element.FadeTimeLeft;
  }
  else
  {
    element.FadeState = element.FadeState == 2 ? -1 : 1;
    element.FadeTimeLeft = TimeToFade;
    setTimeout("animateFade(" + new Date().getTime() + ",'" + eid + "')", 33);
  }  
}

function animateFade(lastTick, eid)
{  
  var curTick = new Date().getTime();
  var elapsedTicks = curTick - lastTick;
  
  var element = document.getElementById(eid);
 
  if(element.FadeTimeLeft <= elapsedTicks)
  {
    element.style.opacity = element.FadeState == 1 ? '1' : '0';
    element.style.filter = 'alpha(opacity = ' 
        + (element.FadeState == 1 ? '100' : '0') + ')';
    element.FadeState = element.FadeState == 1 ? 2 : -2;
    return;
  }
 
  element.FadeTimeLeft -= elapsedTicks;
  var newOpVal = element.FadeTimeLeft/TimeToFade;
  if(element.FadeState == 1)
    newOpVal = 1 - newOpVal;

  element.style.opacity = newOpVal;
  element.style.filter = 'alpha(opacity = ' + (newOpVal*100) + ')';
  
  setTimeout("animateFade(" + curTick + ",'" + eid + "')", 33);
}

function toggleNews(idNum) {
  var node = document.getElementById("newsItem" + idNum);
  
  if (node.className == "newsItem")
  	node.className = "fullNewsItem";
  else
  	node.className = "newsItem";
}