var arrHeader = new Array();
var lastIndex = 0;
var nextIndex = 0;
var changeInterval = 10;
var changeSet = 1

function add2headArr(headid)
{
	arrHeader.push(headid);
}

function start()
{
	isRandom();	
	document.getElementById("bannerRare").style.backgroundImage = "url(fileadmin/templates/images/banner/" + arrHeader[nextIndex] + ".jpg)";
	opacity("bannerFront",100,0,1);
	
	lastIndex = nextIndex;
}

function dofade()
{
	switch(changeSet)
	{
		case 1:
			
			//determine next Item	
			isRandom();	
			document.getElementById("bannerFront").style.backgroundImage = "url(fileadmin/templates/images/banner/" + arrHeader[nextIndex] + ".jpg)";
			opacity("bannerFront",0,100,1600);
			opacity("bannerRare",100,0,1600);
			changeSet = 2;
			
		break;
		
		case 2:
			isRandom();	
			document.getElementById("bannerRare").style.backgroundImage = "url(fileadmin/templates/images/banner/" + arrHeader[nextIndex] + ".jpg)";
			opacity("bannerRare",0,100,1600);
			opacity("bannerFront",100,0,1600);
			changeSet = 1;
						
		break;	
		
		
		
	}
	
	
	
	
	
	lastIndex = nextIndex;
	setTimeout("dofade()",changeInterval*1000); 
}

function opacity(id, opacStart, opacEnd, millisec) { 
    //speed for each frame 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 

    //determine the direction for the blending, if start and end are the same nothing happens 
    if(opacStart > opacEnd) { 
        for(i = opacStart; i >= opacEnd; i--) { 
		   
		    setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
			
			if(i == opacEnd)
			{
				
			}
        } 
    } else if(opacStart < opacEnd) { 
        for(i = opacStart; i <= opacEnd; i++) 
        { 			
			setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
				
        } 
    } 
} 

//change the opacity for different browsers 
function changeOpac(opacity, id) { 
    var object = document.getElementById(id).style; 
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
}


function GetRandom( min, max ) {
	if( min > max ) {
		return( -1 );
	}
	if( min == max ) {
		return( min );
	}
 
        return( min + parseInt( Math.random() * ( max-min+1 ) ) );
}


function isRandom()
{
	nextIndex = GetRandom(0, arrHeader.length - 1);
	
	while(nextIndex == lastIndex)
	{
		nextIndex = GetRandom(0, arrHeader.length - 1);
	}
}