/* RANDOM */

function isset(varname)  {
  if(typeof( window[ varname ] ) != "undefined") return true;
  else return false;
}
function firstborn(obj, element)
{
var act=document.getElementById(obj);
var divs=act.getElementsByTagName(element);

var firstborn = Array();
var j=0;
	for (var i = 1; i < divs.length; i++)
	{
		if(divs[i].parentNode.id==act.id)
		{
			firstborn[j]=divs[i].id;
			j++;
		}
	}
return firstborn;
}
/*random*/
// JavaScript Document
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++; 
        } 
    } else if(opacStart < opacEnd) { 
        for(i = opacStart; i <= opacEnd; i++) 
            { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } 
} 

//change the opacity for different browsers 
function startrandom(rand){
if(isset('refres')){clearTimeout(refres);}

var controls=firstborn('controls','div');
for (var a=0;a<controls.length;a++){
	document.getElementById(controls[a]).className='boton';
}
var val=rand<arrayrandom.length?rand++:rand=0;

	document.getElementById('divl'+(val+1)).className='botonon';
	blendimage('blenddiv', 'blendimage', arrayrandom[val].src, 200);
	
	document.getElementById('lpromo').href=vincrandom[val];
	
	refres=setTimeout("startrandom(" + rand + ")",6000);

}
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 shiftOpacity(id, millisec) { 
    //if an element is invisible, make it visible, else make it ivisible 
    if(document.getElementById(id).style.opacity == 0) { 
        opacity(id, 0, 100, millisec); 
    } else { 
        opacity(id, 100, 0, millisec); 
    } 
}

function blendimage(divid, imageid, imagefile, millisec) {
    var speed = Math.round(millisec / 100); 
    var timer = 0; 
     
    //set the current image as background 
    document.getElementById(divid).style.backgroundImage = "url(" + document.getElementById(imageid).src + ")"; 
     
    //make image transparent 
    changeOpac(0, imageid); 
     
    //make new image 
    document.getElementById(imageid).src = imagefile; 

    //fade in image 
    for(i = 0; i <= 100; i++) { 
        setTimeout("changeOpac(" + i + ",'" + imageid + "')",(timer * speed)); 
        timer++; 
    }
}

$(document).ready(function(){
	startrandom(0);
});