var resultArray;
var setNumber = 1;
var setCount = 0 ;
var setCountMax = 5;
var lastPos = 0;

// Initializes global variables and session state.
function pageLoad()
{
    PageMethods.GetFeaturedImages(OnSucceeded, OnFailed);
}


// Callback function invoked on successful 
// completion of the page method.
function OnSucceeded(result, userContext, methodName) 
{
    resultArray = result;
    setCount = (resultArray.length/3);
    //SwapImage();
    preload();
    
}

// Callback function invoked on failure 
// of the page method.
function OnFailed(error, userContext, methodName) 
{
    if(error !== null) 
    {
        alert(error.get_message());
    }
}

function SwapImage()
{  
try{
    var pos1 = 0;
    var pos2 = 0;
    var pos3 = 0;
    
    if(setNumber === 1)
    {
       lastPos = 0;
       pos1 = 0;
       pos2 = 1;
       pos3 = 2;
    }
    else
    {
       pos1 = lastPos + 0;
       pos2 = lastPos + 1;
       pos3 = lastPos + 2;      
    }
    
    lastPos = pos3 + 1;
    
    var fileName1 = resultArray[pos1].Id + "_thumb_" + resultArray[pos1].FileName;
    var fileName2 = resultArray[pos2].Id + "_thumb_" + resultArray[pos2].FileName;
    var fileName3 = resultArray[pos3].Id + "_thumb_" + resultArray[pos3].FileName;
    
    var img1 = $get('image1');
    var img2 = $get('image2');
    var img3 = $get('image3');
    
    
    img1.src = '/Content/'+ fileName1;
    img2.src = '/Content/'+ fileName2;
    img3.src = '/Content/'+ fileName3;
    }
    catch(e){}
}

function NextSet()
{
    setNumber++;
    if(setNumber > setCount)
    {
        setNumber = 1;
        lastPos = 0;
    }
    
    if(setNumber > setCountMax)
    {
        setNumber = 1;
        lastPos = 0;
    }
    
    //alert(setNumber);
    if(setCount > 1)
    {
        SwapImage();
    }
}

function preload()
{
    for(index = 0; index < resultArray.length; index++)
    {
        var fileName = resultArray[index].Id + "_thumb_" + resultArray[index].FileName;
        var image = new Image();
        image.src = '/Content/' + fileName;        
    }
}

if (typeof(Sys) !== "undefined") Sys.Application.notifyScriptLoaded();