// Code for big product card

var normalLeft = new Image();
var normalRight = new Image();
var greyLeft = new Image();
var greyRight = new Image();
var productBigImages = new Array();
var productBigImageIdx = 0;

/*
* Collect all product images to array productBigImages
*/
function initProductBigImages() {
  // init arrows images
  normalLeft.src = "/images/arrow_left.gif";
  normalRight.src = "/images/arrow_right.gif";
  greyLeft.src = "/images/arrow_left_diz.gif";
  greyRight.src = "/images/arrow_right_diz.gif";
  // init array with big images
  pdiv = document.getElementById("productBigImages");
  if (pdiv) {
    var k=0;
    for (i=0; i<pdiv.childNodes.length; i++) {
     if ( 1 == pdiv.childNodes[i].nodeType) {
       productBigImages[k] = pdiv.childNodes[i];
       k=k+1;
     }
    }
  } 
}

function showDiv( div ) {
  div.style.visibility="visible";
  div.style.display="block";
}

function hideDiv( div ) {
  div.style.visibility="hidden";
  div.style.display="none";
}

function updateProductImageArrows() {
  if (document.images.picLeftArrow) {
    document.images.picLeftArrow.src = productBigImageIdx>0 ? normalLeft.src : greyLeft.src;
    document.images.picRightArrow.src = (productBigImageIdx<productBigImages.length-1) ? normalRight.src : greyRight.src;
  }
}

function prevProductImage() {
  if (productBigImageIdx > 0) {
    hideDiv( productBigImages[productBigImageIdx--] );
    showDiv( productBigImages[productBigImageIdx] );
    updateProductImageArrows();
  }
}

function nextProductImage() {
  if (productBigImageIdx < productBigImages.length-1) {
    hideDiv( productBigImages[productBigImageIdx++] );
    showDiv( productBigImages[productBigImageIdx] );
    updateProductImageArrows();
  }
}