var images = new Object();

function setup() { 
  if (!document.getElementsByTagName) return;
  
  divs = document.getElementsByTagName("DIV");
  for (var i = 0; i < divs.length; i ++) {
    if (divs[i].className == "img_rot_container") {
      id = "img_rot_" + i;
      divs[i].id = id;
      images[id] = new Object();

      imgStr = divs[i].getAttribute('images');
      if (!imgStr) continue;
      
      imgArr = imgStr.split(' ');
      images[id]["images"] = imgArr;
      images[id]["curr"] = 0;
      images[id]["total"] = imgArr.length;

      subDivs = divs[i].getElementsByTagName('DIV');
      for (j = 0; j < subDivs.length; j++) {        
        if (subDivs[j].className == "img_rot_controls") {
          subDivs[j].style.display = "block";
        }

        if (subDivs[j].className == "img_rot_prev") {
          subDivs[j].onclick = prev_image;
        }

        if (subDivs[j].className == "img_rot_next") {
          subDivs[j].onclick = next_image;
        }

        if (subDivs[j].className == "img_rot_num") {
          subDivs[j].innerHTML = "1/" + images[id]["total"];
          subDivs[j].id = "img_rot_" + i + "_num";
          images[id]["num_div"] = subDivs[j];
        }
      }

      subImgs = divs[i].getElementsByTagName('IMG');
      for (j = 0; j < subImgs.length; j++) {
        if (subImgs[j].className == "img_rot_image") {
          subImgs[j].id = "img_rot_" + i + "_img" ;
          images[id]["img_tag"] = subImgs[j];
        }
      }
    }
  }
        
  return; 
}
 
function prev_image() { rot_image(this, -1); }
function next_image() { rot_image(this, 1); }
function rot_image(elm, amt) {
  var container = elm.parentNode.parentNode;
  if(!container) return;

  var id = container.id
  var img_id = container.id + "_img";

  if(!images[id]) return;
  if(!images[id]["img_tag"]) return;
  
  images[id]["curr"] += amt;
  if(images[id]["curr"] == images[id]["total"])
    images[id]["curr"] = 0;
  if(images[id]["curr"] < 0)
    images[id]["curr"] = images[id]["total"] - 1;

  images[id]["img_tag"].src = "images/boards/" + images[id]["images"][images[id]["curr"]];

  images[id]["num_div"].innerHTML = (images[id]["curr"] + 1)  + "/" + images[id]["total"]; 
  
  return; 
}