var image = new Array();

var caption = new Array();

image[0] = '015.JPG'; caption[0]= 'Logs waiting to be sawn';
image[1] = '013.JPG'; caption[1]= 'Saw blade';
image[2] = '007.JPG'; caption[2]= 'Air Drying';
image[3] = '010.JPG'; caption[3]= 'Solar Kilns';
image[4] = '005.JPG'; caption[4]= 'Lumber Shed';
image[5] = '006.JPG'; caption[5]= 'Lumber Shed';

var maxIndex = 5;

function queryString(parameter) { 
  var loc = location.search.substring(1, location.search.length);
  var param_value = false;

  var params = loc.split("&");
  for (i=0; i<params.length;i++) {
      param_name = params[i].substring(0,params[i].indexOf('='));
      if (param_name == parameter) {
          param_value = params[i].substring(params[i].indexOf('=')+1)
      }
  }
  if (param_value) {
      return param_value;
  }
  else {
      return false; //Here determine return if no parameter is found
  }
}

function writePhotoRow() {
    var photoIndex = parseInt(queryString('photo'),10);
    var prev = maxIndex; 
    var next = 0;
    var isrc = image[0];
    var icap = caption[0];

    if (photoIndex < 0 || photoIndex > maxIndex) { photoIndex = 0; }
    if (photoIndex > 0) { prev = photoIndex - 1; }
    if (photoIndex < maxIndex) { next = photoIndex + 1; }

    isrc = image[photoIndex];
    icap = caption[photoIndex];
    
    document.write(
        "<h3><a href='index.html?photo=" + prev + "'> << </a> " +
        icap + " <a href='index.html?photo=" + next + "'> >> </a></h3>\n" +
        "<iframe width='480' height='360' frameborder='0' scrolling='no' " +
        "marginheight='0' marginwidth='10'  src='" + isrc + "'</iframe>\n" 
    );
}