$(document).ready(function(){
  var currentPosition = 0;
  var slideWidth = 1003;
  var slides = $('.slide');
  var numberOfSlides = slides.length;

  // Remove scrollbar in JS
  $('#slidesContainer').css('overflow', 'hidden');

  // Wrap all .slides with #slideInner div
  slides
  .wrapAll('<div id="slideInner"></div>')
  // Float left to display horizontally, readjust .slides width
  .css({
    'float' : 'left',
    'width' : slideWidth
  });

  // Set #slideInner width equal to total width of all slides
  $('#slideInner').css('width', slideWidth * numberOfSlides);

  // Insert left and right arrow controls in the DOM
  $('#slideshow')
    .prepend('<div class="control" id="leftControl">Move left</div>')
    .append('<div class="control" id="rightControl">Move right</div>');
    
  for (var i = 0; i < numberOfSlides; i++) {
    $('#slideshow_idx')
    .append('<span id="'+i+'" class="slideshow_idx_item"></span>');
 }
 
    
  // Hide left arrow control on first load
  manageControls(currentPosition);

  // Create event listeners for .controls clicks
  $('.control')
    .bind('click', function(){
    // Determine new position
      currentPosition = ($(this).attr('id')=='rightControl')
    ? currentPosition+1 : currentPosition-1;

      // Hide / show controls
      manageControls(currentPosition);
      // Move slideInner using margin-left
      $('#slideInner').animate({
        'marginLeft' : slideWidth*(-currentPosition)
      });
    });

  // manageControls: Hides and shows controls depending on currentPosition
  function manageControls(position){
    
    //console.log(position);
     $('#slideshow_idx span').attr('class', 'slideshow_idx_item');
     $('#slideshow_idx span#'+position).attr('class', 'slideshow_idx_item_active');
    
    // Hide left arrow if position is first slide
    if(position==0){ $('#leftControl').hide() }
    else{ $('#leftControl').show() }
    // Hide right arrow if position is last slide
    if(position==numberOfSlides-1){ $('#rightControl').hide() }
    else{ $('#rightControl').show() }
    }
  })