/**
 * Arnold UI Carousel jQuery Plugin
 * @version 1
 * @author James Childers
 * @copyright (c) 2012 Arnold Media Consulting
 * @requires jQuery 1.7.1
 */

$.fn.carousel = function(options, callback) {

  if($.isFunction(options)) {
    callback = options;
    options = {};
  }

  // combine default options and user provided options
  options = $.extend({}, $.fn.carousel.default_options, options);

  var currentIndex = 0, methods = {

    init: function() {

      // loop through instances
      return this.each(function() {

        // create instance object
        var carousel = {
          parentEl: $(this),
          wrapper : $(this).find(options.wrapperSelectorName),
          items   : $(this).find(options.wrapperSelectorName).find(options.itemSelectorName)
        };

        // set required css
        var maskWidth = 0;
        carousel.items.each(function(i, el) {
          if (i == 0) {
            $(this).addClass('selected')
          }

          maskWidth += ($(this).outerWidth() + 100);
          $(this).css({'width': $(this).width(), 'margin-right': 100});
        });
        carousel.wrapper.css({'position': 'relative', 'width': maskWidth});
        carousel.items.css({'float': 'left'});

        carousel.parentEl.css({'position': 'relative'});
        if(options.showMask) {
          carousel.parentEl.css({'overflow': 'hidden'});
        }

        // move to defualt position
        methods.move(carousel, options.defaultPosition);
        carousel.parentEl.data('is-animating', false);

        // create nav + pagination html
        var html = '';
        if(options.showNav) {
          html += '<div class="amc-carousel-nav"><a href="#" class="amc-carousel-prev">Previous</a><a href="#" class="amc-carousel-next">Next</a></div>';
        }

        if(options.showPagination) {
          html += '<div class="amc-carousel-pagination" style="display: inline-block;">';
          html += '<div class="amc-carousel-pagination-item"><a href="#" class="amc-carousel-prev">Previous</a></div>';
          carousel.items.each(function(i) {
            html += '<div class="amc-carousel-pagination-item" id="amc-carousel-pagination-item-' + (i + 1) + '" data-index="' + i + '"><a href="#">' + (i + 1) + '</a></div>';
          });
          html += '<div class="amc-carousel-pagination-item"><a href="#" class="amc-carousel-next">Next</a></div>';
          html += '</div>';
        }

        // add to dom
        carousel.parentEl.append(html);

        // center pagination
        if(options.centerPagination) {
          var pagWrap = carousel.parentEl.find('.amc-carousel-pagination'),
            pagWidth = pagWrap.width();
          pagWrap.css({
            width: pagWidth,
            position: 'relative',
            marginLeft: '50%',
            left: (pagWidth/2) * -1
          })

        }

        // next btn
        carousel.parentEl.find('.amc-carousel-next').click(function(e) {
          methods.showNext(carousel);
          e.preventDefault();
          e.stopPropagation();
        });

        // prev btn
        carousel.parentEl.find('.amc-carousel-prev').click(function(e) {
          methods.showPrev(carousel);
          e.preventDefault();
          e.stopPropagation();
        });

        // pagination btns
        carousel.parentEl.find('.amc-carousel-pagination .amc-carousel-pagination-item[data-index] a').click( function(e) {

          var newPosition = $(this).parent().data('index'), $this = $(this);
          carousel.parentEl.find('.amc-carousel-pagination .amc-carousel-pagination-item[data-index].selected').removeClass('selected');

          carousel.parentEl.find('.item').removeClass('selected');
          $(carousel.parentEl.find('.item')[$(this).parent().data('index')]).addClass('selected');

          $this.parent().addClass('selected');

          methods.move(carousel, newPosition);
          e.preventDefault();
          e.stopPropagation();

        });

        // set active pagination item
        carousel.parentEl.find('.amc-carousel-pagination div[data-index=' + options.defaultPosition + ']').addClass('selected');


      });

    },

    showNext: function(carousel) {

      var currentWrapPosition = carousel.wrapper.position().left;
      var itemWidth = carousel.wrapper.width() / carousel.items.length;
      var newPosition = Math.abs(currentWrapPosition / itemWidth);
      var newIndex = Math.ceil(newPosition)+1;

      if(newIndex === carousel.items.length) {
        methods.move(carousel, 0, 'next');
      } else {
        methods.move(carousel, newIndex, 'next');
      }

    },

    showPrev: function(carousel) {

      var currentWrapPosition = carousel.wrapper.position().left;
      var itemWidth = carousel.wrapper.width() / carousel.items.length;
      var newPosition = Math.abs(currentWrapPosition / itemWidth);

      var newIndex = Math.ceil((newPosition < carousel.items.length && newPosition > 0) ? newPosition - 1 : carousel.items.length - 1);

      // if in first pos, move to last
      if(currentWrapPosition === 0) {
        methods.move(carousel, carousel.items.length - 1, 'previous');
      } else {
        methods.move(carousel, newIndex, 'previous');
      }

    },

    move: function(carousel, newPosition, direction) {

      if(carousel.parentEl.data('is-animating')) {
        return carousel;
      }

      var currentSelection = carousel.parentEl.find('.amc-carousel-pagination .amc-carousel-pagination-item[data-index].selected');
      var currentItem = carousel.parentEl.find('.item.selected');
      var firstItem = carousel.parentEl.find('.item:first');
      var lastItem = carousel.parentEl.find('.item:last');

      if(direction == 'next') {
        if(!currentSelection.next().find('a.amc-carousel-next').length > 0) {
          currentSelection.next().addClass('selected');
          currentItem.next().addClass('selected');
        } else {
          carousel.parentEl.find('.amc-carousel-pagination .amc-carousel-pagination-item[data-index]').first().addClass('selected');
          firstItem.addClass('selected')
        }
        currentSelection.removeClass('selected');
        currentItem.removeClass('selected');
      }
      if(direction == 'previous') {
        if(!currentSelection.prev().find('a.amc-carousel-prev').length > 0) {
          currentSelection.prev().addClass('selected');
          currentItem.prev().addClass('selected');
        } else {
          carousel.parentEl.find('.amc-carousel-pagination .amc-carousel-pagination-item[data-index]').last().addClass('selected');
          lastItem.addClass('selected')
        }
        currentSelection.removeClass('selected');
        currentItem.removeClass('selected');
      }


      // update pagination


      // get current and new pos
      var itemWidth = carousel.wrapper.width() / carousel.items.length;
      var currentWrapPosition = carousel.wrapper.position().left;
      newPosition = -(newPosition * itemWidth);

      // animate to new position
      carousel.parentEl.data('is-animating', true);

      carousel.wrapper.stop().animate(
        {
          'left': newPosition
        },
        {
          duration: options.animateSpeed,
          complete: function() {
            carousel.parentEl.data('is-animating', false);
          }
        }
      );

    }



  };

  // call init()
  methods.init.apply(this, []);

};


$.fn.carousel.default_options = {
  wrapperSelectorName       : '.carousel-wrapper',
  itemSelectorName          : '.carousel-item',
  paginationWrapSelectorName: '.amc-carousel-pagination',
  paginationItemSelectorName: '.amc-carousel-pagination-item',
  prevButtonSelectorName    : '.amc-carousel-prev',
  nextButtonSelectorName    : '.amc-carousel-next',
  defaultPosition           : 0,
  animateSpeed              : 500,
  showMask                  : true,
  showNav                   : true,
  showPagination            : true,
  centerPagination          : true,
  marginRight               : 100
};