var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _get = function get(object, property, receiver) { if (object === null) object = Function.prototype; var desc = Object.getOwnPropertyDescriptor(object, property); if (desc === undefined) { var parent = Object.getPrototypeOf(object); if (parent === null) { return undefined; } else { return get(parent, property, receiver); } } else if ("value" in desc) { return desc.value; } else { var getter = desc.get; if (getter === undefined) { return undefined; } return getter.call(receiver); } };

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

(function ($, anim) {
  'use strict';

  var _defaults = {
    throttle: 100,
    scrollOffset: 200, // offset - 200 allows elements near bottom of page to scroll
    activeClass: 'active',
    getActiveElement: function (id) {
      return 'a[href="#' + id + '"]';
    }
  };

  /**
   * @class
   *
   */

  var ScrollSpy = function (_Component) {
    _inherits(ScrollSpy, _Component);

    /**
     * Construct ScrollSpy instance
     * @constructor
     * @param {Element} el
     * @param {Object} options
     */
    function ScrollSpy(el, options) {
      _classCallCheck(this, ScrollSpy);

      var _this = _possibleConstructorReturn(this, (ScrollSpy.__proto__ || Object.getPrototypeOf(ScrollSpy)).call(this, ScrollSpy, el, options));

      _this.el.M_ScrollSpy = _this;

      /**
       * Options for the modal
       * @member Modal#options
       * @prop {Number} [throttle=100] - Throttle of scroll handler
       * @prop {Number} [scrollOffset=200] - Offset for centering element when scrolled to
       * @prop {String} [activeClass='active'] - Class applied to active elements
       * @prop {Function} [getActiveElement] - Used to find active element
       */
      _this.options = $.extend({}, ScrollSpy.defaults, options);

      // setup
      ScrollSpy._elements.push(_this);
      ScrollSpy._count++;
      ScrollSpy._increment++;
      _this.tickId = -1;
      _this.id = ScrollSpy._increment;
      _this._setupEventHandlers();
      _this._handleWindowScroll();
      return _this;
    }

    _createClass(ScrollSpy, [{
      key: 'destroy',


      /**
       * Teardown component
       */
      value: function destroy() {
        ScrollSpy._elements.splice(ScrollSpy._elements.indexOf(this), 1);
        ScrollSpy._elementsInView.splice(ScrollSpy._elementsInView.indexOf(this), 1);
        ScrollSpy._visibleElements.splice(ScrollSpy._visibleElements.indexOf(this.$el), 1);
        ScrollSpy._count--;
        this._removeEventHandlers();
        $(this.options.getActiveElement(this.$el.attr('id'))).removeClass(this.options.activeClass);
        this.el.M_ScrollSpy = undefined;
      }

      /**
       * Setup Event Handlers
       */

    }, {
      key: '_setupEventHandlers',
      value: function _setupEventHandlers() {
        var throttledResize = M.throttle(this._handleWindowScroll, 200);
        this._handleThrottledResizeBound = throttledResize.bind(this);
        this._handleWindowScrollBound = this._handleWindowScroll.bind(this);
        if (ScrollSpy._count === 1) {
          window.addEventListener('scroll', this._handleWindowScrollBound);
          window.addEventListener('resize', this._handleThrottledResizeBound);
          document.body.addEventListener('click', this._handleTriggerClick);
        }
      }

      /**
       * Remove Event Handlers
       */

    }, {
      key: '_removeEventHandlers',
      value: function _removeEventHandlers() {
        if (ScrollSpy._count === 0) {
          window.removeEventListener('scroll', this._handleWindowScrollBound);
          window.removeEventListener('resize', this._handleThrottledResizeBound);
          document.body.removeEventListener('click', this._handleTriggerClick);
        }
      }

      /**
       * Handle Trigger Click
       * @param {Event} e
       */

    }, {
      key: '_handleTriggerClick',
      value: function _handleTriggerClick(e) {
        var $trigger = $(e.target);
        for (var i = ScrollSpy._elements.length - 1; i >= 0; i--) {
          var scrollspy = ScrollSpy._elements[i];
          if ($trigger.is('a[href="#' + scrollspy.$el.attr('id') + '"]')) {
            e.preventDefault();
            var offset = scrollspy.$el.offset().top + 1;

            anim({
              targets: [document.documentElement, document.body],
              scrollTop: offset - scrollspy.options.scrollOffset,
              duration: 400,
              easing: 'easeOutCubic'
            });
            break;
          }
        }
      }

      /**
       * Handle Window Scroll
       */

    }, {
      key: '_handleWindowScroll',
      value: function _handleWindowScroll() {
        // unique tick id
        ScrollSpy._ticks++;

        // viewport rectangle
        var top = M.getDocumentScrollTop(),
            left = M.getDocumentScrollLeft(),
            right = left + window.innerWidth,
            bottom = top + window.innerHeight;

        // determine which elements are in view
        var intersections = ScrollSpy._findElements(top, right, bottom, left);
        for (var i = 0; i < intersections.length; i++) {
          var scrollspy = intersections[i];
          var lastTick = scrollspy.tickId;
          if (lastTick < 0) {
            // entered into view
            scrollspy._enter();
          }

          // update tick id
          scrollspy.tickId = ScrollSpy._ticks;
        }

        for (var _i = 0; _i < ScrollSpy._elementsInView.length; _i++) {
          var _scrollspy = ScrollSpy._elementsInView[_i];
          var _lastTick = _scrollspy.tickId;
          if (_lastTick >= 0 && _lastTick !== ScrollSpy._ticks) {
            // exited from view
            _scrollspy._exit();
            _scrollspy.tickId = -1;
          }
        }

        // remember elements in view for next tick
        ScrollSpy._elementsInView = intersections;
      }

      /**
       * Find elements that are within the boundary
       * @param {number} top
       * @param {number} right
       * @param {number} bottom
       * @param {number} left
       * @return {Array.<ScrollSpy>}   A collection of elements
       */

    }, {
      key: '_enter',
      value: function _enter() {
        ScrollSpy._visibleElements = ScrollSpy._visibleElements.filter(function (value) {
          return value.height() != 0;
        });

        if (ScrollSpy._visibleElements[0]) {
          $(this.options.getActiveElement(ScrollSpy._visibleElements[0].attr('id'))).removeClass(this.options.activeClass);
          if (ScrollSpy._visibleElements[0][0].M_ScrollSpy && this.id < ScrollSpy._visibleElements[0][0].M_ScrollSpy.id) {
            ScrollSpy._visibleElements.unshift(this.$el);
          } else {
            ScrollSpy._visibleElements.push(this.$el);
          }
        } else {
          ScrollSpy._visibleElements.push(this.$el);
        }

        $(this.options.getActiveElement(ScrollSpy._visibleElements[0].attr('id'))).addClass(this.options.activeClass);
      }
    }, {
      key: '_exit',
      value: function _exit() {
        var _this2 = this;

        ScrollSpy._visibleElements = ScrollSpy._visibleElements.filter(function (value) {
          return value.height() != 0;
        });

        if (ScrollSpy._visibleElements[0]) {
          $(this.options.getActiveElement(ScrollSpy._visibleElements[0].attr('id'))).removeClass(this.options.activeClass);

          ScrollSpy._visibleElements = ScrollSpy._visibleElements.filter(function (el) {
            return el.attr('id') != _this2.$el.attr('id');
          });
          if (ScrollSpy._visibleElements[0]) {
            // Check if empty
            $(this.options.getActiveElement(ScrollSpy._visibleElements[0].attr('id'))).addClass(this.options.activeClass);
          }
        }
      }
    }], [{
      key: 'init',
      value: function init(els, options) {
        return _get(ScrollSpy.__proto__ || Object.getPrototypeOf(ScrollSpy), 'init', this).call(this, this, els, options);
      }

      /**
       * Get Instance
       */

    }, {
      key: 'getInstance',
      value: function getInstance(el) {
        var domElem = !!el.jquery ? el[0] : el;
        return domElem.M_ScrollSpy;
      }
    }, {
      key: '_findElements',
      value: function _findElements(top, right, bottom, left) {
        var hits = [];
        for (var i = 0; i < ScrollSpy._elements.length; i++) {
          var scrollspy = ScrollSpy._elements[i];
          var currTop = top + scrollspy.options.scrollOffset || 200;

          if (scrollspy.$el.height() > 0) {
            var elTop = scrollspy.$el.offset().top,
                elLeft = scrollspy.$el.offset().left,
                elRight = elLeft + scrollspy.$el.width(),
                elBottom = elTop + scrollspy.$el.height();

            var isIntersect = !(elLeft > right || elRight < left || elTop > bottom || elBottom < currTop);

            if (isIntersect) {
              hits.push(scrollspy);
            }
          }
        }
        return hits;
      }
    }, {
      key: 'defaults',
      get: function () {
        return _defaults;
      }
    }]);

    return ScrollSpy;
  }(Component);

  /**
   * @static
   * @memberof ScrollSpy
   * @type {Array.<ScrollSpy>}
   */


  ScrollSpy._elements = [];

  /**
   * @static
   * @memberof ScrollSpy
   * @type {Array.<ScrollSpy>}
   */
  ScrollSpy._elementsInView = [];

  /**
   * @static
   * @memberof ScrollSpy
   * @type {Array.<cash>}
   */
  ScrollSpy._visibleElements = [];

  /**
   * @static
   * @memberof ScrollSpy
   */
  ScrollSpy._count = 0;

  /**
   * @static
   * @memberof ScrollSpy
   */
  ScrollSpy._increment = 0;

  /**
   * @static
   * @memberof ScrollSpy
   */
  ScrollSpy._ticks = 0;

  M.ScrollSpy = ScrollSpy;

  if (M.jQueryLoaded) {
    M.initializeJqueryWrapper(ScrollSpy, 'scrollSpy', 'M_ScrollSpy');
  }
})(cash, M.anime);