'use strict';

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; }; }();

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

!function ($) {

  /**
   * Sticky module.
   * @module foundation.sticky
   * @requires foundation.util.triggers
   * @requires foundation.util.mediaQuery
   */

  var Sticky = function () {
    /**
     * Creates a new instance of a sticky thing.
     * @class
     * @param {jQuery} element - jQuery object to make sticky.
     * @param {Object} options - options object passed when creating the element programmatically.
     */

    function Sticky(element, options) {
      _classCallCheck(this, Sticky);

      this.$element = element;
      this.options = $.extend({}, Sticky.defaults, this.$element.data(), options);

      this._init();

      Foundation.registerPlugin(this, 'Sticky');
    }

    /**
     * Initializes the sticky element by adding classes, getting/setting dimensions, breakpoints and attributes
     * @function
     * @private
     */


    _createClass(Sticky, [{
      key: '_init',
      value: function _init() {
        var $parent = this.$element.parent('[data-sticky-container]'),
            id = this.$element[0].id || Foundation.GetYoDigits(6, 'sticky'),
            _this = this;

        if (!$parent.length) {
          this.wasWrapped = true;
        }
        this.$container = $parent.length ? $parent : $(this.options.container).wrapInner(this.$element);
        this.$container.addClass(this.options.containerClass);

        this.$element.addClass(this.options.stickyClass).attr({ 'data-resize': id });

        this.scrollCount = this.options.checkEvery;
        this.isStuck = false;
        $(window).one('load.zf.sticky', function () {
          if (_this.options.anchor !== '') {
            _this.$anchor = $('#' + _this.options.anchor);
          } else {
            _this._parsePoints();
          }

          _this._setSizes(function () {
            _this._calc(false);
          });
          _this._events(id.split('-').reverse().join('-'));
        });
      }

      /**
       * If using multiple elements as anchors, calculates the top and bottom pixel values the sticky thing should stick and unstick on.
       * @function
       * @private
       */

    }, {
      key: '_parsePoints',
      value: function _parsePoints() {
        var top = this.options.topAnchor,
            btm = this.options.btmAnchor,
            pts = [top, btm],
            breaks = {};
        if (top && btm) {

          for (var i = 0, len = pts.length; i < len && pts[i]; i++) {
            var pt;
            if (typeof pts[i] === 'number') {
              pt = pts[i];
            } else {
              var place = pts[i].split(':'),
                  anchor = $('#' + place[0]);

              pt = anchor.offset().top;
              if (place[1] && place[1].toLowerCase() === 'bottom') {
                pt += anchor[0].getBoundingClientRect().height;
              }
            }
            breaks[i] = pt;
          }
        } else {
          breaks = { 0: 1, 1: document.documentElement.scrollHeight };
        }

        this.points = breaks;
        return;
      }

      /**
       * Adds event handlers for the scrolling element.
       * @private
       * @param {String} id - psuedo-random id for unique scroll event listener.
       */

    }, {
      key: '_events',
      value: function _events(id) {
        var _this = this,
            scrollListener = this.scrollListener = 'scroll.zf.' + id;
        if (this.isOn) {
          return;
        }
        if (this.canStick) {
          this.isOn = true;
          $(window).off(scrollListener).on(scrollListener, function (e) {
            if (_this.scrollCount === 0) {
              _this.scrollCount = _this.options.checkEvery;
              _this._setSizes(function () {
                _this._calc(false, window.pageYOffset);
              });
            } else {
              _this.scrollCount--;
              _this._calc(false, window.pageYOffset);
            }
          });
        }

        this.$element.off('resizeme.zf.trigger').on('resizeme.zf.trigger', function (e, el) {
          _this._setSizes(function () {
            _this._calc(false);
            if (_this.canStick) {
              if (!_this.isOn) {
                _this._events(id);
              }
            } else if (_this.isOn) {
              _this._pauseListeners(scrollListener);
            }
          });
        });
      }

      /**
       * Removes event handlers for scroll and change events on anchor.
       * @fires Sticky#pause
       * @param {String} scrollListener - unique, namespaced scroll listener attached to `window`
       */

    }, {
      key: '_pauseListeners',
      value: function _pauseListeners(scrollListener) {
        this.isOn = false;
        $(window).off(scrollListener);

        /**
         * Fires when the plugin is paused due to resize event shrinking the view.
         * @event Sticky#pause
         * @private
         */
        this.$element.trigger('pause.zf.sticky');
      }

      /**
       * Called on every `scroll` event and on `_init`
       * fires functions based on booleans and cached values
       * @param {Boolean} checkSizes - true if plugin should recalculate sizes and breakpoints.
       * @param {Number} scroll - current scroll position passed from scroll event cb function. If not passed, defaults to `window.pageYOffset`.
       */

    }, {
      key: '_calc',
      value: function _calc(checkSizes, scroll) {
        if (checkSizes) {
          this._setSizes();
        }

        if (!this.canStick) {
          if (this.isStuck) {
            this._removeSticky(true);
          }
          return false;
        }

        if (!scroll) {
          scroll = window.pageYOffset;
        }

        if (scroll >= this.topPoint) {
          if (scroll <= this.bottomPoint) {
            if (!this.isStuck) {
              this._setSticky();
            }
          } else {
            if (this.isStuck) {
              this._removeSticky(false);
            }
          }
        } else {
          if (this.isStuck) {
            this._removeSticky(true);
          }
        }
      }

      /**
       * Causes the $element to become stuck.
       * Adds `position: fixed;`, and helper classes.
       * @fires Sticky#stuckto
       * @function
       * @private
       */

    }, {
      key: '_setSticky',
      value: function _setSticky() {
        var stickTo = this.options.stickTo,
            mrgn = stickTo === 'top' ? 'marginTop' : 'marginBottom',
            notStuckTo = stickTo === 'top' ? 'bottom' : 'top',
            css = {};

        css[mrgn] = this.options[mrgn] + 'em';
        css[stickTo] = 0;
        css[notStuckTo] = 'auto';
        css['left'] = this.$container.offset().left + parseInt(window.getComputedStyle(this.$container[0])["padding-left"], 10);
        this.isStuck = true;
        this.$element.removeClass('is-anchored is-at-' + notStuckTo).addClass('is-stuck is-at-' + stickTo).css(css)
        /**
         * Fires when the $element has become `position: fixed;`
         * Namespaced to `top` or `bottom`, e.g. `sticky.zf.stuckto:top`
         * @event Sticky#stuckto
         */
        .trigger('sticky.zf.stuckto:' + stickTo);
      }

      /**
       * Causes the $element to become unstuck.
       * Removes `position: fixed;`, and helper classes.
       * Adds other helper classes.
       * @param {Boolean} isTop - tells the function if the $element should anchor to the top or bottom of its $anchor element.
       * @fires Sticky#unstuckfrom
       * @private
       */

    }, {
      key: '_removeSticky',
      value: function _removeSticky(isTop) {
        var stickTo = this.options.stickTo,
            stickToTop = stickTo === 'top',
            css = {},
            anchorPt = (this.points ? this.points[1] - this.points[0] : this.anchorHeight) - this.elemHeight,
            mrgn = stickToTop ? 'marginTop' : 'marginBottom',
            notStuckTo = stickToTop ? 'bottom' : 'top',
            topOrBottom = isTop ? 'top' : 'bottom';

        css[mrgn] = 0;

        if (isTop && !stickToTop || stickToTop && !isTop) {
          css[stickTo] = anchorPt;
          css[notStuckTo] = 0;
        } else {
          css[stickTo] = 0;
          css[notStuckTo] = anchorPt;
        }

        css['left'] = '';
        this.isStuck = false;
        this.$element.removeClass('is-stuck is-at-' + stickTo).addClass('is-anchored is-at-' + topOrBottom).css(css)
        /**
         * Fires when the $element has become anchored.
         * Namespaced to `top` or `bottom`, e.g. `sticky.zf.unstuckfrom:bottom`
         * @event Sticky#unstuckfrom
         */
        .trigger('sticky.zf.unstuckfrom:' + topOrBottom);
      }

      /**
       * Sets the $element and $container sizes for plugin.
       * Calls `_setBreakPoints`.
       * @param {Function} cb - optional callback function to fire on completion of `_setBreakPoints`.
       * @private
       */

    }, {
      key: '_setSizes',
      value: function _setSizes(cb) {
        this.canStick = Foundation.MediaQuery.atLeast(this.options.stickyOn);
        if (!this.canStick) {
          cb();
        }
        var _this = this,
            newElemWidth = this.$container[0].getBoundingClientRect().width,
            comp = window.getComputedStyle(this.$container[0]),
            pdng = parseInt(comp['padding-right'], 10);

        if (this.$anchor && this.$anchor.length) {
          this.anchorHeight = this.$anchor[0].getBoundingClientRect().height;
        } else {
          this._parsePoints();
        }

        this.$element.css({
          'max-width': newElemWidth - pdng + 'px'
        });

        var newContainerHeight = this.$element[0].getBoundingClientRect().height || this.containerHeight;
        this.containerHeight = newContainerHeight;
        this.$container.css({
          height: newContainerHeight
        });
        this.elemHeight = newContainerHeight;

        if (this.isStuck) {
          this.$element.css({ "left": this.$container.offset().left + parseInt(comp['padding-left'], 10) });
        }

        this._setBreakPoints(newContainerHeight, function () {
          if (cb) {
            cb();
          }
        });
      }

      /**
       * Sets the upper and lower breakpoints for the element to become sticky/unsticky.
       * @param {Number} elemHeight - px value for sticky.$element height, calculated by `_setSizes`.
       * @param {Function} cb - optional callback function to be called on completion.
       * @private
       */

    }, {
      key: '_setBreakPoints',
      value: function _setBreakPoints(elemHeight, cb) {
        if (!this.canStick) {
          if (cb) {
            cb();
          } else {
            return false;
          }
        }
        var mTop = emCalc(this.options.marginTop),
            mBtm = emCalc(this.options.marginBottom),
            topPoint = this.points ? this.points[0] : this.$anchor.offset().top,
            bottomPoint = this.points ? this.points[1] : topPoint + this.anchorHeight,

        // topPoint = this.$anchor.offset().top || this.points[0],
        // bottomPoint = topPoint + this.anchorHeight || this.points[1],
        winHeight = window.innerHeight;

        if (this.options.stickTo === 'top') {
          topPoint -= mTop;
          bottomPoint -= elemHeight + mTop;
        } else if (this.options.stickTo === 'bottom') {
          topPoint -= winHeight - (elemHeight + mBtm);
          bottomPoint -= winHeight - mBtm;
        } else {
          //this would be the stickTo: both option... tricky
        }

        this.topPoint = topPoint;
        this.bottomPoint = bottomPoint;

        if (cb) {
          cb();
        }
      }

      /**
       * Destroys the current sticky element.
       * Resets the element to the top position first.
       * Removes event listeners, JS-added css properties and classes, and unwraps the $element if the JS added the $container.
       * @function
       */

    }, {
      key: 'destroy',
      value: function destroy() {
        this._removeSticky(true);

        this.$element.removeClass(this.options.stickyClass + ' is-anchored is-at-top').css({
          height: '',
          top: '',
          bottom: '',
          'max-width': ''
        }).off('resizeme.zf.trigger');

        this.$anchor.off('change.zf.sticky');
        $(window).off(this.scrollListener);

        if (this.wasWrapped) {
          this.$element.unwrap();
        } else {
          this.$container.removeClass(this.options.containerClass).css({
            height: ''
          });
        }
        Foundation.unregisterPlugin(this);
      }
    }]);

    return Sticky;
  }();

  Sticky.defaults = {
    /**
     * Customizable container template. Add your own classes for styling and sizing.
     * @option
     * @example '&lt;div data-sticky-container class="small-6 columns"&gt;&lt;/div&gt;'
     */
    container: '<div data-sticky-container></div>',
    /**
     * Location in the view the element sticks to.
     * @option
     * @example 'top'
     */
    stickTo: 'top',
    /**
     * If anchored to a single element, the id of that element.
     * @option
     * @example 'exampleId'
     */
    anchor: '',
    /**
     * If using more than one element as anchor points, the id of the top anchor.
     * @option
     * @example 'exampleId:top'
     */
    topAnchor: '',
    /**
     * If using more than one element as anchor points, the id of the bottom anchor.
     * @option
     * @example 'exampleId:bottom'
     */
    btmAnchor: '',
    /**
     * Margin, in `em`'s to apply to the top of the element when it becomes sticky.
     * @option
     * @example 1
     */
    marginTop: 1,
    /**
     * Margin, in `em`'s to apply to the bottom of the element when it becomes sticky.
     * @option
     * @example 1
     */
    marginBottom: 1,
    /**
     * Breakpoint string that is the minimum screen size an element should become sticky.
     * @option
     * @example 'medium'
     */
    stickyOn: 'medium',
    /**
     * Class applied to sticky element, and removed on destruction. Foundation defaults to `sticky`.
     * @option
     * @example 'sticky'
     */
    stickyClass: 'sticky',
    /**
     * Class applied to sticky container. Foundation defaults to `sticky-container`.
     * @option
     * @example 'sticky-container'
     */
    containerClass: 'sticky-container',
    /**
     * Number of scroll events between the plugin's recalculating sticky points. Setting it to `0` will cause it to recalc every scroll event, setting it to `-1` will prevent recalc on scroll.
     * @option
     * @example 50
     */
    checkEvery: -1
  };

  /**
   * Helper function to calculate em values
   * @param Number {em} - number of em's to calculate into pixels
   */
  function emCalc(em) {
    return parseInt(window.getComputedStyle(document.body, null).fontSize, 10) * em;
  }

  // Window exports
  Foundation.plugin(Sticky, 'Sticky');
}(jQuery);