/**!

* @fileOverview Kickass library to create and place poppers near their reference elements.
* @version 1.14.6
* @license
* Copyright (c) 2016 Federico Zivolo and contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/

(function (global, factory) {

typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
typeof define === 'function' && define.amd ? define(factory) :
(global.Popper = factory());

}(this, (function () { 'use strict';

var isBrowser = typeof window !== 'undefined' && typeof document !== 'undefined';

var longerTimeoutBrowsers = ['Edge', 'Trident', 'Firefox']; var timeoutDuration = 0; for (var i = 0; i < longerTimeoutBrowsers.length; i += 1) {

if (isBrowser && navigator.userAgent.indexOf(longerTimeoutBrowsers[i]) >= 0) {
  timeoutDuration = 1;
  break;
}

}

function microtaskDebounce(fn) {

var called = false;
return function () {
  if (called) {
    return;
  }
  called = true;
  window.Promise.resolve().then(function () {
    called = false;
    fn();
  });
};

}

function taskDebounce(fn) {

var scheduled = false;
return function () {
  if (!scheduled) {
    scheduled = true;
    setTimeout(function () {
      scheduled = false;
      fn();
    }, timeoutDuration);
  }
};

}

var supportsMicroTasks = isBrowser && window.Promise;

/**

*

*/ var debounce = supportsMicroTasks ? microtaskDebounce : taskDebounce;

/**

* Check if the given variable is a function
* @method
* @memberof Popper.Utils
* @argument {Any} functionToCheck - variable to check
* @returns {Boolean} answer to: is a function?
*/

function isFunction(functionToCheck) {

var getType = {};
return functionToCheck && getType.toString.call(functionToCheck) === '[object Function]';

}

/**

* Get CSS computed property of the given element
* @method
* @memberof Popper.Utils
* @argument {Eement} element
* @argument {String} property
*/

function getStyleComputedProperty(element, property) {

if (element.nodeType !== 1) {
  return [];
}
// NOTE: 1 DOM access here
var window = element.ownerDocument.defaultView;
var css = window.getComputedStyle(element, null);
return property ? css[property] : css;

}

/**

* Returns the parentNode or the host of the element
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @returns {Element} parent
*/

function getParentNode(element) {

if (element.nodeName === 'HTML') {
  return element;
}
return element.parentNode || element.host;

}

/**

* Returns the scrolling parent of the given element
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @returns {Element} scroll parent
*/

function getScrollParent(element) {

// Return body, `getScroll` will take care to get the correct `scrollTop` from it
if (!element) {
  return document.body;
}

switch (element.nodeName) {
  case 'HTML':
  case 'BODY':
    return element.ownerDocument.body;
  case '#document':
    return element.body;
}

// Firefox want us to check `-x` and `-y` variations as well

var _getStyleComputedProp = getStyleComputedProperty(element),
    overflow = _getStyleComputedProp.overflow,
    overflowX = _getStyleComputedProp.overflowX,
    overflowY = _getStyleComputedProp.overflowY;

if (/(auto|scroll|overlay)/.test(overflow + overflowY + overflowX)) {
  return element;
}

return getScrollParent(getParentNode(element));

}

var isIE11 = isBrowser && !!(window.MSInputMethodContext && document.documentMode); var isIE10 = isBrowser && /MSIE 10/.test(navigator.userAgent);

/**

* Determines if the browser is Internet Explorer
* @method
* @memberof Popper.Utils
* @param {Number} version to check
* @returns {Boolean} isIE
*/

function isIE(version) {

if (version === 11) {
  return isIE11;
}
if (version === 10) {
  return isIE10;
}
return isIE11 || isIE10;

}

/**

* Returns the offset parent of the given element
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @returns {Element} offset parent
*/

function getOffsetParent(element) {

if (!element) {
  return document.documentElement;
}

var noOffsetParent = isIE(10) ? document.body : null;

// NOTE: 1 DOM access here
var offsetParent = element.offsetParent || null;
// Skip hidden elements which don't have an offsetParent
while (offsetParent === noOffsetParent && element.nextElementSibling) {
  offsetParent = (element = element.nextElementSibling).offsetParent;
}

var nodeName = offsetParent && offsetParent.nodeName;

if (!nodeName || nodeName === 'BODY' || nodeName === 'HTML') {
  return element ? element.ownerDocument.documentElement : document.documentElement;
}

// .offsetParent will return the closest TH, TD or TABLE in case
// no offsetParent is present, I hate this job...
if (['TH', 'TD', 'TABLE'].indexOf(offsetParent.nodeName) !== -1 && getStyleComputedProperty(offsetParent, 'position') === 'static') {
  return getOffsetParent(offsetParent);
}

return offsetParent;

}

function isOffsetContainer(element) {

var nodeName = element.nodeName;

if (nodeName === 'BODY') {
  return false;
}
return nodeName === 'HTML' || getOffsetParent(element.firstElementChild) === element;

}

/**

* Finds the root node (document, shadowDOM root) of the given element
* @method
* @memberof Popper.Utils
* @argument {Element} node
* @returns {Element} root node
*/

function getRoot(node) {

if (node.parentNode !== null) {
  return getRoot(node.parentNode);
}

return node;

}

/**

* Finds the offset parent common to the two provided nodes
* @method
* @memberof Popper.Utils
* @argument {Element} element1
* @argument {Element} element2
* @returns {Element} common offset parent
*/

function findCommonOffsetParent(element1, element2) {

// This check is needed to avoid errors in case one of the elements isn't defined for any reason
if (!element1 || !element1.nodeType || !element2 || !element2.nodeType) {
  return document.documentElement;
}

// Here we make sure to give as "start" the element that comes first in the DOM
var order = element1.compareDocumentPosition(element2) & Node.DOCUMENT_POSITION_FOLLOWING;
var start = order ? element1 : element2;
var end = order ? element2 : element1;

// Get common ancestor container
var range = document.createRange();
range.setStart(start, 0);
range.setEnd(end, 0);
var commonAncestorContainer = range.commonAncestorContainer;

// Both nodes are inside #document

if (element1 !== commonAncestorContainer && element2 !== commonAncestorContainer || start.contains(end)) {
  if (isOffsetContainer(commonAncestorContainer)) {
    return commonAncestorContainer;
  }

  return getOffsetParent(commonAncestorContainer);
}

// one of the nodes is inside shadowDOM, find which one
var element1root = getRoot(element1);
if (element1root.host) {
  return findCommonOffsetParent(element1root.host, element2);
} else {
  return findCommonOffsetParent(element1, getRoot(element2).host);
}

}

/**

* Gets the scroll value of the given element in the given side (top and left)
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @argument {String} side `top` or `left`
* @returns {number} amount of scrolled pixels
*/

function getScroll(element) {

var side = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'top';

var upperSide = side === 'top' ? 'scrollTop' : 'scrollLeft';
var nodeName = element.nodeName;

if (nodeName === 'BODY' || nodeName === 'HTML') {
  var html = element.ownerDocument.documentElement;
  var scrollingElement = element.ownerDocument.scrollingElement || html;
  return scrollingElement[upperSide];
}

return element[upperSide];

}

/*

* Sum or subtract the element scroll values (left and top) from a given rect object
* @method
* @memberof Popper.Utils
* @param {Object} rect - Rect object you want to change
* @param {HTMLElement} element - The element from the function reads the scroll values
* @param {Boolean} subtract - set to true if you want to subtract the scroll values
* @return {Object} rect - The modifier rect object
*/

function includeScroll(rect, element) {

var subtract = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;

var scrollTop = getScroll(element, 'top');
var scrollLeft = getScroll(element, 'left');
var modifier = subtract ? -1 : 1;
rect.top += scrollTop * modifier;
rect.bottom += scrollTop * modifier;
rect.left += scrollLeft * modifier;
rect.right += scrollLeft * modifier;
return rect;

}

/*

* Helper to detect borders of a given element
* @method
* @memberof Popper.Utils
* @param {CSSStyleDeclaration} styles
* Result of `getStyleComputedProperty` on the given element
* @param {String} axis - `x` or `y`
* @return {number} borders - The borders size of the given axis
*/

function getBordersSize(styles, axis) {

var sideA = axis === 'x' ? 'Left' : 'Top';
var sideB = sideA === 'Left' ? 'Right' : 'Bottom';

return parseFloat(styles['border' + sideA + 'Width'], 10) + parseFloat(styles['border' + sideB + 'Width'], 10);

}

function getSize(axis, body, html, computedStyle) {

return Math.max(body['offset' + axis], body['scroll' + axis], html['client' + axis], html['offset' + axis], html['scroll' + axis], isIE(10) ? parseInt(html['offset' + axis]) + parseInt(computedStyle['margin' + (axis === 'Height' ? 'Top' : 'Left')]) + parseInt(computedStyle['margin' + (axis === 'Height' ? 'Bottom' : 'Right')]) : 0);

}

function getWindowSizes(document) {

var body = document.body;
var html = document.documentElement;
var computedStyle = isIE(10) && getComputedStyle(html);

return {
  height: getSize('Height', body, html, computedStyle),
  width: getSize('Width', body, html, computedStyle)
};

}

var classCallCheck = function (instance, Constructor) {

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

};

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 defineProperty = function (obj, key, value) {

if (key in obj) {
  Object.defineProperty(obj, key, {
    value: value,
    enumerable: true,
    configurable: true,
    writable: true
  });
} else {
  obj[key] = value;
}

return obj;

};

var _extends = Object.assign || function (target) {

for (var i = 1; i < arguments.length; i++) {
  var source = arguments[i];

  for (var key in source) {
    if (Object.prototype.hasOwnProperty.call(source, key)) {
      target[key] = source[key];
    }
  }
}

return target;

};

/**

* Given element offsets, generate an output similar to getBoundingClientRect
* @method
* @memberof Popper.Utils
* @argument {Object} offsets
* @returns {Object} ClientRect like output
*/

function getClientRect(offsets) {

return _extends({}, offsets, {
  right: offsets.left + offsets.width,
  bottom: offsets.top + offsets.height
});

}

/**

* Get bounding client rect of given element
* @method
* @memberof Popper.Utils
* @param {HTMLElement} element
* @return {Object} client rect
*/

function getBoundingClientRect(element) {

var rect = {};

// IE10 10 FIX: Please, don't ask, the element isn't
// considered in DOM in some circumstances...
// This isn't reproducible in IE10 compatibility mode of IE11
try {
  if (isIE(10)) {
    rect = element.getBoundingClientRect();
    var scrollTop = getScroll(element, 'top');
    var scrollLeft = getScroll(element, 'left');
    rect.top += scrollTop;
    rect.left += scrollLeft;
    rect.bottom += scrollTop;
    rect.right += scrollLeft;
  } else {
    rect = element.getBoundingClientRect();
  }
} catch (e) {}

var result = {
  left: rect.left,
  top: rect.top,
  width: rect.right - rect.left,
  height: rect.bottom - rect.top
};

// subtract scrollbar size from sizes
var sizes = element.nodeName === 'HTML' ? getWindowSizes(element.ownerDocument) : {};
var width = sizes.width || element.clientWidth || result.right - result.left;
var height = sizes.height || element.clientHeight || result.bottom - result.top;

var horizScrollbar = element.offsetWidth - width;
var vertScrollbar = element.offsetHeight - height;

// if an hypothetical scrollbar is detected, we must be sure it's not a `border`
// we make this check conditional for performance reasons
if (horizScrollbar || vertScrollbar) {
  var styles = getStyleComputedProperty(element);
  horizScrollbar -= getBordersSize(styles, 'x');
  vertScrollbar -= getBordersSize(styles, 'y');

  result.width -= horizScrollbar;
  result.height -= vertScrollbar;
}

return getClientRect(result);

}

function getOffsetRectRelativeToArbitraryNode(children, parent) {

var fixedPosition = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;

var isIE10 = isIE(10);
var isHTML = parent.nodeName === 'HTML';
var childrenRect = getBoundingClientRect(children);
var parentRect = getBoundingClientRect(parent);
var scrollParent = getScrollParent(children);

var styles = getStyleComputedProperty(parent);
var borderTopWidth = parseFloat(styles.borderTopWidth, 10);
var borderLeftWidth = parseFloat(styles.borderLeftWidth, 10);

// In cases where the parent is fixed, we must ignore negative scroll in offset calc
if (fixedPosition && isHTML) {
  parentRect.top = Math.max(parentRect.top, 0);
  parentRect.left = Math.max(parentRect.left, 0);
}
var offsets = getClientRect({
  top: childrenRect.top - parentRect.top - borderTopWidth,
  left: childrenRect.left - parentRect.left - borderLeftWidth,
  width: childrenRect.width,
  height: childrenRect.height
});
offsets.marginTop = 0;
offsets.marginLeft = 0;

// Subtract margins of documentElement in case it's being used as parent
// we do this only on HTML because it's the only element that behaves
// differently when margins are applied to it. The margins are included in
// the box of the documentElement, in the other cases not.
if (!isIE10 && isHTML) {
  var marginTop = parseFloat(styles.marginTop, 10);
  var marginLeft = parseFloat(styles.marginLeft, 10);

  offsets.top -= borderTopWidth - marginTop;
  offsets.bottom -= borderTopWidth - marginTop;
  offsets.left -= borderLeftWidth - marginLeft;
  offsets.right -= borderLeftWidth - marginLeft;

  // Attach marginTop and marginLeft because in some circumstances we may need them
  offsets.marginTop = marginTop;
  offsets.marginLeft = marginLeft;
}

if (isIE10 && !fixedPosition ? parent.contains(scrollParent) : parent === scrollParent && scrollParent.nodeName !== 'BODY') {
  offsets = includeScroll(offsets, parent);
}

return offsets;

}

function getViewportOffsetRectRelativeToArtbitraryNode(element) {

var excludeScroll = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;

var html = element.ownerDocument.documentElement;
var relativeOffset = getOffsetRectRelativeToArbitraryNode(element, html);
var width = Math.max(html.clientWidth, window.innerWidth || 0);
var height = Math.max(html.clientHeight, window.innerHeight || 0);

var scrollTop = !excludeScroll ? getScroll(html) : 0;
var scrollLeft = !excludeScroll ? getScroll(html, 'left') : 0;

var offset = {
  top: scrollTop - relativeOffset.top + relativeOffset.marginTop,
  left: scrollLeft - relativeOffset.left + relativeOffset.marginLeft,
  width: width,
  height: height
};

return getClientRect(offset);

}

/**

* Check if the given element is fixed or is inside a fixed parent
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @argument {Element} customContainer
* @returns {Boolean} answer to "isFixed?"
*/

function isFixed(element) {

var nodeName = element.nodeName;
if (nodeName === 'BODY' || nodeName === 'HTML') {
  return false;
}
if (getStyleComputedProperty(element, 'position') === 'fixed') {
  return true;
}
return isFixed(getParentNode(element));

}

/**

* Finds the first parent of an element that has a transformed property defined
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @returns {Element} first transformed parent or documentElement
*/

function getFixedPositionOffsetParent(element) {

// This check is needed to avoid errors in case one of the elements isn't defined for any reason
if (!element || !element.parentElement || isIE()) {
  return document.documentElement;
}
var el = element.parentElement;
while (el && getStyleComputedProperty(el, 'transform') === 'none') {
  el = el.parentElement;
}
return el || document.documentElement;

}

/**

* Computed the boundaries limits and return them
* @method
* @memberof Popper.Utils
* @param {HTMLElement} popper
* @param {HTMLElement} reference
* @param {number} padding
* @param {HTMLElement} boundariesElement - Element used to define the boundaries
* @param {Boolean} fixedPosition - Is in fixed position mode
* @returns {Object} Coordinates of the boundaries
*/

function getBoundaries(popper, reference, padding, boundariesElement) {

var fixedPosition = arguments.length > 4 && arguments[4] !== undefined ? arguments[4] : false;

// NOTE: 1 DOM access here

var boundaries = { top: 0, left: 0 };
var offsetParent = fixedPosition ? getFixedPositionOffsetParent(popper) : findCommonOffsetParent(popper, reference);

// Handle viewport case
if (boundariesElement === 'viewport') {
  boundaries = getViewportOffsetRectRelativeToArtbitraryNode(offsetParent, fixedPosition);
} else {
  // Handle other cases based on DOM element used as boundaries
  var boundariesNode = void 0;
  if (boundariesElement === 'scrollParent') {
    boundariesNode = getScrollParent(getParentNode(reference));
    if (boundariesNode.nodeName === 'BODY') {
      boundariesNode = popper.ownerDocument.documentElement;
    }
  } else if (boundariesElement === 'window') {
    boundariesNode = popper.ownerDocument.documentElement;
  } else {
    boundariesNode = boundariesElement;
  }

  var offsets = getOffsetRectRelativeToArbitraryNode(boundariesNode, offsetParent, fixedPosition);

  // In case of HTML, we need a different computation
  if (boundariesNode.nodeName === 'HTML' && !isFixed(offsetParent)) {
    var _getWindowSizes = getWindowSizes(popper.ownerDocument),
        height = _getWindowSizes.height,
        width = _getWindowSizes.width;

    boundaries.top += offsets.top - offsets.marginTop;
    boundaries.bottom = height + offsets.top;
    boundaries.left += offsets.left - offsets.marginLeft;
    boundaries.right = width + offsets.left;
  } else {
    // for all the other DOM elements, this one is good
    boundaries = offsets;
  }
}

// Add paddings
padding = padding || 0;
var isPaddingNumber = typeof padding === 'number';
boundaries.left += isPaddingNumber ? padding : padding.left || 0;
boundaries.top += isPaddingNumber ? padding : padding.top || 0;
boundaries.right -= isPaddingNumber ? padding : padding.right || 0;
boundaries.bottom -= isPaddingNumber ? padding : padding.bottom || 0;

return boundaries;

}

function getArea(_ref) {

var width = _ref.width,
    height = _ref.height;

return width * height;

}

/**

* Utility used to transform the `auto` placement to the placement with more
* available space.
* @method
* @memberof Popper.Utils
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function computeAutoPlacement(placement, refRect, popper, reference, boundariesElement) {

var padding = arguments.length > 5 && arguments[5] !== undefined ? arguments[5] : 0;

if (placement.indexOf('auto') === -1) {
  return placement;
}

var boundaries = getBoundaries(popper, reference, padding, boundariesElement);

var rects = {
  top: {
    width: boundaries.width,
    height: refRect.top - boundaries.top
  },
  right: {
    width: boundaries.right - refRect.right,
    height: boundaries.height
  },
  bottom: {
    width: boundaries.width,
    height: boundaries.bottom - refRect.bottom
  },
  left: {
    width: refRect.left - boundaries.left,
    height: boundaries.height
  }
};

var sortedAreas = Object.keys(rects).map(function (key) {
  return _extends({
    key: key
  }, rects[key], {
    area: getArea(rects[key])
  });
}).sort(function (a, b) {
  return b.area - a.area;
});

var filteredAreas = sortedAreas.filter(function (_ref2) {
  var width = _ref2.width,
      height = _ref2.height;
  return width >= popper.clientWidth && height >= popper.clientHeight;
});

var computedPlacement = filteredAreas.length > 0 ? filteredAreas[0].key : sortedAreas[0].key;

var variation = placement.split('-')[1];

return computedPlacement + (variation ? '-' + variation : '');

}

/**

* Get offsets to the reference element
* @method
* @memberof Popper.Utils
* @param {Object} state
* @param {Element} popper - the popper element
* @param {Element} reference - the reference element (the popper will be relative to this)
* @param {Element} fixedPosition - is in fixed position mode
* @returns {Object} An object containing the offsets which will be applied to the popper
*/

function getReferenceOffsets(state, popper, reference) {

var fixedPosition = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : null;

var commonOffsetParent = fixedPosition ? getFixedPositionOffsetParent(popper) : findCommonOffsetParent(popper, reference);
return getOffsetRectRelativeToArbitraryNode(reference, commonOffsetParent, fixedPosition);

}

/**

* Get the outer sizes of the given element (offset size + margins)
* @method
* @memberof Popper.Utils
* @argument {Element} element
* @returns {Object} object containing width and height properties
*/

function getOuterSizes(element) {

var window = element.ownerDocument.defaultView;
var styles = window.getComputedStyle(element);
var x = parseFloat(styles.marginTop || 0) + parseFloat(styles.marginBottom || 0);
var y = parseFloat(styles.marginLeft || 0) + parseFloat(styles.marginRight || 0);
var result = {
  width: element.offsetWidth + y,
  height: element.offsetHeight + x
};
return result;

}

/**

* Get the opposite placement of the given one
* @method
* @memberof Popper.Utils
* @argument {String} placement
* @returns {String} flipped placement
*/

function getOppositePlacement(placement) {

var hash = { left: 'right', right: 'left', bottom: 'top', top: 'bottom' };
return placement.replace(/left|right|bottom|top/g, function (matched) {
  return hash[matched];
});

}

/**

* Get offsets to the popper
* @method
* @memberof Popper.Utils
* @param {Object} position - CSS position the Popper will get applied
* @param {HTMLElement} popper - the popper element
* @param {Object} referenceOffsets - the reference offsets (the popper will be relative to this)
* @param {String} placement - one of the valid placement options
* @returns {Object} popperOffsets - An object containing the offsets which will be applied to the popper
*/

function getPopperOffsets(popper, referenceOffsets, placement) {

placement = placement.split('-')[0];

// Get popper node sizes
var popperRect = getOuterSizes(popper);

// Add position, width and height to our offsets object
var popperOffsets = {
  width: popperRect.width,
  height: popperRect.height
};

// depending by the popper placement we have to compute its offsets slightly differently
var isHoriz = ['right', 'left'].indexOf(placement) !== -1;
var mainSide = isHoriz ? 'top' : 'left';
var secondarySide = isHoriz ? 'left' : 'top';
var measurement = isHoriz ? 'height' : 'width';
var secondaryMeasurement = !isHoriz ? 'height' : 'width';

popperOffsets[mainSide] = referenceOffsets[mainSide] + referenceOffsets[measurement] / 2 - popperRect[measurement] / 2;
if (placement === secondarySide) {
  popperOffsets[secondarySide] = referenceOffsets[secondarySide] - popperRect[secondaryMeasurement];
} else {
  popperOffsets[secondarySide] = referenceOffsets[getOppositePlacement(secondarySide)];
}

return popperOffsets;

}

/**

* Mimics the `find` method of Array
* @method
* @memberof Popper.Utils
* @argument {Array} arr
* @argument prop
* @argument value
* @returns index or -1
*/

function find(arr, check) {

// use native find if supported
if (Array.prototype.find) {
  return arr.find(check);
}

// use `filter` to obtain the same behavior of `find`
return arr.filter(check)[0];

}

/**

* Return the index of the matching object
* @method
* @memberof Popper.Utils
* @argument {Array} arr
* @argument prop
* @argument value
* @returns index or -1
*/

function findIndex(arr, prop, value) {

// use native findIndex if supported
if (Array.prototype.findIndex) {
  return arr.findIndex(function (cur) {
    return cur[prop] === value;
  });
}

// use `find` + `indexOf` if `findIndex` isn't supported
var match = find(arr, function (obj) {
  return obj[prop] === value;
});
return arr.indexOf(match);

}

/**

* Loop trough the list of modifiers and run them in order,
* each of them will then edit the data object.
* @method
* @memberof Popper.Utils
* @param {dataObject} data
* @param {Array} modifiers
* @param {String} ends - Optional modifier name used as stopper
* @returns {dataObject}
*/

function runModifiers(modifiers, data, ends) {

var modifiersToRun = ends === undefined ? modifiers : modifiers.slice(0, findIndex(modifiers, 'name', ends));

modifiersToRun.forEach(function (modifier) {
  if (modifier['function']) {
    // eslint-disable-line dot-notation
    console.warn('`modifier.function` is deprecated, use `modifier.fn`!');
  }
  var fn = modifier['function'] || modifier.fn; // eslint-disable-line dot-notation
  if (modifier.enabled && isFunction(fn)) {
    // Add properties to offsets to make them a complete clientRect object
    // we do this before each modifier to make sure the previous one doesn't
    // mess with these values
    data.offsets.popper = getClientRect(data.offsets.popper);
    data.offsets.reference = getClientRect(data.offsets.reference);

    data = fn(data, modifier);
  }
});

return data;

}

/**

* Updates the position of the popper, computing the new offsets and applying
* the new style.<br />
* Prefer `scheduleUpdate` over `update` because of performance reasons.
* @method
* @memberof Popper
*/

function update() {

// if popper is destroyed, don't perform any further update
if (this.state.isDestroyed) {
  return;
}

var data = {
  instance: this,
  styles: {},
  arrowStyles: {},
  attributes: {},
  flipped: false,
  offsets: {}
};

// compute reference element offsets
data.offsets.reference = getReferenceOffsets(this.state, this.popper, this.reference, this.options.positionFixed);

// compute auto placement, store placement inside the data object,
// modifiers will be able to edit `placement` if needed
// and refer to originalPlacement to know the original value
data.placement = computeAutoPlacement(this.options.placement, data.offsets.reference, this.popper, this.reference, this.options.modifiers.flip.boundariesElement, this.options.modifiers.flip.padding);

// store the computed placement inside `originalPlacement`
data.originalPlacement = data.placement;

data.positionFixed = this.options.positionFixed;

// compute the popper offsets
data.offsets.popper = getPopperOffsets(this.popper, data.offsets.reference, data.placement);

data.offsets.popper.position = this.options.positionFixed ? 'fixed' : 'absolute';

// run the modifiers
data = runModifiers(this.modifiers, data);

// the first `update` will call `onCreate` callback
// the other ones will call `onUpdate` callback
if (!this.state.isCreated) {
  this.state.isCreated = true;
  this.options.onCreate(data);
} else {
  this.options.onUpdate(data);
}

}

/**

* Helper used to know if the given modifier is enabled.
* @method
* @memberof Popper.Utils
* @returns {Boolean}
*/

function isModifierEnabled(modifiers, modifierName) {

return modifiers.some(function (_ref) {
  var name = _ref.name,
      enabled = _ref.enabled;
  return enabled && name === modifierName;
});

}

/**

* Get the prefixed supported property name
* @method
* @memberof Popper.Utils
* @argument {String} property (camelCase)
* @returns {String} prefixed property (camelCase or PascalCase, depending on the vendor prefix)
*/

function getSupportedPropertyName(property) {

var prefixes = [false, 'ms', 'Webkit', 'Moz', 'O'];
var upperProp = property.charAt(0).toUpperCase() + property.slice(1);

for (var i = 0; i < prefixes.length; i++) {
  var prefix = prefixes[i];
  var toCheck = prefix ? '' + prefix + upperProp : property;
  if (typeof document.body.style[toCheck] !== 'undefined') {
    return toCheck;
  }
}
return null;

}

/**

* Destroys the popper.
* @method
* @memberof Popper
*/

function destroy() {

this.state.isDestroyed = true;

// touch DOM only if `applyStyle` modifier is enabled
if (isModifierEnabled(this.modifiers, 'applyStyle')) {
  this.popper.removeAttribute('x-placement');
  this.popper.style.position = '';
  this.popper.style.top = '';
  this.popper.style.left = '';
  this.popper.style.right = '';
  this.popper.style.bottom = '';
  this.popper.style.willChange = '';
  this.popper.style[getSupportedPropertyName('transform')] = '';
}

this.disableEventListeners();

// remove the popper if user explicity asked for the deletion on destroy
// do not use `remove` because IE11 doesn't support it
if (this.options.removeOnDestroy) {
  this.popper.parentNode.removeChild(this.popper);
}
return this;

}

/**

* Get the window associated with the element
* @argument {Element} element
* @returns {Window}
*/

function getWindow(element) {

var ownerDocument = element.ownerDocument;
return ownerDocument ? ownerDocument.defaultView : window;

}

function attachToScrollParents(scrollParent, event, callback, scrollParents) {

var isBody = scrollParent.nodeName === 'BODY';
var target = isBody ? scrollParent.ownerDocument.defaultView : scrollParent;
target.addEventListener(event, callback, { passive: true });

if (!isBody) {
  attachToScrollParents(getScrollParent(target.parentNode), event, callback, scrollParents);
}
scrollParents.push(target);

}

/**

* Setup needed event listeners used to update the popper position
* @method
* @memberof Popper.Utils
* @private
*/

function setupEventListeners(reference, options, state, updateBound) {

// Resize event listener on window
state.updateBound = updateBound;
getWindow(reference).addEventListener('resize', state.updateBound, { passive: true });

// Scroll event listener on scroll parents
var scrollElement = getScrollParent(reference);
attachToScrollParents(scrollElement, 'scroll', state.updateBound, state.scrollParents);
state.scrollElement = scrollElement;
state.eventsEnabled = true;

return state;

}

/**

* It will add resize/scroll events and start recalculating
* position of the popper element when they are triggered.
* @method
* @memberof Popper
*/

function enableEventListeners() {

if (!this.state.eventsEnabled) {
  this.state = setupEventListeners(this.reference, this.options, this.state, this.scheduleUpdate);
}

}

/**

* Remove event listeners used to update the popper position
* @method
* @memberof Popper.Utils
* @private
*/

function removeEventListeners(reference, state) {

// Remove resize event listener on window
getWindow(reference).removeEventListener('resize', state.updateBound);

// Remove scroll event listener on scroll parents
state.scrollParents.forEach(function (target) {
  target.removeEventListener('scroll', state.updateBound);
});

// Reset state
state.updateBound = null;
state.scrollParents = [];
state.scrollElement = null;
state.eventsEnabled = false;
return state;

}

/**

* It will remove resize/scroll events and won't recalculate popper position
* when they are triggered. It also won't trigger `onUpdate` callback anymore,
* unless you call `update` method manually.
* @method
* @memberof Popper
*/

function disableEventListeners() {

if (this.state.eventsEnabled) {
  cancelAnimationFrame(this.scheduleUpdate);
  this.state = removeEventListeners(this.reference, this.state);
}

}

/**

* Tells if a given input is a number
* @method
* @memberof Popper.Utils
* @param {*} input to check
* @return {Boolean}
*/

function isNumeric(n) {

return n !== '' && !isNaN(parseFloat(n)) && isFinite(n);

}

/**

* Set the style to the given popper
* @method
* @memberof Popper.Utils
* @argument {Element} element - Element to apply the style to
* @argument {Object} styles
* Object with a list of properties and values which will be applied to the element
*/

function setStyles(element, styles) {

Object.keys(styles).forEach(function (prop) {
  var unit = '';
  // add unit if the value is numeric and is one of the following
  if (['width', 'height', 'top', 'right', 'bottom', 'left'].indexOf(prop) !== -1 && isNumeric(styles[prop])) {
    unit = 'px';
  }
  element.style[prop] = styles[prop] + unit;
});

}

/**

* Set the attributes to the given popper
* @method
* @memberof Popper.Utils
* @argument {Element} element - Element to apply the attributes to
* @argument {Object} styles
* Object with a list of properties and values which will be applied to the element
*/

function setAttributes(element, attributes) {

Object.keys(attributes).forEach(function (prop) {
  var value = attributes[prop];
  if (value !== false) {
    element.setAttribute(prop, attributes[prop]);
  } else {
    element.removeAttribute(prop);
  }
});

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by `update` method
* @argument {Object} data.styles - List of style properties - values to apply to popper element
* @argument {Object} data.attributes - List of attribute properties - values to apply to popper element
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The same data object
*/

function applyStyle(data) {

// any property present in `data.styles` will be applied to the popper,
// in this way we can make the 3rd party modifiers add custom styles to it
// Be aware, modifiers could override the properties defined in the previous
// lines of this modifier!
setStyles(data.instance.popper, data.styles);

// any property present in `data.attributes` will be applied to the popper,
// they will be set as HTML attributes of the element
setAttributes(data.instance.popper, data.attributes);

// if arrowElement is defined and arrowStyles has some properties
if (data.arrowElement && Object.keys(data.arrowStyles).length) {
  setStyles(data.arrowElement, data.arrowStyles);
}

return data;

}

/**

* Set the x-placement attribute before everything else because it could be used
* to add margins to the popper margins needs to be calculated to get the
* correct popper offsets.
* @method
* @memberof Popper.modifiers
* @param {HTMLElement} reference - The reference element used to position the popper
* @param {HTMLElement} popper - The HTML element used as popper
* @param {Object} options - Popper.js options
*/

function applyStyleOnLoad(reference, popper, options, modifierOptions, state) {

// compute reference element offsets
var referenceOffsets = getReferenceOffsets(state, popper, reference, options.positionFixed);

// compute auto placement, store placement inside the data object,
// modifiers will be able to edit `placement` if needed
// and refer to originalPlacement to know the original value
var placement = computeAutoPlacement(options.placement, referenceOffsets, popper, reference, options.modifiers.flip.boundariesElement, options.modifiers.flip.padding);

popper.setAttribute('x-placement', placement);

// Apply `position` to popper before anything else because
// without the position applied we can't guarantee correct computations
setStyles(popper, { position: options.positionFixed ? 'fixed' : 'absolute' });

return options;

}

/**

* @function
* @memberof Popper.Utils
* @argument {Object} data - The data object generated by `update` method
* @argument {Boolean} shouldRound - If the offsets should be rounded at all
* @returns {Object} The popper's position offsets rounded
*
* The tale of pixel-perfect positioning. It's still not 100% perfect, but as
* good as it can be within reason.
* Discussion here: https://github.com/FezVrasta/popper.js/pull/715
*
* Low DPI screens cause a popper to be blurry if not using full pixels (Safari
* as well on High DPI screens).
*
* Firefox prefers no rounding for positioning and does not have blurriness on
* high DPI screens.
*
* Only horizontal placement and left/right values need to be considered.
*/

function getRoundedOffsets(data, shouldRound) {

var _data$offsets = data.offsets,
    popper = _data$offsets.popper,
    reference = _data$offsets.reference;

var isVertical = ['left', 'right'].indexOf(data.placement) !== -1;
var isVariation = data.placement.indexOf('-') !== -1;
var sameWidthOddness = reference.width % 2 === popper.width % 2;
var bothOddWidth = reference.width % 2 === 1 && popper.width % 2 === 1;
var noRound = function noRound(v) {
  return v;
};

var horizontalToInteger = !shouldRound ? noRound : isVertical || isVariation || sameWidthOddness ? Math.round : Math.floor;
var verticalToInteger = !shouldRound ? noRound : Math.round;

return {
  left: horizontalToInteger(bothOddWidth && !isVariation && shouldRound ? popper.left - 1 : popper.left),
  top: verticalToInteger(popper.top),
  bottom: verticalToInteger(popper.bottom),
  right: horizontalToInteger(popper.right)
};

}

var isFirefox = isBrowser && /Firefox/i.test(navigator.userAgent);

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by `update` method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function computeStyle(data, options) {

var x = options.x,
    y = options.y;
var popper = data.offsets.popper;

// Remove this legacy support in Popper.js v2

var legacyGpuAccelerationOption = find(data.instance.modifiers, function (modifier) {
  return modifier.name === 'applyStyle';
}).gpuAcceleration;
if (legacyGpuAccelerationOption !== undefined) {
  console.warn('WARNING: `gpuAcceleration` option moved to `computeStyle` modifier and will not be supported in future versions of Popper.js!');
}
var gpuAcceleration = legacyGpuAccelerationOption !== undefined ? legacyGpuAccelerationOption : options.gpuAcceleration;

var offsetParent = getOffsetParent(data.instance.popper);
var offsetParentRect = getBoundingClientRect(offsetParent);

// Styles
var styles = {
  position: popper.position
};

var offsets = getRoundedOffsets(data, window.devicePixelRatio < 2 || !isFirefox);

var sideA = x === 'bottom' ? 'top' : 'bottom';
var sideB = y === 'right' ? 'left' : 'right';

// if gpuAcceleration is set to `true` and transform is supported,
//  we use `translate3d` to apply the position to the popper we
// automatically use the supported prefixed version if needed
var prefixedProperty = getSupportedPropertyName('transform');

// now, let's make a step back and look at this code closely (wtf?)
// If the content of the popper grows once it's been positioned, it
// may happen that the popper gets misplaced because of the new content
// overflowing its reference element
// To avoid this problem, we provide two options (x and y), which allow
// the consumer to define the offset origin.
// If we position a popper on top of a reference element, we can set
// `x` to `top` to make the popper grow towards its top instead of
// its bottom.
var left = void 0,
    top = void 0;
if (sideA === 'bottom') {
  // when offsetParent is <html> the positioning is relative to the bottom of the screen (excluding the scrollbar)
  // and not the bottom of the html element
  if (offsetParent.nodeName === 'HTML') {
    top = -offsetParent.clientHeight + offsets.bottom;
  } else {
    top = -offsetParentRect.height + offsets.bottom;
  }
} else {
  top = offsets.top;
}
if (sideB === 'right') {
  if (offsetParent.nodeName === 'HTML') {
    left = -offsetParent.clientWidth + offsets.right;
  } else {
    left = -offsetParentRect.width + offsets.right;
  }
} else {
  left = offsets.left;
}
if (gpuAcceleration && prefixedProperty) {
  styles[prefixedProperty] = 'translate3d(' + left + 'px, ' + top + 'px, 0)';
  styles[sideA] = 0;
  styles[sideB] = 0;
  styles.willChange = 'transform';
} else {
  // othwerise, we use the standard `top`, `left`, `bottom` and `right` properties
  var invertTop = sideA === 'bottom' ? -1 : 1;
  var invertLeft = sideB === 'right' ? -1 : 1;
  styles[sideA] = top * invertTop;
  styles[sideB] = left * invertLeft;
  styles.willChange = sideA + ', ' + sideB;
}

// Attributes
var attributes = {
  'x-placement': data.placement
};

// Update `data` attributes, styles and arrowStyles
data.attributes = _extends({}, attributes, data.attributes);
data.styles = _extends({}, styles, data.styles);
data.arrowStyles = _extends({}, data.offsets.arrow, data.arrowStyles);

return data;

}

/**

* Helper used to know if the given modifier depends from another one.<br />
* It checks if the needed modifier is listed and enabled.
* @method
* @memberof Popper.Utils
* @param {Array} modifiers - list of modifiers
* @param {String} requestingName - name of requesting modifier
* @param {String} requestedName - name of requested modifier
* @returns {Boolean}
*/

function isModifierRequired(modifiers, requestingName, requestedName) {

var requesting = find(modifiers, function (_ref) {
  var name = _ref.name;
  return name === requestingName;
});

var isRequired = !!requesting && modifiers.some(function (modifier) {
  return modifier.name === requestedName && modifier.enabled && modifier.order < requesting.order;
});

if (!isRequired) {
  var _requesting = '`' + requestingName + '`';
  var requested = '`' + requestedName + '`';
  console.warn(requested + ' modifier is required by ' + _requesting + ' modifier in order to work, be sure to include it before ' + _requesting + '!');
}
return isRequired;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function arrow(data, options) {

var _data$offsets$arrow;

// arrow depends on keepTogether in order to work
if (!isModifierRequired(data.instance.modifiers, 'arrow', 'keepTogether')) {
  return data;
}

var arrowElement = options.element;

// if arrowElement is a string, suppose it's a CSS selector
if (typeof arrowElement === 'string') {
  arrowElement = data.instance.popper.querySelector(arrowElement);

  // if arrowElement is not found, don't run the modifier
  if (!arrowElement) {
    return data;
  }
} else {
  // if the arrowElement isn't a query selector we must check that the
  // provided DOM node is child of its popper node
  if (!data.instance.popper.contains(arrowElement)) {
    console.warn('WARNING: `arrow.element` must be child of its popper element!');
    return data;
  }
}

var placement = data.placement.split('-')[0];
var _data$offsets = data.offsets,
    popper = _data$offsets.popper,
    reference = _data$offsets.reference;

var isVertical = ['left', 'right'].indexOf(placement) !== -1;

var len = isVertical ? 'height' : 'width';
var sideCapitalized = isVertical ? 'Top' : 'Left';
var side = sideCapitalized.toLowerCase();
var altSide = isVertical ? 'left' : 'top';
var opSide = isVertical ? 'bottom' : 'right';
var arrowElementSize = getOuterSizes(arrowElement)[len];

//
// extends keepTogether behavior making sure the popper and its
// reference have enough pixels in conjunction
//

// top/left side
if (reference[opSide] - arrowElementSize < popper[side]) {
  data.offsets.popper[side] -= popper[side] - (reference[opSide] - arrowElementSize);
}
// bottom/right side
if (reference[side] + arrowElementSize > popper[opSide]) {
  data.offsets.popper[side] += reference[side] + arrowElementSize - popper[opSide];
}
data.offsets.popper = getClientRect(data.offsets.popper);

// compute center of the popper
var center = reference[side] + reference[len] / 2 - arrowElementSize / 2;

// Compute the sideValue using the updated popper offsets
// take popper margin in account because we don't have this info available
var css = getStyleComputedProperty(data.instance.popper);
var popperMarginSide = parseFloat(css['margin' + sideCapitalized], 10);
var popperBorderSide = parseFloat(css['border' + sideCapitalized + 'Width'], 10);
var sideValue = center - data.offsets.popper[side] - popperMarginSide - popperBorderSide;

// prevent arrowElement from being placed not contiguously to its popper
sideValue = Math.max(Math.min(popper[len] - arrowElementSize, sideValue), 0);

data.arrowElement = arrowElement;
data.offsets.arrow = (_data$offsets$arrow = {}, defineProperty(_data$offsets$arrow, side, Math.round(sideValue)), defineProperty(_data$offsets$arrow, altSide, ''), _data$offsets$arrow);

return data;

}

/**

* Get the opposite placement variation of the given one
* @method
* @memberof Popper.Utils
* @argument {String} placement variation
* @returns {String} flipped placement variation
*/

function getOppositeVariation(variation) {

if (variation === 'end') {
  return 'start';
} else if (variation === 'start') {
  return 'end';
}
return variation;

}

/**

* List of accepted placements to use as values of the `placement` option.<br />
* Valid placements are:
* - `auto`
* - `top`
* - `right`
* - `bottom`
* - `left`
*
* Each placement can have a variation from this list:
* - `-start`
* - `-end`
*
* Variations are interpreted easily if you think of them as the left to right
* written languages. Horizontally (`top` and `bottom`), `start` is left and `end`
* is right.<br />
* Vertically (`left` and `right`), `start` is top and `end` is bottom.
*
* Some valid examples are:
* - `top-end` (on top of reference, right aligned)
* - `right-start` (on right of reference, top aligned)
* - `bottom` (on bottom, centered)
* - `auto-end` (on the side with more space available, alignment depends by placement)
*
* @static
* @type {Array}
* @enum {String}
* @readonly
* @method placements
* @memberof Popper
*/

var placements = ['auto-start', 'auto', 'auto-end', 'top-start', 'top', 'top-end', 'right-start', 'right', 'right-end', 'bottom-end', 'bottom', 'bottom-start', 'left-end', 'left', 'left-start'];

// Get rid of `auto` `auto-start` and `auto-end` var validPlacements = placements.slice(3);

/**

* Given an initial placement, returns all the subsequent placements
* clockwise (or counter-clockwise).
*
* @method
* @memberof Popper.Utils
* @argument {String} placement - A valid placement (it accepts variations)
* @argument {Boolean} counter - Set to true to walk the placements counterclockwise
* @returns {Array} placements including their variations
*/

function clockwise(placement) {

var counter = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;

var index = validPlacements.indexOf(placement);
var arr = validPlacements.slice(index + 1).concat(validPlacements.slice(0, index));
return counter ? arr.reverse() : arr;

}

var BEHAVIORS = {

FLIP: 'flip',
CLOCKWISE: 'clockwise',
COUNTERCLOCKWISE: 'counterclockwise'

};

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function flip(data, options) {

// if `inner` modifier is enabled, we can't use the `flip` modifier
if (isModifierEnabled(data.instance.modifiers, 'inner')) {
  return data;
}

if (data.flipped && data.placement === data.originalPlacement) {
  // seems like flip is trying to loop, probably there's not enough space on any of the flippable sides
  return data;
}

var boundaries = getBoundaries(data.instance.popper, data.instance.reference, options.padding, options.boundariesElement, data.positionFixed);

var placement = data.placement.split('-')[0];
var placementOpposite = getOppositePlacement(placement);
var variation = data.placement.split('-')[1] || '';

var flipOrder = [];

switch (options.behavior) {
  case BEHAVIORS.FLIP:
    flipOrder = [placement, placementOpposite];
    break;
  case BEHAVIORS.CLOCKWISE:
    flipOrder = clockwise(placement);
    break;
  case BEHAVIORS.COUNTERCLOCKWISE:
    flipOrder = clockwise(placement, true);
    break;
  default:
    flipOrder = options.behavior;
}

flipOrder.forEach(function (step, index) {
  if (placement !== step || flipOrder.length === index + 1) {
    return data;
  }

  placement = data.placement.split('-')[0];
  placementOpposite = getOppositePlacement(placement);

  var popperOffsets = data.offsets.popper;
  var refOffsets = data.offsets.reference;

  // using floor because the reference offsets may contain decimals we are not going to consider here
  var floor = Math.floor;
  var overlapsRef = placement === 'left' && floor(popperOffsets.right) > floor(refOffsets.left) || placement === 'right' && floor(popperOffsets.left) < floor(refOffsets.right) || placement === 'top' && floor(popperOffsets.bottom) > floor(refOffsets.top) || placement === 'bottom' && floor(popperOffsets.top) < floor(refOffsets.bottom);

  var overflowsLeft = floor(popperOffsets.left) < floor(boundaries.left);
  var overflowsRight = floor(popperOffsets.right) > floor(boundaries.right);
  var overflowsTop = floor(popperOffsets.top) < floor(boundaries.top);
  var overflowsBottom = floor(popperOffsets.bottom) > floor(boundaries.bottom);

  var overflowsBoundaries = placement === 'left' && overflowsLeft || placement === 'right' && overflowsRight || placement === 'top' && overflowsTop || placement === 'bottom' && overflowsBottom;

  // flip the variation if required
  var isVertical = ['top', 'bottom'].indexOf(placement) !== -1;
  var flippedVariation = !!options.flipVariations && (isVertical && variation === 'start' && overflowsLeft || isVertical && variation === 'end' && overflowsRight || !isVertical && variation === 'start' && overflowsTop || !isVertical && variation === 'end' && overflowsBottom);

  if (overlapsRef || overflowsBoundaries || flippedVariation) {
    // this boolean to detect any flip loop
    data.flipped = true;

    if (overlapsRef || overflowsBoundaries) {
      placement = flipOrder[index + 1];
    }

    if (flippedVariation) {
      variation = getOppositeVariation(variation);
    }

    data.placement = placement + (variation ? '-' + variation : '');

    // this object contains `position`, we want to preserve it along with
    // any additional property we may add in the future
    data.offsets.popper = _extends({}, data.offsets.popper, getPopperOffsets(data.instance.popper, data.offsets.reference, data.placement));

    data = runModifiers(data.instance.modifiers, data, 'flip');
  }
});
return data;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function keepTogether(data) {

var _data$offsets = data.offsets,
    popper = _data$offsets.popper,
    reference = _data$offsets.reference;

var placement = data.placement.split('-')[0];
var floor = Math.floor;
var isVertical = ['top', 'bottom'].indexOf(placement) !== -1;
var side = isVertical ? 'right' : 'bottom';
var opSide = isVertical ? 'left' : 'top';
var measurement = isVertical ? 'width' : 'height';

if (popper[side] < floor(reference[opSide])) {
  data.offsets.popper[opSide] = floor(reference[opSide]) - popper[measurement];
}
if (popper[opSide] > floor(reference[side])) {
  data.offsets.popper[opSide] = floor(reference[side]);
}

return data;

}

/**

* Converts a string containing value + unit into a px value number
* @function
* @memberof {modifiers~offset}
* @private
* @argument {String} str - Value + unit string
* @argument {String} measurement - `height` or `width`
* @argument {Object} popperOffsets
* @argument {Object} referenceOffsets
* @returns {Number|String}
* Value in pixels, or original string if no values were extracted
*/

function toValue(str, measurement, popperOffsets, referenceOffsets) {

// separate value from unit
var split = str.match(/((?:\-|\+)?\d*\.?\d*)(.*)/);
var value = +split[1];
var unit = split[2];

// If it's not a number it's an operator, I guess
if (!value) {
  return str;
}

if (unit.indexOf('%') === 0) {
  var element = void 0;
  switch (unit) {
    case '%p':
      element = popperOffsets;
      break;
    case '%':
    case '%r':
    default:
      element = referenceOffsets;
  }

  var rect = getClientRect(element);
  return rect[measurement] / 100 * value;
} else if (unit === 'vh' || unit === 'vw') {
  // if is a vh or vw, we calculate the size based on the viewport
  var size = void 0;
  if (unit === 'vh') {
    size = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
  } else {
    size = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
  }
  return size / 100 * value;
} else {
  // if is an explicit pixel unit, we get rid of the unit and keep the value
  // if is an implicit unit, it's px, and we return just the value
  return value;
}

}

/**

* Parse an `offset` string to extrapolate `x` and `y` numeric offsets.
* @function
* @memberof {modifiers~offset}
* @private
* @argument {String} offset
* @argument {Object} popperOffsets
* @argument {Object} referenceOffsets
* @argument {String} basePlacement
* @returns {Array} a two cells array with x and y offsets in numbers
*/

function parseOffset(offset, popperOffsets, referenceOffsets, basePlacement) {

var offsets = [0, 0];

// Use height if placement is left or right and index is 0 otherwise use width
// in this way the first offset will use an axis and the second one
// will use the other one
var useHeight = ['right', 'left'].indexOf(basePlacement) !== -1;

// Split the offset string to obtain a list of values and operands
// The regex addresses values with the plus or minus sign in front (+10, -20, etc)
var fragments = offset.split(/(\+|\-)/).map(function (frag) {
  return frag.trim();
});

// Detect if the offset string contains a pair of values or a single one
// they could be separated by comma or space
var divider = fragments.indexOf(find(fragments, function (frag) {
  return frag.search(/,|\s/) !== -1;
}));

if (fragments[divider] && fragments[divider].indexOf(',') === -1) {
  console.warn('Offsets separated by white space(s) are deprecated, use a comma (,) instead.');
}

// If divider is found, we divide the list of values and operands to divide
// them by ofset X and Y.
var splitRegex = /\s*,\s*|\s+/;
var ops = divider !== -1 ? [fragments.slice(0, divider).concat([fragments[divider].split(splitRegex)[0]]), [fragments[divider].split(splitRegex)[1]].concat(fragments.slice(divider + 1))] : [fragments];

// Convert the values with units to absolute pixels to allow our computations
ops = ops.map(function (op, index) {
  // Most of the units rely on the orientation of the popper
  var measurement = (index === 1 ? !useHeight : useHeight) ? 'height' : 'width';
  var mergeWithPrevious = false;
  return op
  // This aggregates any `+` or `-` sign that aren't considered operators
  // e.g.: 10 + +5 => [10, +, +5]
  .reduce(function (a, b) {
    if (a[a.length - 1] === '' && ['+', '-'].indexOf(b) !== -1) {
      a[a.length - 1] = b;
      mergeWithPrevious = true;
      return a;
    } else if (mergeWithPrevious) {
      a[a.length - 1] += b;
      mergeWithPrevious = false;
      return a;
    } else {
      return a.concat(b);
    }
  }, [])
  // Here we convert the string values into number values (in px)
  .map(function (str) {
    return toValue(str, measurement, popperOffsets, referenceOffsets);
  });
});

// Loop trough the offsets arrays and execute the operations
ops.forEach(function (op, index) {
  op.forEach(function (frag, index2) {
    if (isNumeric(frag)) {
      offsets[index] += frag * (op[index2 - 1] === '-' ? -1 : 1);
    }
  });
});
return offsets;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @argument {Number|String} options.offset=0
* The offset value as described in the modifier description
* @returns {Object} The data object, properly modified
*/

function offset(data, _ref) {

var offset = _ref.offset;
var placement = data.placement,
    _data$offsets = data.offsets,
    popper = _data$offsets.popper,
    reference = _data$offsets.reference;

var basePlacement = placement.split('-')[0];

var offsets = void 0;
if (isNumeric(+offset)) {
  offsets = [+offset, 0];
} else {
  offsets = parseOffset(offset, popper, reference, basePlacement);
}

if (basePlacement === 'left') {
  popper.top += offsets[0];
  popper.left -= offsets[1];
} else if (basePlacement === 'right') {
  popper.top += offsets[0];
  popper.left += offsets[1];
} else if (basePlacement === 'top') {
  popper.left += offsets[0];
  popper.top -= offsets[1];
} else if (basePlacement === 'bottom') {
  popper.left += offsets[0];
  popper.top += offsets[1];
}

data.popper = popper;
return data;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by `update` method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function preventOverflow(data, options) {

var boundariesElement = options.boundariesElement || getOffsetParent(data.instance.popper);

// If offsetParent is the reference element, we really want to
// go one step up and use the next offsetParent as reference to
// avoid to make this modifier completely useless and look like broken
if (data.instance.reference === boundariesElement) {
  boundariesElement = getOffsetParent(boundariesElement);
}

// NOTE: DOM access here
// resets the popper's position so that the document size can be calculated excluding
// the size of the popper element itself
var transformProp = getSupportedPropertyName('transform');
var popperStyles = data.instance.popper.style; // assignment to help minification
var top = popperStyles.top,
    left = popperStyles.left,
    transform = popperStyles[transformProp];

popperStyles.top = '';
popperStyles.left = '';
popperStyles[transformProp] = '';

var boundaries = getBoundaries(data.instance.popper, data.instance.reference, options.padding, boundariesElement, data.positionFixed);

// NOTE: DOM access here
// restores the original style properties after the offsets have been computed
popperStyles.top = top;
popperStyles.left = left;
popperStyles[transformProp] = transform;

options.boundaries = boundaries;

var order = options.priority;
var popper = data.offsets.popper;

var check = {
  primary: function primary(placement) {
    var value = popper[placement];
    if (popper[placement] < boundaries[placement] && !options.escapeWithReference) {
      value = Math.max(popper[placement], boundaries[placement]);
    }
    return defineProperty({}, placement, value);
  },
  secondary: function secondary(placement) {
    var mainSide = placement === 'right' ? 'left' : 'top';
    var value = popper[mainSide];
    if (popper[placement] > boundaries[placement] && !options.escapeWithReference) {
      value = Math.min(popper[mainSide], boundaries[placement] - (placement === 'right' ? popper.width : popper.height));
    }
    return defineProperty({}, mainSide, value);
  }
};

order.forEach(function (placement) {
  var side = ['left', 'top'].indexOf(placement) !== -1 ? 'primary' : 'secondary';
  popper = _extends({}, popper, check[side](placement));
});

data.offsets.popper = popper;

return data;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by `update` method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function shift(data) {

var placement = data.placement;
var basePlacement = placement.split('-')[0];
var shiftvariation = placement.split('-')[1];

// if shift shiftvariation is specified, run the modifier
if (shiftvariation) {
  var _data$offsets = data.offsets,
      reference = _data$offsets.reference,
      popper = _data$offsets.popper;

  var isVertical = ['bottom', 'top'].indexOf(basePlacement) !== -1;
  var side = isVertical ? 'left' : 'top';
  var measurement = isVertical ? 'width' : 'height';

  var shiftOffsets = {
    start: defineProperty({}, side, reference[side]),
    end: defineProperty({}, side, reference[side] + reference[measurement] - popper[measurement])
  };

  data.offsets.popper = _extends({}, popper, shiftOffsets[shiftvariation]);
}

return data;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by update method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function hide(data) {

if (!isModifierRequired(data.instance.modifiers, 'hide', 'preventOverflow')) {
  return data;
}

var refRect = data.offsets.reference;
var bound = find(data.instance.modifiers, function (modifier) {
  return modifier.name === 'preventOverflow';
}).boundaries;

if (refRect.bottom < bound.top || refRect.left > bound.right || refRect.top > bound.bottom || refRect.right < bound.left) {
  // Avoid unnecessary DOM access if visibility hasn't changed
  if (data.hide === true) {
    return data;
  }

  data.hide = true;
  data.attributes['x-out-of-boundaries'] = '';
} else {
  // Avoid unnecessary DOM access if visibility hasn't changed
  if (data.hide === false) {
    return data;
  }

  data.hide = false;
  data.attributes['x-out-of-boundaries'] = false;
}

return data;

}

/**

* @function
* @memberof Modifiers
* @argument {Object} data - The data object generated by `update` method
* @argument {Object} options - Modifiers configuration and options
* @returns {Object} The data object, properly modified
*/

function inner(data) {

var placement = data.placement;
var basePlacement = placement.split('-')[0];
var _data$offsets = data.offsets,
    popper = _data$offsets.popper,
    reference = _data$offsets.reference;

var isHoriz = ['left', 'right'].indexOf(basePlacement) !== -1;

var subtractLength = ['top', 'left'].indexOf(basePlacement) === -1;

popper[isHoriz ? 'left' : 'top'] = reference[basePlacement] - (subtractLength ? popper[isHoriz ? 'width' : 'height'] : 0);

data.placement = getOppositePlacement(placement);
data.offsets.popper = getClientRect(popper);

return data;

}

/**

* Modifier function, each modifier can have a function of this type assigned
* to its `fn` property.<br />
* These functions will be called on each update, this means that you must
* make sure they are performant enough to avoid performance bottlenecks.
*
* @function ModifierFn
* @argument {dataObject} data - The data object generated by `update` method
* @argument {Object} options - Modifiers configuration and options
* @returns {dataObject} The data object, properly modified
*/

/**

* Modifiers are plugins used to alter the behavior of your poppers.<br />
* Popper.js uses a set of 9 modifiers to provide all the basic functionalities
* needed by the library.
*
* Usually you don't want to override the `order`, `fn` and `onLoad` props.
* All the other properties are configurations that could be tweaked.
* @namespace modifiers
*/

var modifiers = {

/**
 * Modifier used to shift the popper on the start or end of its reference
 * element.<br />
 * It will read the variation of the `placement` property.<br />
 * It can be one either `-end` or `-start`.
 * @memberof modifiers
 * @inner
 */
shift: {
  /** @prop {number} order=100 - Index used to define the order of execution */
  order: 100,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: shift
},

/**
 * The `offset` modifier can shift your popper on both its axis.
 *
 * It accepts the following units:
 * - `px` or unit-less, interpreted as pixels
 * - `%` or `%r`, percentage relative to the length of the reference element
 * - `%p`, percentage relative to the length of the popper element
 * - `vw`, CSS viewport width unit
 * - `vh`, CSS viewport height unit
 *
 * For length is intended the main axis relative to the placement of the popper.<br />
 * This means that if the placement is `top` or `bottom`, the length will be the
 * `width`. In case of `left` or `right`, it will be the `height`.
 *
 * You can provide a single value (as `Number` or `String`), or a pair of values
 * as `String` divided by a comma or one (or more) white spaces.<br />
 * The latter is a deprecated method because it leads to confusion and will be
 * removed in v2.<br />
 * Additionally, it accepts additions and subtractions between different units.
 * Note that multiplications and divisions aren't supported.
 *
 * Valid examples are:
 * ```
 * 10
 * '10%'
 * '10, 10'
 * '10%, 10'
 * '10 + 10%'
 * '10 - 5vh + 3%'
 * '-10px + 5vh, 5px - 6%'
 * ```
 * > **NB**: If you desire to apply offsets to your poppers in a way that may make them overlap
 * > with their reference element, unfortunately, you will have to disable the `flip` modifier.
 * > You can read more on this at this [issue](https://github.com/FezVrasta/popper.js/issues/373).
 *
 * @memberof modifiers
 * @inner
 */
offset: {
  /** @prop {number} order=200 - Index used to define the order of execution */
  order: 200,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: offset,
  /** @prop {Number|String} offset=0
   * The offset value as described in the modifier description
   */
  offset: 0
},

/**
 * Modifier used to prevent the popper from being positioned outside the boundary.
 *
 * A scenario exists where the reference itself is not within the boundaries.<br />
 * We can say it has "escaped the boundaries" — or just "escaped".<br />
 * In this case we need to decide whether the popper should either:
 *
 * - detach from the reference and remain "trapped" in the boundaries, or
 * - if it should ignore the boundary and "escape with its reference"
 *
 * When `escapeWithReference` is set to`true` and reference is completely
 * outside its boundaries, the popper will overflow (or completely leave)
 * the boundaries in order to remain attached to the edge of the reference.
 *
 * @memberof modifiers
 * @inner
 */
preventOverflow: {
  /** @prop {number} order=300 - Index used to define the order of execution */
  order: 300,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: preventOverflow,
  /**
   * @prop {Array} [priority=['left','right','top','bottom']]
   * Popper will try to prevent overflow following these priorities by default,
   * then, it could overflow on the left and on top of the `boundariesElement`
   */
  priority: ['left', 'right', 'top', 'bottom'],
  /**
   * @prop {number} padding=5
   * Amount of pixel used to define a minimum distance between the boundaries
   * and the popper. This makes sure the popper always has a little padding
   * between the edges of its container
   */
  padding: 5,
  /**
   * @prop {String|HTMLElement} boundariesElement='scrollParent'
   * Boundaries used by the modifier. Can be `scrollParent`, `window`,
   * `viewport` or any DOM element.
   */
  boundariesElement: 'scrollParent'
},

/**
 * Modifier used to make sure the reference and its popper stay near each other
 * without leaving any gap between the two. Especially useful when the arrow is
 * enabled and you want to ensure that it points to its reference element.
 * It cares only about the first axis. You can still have poppers with margin
 * between the popper and its reference element.
 * @memberof modifiers
 * @inner
 */
keepTogether: {
  /** @prop {number} order=400 - Index used to define the order of execution */
  order: 400,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: keepTogether
},

/**
 * This modifier is used to move the `arrowElement` of the popper to make
 * sure it is positioned between the reference element and its popper element.
 * It will read the outer size of the `arrowElement` node to detect how many
 * pixels of conjunction are needed.
 *
 * It has no effect if no `arrowElement` is provided.
 * @memberof modifiers
 * @inner
 */
arrow: {
  /** @prop {number} order=500 - Index used to define the order of execution */
  order: 500,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: arrow,
  /** @prop {String|HTMLElement} element='[x-arrow]' - Selector or node used as arrow */
  element: '[x-arrow]'
},

/**
 * Modifier used to flip the popper's placement when it starts to overlap its
 * reference element.
 *
 * Requires the `preventOverflow` modifier before it in order to work.
 *
 * **NOTE:** this modifier will interrupt the current update cycle and will
 * restart it if it detects the need to flip the placement.
 * @memberof modifiers
 * @inner
 */
flip: {
  /** @prop {number} order=600 - Index used to define the order of execution */
  order: 600,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: flip,
  /**
   * @prop {String|Array} behavior='flip'
   * The behavior used to change the popper's placement. It can be one of
   * `flip`, `clockwise`, `counterclockwise` or an array with a list of valid
   * placements (with optional variations)
   */
  behavior: 'flip',
  /**
   * @prop {number} padding=5
   * The popper will flip if it hits the edges of the `boundariesElement`
   */
  padding: 5,
  /**
   * @prop {String|HTMLElement} boundariesElement='viewport'
   * The element which will define the boundaries of the popper position.
   * The popper will never be placed outside of the defined boundaries
   * (except if `keepTogether` is enabled)
   */
  boundariesElement: 'viewport'
},

/**
 * Modifier used to make the popper flow toward the inner of the reference element.
 * By default, when this modifier is disabled, the popper will be placed outside
 * the reference element.
 * @memberof modifiers
 * @inner
 */
inner: {
  /** @prop {number} order=700 - Index used to define the order of execution */
  order: 700,
  /** @prop {Boolean} enabled=false - Whether the modifier is enabled or not */
  enabled: false,
  /** @prop {ModifierFn} */
  fn: inner
},

/**
 * Modifier used to hide the popper when its reference element is outside of the
 * popper boundaries. It will set a `x-out-of-boundaries` attribute which can
 * be used to hide with a CSS selector the popper when its reference is
 * out of boundaries.
 *
 * Requires the `preventOverflow` modifier before it in order to work.
 * @memberof modifiers
 * @inner
 */
hide: {
  /** @prop {number} order=800 - Index used to define the order of execution */
  order: 800,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: hide
},

/**
 * Computes the style that will be applied to the popper element to gets
 * properly positioned.
 *
 * Note that this modifier will not touch the DOM, it just prepares the styles
 * so that `applyStyle` modifier can apply it. This separation is useful
 * in case you need to replace `applyStyle` with a custom implementation.
 *
 * This modifier has `850` as `order` value to maintain backward compatibility
 * with previous versions of Popper.js. Expect the modifiers ordering method
 * to change in future major versions of the library.
 *
 * @memberof modifiers
 * @inner
 */
computeStyle: {
  /** @prop {number} order=850 - Index used to define the order of execution */
  order: 850,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: computeStyle,
  /**
   * @prop {Boolean} gpuAcceleration=true
   * If true, it uses the CSS 3D transformation to position the popper.
   * Otherwise, it will use the `top` and `left` properties
   */
  gpuAcceleration: true,
  /**
   * @prop {string} [x='bottom']
   * Where to anchor the X axis (`bottom` or `top`). AKA X offset origin.
   * Change this if your popper should grow in a direction different from `bottom`
   */
  x: 'bottom',
  /**
   * @prop {string} [x='left']
   * Where to anchor the Y axis (`left` or `right`). AKA Y offset origin.
   * Change this if your popper should grow in a direction different from `right`
   */
  y: 'right'
},

/**
 * Applies the computed styles to the popper element.
 *
 * All the DOM manipulations are limited to this modifier. This is useful in case
 * you want to integrate Popper.js inside a framework or view library and you
 * want to delegate all the DOM manipulations to it.
 *
 * Note that if you disable this modifier, you must make sure the popper element
 * has its position set to `absolute` before Popper.js can do its work!
 *
 * Just disable this modifier and define your own to achieve the desired effect.
 *
 * @memberof modifiers
 * @inner
 */
applyStyle: {
  /** @prop {number} order=900 - Index used to define the order of execution */
  order: 900,
  /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
  enabled: true,
  /** @prop {ModifierFn} */
  fn: applyStyle,
  /** @prop {Function} */
  onLoad: applyStyleOnLoad,
  /**
   * @deprecated since version 1.10.0, the property moved to `computeStyle` modifier
   * @prop {Boolean} gpuAcceleration=true
   * If true, it uses the CSS 3D transformation to position the popper.
   * Otherwise, it will use the `top` and `left` properties
   */
  gpuAcceleration: undefined
}

};

/**

* The `dataObject` is an object containing all the information used by Popper.js.
* This object is passed to modifiers and to the `onCreate` and `onUpdate` callbacks.
* @name dataObject
* @property {Object} data.instance The Popper.js instance
* @property {String} data.placement Placement applied to popper
* @property {String} data.originalPlacement Placement originally defined on init
* @property {Boolean} data.flipped True if popper has been flipped by flip modifier
* @property {Boolean} data.hide True if the reference element is out of boundaries, useful to know when to hide the popper
* @property {HTMLElement} data.arrowElement Node used as arrow by arrow modifier
* @property {Object} data.styles Any CSS property defined here will be applied to the popper. It expects the JavaScript nomenclature (eg. `marginBottom`)
* @property {Object} data.arrowStyles Any CSS property defined here will be applied to the popper arrow. It expects the JavaScript nomenclature (eg. `marginBottom`)
* @property {Object} data.boundaries Offsets of the popper boundaries
* @property {Object} data.offsets The measurements of popper, reference and arrow elements
* @property {Object} data.offsets.popper `top`, `left`, `width`, `height` values
* @property {Object} data.offsets.reference `top`, `left`, `width`, `height` values
* @property {Object} data.offsets.arrow] `top` and `left` offsets, only one of them will be different from 0
*/

/**

* Default options provided to Popper.js constructor.<br />
* These can be overridden using the `options` argument of Popper.js.<br />
* To override an option, simply pass an object with the same
* structure of the `options` object, as the 3rd argument. For example:
* ```
* new Popper(ref, pop, {
*   modifiers: {
*     preventOverflow: { enabled: false }
*   }
* })
* ```
* @type {Object}
* @static
* @memberof Popper
*/

var Defaults = {

/**
 * Popper's placement.
 * @prop {Popper.placements} placement='bottom'
 */
placement: 'bottom',

/**
 * Set this to true if you want popper to position it self in 'fixed' mode
 * @prop {Boolean} positionFixed=false
 */
positionFixed: false,

/**
 * Whether events (resize, scroll) are initially enabled.
 * @prop {Boolean} eventsEnabled=true
 */
eventsEnabled: true,

/**
 * Set to true if you want to automatically remove the popper when
 * you call the `destroy` method.
 * @prop {Boolean} removeOnDestroy=false
 */
removeOnDestroy: false,

/**
 * Callback called when the popper is created.<br />
 * By default, it is set to no-op.<br />
 * Access Popper.js instance with `data.instance`.
 * @prop {onCreate}
 */
onCreate: function onCreate() {},

/**
 * Callback called when the popper is updated. This callback is not called
 * on the initialization/creation of the popper, but only on subsequent
 * updates.<br />
 * By default, it is set to no-op.<br />
 * Access Popper.js instance with `data.instance`.
 * @prop {onUpdate}
 */
onUpdate: function onUpdate() {},

/**
 * List of modifiers used to modify the offsets before they are applied to the popper.
 * They provide most of the functionalities of Popper.js.
 * @prop {modifiers}
 */
modifiers: modifiers

};

/**

* @callback onCreate
* @param {dataObject} data
*/

/**

* @callback onUpdate
* @param {dataObject} data
*/

// Utils // Methods var Popper = function () {

/**
 * Creates a new Popper.js instance.
 * @class Popper
 * @param {HTMLElement|referenceObject} reference - The reference element used to position the popper
 * @param {HTMLElement} popper - The HTML element used as the popper
 * @param {Object} options - Your custom options to override the ones defined in [Defaults](#defaults)
 * @return {Object} instance - The generated Popper.js instance
 */
function Popper(reference, popper) {
  var _this = this;

  var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
  classCallCheck(this, Popper);

  this.scheduleUpdate = function () {
    return requestAnimationFrame(_this.update);
  };

  // make update() debounced, so that it only runs at most once-per-tick
  this.update = debounce(this.update.bind(this));

  // with {} we create a new object with the options inside it
  this.options = _extends({}, Popper.Defaults, options);

  // init state
  this.state = {
    isDestroyed: false,
    isCreated: false,
    scrollParents: []
  };

  // get reference and popper elements (allow jQuery wrappers)
  this.reference = reference && reference.jquery ? reference[0] : reference;
  this.popper = popper && popper.jquery ? popper[0] : popper;

  // Deep merge modifiers options
  this.options.modifiers = {};
  Object.keys(_extends({}, Popper.Defaults.modifiers, options.modifiers)).forEach(function (name) {
    _this.options.modifiers[name] = _extends({}, Popper.Defaults.modifiers[name] || {}, options.modifiers ? options.modifiers[name] : {});
  });

  // Refactoring modifiers' list (Object => Array)
  this.modifiers = Object.keys(this.options.modifiers).map(function (name) {
    return _extends({
      name: name
    }, _this.options.modifiers[name]);
  })
  // sort the modifiers by order
  .sort(function (a, b) {
    return a.order - b.order;
  });

  // modifiers have the ability to execute arbitrary code when Popper.js get inited
  // such code is executed in the same order of its modifier
  // they could add new properties to their options configuration
  // BE AWARE: don't add options to `options.modifiers.name` but to `modifierOptions`!
  this.modifiers.forEach(function (modifierOptions) {
    if (modifierOptions.enabled && isFunction(modifierOptions.onLoad)) {
      modifierOptions.onLoad(_this.reference, _this.popper, _this.options, modifierOptions, _this.state);
    }
  });

  // fire the first update to position the popper in the right place
  this.update();

  var eventsEnabled = this.options.eventsEnabled;
  if (eventsEnabled) {
    // setup event listeners, they will take care of update the position in specific situations
    this.enableEventListeners();
  }

  this.state.eventsEnabled = eventsEnabled;
}

// We can't use class properties because they don't get listed in the
// class prototype and break stuff like Sinon stubs

createClass(Popper, [{
  key: 'update',
  value: function update$$1() {
    return update.call(this);
  }
}, {
  key: 'destroy',
  value: function destroy$$1() {
    return destroy.call(this);
  }
}, {
  key: 'enableEventListeners',
  value: function enableEventListeners$$1() {
    return enableEventListeners.call(this);
  }
}, {
  key: 'disableEventListeners',
  value: function disableEventListeners$$1() {
    return disableEventListeners.call(this);
  }

  /**
   * Schedules an update. It will run on the next UI update available.
   * @method scheduleUpdate
   * @memberof Popper
   */

  /**
   * Collection of utilities useful when writing custom modifiers.
   * Starting from version 1.7, this method is available only if you
   * include `popper-utils.js` before `popper.js`.
   *
   * **DEPRECATION**: This way to access PopperUtils is deprecated
   * and will be removed in v2! Use the PopperUtils module directly instead.
   * Due to the high instability of the methods contained in Utils, we can't
   * guarantee them to follow semver. Use them at your own risk!
   * @static
   * @private
   * @type {Object}
   * @deprecated since version 1.8
   * @member Utils
   * @memberof Popper
   */

}]);
return Popper;

}();

/**

* The `referenceObject` is an object that provides an interface compatible with Popper.js
* and lets you use it as replacement of a real DOM node.<br />
* You can use this method to position a popper relatively to a set of coordinates
* in case you don't have a DOM node to use as reference.
*
* ```
* new Popper(referenceObject, popperNode);
* ```
*
* NB: This feature isn't supported in Internet Explorer 10.
* @name referenceObject
* @property {Function} data.getBoundingClientRect
* A function that returns a set of coordinates compatible with the native `getBoundingClientRect` method.
* @property {number} data.clientWidth
* An ES6 getter that will return the width of the virtual reference element.
* @property {number} data.clientHeight
* An ES6 getter that will return the height of the virtual reference element.
*/

Popper.Utils = (typeof window !== 'undefined' ? window : global).PopperUtils; Popper.placements = placements; Popper.Defaults = Defaults;

return Popper;

}))); //# sourceMappingURL=popper.js.map