bootstrap-modal-form/src/js/bootstrap/mdb-prefix/dropdown.js

Bootstrap modal forms are displayed-on-action pop-up forms that are used for gathering data from website visitors, to register or log users.

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v5.1.3): dropdown.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
 * --------------------------------------------------------------------------
 */

import * as Popper from '@popperjs/core';

import {
  defineJQueryPlugin,
  getElement,
  getElementFromSelector,
  getNextActiveElement,
  isDisabled,
  isElement,
  isRTL,
  isVisible,
  noop,
  typeCheckConfig,
} from './util/index';
import EventHandler from './dom/event-handler';
import Manipulator from './dom/manipulator';
import SelectorEngine from './dom/selector-engine';
import BaseComponent from './base-component';

/**
 * ------------------------------------------------------------------------
 * Constants
 * ------------------------------------------------------------------------
 */

const NAME = 'dropdown';
const DATA_KEY = 'bs.dropdown';
const EVENT_KEY = `.${DATA_KEY}`;
const DATA_API_KEY = '.data-api';

const ESCAPE_KEY = 'Escape';
const SPACE_KEY = 'Space';
const TAB_KEY = 'Tab';
const ARROW_UP_KEY = 'ArrowUp';
const ARROW_DOWN_KEY = 'ArrowDown';
const RIGHT_MOUSE_BUTTON = 2; // MouseEvent.button value for the secondary button, usually the right button

const REGEXP_KEYDOWN = new RegExp(`${ARROW_UP_KEY}|${ARROW_DOWN_KEY}|${ESCAPE_KEY}`);

const EVENT_HIDE = `hide${EVENT_KEY}`;
const EVENT_HIDDEN = `hidden${EVENT_KEY}`;
const EVENT_SHOW = `show${EVENT_KEY}`;
const EVENT_SHOWN = `shown${EVENT_KEY}`;
const EVENT_CLICK_DATA_API = `click${EVENT_KEY}${DATA_API_KEY}`;
const EVENT_KEYDOWN_DATA_API = `keydown${EVENT_KEY}${DATA_API_KEY}`;
const EVENT_KEYUP_DATA_API = `keyup${EVENT_KEY}${DATA_API_KEY}`;

const CLASS_NAME_SHOW = 'show';
const CLASS_NAME_DROPUP = 'dropup';
const CLASS_NAME_DROPEND = 'dropend';
const CLASS_NAME_DROPSTART = 'dropstart';
const CLASS_NAME_NAVBAR = 'navbar';

const SELECTOR_DATA_TOGGLE = '[data-mdb-toggle="dropdown"]';
const SELECTOR_MENU = '.dropdown-menu';
const SELECTOR_NAVBAR_NAV = '.navbar-nav';
const SELECTOR_VISIBLE_ITEMS = '.dropdown-menu .dropdown-item:not(.disabled):not(:disabled)';

const PLACEMENT_TOP = isRTL() ? 'top-end' : 'top-start';
const PLACEMENT_TOPEND = isRTL() ? 'top-start' : 'top-end';
const PLACEMENT_BOTTOM = isRTL() ? 'bottom-end' : 'bottom-start';
const PLACEMENT_BOTTOMEND = isRTL() ? 'bottom-start' : 'bottom-end';
const PLACEMENT_RIGHT = isRTL() ? 'left-start' : 'right-start';
const PLACEMENT_LEFT = isRTL() ? 'right-start' : 'left-start';

const Default = {
  offset: [0, 2],
  boundary: 'clippingParents',
  reference: 'toggle',
  display: 'dynamic',
  popperConfig: null,
  autoClose: true,
};

const DefaultType = {
  offset: '(array|string|function)',
  boundary: '(string|element)',
  reference: '(string|element|object)',
  display: 'string',
  popperConfig: '(null|object|function)',
  autoClose: '(boolean|string)',
};

/**
 * ------------------------------------------------------------------------
 * Class Definition
 * ------------------------------------------------------------------------
 */

class Dropdown extends BaseComponent {
  constructor(element, config) {
    super(element);

    this._popper = null;
    this._config = this._getConfig(config);
    this._menu = this._getMenuElement();
    this._inNavbar = this._detectNavbar();
  }

  // Getters

  static get Default() {
    return Default;
  }

  static get DefaultType() {
    return DefaultType;
  }

  static get NAME() {
    return NAME;
  }

  // Public

  toggle() {
    return this._isShown() ? this.hide() : this.show();
  }

  show() {
    if (isDisabled(this._element) || this._isShown(this._menu)) {
      return;
    }

    const relatedTarget = {
      relatedTarget: this._element,
    };

    const showEvent = EventHandler.trigger(this._element, EVENT_SHOW, relatedTarget);

    if (showEvent.defaultPrevented) {
      return;
    }

    const parent = Dropdown.getParentFromElement(this._element);
    // Totally disable Popper for Dropdowns in Navbar
    if (this._inNavbar) {
      Manipulator.setDataAttribute(this._menu, 'popper', 'none');
    } else {
      this._createPopper(parent);
    }

    // If this is a touch-enabled device we add extra
    // empty mouseover listeners to the body's immediate children;
    // only needed because of broken event delegation on iOS
    // https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html
    if ('ontouchstart' in document.documentElement && !parent.closest(SELECTOR_NAVBAR_NAV)) {
      []
        .concat(...document.body.children)
        .forEach((elem) => EventHandler.on(elem, 'mouseover', noop));
    }

    this._element.focus();
    this._element.setAttribute('aria-expanded', true);

    this._menu.classList.add(CLASS_NAME_SHOW);
    this._element.classList.add(CLASS_NAME_SHOW);
    EventHandler.trigger(this._element, EVENT_SHOWN, relatedTarget);
  }

  hide() {
    if (isDisabled(this._element) || !this._isShown(this._menu)) {
      return;
    }

    const relatedTarget = {
      relatedTarget: this._element,
    };

    this._completeHide(relatedTarget);
  }

  dispose() {
    if (this._popper) {
      this._popper.destroy();
    }

    super.dispose();
  }

  update() {
    this._inNavbar = this._detectNavbar();
    if (this._popper) {
      this._popper.update();
    }
  }

  // Private

  _completeHide(relatedTarget) {
    const hideEvent = EventHandler.trigger(this._element, EVENT_HIDE, relatedTarget);
    if (hideEvent.defaultPrevented) {
      return;
    }

    // If this is a touch-enabled device we remove the extra
    // empty mouseover listeners we added for iOS support
    if ('ontouchstart' in document.documentElement) {
      []
        .concat(...document.body.children)
        .forEach((elem) => EventHandler.off(elem, 'mouseover', noop));
    }

    if (this._popper) {
      this._popper.destroy();
    }

    this._menu.classList.remove(CLASS_NAME_SHOW);
    this._element.classList.remove(CLASS_NAME_SHOW);
    this._element.setAttribute('aria-expanded', 'false');
    Manipulator.removeDataAttribute(this._menu, 'popper');
    EventHandler.trigger(this._element, EVENT_HIDDEN, relatedTarget);
  }

  _getConfig(config) {
    config = {
      ...this.constructor.Default,
      ...Manipulator.getDataAttributes(this._element),
      ...config,
    };

    typeCheckConfig(NAME, config, this.constructor.DefaultType);

    if (
      typeof config.reference === 'object' &&
      !isElement(config.reference) &&
      typeof config.reference.getBoundingClientRect !== 'function'
    ) {
      // Popper virtual elements require a getBoundingClientRect method
      throw new TypeError(
        `${NAME.toUpperCase()}: Option "reference" provided type "object" without a required "getBoundingClientRect" method.`
      );
    }

    return config;
  }

  _createPopper(parent) {
    if (typeof Popper === 'undefined') {
      throw new TypeError("Bootstrap's dropdowns require Popper (https://popper.js.org)");
    }

    let referenceElement = this._element;

    if (this._config.reference === 'parent') {
      referenceElement = parent;
    } else if (isElement(this._config.reference)) {
      referenceElement = getElement(this._config.reference);
    } else if (typeof this._config.reference === 'object') {
      referenceElement = this._config.reference;
    }

    const popperConfig = this._getPopperConfig();
    const isDisplayStatic = popperConfig.modifiers.find(
      (modifier) => modifier.name === 'applyStyles' && modifier.enabled === false
    );

    this._popper = Popper.createPopper(referenceElement, this._menu, popperConfig);

    if (isDisplayStatic) {
      Manipulator.setDataAttribute(this._menu, 'popper', 'static');
    }
  }

  _isShown(element = this._element) {
    return element.classList.contains(CLASS_NAME_SHOW);
  }

  _getMenuElement() {
    return SelectorEngine.next(this._element, SELECTOR_MENU)[0];
  }

  _getPlacement() {
    const parentDropdown = this._element.parentNode;

    if (parentDropdown.classList.contains(CLASS_NAME_DROPEND)) {
      return PLACEMENT_RIGHT;
    }

    if (parentDropdown.classList.contains(CLASS_NAME_DROPSTART)) {
      return PLACEMENT_LEFT;
    }

    // We need to trim the value because custom properties can also include spaces
    const isEnd = getComputedStyle(this._menu).getPropertyValue('--bs-position').trim() === 'end';

    if (parentDropdown.classList.contains(CLASS_NAME_DROPUP)) {
      return isEnd ? PLACEMENT_TOPEND : PLACEMENT_TOP;
    }

    return isEnd ? PLACEMENT_BOTTOMEND : PLACEMENT_BOTTOM;
  }

  _detectNavbar() {
    return this._element.closest(`.${CLASS_NAME_NAVBAR}`) !== null;
  }

  _getOffset() {
    const { offset } = this._config;

    if (typeof offset === 'string') {
      return offset.split(',').map((val) => Number.parseInt(val, 10));
    }

    if (typeof offset === 'function') {
      return (popperData) => offset(popperData, this._element);
    }

    return offset;
  }

  _getPopperConfig() {
    const defaultBsPopperConfig = {
      placement: this._getPlacement(),
      modifiers: [
        {
          name: 'preventOverflow',
          options: {
            boundary: this._config.boundary,
          },
        },
        {
          name: 'offset',
          options: {
            offset: this._getOffset(),
          },
        },
      ],
    };

    // Disable Popper if we have a static display
    if (this._config.display === 'static') {
      defaultBsPopperConfig.modifiers = [
        {
          name: 'applyStyles',
          enabled: false,
        },
      ];
    }

    return {
      ...defaultBsPopperConfig,
      ...(typeof this._config.popperConfig === 'function'
        ? this._config.popperConfig(defaultBsPopperConfig)
        : this._config.popperConfig),
    };
  }

  _selectMenuItem({ key, target }) {
    const items = SelectorEngine.find(SELECTOR_VISIBLE_ITEMS, this._menu).filter(isVisible);

    if (!items.length) {
      return;
    }

    // if target isn't included in items (e.g. when expanding the dropdown)
    // allow cycling to get the last item in case key equals ARROW_UP_KEY
    getNextActiveElement(items, target, key === ARROW_DOWN_KEY, !items.includes(target)).focus();
  }

  // Static

  static jQueryInterface(config) {
    return this.each(function () {
      const data = Dropdown.getOrCreateInstance(this, config);

      if (typeof config !== 'string') {
        return;
      }

      if (typeof data[config] === 'undefined') {
        throw new TypeError(`No method named "${config}"`);
      }

      data[config]();
    });
  }

  static clearMenus(event) {
    if (
      event &&
      (event.button === RIGHT_MOUSE_BUTTON || (event.type === 'keyup' && event.key !== TAB_KEY))
    ) {
      return;
    }

    const toggles = SelectorEngine.find(SELECTOR_DATA_TOGGLE);

    for (let i = 0, len = toggles.length; i < len; i++) {
      const context = Dropdown.getInstance(toggles[i]);
      if (!context || context._config.autoClose === false) {
        continue;
      }

      if (!context._isShown()) {
        continue;
      }

      const relatedTarget = {
        relatedTarget: context._element,
      };

      if (event) {
        const composedPath = event.composedPath();
        const isMenuTarget = composedPath.includes(context._menu);
        if (
          composedPath.includes(context._element) ||
          (context._config.autoClose === 'inside' && !isMenuTarget) ||
          (context._config.autoClose === 'outside' && isMenuTarget)
        ) {
          continue;
        }

        // Tab navigation through the dropdown menu or events from contained inputs shouldn't close the menu
        if (
          context._menu.contains(event.target) &&
          ((event.type === 'keyup' && event.key === TAB_KEY) ||
            /input|select|option|textarea|form/i.test(event.target.tagName))
        ) {
          continue;
        }

        if (event.type === 'click') {
          relatedTarget.clickEvent = event;
        }
      }

      context._completeHide(relatedTarget);
    }
  }

  static getParentFromElement(element) {
    return getElementFromSelector(element) || element.parentNode;
  }

  static dataApiKeydownHandler(event) {
    // If not input/textarea:
    //  - And not a key in REGEXP_KEYDOWN => not a dropdown command
    // If input/textarea:
    //  - If space key => not a dropdown command
    //  - If key is other than escape
    //    - If key is not up or down => not a dropdown command
    //    - If trigger inside the menu => not a dropdown command
    if (
      /input|textarea/i.test(event.target.tagName)
        ? event.key === SPACE_KEY ||
          (event.key !== ESCAPE_KEY &&
            ((event.key !== ARROW_DOWN_KEY && event.key !== ARROW_UP_KEY) ||
              event.target.closest(SELECTOR_MENU)))
        : !REGEXP_KEYDOWN.test(event.key)
    ) {
      return;
    }

    const isActive = this.classList.contains(CLASS_NAME_SHOW);

    if (!isActive && event.key === ESCAPE_KEY) {
      return;
    }

    event.preventDefault();
    event.stopPropagation();

    if (isDisabled(this)) {
      return;
    }

    const getToggleButton = this.matches(SELECTOR_DATA_TOGGLE)
      ? this
      : SelectorEngine.prev(this, SELECTOR_DATA_TOGGLE)[0];
    const instance = Dropdown.getOrCreateInstance(getToggleButton);

    if (event.key === ESCAPE_KEY) {
      instance.hide();
      return;
    }

    if (event.key === ARROW_UP_KEY || event.key === ARROW_DOWN_KEY) {
      if (!isActive) {
        instance.show();
      }

      instance._selectMenuItem(event);
      return;
    }

    if (!isActive || event.key === SPACE_KEY) {
      Dropdown.clearMenus();
    }
  }
}

/**
 * ------------------------------------------------------------------------
 * Data Api implementation
 * ------------------------------------------------------------------------
 */

EventHandler.on(
  document,
  EVENT_KEYDOWN_DATA_API,
  SELECTOR_DATA_TOGGLE,
  Dropdown.dataApiKeydownHandler
);
EventHandler.on(document, EVENT_KEYDOWN_DATA_API, SELECTOR_MENU, Dropdown.dataApiKeydownHandler);
EventHandler.on(document, EVENT_CLICK_DATA_API, Dropdown.clearMenus);
EventHandler.on(document, EVENT_KEYUP_DATA_API, Dropdown.clearMenus);
EventHandler.on(document, EVENT_CLICK_DATA_API, SELECTOR_DATA_TOGGLE, function (event) {
  event.preventDefault();
  Dropdown.getOrCreateInstance(this).toggle();
});

/**
 * ------------------------------------------------------------------------
 * jQuery
 * ------------------------------------------------------------------------
 * add .Dropdown to jQuery only if jQuery is present
 */

defineJQueryPlugin(Dropdown);

export default Dropdown;