mdb-ui-kit/src/js/bootstrap/mdb-prefix/tab.js

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v5.2.3): tab.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
 * --------------------------------------------------------------------------
 */

import {
  defineJQueryPlugin,
  getElementFromSelector,
  getNextActiveElement,
  isDisabled,
} from './util/index';
import EventHandler from './dom/event-handler';
import SelectorEngine from './dom/selector-engine';
import BaseComponent from './base-component';

/**
 * Constants
 */

const NAME = 'tab';
const DATA_KEY = 'bs.tab';
const EVENT_KEY = `.${DATA_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${EVENT_KEY}`;
const EVENT_KEYDOWN = `keydown${EVENT_KEY}`;
const EVENT_LOAD_DATA_API = `load${EVENT_KEY}`;

const ARROW_LEFT_KEY = 'ArrowLeft';
const ARROW_RIGHT_KEY = 'ArrowRight';
const ARROW_UP_KEY = 'ArrowUp';
const ARROW_DOWN_KEY = 'ArrowDown';

const CLASS_NAME_ACTIVE = 'active';
const CLASS_NAME_FADE = 'fade';
const CLASS_NAME_SHOW = 'show';
const CLASS_DROPDOWN = 'dropdown';

const SELECTOR_DROPDOWN_TOGGLE = '.dropdown-toggle';
const SELECTOR_DROPDOWN_MENU = '.dropdown-menu';
const NOT_SELECTOR_DROPDOWN_TOGGLE = ':not(.dropdown-toggle)';

const SELECTOR_TAB_PANEL = '.list-group, .nav, [role="tablist"]';
const SELECTOR_OUTER = '.nav-item, .list-group-item';
const SELECTOR_INNER = `.nav-link${NOT_SELECTOR_DROPDOWN_TOGGLE}, .list-group-item${NOT_SELECTOR_DROPDOWN_TOGGLE}, [role="tab"]${NOT_SELECTOR_DROPDOWN_TOGGLE}`;
const SELECTOR_DATA_TOGGLE =
  '[data-mdb-toggle="tab"], [data-mdb-toggle="pill"], [data-mdb-toggle="list"]'; // todo:v6: could be only `tab`
const SELECTOR_INNER_ELEM = `${SELECTOR_INNER}, ${SELECTOR_DATA_TOGGLE}`;

const SELECTOR_DATA_TOGGLE_ACTIVE = `.${CLASS_NAME_ACTIVE}[data-mdb-toggle="tab"], .${CLASS_NAME_ACTIVE}[data-mdb-toggle="pill"], .${CLASS_NAME_ACTIVE}[data-mdb-toggle="list"]`;

/**
 * Class definition
 */

class Tab extends BaseComponent {
  constructor(element) {
    super(element);
    this._parent = this._element.closest(SELECTOR_TAB_PANEL);

    if (!this._parent) {
      return;
      // todo: should Throw exception on v6
      // throw new TypeError(`${element.outerHTML} has not a valid parent ${SELECTOR_INNER_ELEM}`)
    }

    // Set up initial aria attributes
    this._setInitialAttributes(this._parent, this._getChildren());

    EventHandler.on(this._element, EVENT_KEYDOWN, (event) => this._keydown(event));
  }

  // Getters
  static get NAME() {
    return NAME;
  }

  // Public
  show() {
    // Shows this elem and deactivate the active sibling if exists
    const innerElem = this._element;
    if (this._elemIsActive(innerElem)) {
      return;
    }

    // Search for active tab on same parent to deactivate it
    const active = this._getActiveElem();

    const hideEvent = active
      ? EventHandler.trigger(active, EVENT_HIDE, { relatedTarget: innerElem })
      : null;

    const showEvent = EventHandler.trigger(innerElem, EVENT_SHOW, { relatedTarget: active });

    if (showEvent.defaultPrevented || (hideEvent && hideEvent.defaultPrevented)) {
      return;
    }

    this._deactivate(active, innerElem);
    this._activate(innerElem, active);
  }

  // Private
  _activate(element, relatedElem) {
    if (!element) {
      return;
    }

    element.classList.add(CLASS_NAME_ACTIVE);

    this._activate(getElementFromSelector(element)); // Search and activate/show the proper section

    const complete = () => {
      if (element.getAttribute('role') !== 'tab') {
        element.classList.add(CLASS_NAME_SHOW);
        return;
      }

      element.removeAttribute('tabindex');
      element.setAttribute('aria-selected', true);
      this._toggleDropDown(element, true);
      EventHandler.trigger(element, EVENT_SHOWN, {
        relatedTarget: relatedElem,
      });
    };

    this._queueCallback(complete, element, element.classList.contains(CLASS_NAME_FADE));
  }

  _deactivate(element, relatedElem) {
    if (!element) {
      return;
    }

    element.classList.remove(CLASS_NAME_ACTIVE);
    element.blur();

    this._deactivate(getElementFromSelector(element)); // Search and deactivate the shown section too

    const complete = () => {
      if (element.getAttribute('role') !== 'tab') {
        element.classList.remove(CLASS_NAME_SHOW);
        return;
      }

      element.setAttribute('aria-selected', false);
      element.setAttribute('tabindex', '-1');
      this._toggleDropDown(element, false);
      EventHandler.trigger(element, EVENT_HIDDEN, { relatedTarget: relatedElem });
    };

    this._queueCallback(complete, element, element.classList.contains(CLASS_NAME_FADE));
  }

  _keydown(event) {
    if (![ARROW_LEFT_KEY, ARROW_RIGHT_KEY, ARROW_UP_KEY, ARROW_DOWN_KEY].includes(event.key)) {
      return;
    }

    event.stopPropagation(); // stopPropagation/preventDefault both added to support up/down keys without scrolling the page
    event.preventDefault();
    const isNext = [ARROW_RIGHT_KEY, ARROW_DOWN_KEY].includes(event.key);
    const nextActiveElement = getNextActiveElement(
      this._getChildren().filter((element) => !isDisabled(element)),
      event.target,
      isNext,
      true
    );

    if (nextActiveElement) {
      nextActiveElement.focus({ preventScroll: true });
      Tab.getOrCreateInstance(nextActiveElement).show();
    }
  }

  _getChildren() {
    // collection of inner elements
    return SelectorEngine.find(SELECTOR_INNER_ELEM, this._parent);
  }

  _getActiveElem() {
    return this._getChildren().find((child) => this._elemIsActive(child)) || null;
  }

  _setInitialAttributes(parent, children) {
    this._setAttributeIfNotExists(parent, 'role', 'tablist');

    for (const child of children) {
      this._setInitialAttributesOnChild(child);
    }
  }

  _setInitialAttributesOnChild(child) {
    child = this._getInnerElement(child);
    const isActive = this._elemIsActive(child);
    const outerElem = this._getOuterElement(child);
    child.setAttribute('aria-selected', isActive);

    if (outerElem !== child) {
      this._setAttributeIfNotExists(outerElem, 'role', 'presentation');
    }

    if (!isActive) {
      child.setAttribute('tabindex', '-1');
    }

    this._setAttributeIfNotExists(child, 'role', 'tab');

    // set attributes to the related panel too
    this._setInitialAttributesOnTargetPanel(child);
  }

  _setInitialAttributesOnTargetPanel(child) {
    const target = getElementFromSelector(child);

    if (!target) {
      return;
    }

    this._setAttributeIfNotExists(target, 'role', 'tabpanel');

    if (child.id) {
      this._setAttributeIfNotExists(target, 'aria-labelledby', `#${child.id}`);
    }
  }

  _toggleDropDown(element, open) {
    const outerElem = this._getOuterElement(element);
    if (!outerElem.classList.contains(CLASS_DROPDOWN)) {
      return;
    }

    const toggle = (selector, className) => {
      const element = SelectorEngine.findOne(selector, outerElem);
      if (element) {
        element.classList.toggle(className, open);
      }
    };

    toggle(SELECTOR_DROPDOWN_TOGGLE, CLASS_NAME_ACTIVE);
    toggle(SELECTOR_DROPDOWN_MENU, CLASS_NAME_SHOW);
    outerElem.setAttribute('aria-expanded', open);
  }

  _setAttributeIfNotExists(element, attribute, value) {
    if (!element.hasAttribute(attribute)) {
      element.setAttribute(attribute, value);
    }
  }

  _elemIsActive(elem) {
    return elem.classList.contains(CLASS_NAME_ACTIVE);
  }

  // Try to get the inner element (usually the .nav-link)
  _getInnerElement(elem) {
    return elem.matches(SELECTOR_INNER_ELEM)
      ? elem
      : SelectorEngine.findOne(SELECTOR_INNER_ELEM, elem);
  }

  // Try to get the outer element (usually the .nav-item)
  _getOuterElement(elem) {
    return elem.closest(SELECTOR_OUTER) || elem;
  }

  // Static
  static jQueryInterface(config) {
    return this.each(function () {
      const data = Tab.getOrCreateInstance(this);

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

      if (data[config] === undefined || config.startsWith('_') || config === 'constructor') {
        throw new TypeError(`No method named "${config}"`);
      }

      data[config]();
    });
  }
}

/**
 * Data API implementation
 */

EventHandler.on(document, EVENT_CLICK_DATA_API, SELECTOR_DATA_TOGGLE, function (event) {
  if (['A', 'AREA'].includes(this.tagName)) {
    event.preventDefault();
  }

  if (isDisabled(this)) {
    return;
  }

  Tab.getOrCreateInstance(this).show();
});

/**
 * Initialize on focus
 */
EventHandler.on(window, EVENT_LOAD_DATA_API, () => {
  for (const element of SelectorEngine.find(SELECTOR_DATA_TOGGLE_ACTIVE)) {
    Tab.getOrCreateInstance(element);
  }
});
/**
 * jQuery
 */

defineJQueryPlugin(Tab);

export default Tab;