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import $ from 'jquery';import {generateAriaId} from './base.js'; const ariaPatchKey = '_giteaAriaPatchDropdown';const fomanticDropdownFn = $.fn.dropdown; // use our own `$().dropdown` function to patch Fomantic's dropdown moduleexport function initAriaDropdownPatch() {  if ($.fn.dropdown === ariaDropdownFn) throw new Error('initAriaDropdownPatch could only be called once');  $.fn.dropdown = ariaDropdownFn;  ariaDropdownFn.settings = fomanticDropdownFn.settings;} // the patched `$.fn.dropdown` function, it passes the arguments to Fomantic's `$.fn.dropdown` function, and:// * it does the one-time attaching on the first call// * it delegates the `onLabelCreate` to the patched `onLabelCreate` to add necessary aria attributesfunction ariaDropdownFn(...args) {  const ret = fomanticDropdownFn.apply(this, args);   // if the `$().dropdown()` call is without arguments, or it has non-string (object) argument,  // it means that this call will reset the dropdown internal settings, then we need to re-delegate the callbacks.  const needDelegate = (!args.length || typeof args[0] !== 'string');  for (const el of this) {    if (!el[ariaPatchKey]) {      attachInit(el);    }    if (needDelegate) {      delegateOne($(el));    }  }  return ret;} // make the item has role=option/menuitem, add an id if there wasn't one yet, make items as non-focusable// the elements inside the dropdown menu item should not be focusable, the focus should always be on the dropdown primary element.function updateMenuItem(dropdown, item) {  if (!item.id) item.id = generateAriaId();  item.setAttribute('role', dropdown[ariaPatchKey].listItemRole);  item.setAttribute('tabindex', '-1');  for (const el of item.querySelectorAll('a, input, button')) el.setAttribute('tabindex', '-1');}/** * make the label item and its "delete icon" have correct aria attributes * @param {HTMLElement} label */function updateSelectionLabel(label) {  // the "label" is like this: "<a|div class="ui label" data-value="1">the-label-name <i|svg class="delete icon"/></a>"  if (!label.id) {    label.id = generateAriaId();  }  label.tabIndex = -1;   const deleteIcon = label.querySelector('.delete.icon');  if (deleteIcon) {    deleteIcon.setAttribute('aria-hidden', 'false');    deleteIcon.setAttribute('aria-label', window.config.i18n.remove_label_str.replace('%s', label.getAttribute('data-value')));    deleteIcon.setAttribute('role', 'button');  }} // delegate the dropdown's template functions and callback functions to add aria attributes.function delegateOne($dropdown) {  const dropdownCall = fomanticDropdownFn.bind($dropdown);   // If there is a "search input" in the "menu", Fomantic will only "focus the input" but not "toggle the menu" when the "dropdown icon" is clicked.  // Actually, Fomantic UI doesn't support such layout/usage. It needs to patch the "focusSearch" / "blurSearch" functions to make sure it toggles the menu.  const oldFocusSearch = dropdownCall('internal', 'focusSearch');  const oldBlurSearch = dropdownCall('internal', 'blurSearch');  // * If the "dropdown icon" is clicked, Fomantic calls "focusSearch", so show the menu  dropdownCall('internal', 'focusSearch', function () { dropdownCall('show'); oldFocusSearch.call(this) });  // * If the "dropdown icon" is clicked again when the menu is visible, Fomantic calls "blurSearch", so hide the menu  dropdownCall('internal', 'blurSearch', function () { oldBlurSearch.call(this); dropdownCall('hide') });   // the "template" functions are used for dynamic creation (eg: AJAX)  const dropdownTemplates = {...dropdownCall('setting', 'templates'), t: performance.now()};  const dropdownTemplatesMenuOld = dropdownTemplates.menu;  dropdownTemplates.menu = function(response, fields, preserveHTML, className) {    // when the dropdown menu items are loaded from AJAX requests, the items are created dynamically    const menuItems = dropdownTemplatesMenuOld(response, fields, preserveHTML, className);    const div = document.createElement('div');    div.innerHTML = menuItems;    const $wrapper = $(div);    const $items = $wrapper.find('> .item');    $items.each((_, item) => updateMenuItem($dropdown[0], item));    $dropdown[0][ariaPatchKey].deferredRefreshAriaActiveItem();    return $wrapper.html();  };  dropdownCall('setting', 'templates', dropdownTemplates);   // the `onLabelCreate` is used to add necessary aria attributes for dynamically created selection labels  const dropdownOnLabelCreateOld = dropdownCall('setting', 'onLabelCreate');  dropdownCall('setting', 'onLabelCreate', function(value, text) {    const $label = dropdownOnLabelCreateOld.call(this, value, text);    updateSelectionLabel($label[0]);    return $label;  });} // for static dropdown elements (generated by server-side template), prepare them with necessary aria attributesfunction attachStaticElements(dropdown, focusable, menu) {  // prepare static dropdown menu list popup  if (!menu.id) {    menu.id = generateAriaId();  }   $(menu).find('> .item').each((_, item) => updateMenuItem(dropdown, item));   // this role could only be changed after its content is ready, otherwise some browsers+readers (like Chrome+AppleVoice) crash  menu.setAttribute('role', dropdown[ariaPatchKey].listPopupRole);   // prepare selection label items  for (const label of dropdown.querySelectorAll('.ui.label')) {    updateSelectionLabel(label);  }   // make the primary element (focusable) aria-friendly  focusable.setAttribute('role', focusable.getAttribute('role') ?? dropdown[ariaPatchKey].focusableRole);  focusable.setAttribute('aria-haspopup', dropdown[ariaPatchKey].listPopupRole);  focusable.setAttribute('aria-controls', menu.id);  focusable.setAttribute('aria-expanded', 'false');   // use tooltip's content as aria-label if there is no aria-label  const tooltipContent = dropdown.getAttribute('data-tooltip-content');  if (tooltipContent && !dropdown.getAttribute('aria-label')) {    dropdown.setAttribute('aria-label', tooltipContent);  }} function attachInit(dropdown) {  dropdown[ariaPatchKey] = {};  if (dropdown.classList.contains('custom')) return;   // Dropdown has 2 different focusing behaviors  // * with search input: the input is focused, and it works with aria-activedescendant pointing another sibling element.  // * without search input (but the readonly text), the dropdown itself is focused. then the aria-activedescendant points to the element inside dropdown  // Some desktop screen readers may change the focus, but dropdown requires that the focus must be on its primary element, then they don't work well.   // Expected user interactions for dropdown with aria support:  // * user can use Tab to focus in the dropdown, then the dropdown menu (list) will be shown  // * user presses Tab on the focused dropdown to move focus to next sibling focusable element (but not the menu item)  // * user can use arrow key Up/Down to navigate between menu items  // * when user presses Enter:  //    - if the menu item is clickable (eg: <a>), then trigger the click event  //    - otherwise, the dropdown control (low-level code) handles the Enter event, hides the dropdown menu   // TODO: multiple selection is only partially supported. Check and test them one by one in the future.   const textSearch = dropdown.querySelector('input.search');  const focusable = textSearch || dropdown; // the primary element for focus, see comment above  if (!focusable) return;   // as a combobox, the input should not have autocomplete by default  if (textSearch && !textSearch.getAttribute('autocomplete')) {    textSearch.setAttribute('autocomplete', 'off');  }   let menu = $(dropdown).find('> .menu')[0];  if (!menu) {    // some "multiple selection" dropdowns don't have a static menu element in HTML, we need to pre-create it to make it have correct aria attributes    menu = document.createElement('div');    menu.classList.add('menu');    dropdown.append(menu);  }   // There are 2 possible solutions about the role: combobox or menu.  // The idea is that if there is an input, then it's a combobox, otherwise it's a menu.  // Since #19861 we have prepared the "combobox" solution, but didn't get enough time to put it into practice and test before.  const isComboBox = dropdown.querySelectorAll('input').length > 0;   dropdown[ariaPatchKey].focusableRole = isComboBox ? 'combobox' : 'menu';  dropdown[ariaPatchKey].listPopupRole = isComboBox ? 'listbox' : '';  dropdown[ariaPatchKey].listItemRole = isComboBox ? 'option' : 'menuitem';   attachDomEvents(dropdown, focusable, menu);  attachStaticElements(dropdown, focusable, menu);} function attachDomEvents(dropdown, focusable, menu) {  // when showing, it has class: ".animating.in"  // when hiding, it has class: ".visible.animating.out"  const isMenuVisible = () => (menu.classList.contains('visible') && !menu.classList.contains('out')) || menu.classList.contains('in');   // update aria attributes according to current active/selected item  const refreshAriaActiveItem = () => {    const menuVisible = isMenuVisible();    focusable.setAttribute('aria-expanded', menuVisible ? 'true' : 'false');     // if there is an active item, use it (the user is navigating between items)    // otherwise use the "selected" for combobox (for the last selected item)    const active = $(menu).find('> .item.active, > .item.selected')[0];    if (!active) return;    // if the popup is visible and has an active/selected item, use its id as aria-activedescendant    if (menuVisible) {      focusable.setAttribute('aria-activedescendant', active.id);    } else if (dropdown[ariaPatchKey].listPopupRole === 'menu') {      // for menu, when the popup is hidden, no need to keep the aria-activedescendant, and clear the active/selected item      focusable.removeAttribute('aria-activedescendant');      active.classList.remove('active', 'selected');    }  };   dropdown.addEventListener('keydown', (e) => {    // here it must use keydown event before dropdown's keyup handler, otherwise there is no Enter event in our keyup handler    if (e.key === 'Enter') {      const dropdownCall = fomanticDropdownFn.bind($(dropdown));      let $item = dropdownCall('get item', dropdownCall('get value'));      if (!$item) $item = $(menu).find('> .item.selected'); // when dropdown filters items by input, there is no "value", so query the "selected" item      // if the selected item is clickable, then trigger the click event.      // we can not click any item without check, because Fomantic code might also handle the Enter event. that would result in double click.      if ($item?.[0]?.matches('a, .js-aria-clickable')) $item[0].click();    }  });   // use setTimeout to run the refreshAria in next tick (to make sure the Fomantic UI code has finished its work)  // do not return any value, jQuery has return-value related behaviors.  // when the popup is hiding, it's better to have a small "delay", because there is a Fomantic UI animation  // without the delay for hiding, the UI will be somewhat laggy and sometimes may get stuck in the animation.  const deferredRefreshAriaActiveItem = (delay = 0) => { setTimeout(refreshAriaActiveItem, delay) };  dropdown[ariaPatchKey].deferredRefreshAriaActiveItem = deferredRefreshAriaActiveItem;  dropdown.addEventListener('keyup', (e) => { if (e.key.startsWith('Arrow')) deferredRefreshAriaActiveItem(); });   // if the dropdown has been opened by focus, do not trigger the next click event again.  // otherwise the dropdown will be closed immediately, especially on Android with TalkBack  // * desktop event sequence: mousedown -> focus -> mouseup -> click  // * mobile event sequence: focus -> mousedown -> mouseup -> click  // Fomantic may stop propagation of blur event, use capture to make sure we can still get the event  let ignoreClickPreEvents = 0, ignoreClickPreVisible = 0;  dropdown.addEventListener('mousedown', () => {    ignoreClickPreVisible += isMenuVisible() ? 1 : 0;    ignoreClickPreEvents++;  }, true);  dropdown.addEventListener('focus', () => {    ignoreClickPreVisible += isMenuVisible() ? 1 : 0;    ignoreClickPreEvents++;    deferredRefreshAriaActiveItem();  }, true);  dropdown.addEventListener('blur', () => {    ignoreClickPreVisible = ignoreClickPreEvents = 0;    deferredRefreshAriaActiveItem(100);  }, true);  dropdown.addEventListener('mouseup', () => {    setTimeout(() => {      ignoreClickPreVisible = ignoreClickPreEvents = 0;      deferredRefreshAriaActiveItem(100);    }, 0);  }, true);  dropdown.addEventListener('click', (e) => {    if (isMenuVisible() &&      ignoreClickPreVisible !== 2 && // dropdown is switch from invisible to visible      ignoreClickPreEvents === 2 // the click event is related to mousedown+focus    ) {      e.stopPropagation(); // if the dropdown menu has been opened by focus, do not trigger the next click event again    }    ignoreClickPreEvents = ignoreClickPreVisible = 0;  }, true);}