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   1  /**
   2   * @copyright  (C) 2020 Open Source Matters, Inc. <https://www.joomla.org>
   3   * @license    GNU General Public License version 2 or later; see LICENSE.txt
   4   */
   5  
   6  /**
   7   * Add a keyboard event listener to the Select a Module Type search element.
   8   *
   9   * IMPORTANT! This script is meant to be loaded deferred. This means that a. it's non-blocking
  10   * (the browser can load it whenever) and b. it doesn't need an on DOMContentLoaded event handler
  11   * because the browser is guaranteed to execute it only after the DOM content has loaded, the
  12   * whole point of it being deferred.
  13   *
  14   * The search box has a keyboard handler that fires every time you press a keyboard button or send
  15   * a keypress with a touch / virtual keyboard. We then iterate all module type cards and check if
  16   * the plain text (HTML stripped out) representation of the module title or description partially
  17   * matches the text you entered in the search box. If it doesn't we add a Bootstrap class to hide
  18   * the module.
  19   *
  20   * This way we limit the displayed modules only to those searched.
  21   *
  22   * This feature follows progressive enhancement. The search box is hidden by default and only
  23   * displayed when this JavaScript here executes. Furthermore, session storage is only used if it
  24   * is available in the browser. That's a bit of a pain but makes sure things won't break in older
  25   * browsers.
  26   *
  27   * Furthermore and to facilitate the user experience we auto-focus the search element which has a
  28   * suitable title so that non-sighted users are not startled. This way we address both UX concerns
  29   * and accessibility.
  30   *
  31   * Finally, the search string is saved into session storage on the assumption that the user is
  32   * probably going to be creating multiple instances of the same module, one after another, as is
  33   * typical when building a new Joomla! site.
  34   */
  35  // Make sure the element exists i.e. a template override has not removed it.
  36  const elSearch = document.getElementById('comModulesSelectSearch');
  37  const elSearchContainer = document.getElementById('comModulesSelectSearchContainer');
  38  const elSearchHeader = document.getElementById('comModulesSelectTypeHeader');
  39  const elSearchResults = document.getElementById('comModulesSelectResultsContainer');
  40  const alertElement = document.querySelector('.modules-alert');
  41  const elCards = [].slice.call(document.querySelectorAll('.comModulesSelectCard'));
  42  
  43  if (elSearch && elSearchContainer) {
  44    // Add the keyboard event listener which performs the live search in the cards
  45    elSearch.addEventListener('keyup', event => {
  46      /** @type {KeyboardEvent} event */
  47      const partialSearch = event.target.value;
  48      let hasSearchResults = false; // Save the search string into session storage
  49  
  50      if (typeof sessionStorage !== 'undefined') {
  51        sessionStorage.setItem('Joomla.com_modules.new.search', partialSearch);
  52      } // Iterate all the module cards
  53  
  54  
  55      elCards.forEach(card => {
  56        // First remove the class which hide the module cards
  57        card.classList.remove('d-none'); // An empty search string means that we should show everything
  58  
  59        if (!partialSearch) {
  60          return;
  61        }
  62  
  63        const cardHeader = card.querySelector('.new-module-title');
  64        const cardBody = card.querySelector('.card-body');
  65        const title = cardHeader ? cardHeader.textContent : '';
  66        const description = cardBody ? cardBody.textContent : ''; // If the module title and description don’t match add a class to hide it.
  67  
  68        if (title && !title.toLowerCase().includes(partialSearch.toLowerCase()) && description && !description.toLowerCase().includes(partialSearch.toLowerCase())) {
  69          card.classList.add('d-none');
  70        } else {
  71          hasSearchResults = true;
  72        }
  73      });
  74  
  75      if (hasSearchResults || !partialSearch) {
  76        alertElement.classList.add('d-none');
  77        elSearchHeader.classList.remove('d-none');
  78        elSearchResults.classList.remove('d-none');
  79      } else {
  80        alertElement.classList.remove('d-none');
  81        elSearchHeader.classList.add('d-none');
  82        elSearchResults.classList.add('d-none');
  83      }
  84    }); // For reasons of progressive enhancement the search box is hidden by default.
  85  
  86    elSearchContainer.classList.remove('d-none'); // Focus the just show element
  87  
  88    elSearch.focus();
  89  
  90    try {
  91      if (typeof sessionStorage !== 'undefined') {
  92        // Load the search string from session storage
  93        elSearch.value = sessionStorage.getItem('Joomla.com_modules.new.search') || ''; // Trigger the keyboard handler event manually to initiate the search
  94  
  95        elSearch.dispatchEvent(new KeyboardEvent('keyup'));
  96      }
  97    } catch (e) {// This is probably Internet Explorer which doesn't support the KeyboardEvent constructor :(
  98    }
  99  }