/**
 * @file
 * Some basic behaviors and utility functions for Views.
 */

(function ($, Drupal, drupalSettings) {
  /**
   * @namespace
   */
  Drupal.Views = {};

  /**
   * Helper function to parse a querystring.
   *
   * @param {string} query
   *   The querystring to parse.
   *
   * @return {object}
   *   A map of query parameters.
   */
  Drupal.Views.parseQueryString = function (query) {
    const args = {};
    const pos = query.indexOf('?');
    if (pos !== -1) {
      query = query.substring(pos + 1);
    }
    let pair;
    const pairs = query.split('&');
    for (let i = 0; i < pairs.length; i++) {
      pair = pairs[i].split('=');
      // Ignore the 'q' path argument, if present.
      if (pair[0] !== 'q' && pair[1]) {
        args[decodeURIComponent(pair[0].replace(/\+/g, ' '))] = decodeURIComponent(pair[1].replace(/\+/g, ' '));
      }
    }
    return args;
  };

  /**
   * Helper function to return a view's arguments based on a path.
   *
   * @param {string} href
   *   The href to check.
   * @param {string} viewPath
   *   The views path to check.
   *
   * @return {object}
   *   An object containing `view_args` and `view_path`.
   */
  Drupal.Views.parseViewArgs = function (href, viewPath) {
    const returnObj = {};
    const path = Drupal.Views.getPath(href);
    // Get viewPath url without baseUrl portion.
    const viewHref = Drupal.url(viewPath).substring(drupalSettings.path.baseUrl.length);
    // Ensure we have a correct path.
    if (viewHref && path.substring(0, viewHref.length + 1) === `${viewHref}/`) {
      returnObj.view_args = decodeURIComponent(path.substring(viewHref.length + 1, path.length));
      returnObj.view_path = path;
    }
    return returnObj;
  };

  /**
   * Strip off the protocol plus domain from an href.
   *
   * @param {string} href
   *   The href to strip.
   *
   * @return {string}
   *   The href without the protocol and domain.
   */
  Drupal.Views.pathPortion = function (href) {
    // Remove e.g. http://example.com if present.
    const protocol = window.location.protocol;
    if (href.substring(0, protocol.length) === protocol) {
      // 2 is the length of the '//' that normally follows the protocol.
      href = href.substring(href.indexOf('/', protocol.length + 2));
    }
    return href;
  };

  /**
   * Return the Drupal path portion of an href.
   *
   * @param {string} href
   *   The href to check.
   *
   * @return {string}
   *   An internal path.
   */
  Drupal.Views.getPath = function (href) {
    href = Drupal.Views.pathPortion(href);
    href = href.substring(drupalSettings.path.baseUrl.length, href.length);
    // 3 is the length of the '?q=' added to the url without clean urls.
    if (href.substring(0, 3) === '?q=') {
      href = href.substring(3, href.length);
    }
    const chars = ['#', '?', '&'];
    for (let i = 0; i < chars.length; i++) {
      if (href.indexOf(chars[i]) > -1) {
        href = href.substr(0, href.indexOf(chars[i]));
      }
    }
    return href;
  };
}(jQuery, Drupal, drupalSettings));