import $ from 'jquery';
import { escape } from 'lodash';
import axios from './lib/utils/axios_utils';
import Api from './api';
import { normalizeHeaders } from './lib/utils/common_utils';
import { __ } from '~/locale';

const groupsSelect = () => {
  // Needs to be accessible in rspec
  window.GROUP_SELECT_PER_PAGE = 20;
  $('.ajax-groups-select').each(function setAjaxGroupsSelect2() {
    const $select = $(this);
    const allAvailable = $select.data('allAvailable');
    const skipGroups = $select.data('skipGroups') || [];
    const parentGroupID = $select.data('parentId');
    const groupsPath = parentGroupID
      ? Api.subgroupsPath.replace(':id', parentGroupID)
      : Api.groupsPath;

    $select.select2({
      placeholder: __('Search for a group'),
      allowClear: $select.hasClass('allowClear'),
      multiple: $select.hasClass('multiselect'),
      minimumInputLength: 0,
      ajax: {
        url: Api.buildUrl(groupsPath),
        dataType: 'json',
        quietMillis: 250,
        transport(params) {
          axios[params.type.toLowerCase()](params.url, {
            params: params.data,
          })
            .then(res => {
              const results = res.data || [];
              const headers = normalizeHeaders(res.headers);
              const currentPage = parseInt(headers['X-PAGE'], 10) || 0;
              const totalPages = parseInt(headers['X-TOTAL-PAGES'], 10) || 0;
              const more = currentPage < totalPages;

              params.success({
                results,
                pagination: {
                  more,
                },
              });
            })
            .catch(params.error);
        },
        data(search, page) {
          return {
            search,
            page,
            per_page: window.GROUP_SELECT_PER_PAGE,
            all_available: allAvailable,
          };
        },
        results(data, page) {
          if (data.length) return { results: [] };

          const groups = data.length ? data : data.results || [];
          const more = data.pagination ? data.pagination.more : false;
          const results = groups.filter(group => skipGroups.indexOf(group.id) === -1);

          return {
            results,
            page,
            more,
          };
        },
      },
      // eslint-disable-next-line consistent-return
      initSelection(element, callback) {
        const id = $(element).val();
        if (id !== '') {
          return Api.group(id, callback);
        }
      },
      formatResult(object) {
        return `<div class='group-result'> <div class='group-name'>${escape(
          object.full_name,
        )}</div> <div class='group-path'>${object.full_path}</div> </div>`;
      },
      formatSelection(object) {
        return escape(object.full_name);
      },
      dropdownCssClass: 'ajax-groups-dropdown select2-infinite',
      // we do not want to escape markup since we are displaying html in results
      escapeMarkup(m) {
        return m;
      },
    });

    $select.on('select2-loaded', () => {
      const dropdown = document.querySelector('.select2-infinite .select2-results');
      dropdown.style.height = `${Math.floor(dropdown.scrollHeight)}px`;
    });
  });
};

export default () => {
  if ($('.ajax-groups-select').length) {
    import(/* webpackChunkName: 'select2' */ 'select2/select2')
      .then(groupsSelect)
      .catch(() => {});
  }
};