(function (root, factory) {
  // 帮助中心模块同时支持浏览器页面和 Node 单元测试。
  if (typeof module === 'object' && module.exports) {
    module.exports = factory(root);
    return;
  }

  root.HelpPages = factory(root);
  if (root.document) {
    root.document.addEventListener('DOMContentLoaded', function () {
      root.HelpPages.init();
    });
  }
})(typeof globalThis !== 'undefined' ? globalThis : window, function (root) {
  'use strict';

  var documentRef = root.document;

  function normalizeList(data) {
    // 通用列表响应可能是数组，也可能包在 rows、records、list 或 data 中。
    if (Array.isArray(data)) return data;
    if (!data || typeof data !== 'object') return [];
    if (Array.isArray(data.rows)) return data.rows;
    if (Array.isArray(data.records)) return data.records;
    if (Array.isArray(data.list)) return data.list;
    if (Array.isArray(data.data)) return data.data;
    return [];
  }

  function pick(item, keys, fallback) {
    var source = item || {};
    var index;
    var value;

    for (index = 0; index < keys.length; index += 1) {
      value = source[keys[index]];
      if (value !== undefined && value !== null && value !== '') return value;
    }

    return fallback || '';
  }

  function escapeHtml(value) {
    // 帮助文章来自接口，进入 innerHTML 前先转义。
    return String(value === undefined || value === null ? '' : value)
      .replace(/&/g, '&amp;')
      .replace(/</g, '&lt;')
      .replace(/>/g, '&gt;')
      .replace(/"/g, '&quot;')
      .replace(/'/g, '&#39;');
  }

  function getApi() {
    return root.GenealogyApi && root.GenealogyApi.defaultClient;
  }

  function query(selector, rootNode) {
    return (rootNode || documentRef).querySelector(selector);
  }

  function showMessage(message) {
    if (root.layui && root.layui.layer) {
      root.layui.layer.msg(message);
      return;
    }

    root.alert(message);
  }

  function buildHelpItem(item, index) {
    // 列表接口字段未在文档中细化，这里兼容常见标题和摘要字段。
    var id = pick(item, ['helpId', 'id', 'articleId'], '');
    var title = pick(item, ['title', 'articleTitle', 'name'], '帮助文章');
    var content = pick(item, ['summary', 'description', 'content', 'articleContent'], '暂无详细说明');
    var hasFullContent = Boolean(pick(item, ['content', 'articleContent'], ''));
    var open = index === 0 ? ' open' : '';

    return '<details' + open + ' class="tilt-card" data-help-id="' + escapeHtml(id) + '" data-help-loaded="' + (hasFullContent ? 'true' : 'false') + '">' +
      '<summary>' + escapeHtml(title) + '</summary>' +
      '<p>' + escapeHtml(content) + '</p>' +
      '</details>';
  }

  function renderHelpArticles(items) {
    var container = query('[data-help-list]');

    if (!container) return;
    if (!items.length) {
      container.innerHTML = '<div class="api-empty">暂无帮助文章</div>';
      return;
    }

    container.innerHTML = items.map(buildHelpItem).join('');
  }

  async function loadHelpArticles() {
    var api = getApi();
    var container = query('[data-help-list]');

    if (!api || !container) return;

    container.classList.add('is-loading');
    try {
      renderHelpArticles(normalizeList(await api.helpArticles()));
    } catch (error) {
      showMessage(error.message || '帮助文章加载失败');
    } finally {
      container.classList.remove('is-loading');
    }
  }

  async function loadHelpDetail(details) {
    var api = getApi();
    var helpId = details && details.getAttribute('data-help-id');
    var paragraph = details && query('p', details);
    var content;

    if (!api || !details || !helpId || details.getAttribute('data-help-loaded') === 'true') return;

    details.classList.add('is-loading');
    try {
      content = await api.helpArticleDetail(helpId);
      paragraph.textContent = pick(content, ['content', 'articleContent', 'summary', 'description'], paragraph.textContent);
      details.setAttribute('data-help-loaded', 'true');
    } catch (error) {
      showMessage(error.message || '帮助详情加载失败');
    } finally {
      details.classList.remove('is-loading');
    }
  }

  function bindDetailLoad() {
    var container = query('[data-help-list]');

    if (!container) return;
    container.addEventListener('toggle', function (event) {
      if (event.target && event.target.matches('details') && event.target.open) {
        loadHelpDetail(event.target);
      }
    }, true);
  }

  function init() {
    if (!documentRef) return;

    bindDetailLoad();
    loadHelpArticles();
  }

  return {
    normalizeList: normalizeList,
    buildHelpItem: buildHelpItem,
    renderHelpArticles: renderHelpArticles,
    init: init
  };
});