#!/usr/bin/env node
'use strict';

/**
 * 把旧 customer-service-kb/*.md 导入 LibreDesk 帮助中心（文章 + ai_enabled）。
 *
 * 为什么用文章而不是 snippets：
 *  - 只有帮助中心文章能被 AI 引用（[[cite:id]]）
 *  - 会同时进入帮助中心站内搜索
 *
 * 鉴权：用 System 账号登录拿 session + CSRF（不依赖 API key）。
 * 用法：
 *   node scripts/import-kb-helpcenter.js --dry-run
 *   node scripts/import-kb-helpcenter.js
 */

const fs = require('fs');
const path = require('path');

const ROOT = path.resolve(__dirname, '..');
const KB_DIR = '/home/dev/code/crm/crm-ai-demo/customer-service-kb';
const DRY = process.argv.includes('--dry-run');

// 文件 -> collection（跳过 site-map：导航类内容会污染 FAQ 向量检索）
const COLLECTIONS = [
  { file: '01-registration-account.md', slug: 'registration', name: 'Registration & Account' },
  { file: '02-ordering.md', slug: 'ordering', name: 'Ordering' },
  { file: '03-pre-order.md', slug: 'pre-order', name: 'Pre-order' },
  { file: '04-payment-vat-invoice.md', slug: 'payment', name: 'Payment, VAT & Invoices' },
  { file: '05-shipping-delivery.md', slug: 'shipping', name: 'Shipping & Delivery' },
  { file: '06-returns-refunds.md', slug: 'returns', name: 'Returns & Refunds' },
  { file: '07-factory-direct.md', slug: 'factory-direct', name: 'Factory-Direct' },
  { file: '09-membership-rewards.md', slug: 'membership', name: 'Membership & Rewards' },
  { file: '10-products-and-jewelry-care.md', slug: 'products', name: 'Products & Jewelry Care' },
];

const HELP_CENTER = {
  name: 'Yehwang Help Center',
  slug: 'yehwang-help',
  page_title: 'Yehwang Help Center',
  meta_description: 'FAQ for Yehwang wholesale customers: ordering, payment, shipping, returns and more.',
  default_locale: 'en',
  allowed_locales: ['en'],
  template: 'classic',
};

function loadEnv() {
  const out = {};
  for (const line of fs.readFileSync(path.join(ROOT, '.env'), 'utf8').split('\n')) {
    const t = line.trim();
    if (!t || t.startsWith('#')) continue;
    const eq = t.indexOf('=');
    if (eq < 0) continue;
    let v = t.slice(eq + 1).trim();
    if ((v.startsWith('"') && v.endsWith('"')) || (v.startsWith("'") && v.endsWith("'"))) v = v.slice(1, -1);
    out[t.slice(0, eq).trim()] = v;
  }
  return out;
}

// ---------------------------------------------------------------- markdown -> html
function escapeHtml(s) {
  return s
    .replace(/&(?!(amp|lt|gt|quot|#\d+);)/g, '&amp;')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;');
}

function inline(s) {
  let t = escapeHtml(s);
  t = t.replace(/`([^`]+)`/g, '<code>$1</code>');
  t = t.replace(/\*\*([^*]+)\*\*/g, '<strong>$1</strong>');
  t = t.replace(/\[([^\]]+)\]\((https?:\/\/[^)\s]+)\)/g, '<a href="$2">$1</a>');
  return t;
}

function answerToHtml(md) {
  const lines = md.replace(/\r\n/g, '\n').split('\n');
  const blocks = [];
  let para = [];
  let list = null; // { ordered, items }

  const flushPara = () => {
    if (para.length) {
      blocks.push(`<p>${inline(para.join(' '))}</p>`);
      para = [];
    }
  };
  const flushList = () => {
    if (list) {
      const tag = list.ordered ? 'ol' : 'ul';
      blocks.push(`<${tag}>` + list.items.map((i) => `<li>${inline(i)}</li>`).join('') + `</${tag}>`);
      list = null;
    }
  };

  for (const raw of lines) {
    const line = raw.trim();
    if (!line) {
      flushPara();
      flushList();
      continue;
    }
    const ol = line.match(/^(\d+)[.)]\s+(.*)$/);
    const ul = line.match(/^[-*+]\s+(.*)$/);
    if (ol) {
      flushPara();
      if (!list || !list.ordered) { flushList(); list = { ordered: true, items: [] }; }
      list.items.push(ol[2]);
    } else if (ul) {
      flushPara();
      if (!list || list.ordered) { flushList(); list = { ordered: false, items: [] }; }
      list.items.push(ul[1]);
    } else {
      flushList();
      para.push(line);
    }
  }
  flushPara();
  flushList();
  return blocks.join('\n');
}

function parseFrontmatter(text) {
  const m = text.match(/^---\n([\s\S]*?)\n---\n?/);
  if (!m) return { meta: {}, body: text };
  const meta = {};
  for (const line of m[1].split('\n')) {
    const kv = line.match(/^([a-z_]+):\s*(.*)$/);
    if (kv) meta[kv[1]] = kv[2];
  }
  return { meta, body: text.slice(m[0].length) };
}

function parseSections(body) {
  const parts = body.split(/^### Q:\s*/m).slice(1);
  return parts.map((p) => {
    const lines = p.split('\n');
    const question = lines.shift().trim();
    const answerMd = lines.join('\n').trim();
    return { question, answerMd };
  }).filter((s) => s.question && s.answerMd);
}

function normalizeQ(q) {
  return q.toLowerCase().replace(/[^a-z0-9]+/g, ' ').trim();
}

function plainText(html) {
  return html.replace(/<[^>]+>/g, ' ').replace(/&amp;/g, '&').replace(/\s+/g, ' ').trim();
}

// ---------------------------------------------------------------- HTTP client
function createClient(baseURL) {
  const cookies = new Map();
  let csrf = '';

  function cookieHeader() {
    return [...cookies.entries()].map(([k, v]) => `${k}=${v}`).join('; ');
  }

  function storeCookies(res) {
    const list = typeof res.headers.getSetCookie === 'function'
      ? res.headers.getSetCookie()
      : [res.headers.get('set-cookie')].filter(Boolean);
    for (const c of list) {
      const [pair] = c.split(';');
      const eq = pair.indexOf('=');
      if (eq > 0) {
        const k = pair.slice(0, eq).trim();
        const v = pair.slice(eq + 1).trim();
        cookies.set(k, v);
        if (k === 'csrf_token') csrf = v;
      }
    }
  }

  async function req(method, urlPath, body) {
    const headers = { Accept: 'application/json' };
    if (cookies.size) headers.Cookie = cookieHeader();
    if (body !== undefined) headers['Content-Type'] = 'application/json';
    if (csrf && method !== 'GET' && method !== 'HEAD') headers['X-CSRFTOKEN'] = csrf;

    const res = await fetch(baseURL + urlPath, {
      method,
      headers,
      body: body === undefined ? undefined : JSON.stringify(body),
    });
    storeCookies(res);
    const text = await res.text();
    let json = null;
    try { json = text ? JSON.parse(text) : null; } catch { /* ignore */ }
    if (!res.ok) {
      const msg = json && json.message ? json.message : text.slice(0, 300);
      throw new Error(`${method} ${urlPath} -> HTTP ${res.status}: ${msg}`);
    }
    return json;
  }

  return { req, get: (p) => req('GET', p), post: (p, b) => req('POST', p, b), put: (p, b) => req('PUT', p, b) };
}

function asData(json) {
  if (!json) return null;
  return json.data !== undefined ? json.data : json;
}

// ---------------------------------------------------------------- main
async function main() {
  const env = loadEnv();
  const base = (env.LIBREDESK_BASE_URL || 'http://192.168.31.61:9000').replace(/\/+$/, '');
  const email = env.LIBREDESK_SYSTEM_EMAIL || 'System';
  const password = env.LIBREDESK_SYSTEM_USER_PASSWORD;
  if (!password) throw new Error('缺少 LIBREDESK_SYSTEM_USER_PASSWORD');

  // 1. 解析 KB
  const plans = [];
  const seen = new Set();
  let totalQuestions = 0;
  for (const col of COLLECTIONS) {
    const file = path.join(KB_DIR, col.file);
    if (!fs.existsSync(file)) { console.warn(`跳过缺失文件 ${col.file}`); continue; }
    const { body } = parseFrontmatter(fs.readFileSync(file, 'utf8'));
    const sections = parseSections(body);
    const articles = [];
    for (const s of sections) {
      const key = normalizeQ(s.question);
      if (!key || seen.has(key)) continue;
      seen.add(key);
      const html = answerToHtml(s.answerMd);
      const text = plainText(html);
      articles.push({
        title: s.question.replace(/\s+/g, ' ').trim(),
        content: `<h2>${escapeHtml(s.question)}</h2>\n${html}`,
        excerpt: text.slice(0, 200),
      });
    }
    totalQuestions += articles.length;
    plans.push({ ...col, articles });
  }

  console.log(`解析完成：${plans.length} 个 collection，${totalQuestions} 篇文章（已全局去重）`);
  for (const p of plans) console.log(`  - ${p.name}: ${p.articles.length}`);
  if (DRY) return;

  // 2. 登录
  const c = createClient(base);
  await c.post('/api/v1/auth/login', { email, password });
  console.log(`登录成功：${email}`);

  // 3. 帮助中心
  const existingHC = asData(await c.get('/api/v1/help-centers')) || [];
  let hc = existingHC.find((x) => x.slug === HELP_CENTER.slug);
  if (!hc) {
    hc = asData(await c.post('/api/v1/help-centers', {
      ...HELP_CENTER,
      allowed_locales: HELP_CENTER.allowed_locales,
      theme: {},
    }));
    console.log(`创建帮助中心 #${hc.id} ${hc.slug}`);
  } else {
    console.log(`复用帮助中心 #${hc.id} ${hc.slug}`);
  }

  // 4. collections + articles
  const existingCols = asData(await c.get(`/api/v1/help-centers/${hc.id}/collections`)) || [];
  // 注意：服务端会用 name 生成 slug（重名时追加 -2），因此按 name 匹配而不是 slug。
  const normName = (s) => String(s || '').trim().toLowerCase();
  const colByName = new Map(existingCols.map((x) => [normName(x.name), x]));

  // 现有文章标题（按 collection 分组，避免重复导入）
  const treeResp = asData(await c.get(`/api/v1/help-centers/${hc.id}/tree`)) || {};
  const titlesByColId = new Map();
  const walk = (nodes) => {
    for (const n of nodes || []) {
      const set = titlesByColId.get(n.id) || new Set();
      for (const a of n.articles || []) set.add(normalizeQ(a.title));
      titlesByColId.set(n.id, set);
      walk(n.children);
    }
  };
  walk(treeResp.tree);

  let createdCols = 0, createdArticles = 0, skipped = 0;
  let order = 0;
  for (const plan of plans) {
    order += 10;
    let col = colByName.get(normName(plan.name));
    if (!col) {
      col = asData(await c.post(`/api/v1/help-centers/${hc.id}/collections`, {
        slug: plan.slug,
        locale: 'en',
        name: plan.name,
        description: '',
        icon: '',
        sort_order: order,
        is_published: true,
      }));
      createdCols++;
      colByName.set(normName(plan.name), col);
    }

    const existingTitles = titlesByColId.get(col.id) || new Set();
    let added = 0;
    let i = 0;
    for (const art of plan.articles) {
      i += 1;
      if (existingTitles.has(normalizeQ(art.title))) { skipped++; continue; }
      await c.post(`/api/v1/collections/${col.id}/articles`, {
        locale: 'en',
        title: art.title,
        content: art.content,
        excerpt: art.excerpt,
        sort_order: i * 10,
        status: 'published',
        ai_enabled: true,
      });
      added++;
      createdArticles++;
    }
    console.log(`  ${plan.name}: +${added}`);
  }

  console.log(`\n完成：新建 collection ${createdCols}，文章 ${createdArticles}，跳过已存在 ${skipped}`);
  console.log('注意：向量索引依赖 AI Provider 的 embedding 配置；配置后会自动 reindex。');
}

main().catch((err) => {
  console.error('[import-kb]', err.message);
  process.exit(1);
});