const express = require('express');
const session = require('express-session');
const bcrypt = require('bcryptjs');
const multer = require('multer');
const rateLimit = require('express-rate-limit');
const crypto = require('crypto');
const fs = require('fs');
const path = require('path');
const net = require('net');
const https = require('https');
const WebSocket = require('ws'); // 需要 npm install ws（版本^8即可）

const PORT = process.env.PORT || 3210;
// 127.0.0.1 by default: on a VPS, Nginx fronts this with TLS and is the only
// thing that should be reachable from outside. On the old local-Windows setup
// this was 0.0.0.0 for LAN access; set HOST=0.0.0.0 explicitly if you still
// need that. COOKIE_SECURE should be "true" once you're behind real HTTPS.
const HOST = process.env.HOST || '127.0.0.1';
const COOKIE_SECURE = process.env.COOKIE_SECURE === 'true';
const DATA_FILE = path.join(__dirname, 'data.json');
const PID_FILE = path.join(__dirname, 'server.pid');
const FRONTEND_DIST = path.join(__dirname, '..', 'frontend', 'dist');
const UPLOADS_DIR = path.join(__dirname, 'uploads');
const AUTH_FILE = path.join(__dirname, 'auth.json');
const DEFAULT_USERNAME = 'admin';
const DEFAULT_PASSWORD = 'admin123';
// AI批量导入解析时，PDF渲染成图片/OCR用的临时文件放在这里，而不是系统的 os.tmpdir()（一般是
// /tmp）——有些VPS/容器环境会把 /tmp 挂载成只读或者单独的受限分区，直接用系统临时目录在这类
// 环境下会导致 mkdtempSync 抛出 EROFS 之类的错误，而且这个调用当时没被 try/catch 包住，会
// 直接让整个Node进程崩溃。用应用自己目录下这个文件夹，保证和 uploads/ 一样一定可读写。
const OCR_TMP_ROOT = path.join(__dirname, 'tmp-ocr');

if (!fs.existsSync(UPLOADS_DIR)) fs.mkdirSync(UPLOADS_DIR, { recursive: true });
if (!fs.existsSync(OCR_TMP_ROOT)) fs.mkdirSync(OCR_TMP_ROOT, { recursive: true });

/* --------------------------------- auth ---------------------------------- */

function loadAuth() {
  if (!fs.existsSync(AUTH_FILE)) {
    const auth = { username: DEFAULT_USERNAME, passwordHash: bcrypt.hashSync(DEFAULT_PASSWORD, 10) };
    fs.writeFileSync(AUTH_FILE, JSON.stringify(auth, null, 2), 'utf8');
    return auth;
  }
  try {
    return JSON.parse(fs.readFileSync(AUTH_FILE, 'utf8'));
  } catch (e) {
    const auth = { username: DEFAULT_USERNAME, passwordHash: bcrypt.hashSync(DEFAULT_PASSWORD, 10) };
    fs.writeFileSync(AUTH_FILE, JSON.stringify(auth, null, 2), 'utf8');
    return auth;
  }
}
function saveAuth(auth) {
  fs.writeFileSync(AUTH_FILE, JSON.stringify(auth, null, 2), 'utf8');
}

/* ------------------------------ secret / crypto -------------------------- */
// Used to encrypt the DeepSeek API key (and anything else sensitive) at
// rest, so it isn't sitting around the filesystem as plain text.

const SECRET_KEY_FILE = path.join(__dirname, '.secret-key');
function getSecretKey() {
  if (!fs.existsSync(SECRET_KEY_FILE)) {
    const key = crypto.randomBytes(32);
    fs.writeFileSync(SECRET_KEY_FILE, key.toString('base64'), { encoding: 'utf8', mode: 0o600 });
    return key;
  }
  return Buffer.from(fs.readFileSync(SECRET_KEY_FILE, 'utf8').trim(), 'base64');
}
const SECRET_KEY = getSecretKey();

function encrypt(text) {
  if (!text) return '';
  const iv = crypto.randomBytes(12);
  const cipher = crypto.createCipheriv('aes-256-gcm', SECRET_KEY, iv);
  const encrypted = Buffer.concat([cipher.update(text, 'utf8'), cipher.final()]);
  const tag = cipher.getAuthTag();
  return Buffer.concat([iv, tag, encrypted]).toString('base64');
}
function decrypt(b64) {
  if (!b64) return '';
  try {
    const buf = Buffer.from(b64, 'base64');
    const iv = buf.subarray(0, 12);
    const tag = buf.subarray(12, 28);
    const encrypted = buf.subarray(28);
    const decipher = crypto.createDecipheriv('aes-256-gcm', SECRET_KEY, iv);
    decipher.setAuthTag(tag);
    return Buffer.concat([decipher.update(encrypted), decipher.final()]).toString('utf8');
  } catch (e) {
    return '';
  }
}

/* --------------------------------- AI config ------------------------------ */

const AI_CONFIG_FILE = path.join(__dirname, 'ai-config.json');
// Lets you point this at a different OpenAI-compatible endpoint if needed
// (e.g. testing against a mock server); defaults to the real DeepSeek API.
const DEEPSEEK_API_BASE = process.env.DEEPSEEK_API_BASE || 'https://api.deepseek.com';

function loadAiConfig() {
  try {
    const raw = JSON.parse(fs.readFileSync(AI_CONFIG_FILE, 'utf8'));
    return { apiKey: decrypt(raw.apiKeyEnc || '') };
  } catch (e) {
    return { apiKey: '' };
  }
}
function saveAiConfig(apiKey) {
  fs.writeFileSync(AI_CONFIG_FILE, JSON.stringify({ apiKeyEnc: encrypt(apiKey) }, null, 2), 'utf8');
}

/* ------------------------------ Telegram config ---------------------------- */
// Just My Socks 线路异常报警用——bot token 用和AI Key一样的AES-256-GCM加密方式落盘，
// chat_id 不算敏感信息，明文存就行。

const TELEGRAM_CONFIG_FILE = path.join(__dirname, 'telegram-config.json');

function loadTelegramConfig() {
  try {
    const raw = JSON.parse(fs.readFileSync(TELEGRAM_CONFIG_FILE, 'utf8'));
    return { botToken: decrypt(raw.botTokenEnc || ''), chatId: raw.chatId || '' };
  } catch (e) {
    return { botToken: '', chatId: '' };
  }
}
function saveTelegramConfig(botToken, chatId) {
  fs.writeFileSync(TELEGRAM_CONFIG_FILE, JSON.stringify({ botTokenEnc: encrypt(botToken), chatId }, null, 2), 'utf8');
}
async function sendTelegramMessage(text) {
  const cfg = loadTelegramConfig();
  if (!cfg.botToken || !cfg.chatId) throw new Error('Telegram未配置');
  const res = await fetch(`https://api.telegram.org/bot${cfg.botToken}/sendMessage`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ chat_id: cfg.chatId, text, parse_mode: 'HTML' }),
  });
  const data = await res.json().catch(() => ({}));
  if (!data.ok) throw new Error(data.description || 'Telegram发送失败');
  return data;
}

/* ------------------------------ JMS 线路监控 ------------------------------- */
// 普通TCP连通性测试——SS / VMess / VLESS Reality 用这个就够，它们直连IP，没有CDN挡在前面。
function tcpCheck(host, port, timeoutMs = 6000) {
  return new Promise((resolve) => {
    const socket = new net.Socket();
    let done = false;
    const finish = (ok) => { if (!done) { done = true; socket.destroy(); resolve(ok); } };
    socket.setTimeout(timeoutMs);
    socket.once('connect', () => finish(true));
    socket.once('timeout', () => finish(false));
    socket.once('error', () => finish(false));
    socket.connect(Number(port) || 443, host);
  });
}

// VLESS+WS+TLS+CDN 专属深度检测：CDN边缘节点本身几乎永远在线，单纯TCP连通测不出"源站已经挂了"，
// 所以这里改用两个更有信号量的信号——
// 1) Cloudflare的520/521/522/523/524是"源站不可达"专属状态码，能连上CDN但源站挂了会明确返回这几个码；
// 2) 再做一次真正的WebSocket握手，直接对应Xray/sing-box监听WS的那一层，比单看状态码更准。
// 两个都过才算正常。
function httpStatusCheck(host, wsPath, timeoutMs = 8000) {
  return new Promise((resolve) => {
    const req = https.request({
      hostname: host, port: 443, path: wsPath || '/', method: 'GET', timeout: timeoutMs,
      headers: { 'User-Agent': 'Mozilla/5.0' },
    }, (res) => {
      res.resume();
      const badGateway = [520, 521, 522, 523, 524].includes(res.statusCode);
      resolve(!badGateway);
    });
    req.on('timeout', () => { req.destroy(); resolve(false); });
    req.on('error', () => resolve(false));
    req.end();
  });
}
function wsHandshakeCheck(host, wsPath, timeoutMs = 8000) {
  return new Promise((resolve) => {
    let done = false;
    let ws;
    const finish = (ok) => {
      if (done) return;
      done = true;
      try { ws && ws.terminate(); } catch (e) {}
      resolve(ok);
    };
    try {
      ws = new WebSocket(`wss://${host}${wsPath || '/'}`, { handshakeTimeout: timeoutMs });
      ws.on('open', () => finish(true));
      ws.on('unexpected-response', () => finish(false));
      ws.on('error', () => finish(false));
    } catch (e) {
      finish(false);
    }
    setTimeout(() => finish(false), timeoutMs + 500);
  });
}

async function checkLineConnectivity(line) {
  if (line.protocol === 'vless-cdn') {
    const [httpOk, wsOk] = await Promise.all([
      httpStatusCheck(line.addr, line.ws_path),
      wsHandshakeCheck(line.addr, line.ws_path),
    ]);
    return httpOk && wsOk;
  }
  return tcpCheck(line.addr, line.port);
}

// 后台定时巡检：每 JMS_CHECK_INTERVAL_MS 跑一轮，只在状态发生变化（正常↔异常）时才发Telegram，
// 不会每次检测都刷屏。直接读写 crm:jmsLines 这个通用存储key（前端也是存在这里）。
const JMS_CHECK_INTERVAL_MS = 10 * 60 * 1000; // 10分钟
async function runJmsMonitorCycle() {
  const data = readData();
  const raw = data['crm:jmsLines'];
  if (!raw) return;
  let lines;
  try { lines = JSON.parse(raw); } catch (e) { return; }
  if (!Array.isArray(lines) || !lines.length) return;

  for (const line of lines) {
    try {
      const ok = await checkLineConnectivity(line);
      const newStatus = ok ? 'normal' : 'abnormal';
      if (line.monitorStatus && line.monitorStatus !== newStatus) {
        const name = line.name || line.addr;
        const msg = newStatus === 'abnormal'
          ? `⚠️ <b>${name}</b> 检测异常，无法连接\n协议：${line.protocol}\n地址：${line.addr}:${line.port}`
          : `✅ <b>${name}</b> 已恢复正常\n协议：${line.protocol}\n地址：${line.addr}:${line.port}`;
        sendTelegramMessage(msg).catch(() => {}); // Telegram没配置/发送失败都不影响检测本身
      }
      line.monitorStatus = newStatus;
      line.lastChecked = Date.now();
    } catch (e) {
      // 检测本身出错（异常里的异常），跳过这条不写状态，下一轮再试
    }
  }
  data['crm:jmsLines'] = JSON.stringify(lines);
  writeData(data);
}
setInterval(() => { runJmsMonitorCycle().catch(() => {}); }, JMS_CHECK_INTERVAL_MS);
setTimeout(() => { runJmsMonitorCycle().catch(() => {}); }, 60 * 1000); // 启动1分钟后先跑一轮

const REGION_LABELS = {
  africa: 'Africa', middle_east: 'Middle East', australia: 'Australia/Oceania',
  europe: 'Europe', sea: 'Southeast Asia', other: 'Other',
};

function buildCustomerContext(c) {
  const lines = [];
  lines.push(`Company: ${c.company || '(unknown / not on file)'}`);
  if (c.contact) lines.push(`Contact person: ${c.contact}`);
  const place = [c.country, REGION_LABELS[c.region]].filter(Boolean).join(', ');
  if (place) lines.push(`Location: ${place}`);
  if (c.productLines && c.productLines.length) lines.push(`Product interest: ${c.productLines.join(', ')}`);
  if (c.intendedModel || c.intendedQty) {
    lines.push(`Specific model interest: ${c.intendedModel || '(model unspecified)'}${c.intendedQty ? `, quantity: ${c.intendedQty}` : ''}`);
  }
  if (c.lastContact) lines.push(`Last contact date: ${c.lastContact}`);
  if (c.notes) lines.push(`Background research on this customer: ${c.notes}`);
  if (c.tags) lines.push(`Additional remarks: ${c.tags}`);
  if (c.isVip) lines.push('This is a VIP / priority customer — extra attentive tone.');
  if (c.hasOrdered) lines.push('This customer has already placed an order before — this follow-up is with an existing buyer, not a cold lead.');
  return lines.join('\n');
}

async function callDeepSeek(apiKey, messages, opts) {
  const { maxTokens = 600, temperature = 0.7, model = 'deepseek-v4-flash' } = opts || {};
  const resp = await fetch(`${DEEPSEEK_API_BASE}/chat/completions`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      Authorization: `Bearer ${apiKey}`,
    },
    body: JSON.stringify({
      model,
      messages,
      temperature,
      max_tokens: maxTokens,
    }),
  });
  if (!resp.ok) {
    const errText = await resp.text().catch(() => '');
    throw new Error(`DeepSeek API error ${resp.status}: ${errText.slice(0, 200)}`);
  }
  const data = await resp.json();
  const choice = data.choices && data.choices[0];
  const content = choice && choice.message && choice.message.content;
  if (!content) {
    const reason = choice && choice.finish_reason ? `（finish_reason: ${choice.finish_reason}）` : '';
    throw new Error(`DeepSeek API returned an empty response${reason}`);
  }
  return content;
}

// 空响应这种问题偶发性比较大（有时候纯粹是API抽风），重试一次往往就好了；
// 其他类型的错误（比如key不对、额度用完）重试也没用，直接抛出不浪费时间
async function callDeepSeekWithRetry(apiKey, messages, opts, retries = 1) {
  let lastErr;
  for (let attempt = 0; attempt <= retries; attempt++) {
    try {
      return await callDeepSeek(apiKey, messages, opts);
    } catch (e) {
      lastErr = e;
      if (!/empty response/i.test(e.message) || attempt === retries) throw e;
    }
  }
  throw lastErr;
}

// 从DeepSeek返回的内容里提取JSON——模型有时会用```json代码块包一层，或者前后带几句解释文字，
// 这里做宽松解析：优先找代码块，找不到就找第一个 { 或 [ 开始的内容。
// 返回 { data, truncated }：如果完整JSON解析失败（常见原因是撞到了max_tokens，数组还没写完
// 就被截断了），会尝试抢救出前面已经完整生成的那些顶层对象，丢弃最后一个写了一半的，这样至少
// 能拿到部分结果，而不是整批因为最后一个字符缺失就全部作废。
function extractJson(content) {
  const fenced = content.match(/```(?:json)?\s*([\s\S]*?)```/i);
  const raw = fenced ? fenced[1] : content;
  const start = raw.search(/[\[{]/);
  if (start === -1) throw new Error('AI返回内容里没有找到JSON');
  const trimmed = raw.slice(start);

  try {
    return { data: JSON.parse(trimmed), truncated: false };
  } catch (e) {
    const salvaged = salvageTruncatedJsonArray(trimmed);
    if (salvaged !== null) return { data: salvaged, truncated: true };
    throw new Error(`AI返回的内容不是完整的JSON，解析失败：${e.message}`);
  }
}

// 只处理"最外层是数组"的截断抢救：逐字符扫描（跳过字符串内部的引号/转义），每次遇到顶层元素
// 完整闭合（深度归零）就记一下位置，最后从抢救到的最后一个完整位置那里把数组截断重新拼上 ]。
function salvageTruncatedJsonArray(text) {
  const t = text.trim();
  if (!t.startsWith('[')) return null;
  let depth = 0;
  let lastCompleteEnd = -1;
  let inString = false;
  let escapeNext = false;
  for (let i = 1; i < t.length; i++) {
    const ch = t[i];
    if (inString) {
      if (escapeNext) escapeNext = false;
      else if (ch === '\\') escapeNext = true;
      else if (ch === '"') inString = false;
      continue;
    }
    if (ch === '"') { inString = true; continue; }
    if (ch === '{' || ch === '[') depth++;
    else if (ch === '}' || ch === ']') {
      depth--;
      if (depth === 0 && ch === '}') lastCompleteEnd = i; // 顶层数组里某个对象完整闭合了
    }
  }
  if (lastCompleteEnd === -1) return null;
  try {
    return JSON.parse(t.slice(0, lastCompleteEnd + 1) + ']');
  } catch (e) {
    return null;
  }
}

/* ------------------------------ data file ------------------------------ */

function readData() {
  try {
    return JSON.parse(fs.readFileSync(DATA_FILE, 'utf8'));
  } catch (e) {
    return {};
  }
}

function writeData(data) {
  // write to a temp file then rename, avoids corrupting data.json if the
  // process is killed mid-write
  const tmp = DATA_FILE + '.tmp';
  fs.writeFileSync(tmp, JSON.stringify(data, null, 2), 'utf8');
  fs.renameSync(tmp, DATA_FILE);
}

// only allow simple ids (our customer ids are like "c_169..._ab12c"),
// this keeps the upload path from ever escaping the uploads/ folder
function safeId(id) {
  return /^[A-Za-z0-9_-]+$/.test(id) ? id : null;
}

/* --------------------------------- app ---------------------------------- */

const app = express();

// behind Nginx, Express needs this to read X-Forwarded-* correctly —
// otherwise req.ip is always Nginx's own address (breaks rate limiting)
// and the "secure" cookie flag can't tell the request was HTTPS.
app.set('trust proxy', 1);

app.use(express.json({ limit: '10mb' }));
app.use(session({
  secret: crypto.randomBytes(32).toString('hex'),
  resave: false,
  saveUninitialized: false,
  cookie: {
    httpOnly: true,
    sameSite: 'lax',
    secure: COOKIE_SECURE,
    maxAge: 30 * 24 * 60 * 60 * 1000, // 30 days
  },
}));

function requireAuth(req, res, next) {
  if (req.session && req.session.authed) return next();
  res.status(401).json({ error: 'not authenticated' });
}

const loginLimiter = rateLimit({
  windowMs: 15 * 60 * 1000,
  max: 5,
  standardHeaders: true,
  legacyHeaders: false,
  message: { error: 'too many login attempts, please try again in a few minutes' },
});

/* -------------------------------- auth api ------------------------------- */

app.post('/api/auth/login', loginLimiter, (req, res) => {
  const body = req.body || {};
  const username = body.username || '';
  const password = body.password || '';
  const auth = loadAuth();
  if (username === auth.username && bcrypt.compareSync(password, auth.passwordHash)) {
    req.session.authed = true;
    req.session.username = username;
    return res.json({ ok: true, username });
  }
  res.status(401).json({ error: 'invalid credentials' });
});

app.post('/api/auth/logout', (req, res) => {
  if (req.session) {
    req.session.destroy(() => res.json({ ok: true }));
  } else {
    res.json({ ok: true });
  }
});

app.get('/api/auth/check', (req, res) => {
  const authed = !!(req.session && req.session.authed);
  res.json({ authed, username: authed ? req.session.username : null });
});

app.post('/api/auth/change-password', requireAuth, (req, res) => {
  const body = req.body || {};
  const currentPassword = body.currentPassword || '';
  const newPassword = body.newPassword || '';
  const auth = loadAuth();
  if (!bcrypt.compareSync(currentPassword, auth.passwordHash)) {
    return res.status(400).json({ error: 'current password is incorrect' });
  }
  if (newPassword.length < 4) {
    return res.status(400).json({ error: 'new password is too short' });
  }
  auth.passwordHash = bcrypt.hashSync(newPassword, 10);
  saveAuth(auth);
  res.json({ ok: true });
});

/* ------------------------------ storage api ------------------------------ */

app.get('/api/storage/:key', requireAuth, (req, res) => {
  const data = readData();
  const key = req.params.key;
  if (!(key in data)) return res.status(404).json({ error: 'not found' });
  res.json({ value: data[key] });
});

app.put('/api/storage/:key', requireAuth, (req, res) => {
  const data = readData();
  data[req.params.key] = req.body.value;
  writeData(data);
  res.json({ ok: true });
});

/* --------------------------------- ai api --------------------------------- */

app.get('/api/ai-config', requireAuth, (req, res) => {
  const cfg = loadAiConfig();
  res.json({ hasKey: !!cfg.apiKey });
});

app.put('/api/ai-config', requireAuth, (req, res) => {
  const apiKey = ((req.body && req.body.apiKey) || '').trim();
  if (!apiKey) return res.status(400).json({ error: 'apiKey is required' });
  saveAiConfig(apiKey);
  res.json({ ok: true });
});

app.delete('/api/ai-config', requireAuth, (req, res) => {
  try { fs.unlinkSync(AI_CONFIG_FILE); } catch (e) {}
  res.json({ ok: true });
});

app.post('/api/ai-config/test', requireAuth, async (req, res) => {
  const cfg = loadAiConfig();
  if (!cfg.apiKey) return res.status(400).json({ error: 'no API key configured' });
  try {
    const content = await callDeepSeek(cfg.apiKey, [{ role: 'user', content: 'Reply with exactly: OK' }]);
    res.json({ ok: true, reply: content.trim() });
  } catch (e) {
    res.status(400).json({ error: e.message });
  }
});

/* ------------------------------ Telegram api ------------------------------- */

app.get('/api/telegram-config', requireAuth, (req, res) => {
  const cfg = loadTelegramConfig();
  res.json({ hasToken: !!cfg.botToken, chatId: cfg.chatId || '' });
});

app.put('/api/telegram-config', requireAuth, (req, res) => {
  const botToken = ((req.body && req.body.botToken) || '').trim();
  const chatId = ((req.body && req.body.chatId) || '').trim();
  if (!botToken || !chatId) return res.status(400).json({ error: 'botToken和chatId都需要填写' });
  saveTelegramConfig(botToken, chatId);
  res.json({ ok: true });
});

app.delete('/api/telegram-config', requireAuth, (req, res) => {
  try { fs.unlinkSync(TELEGRAM_CONFIG_FILE); } catch (e) {}
  res.json({ ok: true });
});

app.post('/api/telegram-config/test', requireAuth, async (req, res) => {
  try {
    await sendTelegramMessage('✅ 客户档案系统：Telegram通知测试成功，配置没问题。');
    res.json({ ok: true });
  } catch (e) {
    res.status(400).json({ error: e.message });
  }
});

/* --------------------------------- JMS api --------------------------------- */

const jmsCheckLimiter = rateLimit({
  windowMs: 60 * 1000, max: 20, standardHeaders: true, legacyHeaders: false,
  message: { error: '检测太频繁了，请稍等一下再试' },
});

// 手动"立即检测"——对单条线路马上跑一次连通性检测；如果状态发生了变化，也会像后台巡检一样发Telegram
app.post('/api/jms/check-line', requireAuth, jmsCheckLimiter, async (req, res) => {
  const line = req.body && req.body.line;
  if (!line || !line.addr) return res.status(400).json({ error: '线路信息不完整' });
  try {
    const ok = await checkLineConnectivity(line);
    const newStatus = ok ? 'normal' : 'abnormal';
    if (line.monitorStatus && line.monitorStatus !== newStatus) {
      const name = line.name || line.addr;
      const msg = newStatus === 'abnormal'
        ? `⚠️ <b>${name}</b> 检测异常，无法连接\n协议：${line.protocol}\n地址：${line.addr}:${line.port}`
        : `✅ <b>${name}</b> 已恢复正常\n协议：${line.protocol}\n地址：${line.addr}:${line.port}`;
      sendTelegramMessage(msg).catch(() => {});
    }
    res.json({ ok: true, status: newStatus, checkedAt: Date.now() });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// 代为请求JMS订阅地址，解析 Subscription-Userinfo 响应头拿到流量信息——
// 浏览器直接fetch会被CORS挡住，服务器端发请求没有这个限制
app.post('/api/jms/fetch-traffic', requireAuth, async (req, res) => {
  const url = ((req.body && req.body.subscriptionUrl) || '').trim();
  if (!url) return res.status(400).json({ error: '请先填写标准订阅地址' });
  let parsed;
  try {
    parsed = new URL(url);
    if (!/^https?:$/.test(parsed.protocol)) throw new Error('invalid protocol');
  } catch (e) {
    return res.status(400).json({ error: '订阅地址格式不对' });
  }
  try {
    const response = await fetch(url, { headers: { 'User-Agent': 'Mozilla/5.0' } });
    const header = response.headers.get('subscription-userinfo');
    if (!header) return res.json({ ok: false, error: '这个订阅地址没有返回流量信息（Subscription-Userinfo），可能服务商不支持或者地址不对' });
    const info = {};
    header.split(';').forEach(part => {
      const [k, v] = part.trim().split('=');
      if (k && v !== undefined) info[k.trim()] = Number(v.trim());
    });
    res.json({
      ok: true,
      upload: info.upload || 0,
      download: info.download || 0,
      total: info.total || 0,
      expire: info.expire || null,
    });
  } catch (e) {
    res.status(400).json({ error: '获取订阅信息失败：' + e.message });
  }
});


const aiLimiter = rateLimit({
  windowMs: 10 * 60 * 1000,
  max: 30,
  standardHeaders: true,
  legacyHeaders: false,
  message: { error: 'too many AI requests, please slow down' },
});

app.post('/api/ai/draft', requireAuth, aiLimiter, async (req, res) => {
  const body = req.body || {};
  const customerId = body.customerId;
  const channel = body.channel;
  if (!customerId || !['email', 'whatsapp'].includes(channel)) {
    return res.status(400).json({ error: 'invalid request' });
  }
  const cfg = loadAiConfig();
  if (!cfg.apiKey) return res.status(400).json({ error: 'DeepSeek API key not configured' });

  const data = readData();
  let customers = [];
  try { customers = JSON.parse(data['crm:customers'] || '[]'); } catch (e) {}
  const customer = customers.find((c) => c.id === customerId);
  if (!customer) return res.status(404).json({ error: 'customer not found' });

  const context = buildCustomerContext(customer);
  const systemPrompt = 'You are a sales assistant helping a B2B export salesperson at a Chinese power-equipment company (UPS systems, rectifiers, solar inverters, battery storage) write natural, professional follow-up outreach to overseas customers. Always write in English. Never sound like a generic template, reference specifics from the customer info given. Output only the requested content, with no meta-commentary, explanations, or markdown formatting.';

  const userPrompt = channel === 'email'
    ? `Customer info:\n${context}\n\nWrite a short, warm but professional follow-up email to this customer. Respond in EXACTLY this format with no extra text:\nSUBJECT: <subject line>\nBODY:\n<email body, 3-5 short paragraphs max, sign off with "[Your name]">`
    : `Customer info:\n${context}\n\nWrite a short, casual WhatsApp message to check in with this customer (2-4 sentences, friendly tone, no formal greeting like "Dear", a light emoji is fine if it feels natural). Respond with ONLY the message text, nothing else.`;

  try {
    const content = await callDeepSeek(cfg.apiKey, [
      { role: 'system', content: systemPrompt },
      { role: 'user', content: userPrompt },
    ]);
    if (channel === 'email') {
      const subjectMatch = content.match(/SUBJECT:\s*(.+)/i);
      const bodyMatch = content.match(/BODY:\s*([\s\S]*)/i);
      res.json({
        subject: subjectMatch ? subjectMatch[1].trim() : 'Following up',
        body: bodyMatch ? bodyMatch[1].trim() : content.trim(),
      });
    } else {
      res.json({ body: content.trim() });
    }
  } catch (e) {
    res.status(502).json({ error: e.message });
  }
});

/* --------------------------- ai catalog import --------------------------- */
// 上传一份/多份PDF或图片形式的产品目录（可能包含多个型号），做OCR文字识别后交给
// DeepSeek解析成结构化的产品字段数组，前端拿到后先给用户一个预览/确认页面，
// 用户确认后再批量建档。
//
// 实测发现很多正式排版的产品目录PDF（比如设计软件导出的宣传册）整页都是图片/矢量
// 图形，没有可提取的文字层，所以这里统一走"渲染成图片 + OCR"这条路，而不是直接
// 提取PDF文字——这样PDF和图片两种输入方式可以复用同一套OCR逻辑。
//
// 依赖：
//  1. npm包 tesseract.js（纯JS+WASM，不需要装系统级OCR程序，但第一次识别时会从
//     jsdelivr CDN下载语言包，VPS需要能访问外网）
//  2. 系统程序 poppler-utils，只有上传PDF时才需要，用来把PDF每页渲染成图片：
//     apt install -y poppler-utils

const { execFile } = require('child_process');
const Tesseract = require('tesseract.js');

const uploadMemory = multer({
  storage: multer.memoryStorage(),
  limits: { fileSize: 20 * 1024 * 1024, files: 30 }, // 20MB/文件，最多30个文件
});

// 把一份PDF的每一页渲染成PNG图片（用poppler-utils的pdftoppm），返回图片路径数组
function renderPdfToImages(pdfBuffer, tmpDir) {
  return new Promise((resolve, reject) => {
    const pdfPath = path.join(tmpDir, 'source.pdf');
    fs.writeFileSync(pdfPath, pdfBuffer);
    const outPrefix = path.join(tmpDir, 'page');
    execFile('pdftoppm', ['-png', '-r', '200', pdfPath, outPrefix], (err) => {
      if (err) {
        return reject(new Error(
          `PDF转图片失败，请确认服务器已安装 poppler-utils（SSH执行：apt install -y poppler-utils）：${err.message}`
        ));
      }
      const files = fs.readdirSync(tmpDir)
        .filter((f) => f.startsWith('page') && f.endsWith('.png'))
        .sort()
        .map((f) => path.join(tmpDir, f));
      resolve(files);
    });
  });
}

// 复用同一个OCR worker，避免每次请求都重新初始化/重新下载语言包
let ocrWorkerPromise = null;
function getOcrWorker() {
  if (!ocrWorkerPromise) {
    ocrWorkerPromise = Tesseract.createWorker('eng+chi_sim').catch((e) => {
      ocrWorkerPromise = null; // 初始化失败下次重试，不要把失败结果缓存住
      throw e;
    });
  }
  return ocrWorkerPromise;
}

async function ocrImages(imagePaths) {
  const worker = await getOcrWorker();
  const parts = [];
  for (const p of imagePaths) {
    const { data } = await worker.recognize(p);
    if (data && data.text) parts.push(data.text.trim());
  }
  return parts.join('\n\n--- 下一页 ---\n\n').trim();
}

const CATALOG_PARSE_SYSTEM_PROMPT = `你是一个电力设备（UPS/逆变器/储能电池等）产品资料的结构化提取助手。
用户会给你一份产品目录/规格书经OCR识别出的文字内容（可能包含多个不同型号的产品，每个产品通常有自己的Specifications表格；
OCR识别可能有少量错字或格式错乱，请结合上下文合理判断）。
你的任务：识别文本里有几个不同型号的产品，为每一个产品提取字段，严格按下面的JSON schema输出一个数组，每个元素是一个产品对象：

【特别注意"系列名"和"具体型号"的区别】很多规格表会在标题里写"XX系列智能在线式UPS"这种大标题（这是整个系列的统称，
不是某个产品的型号），真正的具体型号一定在表格里"型号"那一行/列里能找到（比如ATP-10K/CRT、ATP-20K/CRT这种）。
绝对不能把标题里的系列泛称当成name字段的值去输出一条"合并"的记录——表格里"型号"那一行有几个不同的型号名称，
就必须输出几条独立的产品记录，哪怕它们之间只有额定功率/尺寸/净重这几个数字不一样、其他参数全部相同，也不能因为
"看起来很像"就合并成一条、更不能因为拿不准就用系列名代替。如果OCR识别出来的文字比较模糊、型号名称对不齐对应的
数值，宁可把能确定的字段填全、拿不准的字段留空，也不要瞎猜合并。

【特别注意"型号(L)"这种带括号的写法】规格表的型号列里如果出现类似"MS1000(L)"这种写法，代表这里其实是两个型号，
要拆成两条独立的产品记录输出，不能只输出一条：
- 不带L后缀的（如MS1000）是标准机型：machineVariant填"标准机型"
- 带L后缀的（如MS1000L）是长延时机型：machineVariant填"长延时机型"
这两条记录的输入/输出/保护/警告/接口/环境这些参数完全共用同一份数据，只有 batterySpec（电池型号和数量）、
chargeCurrent（充电电流）、dimensions（尺寸）、netWeight（净重）这几项不同——严格按表格里"Standard Model/标准机型"
和"Long-run Model/长延机型"这两个子分类去分别取值，标准机型用Standard Model那部分数据，长延时机型用Long-run Model那部分数据。
如果某个型号在"Standard Model"部分对应列是NA或空、只有"Long-run Model"部分有数据，说明这个型号本身就是长延机型
（哪怕名字里没有明显的"(L)"标记也一样），直接当长延时机型处理，不要再凭空拆出一个去掉后缀的"标准版"；反过来如果只有
"Standard Model"部分有数据、"Long-run Model"部分是NA或空，说明这个型号只有标准机型，也不要凭空造一个带L的长延版本。

【特别注意"UPS配套锂电池系统"这类产品的两段式结构】这类产品（储能电池大类下）的规格表通常明确分成两个区域，
一个是"模块/Module"（单个电池模块本身的参数），一个是"锂电池系统柜/电池系统柜"（整个机柜/整套系统的参数），
跟模块化UPS"功率模块 + UPS机柜"是同样的两段式逻辑。这两个区域各自包含好几项参数，请务必把两个区域的每一项
都完整提取，绝对不能只提取其中一个区域、漏掉另一个区域——常见的漏提取情况是：只填了型号/循环寿命/通信接口/
保护功能这种"看起来一目了然"的字段，却漏掉了电芯类型、放电倍率、充电倍率、模块最大能量、模块输出功率、
模块尺寸、模块重量这些"模块"区域的参数，或者漏掉了电池最大能量、运行温度、相对湿度、颜色、系统柜尺寸、
系统柜重量、海拔、自放电率这些"锂电池系统柜"区域的参数。提取完之后自己检查一遍：below schema里所有标注了
"UPS配套锂电池系统专属"的字段，只要OCR文字里出现了对应的数值，就必须填上，不能遗漏。

{
  "name": "型号，比如 POE-532E",
  "brand": "品牌中文名，从厂家名称/logo文字判断；看不出就填空字符串",
  "category": "产品大类中文名，从这些里选最接近的：UPS不间断电源 / 光伏逆变器 / 储能电池；不确定就填 UPS不间断电源",
  "type": "细分品类中文名。如果是这种带USB/DC/POE多路直流输出口的小型UPS，填 迷你UPS；如果是没有LCD/LED显示、简单的家用小型UPS(型号通常带Offline/后备式字样)，填 离线式UPS；如果标注了Line-Interactive/互动式，填 在线互动式UPS；如果是True double-conversion/真双变换在线式且明确标注了机架安装、2U/3U/4U这种机架单位、rack-mount字样，填 机架式UPS；如果同样是True double-conversion/真双变换在线式，但看起来是塔式/立式外观（没有明确的机架安装标注），填 在线式高频UPS；这两个类型区分不确定的话，优先填 在线式高频UPS，用户在确认预览阶段还可以手动改；如果产品大类是储能电池，且规格表明确分成"模块"和"电池系统柜/电池柜"两级、给UPS配套用的中大功率锂电池系统，填 UPS配套锂电池系统；如果产品大类是光伏逆变器，且明确标注了Hybrid/On-Off-Grid/混网/既能并网又能离网这种既能接市电又能脱网独立供电的能力（通常还带电池输入参数），填 太阳能混网逆变器；储能电池大类下其他常见值：铅酸电池、磷酸铁锂电池；光伏逆变器大类下其他常见值：并网/离网逆变器；UPS不间断电源大类下其他常见值：高频塔式UPS、工频UPS、模块化UPS；不确定就留空字符串",
  "machineVariant": "标准机型 或 长延时机型：按前面【型号(L)拆分规则】判断，标准机型（内置电池）填\"标准机型\"，长延时机型（外接电池，通常型号带L后缀）填\"长延时机型\"；不属于这种拆分场景的常规产品，不确定就填标准机型",
  "powerOrCapacity": "非UPS大类的功率/容量；如果是迷你UPS，这里填输出功率（如 17W）；如果是离线式UPS/在线互动式UPS/机架式UPS，这里填Capacity/容量（如 400VA/240W）；其他情况不确定就填空字符串",
  "voltage": "如果是迷你UPS，这里填输入电压，如 100~240Vac/50-60Hz；如果是离线式UPS/在线互动式UPS/机架式UPS，这个字段不用填（用下面的inputVoltage/outputVoltage代替）；其他情况填常规电压参数，不确定填空字符串",
  "ratedPower": "", "ratedPowerUnit": "VA", "powerFactor": "",
  "outputPortCount": "迷你UPS专属：这个型号有几路输出口，数字字符串，如 4，不适用就填空字符串",
  "outputPortTypes": "迷你UPS专属：输出口类型数组，只能用这些token：USB、DC、DC1、DC2、DC3、POE、Type-C、DC interface、POE interface；不适用就填空数组",
  "outputPorts": "迷你UPS专属：数组，每项 {\\"type\\":\\"USB\\",\\"voltage\\":\\"5Vdc\\",\\"current\\":\\"3.0A\\"}，和outputPortTypes一一对应；不适用就填空数组",
  "inputVoltage": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Input Voltage/输入电压(或Nominal Voltage/标称电压)，如 110V/120Vac or 220V/230Vac；不适用就填空字符串",
  "inputVoltageRange": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Voltage range/输入电压范围，如 162-268Vac/170-280Vac；不适用就填空字符串",
  "inputFrequency": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Frequency/输入频率(范围)，如 50/60Hz（Auto sensing）或 40Hz~70Hz；不适用就填空字符串",
  "outputVoltage": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS/太阳能混网逆变器专属：Output Voltage/输出电压，如 110V/120Vac or 220V/230Vac；不适用就填空字符串",
  "outputVoltageRange": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：输出电压范围(或Voltage Regulation/电压调整率)，如 ±10% 或 ±1%；不适用就填空字符串",
  "transferTime": "离线式UPS/在线互动式UPS专属：Transfer time/转换时间，如 Typical 2-8ms, 13ms max；机架式UPS这里填Inverter to Bypass那个转换时间（AC to Battery那个用下面的transferTimeAcToBattery）；不适用就填空字符串",
  "waveform": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Wave form/波形，如 Simulated Sine Wave 或 pure sine wave；不适用就填空字符串",
  "batteryVoltage": "离线式UPS/在线互动式UPS/太阳能混网逆变器专属：Battery Voltage/电池电压，如 12V 或 24V；不适用就填空字符串",
  "chargeCurrent": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Charge current/充电电流，如 1A；如果涉及【型号(L)拆分规则】，要按标准机型/长延时机型分别取Standard Model或Long-run Model那部分的数据；不适用就填空字符串",
  "frequencyRangeBatteryMode": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Frequency range(battery mode)/频率范围(电池模式)，如 50/60Hz±1Hz；不适用就填空字符串",
  "chargeTime": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Charge time/充电时间(或Typical Recharge Time)，如 8 hours recover to 90% capacity；不适用就填空字符串",
  "lcdDisplay": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：LCD display/LCD显示(或LCD Panel)能展示哪些信息，把原文整段抄下来，如 UPS status, Load level, Battery level, Input/Output voltage, Discharge timer, and Fault conditions；不适用就填空字符串",
  "ledDisplay": "离线式UPS/在线互动式UPS专属：LED display/LED显示，把各个模式对应的灯光颜色都列出来（一行一条，用\\n分隔），如 AC mode: Green lighting\\nBattery mode: Yellow lighting\\nFault: Red lighting；不适用就填空字符串",
  "fullProtection": "离线式UPS/在线互动式UPS专属：Full Protection/全面保护，如 Discharge, Short circuit and overload protection；不适用就填空字符串",
  "alarmInfo": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Alarm/警告提示，把电池模式/低电量/过载/故障这几种蜂鸣提示规律都列出来（一行一条，用\\n分隔），如 Battery mode: Sounding every 10 seconds\\nLow battery: Sounding every second\\nOverload: Sounding every 0.5 seconds\\nFault: Continuously sounding；不适用就填空字符串",
  "interfacePort": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS专属：Interface/控制管理接口说明，如 USB/RS232 port(optional), Support windows xp/vista, windows 7/8/11 and MAC，或 Smart RS-232/USB, Supports Windows 2000/2003/XP/Vista/2008, Windows 7/8, Linux, Unix, and MAC；不适用就填空字符串",
  "humidity": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS/UPS配套锂电池系统/太阳能混网逆变器专属：Humidity/湿度(或相对湿度)，如 0-90% RH@0-40°C(Non-condensing) 或 5%~95%（无凝露）；不适用就填空字符串",
  "noiseLevel": "离线式UPS/在线互动式UPS/机架式UPS/在线式高频UPS/太阳能混网逆变器专属：Noise Level/噪音，如 Less than 40dB(1m spacing)；不适用就填空字符串",
  "phase": "机架式UPS/在线式高频UPS专属：Phase/相数，如 1-phase input/1-phase output 或 3-phase input/1-phase output；不适用就填空字符串",
  "inputPowerFactor": "机架式UPS/在线式高频UPS专属：输入侧Power Factor/功率因数，如 ≥0.99@100% load；不适用就填空字符串",
  "transferTimeAcToBattery": "机架式UPS/在线式高频UPS专属：Transfer Time - AC Mode to Battery Mode/转换时间(市电到电池)，如 0ms；不适用就填空字符串",
  "currentCrestRatio": "机架式UPS/在线式高频UPS专属：Current Crest Ratio/峰值电流比，如 3:1；不适用就填空字符串",
  "harmonicDistortion": "机架式UPS/在线式高频UPS专属：Harmonic Distortion/谐波失真，如 ≤3% THD (Linear Load), ≤5% THD (Non-linear Load)；不适用就填空字符串",
  "efficiencyAcMode": "机架式UPS/在线式高频UPS专属：Efficiency - AC Mode/效率(市电模式)，如 88%；不适用就填空字符串",
  "efficiencyBatteryMode": "机架式UPS/在线式高频UPS专属：Efficiency - Battery Mode/效率(电池模式)，如 83%；不适用就填空字符串",
  "chargingVoltage": "机架式UPS/在线式高频UPS专属：Charging Voltage/充电电压，如 27.4VDC±1%；如果涉及【型号(L)拆分规则】，要按标准机型/长延时机型分别取Standard Model或Long-run Model那部分的数据；不适用就填空字符串",
  "optionalSnmp": "机架式UPS/在线式高频UPS专属：Optional SNMP/可选SNMP，如 Power management from SNMP manager and web browser；不适用就填空字符串",
  "outputPowerFactor": "在线式高频UPS/太阳能混网逆变器专属：Output Power Factor/输出功率因数，如 0.9 或 1；不适用就填空字符串",
  "parallelUnits": "在线式高频UPS专属：Number of Parallel Units/可并联台数，如 Not supported，或具体可并联数量；不适用就填空字符串",
  "overload": "在线式高频UPS专属：Overload/过载保护，如 105%-125% 6-25s; >150% 200ms；不适用就填空字符串",
  "moduleType": "UPS配套锂电池系统专属：模块类型，如 长延时型；不适用就填空字符串",
  "moduleCapacity": "UPS配套锂电池系统专属：模块额定容量(Ah)，如 100；不适用就填空字符串",
  "cellType": "UPS配套锂电池系统专属：电芯类型，如 磷酸铁锂电池（LFP）；不适用就填空字符串",
  "moduleVoltage": "UPS配套锂电池系统专属：模块额定电压(V)，如 51.2；不适用就填空字符串",
  "dischargeRate": "UPS配套锂电池系统专属：放电倍率(C)，如 2；不适用就填空字符串",
  "chargeRate": "UPS配套锂电池系统专属：充电倍率(C)，如 1；不适用就填空字符串",
  "moduleMaxEnergy": "UPS配套锂电池系统专属：模块最大能量(kWh)，如 5.12；不适用就填空字符串",
  "moduleOutputPower": "UPS配套锂电池系统专属：模块输出功率(kW)，如 10.24；不适用就填空字符串",
  "moduleDimensions": "UPS配套锂电池系统专属：模块尺寸(mm)，如 440*440*131；不适用就填空字符串",
  "moduleWeight": "UPS配套锂电池系统专属：模块重量(kg)，如 43±2；不适用就填空字符串",
  "cabinetMaxEnergy": "UPS配套锂电池系统专属：电池系统柜最大能量(kWh)，如 40.96；不适用就填空字符串",
  "cabinetRatedVoltage": "UPS配套锂电池系统专属：额定输出电压(V)，如 409.6/±204.8/460.8/512/±256/563.2/614.4/±307.2；不适用就填空字符串",
  "cycleLife": "UPS配套锂电池系统专属：循环寿命，如 5000次@50%DOD；不适用就填空字符串",
  "commInterface": "UPS配套锂电池系统专属：通信接口，如 LAN/CAN/RS485/干接点；不适用就填空字符串",
  "protectionFunctions": "UPS配套锂电池系统/太阳能混网逆变器专属：保护功能，如 过充、过放、过温、过流、短路等；不适用就填空字符串",
  "operatingTemp": "UPS配套锂电池系统/太阳能混网逆变器专属：运行温度，如 0~40℃(推荐20~25℃运行)；不适用就填空字符串",
  "color": "UPS配套锂电池系统专属：颜色，如 RAL9004；不适用就填空字符串",
  "cabinetDimensions": "UPS配套锂电池系统专属：电池系统柜尺寸(mm)，如 600×850×2000；不适用就填空字符串",
  "cabinetWeight": "UPS配套锂电池系统专属：电池系统柜重量(kg)，如 544±10（8模组配置）；不适用就填空字符串",
  "altitude": "UPS配套锂电池系统/太阳能混网逆变器专属：海拔(m)，如 ≤4000（>2000降额使用）；不适用就填空字符串",
  "selfDischargeRate": "UPS配套锂电池系统专属：自放电率，如 <5%（环境温度0～30℃/30天）；不适用就填空字符串",
  "batterySpec": "电池数量和容量/电池型号和数量，如 2200mAh*4 或 12V4.5AH*1；机架式UPS这里可以把Battery Type和Numbers合并成一句话，如 12V/9AH x2；如果这个型号涉及【型号(L)拆分规则】，要按这条记录是标准机型还是长延时机型，分别取Standard Model或Long-run Model那部分的数据，不确定填空字符串",
  "dimensions": "尺寸(mm)，如 175*105*30；如果涉及【型号(L)拆分规则】，同样要按标准机型/长延时机型分别取对应子分类的数据，不确定填空字符串",
  "netWeight": "净重(kg)，如 0.4；如果涉及【型号(L)拆分规则】，同样要按标准机型/长延时机型分别取对应子分类的数据，不确定填空字符串",
  "batteryType": "太阳能混网逆变器专属：电池类型，如 Lithium or lead acid battery；不适用就填空字符串",
  "maxChargingVoltage": "太阳能混网逆变器专属：最大充电电压，如 ≤60 (Configurable)；不适用就填空字符串",
  "maxChargeDischargeCurrent": "太阳能混网逆变器专属：最大充放电电流，如 190A；不适用就填空字符串",
  "maxDcInputPower": "太阳能混网逆变器专属：最大直流输入功率，如 16000W；不适用就填空字符串",
  "maxDcInputVoltage": "太阳能混网逆变器专属：最大直流输入电压，如 1000V；不适用就填空字符串",
  "mpptVoltageRange": "太阳能混网逆变器专属：MPPT工作电压范围，如 200~800V；不适用就填空字符串",
  "startingVoltage": "太阳能混网逆变器专属：启动电压，如 150V；不适用就填空字符串",
  "maxInputCurrent": "太阳能混网逆变器专属：最大输入电流，如 18/18A；不适用就填空字符串",
  "mpptNumber": "太阳能混网逆变器专属：MPPT路数，如 2；不适用就填空字符串",
  "onGridMaxApparentPower": "太阳能混网逆变器专属：并网最大输出视在功率，如 8800W；不适用就填空字符串",
  "ratedOutputFrequency": "太阳能混网逆变器专属：额定输出频率，如 50/60Hz；不适用就填空字符串",
  "onGridMaxOutputCurrent": "太阳能混网逆变器专属：并网最大输出电流，如 13.3A；不适用就填空字符串",
  "offGridRatedApparentPower": "太阳能混网逆变器专属：离网额定输出视在功率，如 8000W；不适用就填空字符串",
  "offGridMaxApparentPower": "太阳能混网逆变器专属：离网最大输出视在功率，如 >200%,15sec；不适用就填空字符串",
  "offGridMaxOutputCurrent": "太阳能混网逆变器专属：离网最大输出电流，如 13.3A；不适用就填空字符串",
  "efficiencyMppt": "太阳能混网逆变器专属：最大效率(MPPT)，如 98%；不适用就填空字符串",
  "efficiencyMax": "太阳能混网逆变器专属：最大效率，如 94.5%；不适用就填空字符串",
  "efficiencyEurope": "太阳能混网逆变器专属：欧洲效率，如 97.5%；不适用就填空字符串",
  "storageTemp": "太阳能混网逆变器专属：存储温度，如 -30~65°C；不适用就填空字符串",
  "cooling": "太阳能混网逆变器专属：散热方式，如 Intelligent forced air cooling；不适用就填空字符串",
  "protectionClass": "太阳能混网逆变器专属：防护等级，如 IP66；不适用就填空字符串",
  "topology": "太阳能混网逆变器专属：拓扑结构，如 HF isolation(Battery side)；不适用就填空字符串",
  "safetyStandard": "太阳能混网逆变器专属：安规/EMC标准，把原文列出来的标准编号都抄下来，如 NB/T32004-2018, IEC62109, IEC61000；不适用就填空字符串",
  "gridStandard": "太阳能混网逆变器专属：并网标准，如 IEC61727, EN50549-1, VDE-4105；不适用就填空字符串",
  "otherStandard": "太阳能混网逆变器专属：其他标准，如 IEC61683, IEC62116, EN50530；不适用就填空字符串",
  "sellingPoints": "如果原文里除了技术规格表之外，还有一些营销性质的卖点/主要特点描述（通常是几条带图标或项目符号的短句，比如\"Up-to-36A maximum input current\"、\"IP66 design\"这种面向客户宣传的亮点，不是纯技术参数表格里的数值），把这些提取出来，每条一行，用\\n分隔；如果原文只有技术规格表、没有这种营销卖点描述，就填空字符串，不要自己瞎编凑数",
  "notes": "其他有用但上面字段装不下的信息，一两句话，没有就填空字符串"
}

只返回一个JSON数组，不要有任何解释文字、不要用markdown代码块包裹、不要省略任何一个识别到的型号。`;

app.post('/api/ai/parse-catalog', requireAuth, aiLimiter, (req, res) => {
  uploadMemory.array('files', 30)(req, res, async (err) => {
    if (err) return res.status(400).json({ error: err.message });
    if (!req.files || !req.files.length) return res.status(400).json({ error: 'no file received' });
    const cfg = loadAiConfig();
    if (!cfg.apiKey) return res.status(400).json({ error: 'DeepSeek API key not configured' });

    // 用户可以提前告诉我们这批文件大概是什么大类/品牌/细分品类，这样AI不用自己瞎猜这几个字段，
    // 只需要专心提取每个型号的具体规格参数；提供了的话，最后会直接用这几个值覆盖AI的猜测结果。
    const hintCategory = (req.body && req.body.hintCategory || '').trim();
    const hintBrand = (req.body && req.body.hintBrand || '').trim();
    const hintType = (req.body && req.body.hintType || '').trim();

    let tmpDir;
    try {
      tmpDir = fs.mkdtempSync(path.join(OCR_TMP_ROOT, 'catalog-ocr-'));
      const imagePaths = [];
      const htmlTextParts = []; // HTML文件不用OCR，直接读文字内容（保留表格标签结构，AI能看懂rowspan这种分组关系）
      for (const file of req.files) {
        const isPdf = (file.mimetype || '').includes('pdf') || file.originalname.toLowerCase().endsWith('.pdf');
        const isImage = (file.mimetype || '').startsWith('image/');
        const isHtml = (file.mimetype || '').includes('html') || /\.html?$/i.test(file.originalname);
        if (isPdf) {
          const pdfSubDir = fs.mkdtempSync(path.join(tmpDir, 'pdf-'));
          const pages = await renderPdfToImages(file.buffer, pdfSubDir);
          imagePaths.push(...pages);
        } else if (isImage) {
          const ext = path.extname(file.originalname) || '.png';
          const imgPath = path.join(tmpDir, `img_${imagePaths.length}${ext}`);
          fs.writeFileSync(imgPath, file.buffer);
          imagePaths.push(imgPath);
        } else if (isHtml) {
          const raw = file.buffer.toString('utf8');
          // 只去掉 <style>/<script> 这种纯样式/脚本内容（对AI提取参数没用、白白占token），
          // 保留其余全部HTML标签结构——比如 rowspan 属性能直接告诉AI"这几行同属一个分组"，
          // 这比OCR识别出来的一堆无结构纯文字准确得多。
          const cleaned = raw
            .replace(/<style[\s\S]*?<\/style>/gi, '')
            .replace(/<script[\s\S]*?<\/script>/gi, '')
            .trim();
          if (cleaned) htmlTextParts.push(cleaned);
        } else {
          return res.status(400).json({ error: `不支持的文件类型：${file.originalname}（只支持PDF、图片或HTML）` });
        }
      }

      const ocrText = imagePaths.length ? await ocrImages(imagePaths) : '';
      const text = [ocrText, ...htmlTextParts].filter(Boolean).join('\n\n--- 下一份文件 ---\n\n');
      if (!text) return res.status(400).json({ error: '没有识别/读取到任何文字内容，请确认文件清晰、内容完整' });

      // 识别出来的文本太长就截断，避免超出模型输出预算；产品目录类文档核心信息通常靠前
      const MAX_CHARS = 24000;
      const clippedText = text.length > MAX_CHARS ? text.slice(0, MAX_CHARS) : text;

      const hintLines = [];
      if (hintCategory) hintLines.push(`产品大类：${hintCategory}`);
      if (hintBrand) hintLines.push(`品牌：${hintBrand}`);
      if (hintType) hintLines.push(`细分品类：${hintType}`);
      const userContent = hintLines.length
        ? `【用户已确认以下信息，直接使用，不用自己判断】\n${hintLines.join('\n')}\n\n【以下是文档内容，可能是OCR识别结果、也可能是直接提取的HTML源码——HTML里的表格标签结构（比如rowspan）请重点利用，能帮助你判断字段的分组归属】\n${clippedText}`
        : clippedText;

      const content = await callDeepSeekWithRetry(cfg.apiKey, [
        { role: 'system', content: CATALOG_PARSE_SYSTEM_PROMPT },
        { role: 'user', content: userContent },
      ], { maxTokens: 16000, temperature: 0.2 });
      const { data: products, truncated } = extractJson(content);
      if (!Array.isArray(products)) throw new Error('AI没有返回预期的数组格式，请重试');
      // 双保险：即使AI没完全听话，这里直接强制覆盖，保证和用户预选的一致
      const finalProducts = products.map((p) => ({
        ...p,
        category: hintCategory || p.category,
        brand: hintBrand || p.brand,
        type: hintType || p.type,
      }));
      res.json({ products: finalProducts, ocrTextLength: text.length, truncated });
    } catch (e) {
      const hint = /empty response/i.test(e.message)
        ? '（重试后仍然失败，可能是一次上传的文件太多导致AI输出内容超长；建议减少单次上传的数量，比如分成2-3批，每批3-5张）'
        : '';
      res.status(502).json({ error: `${e.message}${hint}` });
    } finally {
      try { fs.rmSync(tmpDir, { recursive: true, force: true }); } catch (e) {}
    }
  });
});

/* ------------------------------- ai translate ------------------------------ */
// 给前端的翻译词条缓存（存在 crm:translationGlossary 里，走通用storage接口）兜底：
// 前端自己先查缓存，只有命中不了的词才会调这个接口，这里只管翻译，不管缓存的存取。

const LANG_NAMES = { en: 'English', fr: 'French', ru: 'Russian', es: 'Spanish', ar: 'Arabic' };

app.post('/api/ai/translate-terms', requireAuth, aiLimiter, async (req, res) => {
  const body = req.body || {};
  const terms = Array.isArray(body.terms) ? body.terms.filter(t => typeof t === 'string' && t.trim()) : [];
  const targetLang = body.targetLang;
  if (!terms.length || !LANG_NAMES[targetLang]) return res.status(400).json({ error: 'invalid request' });

  const cfg = loadAiConfig();
  if (!cfg.apiKey) return res.status(400).json({ error: 'DeepSeek API key not configured' });

  const systemPrompt = `你是专业的电力设备（UPS/逆变器/储能电池）技术资料翻译。把用户给出的中文技术/业务词汇逐条翻译成${LANG_NAMES[targetLang]}，
要符合这个行业规范书面用词（不要逐字直译），单位符号（如Vdc、A、kg、mm）保持原样不翻译。
严格按JSON对象格式返回：key是原始中文词，value是翻译结果，不要有多余文字、不要用markdown代码块包裹，每个词都必须有对应的翻译。`;
  const userPrompt = JSON.stringify(terms);

  try {
    const content = await callDeepSeekWithRetry(cfg.apiKey, [
      { role: 'system', content: systemPrompt },
      { role: 'user', content: userPrompt },
    ], { maxTokens: 2000, temperature: 0.3 });
    const { data: translations } = extractJson(content);
    res.json({ translations });
  } catch (e) {
    res.status(502).json({ error: e.message });
  }
});

/* ------------------------- communication attachments ------------------------- */

const upload = multer({
  storage: multer.diskStorage({
    destination: (req, file, cb) => {
      const cid = safeId(req.params.customerId);
      if (!cid) return cb(new Error('invalid customer id'));
      const dir = path.join(UPLOADS_DIR, cid);
      fs.mkdirSync(dir, { recursive: true });
      cb(null, dir);
    },
    filename: (req, file, cb) => {
      const ts = Date.now();
      const rand = Math.random().toString(36).slice(2, 8);
      const ext = path.extname(file.originalname).slice(0, 10);
      cb(null, `${ts}_${rand}${ext}`);
    },
  }),
  limits: { fileSize: 25 * 1024 * 1024 }, // 25MB per file
});

app.post('/api/uploads/:customerId', requireAuth, (req, res) => {
  if (!safeId(req.params.customerId)) return res.status(400).json({ error: 'invalid customer id' });
  upload.single('file')(req, res, (err) => {
    if (err) return res.status(400).json({ error: err.message });
    if (!req.file) return res.status(400).json({ error: 'no file received' });
    // multer/busboy 默认按 latin1 解析 multipart 里的文件名字段（这是老版HTTP规范的行为），
    // 但浏览器实际发送的中文文件名是 UTF-8 字节，所以这里要把它从 latin1 转回 UTF-8，
    // 不然中文文件名会变成乱码存进 data.json。
    const originalName = Buffer.from(req.file.originalname, 'latin1').toString('utf8');
    res.json({ fileName: req.file.filename, originalName, size: req.file.size });
  });
});

app.delete('/api/uploads/:customerId/:fileName', requireAuth, (req, res) => {
  const cid = safeId(req.params.customerId);
  const fname = req.params.fileName;
  const isSafeFile = fname && !fname.includes('..') && !fname.includes('/') && !fname.includes('\\');
  if (!cid || !isSafeFile) return res.status(400).json({ error: 'invalid request' });
  fs.unlink(path.join(UPLOADS_DIR, cid, fname), () => {
    // a missing file is also treated as success, so clicking delete twice never errors
    res.json({ ok: true });
  });
});

app.use('/uploads', requireAuth, express.static(UPLOADS_DIR));

app.use(express.static(FRONTEND_DIST));
app.get('*', (req, res) => {
  res.sendFile(path.join(FRONTEND_DIST, 'index.html'));
});

/* ------------------------------- bootstrap ------------------------------ */

loadAuth(); // make sure auth.json exists with default credentials on first run

fs.writeFileSync(PID_FILE, String(process.pid), 'utf8');
process.on('exit', () => {
  try { fs.unlinkSync(PID_FILE); } catch (e) {}
});
process.on('SIGINT', () => process.exit(0));
process.on('SIGTERM', () => process.exit(0));

const server = app.listen(PORT, HOST, () => {
  console.log(`[customer-crm] running at http://${HOST}:${PORT}`);
});

server.on('error', (e) => {
  if (e.code === 'EADDRINUSE') {
    console.log('[customer-crm] another instance is already running on this port, exiting.');
    try { fs.unlinkSync(PID_FILE); } catch (err) {}
    process.exit(0);
  }
  throw e;
});