import express from 'express';
import cors from 'cors';
import bodyParser from 'body-parser';
import { createRequire } from 'module';
import wgService from './services/wgService.js';
import auth from './middleware/auth.js';

const require = createRequire(import.meta.url);

const app = express();
app.use(cors());
app.use(bodyParser.json({ limit: '2mb' }));

// Health
app.get('/api/health', (_req, res) => {
  res.json({ ok: true });
});

// Auth
app.post('/api/login', (req, res) => {
  const ADMIN_PASSWORD = process.env.ADMIN_PASSWORD;
  const { password } = req.body || {};
  if (!ADMIN_PASSWORD) {
    return res.status(500).json({ error: '未配置 ADMIN_PASSWORD 环境变量' });
  }
  if (password !== ADMIN_PASSWORD) {
    return res.status(401).json({ error: '密码错误' });
  }
  const token = auth.issueToken();
  res.json({ token });
});

// 保护以下接口
app.use('/api', auth.verifyToken);

// Server config
app.get('/api/server/config', async (req, res) => {
  try {
    const iface = req.query.interface || 'wg0';
    const content = await wgService.readServerConfig(iface);
    res.json({ interface: iface, content });
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

app.put('/api/server/config', async (req, res) => {
  try {
    const { interface: iface = 'wg0', content } = req.body || {};
    if (typeof content !== 'string') {
      return res.status(400).json({ error: 'content must be string' });
    }
    const result = await wgService.writeServerConfig(iface, content);
    res.json({ ok: true, backupPath: result.backupPath, path: result.path });
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

// Server control
app.post('/api/server/control', async (req, res) => {
  try {
    const { interface: iface = 'wg0', action } = req.body || {};
    if (!['start', 'stop', 'restart'].includes(action)) {
      return res.status(400).json({ error: 'action must be start|stop|restart' });
    }
    const output = await wgService.controlService(iface, action);
    res.json({ ok: true, output });
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

// Server status
app.get('/api/server/status', async (req, res) => {
  try {
    const iface = req.query.interface || 'wg0';
    const status = await wgService.getStatus(iface);
    res.json(status);
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

// Keys
app.post('/api/keys/generate', async (req, res) => {
  try {
    const { type = 'pair' } = req.body || {};
    if (type === 'pair') {
      const pair = await wgService.generateKeyPair();
      res.json(pair);
    } else if (type === 'psk') {
      const psk = await wgService.generatePresharedKey();
      res.json({ presharedKey: psk });
    } else {
      res.status(400).json({ error: 'type must be pair|psk' });
    }
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

// Client config
app.post('/api/clients/generate', async (req, res) => {
  try {
    const {
      interface: iface = 'wg0',
      name,
      clientAddress, // optional; auto-assign if omitted
      dns = '1.1.1.1',
      allowedIps = '0.0.0.0/0, ::/0',
      keepalive = 25,
      endpointHost,
      endpointPort,
      usePresharedKey = false,
    } = req.body || {};

    if (!name) return res.status(400).json({ error: 'name is required' });
    if (!endpointHost || !endpointPort) {
      return res.status(400).json({ error: 'endpointHost and endpointPort are required' });
    }

    const result = await wgService.generateClientConfig({
      interfaceName: iface,
      clientName: name,
      clientAddress,
      dns,
      allowedIps,
      keepalive,
      endpointHost,
      endpointPort,
      usePresharedKey,
    });

    // 生成后自动写入服务端Peer
    await wgService.appendPeerToServerConfig({
      interfaceName: iface,
      clientName: name,
      clientPublicKey: result.publicKey,
      clientAddress: result.address,
      presharedKey: result.presharedKey,
      allowedIps,
    });

    res.json(result);
  } catch (err) {
    res.status(500).json({ error: String(err?.message || err) });
  }
});

const PORT = process.env.PORT || 51821;
app.listen(PORT, () => {
  // eslint-disable-next-line no-console
  console.log(`wg-easy backend listening on :${PORT}`);
});