import express from 'express';
import { getDraftForUser, saveDraftForUser } from './db.ts';
import { loginUser, logoutSession, registerUser, requireAuth, resolveSession } from './auth.ts';
import type { DraftPayload } from './types.ts';

const app = express();
const port = Number(process.env.PORT || 8787);

app.use(express.json({ limit: '10mb' }));

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

app.post('/api/auth/register', (req, res) => {
  const username = String(req.body?.username || '').trim();
  const password = String(req.body?.password || '');

  if (username.length < 3 || password.length < 6) {
    res.status(400).json({ error: '账号至少 3 位，密码至少 6 位' });
    return;
  }

  try {
    const result = registerUser(username, password);
    res.json(result);
  } catch (error) {
    res.status(400).json({ error: error instanceof Error ? error.message : '注册失败' });
  }
});

app.post('/api/auth/login', (req, res) => {
  const username = String(req.body?.username || '').trim();
  const password = String(req.body?.password || '');

  if (!username || !password) {
    res.status(400).json({ error: '请输入账号和密码' });
    return;
  }

  try {
    const result = loginUser(username, password);
    res.json(result);
  } catch (error) {
    res.status(401).json({ error: error instanceof Error ? error.message : '登录失败' });
  }
});

app.get('/api/auth/session', (req, res) => {
  const header = req.headers.authorization || '';
  const token = header.startsWith('Bearer ') ? header.slice(7) : '';
  if (!token) {
    res.status(401).json({ error: '未登录' });
    return;
  }

  const user = resolveSession(token);
  if (!user) {
    res.status(401).json({ error: '登录已失效' });
    return;
  }

  res.json({ user });
});

app.post('/api/auth/logout', requireAuth, (req, res) => {
  if (req.authToken) {
    logoutSession(req.authToken);
  }
  res.json({ ok: true });
});

app.get('/api/draft/current', requireAuth, (req, res) => {
  const draft = getDraftForUser(req.authUser!.id);
  res.json({ draft });
});

app.post('/api/draft/current', requireAuth, (req, res) => {
  const payload = req.body?.draft as DraftPayload | undefined;
  if (!payload || typeof payload !== 'object') {
    res.status(400).json({ error: '草稿内容无效' });
    return;
  }

  const draft = saveDraftForUser(req.authUser!.id, payload);
  res.json({ draft });
});

app.listen(port, '127.0.0.1', () => {
  console.log(`ScriptFlow server listening on http://127.0.0.1:${port}`);
});