import express from 'express';
import { AppError } from '../lib/errors.js';
import {
  getSessionForActor,
  parseClientSignIn,
  parseClientSignUp,
  parseStaffPhoneStart,
  parseStaffPhoneVerify,
  signInClient,
  signOutActor,
  signUpClient,
  startStaffPhoneAuth,
  verifyStaffPhoneAuth,
} from '../services/auth-service.js';
import { verifyFirebaseToken } from '../services/firebase-auth.js';

const defaultAuthService = {
  parseClientSignIn,
  parseClientSignUp,
  parseStaffPhoneStart,
  parseStaffPhoneVerify,
  signInClient,
  signOutActor,
  signUpClient,
  startStaffPhoneAuth,
  verifyStaffPhoneAuth,
  getSessionForActor,
};

function getBearerToken(header) {
  if (!header) return null;
  const [scheme, token] = header.split(' ');
  if (!scheme || scheme.toLowerCase() !== 'bearer' || !token) return null;
  return token;
}

async function requireAuth(req, _res, next) {
  try {
    const token = getBearerToken(req.get('Authorization'));
    if (!token) {
      throw new AppError('UNAUTHENTICATED', 'Missing bearer token', 401);
    }

    if (process.env.AUTH_BYPASS === 'true') {
      req.actor = { uid: 'test-user', email: 'test@krow.local', role: 'TEST' };
      return next();
    }

    const decoded = await verifyFirebaseToken(token);
    req.actor = {
      uid: decoded.uid,
      email: decoded.email || null,
      role: decoded.role || null,
    };
    return next();
  } catch (error) {
    if (error instanceof AppError) return next(error);
    return next(new AppError('UNAUTHENTICATED', 'Token verification failed', 401));
  }
}

export function createAuthRouter(options = {}) {
  const router = express.Router();
  const fetchImpl = options.fetchImpl || fetch;
  const authService = options.authService || defaultAuthService;

  router.use(express.json({ limit: '1mb' }));

  router.post('/client/sign-in', async (req, res, next) => {
    try {
      const payload = authService.parseClientSignIn(req.body);
      const session = await authService.signInClient(payload, { fetchImpl });
      return res.status(200).json({
        ...session,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/client/sign-up', async (req, res, next) => {
    try {
      const payload = authService.parseClientSignUp(req.body);
      const session = await authService.signUpClient(payload, { fetchImpl });
      return res.status(201).json({
        ...session,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/staff/phone/start', async (req, res, next) => {
    try {
      const payload = authService.parseStaffPhoneStart(req.body);
      const result = await authService.startStaffPhoneAuth(payload, { fetchImpl });
      return res.status(200).json({
        ...result,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/staff/phone/verify', async (req, res, next) => {
    try {
      const payload = authService.parseStaffPhoneVerify(req.body);
      const session = await authService.verifyStaffPhoneAuth(payload, { fetchImpl });
      return res.status(200).json({
        ...session,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.get('/session', requireAuth, async (req, res, next) => {
    try {
      const session = await authService.getSessionForActor(req.actor);
      return res.status(200).json({
        ...session,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/sign-out', requireAuth, async (req, res, next) => {
    try {
      const result = await authService.signOutActor(req.actor);
      return res.status(200).json({
        ...result,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/client/sign-out', requireAuth, async (req, res, next) => {
    try {
      const result = await authService.signOutActor(req.actor);
      return res.status(200).json({
        ...result,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  router.post('/staff/sign-out', requireAuth, async (req, res, next) => {
    try {
      const result = await authService.signOutActor(req.actor);
      return res.status(200).json({
        ...result,
        requestId: req.requestId,
      });
    } catch (error) {
      return next(error);
    }
  });

  return router;
}