const express = require('express');
const bcrypt = require('bcryptjs');
const { query, formatPrice } = require('../db');
const { getCart, cartCount } = require('../cart');
const { requireAuth } = require('../middleware/auth');
const { requireCookieConsent } = require('../middleware/cookieConsent');
const { ROLES, ROLE_LABELS } = require('../constants/roles');
const { asyncHandler } = require('../utils/asyncHandler');
const { expireOldReservations } = require('../services/reservations');
const webauthn = require('../services/webauthn');

const router = express.Router();

router.use(requireCookieConsent);

router.use((req, res, next) => {
  const cart = getCart(req);
  res.locals.cartCount = cartCount(cart);
  res.locals.formatPrice = formatPrice;
  next();
});

async function loadAccountUser(userId) {
  const { rows } = await query(
    'SELECT id, email, name, role, created_at, passkey_enabled, loyalty_points FROM users WHERE id = $1',
    [userId]
  );
  return rows[0];
}

async function verifyPassword(userId, password) {
  const { rows } = await query('SELECT password_hash FROM users WHERE id = $1', [
    userId,
  ]);
  if (!rows[0]) return false;
  return bcrypt.compareSync(password || '', rows[0].password_hash);
}

function accountRender(res, options) {
  const {
    user,
    orderCount,
    reservations,
    error,
    success,
    activeTab,
    formatPrice,
    passkeys,
    isAdmin,
  } = options;
  res.render('account/index', {
    title: 'Личный кабинет',
    user,
    orderCount,
    reservations: reservations || [],
    passkeys: passkeys || [],
    isAdmin: Boolean(isAdmin),
    roleLabels: ROLE_LABELS,
    formatPrice: formatPrice || res.locals.formatPrice,
    error: error || null,
    success: success || null,
    activeTab: activeTab || 'profile',
  });
}

router.get(
  '/',
  requireAuth,
  asyncHandler(async (req, res) => {
    await expireOldReservations();
    const user = await loadAccountUser(req.session.userId);
    const countResult = await query(
      'SELECT COUNT(*)::int AS n FROM orders WHERE user_id = $1',
      [user.id]
    );

    const { rows: reservations } = await query(
      `SELECT r.*, p.name AS product_name, p.slug AS product_slug, p.price_cents, p.image_url
       FROM reservations r
       JOIN products p ON p.id = r.product_id
       WHERE r.user_id = $1
       ORDER BY r.created_at DESC`,
      [user.id]
    );

    const passkeys = await webauthn.getCredentialsForUser(user.id);

    accountRender(res, {
      user,
      orderCount: countResult.rows[0].n,
      reservations,
      passkeys,
      isAdmin: user.role === ROLES.ADMIN,
      formatPrice,
      success: req.query.success ? decodeURIComponent(String(req.query.success)) : null,
      error: req.query.error ? decodeURIComponent(String(req.query.error)) : null,
      activeTab: req.query.tab || 'profile',
    });
  })
);

router.post(
  '/profile',
  requireAuth,
  asyncHandler(async (req, res) => {
    const name = (req.body.name || '').trim();
    if (!name) {
      return res.redirect('/account?tab=profile&error=' + encodeURIComponent('Укажите имя'));
    }
    await query('UPDATE users SET name = $1 WHERE id = $2', [name, req.session.userId]);
    res.redirect('/account?tab=profile&success=' + encodeURIComponent('Имя обновлено'));
  })
);

router.post(
  '/email',
  requireAuth,
  asyncHandler(async (req, res) => {
    const newEmail = (req.body.email || '').trim().toLowerCase();
    const { current_password } = req.body;

    if (!newEmail) {
      return res.redirect(
        '/account?tab=email&error=' + encodeURIComponent('Укажите новый email')
      );
    }

    const emailRe = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
    if (!emailRe.test(newEmail)) {
      return res.redirect(
        '/account?tab=email&error=' + encodeURIComponent('Некорректный email')
      );
    }

    const user = await loadAccountUser(req.session.userId);
    if (newEmail === user.email) {
      return res.redirect(
        '/account?tab=email&error=' + encodeURIComponent('Это уже ваш текущий email')
      );
    }

    if (!(await verifyPassword(req.session.userId, current_password))) {
      return res.redirect(
        '/account?tab=email&error=' + encodeURIComponent('Неверный текущий пароль')
      );
    }

    try {
      await query('UPDATE users SET email = $1 WHERE id = $2', [
        newEmail,
        req.session.userId,
      ]);
      res.redirect('/account?tab=email&success=' + encodeURIComponent('Email изменён'));
    } catch (err) {
      if (err.code === '23505') {
        return res.redirect(
          '/account?tab=email&error=' + encodeURIComponent('Этот email уже занят')
        );
      }
      throw err;
    }
  })
);

router.post(
  '/password',
  requireAuth,
  asyncHandler(async (req, res) => {
    const { current_password, password, password2 } = req.body;

    if (!(await verifyPassword(req.session.userId, current_password))) {
      return res.redirect(
        '/account?tab=password&error=' + encodeURIComponent('Неверный текущий пароль')
      );
    }

    if (!password || password.length < 6) {
      return res.redirect(
        '/account?tab=password&error=' +
          encodeURIComponent('Новый пароль не менее 6 символов')
      );
    }

    if (password !== password2) {
      return res.redirect(
        '/account?tab=password&error=' + encodeURIComponent('Пароли не совпадают')
      );
    }

    const hash = bcrypt.hashSync(password, 10);
    await query('UPDATE users SET password_hash = $1 WHERE id = $2', [
      hash,
      req.session.userId,
    ]);
    res.redirect('/account?tab=password&success=' + encodeURIComponent('Пароль изменён'));
  })
);

router.post(
  '/passkey/disable',
  requireAuth,
  asyncHandler(async (req, res) => {
    const { current_password } = req.body;
    if (!(await verifyPassword(req.session.userId, current_password))) {
      return res.redirect(
        '/account?tab=passkey&error=' + encodeURIComponent('Неверный пароль')
      );
    }
    await webauthn.disablePasskeys(req.session.userId);
    res.redirect(
      '/account?tab=passkey&success=' + encodeURIComponent('Вход по passkey отключён')
    );
  })
);

router.post(
  '/passkey/credentials/:id/delete',
  requireAuth,
  asyncHandler(async (req, res) => {
    const { current_password } = req.body;
    if (!(await verifyPassword(req.session.userId, current_password))) {
      return res.redirect(
        '/account?tab=passkey&error=' + encodeURIComponent('Неверный пароль')
      );
    }
    const credId = parseInt(req.params.id, 10);
    if (!Number.isFinite(credId)) {
      return res.redirect('/account?tab=passkey&error=' + encodeURIComponent('Некорректный ключ'));
    }
    const ok = await webauthn.deleteCredential(req.session.userId, credId);
    if (!ok) {
      return res.redirect('/account?tab=passkey&error=' + encodeURIComponent('Ключ не найден'));
    }
    res.redirect('/account?tab=passkey&success=' + encodeURIComponent('Passkey удалён'));
  })
);

module.exports = router;