const pool = require('../db');
const { hasPermission, effectivePermissions } = require('../permissions');

async function loadStaffUser(userId) {
  const { rows } = await pool.query(
    `SELECT id, username, role, permissions, is_active
     FROM users WHERE id = $1`,
    [userId]
  );
  if (rows.length === 0) return null;
  const row = rows[0];
  return {
    id: row.id,
    username: row.username,
    role: row.role,
    permissions: row.permissions || [],
    is_active: row.is_active !== false,
  };
}

function attachStaff(req, user) {
  req.curatorUser = {
    id: user.id,
    username: user.username,
    role: user.role,
    permissions: user.permissions,
    is_active: user.is_active,
  };
}

/** Any active staff account (admin or curator). */
async function requireCurator(req, res, next) {
  const userId = req.session?.userId;
  if (!userId) {
    return res.status(401).json({ error: 'Curator login required' });
  }

  try {
    const user = await loadStaffUser(userId);
    if (!user || !user.is_active) {
      req.session.destroy(() => {});
      return res.status(401).json({ error: 'Curator login required' });
    }

    attachStaff(req, user);
    next();
  } catch (err) {
    console.error('Auth middleware error:', err.message);
    res.status(500).json({ error: 'Authentication failed' });
  }
}

/** Active staff with a specific permission (admins always pass). */
function requirePermission(permission) {
  return async (req, res, next) => {
    const userId = req.session?.userId;
    if (!userId) {
      return res.status(401).json({ error: 'Curator login required' });
    }

    try {
      const user = await loadStaffUser(userId);
      if (!user || !user.is_active) {
        req.session.destroy(() => {});
        return res.status(401).json({ error: 'Curator login required' });
      }

      attachStaff(req, user);

      if (!hasPermission(user, permission)) {
        return res.status(403).json({ error: 'Permission denied' });
      }

      next();
    } catch (err) {
      console.error('Auth middleware error:', err.message);
      res.status(500).json({ error: 'Authentication failed' });
    }
  };
}

function staffAuthPayload(user) {
  return {
    role: user.role,
    username: user.username,
    permissions: effectivePermissions(user),
  };
}

module.exports = {
  requireCurator,
  requirePermission,
  loadStaffUser,
  staffAuthPayload,
};