const jwt = require('jsonwebtoken');
const db = require('../models');
const logger = require('../utils/logger');

const authenticate = async (req, res, next) => {
  try {
    // Get token from header
    const authHeader = req.header('Authorization');

    if (!authHeader || !authHeader.startsWith('Bearer ')) {
      return res.status(401).json({
        success: false,
        message: 'Access denied. No token provided.'
      });
    }

    const token = authHeader.replace('Bearer ', '');

    // Verify token
    const decoded = jwt.verify(token, process.env.JWT_SECRET);

    // Find user
    const user = await db.User.findByPk(decoded.id, {
      attributes: { exclude: ['password'] }
    });

    if (!user) {
      return res.status(401).json({
        success: false,
        message: 'Invalid token. User not found.'
      });
    }

    if (user.status !== 'active') {
      return res.status(401).json({
        success: false,
        message: 'User account is inactive.'
      });
    }

    // Attach user to request
    req.user = user;
    req.token = token;

    next();
  } catch (error) {
    logger.error('Authentication error:', error);

    if (error.name === 'TokenExpiredError') {
      return res.status(401).json({
        success: false,
        message: 'Token expired'
      });
    }

    if (error.name === 'JsonWebTokenError') {
      return res.status(401).json({
        success: false,
        message: 'Invalid token'
      });
    }

    res.status(500).json({
      success: false,
      message: 'Authentication failed'
    });
  }
};

const optionalAuth = async (req, res, next) => {
  try {
    const authHeader = req.header('Authorization');

    if (!authHeader || !authHeader.startsWith('Bearer ')) {
      return next();
    }

    const token = authHeader.replace('Bearer ', '');
    const decoded = jwt.verify(token, process.env.JWT_SECRET);

    const user = await db.User.findByPk(decoded.id, {
      attributes: { exclude: ['password'] }
    });

    if (user && user.status === 'active') {
      req.user = user;
      req.token = token;
    }

    next();
  } catch (error) {
    // If token is invalid/expired, just proceed without user
    next();
  }
};

module.exports = {
  authenticate,
  optionalAuth
};