backend/controllers/userController.js

const asyncHandler = require('express-async-handler');
const sendToken = require('../utils/jwtToken');

const user = require('../models/user');

const axios = require('axios');
const dotenv = require("dotenv").config();


// Get all users => GET api/users
const getAllUser = asyncHandler(async (req, res) => {
    const users = await user.find();
    res.status(200).json(users);
});

//Get single users => api/user/:id
const getUserById = async (req, res) => {
    try {
      const { id } = req.params;
  
      const foundUser = await user.findById(id);
  
      if (!foundUser) {
        return res.status(404).json({ message: 'User not found' });
      }
  
      res.status(200).json(foundUser);
    } catch (error) {
      console.error(error);
      res.status(500).json({ message: 'Server Error' });
    }
  };


// Create new user => POST api/users/create
const createUser = asyncHandler(async (req, res) => {
    try {
        const { username, password, email, isGoogleAccount } = req.body;

        const newUser = await user.create({
            username,
            password,
            email,
            isGoogleAccount 
        });

        // Respond with the newly created user
        res.status(201).json(newUser);
    } catch (err) {
        // Handle validation errors
        if (err.name === 'ValidationError') {
            console.error(err);
            return res.status(400).json({ error: err.message });
        }

        console.error(err);
        res.status(500).json({ error: 'An error occurred while creating the user.' });
    }
});

// Delete user => api/users/delete/:id
const deleteUser = asyncHandler(async (req, res) => {
    try {
        const userId = req.params.id;

        const deleteUserId = await user.findById(userId);

        if(!deleteUserId) {
            return res.status(404).send('User ID not found!');
        }

        await user.findByIdAndDelete(userId);

        res.status(200).send({
            message: `Deleted ${userId} from database`
        });
    } catch(err) {
        console.log(err);
    }
});

// Update user => api/users/update/:id
const updateUser = asyncHandler(async (req, res) => {
    let users = await user.findById(req.params.id);

    if(!users) {
        return res.status(404).send('User not found!');
    }

    users = await user.findByIdAndUpdate(req.params.id, req.body, {
        new: true,
    })
    res.status(200).json(users)
});

// Login user => api/users/login
const loginUser = asyncHandler(async (req, res) => {
    try {
        const { email, password } = req.body;

        if(!email || !password) {
            return res.status(400).send('Please enter email & password');
        }

        const users = await user.findOne({ email }).select('+password');

        if(!users) {
            return res.status(400).send('Invalid Email');
        }

        const isPasswordMatched = await users.comparePassword(password);

        if(!isPasswordMatched) {
            return res.status(401).send('Invalid Password');
        }

        sendToken(users, 200, res);
    } catch(err){
        console.log(err);
    }
});

// Logout user => api/users/logout
const logoutUser = asyncHandler(async (req, res) => {
    res.cookie('token', null, {
        expires: new Date(Date.now()),
        httpOnly: true
    });

    res.status(200).json({
        success: true,
        message: 'Logged out'
    });
});

const googleAuth = asyncHandler(async (req, res) => {
    try {
        // get the code from frontend
        const code = req.headers.authorization;
        console.log('Authorization Code:', code);
        
        // Exchange the authorization code for an access token
        const response = await axios.post(
            'https://oauth2.googleapis.com/token',
            {
                code,
                client_id: process.env.CLIENT_ID,
                client_secret: process.env.CLIENT_SECRET,
                redirect_uri: 'postmessage',
                grant_type: 'authorization_code'
            }
        );
        const accessToken = response.data.access_token;
        console.log('Access Token:', accessToken);
        
        // Fetch user details using the access token
        const userResponse = await axios.get(
            'https://www.googleapis.com/oauth2/v3/userinfo',
            {
                headers: {
                    Authorization: `Bearer ${accessToken}`
                }
            }
        );
        const userDetails = userResponse.data;
        console.log('User Details:', userDetails);
        
        // Process user details and perform necessary actions

        const users = await user.findOne({ email: userDetails.email })

        if(!users){
            const newUser = await user.create({
                username: userDetails.name,
                password:"nothing",
                email: userDetails.email,
                isGoogleAccount: userDetails.email_verified
            });
        }
        
        sendToken(users, 200, res);
    } catch (error) {
        console.error('Error saving code:', error);
        res.status(500).json({ message: 'Failed to save code' });
    }
});

module.exports = { getAllUser, getUserById, createUser, deleteUser, updateUser, loginUser, logoutUser , googleAuth};