server.js

import express from 'express';
import mongoose from 'mongoose';
import cors from 'cors';
import cookieParser from 'cookie-parser';
import dotenv from 'dotenv';
import { createServer } from 'http';
import { Server } from 'socket.io';
import userRoutes from './src/routes/userRoute.js';
import authRoutes from './src/routes/authRoutes.js';
import chatRoutes from './src/routes/chatRoutes.js';
import questionRoutes from './src/routes/questionRoutes.js';
import tagRoutes from './src/routes/tagRoutes.js';
import profileRoutes from './src/routes/profileRoutes.js';
import userProfileRoutes from './src/routes/userProfileRoutes.js';
import answerRoutes from './src/routes/answerRoutes.js';
import adminRoutes from './src/routes/adminRoutes.js';
import dashboardRoutes from './src/routes/dashboardRoutes.js';
import session from 'express-session';
import passport from 'passport';
import { Strategy as GoogleStrategy } from 'passport-google-oauth20';
import User from './src/models/User.js';
import socketHandler from './src/services/socketHandler.js';

dotenv.config();
const app = express();
const server = createServer(app);

// Socket.IO setup
const io = new Server(server, {
  cors: {
    origin: "http://localhost:5173",
    methods: ["GET", "POST"],
    credentials: true
  },
  path: "/socket.io"
});

// Initialize socket handler
socketHandler(io);

// Middleware
app.use(cors({
  origin: 'http://localhost:5173',
  credentials: true
}));
app.use(express.json());
app.use(cookieParser());
app.use(session({
  secret: process.env.SESSION_SECRET || 'your-session-secret',
  resave: false,
  saveUninitialized: false,
  cookie: { secure: false }
}));
app.use(passport.initialize());
app.use(passport.session());

// Passport Google OAuth setup
passport.use(new GoogleStrategy({
  clientID: process.env.GOOGLE_CLIENT_ID,
  clientSecret: process.env.GOOGLE_CLIENT_SECRET,
  callbackURL: 'http://localhost:5000/api/auth/google/callback',
}, async (accessToken, refreshToken, profile, done) => {
  try {
    let user = await User.findOne({ email: profile.emails[0].value });
    if (!user) {
      user = await User.create({
        fullName: profile.displayName,
        email: profile.emails[0].value,
        password: 'google-oauth',
        avatar: profile.photos[0]?.value,
        isVerified: true,
      });
    }
    return done(null, user);
  } catch (err) {
    return done(err, null);
  }
}));

passport.serializeUser((user, done) => {
  done(null, user.id);
});
passport.deserializeUser(async (id, done) => {
  try {
    const user = await User.findById(id);
    done(null, user);
  } catch (err) {
    done(err, null);
  }
});

// Database connection
mongoose.connect(process.env.MONGODB_URI)
  .then(() => console.log('Connected to MongoDB'))
  .catch((err) => console.error('MongoDB connection error:', err));

// Routes
app.use('/api/users', userRoutes);
app.use('/api/auth', authRoutes);
app.use('/api/chats', chatRoutes);
app.use('/api/questions', questionRoutes);
app.use('/api/question', questionRoutes); // Alias for frontend compatibility
app.use('/api/tags', tagRoutes);
app.use('/api/profile', profileRoutes);
app.use('/api/profile', userProfileRoutes);
app.use('/api/answer', answerRoutes);
app.use('/api/admin', adminRoutes);
app.use('/api/dashboard', dashboardRoutes);

// Error handling middleware
app.use((err, req, res, next) => {
  console.error('Error:', err);
  res.status(err.status || 500).json({
    success: false,
    message: err.message || 'Internal server error',
    ...(process.env.NODE_ENV === 'development' && { stack: err.stack })
  });
});

const PORT = process.env.PORT || 5000;
server.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
  console.log(`Socket.IO server is ready`);
});