const express = require('express');
const http = require('http');
const socketIo = require('socket.io');
const cors = require('cors');
const session = require('express-session');
const app = express();
const server = http.createServer(app);
const io = socketIo(server, {
    cors: {
        origin: "http://localhost:5173",
        methods: ["GET", "POST"],
        credentials: true
    }
});

app.use(cors({
    origin: "http://localhost:5173",
    methods: ["GET", "POST"],
    credentials: true
}));
app.use(express.json());
app.use(session({
    secret: 'your-secret-key',
    resave: false,
    saveUninitialized: false,
    cookie: { secure: false }
}));

let users = {};
let admins = {};
let messages = [];

app.post('/register', (req, res) => {
    const { id, name } = req.body;
    if (!id || !name) {
        return res.status(400).json({ error: 'ID and Name are required' });
    }
    users[id] = { id, name };
    res.status(200).json(users);
});

app.get('/users', (req, res) => {
    res.status(200).json(users);
});

app.post('/registerAdmin', (req, res) => {
    const { name, password } = req.body;
    if (!name || !password) {
        return res.status(400).json({ error: 'Name and Password are required' });
    }
    if (admins[name]) {
        return res.status(400).json({ error: 'Admin already exists' });
    }
    admins[name] = { password };
    res.status(200).json({ message: 'Admin successfully registered' });
});

app.post('/loginAdmin', (req, res) => {
    const { name, password } = req.body;
    if (!name || !password) {
        return res.status(400).json({ error: 'Name and Password are required' });
    }
    if (!admins[name] || admins[name].password !== password) {
        return res.status(400).json({ error: 'Invalid credentials' });
    }
    req.session.user = { name };
    res.status(200).json({ message: 'Login successful' });
});

app.post('/logoutAdmin', (req, res) => {
    req.session.destroy(err => {
        if (err) {
            return res.status(500).json({ error: 'Logout failed' });
        }
        res.status(200).json({ message: 'Logout successful' });
    });
});

const checkAuth = (req, res, next) => {
    if (!req.session.user) {
        return res.status(401).json({ error: 'Not authenticated' });
    }
    next();
};

app.post('/sendMessage', checkAuth, (req, res) => {
    const { content, recipient } = req.body;
    if (!content || !recipient) {
        return res.status(400).json({ error: 'Content and Recipient are required' });
    }
    const message = { content, sender: req.session.user.name, recipient };
    messages.push(message);
    io.emit('receiveMessage', message);
    res.status(200).json(message);
});

app.post('/endConversation', checkAuth, (req, res) => {
    const { recipient } = req.body;
    if (!recipient) {
        return res.status(400).json({ error: 'Recipient is required' });
    }
    messages = messages.filter(msg => msg.recipient !== recipient);
    io.emit('receiveMessage', { type: 'conversationEnded', recipient });
    res.status(200).json({ message: 'Conversation ended' });
});

app.post('/deleteUser', checkAuth, (req, res) => {
    const { id } = req.body;
    if (!id) {
        return res.status(400).json({ error: 'User ID is required' });
    }
    delete users[id];
    messages = messages.filter(msg => msg.recipient !== id);
    io.emit('updateUsers', Object.values(users));
    io.emit('receiveMessage', { type: 'userDeleted', id });
    res.status(200).json({ message: 'User successfully deleted' });
});

io.on('connection', (socket) => {
    console.log('User connected');

    socket.on('sendMessage', (message) => {
        io.emit('receiveMessage', message);
    });

    socket.on('endConversation', (data) => {
        const { recipient } = data;
        messages = messages.filter(msg => msg.recipient !== recipient);
        io.emit('receiveMessage', { type: 'conversationEnded', recipient });
    });

    socket.on('disconnect', () => {
        console.log('User disconnected');
    });
});

server.listen(3001, () => {
    console.log('Server running on port 3001');
});