Real-Time Notifications and Presence Tracking with Socket.io

import { createServer } from 'http';
import { Server } from 'socket.io';

const httpServer = createServer(app);

export const io = new Server(httpServer, {
  cors: {
    origin: [
      'http://localhost:5173',
      'http://localhost:5174',
      'http://localhost:5175',
      'https://eco-it.netlify.app'
    ],
    methods: ['GET', 'POST']
  }
});

io.use((socket, next) => {
  const token =
    socket.handshake.auth?.token ||
    socket.handshake.headers?.authorization?.split(' ')[1];

  if (!token) return next(new Error('Authentication error: Token required'));

  try {
    const decoded = jwt.verify(token, process.env.JWT_SECRET);
    socket.usuario = decoded;
    next();
  } catch {
    next(new Error('Authentication error: Invalid token'));
  }
});

import { io } from 'socket.io-client';

const BACKEND_URL = import.meta.env.VITE_BACKEND_URL || 'http://localhost:3000';

const socket = io(BACKEND_URL, {
  auth: {
    token: localStorage.getItem('token'), // JWT stored after login
  },
});

// Announce presence once the connection is established
socket.on('connect', () => {
  socket.emit('usuario:conectado');
});

// Update online user count in the UI
socket.on('usuarios:online', (count) => {
  console.log(`Usuarios en línea: ${count}`);
});

// Track individual user status changes
socket.on('usuario:estado', ({ userId, isOnline }) => {
  console.log(`User ${userId} is now ${isOnline ? 'online' : 'offline'}`);
});

// Admin-only: listen for content moderation alerts
socket.on('admin:alerta_lenguaje', (notification) => {
  showAdminAlert(`⚠️ Lenguaje inapropiado de ${notification.nombre}`);
});

socket.on('admin:alerta_obscena', (notification) => {
  showAdminAlert(`🚫 Imagen obscena de ${notification.nombre} — usuario baneado 3 días`);
});

socket.on('admin:usuario_baneado', (notification) => {
  showAdminAlert(`🔒 ${notification.nombre} ha sido baneado por ${notification.dias} día(s)`);
});