const express = require('express');
const app = express();
const http = require('http').createServer(app);
const io = require('socket.io')(http);
const path = require('path');
const fs = require('fs');

const messagesFile = path.join(__dirname, 'messages.json');
let chatHistory = [];

if (fs.existsSync(messagesFile)) {
    try {
        const data = fs.readFileSync(messagesFile);
        chatHistory = JSON.parse(data);
    } catch (e) {
        console.error("Erro ao ler histórico", e);
    }
}

app.use(express.static(path.join(__dirname, 'public')));

io.on('connection', (socket) => {
    socket.emit('chat history', chatHistory);

    // Gestão do indicador de digitação
    socket.on('typing', (data) => {
        socket.broadcast.emit('typing', data);
    });

    socket.on('chat message', (data) => {
        chatHistory.push(data);
        if (chatHistory.length > 500) chatHistory.shift(); 
        fs.writeFileSync(messagesFile, JSON.stringify(chatHistory));
        io.emit('chat message', data);
    });
});

const PORT = 3000;
http.listen(PORT, () => {
    console.log(`Servidor de Chat a correr na porta ${PORT}`);
});