client.js

const grpc = require('@grpc/grpc-js');
const protoLoader = require('@grpc/proto-loader');
const path = require('path');
const readline = require('readline'); // For user input

// Load the protobuf definition
const PROTO_PATH = path.join(__dirname, 'chat.proto');
const packageDefinition = protoLoader.loadSync(PROTO_PATH, {
  keepCase: true,
  longs: String,
  enums: String,
  defaults: true,
  oneofs: true,
});
const chat_proto = grpc.loadPackageDefinition(packageDefinition).chat;

// Create a gRPC client
const client = new chat_proto.ChatService('localhost:50051', grpc.credentials.createInsecure());

// Set up readline for user input
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

let userName = '';

// Function to start the chat
function startChat() {
  console.log(`Welcome to the gRPC Chat! Your name: ${userName}`);
  console.log('Type your message and press Enter. Type "exit" to quit.');

  const call = client.Chat(); // Initiate the bidirectional stream

  // Handle incoming messages from the server
  call.on('data', (message) => {
    const date = new Date(Number(message.timestamp));
    console.log(`\n[${message.sender} - ${date.toLocaleTimeString()}]: ${message.message}`);
    rl.prompt(true); // Re-prompt after receiving a message
  });

  call.on('end', () => {
    console.log('Server stream ended.');
    rl.close();
    process.exit();
  });

  call.on('error', (err) => {
    console.error('Stream error:', err.message);
    rl.close();
    process.exit(1);
  });

  call.on('status', (status) => {
    console.log('Stream status:', status);
  });

  // Handle outgoing messages from user input
  rl.on('line', (line) => {
    if (line.toLowerCase() === 'exit') {
      call.end(); // End the client's side of the stream
      rl.close();
      return;
    }
    if (line.trim() !== '') {
      const chatMessage = {
        sender: userName,
        message: line.trim(),
      };
      call.write(chatMessage);
    }
    rl.prompt(true); // Prompt again for the next message
  });

  rl.prompt(true);
}

// Ask for the user's name before starting the chat
rl.question('Please enter your name: ', (name) => {
  userName = name.trim();
  if (userName === '') {
    console.log('Name cannot be empty. Exiting.');
    rl.close();
    process.exit(1);
  } else {
    startChat();
  }
});

process.on('SIGINT', () => {
    console.log('\nExiting chat...');
    rl.close();
    process.exit();
});