const net = require('net');
const path = require('path');
const fs = require('fs');
const os = require('os');

// Create a temporary directory for IPC socket
const tmpDir = os.tmpdir();
const sockPath = path.join(tmpDir, 'node-ipc-example.sock');

// Clean up any existing socket file
if (fs.existsSync(sockPath)) {
  console.log('Removing existing socket file');
  fs.unlinkSync(sockPath);
}

// Create an IPC server
const server = net.createServer((socket) => {
  console.log('IPC Server: Client connected');
  
  // Set encoding for the socket
  socket.setEncoding('utf8');
  
  // Handle data from client
  socket.on('data', (data) => {
    console.log(`IPC Server received: ${data.trim()}`);
    
    // Send a response
    const response = `Processed: ${data.trim().toUpperCase()}`;
    console.log(`IPC Server sending: ${response}`);
    socket.write(response);
  });
  
  // Handle client disconnection
  socket.on('end', () => {
    console.log('IPC Server: Client disconnected');
  });
  
  // Handle errors
  socket.on('error', (err) => {
    console.error('IPC Server socket error:', err.message);
  });
});

// Handle server errors
server.on('error', (err) => {
  console.error('IPC Server error:', err.message);
  
  // Try to clean up the socket file
  if (fs.existsSync(sockPath)) {
    try {
      fs.unlinkSync(sockPath);
    } catch (e) {
      console.error('Failed to clean up socket file:', e.message);
    }
  }
});

// Start the IPC server
server.listen(sockPath, () => {
  console.log(`IPC Server listening on ${sockPath}`);
  
  // Start a client to test the IPC connection
  startIPCClient();
});

// Function to start the IPC client
function startIPCClient() {
  console.log('Starting IPC client...');
  
  // Create a client connection to the IPC server
  const client = net.createConnection({ path: sockPath }, () => {
    console.log('IPC Client: Connected to server');
    
    // Send some test messages
    const messages = [
      'Hello, IPC Server!',
      'This is a test message',
      'Another message',
      'QUIT'
    ];
    
    let index = 0;
    
    // Function to send the next message
    const sendNext = () => {
      if (index < messages.length) {
        const msg = messages[index++];
        console.log(`IPC Client sending: ${msg}`);
        client.write(msg + '\n');
      } else {
        client.end();
      }
    };
    
    // Handle responses from server
    let buffer = '';
    client.on('data', (data) => {
      buffer += data.toString();
      
      // Split by newlines to handle multi-line responses
      const lines = buffer.split('\n');
      buffer = lines.pop(); // Keep the last incomplete line in the buffer
      
      // Process complete lines
      for (const line of lines) {
        if (line) { // Skip empty lines
          console.log(`IPC Client received: ${line}`);
          
          // If this was a response to QUIT, end the connection
          if (line.includes('QUIT')) {
            client.end();
            return;
          }
          
          // Send the next message after a short delay
          setTimeout(sendNext, 500);
        }
      }
    });
    
    // Start sending messages
    sendNext();
  });
  
  // Handle connection close
  client.on('close', () => {
    console.log('IPC Client: Connection closed');
    
    // Close the server after a short delay
    setTimeout(() => {
      server.close(() => {
        console.log('IPC Server closed');
        
        // Clean up the socket file
        if (fs.existsSync(sockPath)) {
          try {
            fs.unlinkSync(sockPath);
            console.log('Removed socket file');
          } catch (e) {
            console.error('Failed to remove socket file:', e.message);
          }
        }
      });
    }, 1000);
  });
  
  // Handle connection errors
  client.on('error', (err) => {
    console.error('IPC Client error:', err.message);
    
    // Try to close the server
    if (server.listening) {
      server.close();
    }
  });
}

// Handle process termination
process.on('SIGINT', () => {
  console.log('\nCaught interrupt signal');
  
  // Close the server
  if (server.listening) {
    server.close(() => {
      // Clean up the socket file
      if (fs.existsSync(sockPath)) {
        try {
          fs.unlinkSync(sockPath);
          console.log('Removed socket file');
        } catch (e) {
          console.error('Failed to remove socket file:', e.message);
        }
      }
      process.exit(0);
    });
  } else {
    process.exit(0);
  }
});