import java.net.*;
import java.io.*;

// Implement a simple MUSH client in one class, including a static main() that
// instantiates the class
public class MUSHClient {
  // The internet hostname of the MUSH to connect to
  private String hostname;

  // The port on the server where the MUSH is located
  private int port;

  // The IP address of the server; we look it up early on in the object's life
  private InetAddress ip_address;

  // A socket that will be connected to the remove host
  private Socket socket;

  // For buffered reading of data from the socket
  private BufferedReader socket_input;

  // For writing data to the socket
  private PrintWriter socket_output;

  // Remember whether we are connected or not
  private boolean connected;

  // This is how the client knows it is time to quit the main loop
  private boolean run_client;

  // A sample driver for the client, although it could easily be instantiated
  // from other code
  public static void main(String[] args) {
    String hostname;
    int port;
    BufferedReader in;
    MUSHClient client;

    client = null;
    in = new BufferedReader(new InputStreamReader(System.in));

    // First, read in the hostname and port to connect to
    try {
      System.out.print("Hostname: ");
      hostname = in.readLine();
      System.out.print("Port:     ");
      port = Integer.parseInt(in.readLine());
    } catch (Exception e) {
      System.out.println("Exception: " + e);
      return;
    }

    // Second, instantiate the client, connect it to the MUSH, and run the
    // main loop
    try {
      client = new MUSHClient(hostname, port);
      client.connect();
      client.run();
    } catch (Exception e) {
      System.out.println("Exception: " + e);
    } finally {
      // Clean up by disconnecting from the MUSH
      try {
        if (client != null && client.connected())
          client.shutdown();
      } catch (Exception e) {
        System.out.println("Exception: " + e);
      }
    }
  }

  // Constructor; takes a hostname and port to connect to and performs the
  // DNS lookup
  public MUSHClient(String hostname, int port) throws UnknownHostException {
    this.hostname = hostname;
    this.port = port;
    ip_address = InetAddress.getByName(hostname);
    connected = false;
  }

  // Return whether the client is currently in a connected state
  public boolean connected() {
    return connected;
  }

  // Connect to the MUSH by creating a socket connection and the appropriate
  // reader and writer objects, then setting the connected attribute
  public void connect() throws IOException {
    socket = new Socket(ip_address, port);
    socket_input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    socket_output = new PrintWriter(socket.getOutputStream(), true);
    connected = true;
  }

  // Handle a command from the user, which currently should be either /quit or
  // a line of text to pass on to the MUSH
  public void handle_command(String command) {
    if (command.equals("/quit")) {
      run_client = false;
      return;
    }

    socket_output.println(command);
  }

  // Run the main loop until the user types /quit
  public void run() throws IOException {
    BufferedReader console_input = new BufferedReader(new InputStreamReader(System.in));

    System.out.println("Type /quit to quit.");

    run_client = true;

    while (run_client) {
      if (console_input.ready())
        handle_command(console_input.readLine());

      while (socket_input.ready()) {
        String input_line = socket_input.readLine();
        System.out.println(input_line);
      }
    }
  }

  // Disconnect from the MUSH
  public void shutdown() throws IOException {
    socket.close();
    connected = false;
  }
}