/* -*-mode:java; c-basic-offset:2; -*- */

import javax.microedition.midlet.*;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import java.io.*;
import com.jcraft.jsch.*;
import com.jcraft.jhttptunnel.*;

public class RemoteExecOverHttpTunnelMIDlet extends MIDlet implements Runnable, CommandListener {

  private static Display display;
  private Form f;
  private StringItem si;
  private TextField tf;
  private TextField pf;
  private TextField cf;
  private Command exitCommand=new Command("Exit", Command.EXIT, 0);
  private Command execCommand=new Command("Exec", Command.ITEM, 1);
  private Command cancelCommand=new Command("Cancel", Command.SCREEN, 0);
  private Command okCommand=new Command("Ok", Command.SCREEN, 1);
  private TextBox resultBox=new TextBox("Result", "", 1024, 0);
  private TextBox tb=new TextBox("Prompt", "", 64, 0);
  
  private Displayable nextScreen=null;

  private String host=null;
  private String user=null;
  private String command=null;

  private boolean isPaused;

  private final String UH="";
  private final String PASSWD="";
  private final String COMMAND="/bin/date";

  public RemoteExecOverHttpTunnelMIDlet() {
    display=Display.getDisplay(this);
    f=new Form("Remote Execution on SSH2 over HttpTunnel");
    si=new StringItem("Status", "No connection");
    tf=new TextField("user@hostname", UH, 30, TextField.ANY);
    pf=new TextField("Password", PASSWD, 8, TextField.PASSWORD);
    cf=new TextField("Command", COMMAND, 30, TextField.ANY);
    f.append(si);
    f.append(tf);
    f.append(pf);
    f.append(cf);
    f.append("Confirm that 'hts -F 127.0.0.1:22' is running on the remote host.");
    f.addCommand(exitCommand);
    f.addCommand(execCommand);
    f.setCommandListener(this);
    display.setCurrent(f);
  }

  public void start() {
    Thread t=new Thread(this);
    t.start();
  }

  public void run() {
    try{
      if(host!=null && user!=null){
	connect();
      }
      if(session==null){
	si.setText("No connection");
      }
    } 
    catch (Exception e) {
      //e.printStackTrace();
    }
  }

  public boolean isPaused(){ return isPaused; }
  public void startApp(){ isPaused=false; }
  public void pauseApp(){ isPaused=true; }

  public void destroyApp(boolean unconditional) {
    stop();
  }
  public void stop() {
    try {
      if(session!=null){
	session.disconnect();
	session=null;
      }
    }
    catch (Exception e) {}
    thread=null;
  }

  private Thread thread=null;
  public void commandAction(Command c, Displayable s) {
    if(c==okCommand && 
       display.getCurrent()==resultBox){
      if(nextScreen==f){
        f.addCommand(execCommand);
      }
      display.setCurrent(nextScreen);
      return;
    }
    if(c==okCommand || c==cancelCommand){
      if(c==cancelCommand){
        f.addCommand(execCommand);
      }
      display.setCurrent(f); 
    }
    if(c==execCommand && !isPaused()) {
      if(thread!=null && thread.isAlive()){
	return;
      }
      String _host=tf.getString();
      String _user=_host.substring(0, _host.indexOf('@'));
      _host=_host.substring(_host.indexOf('@')+1);
      if(_host==null || _host.length()==0 ||
	 _user==null || _user.length()==0){
	return;
      }
      host=_host;
      user=_user;
      thread=new Thread(this);
      thread.start();
      f.removeCommand(execCommand);
    }

    if((c==Alert.DISMISS_COMMAND) || (c==exitCommand)){
      stop();
      notifyDestroyed();
      destroyApp(true);
    }
  }

  public class MyUserInfo implements UserInfo, CommandListener{
    Alert prompt=new Alert("Prompt", "", null, AlertType.WARNING);
    boolean result=false;
    String passwd="";
    MyUserInfo(String passwd){
      this.passwd=passwd;
      prompt.setTimeout(Alert.FOREVER);
      prompt.setCommandListener(this);
    }
    public String getPassword(){ return passwd; }
    public boolean promptYesNo(String str){ 
      prompt.setString(str);
      prompt.addCommand(okCommand);
      prompt.addCommand(cancelCommand);
      Displayable current=display.getCurrent();
      display.setCurrent(prompt, current); 
      while(true){
        try{Thread.sleep(500);}
        catch(Exception e){}
        if(prompt!=display.getCurrent()){
          break;
        }
      }
      prompt.removeCommand(okCommand);
      prompt.removeCommand(cancelCommand);
      return result;
    }

    String passphrase="";
    public String getPassphrase(){ return passphrase; }
    public boolean promptPassphrase(String message){ return true; }
    public boolean promptPassword(String message){  return true; }
    public void showMessage(String message){
      prompt.setString(message);
      Displayable current=display.getCurrent();
      display.setCurrent(prompt, current);
      while(true){
        try{Thread.sleep(500);}
        catch(Exception e){}
        if(prompt!=display.getCurrent()){
          break;
        }
      }
    }
    public void commandAction(Command c, Displayable s) {
      if(c==okCommand){ result=true; }
      if(c==cancelCommand){ result=false; }
      display.setCurrent(f);
    }
  }

  private void connect(){
    si.setText("Connecting to "+user+"@"+host+"...");
    nextScreen=display.getCurrent();
    try{
      Session session=null;
      try{
	session=getSession(user, host);
      }
      catch(JSchException ee){
	//System.out.println(ee);
	si.setText("No connection");
	return;
      } 

      si.setText("Connected to "+user+"@"+host);

      resultBox.delete(0, resultBox.size());
      resultBox.setTitle(last_uh+": "+cf.getString());
      resultBox.addCommand(okCommand);
      resultBox.setCommandListener(this);
      display.setCurrent(resultBox);

      Channel channel=session.openChannel("exec");
      ((ChannelExec)channel).setCommand(cf.getString());
      InputStream in=channel.getInputStream();
      OutputStream out=channel.getOutputStream();
      channel.connect();

      int c;
      while(true){
	if(thread==null){ break; }
	c=in.read();
	if(c==-1)break; 
	if(c==0x0a){
	  //System.out.println(""); 
	  resultBox.insert("\n", resultBox.size());
	}
	else{
	  //System.out.print(new Character((char)c));
	  resultBox.insert(new Character((char)c).toString(),
			   resultBox.size());
	}
      }
      channel.disconnect();
    }
    catch(Exception e){
      //System.err.println(e);
    }
  }

  private JSch jsch=null;
  private Session session=null;
  private String last_uh="";
  private Session getSession(String user, String host) throws JSchException{

    if(jsch==null){
      jsch=new JSch();
      //ByteArrayInputStream bis=
      //  new ByteArrayInputStream(known_hosts.getBytes());
      //jsch.setKnownHosts(bis);
      //jsch.addIdentity(new IdentityMem(id_rsa, id_rsa_pub, jsch));
      //jsch.addIdentity(new IdentityMem(id_dsa, id_dsa_pub, jsch));
    }

    String foo=user+"@"+host;
    if(last_uh.equals(foo) && session!=null){
      return session;
    }
    if(session!=null){
      try{session.disconnect();}catch(Exception e){}
      session=null;
    }
    Session _session=jsch.getSession(user, host, 8888);
    _session.setUserInfo(new MyUserInfo(pf.getString()));
    _session.setSocketFactory(new SocketFactory() {
	InputStream in=null;
	OutputStream out=null;
	JHttpTunnelClient jhtc=null;
	public Object createSocket(String host, int port) throws IOException {
          //System.out.println("create: "+host+", "+port);
	  jhtc=new JHttpTunnelClient(host, port);
	  jhtc.setInBound(new InBoundConnector());
	  jhtc.setOutBound(new OutBoundConnector());
	  //jhtc.setProxy(proxy_host, proxy_port);                            
	  jhtc.connect();
	  return null;
	}
	public InputStream getInputStream(Object socket) throws IOException {
	  if(in==null)
	    in=jhtc.getInputStream();
	  return in;
	}
	public OutputStream getOutputStream(Object socket) throws IOException {
	  if(out==null)
	    out=jhtc.getOutputStream();
	  return out;
	}
      });

    _session.connect();
    last_uh=foo;
    session=_session;
    return session;
  }
}