import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.TextArea.*;
import javax.swing.*;
import javax.swing.text.*;

/**
 * RunCmdsGUI is a Java application that takes any number of commands
 * defined in the String[] array cmds.
 * Please note I had to use the java.awt TextArea instead of the
 * Swing JTextArea, because the JTextArea had problems updating
 * the textarea real-time.  It is pretty cool, because it displays
 * both the stdout and stderr where they would be on the command-line.
 *
 * Run1 button executes commands specified by the commands in cmds
 *  under the Run1 section of actionPerformed
 * Run2 button executes commands specified by the commands in cmds
 *  under the Run2 section of actionPerformed
 *
 * Also please note, this code is probably not very 'correct'.
 * but it does work.
 *
 * @author Nick 
 * (see http://illx.org for more details)
 */
public class RunCmdsGUI extends JFrame implements ActionListener {
    //compiled output
    TextArea co;
    PrintStream ps;
    protected boolean done = false;
       
    public RunCmdsGUI() throws IOException {
        //new jpanel
        JPanel p;	
        
	//new container cp	
        Container cp = getContentPane();	
        cp.add(BorderLayout.NORTH, p = new JPanel());
        
        JButton b;
	p.add(b = new JButton("Run1"));
	b.addActionListener(this);

        JButton de;
	p.add(de = new JButton("Run2"));
	de.addActionListener(this);

        JButton close;
	p.add(close = new JButton("Close"));
	close.addActionListener(this);
        
	co = new TextArea(30, 60);
        co.setEditable(false);
        JScrollPane jsp = new JScrollPane(co);
	cp.add(BorderLayout.CENTER, new JScrollPane(co));

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	pack();			// end of GUI portion
    }

    public void actionPerformed(ActionEvent ev) {
        String b = ev.getActionCommand();
        
        co.setText(""); //flush the jtextarea
	String[] cmds = new String[3];

        if(b.equals("Run1")) {
            cmds[0] = "date";
            cmds[1] = "sleep 3";
            cmds[2] = "date";
        }
        else if(b.endsWith("Run2")) {
            cmds[0] = "date +%r";
            cmds[1] = "w";
        }
	else if(b.equals("Close")) {
	    System.exit(0);
	}
        else {
            co.append("this should not happen\n");
        }
        
	String cmdo = null;
	for(int i=0;i<cmds.length;i++) {
	    if(cmds[i] == null) 
		continue;

	    try { runCmd(cmds[i]); }
	    catch(IOException e) { System.err.println("IOException e"+e.getMessage()); }

	    while(done) {
		//just sit here and wait for the command to finish executing
		//this really screwed things up when it wasn't here
	    }
	}
    }
        
    public synchronized void runCmd(String acmd) throws IOException {
	final Process cmd = Runtime.getRuntime().exec(acmd);

	co.append("EXECUTING: '"+acmd+"'\n");
	Thread t1 = new Thread(new Runnable() {
		public void run() {
		    try { loadStream(cmd.getInputStream()); }
		    catch(IOException e) { System.err.println("IOException e"+e.getMessage()); }
		}
	    });
	Thread t2 = new Thread(new Runnable() {
		public void run() {
		    try { loadStream(cmd.getErrorStream()); }
		    catch(IOException e) { System.err.println("IOException e"+e.getMessage()); }
		}
	    });
	t1.start();
	t2.start();
    }

    public void loadStream(InputStream myin) throws IOException {
	done = true;
	int ptr = 0;
	StringBuffer buffer = new StringBuffer();
	InputStream in = new BufferedInputStream(myin, 1);

	while( (ptr = in.read()) != -1 ) {
	    String s = (char)ptr+"";
	    if(s.equals("\n")) {
		co.append(buffer.toString()+"\n");
		buffer.delete(0, buffer.length());
	    }
	    else {
		buffer.append((char)ptr);
	    }
	}
	done = false;
    }

    public static void process(String cmd, PrintStream pw) {
        try {
            // Redirect all output to the printstream
            System.setOut(pw);
            System.setErr(pw);
            System.out.println(cmd);
        }
        catch(Exception e) {
            pw.println(e);
        }
    }
    
    public static void main(String[] args) {
        try {
            new RunCmdsGUI().setVisible(true);
        }
        catch(IOException e) {
            System.out.println("IOException e:"+e.getMessage());
        }
    }
}