/*
 * StopWatch2.java
 * Model contains the data and the state for the stopwatch
 * Created on December 7, 2001, 8:29 AM
 *
 * @author  Stuart Hansen
 * @version
 */

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.beans.*;

import Views.*;

public class StopWatch2 extends JFrame {
    private long currentTime;   // the current time
    
    private Timer timer;        // the timer goes off every 1/10 seconds (or so)
    private State state;        // the state keeps track of whether the stopwatch is running
    private JButton startStop;  // the start stop button
    private JButton reset;      // reset the stopwatch to 0    
    
    /** the constructor */
    public StopWatch2() {
        super ("StopWatch");
        
        // Set up the startStop button
        startStop = new JButton("Start/Stop");
        startStop.addActionListener(new startStopController());
        
	// Set up the reset button       
        reset = new JButton("Reset");
        reset.addActionListener(new resetController());

        // Add the buttons to the container
        Container c = getContentPane();
        c.setLayout(new FlowLayout());
        c.add(startStop);
        c.add(reset);
       
        // setup the current time variables
        currentTime = 0;

        // Set up the timer
        timer = new Timer(67, new TimerHandler ());
        state = new Stopped();
        timer.setRepeats(true);
        timer.start();

	     // Set a few window properties and open the window
        setSize(300, 50); 
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);          
        setVisible(true);
    }
    
    // getters and setters for the time variables
    public long getCurrentTime () {
        return currentTime;
    }

    // When we set the time, we fire off an event
    public void setCurrentTime (long timeArg) {
        long temp = getCurrentTime();
        currentTime = timeArg;
        firePropertyChange("currentTime", new Long(temp), new Long(currentTime));
    }

    // addView sets up a new viewer for the stopWatch
    public void addView (SWView view) {
        addPropertyChangeListener(view);
	view.addPropertyChangeListener(new TimeRequestController());
    }        

    // TimeHandler updates handles the timer going off
    class TimerHandler implements ActionListener {
        public void actionPerformed (ActionEvent e) {
            state.updateTime();
        }
    }
    
    // State is the state of the data model
    private interface State {
	// Responds to the timer events
        public void updateTime();

	// Responds to startStop button
        public void startStopPushed();

	// Responds to the reset button
        public void resetPushed();
    }

    // Stopped and Started are states for the model
    // A stopped watch is not running
    private class Stopped implements State {

	// We disable reset while the watch is running
	// We re-enable it when the watch stops
        public Stopped () {
           reset.setEnabled(true);
        }

	// When the watch is stopped, we don't update the time
        public void updateTime () { }

	// The startStop button starts the watch
        public void startStopPushed() {
            state = new Started();
        }

	// The reset button sets the time to 0
        public void resetPushed() { 
            setCurrentTime(0);
        }
    }
    
    // A started watch is running
    private class Started implements State {

	// Reset is disabled while the watch is running
        public Started() {
            reset.setEnabled(false);
        }

	// We update the current time variable with each timer event
        public void updateTime () {
            setCurrentTime(getCurrentTime()+1);
        }

	// startStop stops the watch
        public void startStopPushed() {
            state = new Stopped();
        }

	// We do not reset the time while the watch is running
        public void resetPushed() { }
    }
    
    // startStopController sits between the button and the model
    public class startStopController extends AbstractAction {
        public void actionPerformed (ActionEvent e) {
            state.startStopPushed();
        }
    }

    // resetController sits between the button and the model
    public class resetController extends AbstractAction {
        public void actionPerformed (ActionEvent e) {
            state.resetPushed();
        }
    }

    // This class listens for requests for the current time
    public class TimeRequestController implements PropertyChangeListener {
        public void propertyChange (PropertyChangeEvent evt) {
            firePropertyChange("currentTime", null, new Long(currentTime));
	}
    }         

}