// Midi.java
// Based on BasicGUI.java, this shows how to load midi files.
// David Kosbie, 15-111/AB, Spring 2007

/*
Standard disclaimer:  As usual with sample code designed (often in
class!) to demonstrate specific issues, the style may not be perfect
(it is especially lacking comments and some top-down design),
and there may even be a bug or two lurking in the code!

This sample demonstrates the use of a very simple MidiPlayer class.
This class only has a few static methods, allowing you to play or
stop a midi file (and you can play it once or looping).  For more
advanced use, you can get the Sequencer object.  See the Java API
for details.

//////////////////////////////////////////////
// MidiPlayer API (all statics)
//////////////////////////////////////////////

class MidiPlayer {
	public static void play(String filename);
	public static void play(String filename, boolean loop);
	public static Sequencer getSequencer();  // for advanced use!
	public static void stop();
}

*/

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

// Additional imports for MidiPlayer:
import java.io.*;
import javax.sound.midi.*;

public class Midi extends IntroCsApplication {

  public static void main(String[] args) { new Midi(); }
  
  JLabel nowPlaying;

  public void init() {
	add(nowPlaying = newCenteredLabel("No midi file playing yet!"));
  	addButtons("Play Next", "Play Next (Looping)", "Stop");
  }
  
  public void playNextMidiFile(boolean loop) {
  	String midiFilename = getNextMidiFilename();
  	if (midiFilename == null)
  		nowPlaying.setText("No midi files found!!!");
  	else {
  		nowPlaying.setText("Now playing: " + midiFilename.toString() + "  ");
  		MidiPlayer.play(midiFilename,loop);
  	}
  }
  
  public void stopPlayingMidi() {
  	MidiPlayer.stop();
  	nowPlaying.setText("Midi player stopped!");
  }

  public void onButtonPressed(String label) {
  	if (label.equals("Play Next")) playNextMidiFile(false);
  	else if (label.equals("Play Next (Looping)")) playNextMidiFile(true);
  	else if (label.equals("Stop")) stopPlayingMidi();
  }
  
  // find next ".mid" file in this directory
  // or return null if none are found
  public String getNextMidiFilename() {
  	java.io.File directory = new java.io.File(".");    
    String[] files = directory.list();
    for (int i=0; i<files.length; i++) {
    	String filename = files[(i+nextMidiIndex)%files.length];
    	if (filename.endsWith(".mid")) {
    		nextMidiIndex += (i + 1);
    		return filename;
    	}
    }
    return null;
  }
  
  private int nextMidiIndex = 0;
  
  public static JLabel newCenteredLabel(String text) {
  	JLabel label = new JLabel(text);
	label.setAlignmentX(Component.CENTER_ALIGNMENT);
	return label;
  }
}

  ////////////////////////////////////////////////////////////
  ////////////////////////////////////////////////////////////
  // You are not (yet) responsible for the code below here!
  //
  // MidiPlayer
  //
  // Include this class if you want to play midi files,
  // And include these imports:
  //
  // import java.io.*;
  // import javax.sound.midi.*;
  //
  ////////////////////////////////////////////////////////////
  ////////////////////////////////////////////////////////////  

class MidiPlayer {
	public static void play(String filename) { play(filename,false); }
	
	public static void play(String filename, boolean loop) {
		try {
			stop();
			sequencer = MidiSystem.getSequencer();
			File midiFile = new File(filename);
			sequencer.setSequence(MidiSystem.getSequence(midiFile));
			if (loop)
				sequencer.setLoopCount(Sequencer.LOOP_CONTINUOUSLY);
			sequencer.open();
	        sequencer.start();
	     } catch (Exception e) {
	     	System.err.println("MidiPlayer: " + e);
	     	sequencer = null;
	     }
	}
	
	public static Sequencer getSequencer() { return sequencer; }
	
	public static void stop() {
		try {
			if ((sequencer == null) || (!sequencer.isRunning())) return;
			sequencer.stop();
			sequencer.close();
		}
		catch (Exception e) {
	     	System.err.println("MidiPlayer: " + e);
		}
		sequencer = null;
	}

	private static Sequencer sequencer = null;	
}

  ////////////////////////////////////////////////////////////
  ////////////////////////////////////////////////////////////
  // You are not (yet) responsible for the code below here!
  ////////////////////////////////////////////////////////////
  ////////////////////////////////////////////////////////////  

class IntroCsComponent extends JComponent {

  public IntroCsComponent() {
    this.addEventListeners();
    this.setPreferredSize(new Dimension(400,400));
  } 

  // override these methods to respond to events
  public void onTimer() { }
  public void onMousePressed(int x, int y) { }
  public void onMouseDragged(int x, int y) { }
  public void onMouseReleased(int x, int y) { }
  public void onKeyPressed(KeyEvent e, int keyCode, char keyChar) { }
  public void onResized() { }

  public void beep() {
	Toolkit.getDefaultToolkit().beep();
  }

  public void startTimer(final int timerDelay) { 
    // use invokeLater to allow window to become visible before starting
    // to be initialized in subclasses before calling init() method
 	javax.swing.SwingUtilities.invokeLater(new Runnable() {
		public void run() {
		    new javax.swing.Timer(timerDelay, new ActionListener() {
		      public void actionPerformed(ActionEvent evt) {
		        onTimer();
		        repaint();
		      }
		    }).start();
		}
 	});
  }  
   
  protected void addEventListeners() {
    // add actions in response to mouse events
    addMouseListener(new MouseAdapter() {
      public void mousePressed(MouseEvent e) {
        onMousePressed(e.getX(),e.getY());
        repaint();
      }
      public void mouseReleased(MouseEvent e) {
        onMouseReleased(e.getX(),e.getY());
        repaint();
      }
    });
    
    // and for mouse motion events
    addMouseMotionListener(new MouseMotionAdapter() {
      public void mouseDragged(MouseEvent e) {
        onMouseDragged(e.getX(),e.getY());
        repaint();
      }
    });
    
    // and for keyboard events
    addKeyListener(new KeyAdapter() {
      public void keyPressed(KeyEvent e) {
        onKeyPressed(e,e.getKeyCode(),e.getKeyChar());
        repaint();
      }
    });

    // and for component events
    addComponentListener(new ComponentAdapter() {
      public void componentResized(ComponentEvent e) {
        onResized();
        repaint();
      }
    });
  }
}

class IntroCsApplication extends JFrame {

  public void init() {
  	// override this method to add your buttons, objects, etc
  }

  public void onTimer() { }  

  // This method lives outside the anonymous inner class Runnable
  // so that getClass() returns this class (in fact, the overridden subclass)  
  protected String makeTitle() {
  	return this.getClass().getName();
  }

  public IntroCsApplication() {
  	super();
    Container cp = this.getContentPane();
  	cp.setBackground(Color.white);
	cp.setLayout(new BoxLayout(cp,BoxLayout.Y_AXIS));
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // use invokeLater to allow instance variables (like buttonLabels[])
    // to be initialized in subclasses before calling init() method
 	javax.swing.SwingUtilities.invokeLater(new Runnable() {
		public void run() {
			init();  // override this method!
			pack();
			if (focusComponent != null)
	  			// send key events to this component!
  				focusComponent.requestFocusInWindow();
		  	setTitle(makeTitle());
			setVisible(true);
		}
 	});
  }
  
  private IntroCsComponent focusComponent = null;
  
  public Component add(Component c) {
  	Component result = super.add(c);
  	if (c instanceof IntroCsComponent) {
  		// the first one added gets the keyboard by default
  		if (focusComponent == null) {
  			focusComponent = (IntroCsComponent) c;
  			// send key events to this component!
  			focusComponent.requestFocusInWindow();
  		}
  	}
  	return result;
  }

  public void onButtonPressed(String label) {
  	System.out.printf("onButtonPressed(%s)\n",label);
  }

  public void addButtons(String... buttonLabels) {
  	JPanel buttons = new JPanel();
  	buttons.setLayout(new BoxLayout(buttons,BoxLayout.X_AXIS));
  	for (int i=0; i<buttonLabels.length; i++) {
  		JButton button = new JButton(buttonLabels[i]);
  		button.setFocusable(false);
  		button.addActionListener(new ActionListener() {
  			public void actionPerformed(ActionEvent e) {
  				onButtonPressed(((JButton)e.getSource()).getText());
  				repaint();
  			}
  		});
  		buttons.add(button);
  	}
  	this.getContentPane().add(buttons);
  }
  
  public void beep() {
	Toolkit.getDefaultToolkit().beep();
  }

  public void startTimer(final int timerDelay) { 
    // use invokeLater to allow window to become visible before starting
    // to be initialized in subclasses before calling init() method
 	javax.swing.SwingUtilities.invokeLater(new Runnable() {
		public void run() {
		    new javax.swing.Timer(timerDelay, new ActionListener() {
		      public void actionPerformed(ActionEvent evt) {
		        onTimer();
		      }
		    }).start();
		}
 	});
 }  
}