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

public class QuadrilateralApplet extends JApplet implements ActionListener {
                            
    JLabel aLabel, bLabel, cLabel, dLabel, hLabel;
    JTextField aField, bField, cField, dField, hField;
    JButton zoomInButton, zoomOutButton;
    //JRadioButton hypoRadioButton, epiRadioButton, traceRadioButton;
    //ButtonGroup graphButtonGroup;
    
  //    JButton aUpButton, aDownButton, bUpButton, bDownButton, zoomInButton, zoomOutButton;
    //JSlider rSlider, dSlider;
    final static int westpanelwidth=150;
    final static int northpanelheight=50;
    
    double xLo=0, xHi=1, yLo=0, yHi=1;
    double a, b, c, d, h;
    //int graphChoice;   //hypo or epi
    //boolean trace=false;
    //double [] X, Y;
    
    public void init() {  

	
	Container container = getContentPane();  
	container.setLayout(null);   //** no Layout Manager	
	
	JPanel westPanel = new JPanel();
	westPanel.setLayout( new GridLayout(5,2) ); 
	westPanel.setBackground(Color.LIGHT_GRAY);
	westPanel.setBounds(0,0, westpanelwidth,100);
	//westPanel.setLayout(null); 
	container.add(westPanel);

        /*	
	JPanel coeffsPanel = new JPanel();
	coeffsPanel.setLayout(new FlowLayout());
	westPanel.add(coeffsPanel);
	*/
	/*
	JPanel plotXPanel = new JPanel();
	plotXPanel.setLayout(new FlowLayout());
	westPanel.add(plotXPanel);
	JPanel plotYPanel = new JPanel();
	plotYPanel.setLayout(new FlowLayout());
	westPanel.add(plotYPanel);
	JPanel plotTickPanel = new JPanel();
	plotTickPanel.setLayout(new FlowLayout());
	westPanel.add(plotTickPanel);
        */

	JPanel zoomPanel = new JPanel();
	zoomPanel.setBackground(Color.BLACK);
	//zoomPanel.setBounds(0,getHeight()-200, westpanelwidth,40);
	zoomPanel.setBounds(getWidth()-200,0, 200,40);
	container.add(zoomPanel);

/*	JPanel radioPanel = new JPanel();
	//radioPanel.setBackground(Color.BLACK);
	radioPanel.setBounds(200,0, 200,40);
	container.add(radioPanel);
*/

	aLabel = new JLabel( "a" );
	westPanel.add( aLabel );
	aField = new JTextField("1",3 );
	aField.setHorizontalAlignment(JTextField.RIGHT);
	aField.addActionListener( this );
	westPanel.add( aField );

	bLabel = new JLabel( "b" );
	westPanel.add( bLabel );
	bField = new JTextField("1",3 );
	bField.setHorizontalAlignment(JTextField.RIGHT);
	bField.addActionListener( this );
	westPanel.add( bField );

	cLabel = new JLabel( "c" );
	westPanel.add( cLabel );
	cField = new JTextField("1",3 );
	cField.setHorizontalAlignment(JTextField.RIGHT);
	cField.addActionListener( this );
	westPanel.add( cField );

	dLabel = new JLabel( "d" );
	westPanel.add( dLabel );
	dField = new JTextField("1",3 );
	dField.setHorizontalAlignment(JTextField.RIGHT);
	dField.addActionListener( this );
	westPanel.add( dField );

	hLabel = new JLabel( "h" );
	westPanel.add( hLabel );
	hField = new JTextField("1",3 );
	hField.setHorizontalAlignment(JTextField.RIGHT);
	hField.addActionListener( this );
	westPanel.add( hField );

/*	rSlider = new JSlider( SwingConstants.VERTICAL, 0, 100, 20 );
	rSlider.setMajorTickSpacing( 10 );
	//horizSlider.setMinorTickSpacing( 1 );
	rSlider.setPaintTicks( true );
	//horizSlider.setPaintLabels( true );
	rSlider.setBounds(0,100, 40,210);
	container.add(rSlider);
    	rSlider.addChangeListener(
	        new ChangeListener() {
		    public void stateChanged( ChangeEvent e ) {
			rField.setText(""+(rSlider.getValue()/100.0));
			rField.postActionEvent();  
		    }
		}
	);
*/
	//coeffsPanel.add( aField );
/*	aUpButton = new JButton( "\u2191" );
	aUpButton.setBounds(0,180,50,20);
	container.add( aUpButton );
	aUpButton.addActionListener( this );
	
	aDownButton = new JButton( "\u2193" );
	aDownButton.setBounds(0,200,50,20);
	container.add( aDownButton );
	aDownButton.addActionListener( this );
*/	
/*	hypoRadioButton = new JRadioButton( "Hypotrochoid" );
	hypoRadioButton.setSelected(true);
	radioPanel.add( hypoRadioButton );
	hypoRadioButton.addItemListener( this ); 
	graphChoice = 1;

	epiRadioButton = new JRadioButton( "Epitrochoid" );
	radioPanel.add( epiRadioButton );
	epiRadioButton.addItemListener( this ); 
	
	graphButtonGroup = new ButtonGroup();
	graphButtonGroup.add(hypoRadioButton);
	graphButtonGroup.add(epiRadioButton);


	traceRadioButton = new JRadioButton( "Trace" );
	traceRadioButton.setBounds(500,10,60,20);
	container.add( traceRadioButton );
	traceRadioButton.addItemListener( this ); 
*/
	//coeffsPanel.add( bField );
/*	bUpButton = new JButton( "\u2191" );
	bUpButton.setBounds(260,5,50,20);
	container.add( bUpButton );
	bUpButton.addActionListener( this );
	
	bDownButton = new JButton( "\u2193" );
	bDownButton.setBounds(260,25,50,20);
	container.add( bDownButton );
	bDownButton.addActionListener( this );
*/	
        /*
	xLowLabel = new JLabel( "X low" );
	plotXPanel.add( xLowLabel );
	xLowField = new JTextField( "-1",3 );
	xLowField.setHorizontalAlignment(JTextField.RIGHT);
	xLowField.addActionListener( this );
	plotXPanel.add( xLowField );
	
	xHighLabel = new JLabel( "X high" );
	plotXPanel.add( xHighLabel );
	xHighField = new JTextField( "1",3 );
	xHighField.setHorizontalAlignment(JTextField.RIGHT);
	xHighField.addActionListener( this );
	plotXPanel.add( xHighField );
	
	yLowLabel = new JLabel( "Y low" );
	plotYPanel.add( yLowLabel );
	yLowField = new JTextField( "-1",3 );
	yLowField.setHorizontalAlignment(JTextField.RIGHT);
	yLowField.addActionListener( this );
	plotYPanel.add( yLowField );
	
	yHighLabel = new JLabel( "Y high" );
	plotYPanel.add( yHighLabel );
	yHighField = new JTextField( "1",3 );
	yHighField.setHorizontalAlignment(JTextField.RIGHT);
	yHighField.addActionListener( this );
	plotYPanel.add( yHighField );
	
	tickIntervalLabel = new JLabel( "Tick interval" );
	plotTickPanel.add( tickIntervalLabel );
	tickIntervalField = new JTextField( "1",2 );
	tickIntervalField.setHorizontalAlignment(JTextField.RIGHT);
	tickIntervalField.addActionListener( this );
	plotTickPanel.add( tickIntervalField );
        */
	
	zoomInButton = new JButton( "Zoom IN" );
	zoomPanel.add( zoomInButton );
	zoomInButton.addActionListener( this );
	
	zoomOutButton = new JButton( "Zoom OUT" );
	zoomPanel.add( zoomOutButton );
	zoomOutButton.addActionListener( this );

	aField.postActionEvent();  
    }


    public void actionPerformed( ActionEvent event ) {

	double aTry, bTry, cTry, dTry, hTry;
	
        DecimalFormat d2, d1;
	d2 = new DecimalFormat ("0.00");
	d1 = new DecimalFormat ("0.0");

	if ( event.getSource() == aField || event.getSource() == bField ) {
	    try {
	        aTry = Double.parseDouble(aField.getText());
	        bTry = Double.parseDouble(bField.getText());
	        cTry = Double.parseDouble(cField.getText());
	        dTry = Double.parseDouble(dField.getText());
	        hTry = Double.parseDouble(hField.getText());
	    }
	    catch (NumberFormatException e) {
	        JOptionPane.showMessageDialog(null,
					  "a, b, c, d and h must be numbers",
					  "Quadratic: Invalid input",
					  JOptionPane.ERROR_MESSAGE);
	        return;
	    }
	    
	    a = aTry;
	    b = bTry;
	    c = cTry;
	    d = dTry;
	    h = hTry;
	    //rSlider.setValue((int)(r*100));  //doesn't invoke handler?
	}
		
//	double xLo, xHi, yLo, yHi, tickInt;
/*	try {
	    xLo = Double.parseDouble(xLowField.getText());
	    xHi = Double.parseDouble(xHighField.getText());
	    yLo = Double.parseDouble(yLowField.getText());
	    yHi = Double.parseDouble(yHighField.getText());
	    tickInt = Double.parseDouble(tickIntervalField.getText());
	}
	catch (NumberFormatException e) {
	    JOptionPane.showMessageDialog(null,
					  "Plotting coordinates must be numbers",
					  "Quadratic plotting: Invalid input",
					  JOptionPane.ERROR_MESSAGE);
	    return;
	}

	if (xLo>xHi || yLo>yHi || tickInt<=0) {
	    JOptionPane.showMessageDialog(null,
					  "Bad plotting coordinates",
					  "Quadratic plotting: Invalid input",
					  JOptionPane.ERROR_MESSAGE);
	    return;
	}
*/
/*	else if ( event.getSource() == aUpButton ) {
	    a += .1;
	    aField.setText(""+d1.format(a));
	    vertSlider.setValue ((int)(a*10));
	}
	else if ( event.getSource() == aDownButton ) {
	    if (a >= .1)
	        a -= .1;
	    else
	    	a = 0;
	    aField.setText(""+d1.format(a));
	    vertSlider.setValue ((int)(a*10));
	}
	else if ( event.getSource() == bUpButton ) {
	    b += .1;
	    bField.setText(""+d1.format(b));
	    horizSlider.setValue ((int)(b*10));
	}
	else if ( event.getSource() == bDownButton ) {
	    if (b >= .1)
	        b -= .1;
	    else
	    	b = 0;
	    bField.setText(""+d1.format(b));
	    horizSlider.setValue ((int)(b*10));
	}
*/
	else if ( event.getSource() == zoomInButton ) {
	    double scale = .9;   //shrink the grid by 10%
	    xLo *= scale;
	    xHi *= scale;
	    yLo *= scale;
	    yHi *= scale;
	}
	else if ( event.getSource() == zoomOutButton ) {
	    double scale = 1.1;   //grow the grid by 10%
	    xLo *= scale;
	    xHi *= scale;
	    yLo *= scale;
	    yHi *= scale;
	}


/*	int numPoints=5000;
	X = new double[numPoints];
        Y = new double[numPoints];
        double dt = 2*Math.PI/numPoints;
        double t=0;
        for (int i=0; i<X.length; i++) {
            //t = i * 2*Math.PI/numPoints; //instead of dt below? no difference...
	    if (graphChoice == 1) {
                X[i] = (1-r)*Math.cos(t) + d*Math.cos((1-r)/r*t);  //hypotrochoid
                Y[i] = (1-r)*Math.sin(t) - d*Math.sin((1-r)/r*t);
	    }
            else if (graphChoice == 2) {
                X[i] = (1+r)*Math.cos(t) - d*Math.cos((1+r)/r*t);  //epitrochoid
                Y[i] = (1+r)*Math.sin(t) - d*Math.sin((1+r)/r*t);
            }
            t += dt;
        }
*/        
        repaint();

    }

/*    public void itemStateChanged( ItemEvent event ) {
	if ( event.getSource() == hypoRadioButton ) {
	    if ( hypoRadioButton.isSelected() ) {
		graphChoice = 1;
		xLabel.setText("x=(1-r)cos \u0398 + d cos (1-r)/r \u0398" );
		yLabel.setText("y=(1-r)sin \u0398 - d sin (1-r)/r \u0398" );
	    }
	}
	else if ( event.getSource() == epiRadioButton ) {
	    if ( epiRadioButton.isSelected() ) {
		graphChoice = 2;
		xLabel.setText("x=(1+r)cos \u0398 - d cos (1+r)/r \u0398" );
		yLabel.setText("y=(1+r)sin \u0398 - d sin (1+r)/r \u0398" );
	    }
	}
	else if ( event.getSource() == traceRadioButton ) {
	    //if ( traceRadioButton.isSelected() ) 
	    trace = !trace;
	    return;
	}
	rField.postActionEvent();  
    }
*/
    public void paint(Graphics g) {

	g.setFont( new Font( "SansSerif", Font.BOLD, 12 ) );
	super.paint(g);
	
	int w=600; //getWidth();     //panel size
	int h=600; //getHeight();    
	double xWidth = xHi - xLo;   //user grid size
	double yHeight = yHi - yLo;
	double xScale = w / xWidth;   //scale user to panel
	double yScale = h / yHeight;
	double xOffset = xLo * xScale - westpanelwidth;
	double yOffset = yLo * yScale + northpanelheight;
        DecimalFormat d3;
	d3 = new DecimalFormat ("0.000");

	g.setColor(Color.WHITE);
	g.fillRect(westpanelwidth,northpanelheight,w,h);

	g.setColor(Color.BLACK);
	
	//int xAxis = (int)(h+yOffset);
	//int yAxis = (int)(-xOffset);

	int x, y, x2, y2;
	//g.setColor(Color.RED);
	g.setColor(Color.BLACK);
	x = (int)(.5 * xScale - xOffset);
	y = h - (int)(.5 * yScale - yOffset);
	x2 = (int)(1 * xScale - xOffset);
	y2 = h - (int)(1 * yScale - yOffset);
	g.drawLine(x,y,x2,y2);
	//g.drawLine(x+1,y+1,x2+1,y2+1);  //doublewidth line
    }

}