//QuadraticDriver.java

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

public class QuadraticDriver extends JApplet implements ActionListener, ListSelectionListener {
                            
    private JLabel aLabel, bLabel, cLabel, zoomLabel;
    private JTextField aField, bField, cField;
    private JButton anotherButton;
    private JButton sortButton;
    private JButton clearButton;
    private JList quadraticJList;
    private JSlider zoomSlider;
    private ArrayList quadraticArrayList;
    private GraphingPanel quadraticGraphingPanel;

    public void init() {  

	Container container = getContentPane();  
	container.setLayout(new GridLayout(1,2)); 

	JPanel leftPanel = new JPanel();
	leftPanel.setLayout(new BorderLayout());  

	JPanel northPanel = new JPanel();
	northPanel.setLayout(new GridLayout(2,1));

	JPanel topNorthPanel = new JPanel();
	topNorthPanel.setLayout(new FlowLayout());

	aLabel = new JLabel( "a" );
	topNorthPanel.add( aLabel );
	aField = new JTextField( 3 );
	topNorthPanel.add( aField );
	
	bLabel = new JLabel( "b" );
	topNorthPanel.add( bLabel );
	bField = new JTextField( 3 );
	topNorthPanel.add( bField );
	
	cLabel = new JLabel( "c" );
	topNorthPanel.add( cLabel );
	cField = new JTextField( 3 );
	topNorthPanel.add( cField );
	
	anotherButton = new JButton( "New quadratic" );
	topNorthPanel.add( anotherButton );
	anotherButton.addActionListener( this );

	northPanel.add(topNorthPanel);

	JPanel bottomNorthPanel = new JPanel();
	bottomNorthPanel.setLayout(new FlowLayout());

	sortButton = new JButton( "Sort" );
	bottomNorthPanel.add( sortButton );
	sortButton.addActionListener( this );

	clearButton = new JButton( "Clear All" );
	bottomNorthPanel.add( clearButton );
	clearButton.addActionListener( this );

	northPanel.add(bottomNorthPanel);

	leftPanel.add(northPanel,BorderLayout.NORTH);

	quadraticArrayList = new ArrayList();

	quadraticJList = new JList(quadraticArrayList.toArray());  
	quadraticJList.setVisibleRowCount(30);
	quadraticJList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
	quadraticJList.addListSelectionListener( this );

	leftPanel.add(new JScrollPane(quadraticJList),BorderLayout.CENTER);

	container.add(leftPanel);

	JPanel rightPanel = new JPanel();
	rightPanel.setLayout(new BorderLayout());  //??why need explicitly

	JPanel rightTopPanel = new JPanel();
	rightTopPanel.setLayout(new GridLayout(2,1));

	zoomLabel = new JLabel( "Zoom" );
	rightTopPanel.add(zoomLabel);

	zoomSlider = new JSlider( SwingConstants.HORIZONTAL, 0, 100, 10 );
	rightTopPanel.add(zoomSlider);

	rightPanel.add(rightTopPanel,BorderLayout.NORTH);

	quadraticGraphingPanel = new GraphingPanel();
	rightPanel.add(quadraticGraphingPanel,BorderLayout.CENTER);

	container.add(rightPanel);

	zoomSlider.addChangeListener(
	        new ChangeListener() { 
		    public void stateChanged( ChangeEvent e ) {
			//			//....??
		    }
		}
	);

    }


    public void actionPerformed( ActionEvent event ) {

	if (event.getSource() == anotherButton) {
	    double a, b, c;
	    
	    try {
		a = Double.parseDouble(aField.getText() );
		b = Double.parseDouble(bField.getText());
		c = Double.parseDouble(cField.getText());

		Quadratic quad;
		try {
		    quad = new Quadratic(a,b,c);

		    quadraticArrayList.add(quad);
		    quadraticJList.setListData(quadraticArrayList.toArray()); 
		    quadraticGraphingPanel.drawQuadratic(quad);

		} catch (InvalidQuadraticException e) {
		    JOptionPane.showMessageDialog(null,e.getMessage());
		}
	    }
	    catch (NumberFormatException e) {
		JOptionPane.showMessageDialog(null,"a, b, and c must be numbers");
	    }
	}
	else if (event.getSource() == sortButton) {
	    Collections.sort(quadraticArrayList,new QuadraticComparator());  
	    quadraticJList.setListData(quadraticArrayList.toArray()); 
	}
	else if (event.getSource() == clearButton) {
	    quadraticArrayList.clear();
	    aField.setText("");
	    bField.setText("");
	    cField.setText("");
	    quadraticJList.setListData(quadraticArrayList.toArray()); 
	}
    }

    public void valueChanged( ListSelectionEvent event ) {
	if ( event.getSource() == quadraticJList ) {
            int i = quadraticJList.getSelectedIndex();  
	    if (i>=0) {    //kludge ....
		Quadratic quad = (Quadratic)(quadraticArrayList.get(i));
		quadraticGraphingPanel.drawQuadratic(quad);
		aField.setText(""+quad.getA());
		bField.setText(""+quad.getB());
		cField.setText(""+quad.getC());
	    }
	}				  
    }

}

//??? should this be public?  private?  inner?
class GraphingPanel extends JPanel {

    Quadratic refQuad;

    public void paintComponent(Graphics g) {

	super.paintComponent(g);   
	int w=getWidth();     
	int h=getHeight();    
	g.drawLine(0,h/2,w,h/2);
	g.drawLine(w/2,0,w/2,h);
	
	double a, b, c, x1, x2;

	if (refQuad != null) {
	    a = refQuad.getA();
	    b = refQuad.getB();
	    c = refQuad.getC();
	    switch (refQuad.getNumberSolutions()) { 
	    case 2: x2 = refQuad.getx2();
	    case 1: x1 = refQuad.getx1();
	    }
	    //quick and dirty plotting
	    g.setColor(Color.RED);
	    int y;
	    for (int x=-w/2; x<w/2; x++) {
		y = -(int)(a*x*x + b*x + c);
		g.drawLine(x+w/2,y+h/2,x+w/2,y+h/2);
	    }
	    //g.drawString(""+refQuad,20,60);
	}
    }
    
    public void drawQuadratic(Quadratic quad) {
	
	refQuad = quad;
	repaint();    
    }
}