/* 
 *  =========================================================================
 *  This program create a frame with a panel and canvas, and draws a simple
 *  sinusoidal graph on the canvas.
 * 
 *  Written By : Mark Austin                                    November 1997 
 *  =========================================================================
 */ 

import java.awt.*;
import java.awt.event.*;

public class TestGraph extends Frame {

    // The main method creates an instance of the class.

    public static void main( String args[] ) {
       TestGraph t = new TestGraph();
    }

    // Define window frame.

    public TestGraph() {
       setLayout (new BorderLayout());
       GraphicsScreen gs = new GraphicsScreen();

       // Create lower panel and buttons.

       Panel p1 = new Panel();

       Button b1 = new Button("Quit");
       b1.addMouseListener(new ControlPanelListener(b1, gs ));
       p1.add( b1 );

       Button b2 = new Button("Clear");
       b2.addMouseListener(new ControlPanelListener(b2, gs ));
       p1.add( b2 );

       Button b3 = new Button("Draw Graph");
       b3.addMouseListener(new ControlPanelListener(b3, gs ));
       p1.add( b3 );

       // Position canvas and panel within the frame.

       add("Center", gs );
       add("South",  p1 );

       // Set frame title and size. Display the frame.

       setTitle("Time-history response of SDOF System"); 
       setSize(600,400);                                 
       show();                                           
    }
}

class GraphicsScreen extends Canvas {
    private Dimension size;
    private Graphics    gs;

    public void paint ( Graphics g ) {
        size = getSize();
        clear();
    }
    
    public void clear () {
        int iBorder = 25;

        // Get graphics and fill in background ....

        gs = getGraphics();
        gs.setColor( Color.black);
        gs.fillRect(  0, 0, size.width-1,       size.height-1 );

        // Draw center patch ....

        gs.setColor( Color.white);
        gs.fillRect( iBorder, iBorder, size.width-2*iBorder, size.height-2*iBorder );
    }

    public void gsDraw () {
        int iBorder1 = 25;
        int iBorder2 = 30;
        int iScaleX  = 10; //  Maximum value of x coordinate.
        int iScaleY  = 40; //  Range of y-coordinate values.
        int iMinX    = iBorder2 + iBorder1; 
        int iMinY    = iBorder2 + iBorder1; 
        int iMaxX    = size.width  - iBorder2 - iBorder1; 
        int iMaxY    = size.height - iBorder2 - iBorder1; 
        int iDeltaX  = iMaxX-iMinX;
        int iDeltaY  = iMaxY-iMinY;

        // Get graphics and draw graph background ....

        gs = getGraphics();
        gs.setColor( Color.red );
        gs.fillRect( iBorder1, iBorder1,
                     size.width-2*iBorder1, size.height-2*iBorder1 );
        gs.setColor( Color.white );
        gs.fillRect( iBorder2, iBorder2,
                     size.width-2*iBorder2, size.height-2*iBorder2 );

        // Draw axis in black

        gs.setColor(Color.black);
        gs.drawLine( iMinX, iMinY+iDeltaY/2, iMaxX, iMinY+iDeltaY/2 );
        gs.drawLine( iMinX, iMinY, iMinX, iMaxY);

        gs.setColor(Color.red); // Change color to red for plotting

        // Calculate the original point in pixel system

        double dYorg  = FunctionToPlot(0);
        int iPrevXpt  = iMinX;
        int iPrevYpt  = (int) ((iMinY + (iDeltaY)/2 - (iDeltaY)*dYorg/iScaleY));

        // Plot function by looping over x values : problem coordinates are
        // converted to pixel coordinates for plotting.

        for (int iXpt = iMinX ; iXpt < iMaxX + 1 ; iXpt++ ) {
             double dX = (double) ((iXpt - iMinX)*((double) iScaleX /
                                   (double) iDeltaX));
             double dY = FunctionToPlot( dX );
             int  iYpt = (int) (iMinY + (iDeltaY)/2 - (iDeltaY)*dY/iScaleY);

             gs.drawLine( iPrevXpt, iPrevYpt, iXpt, iYpt);
             iPrevXpt = iXpt;
             iPrevYpt = iYpt;
        }

        // Print title for plot....

        gs.setColor(Color.black); // Print title of plot in black.
        gs.drawString("y(t) = 10.cos(10.t) + 10.sin(10.t)/sqrt(10)",
                      iMinX + iBorder1, iMinY + iBorder1);
    }

    // The function to plot

    public double FunctionToPlot( double dX ) {
    double dXint = 10.0;
    double dVint = 10;
    double dW    = Math.sqrt(10.0);

       return (double)( dXint*Math.cos(dW*dX) + dVint*Math.sin(dW*dX)/dW );
    }
}

class ControlPanelListener extends MouseAdapter {
    private Button button;
    private GraphicsScreen graphics;

    public ControlPanelListener( Button b, GraphicsScreen gs ) {
        graphics = gs;
        button   = b;
    }

    public void mouseReleased(MouseEvent e) {
        String s = new String(button.getLabel());

        if( s.compareTo("Quit") == 0 ) {
            System.out.println("Quit");
            System.exit(0);
        }
        if( s.compareTo("Clear") == 0 ) {
            graphics.clear();
        }
        if( s.compareTo("Draw Graph") == 0 ) {
            graphics.gsDraw();
        }
    }
}