//******************************************************************************
// problem2.java:	Applet   for MAS962 ps#2
//
// Author: Ingeborg Endter       9/19/97
//******************************************************************************
import java.applet.*;
import java.awt.*;

//==============================================================================
// Main Class for applet problem2
//
//==============================================================================
public class problem2 extends Applet
{
    private int numRows = 24,                 // Set # of rows for the canvas here
                numCols = 80,                 //   likewise, # of columns
                lastX = 0,
                lastY = 0,
                lastRow = 0,
                lastCol = 0,
                startX = 0,
                startY = 0,
                cellWidth = 0,
                cellHeight = 0,
                canvasWidth = 0,
                canvasHeight = 0;
    Font font= new Font("Courier", Font.PLAIN, 8); // and font
 
    public static int APPLETWIDTH = 540;
    public static int APPLETHEIGHT = 382;  


	public void init()
	{
    	resize(APPLETWIDTH, APPLETHEIGHT);
        setFont(font);
        cellWidth = APPLETWIDTH / numCols;
        cellHeight = APPLETHEIGHT / numRows;
        canvasWidth = cellWidth * numCols;
        canvasHeight = cellHeight * numRows;
        setBackground(Color.white);
    }

	// Place additional applet clean up code here.  destroy() is called when
	// when you applet is terminating and being unloaded.
	//-------------------------------------------------------------------------
	public void destroy()
	{
	}

	// problem2 Paint Handler
	//--------------------------------------------------------------------------
	public void paint(Graphics g)
	{
        g.setColor(Color.black);
        g.drawRect(0,0, canvasWidth+1, canvasHeight+1);        
	}

    
	//--------------------------------------------------------------------------
	public void clear(Graphics g)
	{
        g.setColor(Color.white);
        g.clearRect(1,1, canvasWidth-1, canvasHeight-1); 
    }


    public int getFontAscent()            
    {
        Graphics g = getGraphics();
        FontMetrics fm = g.getFontMetrics();
        int ascent =  fm.getAscent();
        return ascent;
    }
		
		    
	// MOUSE SUPPORT:

    //		The mouseEnter() method is called when the mouse first enters 
    //      this component.
	//--------------------------------------------------------------------------
	public boolean mouseEnter(Event evt, int x, int y)
    {    //Don't acknowledge any events outside the canvas area
	    if (x < canvasWidth && y < canvasHeight)
	    {
	        lastX = x;
            lastY = y;
        }
        return true;
	}


	//		The mouseMove() method is called when the mouse is moved inside 
    //      this component with the mouse button not pushed
	//--------------------------------------------------------------------------
	public boolean mouseMove(Event evt, int x, int y)
    {    //Don't acknowledge any events outside the canvas area
	    if (x < canvasWidth && y < canvasHeight)
	    {
	        lastX = x;
            lastY = y;
        }
        return true;
	}


   public boolean keyDown(Event  evt, int  key)
   {      // Based on the cell size...
          // compute which cell the mouse cursor is in; 
          //    row and col numbering begins at 0
        lastCol = lastX / cellWidth;
        lastRow = lastY / cellHeight;

          // then compute the starting point for drawing in the cell  
        startX = (lastCol * cellWidth);
        startY = (lastRow * cellHeight) + getFontAscent();

          // draw the character at the baseline of the cell
        Graphics g = getGraphics();
        char[] ca = {(char)key};
          // Handle only letters a to z
        if (Character.isUpperCase(ca[0]) || Character.isLowerCase(ca[0]))           
            g.drawChars(ca, 0, 1, startX, startY);
          // or numbers 0 to 9
        else if (Character.isDigit(ca[0]) )
            g.drawChars(ca, 0, 1, startX, startY);
        else if (key == 27)
            clear(g);
        return true;
    }
		    
}  //end class problem2