// file:    AppletGrid.java
// author:  Robert Keller
// purpose: Extend class Grid for drawing in an applet.

/**
 * Class AppletGrid provides an extension of Grid for the purpose of
 * drawing the Grid in an applet.  It adds drawing commands to the basic
 * Grid class.
 */

import java.awt.*;

class AppletGrid extends Grid
{
/**
 * Color used in applet to draw Grid
 */

public static Color gridColor = Color.red;


/**
 * Color used in applet to draw spam
 */

public static Color spamColor = Color.blue;


/**
 * Color used in applet to draw DESC end
 */

public static Color DESCendColor = Color.red;


/**
 * Color used in applet to draw DESC body
 */

public static Color DESCbodyColor = Color.green;


/** 
 * Construct a grid from a Sample, which includes the relevant size
 * information and spam settins.
 *
 * @param sample the Sample specifying Grid size and contents
 */

public AppletGrid(Sample sample)
  {
  super(sample.getRows(), sample.getCols());
  setSpam(sample.elements());
  }


/** 
 * Set spam on Pairs in an enumeration of Pairs.
 *
 * @param pairs the enumeration of Pairs given
 */

public void setSpam(java.util.Enumeration pairs)
  {
  while( pairs.hasMoreElements() )
    {
    setSpam((Pair)pairs.nextElement());
    }
  }


/**
 * Draw the grid in the Graphics, at a specified pair offsets and
 * with a certain feature size.
 */

void draw(Graphics graphics, int xOffset, int yOffset, int size)
  {
  for( int row = 0; row < rows; row++ )
    {
    for( int col = 0; col < cols; col++ )
      {
      int x = xOffset+col*size;
      int y = yOffset+row*size;

      graphics.setColor(gridColor);
      graphics.drawRect(x, y, size, size);

      switch( get(row, col) )
        {
        case SPAM:     drawSpam(graphics, x, y, size);         break;
        case DESChead: drawDESCendCell(graphics, x, y, size);  break;
        case DESCbody: drawDESCbodyCell(graphics, x, y, size); break;
        }
      }
    }
  }


/**
 * Draw spam at the specified position.
 */

void drawSpam(Graphics graphics, int x, int y, int size)
  {
  graphics.setColor(spamColor);
  graphics.drawLine(x, y, x+size, y+size);
  graphics.drawLine(x+size, y, x, y+size);
  }


/**
 * Draw a end (head or tail) cell of a DESC.
 */

void drawDESCendCell(Graphics graphics, int x, int y, int size)
  {
  graphics.setColor(DESCendColor);
  graphics.fillOval(x+1, y+1, size-2, size-2);
  }


/**
 * Draw a body cell of a DESC.
 */

void drawDESCbodyCell(Graphics graphics, int x, int y, int size)
  {
  graphics.setColor(DESCbodyColor);
  graphics.fillOval(x+1, y+1, size-2, size-2);
  }


}