/****************************************************************************
** COPYRIGHT (C):    1997 Cay S. Horstmann. All Rights Reserved.
** PROJECT:          Practical OO Development with C++ and Java
** FILE:             shapes.java
** PURPOSE:          test Java graphics shapes
** VERSION           1.0
** PROGRAMMERS:      Cay Horstmann (CSH)
** RELEASE DATE:     3-15-97 (CSH)
** UPDATE HISTORY:
****************************************************************************/

import java.applet.*;
import java.awt.Graphics;
import java.awt.Color;
import java.awt.Font;

public class Shapes extends Applet
{  public void paint(Graphics g)
   {  Shape[] fig = new Shape[6];
      fig[0] = new Point(150, 150);
      fig[1] = new Rectangle(new Point(40, 30), new Point(60, 70));
      fig[2] = new FilledRect(new Point(80, 40), new Point(130, 165),
         Color.red);
      Polygon p = new Polygon(3);
      p.set_corner(0, new Point(350, 100));
      p.set_corner(1, new Point(400, 140));
      p.set_corner(2, new Point(350, 180));
      fig[3] = p;
      fig[4] = new ScalableText(new Point(500, 100), "Hi", 36);
      fig[5] = new Text(new Point(160, 150), "Hello");
      for (int i = 1; i < 20; i++)
      {  for (int j = 0; j < fig.length; j++)
         {  fig[j].plot(g);
            fig[j].scale(new Point(8, 8), 0.9);
         }
      }
   }
}

abstract class Shape
{  abstract void scale(Point center, double scalefactor);
   abstract void plot(Graphics g);
}

class Point extends Shape
{   public Point(int x, int y)
    {   _x = x;
        _y = y;
    }

    public void move(int dx, int dy)
    {   _x += dx;
        _y += dy;
    }

    public void scale(Point center, double scalefactor)
    {   _x = (int)(_x * scalefactor + center._x * (1 - scalefactor));
        _y = (int)(_y * scalefactor + center._y * (1 - scalefactor));
    }

    public int x()
    {   return _x;
    }

    public int y()
    {   return _y;
    }

    public void plot(Graphics g)
    {   g.fillOval(_x - 2, _y - 2, 5, 5);
    }

    private int _x;
    private int _y;
}

class Rectangle extends Shape
{   public Rectangle(Point p, Point q)
    {   _topleft = new Point(Math.min(p.x(), q.x()),
            Math.min(p.y(), q.y()));
        _bottomright = new Point(Math.max(p.x(), q.x()),
            Math.max(p.y(), q.y()));
    }

    public void move(int dx, int dy)
    {   _topleft.move(dx, dy);
        _bottomright.move(dx, dy);
    }

    public void scale(Point center, double s)
    {   _topleft.scale(center, s);
        _bottomright.scale(center, s);
    }

    public void plot(Graphics g)
    {   g.drawRect(_topleft.x(), _topleft.y(),
            _topleft.x() - _bottomright.x(),
            _topleft.y() - _bottomright.y());
    }

    public Point topleft()
    {   return _topleft;
    }

    public Point bottomright()
    {   return _bottomright;
    }

    private Point _topleft; 
    private Point _bottomright;
}

class FilledRect extends Rectangle
{   public FilledRect(Point p, Point q, Color c)
    {   super(p, q);
        _color = c;
    }

    public void plot(Graphics g)
    {   Color c = g.getColor();
        g.setColor(_color);
        g.fillRect(topleft().x(), topleft().y(),
            bottomright().x() - topleft().x(),
            bottomright().y() - topleft().y());
        g.setColor(c);
    }

    private Color _color;
}

class Polygon extends Shape
{   public Polygon(int n)
    {   _corners = new Point[n];
    }

    public void set_corner(int i, Point p)
    {   if(0 <= i && i < _corners.length);
        _corners[i] = p;
    }

    public void move(int dx, int dy)
    {   for(int i = 0; i < _corners.length; i++)
            _corners[i].move(dx, dy);
    }

    public void scale(Point center, double s)
    {   for(int i = 0; i < _corners.length; i++)
            _corners[i].scale(center, s);
    }

    public void plot(Graphics g)
    {   for(int i = 0; i < _corners.length; i++)
        {   int j = (i + 1) % _corners.length;
            g.drawLine(_corners[i].x(), _corners[i].y(),
                _corners[j].x(), _corners[j].y());
        }
    }

    public Point corner(int i)
    {   return _corners[i];
    }

    private Point[] _corners;
}

class Text extends Shape
{   public Text(Point p, String s)
    {   _start = p;
        _text = s;
    }

    public void scale(Point center, double s)
    {   _start.scale(center, s);
    }

    public void plot(Graphics g)
    {   g.drawString(_text, _start.x(), _start.y());
    }

    private Point _start;
    private String _text;
}

class ScalableText extends Text
{   public ScalableText(Point p, String s, double size)
    {   super(p, s);
        _size = size;
    }

    public void scale(Point center, double s)
    {   super.scale(center, s);
        _size = _size * s;
    }

    public void plot(Graphics g)
    {   Font f = g.getFont();
        Font fnew = new Font(f.getName(), f.getStyle(), 
           (int)Math.round(_size));
        g.setFont(fnew);
        super.plot(g);
        g.setFont(f);
    }

    private double _size;
}