/* Copyright 2001 Michael R. Wick */

package Shapes;
import java.awt.*;

public abstract class Shape {
  protected Point theCenter;
  protected Color theColor;

  public Shape(Point p, Color c){
    theCenter = new Point(p);
    theColor = c;
  }

  /* C++-like copy constructor used during Kaleidoscope display */
  public Shape( Shape orig ){
    theCenter = new Point(orig.theCenter) ;
    theColor = orig.theColor;
  }

  public abstract Shape copy();

  /* Helper function to convert degrees to radians. */
  protected double degreesToRadians( int degrees ){
    return (Math.PI / 180.0 * degrees);
  }
  /* Helper function to calculate the distance between two points. */
  protected static int distance(Point p1, Point p2){
    return( (int) Math.sqrt( (p2.x - p1.x) * (p2.x - p1.x) +
                        (p2.y - p1.y) * (p2.y - p1.y)  ));
  }

  public void translateTo(Point p){
    translate(p.x - theCenter.x, p.y - theCenter.y);
  }

  public void flipHorizontalAbout(Point p){
    Point ctr = new Point( theCenter );
    ctr.x = 2 * p.x - ctr.x;
    theCenter = ctr;
    flipBorderHorizontalAbout(p);
  }

  protected abstract void flipBorderHorizontalAbout(Point p);

  public void translate(int dx, int dy){
    Point ctr = new Point(theCenter);
    ctr.x += dx;
    ctr.y += dy;
    theCenter = ctr;
    translateBorder(dx, dy);
  }

  protected abstract void translateBorder(int dx, int dy);

  public void flipVerticalAbout(Point p){
    Point ctr = new Point(theCenter);
    ctr.y = 2 * p.y - ctr.y;
    theCenter = ctr;
    flipBorderVerticalAbout(p);
  }
  protected abstract void flipBorderVerticalAbout(Point p);

  public void flipDiagonalAbout(Point p){
    flipVerticalAbout(p);
    flipHorizontalAbout(p);
  }

  public void draw(Graphics g){
    g.setColor(theColor);
    drawBorder(g);
  }

  public abstract void drawBorder(Graphics g);
  
  protected Point rotateAbout(Point p, Point data, double radians){
    double cos = Math.cos(radians), sin = Math.sin(radians);
    int x, y;
    x = data.x;
    y = data.y;
    return ( new Point((int)(x*cos - y*sin + p.x*(1 - cos) + p.y*sin),
                       (int)(x*sin + y*cos + p.y*(1 - cos) - p.x*sin)) );
  }

  protected static Point translate(Point data, int dx, int dy){
    return (new Point( data.x + dx, data.y + dy ) );
  }

  public void rotateAbout(Point p, int degrees){
    theCenter = rotateAbout(p, theCenter, degreesToRadians(degrees));
    rotateBorderAbout(p, degrees);
  }
  protected abstract void rotateBorderAbout(Point p, int degrees);

  public void setColor(Color c){
    theColor = c;
  }

  public Color getColor(){
    return theColor;
  }

  public Point getCenter(){
    return new Point(theCenter);
  }
}