package horstmann.ch08_graphed;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;

/**
   A circular node that is filled with a color.
 */
@SuppressWarnings("serial")
public class CircleNode implements Node
{
  /**
      Construct a circle node with a given size and color.
      @param aColor the fill color
   */
  public CircleNode(Color aColor)
  {
    size = DEFAULT_SIZE;
    x = 0;
    y = 0;
    color = aColor;
  }

  public Object clone()
  {
    try
    {
      return super.clone();
    }
    catch (CloneNotSupportedException exception)
    {
      return null;
    }
  }

  public void draw(Graphics2D g2)
  {
    Ellipse2D circle = new Ellipse2D.Double(
        x, y, size, size);
    Color oldColor = g2.getColor();
    g2.setColor(color);
    g2.fill(circle);
    g2.setColor(oldColor);
    g2.draw(circle);
  }

  public void translate(double dx, double dy)
  {
    x += dx;
    y += dy;
  }

  public boolean contains(Point2D p)
  {
    Ellipse2D circle = new Ellipse2D.Double(
        x, y, size, size);
    return circle.contains(p);
  }

  public Rectangle2D getBounds()
  {
    return new Rectangle2D.Double(
        x, y, size, size);
  }

  public Point2D getConnectionPoint(Point2D other)
  {
    double centerX = x + size / 2;
    double centerY = y + size / 2;
    double dx = other.getX() - centerX;
    double dy = other.getY() - centerY;
    double distance = Math.sqrt(dx * dx + dy * dy);
    if (distance == 0) return other;
    else return new Point2D.Double(
        centerX + dx * (size / 2) / distance,
        centerY + dy * (size / 2) / distance);
  }

  private double x;
  private double y;
  private double size;
  private Color color;
  private static final int DEFAULT_SIZE = 20;
}