package ecologylab.serialization.library.geom;

import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;

import ecologylab.serialization.annotations.simpl_inherit;

/**
 * Encapsulates a Rectangle2D.Double for use in translating to/from XML.
 * 
 * ***WARNING!!!***
 * 
 * Performing transformations (such as setFrame()) on the result of getRect() will cause this object
 * to become out of synch with its underlying Rectangle2D. DO NOT DO THIS!
 * 
 * If other transformation methods are required, either notify me, or implement them yourself. :D
 * 
 * Accessor methods (such as contains()) on the result of getRect() are fine.
 * 
 * @author Zachary O. Toups (zach@ecologylab.net)
 */
@simpl_inherit
public class Rectangle2DDoubleState extends RectangularShape
{
	private Rectangle2D.Double			shape		= null;

	private static final Vector2d[]	normals	=
																					{ new Vector2d(0, -1), new Vector2d(1, 0),
			new Vector2d(0, 1), new Vector2d(-1, 0) };

	public Rectangle2DDoubleState()
	{
		super();
	}

	public Rectangle2DDoubleState(double x, double y, double width, double height)
	{
		super(x, y, width, height);
	}

	/**
	 * Returns an Rectangle2D object represented by this.
	 */
	@Override
	public Rectangle2D.Double shape()
	{
		if (shape == null)
		{
			shape = new Rectangle2D.Double(x, y, w, h);
		}
		else if (shape.x != x || shape.y != y || shape.height != h || shape.width != w)
		{
			shape.setFrame(x, y, w, h);
		}

		return shape;
	}

	@Override
	public boolean contains(Point2D p)
	{
		return shape().contains(p);
	}

	@Override
	public boolean contains(Rectangle2D r)
	{
		return shape().contains(r);
	}

	@Override
	public boolean contains(double x, double y)
	{
		return shape().contains(x, y);
	}

	@Override
	public boolean contains(double x, double y, double w, double h)
	{
		return shape().contains(x, y, w, h);
	}

	@Override
	public Rectangle getBounds()
	{
		return shape().getBounds();
	}

	@Override
	public Rectangle2D getBounds2D()
	{
		return shape().getBounds2D();
	}

	@Override
	public PathIterator getPathIterator(AffineTransform at)
	{
		return shape().getPathIterator(at);
	}

	@Override
	public PathIterator getPathIterator(AffineTransform at, double flatness)
	{
		return shape().getPathIterator(at, flatness);
	}

	@Override
	public boolean intersects(Rectangle2D r)
	{
		return shape().intersects(r);
	}

	@Override
	public boolean intersects(double x, double y, double w, double h)
	{
		return shape().intersects(x, y, w, h);
	}

	/**
	 * Determines the surface normals for each of the sides of the rectangular object. These are
	 * stored in an array, with entry 0 indicating the top (-y) normal, and the others progressing
	 * clockwise from there.
	 * 
	 * The normals are assumed to lie in the X-Y plane.
	 * 
	 * @return a Vector2d array with each entry corresponding to the surface normal of one of the
	 *         sides.
	 */
	public static Vector2d[] getSurfaceNormals()
	{
		return normals;
	}
}