/**
 * Copyright 2010-2013 Jingjing Li.
 *
 * This file is part of jplot2d.
 *
 * jplot2d is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 *
 * jplot2d is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with jplot2d. If not, see .
 */
package org.jplot2d.interaction;

import java.awt.Color;
import java.awt.Point;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.Point2D;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import org.jplot2d.element.MovableComponent;
import org.jplot2d.element.PComponent;
import org.jplot2d.transform.PaperTransform;

public class MouseMoveComponentHandler extends MouseDragBehaviorHandler implements
		PropertyChangeListener, VisualFeedbackDrawer {

	private InteractiveComp icomp;

	private MovableComponent pcomp;

	/**
	 * The bounds of component at original location
	 */
	private Shape boundsShape;

	private Point startPoint;

	private Point toPoint;

	public MouseMoveComponentHandler(MouseMoveComponentBehavior behavior, InteractionModeHandler handler) {
		super(behavior, handler);
		icomp = (InteractiveComp) handler.getValue(PlotInteractionManager.INTERACTIVE_COMP_KEY);
	}

	public void propertyChange(PropertyChangeEvent evt) {
		if (evt.getPropertyName().equals(PlotInteractionManager.ACTIVE_COMPONENT_KEY)) {
			PComponent acomp = (PComponent) evt.getNewValue();
			if (acomp instanceof MovableComponent && ((MovableComponent) acomp).isMovable()) {
				handler.putValue(PlotInteractionManager.ACTIVE_COMPONENT_MOVABLE_KEY, Boolean.TRUE);
			} else {
				handler.putValue(PlotInteractionManager.ACTIVE_COMPONENT_MOVABLE_KEY, null);
			}
		}
	}

	@Override
	public boolean canStartDargging(int x, int y) {
		Boolean movable = (Boolean) handler.getValue(PlotInteractionManager.ACTIVE_COMPONENT_MOVABLE_KEY);
		if (movable != null && movable) {
			return true;
		} else {
			return false;
		}
	}

	@Override
	public void draggingStarted(int x, int y) {
		pcomp = (MovableComponent) handler.getValue(PlotInteractionManager.ACTIVE_COMPONENT_KEY);
		/* object selected start move operation */
		startPoint = new Point(x, y);
		boundsShape = getDeviceBounds(pcomp);
	}

	@Override
	public void draggingTo(int x, int y) {
		toPoint = new Point(x, y);
		icomp.repaint();
	}

	@Override
	public void draggingFinished(int x, int y) {
		/* finish move */
		if (startPoint.x == x && startPoint.y == y) {
			return;
		}

		double xoff = x - startPoint.x;
		double yoff = y - startPoint.y;
		PaperTransform pxf = pcomp.getParent().getPaperTransform();
		Point2D dloc = pxf.getPtoD(pcomp.getLocation());
		dloc.setLocation(dloc.getX() + xoff, dloc.getY() + yoff);
		Point2D newLoc = pxf.getDtoP(dloc);
		pcomp.setLocation(newLoc);

		startPoint = null;
		toPoint = null;
		icomp.repaint();
	}

	@Override
	public void draggingCancelled() {

	}

	public void draw(Object g) {

		if (startPoint == null || toPoint == null) {
			return;
		}

		double xoff = toPoint.x - startPoint.x;
		double yoff = toPoint.y - startPoint.y;

		Shape shape = AffineTransform.getTranslateInstance(xoff, yoff).createTransformedShape(boundsShape);

		icomp.drawShape(g, Color.RED.getRGB(), shape);
	}

	private static Shape getDeviceBounds(PComponent comp) {
		return comp.getPaperTransform().getPtoD(comp.getSelectableBounds());
	}

}