/* ===========================================================

 * JFreeChart : a free chart library for the Java(tm) platform

 * ===========================================================

 *

 * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.

 *

 * Project Info:  http://www.jfree.org/jfreechart/index.html

 *

 * This library 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 2.1 of the License, or (at your option) any later version.

 *

 * This library 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 Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License along with this

 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 *

 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 

 * in the United States and other countries.]

 *

 * ------------------------

 * XYPointerAnnotation.java

 * ------------------------

 * (C) Copyright 2003, 2004, by Object Refinery Limited.

 *

 * Original Author:  David Gilbert (for Object Refinery Limited);

 * Contributor(s):   -;

 *

 * $Id: XYPointerAnnotation.java,v 1.1 2004/08/31 14:28:00 mungady Exp $

 *

 * Changes:

 * --------

 * 21-May-2003 : Version 1 (DG);

 * 10-Jun-2003 : Changed BoundsAnchor to TextAnchor (DG);

 * 02-Jul-2003 : Added accessor methods and simplified constructor (DG);

 * 19-Aug-2003 : Implemented Cloneable (DG);

 * 13-Oct-2003 : Fixed bug where arrow paint is not set correctly (DG);

 * 21-Jan-2004 : Update for renamed method in ValueAxis (DG);

 *

 */



package org.jfree.chart.annotations;



import java.awt.BasicStroke;

import java.awt.Color;

import java.awt.Graphics2D;

import java.awt.Paint;

import java.awt.Stroke;

import java.awt.geom.GeneralPath;

import java.awt.geom.Line2D;

import java.awt.geom.Rectangle2D;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.Serializable;



import org.jfree.chart.axis.ValueAxis;

import org.jfree.chart.plot.Plot;

import org.jfree.chart.plot.PlotOrientation;

import org.jfree.chart.plot.XYPlot;

import org.jfree.io.SerialUtilities;

import org.jfree.text.TextUtilities;

import org.jfree.ui.RectangleEdge;



/**

 * An arrow and label that can be placed on an {@link org.jfree.chart.plot.XYPlot}.  The arrow is

 * drawn at a user-definable angle so that it points towards the (x, y) location for the 

 * annotation.  

 * <p>

 * The arrow length (and its offset from the (x, y) location) is controlled by the

 * tip radius and the base radius attributes.  Imagine two circles around the (x, y) coordinate: 

 * the inner circle defined by the tip radius, and the outer circle defined by the base radius.  

 * Now, draw the arrow starting at some point on the outer circle (the point is determined by the

 * angle), with the arrow tip being drawn at a corresponding point on the inner circle.

 * <p>

 * See the <code>MarkerDemo1.java</code> source file in the JFreeChart distribution for an example.

 *

 */

public class XYPointerAnnotation extends XYTextAnnotation 

                                 implements XYAnnotation, Cloneable, Serializable {



    /** The default tip radius (in Java2D units). */

    public static final double DEFAULT_TIP_RADIUS = 10.0;

    

    /** The default base radius (in Java2D units). */

    public static final double DEFAULT_BASE_RADIUS = 30.0;

    

    /** The default label offset (in Java2D units). */

    public static final double DEFAULT_LABEL_OFFSET = 3.0;

    

    /** The default arrow length (in Java2D units). */

    public static final double DEFAULT_ARROW_LENGTH = 5.0;



    /** The default arrow width (in Java2D units). */

    public static final double DEFAULT_ARROW_WIDTH = 3.0;

    

    /** The angle of the arrow's line (in radians). */

    private double angle;



    /** The radius from the (x, y) point to the tip of the arrow (in Java2D units). */

    private double tipRadius;



    /** The radius from the (x, y) point to the start of the arrow line (in Java2D units). */

    private double baseRadius;



    /** The length of the arrow head (in Java2D units). */

    private double arrowLength;



    /** The arrow width (in Java2D units, per side). */

    private double arrowWidth;

    

    /** The arrow stroke. */

    private transient Stroke arrowStroke;



    /** The arrow paint. */

    private transient Paint arrowPaint;

    

    /** The radius from the base point to the anchor point for the label. */

    private double labelOffset;



    /**

     * Creates a new label and arrow annotation.

     *

     * @param label  the label (<code>null</code> permitted).

     * @param x  the x-coordinate (measured against the chart's domain axis).

     * @param y  the y-coordinate (measured against the chart's range axis).

     * @param angle  the angle of the arrow's line (in radians).

     */

    public XYPointerAnnotation(String label, double x, double y, double angle) {



        super(label, x, y);

        this.angle = angle;

        this.tipRadius = DEFAULT_TIP_RADIUS;

        this.baseRadius = DEFAULT_BASE_RADIUS;

        this.arrowLength = DEFAULT_ARROW_LENGTH;

        this.arrowWidth = DEFAULT_ARROW_WIDTH;

        this.labelOffset = DEFAULT_LABEL_OFFSET;

        this.arrowStroke = new BasicStroke(1.0f);

        this.arrowPaint = Color.black;



    }

    

    /**

     * Returns the angle of the arrow.

     * 

     * @return The angle (in radians).

     */

    public double getAngle() {

        return this.angle;

    }

    

    /**

     * Sets the angle of the arrow.

     * 

     * @param angle  the angle (in radians).

     */

    public void setAngle(double angle) {

        this.angle = angle;

    }

    

    /**

     * Returns the tip radius.

     * 

     * @return The tip radius (in Java2D units).

     */

    public double getTipRadius() {

        return this.tipRadius;

    }

    

    /**

     * Sets the tip radius.

     * 

     * @param radius  the radius (in Java2D units).

     */

    public void setTipRadius(double radius) {

        this.tipRadius = radius;

    }

    

    /**

     * Sets the base radius.

     * 

     * @return The base radius (in Java2D units).

     */

    public double getBaseRadius() {

        return this.baseRadius;

    }

    

    /**

     * Sets the base radius.

     * 

     * @param radius  the radius (in Java2D units).

     */

    public void setBaseRadius(double radius) {

        this.baseRadius = radius;

    }



    /**

     * Sets the label offset.

     * 

     * @return The label offset (in Java2D units).

     */

    public double getLabelOffset() {

        return this.labelOffset;

    }

    

    /**

     * Sets the label offset (from the arrow base, continuing in a straight line, in Java2D units).

     * 

     * @param offset  the offset (in Java2D units).

     */

    public void setLabelOffset(double offset) {

        this.labelOffset = offset;

    }

    

    /**

     * Returns the arrow length.

     * 

     * @return The arrow length.

     */

    public double getArrowLength() {

        return this.arrowLength;

    }

    

    /**

     * Sets the arrow length.

     * 

     * @param length  the length.

     */

    public void setArrowLength(double length) {

        this.arrowLength = length;

    }



    /**

     * Returns the arrow width.

     * 

     * @return The arrow width (in Java2D units).

     */

    public double getArrowWidth() {

        return this.arrowWidth;

    }

    

    /**

     * Sets the arrow width.

     * 

     * @param width  the width (in Java2D units).

     */

    public void setArrowWidth(double width) {

        this.arrowWidth = width;

    }

    

    /** 

     * Returns the stroke used to draw the arrow line.

     * 

     * @return The arrow stroke (never <code>null</code>).

     */

    public Stroke getArrowStroke() {

        return this.arrowStroke;

    }



    /** 

     * Sets the stroke used to draw the arrow line.

     * 

     * @param stroke  the stroke (<code>null</code> not permitted).

     */

    public void setArrowStroke(Stroke stroke) {

        if (stroke == null) {

            throw new IllegalArgumentException("Null 'stroke' not permitted.");

        }

        this.arrowStroke = stroke;

    }

    

    /**

     * Sets the paint used for the arrow.

     * 

     * @return The arrow paint (never <code>null</code>).

     */

    public Paint getArrowPaint() {

        return this.arrowPaint;

    }

    

    /**

     * Sets the paint used for the arrow.

     * 

     * @param paint  the arrow paint (<code>null</code> not permitted).

     */

    public void setArrowPaint(Paint paint) {

        this.arrowPaint = paint;

    }

    

    /**

     * Draws the annotation.

     *

     * @param g2  the graphics device.

     * @param plot  the plot.

     * @param dataArea  the data area.

     * @param domainAxis  the domain axis.

     * @param rangeAxis  the range axis.

     */

    public void draw(Graphics2D g2, XYPlot plot, Rectangle2D dataArea,

                     ValueAxis domainAxis, ValueAxis rangeAxis) {



        PlotOrientation orientation = plot.getOrientation();

        RectangleEdge domainEdge = Plot.resolveDomainAxisLocation(

            plot.getDomainAxisLocation(), orientation

        );

        RectangleEdge rangeEdge = Plot.resolveRangeAxisLocation(

            plot.getRangeAxisLocation(), orientation

        );

        double j2DX = domainAxis.valueToJava2D(getX(), dataArea, domainEdge);

        double j2DY = rangeAxis.valueToJava2D(getY(), dataArea, rangeEdge);



        double startX = j2DX + Math.cos(this.angle) * this.baseRadius;

        double startY = j2DY + Math.sin(this.angle) * this.baseRadius;



        double endX = j2DX + Math.cos(this.angle) * this.tipRadius;

        double endY = j2DY + Math.sin(this.angle) * this.tipRadius;



        double arrowBaseX = endX + Math.cos(this.angle) * this.arrowLength;

        double arrowBaseY = endY + Math.sin(this.angle) * this.arrowLength;



        double arrowLeftX = arrowBaseX + Math.cos(this.angle + Math.PI / 2.0) * this.arrowWidth;

        double arrowLeftY = arrowBaseY + Math.sin(this.angle + Math.PI / 2.0) * this.arrowWidth;



        double arrowRightX = arrowBaseX - Math.cos(this.angle + Math.PI / 2.0) * this.arrowWidth;

        double arrowRightY = arrowBaseY - Math.sin(this.angle + Math.PI / 2.0) * this.arrowWidth;



        GeneralPath arrow = new GeneralPath();

        arrow.moveTo((float) endX, (float) endY);

        arrow.lineTo((float) arrowLeftX, (float) arrowLeftY);

        arrow.lineTo((float) arrowRightX, (float) arrowRightY);

        arrow.closePath();



        g2.setStroke(this.arrowStroke);

        g2.setPaint(this.arrowPaint);

        Line2D line = new Line2D.Double(startX, startY, endX, endY);

        g2.draw(line);

        g2.fill(arrow);



        // draw the label

        g2.setFont(getFont());

        g2.setPaint(getPaint());

        double labelX = j2DX + Math.cos(this.angle) * (this.baseRadius + this.labelOffset);

        double labelY = j2DY + Math.sin(this.angle) * (this.baseRadius + this.labelOffset);

        TextUtilities.drawAlignedString(

            getText(), 

            g2, 

            (float) labelX, 

            (float) labelY,

            getTextAnchor()

        );



    }

    

    /**

     * Tests this annotation for equality with an object.

     * 

     * @param object  the object to test against.

     * 

     * @return <code>true</code> or <code>false</code>.

     */

    public boolean equals(Object object) {

        

        if (object == null) {

            return false;

        }

        

        if (object == this) {

            return true;

        }

        

        if (object instanceof XYPointerAnnotation) {

        

            XYPointerAnnotation a = (XYPointerAnnotation) object;

            boolean b0 = (this.angle == a.angle);

            boolean b1 = (this.tipRadius == a.tipRadius);

            boolean b2 = (this.baseRadius == a.baseRadius);

            boolean b3 = (this.arrowLength == a.arrowLength);

            boolean b4 = (this.arrowWidth == a.arrowWidth);

            boolean b5 = (this.arrowPaint.equals(a.arrowPaint));

            boolean b6 = (this.arrowStroke.equals(a.arrowStroke));

            boolean b7 = (this.labelOffset == a.labelOffset);

            return b0 && b1 && b2 && b3 && b4 && b5 && b6 && b7;

        }

       

        return false;

        

    }

    

    /**

     * Returns a clone of the annotation.

     * 

     * @return A clone.

     * 

     * @throws CloneNotSupportedException  if the annotation can't be cloned.

     */

    public Object clone() throws CloneNotSupportedException {

        return super.clone();

    }



    /**

     * Provides serialization support.

     *

     * @param stream  the output stream.

     *

     * @throws IOException if there is an I/O error.

     */

    private void writeObject(ObjectOutputStream stream) throws IOException {

        stream.defaultWriteObject();

        SerialUtilities.writePaint(this.arrowPaint, stream);

        SerialUtilities.writeStroke(this.arrowStroke, stream);

    }



    /**

     * Provides serialization support.

     *

     * @param stream  the input stream.

     *

     * @throws IOException  if there is an I/O error.

     * @throws ClassNotFoundException  if there is a classpath problem.

     */

    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {

        stream.defaultReadObject();

        this.arrowPaint = SerialUtilities.readPaint(stream);

        this.arrowStroke = SerialUtilities.readStroke(stream);

    }



}

