/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2006, 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
 * USA.  
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * ------------
 * PiePlot.java
 * ------------
 * (C) Copyright 2000-2006, by Andrzej Porebski and Contributors.
 *
 * Original Author:  Andrzej Porebski;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *                   Martin Cordova (percentages in labels);
 *                   Richard Atkinson (URL support for image maps);
 *                   Christian W. Zuckschwerdt;
 *                   Arnaud Lelievre;
 *                   Andreas Schroeder (very minor);
 *
 * $Id: PiePlot.java,v 1.17.2.10 2006/01/27 10:34:07 mungady Exp $
 *
 * Changes (from 21-Jun-2001)
 * --------------------------
 * 21-Jun-2001 : Removed redundant JFreeChart parameter from constructors (DG);
 * 18-Sep-2001 : Updated header (DG);
 * 15-Oct-2001 : Data source classes moved to com.jrefinery.data.* (DG);
 * 19-Oct-2001 : Moved series paint and stroke methods from JFreeChart.java to 
 *               Plot.java (DG);
 * 22-Oct-2001 : Renamed DataSource.java --> Dataset.java etc. (DG);
 * 13-Nov-2001 : Modified plot subclasses so that null axes are possible for 
 *               pie plot (DG);
 * 17-Nov-2001 : Added PieDataset interface and amended this class accordingly,
 *               and completed removal of BlankAxis class as it is no longer 
 *               required (DG);
 * 19-Nov-2001 : Changed 'drawCircle' property to 'circular' property (DG);
 * 21-Nov-2001 : Added options for exploding pie sections and filled out range 
 *               of properties (DG);
 *               Added option for percentages in chart labels, based on code
 *               by Martin Cordova (DG);
 * 30-Nov-2001 : Changed default font from "Arial" --> "SansSerif" (DG);
 * 12-Dec-2001 : Removed unnecessary 'throws' clause in constructor (DG);
 * 13-Dec-2001 : Added tooltips (DG);
 * 16-Jan-2002 : Renamed tooltips class (DG);
 * 22-Jan-2002 : Fixed bug correlating legend labels with pie data (DG);
 * 05-Feb-2002 : Added alpha-transparency to plot class, and updated 
 *               constructors accordingly (DG);
 * 06-Feb-2002 : Added optional background image and alpha-transparency to Plot
 *               and subclasses.  Clipped drawing within plot area (DG);
 * 26-Mar-2002 : Added an empty zoom method (DG);
 * 18-Apr-2002 : PieDataset is no longer sorted (oldman);
 * 23-Apr-2002 : Moved dataset from JFreeChart to Plot.  Added 
 *               getLegendItemLabels() method (DG);
 * 19-Jun-2002 : Added attributes to control starting angle and direction 
 *               (default is now clockwise) (DG);
 * 25-Jun-2002 : Removed redundant imports (DG);
 * 02-Jul-2002 : Fixed sign of percentage bug introduced in 0.9.2 (DG);
 * 16-Jul-2002 : Added check for null dataset in getLegendItemLabels() (DG);
 * 30-Jul-2002 : Moved summation code to DatasetUtilities (DG);
 * 05-Aug-2002 : Added URL support for image maps - new member variable for
 *               urlGenerator, modified constructor and minor change to the 
 *               draw method (RA);
 * 18-Sep-2002 : Modified the percent label creation and added setters for the
 *               formatters (AS);
 * 24-Sep-2002 : Added getLegendItems() method (DG);
 * 02-Oct-2002 : Fixed errors reported by Checkstyle (DG);
 * 09-Oct-2002 : Added check for null entity collection (DG);
 * 30-Oct-2002 : Changed PieDataset interface (DG);
 * 18-Nov-2002 : Changed CategoryDataset to TableDataset (DG);
 * 02-Jan-2003 : Fixed "no data" message (DG);
 * 23-Jan-2003 : Modified to extract data from rows OR columns in 
 *               CategoryDataset (DG);
 * 14-Feb-2003 : Fixed label drawing so that foreground alpha does not apply 
 *               (bug id 685536) (DG);
 * 07-Mar-2003 : Modified to pass pieIndex on to PieSectionEntity and tooltip 
 *               and URL generators (DG);
 * 21-Mar-2003 : Added a minimum angle for drawing arcs 
 *               (see bug id 620031) (DG);
 * 24-Apr-2003 : Switched around PieDataset and KeyedValuesDataset (DG);
 * 02-Jun-2003 : Fixed bug 721733 (DG);
 * 30-Jul-2003 : Modified entity constructor (CZ);
 * 19-Aug-2003 : Implemented Cloneable (DG);
 * 29-Aug-2003 : Fixed bug 796936 (null pointer on setOutlinePaint()) (DG);
 * 08-Sep-2003 : Added internationalization via use of properties 
 *               resourceBundle (RFE 690236) (AL);
 * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
 * 29-Oct-2003 : Added workaround for font alignment in PDF output (DG);
 * 05-Nov-2003 : Fixed missing legend bug (DG);
 * 10-Nov-2003 : Re-added the DatasetChangeListener to constructors (CZ);
 * 29-Jan-2004 : Fixed clipping bug in draw() method (DG);
 * 11-Mar-2004 : Major overhaul to improve labelling (DG);
 * 31-Mar-2004 : Made an adjustment for the plot area when the label generator 
 *               is null.  Fixed null pointer exception when the label 
 *               generator returns null for a label (DG);
 * 06-Apr-2004 : Added getter, setter, serialization and draw support for 
 *               labelBackgroundPaint (AS);
 * 08-Apr-2004 : Added flag to control whether null values are ignored or 
 *               not (DG);
 * 15-Apr-2004 : Fixed some minor warnings from Eclipse (DG);
 * 26-Apr-2004 : Added attributes for label outline and shadow (DG);
 * 04-Oct-2004 : Renamed ShapeUtils --> ShapeUtilities (DG);
 * 04-Nov-2004 : Fixed null pointer exception with new LegendTitle class (DG);
 * 09-Nov-2004 : Added user definable legend item shape (DG);
 * 25-Nov-2004 : Added new legend label generator (DG);
 * 20-Apr-2005 : Added a tool tip generator for legend labels (DG);
 * 26-Apr-2005 : Removed LOGGER (DG);
 * 05-May-2005 : Updated draw() method parameters (DG);
 * 10-May-2005 : Added flag to control visibility of label linking lines, plus
 *               another flag to control the handling of zero values (DG);
 * 08-Jun-2005 : Fixed bug in getLegendItems() method (not respecting flags
 *               for ignoring null and zero values), and fixed equals() method 
 *               to handle GradientPaint (DG);
 * 15-Jul-2005 : Added sectionOutlinesVisible attribute (DG);
 * ------------- JFREECHART 1.0.0 ---------------------------------------------
 * 09-Jan-2006 : Fixed bug 1400442, inconsistent treatment of null and zero
 *               values in dataset (DG);
 *               
 */

package org.jfree.chart.plot;

import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Composite;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Arc2D;
import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Iterator;
import java.util.List;
import java.util.ResourceBundle;

import org.jfree.chart.LegendItem;
import org.jfree.chart.LegendItemCollection;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.entity.PieSectionEntity;
import org.jfree.chart.event.PlotChangeEvent;
import org.jfree.chart.labels.PieSectionLabelGenerator;
import org.jfree.chart.labels.PieToolTipGenerator;
import org.jfree.chart.labels.StandardPieSectionLabelGenerator;
import org.jfree.chart.urls.PieURLGenerator;
import org.jfree.data.DefaultKeyedValues;
import org.jfree.data.KeyedValues;
import org.jfree.data.general.DatasetChangeEvent;
import org.jfree.data.general.DatasetUtilities;
import org.jfree.data.general.PieDataset;
import org.jfree.io.SerialUtilities;
import org.jfree.text.G2TextMeasurer;
import org.jfree.text.TextBlock;
import org.jfree.text.TextBox;
import org.jfree.text.TextUtilities;
import org.jfree.ui.RectangleAnchor;
import org.jfree.ui.RectangleInsets;
import org.jfree.util.ObjectList;
import org.jfree.util.ObjectUtilities;
import org.jfree.util.PaintList;
import org.jfree.util.PaintUtilities;
import org.jfree.util.Rotation;
import org.jfree.util.ShapeUtilities;
import org.jfree.util.StrokeList;

/**
 * A plot that displays data in the form of a pie chart, using data from any 
 * class that implements the {@link PieDataset} interface.
 * <P>
 * Special notes:
 * <ol>
 * <li>the default starting point is 12 o'clock and the pie sections proceed
 * in a clockwise direction, but these settings can be changed;</li>
 * <li>negative values in the dataset are ignored;</li>
 * <li>there are utility methods for creating a {@link PieDataset} from a
 * {@link org.jfree.data.category.CategoryDataset};</li>
 * </ol>
 *
 * @see Plot
 * @see PieDataset
 */
public class PiePlot extends Plot implements Cloneable, Serializable {
    
    /** For serialization. */
    private static final long serialVersionUID = -795612466005590431L;
    
    /** The default interior gap. */
    public static final double DEFAULT_INTERIOR_GAP = 0.25;

    /** The maximum interior gap (currently 40%). */
    public static final double MAX_INTERIOR_GAP = 0.40;

    /** The default starting angle for the pie chart. */
    public static final double DEFAULT_START_ANGLE = 90.0;

    /** The default section label font. */
    public static final Font DEFAULT_LABEL_FONT 
        = new Font("SansSerif", Font.PLAIN, 10);

    /** The default section label paint. */
    public static final Paint DEFAULT_LABEL_PAINT = Color.black;
    
    /** The default section label background paint. */
    public static final Paint DEFAULT_LABEL_BACKGROUND_PAINT 
        = new Color(255, 255, 192);

    /** The default section label outline paint. */
    public static final Paint DEFAULT_LABEL_OUTLINE_PAINT = Color.black;
    
    /** The default section label outline stroke. */
    public static final Stroke DEFAULT_LABEL_OUTLINE_STROKE 
        = new BasicStroke(0.5f);
    
    /** The default section label shadow paint. */
    public static final Paint DEFAULT_LABEL_SHADOW_PAINT = Color.lightGray;
    
    /** The default minimum arc angle to draw. */
    public static final double DEFAULT_MINIMUM_ARC_ANGLE_TO_DRAW = 0.00001;

    /** The dataset for the pie chart. */
    private PieDataset dataset;

    /** The pie index (used by the {@link MultiplePiePlot} class). */
    private int pieIndex;

    /** 
     * The amount of space left around the outside of the pie plot, expressed 
     * as a percentage. 
     */
    private double interiorGap;

    /** Flag determining whether to draw an ellipse or a perfect circle. */
    private boolean circular;

    /** The starting angle. */
    private double startAngle;

    /** The direction for the pie segments. */
    private Rotation direction;

    /** The paint for ALL sections (overrides list). */
    private transient Paint sectionPaint;

    /** The section paint list. */
    private PaintList sectionPaintList;

    /** The base section paint (fallback). */
    private transient Paint baseSectionPaint;

    /** 
     * A flag that controls whether or not an outline is drawn for each
     * section in the plot.
     */
    private boolean sectionOutlinesVisible;

    /** The outline paint for ALL sections (overrides list). */
    private transient Paint sectionOutlinePaint;

    /** The section outline paint list. */
    private PaintList sectionOutlinePaintList;

    /** The base section outline paint (fallback). */
    private transient Paint baseSectionOutlinePaint;

    /** The outline stroke for ALL sections (overrides list). */
    private transient Stroke sectionOutlineStroke;

    /** The section outline stroke list. */
    private StrokeList sectionOutlineStrokeList;

    /** The base section outline stroke (fallback). */
    private transient Stroke baseSectionOutlineStroke;

    /** The shadow paint. */
    private transient Paint shadowPaint = Color.gray;

    /** The x-offset for the shadow effect. */
    private double shadowXOffset = 4.0f;
    
    /** The y-offset for the shadow effect. */
    private double shadowYOffset = 4.0f;
    
    /** The percentage amount to explode each pie section. */
    private ObjectList explodePercentages;
    
    /** The section label generator. */
    private PieSectionLabelGenerator labelGenerator;

    /** The font used to display the section labels. */
    private Font labelFont;

    /** The color used to draw the section labels. */
    private transient Paint labelPaint;
    
    /** The color used to draw the background of the section labels. */
    private transient Paint labelBackgroundPaint;

    /** 
     * The paint used to draw the outline of the section labels 
     * (<code>null</code> permitted). 
     */
    private transient Paint labelOutlinePaint;
    
    /** 
     * The stroke used to draw the outline of the section labels 
     * (<code>null</code> permitted). 
     */
    private transient Stroke labelOutlineStroke;
    
    /** 
     * The paint used to draw the shadow for the section labels 
     * (<code>null</code> permitted). 
     */
    private transient Paint labelShadowPaint;
    
    /** The maximum label width as a percentage of the plot width. */
    private double maximumLabelWidth = 0.20;
    
    /** 
     * The gap between the labels and the plot as a percentage of the plot 
     * width. 
     */
    private double labelGap = 0.05;

    /** A flag that controls whether or not the label links are drawn. */
    private boolean labelLinksVisible;
    
    /** The link margin. */
    private double labelLinkMargin = 0.05;
    
    /** The paint used for the label linking lines. */
    private transient Paint labelLinkPaint = Color.black;
    
    /** The stroke used for the label linking lines. */
    private transient Stroke labelLinkStroke = new BasicStroke(0.5f);
    
    /** The tooltip generator. */
    private PieToolTipGenerator toolTipGenerator;

    /** The URL generator. */
    private PieURLGenerator urlGenerator;
    
    /** The legend label generator. */