/* ======================================
 * JFreeChart : a free Java chart library
 * ======================================
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 * Project Lead:  David Gilbert (david.gilbert@object-refinery.com);
 *
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors.
 *
 * 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.
 *
 * ---------
 * Plot.java
 * ---------
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Sylvain Vieujot;
 *                   Jeremy Bowman;
 *                   Andreas Schneider;
 *                   Gideon Krause;
 *
 * $Id: Plot.java,v 1.12 2003/09/03 15:08:50 mungady Exp $
 *
 * Changes (from 21-Jun-2001)
 * --------------------------
 * 21-Jun-2001 : Removed redundant JFreeChart parameter from constructors (DG);
 * 18-Sep-2001 : Updated header info and fixed DOS encoding problem (DG);
 * 19-Oct-2001 : Moved series paint and stroke methods from JFreeChart class (DG);
 * 23-Oct-2001 : Created renderer for LinePlot class (DG);
 * 07-Nov-2001 : Changed type names for ChartChangeEvent (DG);
 *               Tidied up some Javadoc comments (DG);
 * 13-Nov-2001 : Changes to allow for null axes on plots such as PiePlot (DG);
 *               Added plot/axis compatibility checks (DG);
 * 12-Dec-2001 : Changed constructors to protected, and removed unnecessary 'throws' clauses (DG);
 * 13-Dec-2001 : Added tooltips (DG);
 * 22-Jan-2002 : Added handleClick(...) method, as part of implementation for crosshairs (DG);
 *               Moved tooltips reference into ChartInfo class (DG);
 * 23-Jan-2002 : Added test for null axes in chartChanged(...) method, thanks to Barry Evans for
 *               the bug report (number 506979 on SourceForge) (DG);
 *               Added a zoom(...) method (DG);
 * 05-Feb-2002 : Updated setBackgroundPaint(), setOutlineStroke() and setOutlinePaint() to better
 *               handle null values, as suggested by Sylvain Vieujot (DG);
 * 06-Feb-2002 : Added background image, plus alpha transparency for background and foreground (DG);
 * 06-Mar-2002 : Added AxisConstants interface (DG);
 * 26-Mar-2002 : Changed zoom method from empty to abstract (DG);
 * 23-Apr-2002 : Moved dataset from JFreeChart class (DG);
 * 11-May-2002 : Added ShapeFactory interface for getShape() methods, contributed by Jeremy
 *               Bowman (DG);
 * 28-May-2002 : Fixed bug in setSeriesPaint(int, Paint) for subplots (AS);
 * 25-Jun-2002 : Removed redundant imports (DG);
 * 30-Jul-2002 : Added 'no data' message for charts with null or empty datasets (DG);
 * 21-Aug-2002 : Added code to extend series array if necessary (refer to SourceForge bug
 *               id 594547 for details) (DG);
 * 17-Sep-2002 : Fixed bug in getSeriesOutlineStroke(...) method, reported by Andreas
 *               Schroeder (DG);
 * 23-Sep-2002 : Added getLegendItems() abstract method (DG);
 * 24-Sep-2002 : Removed firstSeriesIndex, subplots now use their own paint settings, there is a
 *               new mechanism for the legend to collect the legend items (DG);
 * 27-Sep-2002 : Added dataset group (DG);
 * 14-Oct-2002 : Moved listener storage into EventListenerList.  Changed some abstract methods
 *               to empty implementations (DG);
 * 28-Oct-2002 : Added a getBackgroundImage() method (DG);
 * 21-Nov-2002 : Added a plot index for identifying subplots in combined and overlaid charts (DG);
 * 22-Nov-2002 : Changed all attributes from 'protected' to 'private'.  Added dataAreaRatio
 *               attribute from David M O'Donnell's code (DG);
 * 09-Jan-2003 : Integrated fix for plot border contributed by Gideon Krause (DG);
 * 17-Jan-2003 : Moved to com.jrefinery.chart.plot (DG);
 * 23-Jan-2003 : Removed one constructor (DG);
 * 26-Mar-2003 : Implemented Serializable (DG);
 * 14-Jul-2003 : Moved the dataset and secondaryDataset attributes to the CategoryPlot and
 *               XYPlot classes (DG);
 * 21-Jul-2003 : Moved DrawingSupplier from CategoryPlot and XYPlot up to this class (DG);
 * 20-Aug-2003 : Implemented Cloneable (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.Image;
import java.awt.Insets;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.font.FontRenderContext;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import javax.swing.event.EventListenerList;

import org.jfree.chart.ChartRenderingInfo;
import org.jfree.chart.LegendItemCollection;
import org.jfree.chart.axis.AxisConstants;
import org.jfree.chart.axis.AxisLocation;
import org.jfree.chart.event.AxisChangeEvent;
import org.jfree.chart.event.AxisChangeListener;
import org.jfree.chart.event.PlotChangeEvent;
import org.jfree.chart.event.PlotChangeListener;
import org.jfree.data.DatasetChangeEvent;
import org.jfree.data.DatasetChangeListener;
import org.jfree.data.DatasetGroup;
import org.jfree.io.SerialUtilities;
import org.jfree.ui.Align;
import org.jfree.ui.RectangleEdge;
import org.jfree.util.ObjectUtils;

/**
 * The base class for all plots in JFreeChart.  The {@link org.jfree.chart.JFreeChart} class
 * delegates the drawing of axes and data to the plot.  This base class provides facilities common
 * to most plot types.
 *
 * @author David Gilbert
 */
public abstract class Plot implements AxisChangeListener,
                                      DatasetChangeListener,
                                      AxisConstants,
                                      Serializable {

    /** Useful constant representing zero. */
    public static final Number ZERO = new Integer(0);

    /** The default insets. */
    public static final Insets DEFAULT_INSETS = new Insets(4, 8, 4, 8);

    /** The default outline stroke. */
    public static final Stroke DEFAULT_OUTLINE_STROKE = new BasicStroke(1);

    /** The default outline color. */
    public static final Paint DEFAULT_OUTLINE_PAINT = Color.gray;

    /** The default foreground alpha transparency. */
    public static final float DEFAULT_FOREGROUND_ALPHA = 1.0f;

    /** The default background alpha transparency. */
    public static final float DEFAULT_BACKGROUND_ALPHA = 1.0f;

    /** The default background color. */
    public static final Paint DEFAULT_BACKGROUND_PAINT = Color.white;

    /** The minimum width at which the plot should be drawn. */
    public static final int MINIMUM_WIDTH_TO_DRAW = 10;

    /** The minimum height at which the plot should be drawn. */
    public static final int MINIMUM_HEIGHT_TO_DRAW = 10;

    /** The parent plot (<code>null</code> if this is the root plot). */
    private Plot parent;

    /** The dataset group (to be used for thread synchronisation). */
    private DatasetGroup datasetGroup;

    /** The message to display if no data is available. */
    private String noDataMessage;

    /** The font used to display the 'no data' message. */
    private Font noDataMessageFont;

    /** The paint used to draw the 'no data' message. */
    private transient Paint noDataMessagePaint;

    /** Amount of blank space around the plot area. */
    private Insets insets;

    /** The Stroke used to draw an outline around the plot. */
    private transient Stroke outlineStroke;

    /** The Paint used to draw an outline around the plot. */
    private transient Paint outlinePaint;

    /** An optional color used to fill the plot background. */
    private transient Paint backgroundPaint;

    /** An optional image for the plot background. */
    private transient Image backgroundImage;  // not currently serialized

    /** The alignment for the background image. */
    private int backgroundImageAlignment = Align.FIT;

    /** The alpha-transparency for the plot. */
    private float foregroundAlpha;

    /** The alpha transparency for the background paint. */
    private float backgroundAlpha;

    /** The drawing supplier. */
    private DrawingSupplier drawingSupplier;

    /** Storage for registered change listeners. */
    private transient EventListenerList listenerList;

    /** Defines dataArea rectangle as the ratio formed from dividing height by width
     * (of the dataArea).  Modifies plot area calculations.
     * ratio>0 will attempt to layout the plot so that the
     * dataArea.height/dataArea.width = ratio.
     * ratio<0 will attempt to layout the plot so that the
     * dataArea.height/dataArea.width in plot units (not java2D units as when ratio>0)
     * = -1.*ratio.
     */         //dmo
    private double dataAreaRatio = 0.0;  //zero when the parameter is not set

    /**
     * Creates a new plot.
     */
    protected Plot() {

        this.parent = null;

        this.insets = DEFAULT_INSETS;
        this.backgroundPaint = DEFAULT_BACKGROUND_PAINT;
        this.backgroundAlpha = DEFAULT_BACKGROUND_ALPHA;
        this.backgroundImage = null;
        this.outlineStroke = DEFAULT_OUTLINE_STROKE;
        this.outlinePaint = DEFAULT_OUTLINE_PAINT;
        this.foregroundAlpha = DEFAULT_FOREGROUND_ALPHA;

        this.noDataMessage = null;
        this.noDataMessageFont = new Font("SansSerif", Font.PLAIN, 12);
        this.noDataMessagePaint = Color.black;

        this.drawingSupplier = new DefaultDrawingSupplier();
        
        this.listenerList = new EventListenerList();

    }

    /**
     * Returns the dataset group for the plot.
     *
     * @return the dataset group.
     */
    public DatasetGroup getDatasetGroup() {
        return this.datasetGroup;
    }

    /**
     * Sets the dataset group.
     *
     * @param group  the dataset group.
     */
    protected void setDatasetGroup(DatasetGroup group) {
        this.datasetGroup = group;
    }

    /**
     * Returns the string that is displayed when the dataset is empty or <code>null</code>.
     *
     * @return The 'no data' message (<code>null</code> possible).
     */
    public String getNoDataMessage() {
        return this.noDataMessage;
    }

    /**
     * Sets the message that is displayed when the dataset is empty or null.
     *
     * @param message  the message (null permitted).
     */
    public void setNoDataMessage(String message) {
        this.noDataMessage = message;
    }

    /**
     * Returns the font used to display the 'no data' message.
     *
     * @return the font.
     */
    public Font getNoDataMessageFont() {
        return this.noDataMessageFont;
    }

    /**
     * Sets the font used to display the 'no data' message.
     *
     * @param font  the font.
     */
    public void setNoDataMessageFont(Font font) {
        this.noDataMessageFont = font;
    }

    /**
     * Returns the paint used to display the 'no data' message.
     *
     * @return the paint.
     */
    public Paint getNoDataMessagePaint() {
        return this.noDataMessagePaint;
    }

    /**
     * Sets the paint used to display the 'no data' message.
     *
     * @param paint  the paint.
     */
    public void setNoDataMessagePaint(Paint paint) {
        this.noDataMessagePaint = paint;
    }

    /**
     * Returns a short string describing the plot type.
     * <P>
     * Note: this gets used in the chart property editing user interface,
     * but there needs to be a better mechanism for identifying the plot type.
     *
     * @return a short string describing the plot type.
     */
    public abstract String getPlotType();

    /**
     * Returns the parent plot (or null if this plot is not part of a combined plot).
     *
     * @return the parent plot.
     */
    public Plot getParent() {
        return this.parent;
    }

    /**
     * Sets the parent plot.
     *
     * @param parent  the parent plot.
     */
    public void setParent(Plot parent) {
        this.parent = parent;
    }

    /**
     * Returns the root plot.
     *
     * @return The root plot.
     */
    public Plot getRootPlot() {

        Plot p = getParent();
        if (p == null) {
            return this;
        }
        else {
            return p.getRootPlot();
        }

    }

    /**
     * Returns true if this plot is part of a combined plot structure.
     *
     * @return <code>true</code> if this plot is part of a combined plot structure.
     */
    public boolean isSubplot() {
        return (getParent() != null);
    }