/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2005, 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.]
 *
 * -------------------
 * XYAreaRenderer.java
 * -------------------
 * (C) Copyright 2002-2005, by Hari and Contributors.
 *
 * Original Author:  Hari (ourhari@hotmail.com);
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *                   Richard Atkinson;
 *                   Christian W. Zuckschwerdt;
 *
 * $Id: XYAreaRenderer.java,v 1.12.2.5 2005/12/22 15:53:05 mungady Exp $
 *
 * Changes:
 * --------
 * 03-Apr-2002 : Version 1, contributed by Hari.  This class is based on the 
 *               StandardXYItemRenderer class (DG);
 * 09-Apr-2002 : Removed the translated zero from the drawItem method - 
 *               overridden the initialise() method to calculate it (DG);
 * 30-May-2002 : Added tool tip generator to constructor to match super 
 *               class (DG);
 * 25-Jun-2002 : Removed unnecessary local variable (DG);
 * 05-Aug-2002 : Small modification to drawItem method to support URLs for HTML
 *               image maps (RA);
 * 01-Oct-2002 : Fixed errors reported by Checkstyle (DG);
 * 07-Nov-2002 : Renamed AreaXYItemRenderer --> XYAreaRenderer (DG);
 * 25-Mar-2003 : Implemented Serializable (DG);
 * 01-May-2003 : Modified drawItem() method signature (DG);
 * 27-Jul-2003 : Made line and polygon properties protected rather than 
 *               private (RA);
 * 30-Jul-2003 : Modified entity constructor (CZ);
 * 20-Aug-2003 : Implemented Cloneable and PublicCloneable (DG);
 * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
 * 07-Oct-2003 : Added renderer state (DG);
 * 08-Dec-2003 : Modified hotspot for chart entity (DG);
 * 10-Feb-2004 : Changed the drawItem() method to make cut-and-paste overriding
 *               easier.  Also moved state class into this class (DG);
 * 25-Feb-2004 : Replaced CrosshairInfo with CrosshairState.  Renamed 
 *               XYToolTipGenerator --> XYItemLabelGenerator (DG);
 * 15-Jul-2004 : Switched getX() with getXValue() and getY() with 
 *               getYValue() (DG);
 * 11-Nov-2004 : Now uses ShapeUtilities to translate shapes (DG);
 * 19-Jan-2005 : Now accesses primitives only from dataset (DG);
 * 21-Mar-2005 : Override getLegendItem() and equals() methods (DG);
 * 20-Apr-2005 : Use generators for legend tooltips and URLs (DG);
 * 
 */

package org.jfree.chart.renderer.xy;

import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Polygon;
import java.awt.Shape;
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.LegendItem;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.entity.XYItemEntity;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.labels.XYSeriesLabelGenerator;
import org.jfree.chart.labels.XYToolTipGenerator;
import org.jfree.chart.plot.CrosshairState;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.urls.XYURLGenerator;
import org.jfree.data.xy.XYDataset;
import org.jfree.io.SerialUtilities;
import org.jfree.util.PublicCloneable;
import org.jfree.util.ShapeUtilities;

/**
 * Area item renderer for an {@link XYPlot}.  This class can draw (a) shapes at
 * each point, or (b) lines between points, or (c) both shapes and lines, 
 * or (d) filled areas, or (e) filled areas and shapes.
 */
public class XYAreaRenderer extends AbstractXYItemRenderer 
                            implements XYItemRenderer, 
                                       Cloneable,
                                       PublicCloneable,
                                       Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -4481971353973876747L;
    
    /**
     * A state object used by this renderer.
     */
    static class XYAreaRendererState extends XYItemRendererState {
        
        /** Working storage for the area under one series. */
        public Polygon area;
        
        /** Working line that can be recycled. */
        public Line2D line;
        
        /**
         * Creates a new state.
         * 
         * @param info  the plot rendering info.
         */
        public XYAreaRendererState(PlotRenderingInfo info) {
            super(info);
            this.area = new Polygon();
            this.line = new Line2D.Double();
        }
        
    }
    
    /** Useful constant for specifying the type of rendering (shapes only). */
    public static final int SHAPES = 1;

    /** Useful constant for specifying the type of rendering (lines only). */
    public static final int LINES = 2;

    /** 
     * Useful constant for specifying the type of rendering (shapes and lines).
     */
    public static final int SHAPES_AND_LINES = 3;

    /** Useful constant for specifying the type of rendering (area only). */
    public static final int AREA = 4;

    /** 
     * Useful constant for specifying the type of rendering (area and shapes). 
     */
    public static final int AREA_AND_SHAPES = 5;

    /** A flag indicating whether or not shapes are drawn at each XY point. */
    private boolean plotShapes;

    /** A flag indicating whether or not lines are drawn between XY points. */
    private boolean plotLines;

    /** A flag indicating whether or not Area are drawn at each XY point. */
    private boolean plotArea;

    /** A flag that controls whether or not the outline is shown. */
    private boolean showOutline;

    /** 
     * The shape used to represent an area in each legend item (this should 
     * never be <code>null</code>). 
     */
    private transient Shape legendArea;

    /**
     * Constructs a new renderer.
     */
    public XYAreaRenderer() {
        this(AREA);
    }

    /**
     * Constructs a new renderer.
     *
     * @param type  the type of the renderer.
     */
    public XYAreaRenderer(int type) {
        this(type, null, null);
    }

    /**
     * Constructs a new renderer.
     * <p>
     * To specify the type of renderer, use one of the constants: SHAPES, LINES,
     * SHAPES_AND_LINES, AREA or AREA_AND_SHAPES.
     *
     * @param type  the type of renderer.
     * @param toolTipGenerator  the tool tip generator to use 
     *                          (<code>null</code> permitted).
     * @param urlGenerator  the URL generator (<code>null</code> permitted).
     */
    public XYAreaRenderer(int type, XYToolTipGenerator toolTipGenerator, 
                          XYURLGenerator urlGenerator) {

        super();
        setBaseToolTipGenerator(toolTipGenerator);
        setURLGenerator(urlGenerator);

        if (type == SHAPES) {
            this.plotShapes = true;
        }
        if (type == LINES) {
            this.plotLines = true;
        }
        if (type == SHAPES_AND_LINES) {
            this.plotShapes = true;
            this.plotLines = true;
        }
        if (type == AREA) {
            this.plotArea = true;
        }
        if (type == AREA_AND_SHAPES) {
            this.plotArea = true;
            this.plotShapes = true;
        }
        this.showOutline = false;
        GeneralPath area = new GeneralPath();
        area.moveTo(0.0f, -4.0f);
        area.lineTo(3.0f, -2.0f);
        area.lineTo(4.0f, 4.0f);
        area.lineTo(-4.0f, 4.0f);
        area.lineTo(-3.0f, -2.0f);
        area.closePath();
        this.legendArea = area;

    }

    /**
     * Returns a flag that controls whether or not outlines of the areas are 
     * drawn.
     *
     * @return The flag.
     */
    public boolean isOutline() {
        return this.showOutline;
    }

    /**
     * Sets a flag that controls whether or not outlines of the areas are drawn.
     *
     * @param show  the flag.
     */
    public void setOutline(boolean show) {
        this.showOutline = show;
    }

    /**
     * Returns true if shapes are being plotted by the renderer.
     *
     * @return <code>true</code> if shapes are being plotted by the renderer.
     */
    public boolean getPlotShapes() {
        return this.plotShapes;
    }

    /**
     * Returns true if lines are being plotted by the renderer.
     *
     * @return <code>true</code> if lines are being plotted by the renderer.
     */
    public boolean getPlotLines() {
        return this.plotLines;
    }

    /**
     * Returns true if Area is being plotted by the renderer.
     *
     * @return <code>true</code> if Area is being plotted by the renderer.
     */
    public boolean getPlotArea() {
        return this.plotArea;
    }

    /**
     * Returns the shape used to represent an area in the legend.
     * 
     * @return The legend area (never <code>null</code>).
     */
    public Shape getLegendArea() {
        return this.legendArea;   
    }
    
    /**
     * Sets the shape used as an area in each legend item and sends a 
     * {@link RendererChangeEvent} to all registered listeners.
     * 
     * @param area  the area (<code>null</code> not permitted).
     */
    public void setLegendArea(Shape area) {
        if (area == null) {
            throw new IllegalArgumentException("Null 'area' argument.");   
        }
        this.legendArea = area;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Initialises the renderer and returns a state object that should be 
     * passed to all subsequent calls to the drawItem() method.
     *