/* ===========================================================
 * 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.]
 *
 * -----------------------
 * XYStepAreaRenderer.java
 * -----------------------
 * (C) Copyright 2003-2005, by Matthias Rose and Contributors.
 *
 * Original Author:  Matthias Rose (based on XYAreaRenderer.java);
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * $Id: XYStepAreaRenderer.java,v 1.7.2.3 2005/12/02 11:59:43 mungady Exp $
 *
 * Changes:
 * --------
 * 07-Oct-2003 : Version 1, contributed by Matthias Rose (DG);
 * 10-Feb-2004 : Added some getter and setter methods (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);
 * 06-Jul-2005 : Renamed get/setPlotShapes() --> get/setShapesVisible() (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.Rectangle2D;
import java.io.Serializable;

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.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.util.PublicCloneable;
import org.jfree.util.ShapeUtilities;

/**
 * A step chart renderer that fills the area between the step and the x-axis.
 */
public class XYStepAreaRenderer extends AbstractXYItemRenderer 
                                implements XYItemRenderer, 
                                           Cloneable,
                                           PublicCloneable,
                                           Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -7311560779702649635L;
    
    /** Useful constant for specifying the type of rendering (shapes only). */
    public static final int SHAPES = 1;

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

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

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

    /** A flag that controls whether or not shapes are filled for ALL series. */
    private boolean shapesFilled;

    /** 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;

    /** Area of the complete series */
    protected transient Polygon pArea = null;

    /** 
     * The value on the range axis which defines the 'lower' border of the 
     * area. 
     */
    private double rangeBase;

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

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

    /**
     * Constructs a new renderer.
     * <p>
     * To specify the type of renderer, use one of the constants:
     * AREA, SHAPES 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 XYStepAreaRenderer(int type,
                              XYToolTipGenerator toolTipGenerator, 
                              XYURLGenerator urlGenerator) {

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

        if (type == AREA) {
            this.plotArea = true;
        }
        else if (type == SHAPES) {
            this.shapesVisible = true;
        }
        else if (type == AREA_AND_SHAPES) {
            this.plotArea = true;
            this.shapesVisible = true;
        }
        this.showOutline = false;
    }

    /**
     * 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, and sends a {@link RendererChangeEvent} to all registered 
     * listeners.
     *
     * @param show  the flag.
     */
    public void setOutline(boolean show) {
        this.showOutline = show;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns true if shapes are being plotted by the renderer.
     *
     * @return <code>true</code> if shapes are being plotted by the renderer.
     */
    public boolean getShapesVisible() {
        return this.shapesVisible;
    }
    
    /**
     * Sets the flag that controls whether or not shapes are displayed for each 
     * data item, and sends a {@link RendererChangeEvent} to all registered
     * listeners.
     * 
     * @param flag  the flag.
     */
    public void setShapesVisible(boolean flag) {
        this.shapesVisible = flag;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns the flag that controls whether or not the shapes are filled.
     * 
     * @return A boolean.
     */
    public boolean isShapesFilled() {
        return this.shapesFilled;
    }
    
    /**
     * Sets the 'shapes filled' for ALL series.
     *
     * @param filled  the flag.
     */
    public void setShapesFilled(boolean filled) {
        this.shapesFilled = filled;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * 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;
    }

    /**
     * Sets a flag that controls whether or not areas are drawn for each data 
     * item.
     * 
     * @param flag  the flag.
     */
    public void setPlotArea(boolean flag) {
        this.plotArea = flag;
        notifyListeners(new RendererChangeEvent(this));
    }
    
    /**
     * Returns the value on the range axis which defines the 'lower' border of
     * the area.
     *
     * @return <code>double</code> the value on the range axis which defines 
     *         the 'lower' border of the area.
     */
    public double getRangeBase() {
        return this.rangeBase;
    }

    /**
     * Sets the value on the range axis which defines the default border of the 
     * area.  E.g. setRangeBase(Double.NEGATIVE_INFINITY) lets areas always 
     * reach the lower border of the plotArea. 
     * 
     * @param val  the value on the range axis which defines the default border
     *             of the area.
     */
    public void setRangeBase(double val) {
        this.rangeBase = val;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Initialises the renderer.  Here we calculate the Java2D y-coordinate for
     * zero, since all the bars have their bases fixed at zero.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area inside the axes.
     * @param plot  the plot.
     * @param data  the data.
     * @param info  an optional info collection object to return data back to 
     *              the caller.
     *
     * @return The number of passes required by the renderer.
     */
    public XYItemRendererState initialise(Graphics2D g2,
                                          Rectangle2D dataArea,
                                          XYPlot plot,