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

 * 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.]

 *

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

 * XYStepAreaRenderer.java

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

 * (C) Copyright 2003, 2004, 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 1.1 2004/08/31 14:49:29 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);

 * 

 */



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;



/**

 * A step chart renderer that fills the area between the step and the x-axis.

 *

 * @author Matthias Rose

 */

public class XYStepAreaRenderer extends AbstractXYItemRenderer 

                                implements XYItemRenderer, 

                                           Cloneable,

                                           PublicCloneable,

                                           Serializable {



    /** 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 plotShapes;



    /** 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();

        setToolTipGenerator(toolTipGenerator);

        setURLGenerator(urlGenerator);



        if (type == AREA) {

            this.plotArea = true;

        }

        else if (type == SHAPES) {

            this.plotShapes = true;

        }

        else if (type == AREA_AND_SHAPES) {

            this.plotArea = true;

            this.plotShapes = 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 getPlotShapes() {

        return this.plotShapes;

    }

    

    /**

     * Sets the flag that controls whether or not shapes are displayed for each data item.

     * 

     * @param flag  the flag.

     */

    public void setPlotShapes(boolean flag) {

        this.plotShapes = 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,

                                          XYDataset data,

                                          PlotRenderingInfo info) {



        return super.initialise(g2, dataArea, plot, data, info);



    }





    /**

     * Draws the visual representation of a single data item.

     *

     * @param g2  the graphics device.

     * @param state  the renderer state.

     * @param dataArea  the area within which the data is being drawn.

     * @param info  collects information about the drawing.

     * @param plot  the plot (can be used to obtain standard color information etc).

     * @param domainAxis  the domain axis.

     * @param rangeAxis  the range axis.

     * @param dataset  the dataset.

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     * @param crosshairState  crosshair information for the plot (<code>null</code> permitted).

     * @param pass  the pass index.

     */

    public void drawItem(Graphics2D g2,

                         XYItemRendererState state,

                         Rectangle2D dataArea,

                         PlotRenderingInfo info,

                         XYPlot plot,

                         ValueAxis domainAxis,

                         ValueAxis rangeAxis,

                         XYDataset dataset,

                         int series,

                         int item,

                         CrosshairState crosshairState,

                         int pass) {

                             

        PlotOrientation orientation = plot.getOrientation();

        

        // Get the item count for the series, so that we can know which is the end of the series.

        int itemCount = dataset.getItemCount(series);



        Paint paint = getItemPaint(series, item);

        Stroke seriesStroke = getItemStroke(series, item);

        g2.setPaint(paint);

        g2.setStroke(seriesStroke);



        // get the data point...

        Number x1 = dataset.getX(series, item);

        Number y1 = dataset.getY(series, item);

        double x = x1.doubleValue();

        double y = y1 == null ? getRangeBase() : y1.doubleValue();

        double transX1 = domainAxis.valueToJava2D(x, dataArea, plot.getDomainAxisEdge());

        double transY1 = rangeAxis.valueToJava2D(y, dataArea, plot.getRangeAxisEdge());

                                                          

        // avoid possible sun.dc.pr.PRException: endPath: bad path

        transY1 = restrictValueToDataArea(transY1, plot, dataArea);         



        if (this.pArea == null && y1 != null) {



            // Create a new Area for the series

            this.pArea = new Polygon();

        

            // start from Y = rangeBase

            double transY2 = rangeAxis.valueToJava2D(

                getRangeBase(), dataArea, plot.getRangeAxisEdge()

            );

        

            // avoid possible sun.dc.pr.PRException: endPath: bad path

            transY2 = restrictValueToDataArea(transY2, plot, dataArea);         

        

            // The first point is (x, this.baseYValue)

            if (orientation == PlotOrientation.VERTICAL) {

                this.pArea.addPoint((int) transX1, (int) transY2);

            }

            else if (orientation == PlotOrientation.HORIZONTAL) {

                this.pArea.addPoint((int) transY2, (int) transX1);

            }

        }



        double transX0 = 0;

        double transY0 = restrictValueToDataArea(getRangeBase(), plot, dataArea);           

        

        Number x0 = null;

        Number y0 = null;

        if (item > 0) {

            // get the previous data point...

            x0 = dataset.getX(series, item - 1);

            y0 = y1 == null ? null : dataset.getY(series, item - 1);



            x = x0.doubleValue();

            y = y0 == null ? getRangeBase() : y0.doubleValue();

            transX0 = domainAxis.valueToJava2D(x, dataArea, plot.getDomainAxisEdge());

            transY0 = rangeAxis.valueToJava2D(y, dataArea, plot.getRangeAxisEdge());



            // avoid possible sun.dc.pr.PRException: endPath: bad path

            transY0 = restrictValueToDataArea(transY0, plot, dataArea);

                        

            if (y1 == null) {

                // NULL value -> insert point on base line

                // instead of 'step point'

                transX1 = transX0;

                transY0 = transY1;          

            }

            if (transY0 != transY1) {

                // not just a horizontal bar but need to perform a 'step'.

                if (orientation == PlotOrientation.VERTICAL) {

                    this.pArea.addPoint((int) transX1, (int) transY0);                       

                }

                else if (orientation == PlotOrientation.HORIZONTAL) {

                    this.pArea.addPoint((int) transY0, (int) transX1);

                }

            }

        }           



        Shape shape = null;

        if (y1 != null) {

            // Add each point to Area (x, y)

            if (orientation == PlotOrientation.VERTICAL) {

                this.pArea.addPoint((int) transX1, (int) transY1);

            }

            else if (orientation == PlotOrientation.HORIZONTAL) {

                this.pArea.addPoint((int) transY1, (int) transX1);

            }



            if (getPlotShapes()) {

                shape = getItemShape(series, item);

                if (orientation == PlotOrientation.VERTICAL) {

                    shape = createTransformedShape(shape, transX1, transY1);

                }

                else if (orientation == PlotOrientation.HORIZONTAL) {

                    shape = createTransformedShape(shape, transY1, transX1);

                }

                if (isShapesFilled()) {

                    g2.fill(shape);

                }   

                else {

                    g2.draw(shape);

                }   

            }

            else {

                if (orientation == PlotOrientation.VERTICAL) {

                    shape = new Rectangle2D.Double(transX1 - 2, transY1 - 2, 4.0, 4.0);

                }

                else if (orientation == PlotOrientation.HORIZONTAL) {

                    shape = new Rectangle2D.Double(transY1 - 2, transX1 - 2, 4.0, 4.0);

                }

            }

        }



        // Check if the item is the last item for the series or if it

        // is a NULL value and number of items > 0.  We can't draw an area for a single point.

        if (getPlotArea() && item > 0 && this.pArea != null 

                          && (item == (itemCount - 1) || y1 == null)) {



            double transY2 = rangeAxis.valueToJava2D(

                getRangeBase(), dataArea, plot.getRangeAxisEdge()

            );



            // avoid possible sun.dc.pr.PRException: endPath: bad path

            transY2 = restrictValueToDataArea(transY2, plot, dataArea);         



            if (orientation == PlotOrientation.VERTICAL) {

                // Add the last point (x,0)

                this.pArea.addPoint((int) transX1, (int) transY2);

            }

            else if (orientation == PlotOrientation.HORIZONTAL) {

                // Add the last point (x,0)

                this.pArea.addPoint((int) transY2, (int) transX1);

            }



            // fill the polygon

            g2.fill(this.pArea);



            // draw an outline around the Area.

            if (isOutline()) {

                g2.setStroke(plot.getOutlineStroke());

                g2.setPaint(plot.getOutlinePaint());

                g2.draw(this.pArea);

            }



            // start new area when needed (see above)

            this.pArea = null;

        }



        // do we need to update the crosshair values?

        if (y1 != null) {

            updateCrosshairValues(

                crosshairState, x1.doubleValue(), y1.doubleValue(), transX1, transY1, orientation

            );

        }



        // collect entity and tool tip information...

        if (state.getInfo() != null) {

            EntityCollection entities = state.getInfo().getOwner().getEntityCollection();

            if (entities != null && shape != null) {

                String tip = null;

                XYToolTipGenerator generator = getToolTipGenerator(series, item);

                if (generator != null) {

                    tip = generator.generateToolTip(dataset, series, item);

                }

                String url = null;

                if (getURLGenerator() != null) {

                    url = getURLGenerator().generateURL(dataset, series, item);

                }

                XYItemEntity entity = new XYItemEntity(shape, dataset, series, item, tip, url);

                entities.addEntity(entity);

            }

        }

    }



    /**

     * Returns a clone of the renderer.

     * 

     * @return A clone.

     * 

     * @throws CloneNotSupportedException  if the renderer cannot be cloned.

     */

    public Object clone() throws CloneNotSupportedException {

        return super.clone();

    }

    

    /**

     * Helper method which returns a value if it lies

     * inside the visible dataArea and otherwise the corresponding

     * coordinate on the border of the dataArea. The PlotOrientation

     * is taken into account. 

     * Useful to avoid possible sun.dc.pr.PRException: endPath: bad path

     * which occurs when trying to draw lines/shapes which in large part

     * lie outside of the visible dataArea.

     * 

     * @param value the value which shall be 

     * @param dataArea  the area within which the data is being drawn.

     * @param plot  the plot (can be used to obtain standard color information etc).

     * @return <code>double</code> value inside the data area.

     */

    protected static double restrictValueToDataArea(double value, 

                                                    XYPlot plot, 

                                                    Rectangle2D dataArea) {

        double min = 0;

        double max = 0;

        if (plot.getOrientation() == PlotOrientation.VERTICAL) {

            min = dataArea.getMinY();

            max = dataArea.getMaxY();

        } 

        else if (plot.getOrientation() ==  PlotOrientation.HORIZONTAL) {

            min = dataArea.getMinX();

            max = dataArea.getMaxX();

        }       

        if (value < min) {

            value = min;

        }

        else if (value > max) {

            value = max;

        }

        return value;

    }



}

