/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-present, by David Gilbert 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.
 *
 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
 * Other names may be trademarks of their respective owners.]
 *
 * ------------------
 * XYDotRenderer.java
 * ------------------
 * (C) Copyright 2002-present, by David Gilbert.
 *
 * Original Author:  David Gilbert;
 * Contributor(s):   Christian W. Zuckschwerdt;
 *
 */

package org.jfree.chart.renderer.xy;

import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

import org.jfree.chart.LegendItem;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.event.RendererChangeEvent;
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.ui.RectangleEdge;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.PublicCloneable;
import org.jfree.chart.util.SerialUtils;
import org.jfree.chart.util.ShapeUtils;
import org.jfree.data.xy.XYDataset;

/**
 * A renderer that draws a small dot at each data point for an {@link XYPlot}.
 * The example shown here is generated by the
 * {@code ScatterPlotDemo4.java} program included in the JFreeChart
 * demo collection:
 * <br><br>
 * <img src="doc-files/XYDotRendererSample.png" alt="XYDotRendererSample.png">
 */
public class XYDotRenderer extends AbstractXYItemRenderer
        implements XYItemRenderer, PublicCloneable {

    /** For serialization. */
    private static final long serialVersionUID = -2764344339073566425L;

    /** The dot width. */
    private int dotWidth;

    /** The dot height. */
    private int dotHeight;

    /**
     * The shape that is used to represent an item in the legend.
     */
    private transient Shape legendShape;

    /**
     * Constructs a new renderer.
     */
    public XYDotRenderer() {
        super();
        this.dotWidth = 1;
        this.dotHeight = 1;
        this.legendShape = new Rectangle2D.Double(-3.0, -3.0, 6.0, 6.0);
    }

    /**
     * Returns the dot width (the default value is 1).
     *
     * @return The dot width.
     *
     * @see #setDotWidth(int)
     */
    public int getDotWidth() {
        return this.dotWidth;
    }

    /**
     * Sets the dot width and sends a {@link RendererChangeEvent} to all
     * registered listeners.
     *
     * @param w  the new width (must be greater than zero).
     *
     * @throws IllegalArgumentException if {@code w} is less than one.
     * 
     * @see #getDotWidth()
     */
    public void setDotWidth(int w) {
        if (w < 1) {
            throw new IllegalArgumentException("Requires w > 0.");
        }
        this.dotWidth = w;
        fireChangeEvent();
    }

    /**
     * Returns the dot height (the default value is 1).
     *
     * @return The dot height.
     * 
     * @see #setDotHeight(int)
     */
    public int getDotHeight() {
        return this.dotHeight;
    }

    /**
     * Sets the dot height and sends a {@link RendererChangeEvent} to all
     * registered listeners.
     *
     * @param h  the new height (must be greater than zero).
     *
     * @throws IllegalArgumentException if {@code h} is less than one.
     *
     * @see #getDotHeight()
     */
    public void setDotHeight(int h) {
        if (h < 1) {
            throw new IllegalArgumentException("Requires h > 0.");
        }
        this.dotHeight = h;
        fireChangeEvent();
    }

    /**
     * Returns the shape used to represent an item in the legend.
     *
     * @return The legend shape (never {@code null}).
     *
     * @see #setLegendShape(Shape)
     */
    public Shape getLegendShape() {
        return this.legendShape;
    }

    /**
     * Sets the shape used as a line in each legend item and sends a
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param shape  the shape ({@code null} not permitted).
     *
     * @see #getLegendShape()
     */
    public void setLegendShape(Shape shape) {
        Args.nullNotPermitted(shape, "shape");
        this.legendShape = shape;
        fireChangeEvent();
    }

    /**
     * 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 (horizontal) axis.
     * @param rangeAxis  the range (vertical) 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} permitted).
     * @param pass  the pass index.
     */
    @Override
    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) {

        // do nothing if item is not visible
        if (!getItemVisible(series, item)) {
            return;
        }

        // get the data point...
        double x = dataset.getXValue(series, item);
        double y = dataset.getYValue(series, item);
        double adjx = (this.dotWidth - 1) / 2.0;
        double adjy = (this.dotHeight - 1) / 2.0;
        if (!Double.isNaN(y)) {
            RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
            RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
            double transX = domainAxis.valueToJava2D(x, dataArea,
                    xAxisLocation) - adjx;
            double transY = rangeAxis.valueToJava2D(y, dataArea, yAxisLocation)
                    - adjy;

            g2.setPaint(getItemPaint(series, item));
            PlotOrientation orientation = plot.getOrientation();
            if (orientation == PlotOrientation.HORIZONTAL) {
                g2.fillRect((int) transY, (int) transX, this.dotHeight,
                        this.dotWidth);
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                g2.fillRect((int) transX, (int) transY, this.dotWidth,
                        this.dotHeight);
            }

            int datasetIndex = plot.indexOf(dataset);
            updateCrosshairValues(crosshairState, x, y, datasetIndex,
                    transX, transY, orientation);
        }

    }

    /**
     * Returns a legend item for the specified series.
     *
     * @param datasetIndex  the dataset index (zero-based).
     * @param series  the series index (zero-based).
     *
     * @return A legend item for the series (possibly {@code null}).
     */
    @Override
    public LegendItem getLegendItem(int datasetIndex, int series) {

        // if the renderer isn't assigned to a plot, then we don't have a
        // dataset...
        XYPlot plot = getPlot();
        if (plot == null) {
            return null;
        }

        XYDataset dataset = plot.getDataset(datasetIndex);
        if (dataset == null) {
            return null;
        }

        LegendItem result = null;
        if (getItemVisible(series, 0)) {
            String label = getLegendItemLabelGenerator().generateLabel(dataset,
                    series);
            String description = label;
            String toolTipText = null;
            if (getLegendItemToolTipGenerator() != null) {
                toolTipText = getLegendItemToolTipGenerator().generateLabel(
                        dataset, series);
            }
            String urlText = null;
            if (getLegendItemURLGenerator() != null) {
                urlText = getLegendItemURLGenerator().generateLabel(
                        dataset, series);
            }
            Paint fillPaint = lookupSeriesPaint(series);
            result = new LegendItem(label, description, toolTipText, urlText,
                    getLegendShape(), fillPaint);
            result.setLabelFont(lookupLegendTextFont(series));
            Paint labelPaint = lookupLegendTextPaint(series);
            if (labelPaint != null) {
                result.setLabelPaint(labelPaint);
            }
            result.setSeriesKey(dataset.getSeriesKey(series));
            result.setSeriesIndex(series);
            result.setDataset(dataset);
            result.setDatasetIndex(datasetIndex);
        }

        return result;

    }

    /**
     * Tests this renderer for equality with an arbitrary object.  This method
     * returns {@code true} if and only if:
     *
     * <ul>
     * <li>{@code obj} is not {@code null};</li>
     * <li>{@code obj} is an instance of {@code XYDotRenderer};</li>
     * <li>both renderers have the same attribute values.
     * </ul>
     *
     * @param obj  the object ({@code null} permitted).
     *
     * @return A boolean.
     */
    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof XYDotRenderer)) {
            return false;
        }
        XYDotRenderer that = (XYDotRenderer) obj;
        if (this.dotWidth != that.dotWidth) {
            return false;
        }
        if (this.dotHeight != that.dotHeight) {
            return false;
        }
        if (!ShapeUtils.equal(this.legendShape, that.legendShape)) {
            return false;
        }
        return super.equals(obj);
    }

    /**
     * Returns a clone of the renderer.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException  if the renderer cannot be cloned.
     */
    @Override
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream)
            throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        this.legendShape = SerialUtils.readShape(stream);
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException  if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtils.writeShape(this.legendShape, stream);
    }

}