/* ===========================================================
 * 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., 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.]
 *
 * ---------------------------
 * CategoryTextAnnotation.java
 * ---------------------------
 * (C) Copyright 2003-2005, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * $Id: CategoryTextAnnotation.java,v 1.4 2005/02/28 16:11:12 mungady Exp $
 *
 * Changes:
 * --------
 * 02-Apr-2003 : Version 1 (DG);
 * 02-Jul-2003 : Added new text alignment and rotation options (DG);
 * 04-Jul-2003 : Added a category anchor option (DG);
 * 19-Aug-2003 : Added equals(...) method and implemented Cloneable (DG);
 * 21-Jan-2004 : Update for renamed method in ValueAxis (DG);
 * 30-Sep-2004 : Moved drawRotatedString() from RefineryUtilities 
 *               --> TextUtilities (DG);
 *
 */

package org.jfree.chart.annotations;

import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.axis.CategoryAnchor;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.Plot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.CategoryDataset;
import org.jfree.text.TextUtilities;
import org.jfree.ui.RectangleEdge;

/**
 * A text annotation that can be placed on a 
 * {@link org.jfree.chart.plot.CategoryPlot}.
 */
public class CategoryTextAnnotation extends TextAnnotation
                                    implements CategoryAnnotation, 
                                               Cloneable, Serializable {

    /** The category. */
    private Comparable category;

    /** The category anchor (START, MIDDLE, or END). */
    private CategoryAnchor categoryAnchor;
     
    /** The value. */
    private double value;

    /**
     * Creates a new annotation to be displayed at the given location.
     *
     * @param text  the text (<code>null</code> not permitted).
     * @param category  the category (<code>null</code> not permitted).
     * @param value  the value.
     */
    public CategoryTextAnnotation(String text, Comparable category, 
                                  double value) {
        super(text);
        if (category == null) {
            throw new IllegalArgumentException("Null 'category' argument.");   
        }
        this.category = category;
        this.value = value;
        this.categoryAnchor = CategoryAnchor.MIDDLE;
    }

    /**
     * Returns the category.
     * 
     * @return The category (never <code>null</code>).
     */
    public Comparable getCategory() {
        return this.category;
    }
    
    /**
     * Sets the category that the annotation attaches to.
     * 
     * @param category  the category (<code>null</code> not permitted).
     */
    public void setCategory(Comparable category) {
        if (category == null) {
            throw new IllegalArgumentException("Null 'category' argument.");   
        }
        this.category = category;
    }
    
    /**
     * Returns the category anchor point.
     * 
     * @return The category anchor point.
     */
    public CategoryAnchor getCategoryAnchor() {
        return this.categoryAnchor;
    }
    
    /**
     * Sets the category anchor point.
     * 
     * @param anchor  the anchor point (<code>null</code> not permitted).
     */
    public void setCategoryAnchor(CategoryAnchor anchor) {
        if (anchor == null) {
            throw new IllegalArgumentException("Null 'anchor' argument.");   
        }
        this.categoryAnchor = anchor;    
    }
    
    /**
     * Returns the value that the annotation attaches to.
     * 
     * @return The value.
     */
    public double getValue() {
        return this.value;
    }
    
    /**
     * Sets the value.
     * 
     * @param value  the value.
     */
    public void setValue(double value) {
        this.value = value;    
    }
    
    /**
     * Draws the annotation.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param dataArea  the data area.
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     */
    public void draw(Graphics2D g2, CategoryPlot plot, Rectangle2D dataArea,
                     CategoryAxis domainAxis, ValueAxis rangeAxis) {

        CategoryDataset dataset = plot.getDataset();
        int catIndex = dataset.getColumnIndex(this.category);
        int catCount = dataset.getColumnCount();

        float anchorX = 0.0f;
        float anchorY = 0.0f;
        PlotOrientation orientation = plot.getOrientation();
        RectangleEdge domainEdge = Plot.resolveDomainAxisLocation(
            plot.getDomainAxisLocation(), orientation
        );
        RectangleEdge rangeEdge = Plot.resolveRangeAxisLocation(
            plot.getRangeAxisLocation(), orientation
        );
        
        if (orientation == PlotOrientation.HORIZONTAL) {
            anchorY = (float) domainAxis.getCategoryJava2DCoordinate(
                this.categoryAnchor, catIndex, catCount, dataArea, domainEdge
            );
            anchorX = (float) rangeAxis.valueToJava2D(
                this.value, dataArea, rangeEdge
            );
        }
        else if (orientation == PlotOrientation.VERTICAL) {
            anchorX = (float) domainAxis.getCategoryJava2DCoordinate(
                this.categoryAnchor, catIndex, catCount, dataArea, domainEdge
            );
            anchorY = (float) rangeAxis.valueToJava2D(
                this.value, dataArea, rangeEdge
            );
        }
        g2.setFont(getFont());
        g2.setPaint(getPaint());
        TextUtilities.drawRotatedString(
            getText(), 
            g2,
            anchorX, 
            anchorY,
            getTextAnchor(),
            getRotationAngle(),
            getRotationAnchor()
        );

    }

    /**
     * Tests this object for equality with another.
     * 
     * @param obj  the object (<code>null</code> permitted).
     * 
     * @return <code>true</code> or <code>false</code>.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof CategoryTextAnnotation)) {
            return false;
        }
        CategoryTextAnnotation that = (CategoryTextAnnotation) obj;
        if (!super.equals(obj)) {
            return false;
        }
        if (!this.category.equals(that.getCategory())) {
            return false;
        }
        if (!this.categoryAnchor.equals(that.getCategoryAnchor())) {
            return false;
        }
        if (this.value != that.getValue()) {
            return false;    
        }
        return true;
    }
    
    /**
     * Returns a clone of the annotation.
     * 
     * @return A clone.
     * 
     * @throws CloneNotSupportedException  this class will not throw this 
     *         exception, but subclasses (if any) might.
     */
    public Object clone() throws CloneNotSupportedException {
        return super.clone();    
    }
    
}