/* ===========================================================
 * 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.]
 *
 * --------------------------
 * CategoryLabelPosition.java
 * --------------------------
 * (C) Copyright 2003-2005, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * $Id: CategoryLabelPosition.java,v 1.7.2.1 2005/10/25 20:37:34 mungady Exp $
 *
 * Changes
 * -------
 * 31-Oct-2003 : Version 1 (DG);
 * 17-Feb-2004 : Added new constructor (DG);
 * 23-Mar-2004 : Added width calculation parameters (DG);
 * 07-Jan-2005 : Fixed bug in equals() method (DG);
 * 11-Jan-2005 : Removed deprecated constructor in preparation for the 1.0.0 
 *               release (DG);
 *
 */

package org.jfree.chart.axis;

import java.io.Serializable;

import org.jfree.text.TextBlockAnchor;
import org.jfree.ui.RectangleAnchor;
import org.jfree.ui.TextAnchor;

/**
 * The attributes that control the position of the labels for the categories on 
 * a {@link CategoryAxis}. Instances of this class are immutable and other 
 * JFreeChart classes rely upon this.
 */
public class CategoryLabelPosition implements Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 5168681143844183864L;
    
    /** The category anchor point. */
    private RectangleAnchor categoryAnchor;
    
    /** The text block anchor. */
    private TextBlockAnchor labelAnchor;
    
    /** The rotation anchor. */
    private TextAnchor rotationAnchor;

    /** The rotation angle (in radians). */    
    private double angle;
    
    /** The width calculation type. */
    private CategoryLabelWidthType widthType;
    
    /** 
     * The maximum label width as a percentage of the category space or the 
     * range space. 
     */
    private float widthRatio;
    
    /**
     * Creates a new position record with default settings.
     */
    public CategoryLabelPosition() {
        this(
            RectangleAnchor.CENTER, TextBlockAnchor.BOTTOM_CENTER, 
            TextAnchor.CENTER, 0.0, CategoryLabelWidthType.CATEGORY, 0.95f
        );
    }
    
    /**
     * Creates a new category label position record.
     * 
     * @param categoryAnchor  the category anchor (<code>null</code> not 
     *                        permitted).
     * @param labelAnchor  the label anchor (<code>null</code> not permitted).
     */
    public CategoryLabelPosition(RectangleAnchor categoryAnchor, 
                                 TextBlockAnchor labelAnchor) {
        // argument checking delegated...
        this(
            categoryAnchor, labelAnchor, TextAnchor.CENTER, 0.0, 
            CategoryLabelWidthType.CATEGORY, 0.95f
        );
    }
    
    /**
     * Creates a new category label position record.
     * 
     * @param categoryAnchor  the category anchor (<code>null</code> not 
     *                        permitted).
     * @param labelAnchor  the label anchor (<code>null</code> not permitted).
     * @param widthType  the width type (<code>null</code> not permitted).
     * @param widthRatio  the maximum label width as a percentage (of the 
     *                    category space or the range space).
     */
    public CategoryLabelPosition(RectangleAnchor categoryAnchor, 
                                 TextBlockAnchor labelAnchor,
                                 CategoryLabelWidthType widthType,
                                 float widthRatio) {
        // argument checking delegated...
        this(
            categoryAnchor, labelAnchor, TextAnchor.CENTER, 
            0.0, widthType, widthRatio
        );
    }
    
    /**
     * Creates a new position record.  The item label anchor is a point 
     * relative to the data item (dot, bar or other visual item) on a chart.  
     * The item label is aligned by aligning the text anchor with the item 
     * label anchor.
     * 
     * @param categoryAnchor  the category anchor (<code>null</code> not 
     *                        permitted).
     * @param labelAnchor  the label anchor (<code>null</code> not permitted).
     * @param rotationAnchor  the rotation anchor (<code>null</code> not 
     *                        permitted).
     * @param angle  the rotation angle (<code>null</code> not permitted).
     * @param widthType  the width type (<code>null</code> not permitted).
     * @param widthRatio  the maximum label width as a percentage (of the 
     *                    category space or the range space).
     */
    public CategoryLabelPosition(RectangleAnchor categoryAnchor, 
                                 TextBlockAnchor labelAnchor,
                                 TextAnchor rotationAnchor,
                                 double angle,
                                 CategoryLabelWidthType widthType,
                                 float widthRatio) {
        
        if (categoryAnchor == null) {
            throw new IllegalArgumentException(
                "Null 'categoryAnchor' argument."
            );
        }
        if (labelAnchor == null) {
            throw new IllegalArgumentException(
                "Null 'labelAnchor' argument."
            );
        }
        if (rotationAnchor == null) {
            throw new IllegalArgumentException(
                "Null 'rotationAnchor' argument."
            );
        }
        if (widthType == null) {
            throw new IllegalArgumentException("Null 'widthType' argument.");   
        }
        
        this.categoryAnchor = categoryAnchor;
        this.labelAnchor = labelAnchor;
        this.rotationAnchor = rotationAnchor;
        this.angle = angle;
        this.widthType = widthType;
        this.widthRatio = widthRatio;
    
    }
    
    /**
     * Returns the item label anchor.
     * 
     * @return The item label anchor (never <code>null</code>).
     */
    public RectangleAnchor getCategoryAnchor() {
        return this.categoryAnchor;
    }
    
    /**
     * Returns the text block anchor.
     * 
     * @return The text block anchor (never <code>null</code>).
     */
    public TextBlockAnchor getLabelAnchor() {
        return this.labelAnchor;
    }
    
    /**
     * Returns the rotation anchor point.
     * 
     * @return The rotation anchor point (never <code>null</code>).
     */
    public TextAnchor getRotationAnchor() {
        return this.rotationAnchor;
    }
    
    /**
     * Returns the angle of rotation for the label.
     * 
     * @return The angle (in radians).
     */
    public double getAngle() {
        return this.angle;
    }
    
    /**
     * Returns the width calculation type.
     * 
     * @return The width calculation type.
     */
    public CategoryLabelWidthType getWidthType() {
        return this.widthType;   
    }
    
    /**
     * Returns the ratio used to calculate the maximum category label width.
     * 
     * @return The ratio.
     */
    public float getWidthRatio() {
        return this.widthRatio;   
    }
    
    /**
     * Tests this instance for equality with an arbitrary object.
     * 
     * @param obj  the object (<code>null</code> permitted).
     * 
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof CategoryLabelPosition)) {
            return false;
        }
        CategoryLabelPosition that = (CategoryLabelPosition) obj;
        if (!this.categoryAnchor.equals(that.categoryAnchor)) {
            return false;
        }
        if (!this.labelAnchor.equals(that.labelAnchor)) {
            return false;
        }
        if (!this.rotationAnchor.equals(that.rotationAnchor)) {
            return false;
        }
        if (this.angle != that.angle) {
            return false;
        }
        if (this.widthType != that.widthType) {
            return false;
        }
        if (this.widthRatio != that.widthRatio) {
            return false;
        }
        return true;
    }
    
    /**
     * Returns a hash code for this object.
     * 
     * @return A hash code.
     */
    public int hashCode() {
        int result = 19;
        result = 37 * result + this.categoryAnchor.hashCode();
        result = 37 * result + this.labelAnchor.hashCode();
        result = 37 * result + this.rotationAnchor.hashCode();
        return result;
    }

}
