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

 * 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.]

 *

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

 * ImageTitle.java

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

 * (C) Copyright 2000-2004, by David Berry and Contributors;

 *

 * Original Author:  David Berry;

 * Contributor(s):   David Gilbert (for Object Refinery Limited);

 *

 * $Id: ImageTitle.java,v 1.1 2004/08/31 14:52:48 mungady Exp $

 *

 * Changes (from 18-Sep-2001)

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

 * 18-Sep-2001 : Added standard header (DG);

 * 07-Nov-2001 : Separated the JCommon Class Library classes, JFreeChart now requires

 *               jcommon.jar (DG);

 * 09-Jan-2002 : Updated Javadoc comments (DG);

 * 07-Feb-2002 : Changed blank space around title from Insets --> Spacer, to allow for relative

 *               or absolute spacing (DG);

 * 25-Jun-2002 : Updated import statements (DG);

 * 23-Sep-2002 : Fixed errors reported by Checkstyle (DG);

 * 26-Nov-2002 : Added method for drawing images at left or right (DG);

 * 22-Sep-2003 : Added checks that the Image can never be null (TM).

 */



package org.jfree.chart.title;



import java.awt.Graphics2D;

import java.awt.Image;

import java.awt.geom.Rectangle2D;



import org.jfree.chart.event.TitleChangeEvent;

import org.jfree.ui.HorizontalAlignment;

import org.jfree.ui.RectangleEdge;

import org.jfree.ui.Size2D;

import org.jfree.ui.Spacer;

import org.jfree.ui.VerticalAlignment;



/**

 * A chart title that displays an image.  This is useful, for example, if you

 * have an image of your corporate logo and want to use as a footnote or part

 * of a title in a chart you create.

 * <P>

 * ImageTitle needs an image passed to it in the constructor.  For ImageTitle

 * to work, you must have already loaded this image from its source (disk or

 * URL).  It is recomended you use something like

 * Toolkit.getDefaultToolkit().getImage() to get the image.  Then, use

 * MediaTracker or some other message to make sure the image is fully loaded

 * from disk.

 *

 * @author David Berry

 */

public class ImageTitle extends Title {



    /** The title image. */

    private Image image;



    /** The height used to draw the image (may involve scaling). */

    private int height;



    /** The width used to draw the image (may involve scaling). */

    private int width;



    /**

     * Creates a new image title.

     *

     * @param image  the image.

     */

    public ImageTitle(Image image) {



        this(image,

             image.getHeight(null),

             image.getWidth(null),

             Title.DEFAULT_POSITION,

             Title.DEFAULT_HORIZONTAL_ALIGNMENT,

             Title.DEFAULT_VERTICAL_ALIGNMENT,

             Title.DEFAULT_SPACER);



    }



    /**

     * Creates a new image title.

     *

     * @param image  the image.

     * @param position  the title position.

     * @param horizontalAlignment  the horizontal alignment.

     * @param verticalAlignment  the vertical alignment.

     */

    public ImageTitle(Image image, RectangleEdge position, 

                      HorizontalAlignment horizontalAlignment, 

                      VerticalAlignment verticalAlignment) {



        this(image,

             image.getHeight(null),

             image.getWidth(null),

             position,

             horizontalAlignment,

             verticalAlignment,

             Title.DEFAULT_SPACER);



    }



    /**

     * Creates a new image title with the given image scaled to the given

     * width and height in the given location.

     *

     * @param image  the image (not null).

     * @param height  the height used to draw the image.

     * @param width  the width used to draw the image.

     * @param position  the title position.

     * @param horizontalAlignment  the horizontal alignment.

     * @param verticalAlignment  the vertical alignment.

     * @param spacer  the amount of space to leave around the outside of the title.

     */

    public ImageTitle(Image image, int height, int width, RectangleEdge position,

                      HorizontalAlignment horizontalAlignment, VerticalAlignment verticalAlignment,

                      Spacer spacer) {



        super(position, horizontalAlignment, verticalAlignment, spacer);

        if (image == null) {

            throw new NullPointerException("ImageTitle(..): Image argument is null.");

        }

        this.image = image;

        this.height = height;

        this.width = width;



    }



    /**

     * Returns the image for the title.

     *

     * @return the image for the title.

     */

    public Image getImage() {

        return this.image;

    }



    /**

     * Sets the image for the title and notifies registered listeners that the

     * title has been modified.

     *

     * @param image  the new image (<code>null</code> not permitted).

     */

    public void setImage(Image image) {



        if (image == null) {

            throw new NullPointerException("ImageTitle.setImage (..): Image must not be null.");

        }

        this.image = image;

        notifyListeners(new TitleChangeEvent(this));



    }



    /**

     * Draws the title on a Java 2D graphics device (such as the screen or a printer).

     *

     * @param g2  the graphics device.

     * @param titleArea  the area within which the title (and plot) should be drawn.

     */

    public void draw(Graphics2D g2, Rectangle2D titleArea) {



        RectangleEdge position = getPosition();

        if (position == RectangleEdge.TOP || position == RectangleEdge.BOTTOM) {

            drawHorizontal(g2, titleArea);

        }

        else if (position == RectangleEdge.LEFT || position == RectangleEdge.RIGHT) {

            drawVertical(g2, titleArea);

        }

        else {

            throw new RuntimeException("ImageTitle.draw(...) - invalid title position.");

        }

    }



    /**

     * Returns the preferred width of the title.

     *

     * @param g2  the graphics device.

     * @param height  the height (ignored).

     *

     * @return the preferred width of the title.

     */

    public float getPreferredWidth(Graphics2D g2, float height) {

        Spacer spacer = getSpacer();

        float result = (float) spacer.getAdjustedWidth(this.width);

        return result;



    }



    /**

     * Returns the preferred height of the title.

     *

     * @param g2  the graphics device.

     * @param width  the width (ignored).

     *

     * @return the preferred height of the title.

     */

    public float getPreferredHeight(Graphics2D g2, float width) {

        Spacer spacer = getSpacer();

        float result = (float) spacer.getAdjustedHeight(this.height);

        return result;

    }



    /**

     * Draws the title on a Java 2D graphics device (such as the screen or a printer).

     *

     * @param g2  the graphics device.

     * @param chartArea  the area within which the title (and plot) should be drawn.

     *

     * @return the area used by the title.

     */

    protected Size2D drawHorizontal(Graphics2D g2, Rectangle2D chartArea) {



        double startY = 0.0;

        double topSpace = 0.0;

        double bottomSpace = 0.0;

        double leftSpace = 0.0;

        double rightSpace = 0.0;



        Spacer spacer = getSpacer();

        topSpace = spacer.getTopSpace(this.height);

        bottomSpace = spacer.getBottomSpace(this.height);

        leftSpace = spacer.getLeftSpace(this.width);

        rightSpace = spacer.getRightSpace(this.width);



        if (getPosition() == RectangleEdge.TOP) {

            startY = chartArea.getY() + topSpace;

        }

        else {

            startY = chartArea.getY() + chartArea.getHeight() - bottomSpace - this.height;

        }



        // what is our alignment?

        HorizontalAlignment horizontalAlignment = getHorizontalAlignment();

        double startX = 0.0;

        if (horizontalAlignment == HorizontalAlignment.CENTER) {

            startX = chartArea.getX() + leftSpace + chartArea.getWidth() / 2 - this.width / 2;

        }

        else if (horizontalAlignment == HorizontalAlignment.LEFT) {

            startX = chartArea.getX() + leftSpace;

        }

        else if (horizontalAlignment == HorizontalAlignment.RIGHT) {

            startX = chartArea.getX() + chartArea.getWidth() - rightSpace - this.width;

        }



        g2.drawImage(this.image, (int) startX, (int) startY, this.width, this.height, null);



        return new Size2D(chartArea.getWidth() + leftSpace + rightSpace,

            this.height + topSpace + bottomSpace);



    }



    /**

     * Draws the title on a Java 2D graphics device (such as the screen or a printer).

     *

     * @param g2  the graphics device.

     * @param chartArea  the area within which the title (and plot) should be drawn.

     *

     * @return the area used by the title.

     */

    protected Size2D drawVertical(Graphics2D g2, Rectangle2D chartArea) {



        double startX = 0.0;

        double topSpace = 0.0;

        double bottomSpace = 0.0;

        double leftSpace = 0.0;

        double rightSpace = 0.0;



        Spacer spacer = getSpacer();

        if (spacer != null) {

            topSpace = spacer.getTopSpace(this.height);

            bottomSpace = spacer.getBottomSpace(this.height);

            leftSpace = spacer.getLeftSpace(this.width);

            rightSpace = spacer.getRightSpace(this.width);

        }



        if (getPosition() == RectangleEdge.LEFT) {

            startX = chartArea.getX() + leftSpace;

        }

        else {

            startX = chartArea.getMaxX() - rightSpace - this.width;

        }



        // what is our alignment?

        VerticalAlignment alignment = getVerticalAlignment();

        double startY = 0.0;

        if (alignment == VerticalAlignment.CENTER) {

            startY = chartArea.getMinY() + topSpace + chartArea.getHeight() / 2 - this.height / 2;

        }

        else if (alignment == VerticalAlignment.TOP) {

            startY = chartArea.getMinY() + topSpace;

        }

        else if (alignment == VerticalAlignment.BOTTOM) {

            startY = chartArea.getMaxY() - bottomSpace - this.height;

        }



        g2.drawImage(this.image, (int) startX, (int) startY, this.width, this.height, null);



        return new Size2D(chartArea.getWidth() + leftSpace + rightSpace,

            this.height + topSpace + bottomSpace);



    }



}

