/* GraphicAttribute.java
   Copyright (C) 2003 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */


package java.awt.font;

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

/**
 * This class represents a graphic embedded in text.
 * 
 * @author Michael Koch
 * @author Lillian Angel (langel at redhat dot com)
 */
public abstract class GraphicAttribute
{
  public static final int BOTTOM_ALIGNMENT = - 2;
  public static final int CENTER_BASELINE = 1;
  public static final int HANGING_BASELINE = 2;
  public static final int ROMAN_BASELINE = 0;
  public static final int TOP_ALIGNMENT = - 1;

  private int alignment;

  /**
   * Constructor.
   * 
   * @param alignment - the alignment to use for the graphic
   */
  protected GraphicAttribute(int alignment)
  {
    if (alignment < BOTTOM_ALIGNMENT || alignment > HANGING_BASELINE)
      throw new IllegalArgumentException("Invalid alignment");
    this.alignment = alignment;
  }

  /**
   * Draws the graphic.
   * 
   * @param graphics - the graphics configuration to use
   * @param x - the x location
   * @param y - the y location
   */
  public abstract void draw(Graphics2D graphics, float x, float y);

  /**
   * Gets the distance from the origin of its graphic to the right side of the
   * bounds of its graphic.
   * 
   * @return the advance
   */
  public abstract float getAdvance();

  /**
   * Gets the positive distance from the origin of its graphic to the top of
   * bounds.
   * 
   * @return the ascent
   */
  public abstract float getAscent();

  /**
   * Gets the distance from the origin of its graphic to the bottom of the bounds.
   * 
   * @return the descent
   */
  public abstract float getDescent();

  /**
   * Gets the alignment.
   * 
   * @return the alignment
   */
  public final int getAlignment()
  {
    return alignment;
  }

  /**
   * Returns a Rectangle2D that encloses the rendered area.
   * Default bounds is the rectangle (0, -ascent, advance, ascent+descent).
   * 
   * @return the bounds of the rendered area
   */
  public Rectangle2D getBounds()
  {
    float asc = getAscent();
    return new Rectangle2D.Float(0, - asc, getAdvance(), asc + getDescent());
  }

  /**
   * Returns the justification information for this object.
   * 
   * @return the justification information
   */
  public GlyphJustificationInfo getJustificationInfo()
  {
    float adv = getAdvance();
    return new GlyphJustificationInfo(adv, false, 2, adv / 3, adv / 3, false,
                                      1, 0, 0);
  }
}