/*
 *  AChart2DAction, base for actions to trigger on charts.
 *  Copyright (C) 2007 - 2011 Achim Westermann, created on 10.12.2004, 13:48:55
 *
 *  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 St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *  If you modify or optimize the code in a useful way please let me know.
 *  Achim.Westermann@gmx.de
 *
 */

package info.monitorenter.gui.chart.events;

import info.monitorenter.gui.chart.Chart2D;
import info.monitorenter.gui.chart.IAxis;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

/**
 * The base class that connects triggered actions with an
 * {@link info.monitorenter.gui.chart.axis.AAxis} instance.
 * 

 * Every subclass may access it's constructor-given Axis instance
 * as protected member m_axis.
 * 

 * Note that this action only works for the first bottom x axis / first left y
 * axis: Additional axes cannot be handled by now.
 * 

 * 
 * @author Achim Westermann 
 * 
 * @version $Revision: 1.11 $
 * 
 */
public abstract class AAxisAction extends AChart2DAction implements PropertyChangeListener {

  /** Generated serialVersionUID. **/
  private static final long serialVersionUID = 2602716712958711393L;

  /** The target of this action. */
  private int m_axis;

  /**
   * Create an Action that accesses the chart's axis by argument
   * axis and identifies itself with the given action String.
   * 

   * 
   * @param chart
   *          the owner of the axis to trigger actions upon.
   * 
   * @param axis
   *          needed to identify the axis of the chart: one of {@link Chart2D#X}
   *          , {@link Chart2D#Y}.
   * 
   * @param description
   *          the descriptive String that will be displayed by
   *          {@link javax.swing.AbstractButton} subclasses that get this
   *          Action assigned (
   *          {@link javax.swing.AbstractButton#setAction(javax.swing.Action)}).
   * 
   */
  public AAxisAction(final Chart2D chart, final String description, final int axis) {

    super(chart, description);
    this.m_axis = axis;
    IAxis myAxis = this.getAxis();
    if (this.m_axis == Chart2D.X) {
      myAxis.addPropertyChangeListener(Chart2D.PROPERTY_AXIS_X_BOTTOM_REPLACE, this);
    } else if (this.m_axis == Chart2D.Y) {
      myAxis.addPropertyChangeListener(Chart2D.PROPERTY_AXIS_Y_LEFT_REPLACE, this);
    }
  }

  /**
   * Returns the axis that is controlled.
   * 

   * Note that several calls may return different instances (
   * a.getAxis() == a.getAxis() may be false) in case the
   * corresponding chart of the former axis gets a new axis assigned.
   * 

   * Note that this action only works for the first x axis / first y axis:
   * Additional axes cannot be handled by now.
   * 

   * 
   * @return the axis that is controlled.
   */
  protected IAxis getAxis() {

    // update in case the corresponding chart has a new axis:
    IAxis axis = null;
    switch (this.m_axis) {
      case Chart2D.X:
        axis = this.m_chart.getAxisX();
        break;
      case Chart2D.Y:
        axis = this.m_chart.getAxisY();
        break;
      default:
        break;
    }
    return axis;
  }

  /**
   * @see java.beans.PropertyChangeListener#propertyChange(java.beans.PropertyChangeEvent)
   */
  public void propertyChange(PropertyChangeEvent evt) {
    String property = evt.getPropertyName();
    if (((property.equals(Chart2D.PROPERTY_AXIS_X_BOTTOM_REPLACE)) && (this.m_axis == Chart2D.X))
        || (property.equals(Chart2D.PROPERTY_AXIS_Y_LEFT_REPLACE) && this.m_axis == Chart2D.Y)) {
      IAxis oldAxis = (IAxis) evt.getOldValue();
      IAxis newAxis = (IAxis) evt.getNewValue();
      if (property.equals(Chart2D.PROPERTY_AXIS_X_BOTTOM_REPLACE)) {
        oldAxis.removePropertyChangeListener(Chart2D.PROPERTY_AXIS_X_BOTTOM_REPLACE, this);
        newAxis.addPropertyChangeListener(Chart2D.PROPERTY_AXIS_X_BOTTOM_REPLACE, this);
      } else if (property.equals(Chart2D.PROPERTY_AXIS_Y_LEFT_REPLACE)) {
        oldAxis.removePropertyChangeListener(Chart2D.PROPERTY_AXIS_Y_LEFT_REPLACE, this);
        newAxis.addPropertyChangeListener(Chart2D.PROPERTY_AXIS_Y_LEFT_REPLACE, this);
      }
    }
  }
}