/*
 *    This program 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 of the License, or
 *    (at your option) any later version.
 *
 *    This program 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 this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *    LayoutEngine.java
 *    Copyright (C) 2003 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.gui.graphvisualizer;

import weka.core.FastVector;
import javax.swing.JPanel;
import javax.swing.JProgressBar;

/**
 * This interface class has been added to facilitate the addition
 * of other layout engines to this package. Any class
 * that wants to lay out a graph should implement this
 * interface.
 *
 * @author Ashraf M. Kibriya (amk14@cs.waikato.ac.nz)
 * @version $Revision: 1.6 $ - 24 Apr 2003 - Initial version (Ashraf M. Kibriya)
 */
public interface LayoutEngine {
  /**
   * This method lays out the graph for better visualization
   */
  void layoutGraph();
  
  /**
   * This method sets the nodes and edges vectors of the LayoutEngine
   */
  void setNodesEdges(FastVector nodes, FastVector edges);
  /**
   * This method sets the allowed size of the node
   */
  void setNodeSize(int nodeWidth, int nodeHeight);
  
  /** give access to set of graph nodes */
   FastVector getNodes();

  /**
   * This method returns the extra controls panel
   * for the LayoutEngine, if there is any.
   */
  JPanel getControlPanel();
  
  /**
   * This method returns the progress bar
   * for the LayoutEngine, which shows
   * the progress of the layout process,
   * if it takes a while to layout the
   * graph
   */
  JProgressBar getProgressBar();
  
  /**
   * This method adds a LayoutCompleteEventListener to the
   * LayoutEngine.
   * @param e - The LayoutCompleteEventListener to add
   */
  void addLayoutCompleteEventListener(LayoutCompleteEventListener e);
  
  /**
   * This method removes a LayoutCompleteEventListener from the
   * LayoutEngine.
   * @param e - The LayoutCompleteEventListener to remove.
   */
  void removeLayoutCompleteEventListener(LayoutCompleteEventListener e);
  
  /**
   * This fires a LayoutCompleteEvent once a layout has been completed.
   */
  void fireLayoutCompleteEvent(LayoutCompleteEvent e);
}