/*
 This file is part of the software framework JStatCom, 
 a library for building applications for data based analysis.

 Copyright (C) 2000-2005  Markus Kraetzig

 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
 */

package com.jstatcom.equation;

import java.awt.Component;
import java.awt.Container;
import java.awt.event.ContainerAdapter;
import java.awt.event.ContainerEvent;

import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

/**
 * Panel to be used as the container for all EqTerm components. It manages
 * the setting/unsetting of the leading signs and keeps track of the correct
 * reference point. It uses the EqLayout to display potentially
 * large equations.
 *
 * @author Alexander Benkwitz, Markus Kraetzig
 */
public final class EqPanel extends JPanel {
	/**
	 * Constructor.
	 */
	public EqPanel() {
		super(new EqLayout());
		setBorder(new EmptyBorder(0, 5, 0, 5));
		addContainerListener(new ContainerAdapter() {
			public void componentAdded(ContainerEvent evt) {

				if (evt.getChild() instanceof EqTermLHS) {
					if (getLayout() instanceof EqLayout)
						 ((EqLayout) getLayout()).numberLHS++;
				}
			}
		});
	}

	/**
	 * Delegates setEnabled to all childs of this container.
	 * 
	 * @param c java.awt.Component[]
	 * @param enabled boolean
	 */
	private void enableComponentsAndChilds(Component[] c, boolean enabled) {
		if (c != null) {
			for (int i = 0; i < c.length; i++) {
				c[i].setEnabled(enabled);
				if (c[i] instanceof Container) {
					enableComponentsAndChilds(
						((Container) c[i]).getComponents(),
						enabled);
				}
			}
		}
	}

	/**
	 * Overwrites supermethod to delegate the call to 
	 * all childs.
	 *
	 * @param enabled true if enabled
	 */
	public void setEnabled(boolean enabled) {
		enableComponentsAndChilds(getComponents(), enabled);
		super.setEnabled(enabled);
	}
}