/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2000 Intersect Software Corporation

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, see http://www.gnu.org
*/

package net.wotonomy.ui.swing.components;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.Rectangle;

import javax.swing.JPanel;
import javax.swing.JRootPane;

/**
 * A custom layout for a JRootPane that handles the the layout of a JRootPane's
 * layeredPane, glassPane, and menuBar, and in addition handles four decorative
 * components arranged in a border layout. Add the decorative components to the
 * JRootPane using the directional constants; CENTER is reserved for the content
 * pane and menu bar.
 *
 * @author michael@mpowers.net
 * @version $Revision: 904 $
 */
public class BetterRootLayout extends BorderLayout {
	/**
	 * Returns the amount of space the layout would like to have.
	 *
	 * @param the Container for which this layout manager is being used
	 * @return a Dimension object containing the layout's preferred size
	 * @throws ClassCastException if parent is not a JRootPane
	 */
	public Dimension preferredLayoutSize(Container parent) {
		JRootPane rootPane = (JRootPane) parent;

		JPanel proxyPanel = new JPanel();
		proxyPanel.setLayout(new BorderLayout());

		JPanel contentProxy = null;
		if (rootPane.getContentPane() != null) {
			contentProxy = new JPanel();
			contentProxy.setMinimumSize(rootPane.getContentPane().getMinimumSize());
			contentProxy.setMaximumSize(rootPane.getContentPane().getMaximumSize());
			contentProxy.setPreferredSize(rootPane.getContentPane().getPreferredSize());
			proxyPanel.add(contentProxy, CENTER);
		}
		JPanel menuProxy = null;
		if (rootPane.getJMenuBar() != null) {
			menuProxy = new JPanel();
			menuProxy.setMinimumSize(rootPane.getJMenuBar().getMinimumSize());
			menuProxy.setMaximumSize(rootPane.getJMenuBar().getMaximumSize());
			menuProxy.setPreferredSize(rootPane.getJMenuBar().getPreferredSize());
			proxyPanel.add(menuProxy, NORTH);
		}

		this.addLayoutComponent(proxyPanel, CENTER);

		Dimension result = super.preferredLayoutSize(parent);

		this.removeLayoutComponent(proxyPanel);

		proxyPanel.removeAll();

		return result;
	}

	/**
	 * Returns the minimum amount of space the layout needs.
	 *
	 * @param the Container for which this layout manager is being used
	 * @return a Dimension object containing the layout's minimum size
	 * @throws ClassCastException if parent is not a JRootPane
	 */
	public Dimension minimumLayoutSize(Container parent) {
		JRootPane rootPane = (JRootPane) parent;

		JPanel proxyPanel = new JPanel();
		proxyPanel.setLayout(new BorderLayout());

		JPanel contentProxy = null;
		if (rootPane.getContentPane() != null) {
			contentProxy = new JPanel();
			contentProxy.setMinimumSize(rootPane.getContentPane().getMinimumSize());
			contentProxy.setMaximumSize(rootPane.getContentPane().getMaximumSize());
			contentProxy.setPreferredSize(rootPane.getContentPane().getPreferredSize());
			proxyPanel.add(contentProxy, CENTER);
		}
		JPanel menuProxy = null;
		if (rootPane.getJMenuBar() != null) {
			menuProxy = new JPanel();
			menuProxy.setMinimumSize(rootPane.getJMenuBar().getMinimumSize());
			menuProxy.setMaximumSize(rootPane.getJMenuBar().getMaximumSize());
			menuProxy.setPreferredSize(rootPane.getJMenuBar().getPreferredSize());
			proxyPanel.add(menuProxy, NORTH);
		}

		this.addLayoutComponent(proxyPanel, CENTER);

		Dimension result = super.minimumLayoutSize(parent);

		this.removeLayoutComponent(proxyPanel);

		proxyPanel.removeAll();

		return result;
	}

	/**
	 * Returns the maximum amount of space the layout can use.
	 *
	 * @param the Container for which this layout manager is being used
	 * @return a Dimension object containing the layout's maximum size
	 * @throws ClassCastException if parent is not a JRootPane
	 */
	public Dimension maximumLayoutSize(Container target) {
		JRootPane rootPane = (JRootPane) target;

		JPanel proxyPanel = new JPanel();
		proxyPanel.setLayout(new BorderLayout());

		JPanel contentProxy = null;
		if (rootPane.getContentPane() != null) {
			contentProxy = new JPanel();
			contentProxy.setMinimumSize(rootPane.getContentPane().getMinimumSize());
			contentProxy.setMaximumSize(rootPane.getContentPane().getMaximumSize());
			contentProxy.setPreferredSize(rootPane.getContentPane().getPreferredSize());
			proxyPanel.add(contentProxy, CENTER);
		}
		JPanel menuProxy = null;
		if (rootPane.getJMenuBar() != null) {
			menuProxy = new JPanel();
			menuProxy.setMinimumSize(rootPane.getJMenuBar().getMinimumSize());
			menuProxy.setMaximumSize(rootPane.getJMenuBar().getMaximumSize());
			menuProxy.setPreferredSize(rootPane.getJMenuBar().getPreferredSize());
			proxyPanel.add(menuProxy, NORTH);
		}

		this.addLayoutComponent(proxyPanel, CENTER);

		Dimension result = super.maximumLayoutSize(target);

		this.removeLayoutComponent(proxyPanel);

		proxyPanel.removeAll();

		return result;
	}

	/**
	 * Instructs the layout manager to perform the layout for the specified
	 * container.
	 *
	 * @param the Container for which this layout manager is being used
	 * @throws ClassCastException if parent is not a JRootPane
	 */
	public void layoutContainer(Container parent) {
		JRootPane rootPane = (JRootPane) parent;

		Rectangle b = parent.getBounds();
		Insets i = rootPane.getInsets();
		int w = b.width - i.right - i.left;
		int h = b.height - i.top - i.bottom;

		// layout panes

		if (rootPane.getLayeredPane() != null) {
			rootPane.getLayeredPane().setBounds(i.left, i.top, w, h);
		}
		if (rootPane.getGlassPane() != null) {
			rootPane.getGlassPane().setBounds(i.left, i.top, w, h);
		}

		// handle proxy panel

		JPanel proxyPanel = new JPanel();
		proxyPanel.setLayout(new BorderLayout());

		this.addLayoutComponent(proxyPanel, CENTER);

		super.layoutContainer(parent);

		// use proxy sizes to set sizes of layeredPane's children

		Rectangle proxyRect = proxyPanel.getBounds();
		if (rootPane.getJMenuBar() != null) {
			Rectangle menuRect = proxyPanel.getBounds();
			menuRect.height = rootPane.getJMenuBar().getPreferredSize().height;
			rootPane.getJMenuBar().setBounds(menuRect);
			proxyRect.y += menuRect.height;
			proxyRect.height -= menuRect.height;
		}
		if (rootPane.getContentPane() != null) {
			rootPane.getContentPane().setBounds(proxyRect);
		}

		this.removeLayoutComponent(proxyPanel);

		proxyPanel.removeAll();
	}

	/**
	 * Passes NORTH, SOUTH, EAST, WEST and CENTER to super implementation, and
	 * ignores all others.
	 */
	public void addLayoutComponent(Component comp, Object constraints) {
		if (NORTH.equals(constraints)) {
			super.addLayoutComponent(comp, constraints);
		} else if (SOUTH.equals(constraints)) {
			super.addLayoutComponent(comp, constraints);
		} else if (EAST.equals(constraints)) {
			super.addLayoutComponent(comp, constraints);
		} else if (WEST.equals(constraints)) {
			super.addLayoutComponent(comp, constraints);
		} else if (CENTER.equals(constraints)) {
			super.addLayoutComponent(comp, constraints);
		}

		// otherwise, ignore
	}
}