/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.

 */

package com.oracle.solaris.vp.panel.swing.view;

import java.awt.EventQueue;

import java.awt.event.*;

import java.util.*;

import javax.swing.*;

import com.oracle.solaris.vp.panel.common.control.*;

import com.oracle.solaris.vp.util.misc.*;

import com.oracle.solaris.vp.util.misc.finder.*;

import com.oracle.solaris.vp.util.swing.*;

import com.oracle.solaris.vp.util.swing.layout.*;

@SuppressWarnings({"serial"})

public class NavButtonPanel extends JPanel {

    //

    // Static data

    //

    private static final Icon ICON_BACK;

    private static final Icon ICON_FORWARD;

    static {

	int height = GUIUtil.getButtonIconHeight();

	Icon icon = GnomeUtil.getIcon("back", height, true);

	if (icon == null) {

	    icon = Finder.getIcon("images/navigation/back.png");

	}

	ICON_BACK = icon;

	icon = GnomeUtil.getIcon("forward", height, true);

	if (icon == null) {

	    icon = Finder.getIcon("images/navigation/forward.png");

	}

	ICON_FORWARD = icon;

    }

    private static final String TOOLTIP_BACK =

	Finder.getString("navigation.back.long");

    private static final String TOOLTIP_FORWARD =

	Finder.getString("navigation.forward.long");

    //

    // Instance data

    //

    private Navigator navigator;

    private JButton backButton;

    private JButton forwardButton;

    private NavigationListener navListener =

	new NavigationListener() {

	    @Override

	    public void navigationStarted(NavigationStartEvent e) {

	    }

	    @Override

	    public void navigationStopped(NavigationStopEvent e) {

		addCurrentToHistory(e.getSource());

	    }

	};

    private HistoryList<List<Navigable>> history =

	new HistoryList<List<Navigable>>();

    private boolean goingBack;

    //

    // Constructors

    //

    public NavButtonPanel() {

	createNavButtons();

	setLayout(new RowLayout(HorizontalAnchor.FILL));

	int gap = GUIUtil.getHalfGap();

	RowLayoutConstraint r =

	    new RowLayoutConstraint(VerticalAnchor.CENTER);

	add(backButton, r);

	add(forwardButton, r);

    }

    public NavButtonPanel(Navigator navigator) {

	this();

	setNavigator(navigator);

    }

    //

    // NavButtonPanel methods

    //

    public JButton getBackButton() {

	return backButton;

    }

    public JButton getForwardButton() {

	return forwardButton;

    }

    public Navigator getNavigator() {

	return navigator;

    }

    /**

     * Navigates backward through the navigation history.

     *

     * @exception   NoSuchElementException

     *		    if there is no previous entry in the history

     */

    public void goBack() {

	List<Navigable> target = history.peekOrErr(1);

	goingBack = true;

	try {

	    Navigable[] path = target.toArray(new Navigable[target.size()]);

	    navigator.goTo(false, null, path);

	} catch (NavigationException ignore) {

	} finally {

	    goingBack = false;

	}

    }

    /**

     * Navigates forward through the navigation history.

     *

     * @exception   NoSuchElementException

     *		    if there is no following entry in the history

     */

    public void goForward() {

	List<Navigable> target = history.peekForward();

	try {

	    Navigable[] path = target.toArray(new Navigable[target.size()]);

	    navigator.goTo(false, null, path);

	} catch (NavigationException ignore) {

	}

    }

    public void setNavigator(Navigator navigator) {

	Navigator oldNav = getNavigator();

	if (!ObjectUtil.equals(oldNav, navigator)) {

	    if (oldNav != null) {

		oldNav.removeNavigationListener(navListener);

	    }

	    if (navigator != null) {

		navigator.addNavigationListener(navListener);

	    }

	    this.navigator = navigator;

	}

    }

    //

    // Private methods

    //

    private void addCurrentToHistory(Navigator navigator) {

	List<Control> path = navigator.getPath();

	if (!isCurrent(path)) {

	    boolean addPath = true;

	    if (goingBack) {

		try {

		    history.goBack();

		    if (isCurrent(path)) {

			addPath = false;

		    }

		} catch (NoSuchElementException ignore) {

		}

	    }

	    if (addPath) {

		List<Navigable> savedPath =

		    new ArrayList<Navigable>(path.size());

		for (int i = 0, n = path.size(); i < n; i++) {

		    Control control = path.get(i);

		    // First element of Navigable array must be a Control -- see

		    // Navigator.goTo

		    Navigable navigable = i == 0 ? control :

			new SimpleNavigable(control.getId(), control.getName(),

			control.getParameters());

		    savedPath.add(navigable);

		}

		if (isNext(path)) {

		    history.goForward();

		} else {

		    history.push(savedPath);

		}

	    }

	    EventQueue.invokeLater(

		new Runnable() {

		    @Override

		    public void run() {

			setButtonsEnabledState();

		    }

		});

	}

    }

    private void createNavButtons() {

	backButton = new JButton(ICON_BACK);

	backButton.setToolTipText(TOOLTIP_BACK);

	backButton.addActionListener(

	    new ActionListener() {

		@Override

		public void actionPerformed(ActionEvent e) {

		    // Launch navigation on non-event thread

		    navigator.asyncExec(

			new Runnable() {

			    @Override

			    public void run() {

				goBack();

			    }

			});

		}

	    });

        int bMargin = GUIUtil.getToolBarButtonMargin();

	GUIUtil.setHorizontalMargin(backButton, bMargin);

	new RolloverHandler(backButton);

	forwardButton = new JButton(ICON_FORWARD);

	forwardButton.setToolTipText(TOOLTIP_FORWARD);

	forwardButton.addActionListener(

	    new ActionListener() {

		@Override

		public void actionPerformed(ActionEvent e) {

		    // Launch navigation on non-event thread

		    navigator.asyncExec(

			new Runnable() {

			    @Override

			    public void run() {

				goForward();

			    }

			});

		}

	    });

	GUIUtil.setHorizontalMargin(forwardButton, bMargin);

	new RolloverHandler(forwardButton);

	setButtonsEnabledState();

    }

    private boolean equals(List<? extends Navigable> pathA,

	List<? extends Navigable> pathB) {

	boolean retVal = false;

	if (pathA.size() == pathB.size()) {

	    retVal = true;

	    for (int i = 0, n = pathA.size(); i < n; i++) {

		if (!Navigable.Util.equals(pathA.get(i), pathB.get(i))) {

		    retVal = false;

		    break;

		}

	    }

	}

	return retVal;

    }

    private boolean isCurrent(List<? extends Navigable> path) {

	try {

	    return equals(path, history.peekOrErr());

	} catch (NoSuchElementException e) {

	    return false;

	}

    }

    private boolean isNext(List<? extends Navigable> path) {

	try {

	    return equals(path, history.peekForward());

	} catch (NoSuchElementException e) {

	    return false;

	}

    }

    private void setButtonsEnabledState() {

	backButton.setEnabled(history.getPointer() > 1);

	forwardButton.setEnabled(history.getPointer() !=

	    history.getFullCount());

    }

}