/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

package ov;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

import javax.swing.JButton;
import javax.swing.JLabel;

import com.sun.star.accessibility.AccessibleEventId;
import com.sun.star.accessibility.AccessibleEventObject;
import com.sun.star.accessibility.AccessibleStateType;
import com.sun.star.accessibility.XAccessibleComponent;
import com.sun.star.accessibility.XAccessibleContext;
import com.sun.star.accessibility.XAccessibleStateSet;
import com.sun.star.uno.UnoRuntime;

public class FocusView
    extends ListeningObjectView
    implements ActionListener
{
    /** Create a FocusView when the given object supports the
        XAccessibleComponent interface.
    */
    public static ObjectView Create (
        ObjectViewContainer aContainer,
        XAccessibleContext xContext)
    {
        XAccessibleComponent xComponent = UnoRuntime.queryInterface(
                XAccessibleComponent.class, xContext);
        if (xComponent != null)
            return new FocusView (aContainer);
        else
            return null;
    }

    private FocusView (ObjectViewContainer aContainer)
    {
        super (aContainer);

        setLayout (new GridBagLayout());
        GridBagConstraints aConstraints = new GridBagConstraints ();

        maFocused = new JLabel ();
        aConstraints.gridy = 0;
        aConstraints.weightx = 1;
        aConstraints.fill = GridBagConstraints.HORIZONTAL;
        add (maFocused, aConstraints);

        maGrabFocus = new JButton ("grabFocus");
        aConstraints.gridy = 1;
        aConstraints.fill = GridBagConstraints.NONE;
        aConstraints.anchor = GridBagConstraints.WEST;
        add (maGrabFocus, aConstraints);

        maGrabFocus.addActionListener (this);
    }

    /** Additionally to the context store a reference to the
        XAccessibleComponent interface.
    */
    @Override
    public void SetObject (XAccessibleContext xObject)
    {
        mxComponent = UnoRuntime.queryInterface(
                XAccessibleComponent.class, xObject);
        super.SetObject (xObject);
    }

    @Override
    synchronized public void Destroy ()
    {
        super.Destroy();
        maGrabFocus.removeActionListener (this);
    }

    @Override
    synchronized public void Update ()
    {
        if (mxContext == null)
        {
            maFocused.setText ("<null object>");
            maGrabFocus.setEnabled (false);
        }
        else
        {
            XAccessibleStateSet aStateSet = mxContext.getAccessibleStateSet();
            if (aStateSet.contains(AccessibleStateType.FOCUSED))
                maFocused.setText ("focused");
            else
                maFocused.setText ("not focused");
            if (maGrabFocus != null)
                maGrabFocus.setEnabled (true);
        }
    }

    @Override
    public String GetTitle ()
    {
        return "Focus";
    }

    synchronized public void actionPerformed (ActionEvent aEvent)
    {
        if (aEvent.getActionCommand().equals("grabFocus"))
        {
            mxComponent.grabFocus();
        }
    }

    @Override
    public void notifyEvent (AccessibleEventObject aEvent)
    {
        System.out.println (aEvent);
        if (aEvent.EventId == AccessibleEventId.STATE_CHANGED)
            Update ();
    }

    private final JLabel maFocused;
    private final JButton maGrabFocus;
    private XAccessibleComponent mxComponent;
}
