/* ----------------------------------------------------------------------------
   The Kiwi Toolkit - A Java Class Library
   Copyright (C) 1998-2004 Mark A. Lindner

   This library 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 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
   General Public License for more details.

   You should have received a copy of the GNU 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.
 
   The author may be contacted at: mark_a_lindner@yahoo.com
   ----------------------------------------------------------------------------
   $Log: AboutFrame.java,v $
   Revision 1.10  2004/05/12 19:03:13  markl
   comment block updates

   Revision 1.9  2004/03/16 06:43:39  markl
   LocaleManager method change

   Revision 1.8  2003/01/19 09:48:26  markl
   Replaced instances of JScrollPane with KScrollPane.

   Revision 1.7  2001/06/26 06:15:27  markl
   Added buildContentPanel().

   Revision 1.6  2001/03/12 09:27:51  markl
   Source code and Javadoc cleanup.

   Revision 1.5  1999/11/19 06:05:13  markl
   Fixed a NullPointerException.

   Revision 1.4  1999/10/05 02:48:47  markl
   Made Home button optional.

   Revision 1.3  1999/06/28 09:37:06  markl
   I18N.

   Revision 1.2  1999/01/10 01:00:58  markl
   added GPL header & RCS tag
   ----------------------------------------------------------------------------
*/

package kiwi.ui;

import java.awt.*;
import java.awt.event.*;
import java.net.URL;
import java.io.IOException;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import javax.swing.event.*;
import javax.swing.text.Document;
import javax.swing.text.html.HTMLEditorKit;

import kiwi.util.*;

/** An "About..." style window. The window displays an HTML document in a
  * scroll pane and provides <i>Home</i> and <i>Close</i> buttons. This
  * component is hyperlink sensitive and will follow links embedded in the
  * documents it displays. Clicking the optional <i>Home</i> button causes the
  * component to redisplay the initial document.
  * <p>
  * URLs may point to resources on the network or to system resources loaded
  * using a <code>ResourceManager</code> or <code>ResourceLoader</code>.
  *
  * <p><center>
  * <img src="snapshot/AboutFrame.gif"><br>
  * <i>An example AboutFrame.</i>
  * </center>
  *
  * @see kiwi.util.ResourceManager#getURL
  * @see kiwi.util.ResourceLoader#getResourceAsURL
  *
  * @author Mark Lindner
  */

public class AboutFrame extends KFrame
  {
  private KButton b_ok, b_home = null;
  private JEditorPane edit;
  private URL startPage;
  private String defaultTitle = null;
  private _ActionListener actionListener;
  private LocaleData loc, loc2;
  private KPanel p_content;

 /** Construct a new <code>AboutFrame</code> without a <i>Home</i> button.
  *
  * @param title The title for the window.
  * @param source The URL of the initial HTML document to display.
  */
  
  public AboutFrame(String title, URL source)
    {
    this(title, source, false);
    }

  /** Construct a new <code>AboutFrame</code>.
    *
    * @param title The title for the window.
    * @param source The URL of the initial HTML document to display.
    * @param hasHomeButton A flag specifying whether the dialog will be created
    * with a <i>Home</i> button for URL navigation.
    */

  public AboutFrame(String title, URL source, boolean hasHomeButton)
    {
    super(title);

    defaultTitle = title;
    startPage = source;

    actionListener = new _ActionListener();

    loc = LocaleManager.getDefault().getLocaleData("KiwiDialogs");
    loc2 = LocaleManager.getDefault().getLocaleData("KiwiMisc");
    
    KPanel main = getMainContainer();    

    main.setLayout(new BorderLayout(5, 5));
    main.setBorder(KiwiUtils.defaultBorder);
    
    ButtonPanel p_buttons = new ButtonPanel();

    if(hasHomeButton)
      {
      b_home = new KButton(loc.getMessage("kiwi.button.home"));
      b_home.addActionListener(actionListener);
      b_home.setEnabled(false);
      p_buttons.addButton(b_home);
      }

    b_ok = new KButton(loc.getMessage("kiwi.button.close"));
    b_ok.addActionListener(actionListener);
    p_buttons.addButton(b_ok);

    addWindowListener(new WindowAdapter()
      {
      public void windowClosing(WindowEvent evt)
        {
        _hide();
        }
      });

    edit = new JEditorPane();

    // the order here is IMPORTANT!

    edit.setEditable(false);
    edit.addHyperlinkListener(new HyperlinkListener()
      {
      public void hyperlinkUpdate(HyperlinkEvent evt)
        {
        if(evt.getEventType() == HyperlinkEvent.EventType.ACTIVATED)
          {
          _showDocument(evt.getURL());
          if(b_home != null)
            b_home.setEnabled(true);
          }
        }
      });
    edit.setEditorKit(new HTMLEditorKit());
    
    KScrollPane scroll = new KScrollPane(edit);
    scroll.setHorizontalScrollBarPolicy(ScrollPaneConstants
      .HORIZONTAL_SCROLLBAR_NEVER);

    p_content = new KPanel();
    p_content.setLayout(new BorderLayout(5, 5));

    Component content = buildContentPanel();
    if(content != null)
      p_content.add("South", content);

    p_content.add("Center", scroll);
    
    main.add("Center", p_content);

    main.add("South", p_buttons);

    setSize(500, 600);
    }

  /** This method may be overridden to produce a component that will
   * be added below the HTML pane in the frame. This can be used to
   * provide additional content, in the frame. The default
   * implementation returns <code>null</code>.
   *
   * @return A component to add to the frame.
   *
   * @since Kiwi 1.3
   */

  protected Component buildContentPanel()
    {
    return(null);
    }
  
  /* hide the window */

  private void _hide()
    {
    setVisible(false);
    dispose();
    }

  /** Show or hide the window. */

  public void setVisible(boolean flag)
    {
    if(flag)
      _showDocument(startPage);

    super.setVisible(flag);
    }

  /** show document */

  private void _showDocument(URL url)
    {
    try
      {
      edit.setPage(url);
      String docTitle = (String)edit.getDocument()
        .getProperty(Document.TitleProperty);
      setTitle((docTitle != null) ? docTitle : defaultTitle);
      }
    catch(IOException ex)
      {
      _showError(url);
      }
    }
  
  /* show error message */

  private void _showError(URL url)
    {
    edit.setText(loc2.getMessage("kiwi.warning.html.doc_not_found",
                                 url.toString()));
    }

  /* handle button events */
  
  private class _ActionListener implements ActionListener
    {
    public void actionPerformed(ActionEvent evt)
      {
      Object o = evt.getSource();
      
      if(o == b_ok)
        _hide();
      
      else if((b_home != null) && (o == b_home))
        {
        _showDocument(startPage);
        b_home.setEnabled(false);
        }
      }
    }

  }

/* end of source file */