/*
 * SimplyHTML, a word processor based on Java, HTML and CSS
 * Copyright (C) 2002 Ulrich Hilger
 *
 * This program 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 program 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 program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package com.lightdev.app.shtm;

import java.awt.Frame;
import javax.swing.JPanel;
import javax.swing.JList;
import javax.swing.JButton;
import javax.swing.JLabel;
import java.awt.BorderLayout;
import java.util.Enumeration;
import javax.swing.border.EtchedBorder;
import javax.swing.JComboBox;
import javax.swing.border.TitledBorder;
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JCheckBox;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.event.ListSelectionEvent;
import javax.swing.JScrollPane;
import java.awt.Dimension;

/**
 * User interface for changing plug-in settings.
 *
 * @author Ulrich Hilger
 * @author Light Development
 * @author <a href="http://www.lightdev.com">http://www.lightdev.com</a>
 * @author <a href="mailto:info@lightdev.com">info@lightdev.com</a>
 * @author published under the terms and conditions of the
 *      GNU General Public License,
 *      for details see file gpl.txt in the distribution
 *      package of this software
 *
 * 
 */

class PluginManagerDialog extends DialogShell implements
    ListSelectionListener, ActionListener
{
  /** combo box for selecting the dock location */
  private JComboBox dockLocation;

  /** indicates if we can ignore changes (when happenig programmatically */
  private boolean ignoreChanges = false;

  /** the list with available plug-ins */
  private JList pluginNames;

  /** constant for activation button label */
  private String activateName = Util.getResourceString("activatePlugin");

  /** constant for deactivation button label */
  private String deactivateName = Util.getResourceString("deactivatePlugin");

  /** button to toggle plug-in activation state */
  private JButton toggleActivationButton;

  /** checkbox to toggle plug-in activation state */
  private JCheckBox toggleActivationCheckbox;

  /**
   * construct a new <code>PluginManagerDialog</code>
   *
   * @param parent  the parent frame
   * @param title  the title of the dialog
   */
  public PluginManagerDialog(Frame parent, String title) {
    super(parent, title);
    Container contentPane = super.getContentPane();

    okButton.setText(Util.getResourceString("close"));
    cancelButton.setVisible(false);

    GridBagLayout g;
    GridBagConstraints c = new GridBagConstraints();

    /** create panel to show and select plug-ins */
    JPanel pluginPanel = new JPanel(new BorderLayout());
    pluginPanel.setBorder(
        new TitledBorder(new EtchedBorder(EtchedBorder.LOWERED),
        Util.getResourceString("pluginPanelTitle")));
    //pluginPanel.setMinimumSize(new Dimension(400, 400));

    /** load a list with plug-in names and add it to the plug-in panel */
    Enumeration plugins = SHTMLPanelImpl.pluginManager.plugins();
    pluginNames = new JList(SHTMLPanelImpl.pluginManager.getPluginNames());
    pluginNames.addListSelectionListener(this);
    pluginNames.setMinimumSize(new Dimension(250, 400));
    pluginNames.setPreferredSize(new Dimension(250, 400));
    pluginPanel.add(new JScrollPane(pluginNames), BorderLayout.CENTER);

    /** create panel for actins on loaded plug-ins */
    JPanel actionPanel = new JPanel();
    toggleActivationButton = new JButton(activateName);
    toggleActivationButton.setEnabled(false);
    toggleActivationButton.addActionListener(this);
    actionPanel.add(toggleActivationButton);
    pluginPanel.add(actionPanel, BorderLayout.SOUTH);

    /** create panel to edit settings for a plug-in */
    g = new GridBagLayout();
    JPanel pluginSettingsPanel = new JPanel(g);
    toggleActivationCheckbox = new JCheckBox("togglePluginActivationCheckbox");
    toggleActivationCheckbox.setEnabled(false);
    toggleActivationCheckbox.addActionListener(this);
    Util.addGridBagComponent(pluginSettingsPanel, toggleActivationCheckbox,
                             g, c, 0, 0, GridBagConstraints.WEST);

    Util.addGridBagComponent(pluginSettingsPanel, new JLabel(
        Util.getResourceString("dockLocationLabel")),
                             g, c, 0, 1, GridBagConstraints.EAST);
    String[] locations = {
      Util.getResourceString("pluginDockLocationNone"),
      Util.getResourceString("pluginDockLocationTop"),
      Util.getResourceString("pluginDockLocationRight"),
      Util.getResourceString("pluginDockLocationBottom"),
      Util.getResourceString("pluginDockLocationLeft"),
    };
    dockLocation = new JComboBox(locations);
    dockLocation.setEnabled(false);
    dockLocation.addActionListener(this);
    Util.addGridBagComponent(pluginSettingsPanel, dockLocation, g, c,
                             1, 1, GridBagConstraints.WEST);

    /** add components to dialog */
    contentPane.add(pluginPanel, BorderLayout.WEST);
    JPanel centerPanel = new JPanel(new BorderLayout());
    JPanel centerWestPanel = new JPanel(new BorderLayout());
    centerWestPanel.add(pluginSettingsPanel, BorderLayout.NORTH);
    centerPanel.add(centerWestPanel, BorderLayout.WEST);
    centerPanel.setBorder(
        new TitledBorder(new EtchedBorder(EtchedBorder.LOWERED),
        Util.getResourceString("pluginSettingsPanelTitle")));
    //centerPanel.setPreferredSize(new Dimension(200,400));
    contentPane.add(centerPanel, BorderLayout.CENTER);

    pack();
  }

  /**
   * ListSelectionListener implementation
   */
  public void valueChanged(ListSelectionEvent e) {
    ignoreChanges = true;
    if(pluginNames.getSelectedIndex() > -1) {
      SHTMLPlugin p = getSelectedPlugin();
      boolean active = p.isActive();
      updateActivationButtonText(active);
      toggleActivationButton.setEnabled(true);
      toggleActivationCheckbox.setEnabled(true);
      toggleActivationCheckbox.setSelected(active);
      dockLocation.setSelectedIndex(p.getDockLocation());
      dockLocation.setEnabled(true);
    }
    else {
      toggleActivationButton.setEnabled(false);
      toggleActivationCheckbox.setEnabled(false);
      dockLocation.setEnabled(false);
    }
    ignoreChanges = false;
  }

  /**
   * helper method for getting the currently selected
   * line in the list of plug-ins
   */
  private SHTMLPlugin getSelectedPlugin() {
    String name = (String) pluginNames.getSelectedValue();
    return SHTMLPanelImpl.pluginManager.pluginForName(name);
  }

  /**
   * helper method to toggle the button text between
   * activate and deactivate
   */
  private void updateActivationButtonText(boolean active) {
    if(active) {
      toggleActivationButton.setText(deactivateName);
    }
    else {
      toggleActivationButton.setText(activateName);
    }
  }

  /**
   * ActionListener implementation
   */
  public void actionPerformed(ActionEvent e) {
    Object source = e.getSource();
    if((pluginNames.getSelectedIndex() > -1) && (!ignoreChanges)) {
      ignoreChanges = true;
      SHTMLPlugin p = getSelectedPlugin();
      if(source.equals(toggleActivationButton)) {
        p.setStatus(!p.isActive());
      }
      else if(source.equals(toggleActivationCheckbox)) {
        p.setStatus(!p.isActive());
      }
      else if(source.equals(dockLocation)) {
        p.setDockLocation(dockLocation.getSelectedIndex());
      }
      else {
        super.actionPerformed(e);
      }
      boolean active = p.isActive();
      toggleActivationCheckbox.setSelected(active);
      updateActivationButtonText(active);
      ignoreChanges = false;
    }
    else {
      super.actionPerformed(e);
    }
  }

}