/**
 *#########################################################################
 *
 * A component of the Gatherer application, part of the Greenstone digital
 * library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * Copyright (C) 1999 New Zealand Digital Library Project
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *########################################################################
 */
package org.greenstone.gatherer.cdm;

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import org.greenstone.gatherer.Configuration;
import org.greenstone.gatherer.DebugStream;
import org.greenstone.gatherer.Dictionary;
import org.greenstone.gatherer.Gatherer;
import org.greenstone.gatherer.gui.DesignPaneHeader;
import org.greenstone.gatherer.gui.GComboBox;
import org.greenstone.gatherer.gui.GLIButton;
import org.greenstone.gatherer.metadata.MetadataElement;
import org.greenstone.gatherer.metadata.MetadataSetManager;
import org.greenstone.gatherer.util.CheckList;
import org.greenstone.gatherer.util.JarTools;
import org.greenstone.gatherer.util.StaticStrings;
import org.w3c.dom.*;
/** This class is resposible for storing the indexes which have been assigned to this collection and the default index, and providing methods for interacting with both these data pools. It also knows how to turn itself into a String as it would be displayed in the collection configuration file.
 * @author John Thompson, Greenstone Digital Library, University of Waikato
 * @version 2.3
 */
public class IndexManager
    extends DOMProxyListModel {

    static final private Dimension FIELD_SIZE = new Dimension(200,30);

    static final private String ALLFIELDS = "allfields";
    /** The controls for editing the indexes. */
    private Control controls = null;
    /** A model of the levels, also based on the DOM. */
    private DOMProxyListModel levels_model = null;
    /** A reference to ourselves so our inner methods have access. */
    private DOMProxyListModel model = null;
    /** The default index. */
    private Index default_index = null;

    /** Constructor. */
    public IndexManager(Element indexes) {
	super(indexes, CollectionConfiguration.INDEX_ELEMENT, new Index());
	DebugStream.println("IndexManager: " + getSize() + " indexes parsed.");
	model = this;
	// Parse and retrieve the default index
	NodeList default_index_elements = CollectionDesignManager.collect_config.getDocumentElement().getElementsByTagName(CollectionConfiguration.INDEX_DEFAULT_ELEMENT);
	if(default_index_elements.getLength() > 0) {
	    default_index = new Index((Element)default_index_elements.item(0));
	}
	// Parse and retrieve the levels element
	Element levels_element = CollectionDesignManager.collect_config.getLevels();
	levels_model = new DOMProxyListModel(levels_element, CollectionConfiguration.CONTENT_ELEMENT, new Level());
	DebugStream.println(" + " + levels_model.getSize() + " levels parsed.");
    }

    /** Method to add a new index.
     * @param index The <strong>Index</strong> to add.
     * @see org.greenstone.gatherer.Gatherer
     * @see org.greenstone.gatherer.collection.CollectionManager
     */
    private void addIndex(Index index, CollectionMeta metadatum) {
	///ystem.err.println("Adding an index: " + index.toString());
	if(!contains(index)) {
	    CollectionDesignManager.collectionmeta_manager.addMetadatum(metadatum);
	    // Retrieve the currently last index
	    if(getSize() > 0) {
		Index last_index = (Index)getElementAt(getSize() - 1);
		addAfter(index, last_index);
		
	    }
	    else {
		add(index);
		// Also set this index as the default one, 
		setDefault(index);
	    }
	    Gatherer.c_man.configurationChanged();
	}
	else {
	    JOptionPane.showMessageDialog(Gatherer.g_man, Dictionary.get("CDM.IndexManager.Index_Exists"), Dictionary.get("General.Warning"), JOptionPane.WARNING_MESSAGE);
	}
    }

    private void addLevel(Level level, CollectionMeta metadatum) {
	if(!levels_model.contains(level)) {
	    CollectionDesignManager.collectionmeta_manager.addMetadatum(metadatum);
	    // Retrieve the currently last level
	    if(levels_model.getSize() > 0) {
		Level last_level = (Level)levels_model.getElementAt(levels_model.getSize() - 1);
		levels_model.addAfter(level, last_level);
	    }
	    else {
		levels_model.add(level);
	    }
	    Gatherer.c_man.configurationChanged();
	}
	else {
	    JOptionPane.showMessageDialog(Gatherer.g_man, Dictionary.get("CDM.IndexManager.Level_Exists"), Dictionary.get("General.Warning"), JOptionPane.WARNING_MESSAGE);
	}
    }

    public void destroy() {
	if(controls != null) {
	    controls.destroy();
	    controls = null;
	}
	default_index = null;
	model = null;
    }

    /** Method to acquire the controls for editing the indexes.
     * @return the Control
     */
    public Control getControls() {
	if(controls == null) {
	    // Build controls
	    controls = new IndexControl();
	}
	return controls;
    }

    /** Method to get the default index.
     * @return The default <strong>Index</strong>.
     */
    public Index getDefault() {
	if(default_index != null && default_index.isAssigned()) {
	    return default_index;
	}
	else {
	    return null;
	}
    }

    /** Method to retrieve a certain index, as referenced by an index number.
     * @param index An <i>int</i> which indicates the position of the desired index.
     * @return The <strong>Index</strong> at the given index, or <i>null</i> if no such index exists.
     */
    public Index getIndex(int index) {
	if(0 <= index && index < getSize()) {
	    return (Index)getElementAt(index);
	}
	return null;
    }

    /** Method to retrieve a certain index, given its id.
     * @param id the id of the index as a String
     * @return the Index that matches id, or null if no such index exists
     */
    public Index getIndex(String id) {
	int size = getSize();
	for(int i = 0; i < size; i++) {
	    Index index = (Index) getElementAt(i);
	    if(index.getID().equals(id)) {
		return index;
	    }
	}
	return null;
    }

    public ArrayList getIndexes() {
	return children();
    }

    public Level getLevel(String name) {
	int levels_model_size = levels_model.getSize();
	for(int i = 0; i < levels_model_size; i++) {
	    Level level = (Level) levels_model.getElementAt(i);
	    if(level.getLevel().equals(name)) {
		return level;
	    }
	}
	return null;
    }

    public int getNumLevels() {
	return levels_model.getSize();
    }
    private void moveIndex(Index index, boolean move_up)
    {
	// Determine the current position of the index
	int position = indexOf(index);
	// Determine if it can be moved, ie if its not already at the top trying to move up, or at the bottom trying to move down.
	if(position == -1) {
	    return;
	}
	if(position == 0 && move_up) {
	    return;
	}
	if(position == (getSize()) - 1 && !move_up) {
	    return;
	}
	
	// Ok, move up
	if (move_up) {
	    position--;
	    remove(index);
	    add(position, index);
	}

	// Or move down
	else {
	    position++;
	    remove(index);
	    add(position, index);
	}

	// Schedule the collection for saving
	Gatherer.c_man.configurationChanged();
    }


    private void moveLevel(Level level, boolean move_up) {
	// Determine the leveles current position
	int position = levels_model.indexOf(level);
	// Determine if it can be moved, ie if its not already at the top trying to move up, or at the bottom trying to move down.
	if(position == -1) {
	    return;
	}
	if(position == 0 && move_up) {
	    return;
	}
	if(position == (levels_model.getSize()) - 1 && !move_up) {
	    return;
	}
	// Ok, move up
	if(move_up) {
	    position--;
	    levels_model.remove(level);
	    levels_model.add(position, level);
	}
	// Or move down
	else {
	    position++;
	    levels_model.remove(level);
	    levels_model.add(position, level);
	}
	// Schedule the collection for saving
	Gatherer.c_man.configurationChanged();
    }
    
    /** Method to remove a certain index.
     * @param index the Index to remove.
     * @see org.greenstone.gatherer.Gatherer
     * @see org.greenstone.gatherer.cdm.CollectionDesignManager
     * @see org.greenstone.gatherer.cdm.CollectionMetaManager
     * @see org.greenstone.gatherer.collection.CollectionManager
     */
    private void removeIndex(Index index) {
	if(index != null) {
	    // Remove any current metadata from this index
	    CollectionDesignManager.collectionmeta_manager.removeMetadata(CollectionConfiguration.STOP_CHARACTER + index.getID());
	    // Remove the index
	    remove(index);
	    // Check if the index removed happens to be the default index
	    if(default_index != null && default_index.equals(index)) {
		// If so our first solution is to set the first index to be default
		if(getSize() > 0) {
		    Index another_index = (Index) getElementAt(0);
		    setDefault(another_index);
		    another_index = null;
		}
		else {
		    default_index.setAssigned(false);
		}
	    } 
	    Gatherer.c_man.configurationChanged();
	}
    }

    private void removeLevel(Level level) {
	if(level != null) {
	    // Remove any current metadata from this level
	    CollectionDesignManager.collectionmeta_manager.removeMetadata(CollectionConfiguration.STOP_CHARACTER + level.getLevel());
	    // Remove the level
	    levels_model.remove(level);
	    Gatherer.c_man.configurationChanged();
	}
    }

    /* replace an index in the list. new index may have the same sources but a
       different name, or may be a new index altogether */
    private void replaceIndex(Index old_index, Index new_index,
			      CollectionMeta coll_meta) {
	if (old_index == null || new_index == null || coll_meta == null) {
	    return;
	}
	if (!old_index.getID().equals(new_index.getID()) && contains(new_index)) {
	    // shoudl we output an error??
	    return;
	}
	// Remove the old index coll meta
	CollectionDesignManager.collectionmeta_manager.removeMetadata(CollectionConfiguration.STOP_CHARACTER + old_index.getID());
	// Add the new coll meta
	CollectionDesignManager.collectionmeta_manager.addMetadatum(coll_meta);

	// get the position of the old one
	int position = indexOf(old_index);
	// remove it
	remove(old_index);
	// add the new one at that position
	add(position, new_index);

	// Schedule the collection for saving
	Gatherer.c_man.configurationChanged();
    }

    /** Method to set the default index.
     * @param index the new default Index
     * @see org.greenstone.gatherer.Gatherer
     * @see org.greenstone.gatherer.collection.CollectionManager
     */
    public void setDefault(Index index) {
	if(index != null) {
	    if(default_index == null) {
		// Create the default index element, and place immediately after indexes element.
		Element default_index_element = root.getOwnerDocument().createElement(CollectionConfiguration.INDEX_DEFAULT_ELEMENT);
		default_index = new Index(default_index_element);
		Node target_node = CollectionConfiguration.findInsertionPoint(default_index_element);
		if(target_node != null) {
		    root.getOwnerDocument().getDocumentElement().insertBefore(default_index_element, target_node);
		}
		else {
		    root.getOwnerDocument().getDocumentElement().appendChild(default_index_element);
		}
	    }
	    default_index.setAssigned(true);
	    default_index.setLevel(index.getLevel());
	    default_index.setSources(index.getSources());
	    
	}
	else {
	    if(default_index != null) {
		default_index.setAssigned(false);
	    }
	}
	Gatherer.c_man.configurationChanged();
    }

    /** This method is reponsible for changing the underlying Index commands from MG to MGPP and back again. This turns out to be easyish for MG->MGPP and very hard for the reverse. For the former we remove the level fragment and make sure the same levels are set, then we produce a list of the sources involved, breaking down comma seperated lists and making sure each item it unique. Changing back the other way turns out to be impossible, so we don't (beyond generating document:text, section:text and paragraph:text if text is an index and the respective levels are present). In either case we start by creating a comment containing the old index information.
     * @param  state true to enable MGPP indexes, false to use standard MG style ones
     */
    public void setMGPPEnabled(boolean state) {
	if(state == root.getAttribute(CollectionConfiguration.MGPP_ATTRIBUTE).equals(CollectionConfiguration.TRUE_STR)) {
	    // we are not changing state
	    return;
	    
	}
	// change MG -> MGPP
	if(state) {
	    Element mg_element = root;
	    // Retrieve and assign the MGPP indexes element.
	    Element mgpp_element = CollectionDesignManager.collect_config.getMGPPIndexes();
	    mgpp_element.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.TRUE_STR);
	    levels_model.root.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.TRUE_STR);
	    // If the MGPP indexes element is empty (ie was created by CollectionConfiguration), generate new MGPP index from the existing index
	    NodeList indexes = mgpp_element.getElementsByTagName(CollectionConfiguration.INDEX_ELEMENT);
	    if(indexes.getLength() == 0) {
		ArrayList levels_list = new ArrayList();
		ArrayList sources_list = new ArrayList();
		// We first use details from the default index if any
		if(default_index != null) {
		    int level_int = default_index.getLevel();
		    if(0 <= level_int && level_int < 3) {
			String level = Index.LEVEL[level_int];
			levels_list.add(level);
			level = null;
		    }
		    ArrayList sources = default_index.getSources();
		    sources_list.addAll(sources);
		}
		int size = getSize();
		for(int i = 0; i < size; i++) {
		    Index index = (Index) getElementAt(i);
		    int level_int = index.getLevel();
		    if(0 <= level_int && level_int < 3) {
			String level = Index.LEVEL[level_int];
			if(!levels_list.contains(level)) {
			    levels_list.add(level);
			}
			level = null;
		    }
		    ArrayList sources = index.getSources();
		    sources.removeAll(sources_list);
		    sources_list.addAll(sources);
		    index = null;
		}
		// Replace mg element with mgpp element
		setRoot(mgpp_element);
		
		// We now have a list of sources and a list of levels, so create new indexes and levels based on these
		int sources_list_size = sources_list.size();
		for(int j = 0; j < sources_list_size; j++) {
		    Object source_object = sources_list.get(j);
		    String source_str = null;
		    if(source_object instanceof MetadataElement) {
			source_str = ((MetadataElement) source_object).getFullName();
		    }
		    else {
			source_str = source_object.toString();
		    }
		    ArrayList new_sources = new ArrayList();
		    new_sources.add(source_object);
		    source_object = null;
		    Index new_index = new Index(new_sources);
		    // Try to retrieve existing metadatum
		    source_str = new_index.getID();
		    CollectionMeta metadatum = CollectionDesignManager.collectionmeta_manager.getMetadatum(CollectionConfiguration.STOP_CHARACTER + source_str, false);
		    // If no metadata was found, add new pseudo metadata using the id
		    if(metadatum == null) {
			metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + source_str);
			metadatum.setAssigned(true);
			metadatum.setValue(source_str);
		    }
		    // If it was found, ensure it is assigned
		    else {
			metadatum.setAssigned(true);
		    }
		    source_str = null;
		    addIndex(new_index, metadatum);
		    metadatum = null;
		    new_index = null;
		    new_sources = null;
		    source_str = null;
		}
		int levels_list_size = levels_list.size();
		for(int k = 0; k < levels_list_size; k++) {
		    String level_name = (String)levels_list.get(k);
		    Level new_level = new Level(level_name);
		    if(!levels_model.contains(new_level)) {
			CollectionMeta metadatum = CollectionDesignManager.collectionmeta_manager.getMetadatum(CollectionConfiguration.STOP_CHARACTER + level_name, false);
			// If no metadata was found, add new pseudo metadata using the id
			if(metadatum == null) {
			    metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + level_name);
			    metadatum.setAssigned(true);
			    metadatum.setValue(level_name);
			}
			addLevel(new_level, metadatum);
		    }
		    new_level = null;
		    
		}
	    }
	    else {
		// we already have mgpp indexes assigned
		// Replace mg element with mgpp element
		setRoot(mgpp_element);
	    }
	    // Unassign MG element and default index
	    mg_element.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.FALSE_STR);
	    mg_element = null;
	}
	// change MGPP -> MG
	else {
	    Element mgpp_element = root;
	    // Retrieve and assign MG element and default index element
	    Element mg_element = CollectionDesignManager.collect_config.getMGIndexes();
	    mg_element.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.TRUE_STR);
	    // If mg element has no indexes, and the current mgpp index include a text one, then generate text indexes for each of the registered levels.
	    NodeList indexes = mg_element.getElementsByTagName(CollectionConfiguration.INDEX_ELEMENT);
	    if(indexes.getLength() == 0) {
		Index index = getIndex(CollectionConfiguration.TEXT_STR);
		if(index != null) {
		    // Replace mgpp element with mg element
		    setRoot(mg_element);
		    int level_size = levels_model.getSize();
		    for(int i = 0; i < level_size; i++) {
			Level level = (Level) levels_model.getElementAt(i);
			Index new_index = new Index(level.getLevel(), index.getSources());
			// Try to retrieve existing metadatum
			String source_str = new_index.getID();
			CollectionMeta metadatum = CollectionDesignManager.collectionmeta_manager.getMetadatum(CollectionConfiguration.STOP_CHARACTER + source_str, false);
			// If no metadata was found, add new pseudo metadata using the id
			if(metadatum == null) {
			    metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + source_str);
			    metadatum.setAssigned(true);
			    metadatum.setValue(source_str);
			}
			// If it was found, ensure it is assigned
			else {
			    metadatum.setAssigned(true);
			}
			source_str = null;
			addIndex(new_index, metadatum);
			new_index = null;
			level = null;
		    }
		}
	    }
	    else {
		// Replace mgpp element with mg element
		setRoot(mg_element);
	    }
	    // Unassign mgpp element and levels
	    mgpp_element.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.FALSE_STR);
	    levels_model.root.setAttribute(CollectionConfiguration.ASSIGNED_ATTRIBUTE, CollectionConfiguration.FALSE_STR);
	}
	// its really hard to transfer defaults between mg and mgpp. so we'll just assign the first one to be the default.
	Index first_index = (Index) getElementAt(0);
	setDefault(first_index);
	first_index = null;
	
	
    }
    

    /** This class creates a set of controls for editing the indexes. */
    private class IndexControl
	extends JPanel
	implements Control {

	//	private JTextArea instruction_textarea; 

	private JList index_list;

	private JButton move_down_button;
	private JButton move_up_button;
	private JButton set_default_button;

	private JTextField name_textfield ;
	private CheckList source_list;
	// mg uses a level box
	private JComboBox level_combobox;
	// mgpp has a allfields selector
	private JCheckBox allfields_box;

	private JButton add_button;
	private JButton add_all_button;
	private JButton remove_button;
	private JButton replace_button;

	// soem panels that we need to manipulate later on
	private JPanel boxes_pane;
	private JPanel labels_pane;
	private JLabel level_label;
	private JPanel allfields_pane;
	
	// we add in a tabbed pane for mgpp mode
	private JTabbedPane tabbed_pane;
	// the main index set up pane
	private JPanel main_index_pane;

	// for the levels tab in mgpp mode
	private MGPPLevelsPanel mgpplevels_pane;

	private boolean mgpp_enabled = false;
	/** Constructor.
	 * @see org.greenstone.gatherer.Configuration
	 * @see org.greenstone.gatherer.Gatherer
	 * @see org.greenstone.gatherer.cdm.IndexManager.IndexControl.AddListener
	 * @see org.greenstone.gatherer.cdm.IndexManager.IndexControl.NameListener
	 * @see org.greenstone.gatherer.cdm.IndexManager.IndexControl.RemoveListener
	 * @see org.greenstone.gatherer.cdm.IndexManager.IndexControl.SetDefaultListener
	 * @see org.greenstone.gatherer.collection.CollectionManager
	 */
	public IndexControl() {
	    super();

	    ArrayList new_data = new ArrayList();
	    new_data.add(CollectionConfiguration.TEXT_STR);
	    new_data.addAll(MetadataSetManager.getEveryMetadataSetElement());
	    
	    // Creation
	    JPanel header_pane = new DesignPaneHeader("CDM.GUI.Indexes", "searchindexes");	    
	    JPanel assigned_indexes_pane = new JPanel();
	    JLabel index_label = new JLabel();
	    Dictionary.registerText(index_label, "CDM.IndexManager.Indexes");
	    index_list = new JList(model);
	    index_list.setCellRenderer(new IndexListRenderer());
	    index_list.setVisibleRowCount(2);
	    index_list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
	    
	    
	    JPanel movement_pane = new JPanel();
	    move_up_button = new JButton("", JarTools.getImage("arrow-up.gif"));
	    move_up_button.setEnabled(false);
	    move_up_button.setMnemonic(KeyEvent.VK_U);
	    Dictionary.registerBoth(move_up_button, "CDM.Move.Move_Up", "CDM.Move.Move_Up_Tooltip");

	    move_down_button = new JButton("", JarTools.getImage("arrow-down.gif"));
	    move_down_button.setEnabled(false);
	    move_down_button.setMnemonic(KeyEvent.VK_D);
	    Dictionary.registerBoth(move_down_button, "CDM.Move.Move_Down", "CDM.Move.Move_Down_Tooltip");
	    
	    set_default_button = new GLIButton();
	    set_default_button.setEnabled(false);
	    set_default_button.setMnemonic(KeyEvent.VK_S);
	    Dictionary.registerBoth(set_default_button, "CDM.IndexManager.Set_Default", "CDM.IndexManager.Set_Default_Tooltip");

	    JPanel new_index_pane = new JPanel();
	    JPanel details_pane = new JPanel();
	    labels_pane = new JPanel();
	    boxes_pane = new JPanel();
	    main_index_pane = new JPanel();

	    JLabel name_label = new JLabel();
	    Dictionary.registerText(name_label, "CDM.IndexManager.Index_Name");
	    name_textfield = new JTextField();
	    name_textfield.setPreferredSize(FIELD_SIZE);
	    Dictionary.registerTooltip(name_textfield, "CDM.IndexManager.Index_Name_Tooltip");

	    JLabel source_label = new JLabel();
	    Dictionary.registerText(source_label, "CDM.IndexManager.Source");
	    source_list = new CheckList(false);
	    source_list.setListData(new_data);
	    Dictionary.registerTooltip(source_list, "CDM.IndexManager.Source_Tooltip");

	    level_label = new JLabel();
	    Dictionary.registerText(level_label, "CDM.IndexManager.Level");
	    level_combobox = new JComboBox();
	    level_combobox.setPreferredSize(FIELD_SIZE);
	    level_combobox.addItem(CollectionConfiguration.DOCUMENT_STR);//Dictionary.get("CDM.IndexManager.Document"));
	    level_combobox.addItem(CollectionConfiguration.PARAGRAPH_STR);//Dictionary.get("CDM.IndexManager.Paragraph"));
	    level_combobox.addItem(CollectionConfiguration.SECTION_STR);//Dictionary.get("CDM.IndexManager.Section"));
	    level_combobox.setEditable(false);
	    Dictionary.registerTooltip(level_combobox, "CDM.IndexManager.Level_Tooltip");

	    JPanel button_pane = new JPanel();
	    add_button = new GLIButton();
	    add_button.setEnabled(false);
	    add_button.setMnemonic(KeyEvent.VK_A);
	    Dictionary.registerBoth(add_button, "CDM.IndexManager.Add_Index", "CDM.IndexManager.Add_Index_Tooltip");

	    add_all_button = new GLIButton();
	    add_all_button.setEnabled(true);
	    add_all_button.setMnemonic(KeyEvent.VK_L);
	    Dictionary.registerBoth(add_all_button, "CDM.IndexManager.MGPP.Add_All_Metadata", "CDM.IndexManager.MGPP.Add_All_Metadata_Tooltip");

	    remove_button = new GLIButton();
	    remove_button.setEnabled(false);
	    remove_button.setMnemonic(KeyEvent.VK_R);
	    Dictionary.registerBoth(remove_button, "CDM.IndexManager.Remove_Index", "CDM.IndexManager.Remove_Index_Tooltip");
	    replace_button = new GLIButton();
	    replace_button.setEnabled(false);
	    replace_button.setMnemonic(KeyEvent.VK_P);
	    Dictionary.registerBoth(replace_button, "CDM.IndexManager.MGPP.Replace_Index", "CDM.IndexManager.MGPP.Replace_Index_Tooltip");

	    allfields_pane = new JPanel();
	    allfields_box = new JCheckBox();
	    JLabel allfields_label = new JLabel();
	    Dictionary.registerText(allfields_label, "CDM.IndexManager.Allfields_Index");
	    allfields_pane.setLayout(new BorderLayout());
	    allfields_pane.add(allfields_box, BorderLayout.WEST);
	    allfields_pane.add(allfields_label, BorderLayout.CENTER);
	    
	    // Listeners
	    add_button.addActionListener(new AddListener());
	    add_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    add_all_button.addActionListener(new AddAllActionListener());
	    add_all_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    remove_button.addActionListener(new RemoveListener());
	    remove_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    replace_button.addActionListener(new ReplaceListener());
	    replace_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    move_down_button.addActionListener(new MoveListener(false));
	    move_down_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    move_up_button.addActionListener(new MoveListener(true));
	    move_up_button.addActionListener(CollectionDesignManager.buildcol_change_listener);
	    set_default_button.addActionListener(new SetDefaultListener());
	    set_default_button.addActionListener(CollectionDesignManager.buildcol_change_listener);

	    name_textfield.getDocument().addDocumentListener(new NameListener());
	    level_combobox.addItemListener(new LevelListener());
	    index_list.addListSelectionListener(new IndexListListener());
	    source_list.addListSelectionListener(new SourceListListener());
	    allfields_box.addItemListener(new AllfieldsCheckBoxListener());

	    // Layout

	    movement_pane.setBorder(BorderFactory.createEmptyBorder(0,2,0,0));
	    movement_pane.setLayout(new GridLayout(3,1));
	    movement_pane.add(move_up_button);
	    movement_pane.add(move_down_button);
	    movement_pane.add(set_default_button);

	    assigned_indexes_pane.setBorder(BorderFactory.createEmptyBorder(0,0,5,0));
	    assigned_indexes_pane.setLayout(new BorderLayout());
	    assigned_indexes_pane.add(index_label, BorderLayout.NORTH);
	    assigned_indexes_pane.add(new JScrollPane(index_list), BorderLayout.CENTER);
	    assigned_indexes_pane.add(movement_pane, BorderLayout.EAST);

	    labels_pane.setLayout(new BorderLayout());
	    labels_pane.setBorder(BorderFactory.createEmptyBorder(5, 5, 10, 5));
	    labels_pane.add(name_label, BorderLayout.NORTH);
	    labels_pane.add(source_label, BorderLayout.CENTER);
	    labels_pane.add(level_label, BorderLayout.SOUTH);
	    
	    boxes_pane.setLayout(new BorderLayout());
	    boxes_pane.add(name_textfield, BorderLayout.NORTH);
	    boxes_pane.add(new JScrollPane(source_list), BorderLayout.CENTER);
	    boxes_pane.add(level_combobox, BorderLayout.SOUTH);
	    
	    details_pane.setLayout(new BorderLayout());
	    details_pane.add(labels_pane, BorderLayout.WEST);
	    details_pane.add(boxes_pane, BorderLayout.CENTER);

	    button_pane.setLayout(new GridLayout(2,2,5,0));
	    button_pane.add(add_button);
	    button_pane.add(add_all_button);
	    button_pane.add(replace_button);
	    button_pane.add(remove_button);

	    new_index_pane.setLayout(new BorderLayout());
	    new_index_pane.add(details_pane, BorderLayout.CENTER);
	    new_index_pane.add(button_pane, BorderLayout.SOUTH);

	    main_index_pane.setLayout(new BorderLayout());
	    main_index_pane.add(assigned_indexes_pane, BorderLayout.NORTH);
	    main_index_pane.add(new_index_pane, BorderLayout.CENTER);

	    setBorder(BorderFactory.createEmptyBorder(0,5,0,0));
	    setLayout(new BorderLayout());
	    add(header_pane, BorderLayout.NORTH);
	    add(main_index_pane, BorderLayout.CENTER);

	    // for later, if we go to MGPP mode
	    tabbed_pane = new JTabbedPane();
	}

	
	/* Destructor, removes persistant listeners from the Dictionary.
	 */
	public void destroy() {
	}

	public void gainFocus() {
	    boolean old_mgpp_enabled = mgpp_enabled;
	    mgpp_enabled = CollectionDesignManager.searchtype_manager.isSearchTypeEnabled();
	    boolean changed_state = (old_mgpp_enabled != mgpp_enabled);
	    if (changed_state) {
		// reset the underlying indexes and levels elements
		setMGPPEnabled(mgpp_enabled);
	    }
	    /* reset the source list - may have built between then and now */
	    ArrayList new_data = new ArrayList();
	    new_data.add(CollectionConfiguration.TEXT_STR);
	    new_data.addAll(MetadataSetManager.getEveryMetadataSetElement());
	    source_list.setListData(new_data);
	    new_data = null;
	    
	    if(mgpp_enabled) {
		if (changed_state) {
		    // switch the variable bits
		    boxes_pane.remove(level_combobox);
		    labels_pane.remove(level_label);
		    boxes_pane.add(allfields_pane, BorderLayout.SOUTH);
		    //put back the tabbed pane
		    remove(main_index_pane);
		    add(tabbed_pane, BorderLayout.CENTER);
		    tabbed_pane.insertTab(Dictionary.get("CDM.IndexManager.MGPP.Indexes"), null, main_index_pane, null, 0);
		    if (mgpplevels_pane == null) {
			mgpplevels_pane = new MGPPLevelsPanel();
			tabbed_pane.insertTab(Dictionary.get("CDM.IndexManager.MGPP.Levels"), null, mgpplevels_pane, null, 1);
		    }
		    index_list.setSelectedIndex(0);
		    
		}
	    }
	    else {
		if (changed_state) {
		    boxes_pane.remove(allfields_pane);
		    boxes_pane.add(level_combobox, BorderLayout.SOUTH);
		    labels_pane.add(level_label, BorderLayout.SOUTH);
		    remove(tabbed_pane);
		    tabbed_pane.remove(0);
		    add(main_index_pane, BorderLayout.CENTER);
		    source_list.setEnabled(true); // in case it had been disabled
		    allfields_box.setSelected(false);
		    index_list.setSelectedIndex(0);
		    
		}
	    }
	    updateControlsWithSelectedIndex();
	    
	}

	public void loseFocus() {
	}
	
	private void updateControlsWithSelectedIndex() {
	    
	    Index selected_index = (Index)index_list.getSelectedValue();
	    if (selected_index == null) {
		return;
	    }
	    String id = selected_index.getID();
	    if (id == null || id.equals("")) {
		return;
	    }
	    String name = CollectionDesignManager.collectionmeta_manager.getMetadatum("." + id).getValue(true);
	    name_textfield.setText(name);
	    if (!mgpp_enabled) {
		level_combobox.setSelectedIndex(selected_index.getLevel());
	    }
	    source_list.clearTicked();
	    ArrayList sources = selected_index.getSources();
	    if (mgpp_enabled && sources.get(0).equals(ALLFIELDS)) {
		source_list.setEnabled(false);
		allfields_box.setSelected(true);
	    } else {
		source_list.setTickedObjects(sources.toArray());
		source_list.setEnabled(true);
		allfields_box.setSelected(false);
	    }
	}
	
	private void validateAddButton() {

	    String new_index_name = name_textfield.getText();
	    // indexes must have a name
	    if (new_index_name.length() == 0) {
		add_button.setEnabled(false);
		replace_button.setEnabled(false);
		return;
	    }
	    
	    boolean add_enabled = false;
	    boolean replace_enabled = false;
	    
	    Index index;
	    ArrayList sources;
	    if (mgpp_enabled && allfields_box.isSelected()) {
		sources = new ArrayList();
		sources.add(ALLFIELDS);
		index = new Index(sources);

	    } else if (!source_list.isNothingTicked()) {
		Object object[] = source_list.getTicked().toArray();
		sources = new ArrayList();
		for(int i = 0; i < object.length; i++) {
		    sources.add(object[i]);
		}
		object = null;
		
		if (mgpp_enabled) {
		    index = new Index(sources);
		} else {
		    index = new Index(level_combobox.getSelectedIndex(), sources);
		}
	    } else {
		add_button.setEnabled(false);
		replace_button.setEnabled(false);
		return;
	    }
	    sources = null;
	    if (model.contains(index)) {
		add_enabled = false;
		// may be able to replace if the index selected is the same but with a different name
		if (index_list.getSelectedIndex() != -1) {
		    String id = index.getID();
		    String selected_index_id = ((Index)index_list.getSelectedValue()).getID();
		    if (id.equals(selected_index_id)) {
			// check the name
			String existing_index_name = CollectionDesignManager.collectionmeta_manager.getMetadatum(CollectionConfiguration.STOP_CHARACTER+id).getValue(true);
			if (!existing_index_name.equals(new_index_name)) {
			    replace_enabled = true;
			}
		    }
		}
	    } else {
		add_enabled = true;
		if (index_list.getSelectedIndex() != -1) {
		    // there is something selected, so we can replace
		    replace_enabled = true;
		}
	    }
	    
	    // We should now know the button state
	    add_button.setEnabled(add_enabled);
	    replace_button.setEnabled(replace_enabled);
	}
	
	private class AddListener
	    implements ActionListener
	{
	    public void actionPerformed(ActionEvent event)
	    {
		String name = name_textfield.getText();
		if (name.length() == 0) return;
		Index index;
		if (mgpp_enabled && allfields_box.isSelected()) {
		    ArrayList sources = new ArrayList();
		    sources.add(ALLFIELDS);
		    index = new Index(sources);
		}
		else if (!source_list.isNothingTicked()) {
		    ArrayList sources = source_list.getTicked();
		    if(mgpp_enabled) {
			index = new Index(sources);
		    } else {
			index = new Index(level_combobox.getSelectedIndex(), sources);
		    }
		} else {
		    return;
		}
		 
		// Before we add the index to the model, we have to add the collection metadata for this
		CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + index.getID());
		metadatum.setValue(name);
		
		// Finally, add the index
		addIndex(index, metadatum);
		index_list.setSelectedValue(index, true);
		add_button.setEnabled(false);
		
	    }
	}

	/** add all sources as indexes. for MG, this adds them in one combined
	    index, for MGPP this adds them as individual indexes (fields) */
	private class AddAllActionListener
	    implements ActionListener {

	    public void actionPerformed(ActionEvent event) {
		ArrayList all_sources = source_list.getAll();
		if (!mgpp_enabled) {
		    Index index = new Index(level_combobox.getSelectedIndex(), all_sources);
		    if (!model.contains(index)) {
			CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + index.getID());
			metadatum.setValue("all fields"); // need a good name
			addIndex(index, metadatum);
		    }
		    all_sources = null;
		    index = null;
		    return;
		}
		
		ArrayList new_sources = new ArrayList();
		for(int i = 0; i < all_sources.size(); i++) {
		    Object source = all_sources.get(i);

		    // Create new index
		    new_sources.clear();
		    new_sources.add(source);
		    Index index = new Index(new_sources);
		    if(!model.contains(index)) {
			// Determine the metadatum value
			String name = source.toString();
			if(name.startsWith(StaticStrings.EXTRACTED_NAMESPACE)) {
			    name = name.substring(StaticStrings.EXTRACTED_NAMESPACE.length());
			}
			// Create new metadatum
			CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + index.getID());
			metadatum.setValue(name);
			name = null;
			// Assign new index
			addIndex(index, metadatum);
		    }
		    source = null;
		    index = null;
		}
		new_sources = null;
		// Done. Disable add
		add_button.setEnabled(false);
	    }
	}

	private class AllfieldsCheckBoxListener
	    implements ItemListener
	{
	    public void itemStateChanged(ItemEvent event) {
		if (event.getStateChange() == ItemEvent.SELECTED) {
		    source_list.setEnabled(false);
		} else if (event.getStateChange() == ItemEvent.DESELECTED) {
		    source_list.setEnabled(true);
		}
		validateAddButton();
	    }

	}
	/** Listens for selections within the list on the IndexManager controls, and if a change is detected enables, or disables, controls appropriately. */
	private class IndexListListener
	    implements ListSelectionListener
	{
	    /** This method is called whenever the source list selection changes. When it does we need to fill in the various parts of the list description panel
	     * @param event A <strong>ListSelectionEvent</strong> containing further information about the list selection.
	     */
	    public void valueChanged(ListSelectionEvent event)
	    {
		if (event.getValueIsAdjusting()) {
		    return;
		}

		Object value = index_list.getSelectedValue();
		if (value == null) {
		    move_down_button.setEnabled(false);
		    move_up_button.setEnabled(false);
		    remove_button.setEnabled(false);
		    replace_button.setEnabled(false);
		    set_default_button.setEnabled(false);
		    return;
		}

		// Enable the buttons appropriately
		remove_button.setEnabled(true);
		set_default_button.setEnabled(default_index == null || !default_index.equals(value));
		int i = index_list.getSelectedIndex();
		int size = index_list.getModel().getSize();
		move_up_button.setEnabled((i>0));
		move_down_button.setEnabled((i<size-1));

		// Need to fill in the rest of the bits
		updateControlsWithSelectedIndex();		
	    }
	}

	private class IndexListRenderer
	    extends DefaultListCellRenderer {

	    /** Return a component that has been configured to display the specified value. */
	    public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
		JLabel component = (JLabel) super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
		if(default_index != null && default_index.equals(value)) {
		    component.setText(component.getText() + " " + Dictionary.get("CDM.IndexManager.Default_Index_Indicator"));
		}
		return component;
	    }

	}

	private class LevelListener
	    implements ItemListener {
	    public void itemStateChanged(ItemEvent event) {
		if(event.getStateChange() == ItemEvent.SELECTED) {
		    // just want to validate the add button
		    validateAddButton();

		}
	    }
	}

	private class MoveListener
	    implements ActionListener {

	    private boolean move_up;

	    public MoveListener(boolean move_up) {
		this.move_up = move_up;
	    }

	    public void actionPerformed(ActionEvent event) {
		// Retrieve the selected index
		Index index = (Index) index_list.getSelectedValue();
		if(index != null) {
		    moveIndex(index, move_up);
		    // Ensure the index that moved is still selected
		    index_list.setSelectedValue(index, true);
		    index = null;
		}
	    }
	}


	/** Listens for key presses within the name field, and enabled or disables controls as appropriate. */
	private class NameListener
	    implements DocumentListener
	{
	    public void changedUpdate(DocumentEvent e)
	    {
		validateAddButton();
	    }

	    public void insertUpdate(DocumentEvent e)
	    {
		validateAddButton();
	    }

	    public void removeUpdate(DocumentEvent e)
	    {
		validateAddButton();
	    }
	}


	private class RemoveListener
	    implements ActionListener
	{
	    public void actionPerformed(ActionEvent event)
	    {
		int i = index_list.getSelectedIndex();
		if (i != -1) {
		    removeIndex((Index) index_list.getSelectedValue());
		}
		int size = index_list.getModel().getSize();
		if (i == size) {
		    i--;
		}
		index_list.setSelectedIndex(i);
		// This will produce an event on the list, updating the other buttons
		if (size == 0) {
		    // We have removed the last index, should be able to add what's filled in currently, if valid
		    validateAddButton();
		}
	    }
	}


	private class ReplaceListener
	    implements ActionListener
	{
	    public void actionPerformed(ActionEvent event)
	    {
		if (index_list.isSelectionEmpty()) {
		    // This should never happen, but just in case...
		    replace_button.setEnabled(false);
		    return;
		}
		
		String name = name_textfield.getText();
		if (name.length() == 0) {
		    // this also should never happen...
		    add_button.setEnabled(false);
		    replace_button.setEnabled(false);
		    return;
		}
		ArrayList sources;
		Index index = null;
		if (mgpp_enabled && allfields_box.isSelected()) {
		    sources = new ArrayList();
		    sources.add(ALLFIELDS);
		    index = new Index(sources);
		} 
		else if (!source_list.isNothingTicked()) {
		    sources = source_list.getTicked();
		    if (mgpp_enabled) {
			index = new Index(sources);
		    } else {
			index = new Index(level_combobox.getSelectedIndex(), sources);
		    }
		}
		if (index != null) {
		    // Create the new collection meta
		    CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + index.getID());
		    metadatum.setValue(name);
		    
		    // replace the index
		    replaceIndex((Index) index_list.getSelectedValue(), index, metadatum);
		    index_list.setSelectedValue(index, true);
		    
		}
		add_button.setEnabled(false);
		replace_button.setEnabled(false);
	    }
	}


	private class SetDefaultListener
	    implements ActionListener {

	    public void actionPerformed(ActionEvent event) {
		Index index = (Index) index_list.getSelectedValue();
		if(index != null) {
		    setDefault(index);
		    // This should cause a repaint of just the desired row
		    index_list.setSelectedValue(index, true);
		}
		set_default_button.setEnabled(false);
	    }
	}


	private class SourceListListener
	    implements ListSelectionListener
	{
	    public void valueChanged(ListSelectionEvent event)
	    {
		validateAddButton();
	    }
	}
    }

    private class MGPPLevelsPanel
	extends JPanel {

	private JList current_levels_list;
	
	private JButton move_level_down_button;
	private JButton move_level_up_button;

	private GComboBox level_combobox;
	private JTextField level_name_field;

	private JButton add_level_button;
	private JButton remove_level_button;
			
	public MGPPLevelsPanel() {

	    JPanel current_levels_panel = new JPanel();

	    JLabel current_levels_label = new JLabel();
	    Dictionary.registerText(current_levels_label, "CDM.IndexManager.MGPP.Current_Levels");

	    current_levels_list = new JList(levels_model);
	    current_levels_list.setVisibleRowCount(5);
	    current_levels_list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
	    JPanel level_movement_panel = new JPanel();

	    move_level_up_button = new JButton("", JarTools.getImage("arrow-up.gif"));
	    move_level_up_button.setEnabled(false);
	    move_level_up_button.setMnemonic(KeyEvent.VK_U);
	    Dictionary.registerBoth(move_level_up_button, "CDM.Move.Move_Up", "CDM.Move.Move_Up_Tooltip");

	    move_level_down_button = new JButton("", JarTools.getImage("arrow-down.gif"));
	    move_level_down_button.setEnabled(false);
	    move_level_down_button.setMnemonic(KeyEvent.VK_D);
	    Dictionary.registerBoth(move_level_down_button, "CDM.Move.Move_Down", "CDM.Move.Move_Down_Tooltip");

	    JPanel level_spacer_panel = new JPanel();
	    JPanel level_body_panel = new JPanel();
	    JPanel level_details_panel = new JPanel();
	    JPanel level_labels_panel = new JPanel();
	    JPanel level_boxes_panel = new JPanel();

	    JLabel level_name_label = new JLabel();
	    Dictionary.registerText(level_name_label, "CDM.IndexManager.MGPP.Level_Name");

	    level_name_field = new JTextField();
	    level_name_field.setPreferredSize(FIELD_SIZE);
	    Dictionary.registerTooltip(level_name_field, "CDM.IndexManager.MGPP.Level_Name_Tooltip");


	    JLabel level_label = new JLabel();
	    Dictionary.registerText(level_label, "CDM.IndexManager.MGPP.Level");

	    level_combobox = new GComboBox(Index.LEVEL);
	    level_combobox.setPreferredSize(FIELD_SIZE);
	    level_combobox.setBackgroundNonSelectionColor(Configuration.getColor("coloring.editable_background", false));
	    level_combobox.setBackgroundSelectionColor(Configuration.getColor("coloring.collection_selection_background", false));
	    level_combobox.setEditable(false);
	    level_combobox.setTextNonSelectionColor(Configuration.getColor("coloring.workspace_tree_foreground", false));
	    level_combobox.setTextSelectionColor(Configuration.getColor("coloring.collection_selection_foreground", false));
	    Dictionary.registerTooltip(level_combobox, "CDM.IndexManager.Level_Tooltip");

	    JPanel level_button_panel = new JPanel();

	    add_level_button = new GLIButton("CDM.IndexManager.MGPP.Add_Level");
	    add_level_button.setEnabled(false);
	    add_level_button.setMnemonic(KeyEvent.VK_A);
	    Dictionary.registerBoth(add_level_button, "CDM.IndexManager.MGPP.Add_Level", "CDM.IndexManager.MGPP.Add_Level_Tooltip");

	    remove_level_button = new GLIButton("CDM.IndexManager.MGPP.Remove_Level");
	    remove_level_button.setEnabled(false);
	    remove_level_button.setMnemonic(KeyEvent.VK_A);
	    Dictionary.registerBoth(remove_level_button, "CDM.IndexManager.MGPP.Remove_Level", "CDM.IndexManager.MGPP.Remove_Level_Tooltip");

	    JPanel level_empty_panel = new JPanel();

	    // Connect Levels
	    EnableAddLevelListener level_eal = new EnableAddLevelListener();
	    add_level_button.addActionListener(new AddLevelActionListener());
	    current_levels_list.addListSelectionListener(new CurrentLevelsListSelectionListener());
	    level_combobox.addActionListener(level_eal);
	    // not editable
	    //((JTextField)level_combobox.getEditor().getEditorComponent()).getDocument().addDocumentListener(level_eal);
	    level_name_field.getDocument().addDocumentListener(level_eal);
	    move_level_down_button.addActionListener(new MoveLevelDownListener());
	    move_level_up_button.addActionListener(new MoveLevelUpListener());
	    remove_level_button.addActionListener(new RemoveLevelActionListener());
	    // Layout Levels

	    level_movement_panel.setLayout(new GridLayout(2,1));
	    level_movement_panel.add(move_level_up_button);
	    level_movement_panel.add(move_level_down_button);

	    current_levels_panel.setLayout(new BorderLayout());
	    current_levels_panel.add(current_levels_label, BorderLayout.NORTH);
	    current_levels_panel.add(new JScrollPane(current_levels_list), BorderLayout.CENTER);
	    current_levels_panel.add(level_movement_panel, BorderLayout.EAST);

	    level_labels_panel.setLayout(new GridLayout(2,1));
	    level_labels_panel.add(level_name_label);
	    level_labels_panel.add(level_label);

	    level_boxes_panel.setLayout(new GridLayout(2,1));
	    level_boxes_panel.add(level_name_field);
	    level_boxes_panel.add(level_combobox);

	    level_details_panel.setLayout(new BorderLayout(5,0));
	    level_details_panel.add(level_labels_panel, BorderLayout.WEST);
	    level_details_panel.add(level_boxes_panel, BorderLayout.CENTER);

	    level_button_panel.setBorder(BorderFactory.createEmptyBorder(5,0,0,0));
	    level_button_panel.setLayout(new GridLayout(1,2,5,0));
	    level_button_panel.add(add_level_button);
	    level_button_panel.add(remove_level_button);

	    level_body_panel.setBorder(BorderFactory.createEmptyBorder(5,0,0,0));
	    level_body_panel.setLayout(new BorderLayout());
	    level_body_panel.add(level_details_panel, BorderLayout.CENTER);
	    level_body_panel.add(level_button_panel, BorderLayout.SOUTH);

	    level_spacer_panel.setLayout(new BorderLayout());
	    level_spacer_panel.add(level_body_panel, BorderLayout.NORTH);
	    level_spacer_panel.add(level_empty_panel, BorderLayout.CENTER);

	    setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
	    setLayout(new BorderLayout());
	    add(current_levels_panel, BorderLayout.NORTH);
	    add(level_spacer_panel, BorderLayout.CENTER);
	}
	
	public void gainFocus() {
	    // Ensure the level manager has at least documents assigned
	    if(levels_model.getSize() == 0) {
		Level level = new Level(CollectionConfiguration.DOCUMENT_STR);
		// Create new metadatum
		CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + CollectionConfiguration.DOCUMENT_STR);
		metadatum.setValue(CollectionConfiguration.DOCUMENT_STR);
		// Assign new level
		addLevel(level, metadatum);	    
		level = null;
	    }
	}

	/** Change the enable state of the add button depending on the current value in the search type combobox. */
	public void validateAddButtonLevel() {
	    String name = level_name_field.getText();
	    Object selected_object = level_combobox.getSelectedItem();
	    if(name.length() > 0 && selected_object != null) {
		add_level_button.setEnabled(getLevel((String)selected_object) == null);
	    }
	    else {
		add_level_button.setEnabled(false);
	    }
	}

	private class AddLevelActionListener
	    implements ActionListener {
	    public void actionPerformed(ActionEvent event) {
		// Retrieve the name
		String name = level_name_field.getText();
		// Retrieve the source
		String source = (String)level_combobox.getSelectedItem();
		Level level = new Level(source);
		// Create new metadatum
		CollectionMeta metadatum = new CollectionMeta(CollectionConfiguration.STOP_CHARACTER + source);
		metadatum.setValue(name);
		// Assign new level
		int size = levels_model.getSize();
		addLevel(level, metadatum);
		current_levels_list.setSelectedValue(level, true);
		add_level_button.setEnabled(false);
	    }
	}

	private class CurrentLevelsListSelectionListener
	    implements ListSelectionListener {
	    public void valueChanged(ListSelectionEvent event) {
		
		if(event.getValueIsAdjusting()) {
		    return;
		}
		
		Level level = (Level)current_levels_list.getSelectedValue();
		if(level != null) {
		    String full_text = level.toString();
		    if(full_text.indexOf("\"") != -1) {
			level_name_field.setText(level.getName());
		    }
		    String level_id = level.getLevel();
		    level_combobox.setSelectedItem(level_id);
		    move_level_down_button.setEnabled((levels_model.indexOf(level) < levels_model.getSize() - 1));
		    move_level_up_button.setEnabled((levels_model.indexOf(level) > 0));
		    remove_level_button.setEnabled(true);
		}
		else {
		    move_level_down_button.setEnabled(false);
		    move_level_up_button.setEnabled(false);
		    remove_level_button.setEnabled(false);
		}
	    }
	}
	
	private class EnableAddLevelListener
	    implements ActionListener, DocumentListener {
	    /** Called whenever a selection action occurs on the combobox.
	     * @param  event an ActionEvent containing information about the selection event
	     */
	    public void actionPerformed(ActionEvent event) {
		validateAddButtonLevel();
	    }

	    /** Gives notification that an attribute or set of attributes changed.
	     * @param  event a DocumentEvent containing information about the text changed
	     */
	    public void changedUpdate(DocumentEvent event) {
		validateAddButtonLevel();
	    }

	    /** Gives notification that there was an insert into the document.
	     * @param  event a DocumentEvent containing information about the text added
	     */
	    public void insertUpdate(DocumentEvent event) {
		validateAddButtonLevel();
	    }

	    /** Gives notification that a portion of the document has been removed.
	     * @param  event a DocumentEvent containing information about the text removed
	     */
	    public void removeUpdate(DocumentEvent event) {
		validateAddButtonLevel();
	    }
    
	}
	private class MoveLevelDownListener
	    implements ActionListener {
	    public void actionPerformed(ActionEvent event) {
		// Retrieve the first selected item
		Level level = (Level) current_levels_list.getSelectedValue();
		moveLevel(level, false);
		current_levels_list.setSelectedValue(level, true);
	    }
	}
	private class MoveLevelUpListener
	    implements ActionListener {
	    public void actionPerformed(ActionEvent event) {
		// Retrieve the first selected item
		Level level = (Level) current_levels_list.getSelectedValue();
		moveLevel(level, true);
		current_levels_list.setSelectedValue(level, true);
	    }
	}
	private class RemoveLevelActionListener
	    implements ActionListener {

	    public void actionPerformed(ActionEvent event) {
		
		int i = current_levels_list.getSelectedIndex();
		if (i != -1) {
		    Level level = (Level) current_levels_list.getSelectedValue();
		    CollectionDesignManager.collectionmeta_manager.removeMetadata(CollectionConfiguration.STOP_CHARACTER + level.getLevel());
		    removeLevel(level);
		    if (i == current_levels_list.getModel().getSize()) {
			i--;
		    }
		    current_levels_list.setSelectedIndex(i);
		}		
		if (i==-1) {
		    // Disable remove button
		    remove_level_button.setEnabled(false);
		}
		validateAddButtonLevel();
	    }
	}

    }

}