source: trunk/gli/src/org/greenstone/gatherer/cdm/MetadataSetView.java@ 8243

/**
 *#########################################################################
 *
 * 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.GLIButton;
import org.greenstone.gatherer.mem.MetadataEditorManager;
import org.greenstone.gatherer.msm.MetadataSet;
import org.greenstone.gatherer.msm.MSMEvent;
import org.greenstone.gatherer.msm.MSMListener;
import org.w3c.dom.*;

/** This class only knows how to produce a simple visual representation of the currently imported metadata sets. It is also read-only, so should be fairly straight forward.
 * @author John Thompson, Greenstone Digital Library, University of Waikato
 * @version 2.3d
 */
public class MetadataSetView
    extends DynamicListModel
    implements MSMListener {
    /** The visual contols used to review the metadata sets. */
    private Control controls = null;
    /** A reference to ourselves so our inner classes can refer to us. */
    private DynamicListModel model = null;

    /** Constructor.
     */
    public MetadataSetView() {
    DebugStream.println("MetadataSetView: Initialized.");
    model = this;
    Gatherer.c_man.getCollection().msm.addMSMListener(this);
    loadMetadataSets();
    // Build the controls
    controls = new MetadataSetControl();
    }

    /** Destructor. Remove any references of this class from persistant objects.
     * @see org.greenstone.gatherer.Gatherer
     * @see org.greenstone.gatherer.collection.CollectionManager
     */
    public void destroy() {
    controls.destroy();
    controls = null;
    Gatherer.c_man.msm.removeMSMListener(this);
    model = null;
    }

    /** Called when an element is changed within a set in the MSM, prompting us to refresh our list of elements being shown.
     * @param event A <strong>MSMEvent</strong> which encapsulates relevant data about the change.
     * @see org.greenstone.gatherer.cdm.MetadataSetView.MetadataSetControl
     */
    public void elementChanged(MSMEvent event) {
    // Get the controls to refresh element list.
    ((MetadataSetControl)controls).refreshElementList();
    }

    /** A method for retrieve the controls for this manager.
     * @see org.greenstone.gatherer.Dictionary
     * @see org.greenstone.gatherer.gui.Coloring
     */
    public Control getControls() {
    return controls;
    }

    /** Called when a metadata value has undergone significant change.
     * @param event A <strong>MSMEvent</strong> which encapsulates relevant data about the change.
     */
    public void metadataChanged(MSMEvent event) {
    // Couldn't care less.
    }

    /** Called when a set is added or removed from the MSM.
     * @param event A <strong>MSMEvent</strong> which encapsulates relevant data about the change.
     */
    public void setChanged(MSMEvent event) {
    // Reload model.
    clear();
    loadMetadataSets();
    }


    /** Prints out the contents of this manager, as they would appear in the collection configuration file.
     * @return A <strong>String</strong> containing a block of commands.
     * @see org.greenstone.gatherer.cdm.MetadataSetView.SetWrapper
     */
    public String toString() {
    String text = "";
    for(int i = 0; i < size(); i++) {
        SetWrapper set = (SetWrapper)get(i);
        text = text + set.toString() + "\n";
    }
    text = text + "\n";
    return text;
    }

    /** Called when a significant change has occured to a value tree for a certain element, however we take no further action.
     * @param event A <strong>MSMEvent</strong> containing information relevant to the event.
     */
    public void valueChanged(MSMEvent event) {
    }

    /** Retrieves the current list of loaded metadata sets, and builds a list model around them.
     * @see org.greenstone.gatherer.Gatherer
     * @see org.greenstone.gatherer.cdm.MetadataSetView.SetWrapper
     * @see org.greenstone.gatherer.collection.CollectionManager
     */
    private void loadMetadataSets() {
    // We initialize the set_model with wrapped metadata sets. Note that when we call getSets() we also end up adding ourselves as a listener to the metadata set manager.
    Vector sets = Gatherer.c_man.getCollection().msm.getSets();
    for(int i = 0; i < sets.size(); i++) {
        addElement(new SetWrapper((MetadataSet)sets.get(i)));
    }
    }

    /** This class creates and lays-out the various controls for reviewing the metadata sets, and their commands as they would appear in the collection configuration file. */
    private class MetadataSetControl
    extends JPanel
    implements Control {
    /** Listens for clicks upon the configure button, or double clicks from the metadata set list. */
    private ConfigureActionListener configure_action_listener;
    /** Opens the MEM and systematically performs as if the add set button were clicked. */
    private JButton add_button;
    /** Opens the MEM with the appropriate set open for editing. */
    private JButton configure_button;
    /** Opens the MEM and systematically performs as if the remove set button were clicked. */
    private JButton remove_button;
    /** The label denoting the element list. */
    private JLabel element_label = null;
    /** The label denoting the set list. */
    private JLabel set_label = null;
    /** The title of these controls. */
    private JLabel title = null;
    /** The list of elements for the choosen set. */
    private JList element_list = null;
    /** The list of sets in this collection. */
    private JList set_list = null;
    /** The panel onto which all other panels will be placed. */
    private JPanel central_pane = null;
    /** The panel onto which the element list will be placed. */
    private JPanel element_pane = null;
    /** The panel containing the title and instructions. */
    private JPanel header_pane = null;
    /** The panel containing the set list. */
    private JPanel set_pane = null;

    private JScrollPane element_list_scroll_pane;
    /** The text area of inline instructions. */
    private JTextArea instructions = null;

    private ListListener list_listener;

    private MultilingualListCellRenderer element_list_cell_renderer;

    /** The element model for the currently selected set. */
    private Vector element_model = null;

    /* Constructor.
     * @see org.greenstone.gatherer.Coloring;
     * @see org.greenstone.gatherer.Dictionary
     * @see org.greenstone.gatherer.cdm.MetadataSetView.ListListener
     */
    public MetadataSetControl() {
        // Create visual components
        central_pane = new JPanel();
        element_label = new JLabel();
        element_label.setHorizontalAlignment(JLabel.CENTER);
        element_label.setOpaque(true);
        Dictionary.registerText(element_label, "CDM.MetadataSetManager.Elements");
        element_list_scroll_pane = new JScrollPane();
        element_list_cell_renderer = new MultilingualListCellRenderer(element_list_scroll_pane);
        element_list = new JList();
        element_list_scroll_pane.setViewportView(element_list);
        element_list.setCellRenderer(element_list_cell_renderer);
        element_list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        element_pane = new JPanel();
        header_pane = new JPanel();
        instructions = new JTextArea();
        instructions.setBackground(Configuration.getColor("coloring.collection_tree_background", false));
        instructions.setEditable(false);
        instructions.setLineWrap(true);
        instructions.setRows(6);
        instructions.setWrapStyleWord(true);
        Dictionary.registerText(instructions, "CDM.MetadataSetManager.Instructions");
        set_label = new JLabel();
        set_label.setHorizontalAlignment(JLabel.CENTER);
        set_label.setOpaque(true);
        Dictionary.registerText(set_label, "CDM.MetadataSetManager.Sets");
        set_list = new JList(model);
        set_list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        if(model.size() > 0) {
        set_list.setSelectedIndex(0);
        }

        set_pane = new JPanel();
        title = new JLabel();
        title.setHorizontalAlignment(JLabel.CENTER);
        title.setOpaque(true);
        Dictionary.registerText(title, "CDM.MetadataSetManager.Title");

        JPanel button_pane = new JPanel();
        add_button = new GLIButton();
        add_button.setEnabled(true);
        add_button.setMnemonic(KeyEvent.VK_A);
        Dictionary.registerBoth(add_button, "CDM.MetadataSetManager.Add", "CDM.MetadataSetManager.Add_Tooltip");
        configure_button = new GLIButton();
        configure_button.setEnabled(false);
        configure_button.setMnemonic(KeyEvent.VK_C);
        Dictionary.registerBoth(configure_button, "CDM.MetadataSetManager.Configure", "CDM.MetadataSetManager.Configure_Tooltip");
        remove_button = new GLIButton();
        remove_button.setEnabled(false);
        remove_button.setMnemonic(KeyEvent.VK_R);
        Dictionary.registerBoth(remove_button, "CDM.MetadataSetManager.Remove", "CDM.MetadataSetManager.Remove_Tooltip");
        configure_action_listener = new ConfigureActionListener();
        list_listener = new ListListener();

        // Add listeners
        add_button.addActionListener(new AddButtonListener());
        configure_button.addActionListener(configure_action_listener);
        remove_button.addActionListener(new RemoveButtonListener());
        set_list.addListSelectionListener(list_listener);
        set_list.addMouseListener(configure_action_listener);
        // Layout
        instructions.setBorder(BorderFactory.createEmptyBorder(2,5,2,5));

        header_pane.setLayout(new BorderLayout());
        header_pane.add(title, BorderLayout.NORTH);
        header_pane.add(new JScrollPane(instructions), BorderLayout.CENTER);

        set_pane.setLayout(new BorderLayout());
        set_pane.add(set_label, BorderLayout.NORTH);
        set_pane.add(new JScrollPane(set_list), BorderLayout.CENTER);

        element_pane.setLayout(new BorderLayout());
        element_pane.add(element_label, BorderLayout.NORTH);
        element_pane.add(element_list_scroll_pane, BorderLayout.CENTER);

        central_pane.setLayout(new GridLayout(2,1));
        central_pane.add(set_pane);
        central_pane.add(element_pane);
        
        button_pane.setBorder(BorderFactory.createEmptyBorder(5,0,0,0));
        button_pane.setLayout(new GridLayout(1,3,0,0));
        button_pane.add(add_button);
        button_pane.add(configure_button);
        button_pane.add(remove_button);

        setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
        setLayout(new BorderLayout());
        add(header_pane, BorderLayout.NORTH);
        add(central_pane, BorderLayout.CENTER);
        add(button_pane, BorderLayout.SOUTH);
    }
    /** Destructor. */
    public void destroy() {
    }
    /** Update the element list. */
    public void refreshElementList() {
        element_list.updateUI();
    }

    /** Overriden to ensure the instruction area is scrolled to top.
     */
    public void gainFocus() {
        if(instructions != null) {
        instructions.setCaretPosition(0);
        }
        // If no current selection, select first available set
        if(set_list.isSelectionEmpty() && set_list.getModel().getSize() > 0) {
        set_list.setSelectedIndex(0);
        list_listener.valueChanged(new ListSelectionEvent(set_list, 0, 0, true));
        }
    }

    public void loseFocus() {
    }

    /** Listens for clicks on the add button, and actions them accordingly by opening the MEM and clicking add set. */
    private class AddButtonListener
        implements ActionListener {
        /** Called when the add button is clicked.
         * @param event an ActionEvent containing information about the mouse click
         * @see org.greenstone.gatherer.Gatherer
         * @see org.greenstone.gatherer.collection.Collection
         * @see org.greenstone.gatherer.collection.CollectionManager
         * @see org.greenstone.gatherer.mem.MetadataEditorManager
         */
        public void actionPerformed(ActionEvent event) {
        Gatherer.c_man.getCollection().msm.editMDS(null, MetadataEditorManager.ADD_SET);
        }
    }

    /** Listens for clicks on the configure button or double clicks upon the metadata set list and chains to the MEM as appropriate. */
    private class ConfigureActionListener
        extends MouseAdapter 
        implements ActionListener {
        /** Called when the configure button is clicked.
         * @param event an ActionEvent containing information about the mouse click
         */
        public void actionPerformed(ActionEvent event) {
        configureSet();
        }

        /** Called whenever the mouse is clicked over a registered component, we use this to chain through to the configure prompt.
         * @param event a MouseEvent containing information about the mouse click
        */
        public void mouseClicked(MouseEvent event) {
        if(event.getClickCount() == 2 ) {
            configureSet();
        }
        }
        /** If some set is selected, then open the metadata set manager with the current set selected and expanded 
         * @see org.greenstone.gatherer.Gatherer
         * @see org.greenstone.gatherer.collection.Collection
         * @see org.greenstone.gatherer.collection.CollectionManager
         * @see org.greenstone.gatherer.cdm.MetadataSetView.SetWrapper
         * @see org.greenstone.gatherer.mem.MetadataEditorManager
         */
        private void configureSet() {
        if(!set_list.isSelectionEmpty()) {
            MetadataSet set = ((SetWrapper)set_list.getSelectedValue()).getSet();
            Gatherer.c_man.getCollection().msm.editMDS(set, MetadataEditorManager.NORMAL);
        }
        else {
            configure_button.setEnabled(false);
        }
        }
    }

    private class ListListener
        implements ListSelectionListener {
        public void valueChanged(ListSelectionEvent event) {
        // Wait until we get a stable event
        if(event.getValueIsAdjusting()) {
            return;
        }
        // Now we can process it
        if(!set_list.isSelectionEmpty()) {
            MetadataSet set = ((SetWrapper)set_list.getSelectedValue()).getSet();
            NodeList elements = set.getElements();
            element_model = new Vector();
            for(int i = 0; i < elements.getLength(); i++) {
            element_model.add(new ElementWrapper(elements.item(i)));
            }
            //Collections.sort(element_model);
            element_list.setListData(element_model);
            configure_button.setEnabled(true);
            remove_button.setEnabled(true);

            // Finally check the directionality and scroll as necessary
            JScrollBar scroll_bar = element_list_scroll_pane.getHorizontalScrollBar();
            if(element_list_cell_renderer.getDirectionality() == Character.DIRECTIONALITY_RIGHT_TO_LEFT) {
            scroll_bar.setValue(scroll_bar.getMaximum());
            }
            else {
            scroll_bar.setValue(scroll_bar.getMinimum());
            }

        }
        else {
            configure_button.setEnabled(false);
            remove_button.setEnabled(false);
        }
        }
    }

    /** Listens for clicks on the remove button, and actions them accordingly by opening the MEM and clicking remove set. */
    private class RemoveButtonListener
        implements ActionListener {
        /** Called when the remove button is clicked.
         * @param event an ActionEvent containing information about the mouse click
         * @see org.greenstone.gatherer.Gatherer
         * @see org.greenstone.gatherer.collection.Collection
         * @see org.greenstone.gatherer.collection.CollectionManager
         * @see org.greenstone.gatherer.cdm.MetadataSetView.SetWrapper
         * @see org.greenstone.gatherer.mem.MetadataEditorManager
         */
        public void actionPerformed(ActionEvent event) {
        if(!set_list.isSelectionEmpty()) {
            MetadataSet set = ((SetWrapper)set_list.getSelectedValue()).getSet();
            Gatherer.c_man.getCollection().msm.editMDS(set, MetadataEditorManager.REMOVE_SET);
        }
        else {
            remove_button.setEnabled(false);
        }
        }
    }

    private class MultilingualListCellRenderer
        extends DefaultListCellRenderer {
        private byte previous_directionality = Character.DIRECTIONALITY_UNDEFINED;
        private JScrollPane scroll_pane;
        public MultilingualListCellRenderer(JScrollPane scroll_pane) {
        super();
        this.scroll_pane = scroll_pane;
        }

        public byte getDirectionality() {
        if(previous_directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT || previous_directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC || previous_directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING || previous_directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE) {
            return Character.DIRECTIONALITY_RIGHT_TO_LEFT;
        }
        else {
            return Character.DIRECTIONALITY_LEFT_TO_RIGHT;
        }
        }
        
        public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        JLabel component = (JLabel) super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
        // Determine if the text should be left aligned or right aligned
        String text = value.toString();
        int text_index = 0;
        byte directionality = Character.DIRECTIONALITY_UNDEFINED;
        while(directionality == Character.DIRECTIONALITY_UNDEFINED && text_index < text.length()) {
            directionality = Character.getDirectionality(text.charAt(text_index));
            text_index++;
        }
        if(directionality != previous_directionality) {
            previous_directionality = directionality;
            if(directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE) {
            ///ystem.err.println("R2L for: " + text);
            component.setHorizontalAlignment(JLabel.TRAILING);
            component.setHorizontalTextPosition(JLabel.TRAILING);
            component.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
            //scroll_pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
            }
            else {
            component.setHorizontalAlignment(JLabel.LEADING);
            component.setHorizontalTextPosition(JLabel.LEADING);
            ///ystem.err.println("L2R for: " + text);
            component.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
            //scroll_pane.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
            }
        }

        text = null;
        return component;
        }

    }
    
    }

    /** Provides a convience wrapper around a metadata set, that allows it to appear in the <strong>JList</strong> the same way it would in the collection configuration file. */
    private class SetWrapper {
    private MetadataSet set = null;
    public SetWrapper(MetadataSet set) {
        this.set = set;
    }
    public MetadataSet getSet() {
        return set;
    }
    public String toString() {
        String namespace = set.getNamespace();
        // Watch out for the greenstone set, with its namespace of ""
        return "metadataset " + namespace + " \"" + set.getName() + "\"";
    }
    }
}