/*

  *    Geotoolkit.org - An Open Source Java GIS Toolkit

  *    http://www.geotoolkit.org

  *

  *    (C) 2009-2012, Open Source Geospatial Foundation (OSGeo)

  *    (C) 2009-2012, Geomatys

  *

  *    This library is free software; you can redistribute it and/or

  *    modify it under the terms of the GNU Lesser General Public

  *    License as published by the Free Software Foundation;

  *    version 2.1 of the License.

  *

  *    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

  *    Lesser General Public License for more details.

  */

 package org.geotoolkit.gui.swing.image;

 import java.util.Map;

 import java.util.List;

 import java.util.Locale;

 import java.util.ArrayList;

 import java.util.LinkedHashMap;

 import java.util.IdentityHashMap;

 import java.awt.*;

 import java.awt.event.ActionEvent;

 import java.awt.event.ActionListener;

 import javax.swing.*;

 import javax.swing.tree.TreePath;

 import javax.swing.event.TreeSelectionEvent;

 import javax.swing.event.TreeSelectionListener;

 import javax.imageio.metadata.IIOMetadata;

 import javax.imageio.metadata.IIOMetadataFormat;

 import javax.imageio.metadata.IIOMetadataFormatImpl;

 import org.jdesktop.swingx.JXTreeTable;

 import org.geotoolkit.resources.Vocabulary;

 import org.geotoolkit.util.NumberRange;

 import org.geotoolkit.util.converter.Classes;

 import org.geotoolkit.image.io.metadata.MetadataTreeNode;

 import org.geotoolkit.image.io.metadata.MetadataTreeTable;

 import org.geotoolkit.image.io.metadata.SpatialMetadataFormat;

 import org.geotoolkit.internal.swing.ComboBoxRenderer;

 /**

  * A panel showing the content of an {@link IIOMetadata} instance. This panel contains three parts:

  * <p>

  * <ul>

  *  <li>At the top, a field allowing to select which metadata to display:

  *   <ul>

  *    <li>The metadata format, typically

  *        {@value org.geotoolkit.image.io.metadata.SpatialMetadataFormat#FORMAT_NAME} or

  *        {@value javax.imageio.metadata.IIOMetadataFormatImpl#standardMetadataFormatName}.

  *    </li>

  *    <li>The metadata part to display: <cite>stream</cite> metadata or one of the

  *        <cite>image</cite> metadata.</li>

  *   </ul>

  *  </li>

  *  <li>At the center, the metadata as a {@linkplain JXTreeTable tree table}.

  *      The columns are documented in {@link MetadataTreeTable} javadoc.</li>

  *  <li>At the bottom, a description of the currently selected metadata node.</li>

  * </ul>

  * <p>

  * Most columns are hiden by default. The initial view shows only (<var>name</var>, <var>value</var>) pairs in

  * the {@link IIOMetadata} case, or (<var>name</var>, <var>type</var>) pairs in the {@link IIOMetadataFormat}

  * case. Users can make additional columns visible by clicking on the icon in the upper-right corner.

  * <p>

  * This class can be used in two ways (choose only one):

  * <p>

  * <ul>

  *   <li>For displaying the structure of {@link IIOMetadataFormat} instances without data,

  *     invoke {@link #addMetadataFormat addMetadataFormat(...)}.</li>

  *

  *   <li>For displaying the actual content of {@link IIOMetadata} instances, invoke

  *     {@link #addMetadata addMetadata(...)}.</li>

  * </ul>

  *

  * <table cellspacing="24" cellpadding="12" align="center"><tr valign="top">

  * <td width="500" bgcolor="lightblue">

  * {@section Demo}

  * To try this component in your browser, see the

  * <a href="http://www.geotoolkit.org/demos/geotk-simples/applet/IIOMetadataPanel.html">demonstration applet</a>.

  * </td></tr></table>

  *

  * @author Martin Desruisseaux (Geomatys)

  * @version 3.12

  *

  * @see MetadataTreeTable

  *

  * @since 3.05

  * @module

  */

 @SuppressWarnings("serial")

 public class IIOMetadataPanel extends JComponent {

     /**

      * The choices of metadata format. Typical choices are

      * {@value org.geotoolkit.image.io.metadata.SpatialMetadataFormat#FORMAT_NAME} and

      * {@value javax.imageio.metadata.IIOMetadataFormatImpl#standardMetadataFormatName}.

      */

     private final DefaultComboBoxModel formatChoices;

     /**

      * The properties of the currently selected metadata node.

      */

     private final JLabel description, validValues;

     /**

      * The unique instance of the set of listeners which is associated to this panel.

      */

     private final Controller controller;

     /**

      * The name of images for each index. This is an undocumented feature for now.

      */

     transient List<String> imageNames;

     /**

      * Creates a panel with no initial metadata. One of the {@code addXXXMetadata} or

      * {@code addXXXMetadataFormat} methods should be invoked in order to display a content.

      */

     public IIOMetadataPanel() {

         setLayout(new BorderLayout());

         // If the preferred width is modified, consider updating the

         // preferred column width in IIOMetadataTreeTable constructor.

         setPreferredSize(new Dimension(500, 400));

         final JComponent tables = new JPanel(new CardLayout());

         add(tables, BorderLayout.CENTER);

         final Vocabulary resources = Vocabulary.getResources(getLocale());

         /*

          * Add the control button on top of the metadata table.

          */

         formatChoices = new DefaultComboBoxModel();

         final JComboBox formats = new JComboBox(formatChoices);

         ComboBoxRenderer.install(formats);

         formats.setName("Formats");

         if (true) {

             final JPanel controls = new JPanel(new GridBagLayout());

             final GridBagConstraints c = new GridBagConstraints();

             final Insets ci = c.insets;

             ci.left = 12;

             c.gridy=0; ci.top=6; ci.bottom=0;

             c.gridx=0; c.weightx=0; c.anchor=GridBagConstraints.WEST;

             controls.add(label(resources, Vocabulary.Keys.FORMAT, formats), c);

             c.insets.right = 12; c.insets.left = 0;

             c.gridx=1; c.weightx=1; c.fill=GridBagConstraints.BOTH;

             controls.add(formats, c);

             add(controls, BorderLayout.NORTH);

             controls.setOpaque(false);

         }

         /*

          * Add the section for metadata properties.

          */

         if (true) {

             final JPanel properties = new JPanel(new GridBagLayout());

             final GridBagConstraints c = new GridBagConstraints();

             final Insets ci = c.insets;

             c.gridx=1; c.weightx=1; c.anchor=GridBagConstraints.WEST;

             c.gridy=0; ci.top=3; ci.bottom=0; properties.add(description = new JLabel(), c);

             c.gridy++; ci.top=0; ci.bottom=3; properties.add(validValues = new JLabel(), c);

             ci.left = 6;

             c.gridx=0; c.weightx=0; ci.right=9;

             c.gridy=0; ci.top=3; ci.bottom=0; properties.add(label(resources, Vocabulary.Keys.DESCRIPTION,  description), c);

             c.gridy++; ci.top=0; ci.bottom=3; properties.add(label(resources, Vocabulary.Keys.VALID_VALUES, validValues), c);

             add(properties, BorderLayout.SOUTH);

             properties.setOpaque(false);

         }

         /*

          * Plug the listeners.

          */

         controller = new Controller(tables);

         formats.addActionListener(controller);

     }

     /**

      * Creates a new label for the given target component.

      */

     private static JLabel label(final Vocabulary resources, final int key, final JComponent target) {

         final JLabel label = new JLabel(resources.getLabel(key));

         label.setLabelFor(target);

         return label;

     }

     /**

      * Various interfaces that we need to implement. We do that in an internal class

      * in order to avoid exposing publicly the methods that we implement. Only one

      * instance of this class is created for an instance of {@code IIOMetdataPanel}.

      *

      * @author Martin Desruisseaux (Geomatys)

      * @version 3.08

      *

      * @since 3.05

      * @module

      */

     private final class Controller implements ActionListener, TreeSelectionListener {

         /**

          * The component which hold every tables. This is the component that appear in the center of

          * this {@code IIOMetadataPanel}. Its layout manager must be an instance of {@link CardLayout}.

          */

         private final JComponent tables;

         /**

          * The selected format, or {@code null} if none.

          */

         private IIOMetadataChoice selectedFormat;

         /**

          * The table which is currently visible, or {@code null} if none.

          */

         private IIOMetadataTreeTable visibleTable;

         /**

          * Creates a new instance.

          */

         Controller(final JComponent tables) {

             this.tables = tables;

         }

         /**

          * Resets this controller in the same state than after construction.

          */

         final void reset() {

             // Do not set visibleTable to null, because we want to copy its layout

             // when a new table will be created even if the previous table was for

             // an other image.

             selectedFormat = null;

             tables.removeAll();

         }

         /**

          * Invoked when a new format has been selected in the combo box.

          * When a change is detected, the tree is immediately updated.

          */

         @Override

         public void actionPerformed(final ActionEvent event) {

             final JComboBox choices = (JComboBox) event.getSource();

             final IIOMetadataChoice oldFormat = selectedFormat;

             final Object selected = choices.getSelectedItem();

             if (!(selected instanceof IIOMetadataChoice)) {

                 /*

                  * This happen if the user selected the separator.

                  */

                 choices.setSelectedItem(oldFormat);

                 return;

             }

             final IIOMetadataChoice newFormat = (IIOMetadataChoice) selected;

             if (newFormat == null) {

                 /*

                  * May be null if the user selected the choice which was already selected,

                  * which have the effect of unselecting it. We want the current format to

                  * stay selected.

                  */

                 choices.setSelectedItem(oldFormat);

                 return;

             }

             if (newFormat == oldFormat) {

                 return;

             }

             show(newFormat);

         }

         /**

          * Shows the {@code TreeTable} associated with the given choice.

          * It is the caller's responsibility to ensure that the given

          * format is the one selected in the combo box.

          */

         final void show(final IIOMetadataChoice newFormat) {

             selectedFormat = newFormat;

             visibleTable = newFormat.show(tables, this, visibleTable);

             showProperties(visibleTable.selectedNode);

         }

         /**

          * Invoked when a node has been selected.

          */

         @Override

         public void valueChanged(final TreeSelectionEvent event) {

             final TreePath path = event.getNewLeadSelectionPath();

             if (path != null) {

                 final MetadataTreeNode node = (MetadataTreeNode) path.getLastPathComponent();

                 visibleTable.selectedNode = node;

                 showProperties(node);

             }

         }

     }

     /**

      * Fills the "properties" section in the bottom of this {@code IIOMetadataPanel}

      * using the information provided by the given node.

      *

      * @param node The selected node, for which to display the information in the bottom

      *        of this panel. Can be null.

      */

     final void showProperties(final MetadataTreeNode node) {

         if (node == null) {

             description.setText(null);

             validValues.setText(null);

         } else {

             /*

              * Get the description of the given node. If no description is found for that node,

              * search for the parent until a description is found. We do that way mostly because

              * when an element contains only one attribute, some format don't provide a description

              * for that attribute since it is redundant with the element description.

              */

             MetadataTreeNode parent = node;

             String text;

             do text = parent.getDescription();

             while (text == null && (parent = parent.getParent()) != null);

             if (text == null) {

                 text = node.getLabel();

             }

             description.setText(text);

             /*

              * Now get the description of valid values. If there is none, we will build

              * one from the data type.

              */

             Object restriction = node.getValueRestriction();

             if (restriction == null) {

                 Class<?> type = node.getValueType();

                 if (type != null) {

                     if (type.isArray()) {

                         type = type.getComponentType();

                     }

                     StringBuilder buffer = new StringBuilder(Classes.getShortName(type));

                     final NumberRange<Integer> occurrences = node.getOccurrences();

                     if (occurrences != null) {

                         final String s = occurrences.toString();

                         if (s.startsWith("[")) {

                             buffer.append(s);

                         } else {

                             buffer.append('[').append(s).append(']');

                         }

                     }

                     restriction = buffer;

                 }

             }

             validValues.setText(restriction != null ? restriction.toString() : null);

         }

     }

     /**

      * Removes all metadata from this widget. After the invocation of this method,

      * this panel will be in the same state than after construction.

      */

     public void clear() {

         formatChoices.removeAllElements();

         controller   .reset();

     }

     /**

      * Clears the previous metadata content and adds the values of the given <em>stream</em> and

      * <em>image</em> metadata. Invoking this method is equivalent to invoking {@link #clear()}

      * followed by {@link #addMetadata(IIOMetadata, IIOMetadata[]) addMetadata(...)}, except that

      * the metadata initially show will be for the same format than the one currently selected,

      * if this format exists in the new metadata.

      *

      * @param stream The stream metadata, or {@code null} if none.

      * @param image  The image metadata for each image in a file.

      *

      * @since 3.09

      */

     public void setMetadata(final IIOMetadata stream, final IIOMetadata... image) {

         final Object selected = formatChoices.getSelectedItem();

         clear();

         addMetadata(stream, image);

         final int index = formatChoices.getIndexOf(selected);

         if (index > 0) { // Intentionnaly skip the first choice, since it is already selected.

             final Object newFormat = formatChoices.getElementAt(index);

             if (newFormat instanceof IIOMetadataChoice) {

                 formatChoices.setSelectedItem(newFormat);

                 controller.show((IIOMetadataChoice) newFormat);

             }

         }

     }

     /**

      * Adds to this panel the values of the given <em>stream</em> and <em>image</em> metadata.

      * Note that this method is typically invoked alone; there is no need to invoke

      * {@link #addMetadataFormat addMetadataFormat} prior this method.

      *

      * @param stream The stream metadata, or {@code null} if none.

      * @param image  The image metadata for each image in a file.

      */

     public void addMetadata(final IIOMetadata stream, final IIOMetadata... image) {

         final Map<IIOMetadata,Integer> imageIndex = new IdentityHashMap<IIOMetadata,Integer>();

         final Map<String, List<IIOMetadata>> metadataForNames =

                 new LinkedHashMap<String, List<IIOMetadata>>();

         addFormatNames(stream, metadataForNames);

         imageIndex.put(stream, -1);

         if (image != null) {

             for (int i=0; i<image.length; i++) {

                 final IIOMetadata metadata = image[i];

                 addFormatNames(metadata, metadataForNames);

                 imageIndex.put(metadata, i);

             }

         }

         /*

          * At this point, we grouped every metadata by format name and we remember the

          * image index for each metadata. Now process to the addition to the combo box.

          * If the format is already present in the combo box, insert right after the

          * existing format.

          */

         final Locale locale = getLocale();

         for (final Map.Entry<String, List<IIOMetadata>> entry : metadataForNames.entrySet()) {

             int insertAt = -1; // Where to insert, or -1 for adding to the end of the list.

             final String formatName = entry.getKey();

             for (int i=formatChoices.getSize(); --i>=0;) {

                 final Object existing = formatChoices.getElementAt(i);

                 if (existing instanceof IIOMetadataChoice) {

                     if (formatName.equals(((IIOMetadataChoice) existing).getFormatName())) {

                         insertAt = i;

                         break;

                     }

                 }

             }

             if (insertAt < 0 && formatChoices.getSize() != 0) {

                 formatChoices.addElement(ComboBoxRenderer.SEPARATOR);

             }

             final List<String> names = imageNames;

             final int namesCount = (names != null) ? names.size() : 0;

             for (final IIOMetadata metadata : entry.getValue()) {

                 final int index = imageIndex.get(metadata); // Should never be null.

                 final String name = (index >= 0 && index < namesCount) ? names.get(index) : null;

                 final IIOMetadataChoice choice = new IIOMetadataChoice(locale, formatName, metadata, index, name);

                 if (insertAt >= 0) {

                     formatChoices.insertElementAt(choice, ++insertAt);

                 } else {

                     formatChoices.addElement(choice);

                 }

             }

         }

     }

     /**

      * Adds the metadata format names to the keys of the given map, and the metadata

      * to the values. The given metadata can be {@code null} (as authorized by the

      * {@link #addMetadata} method contract), in which case it is ignored.

      */

     private static void addFormatNames(final IIOMetadata metadata,

             final Map<String, List<IIOMetadata>> metadataForNames)

     {

         if (metadata != null) {

             final String[] formatNames = metadata.getMetadataFormatNames();

             moveAtEnd(formatNames, IIOMetadataFormatImpl.standardMetadataFormatName);

             moveAtEnd(formatNames, metadata.getNativeMetadataFormatName());

             for (final String formatName : formatNames) {

                 List<IIOMetadata> list = metadataForNames.get(formatName);

                 if (list == null) {

                     list = new ArrayList<IIOMetadata>();

                     metadataForNames.put(formatName, list);

                 }

                 list.add(metadata);

             }

         }

     }

     /**

      * If the {@code toMove} name is found in the given array, move it at the end of the array.

      */

     private static void moveAtEnd(final String[] names, final String toMove) {

         if (toMove != null) {

             for (int i=0; i<names.length; i++) {

                 final String name = names[i];

                 if (toMove.equals(name)) {

                     System.arraycopy(names, i+1, names, i, names.length - (i+1));

                     names[names.length - 1] = name;

                     break;

                 }

             }

         }

     }

     /**

      * Adds to this panel the description of the given <em>stream</em> and <em>image</em>

      * metadata formats. The descriptions contain no metadata value, only the name of the

      * nodes together with a few additional information (type, valid values, <i>etc.</i>).

      *

      * @param stream The stream metadata format, or {@code null} if none.

      * @param image  The image metadata format, or {@code null} if none.

      */

     public void addMetadataFormat(final IIOMetadataFormat stream, final IIOMetadataFormat image) {

         final Locale locale = getLocale();

         if (stream != null) {

             formatChoices.addElement(new IIOMetadataChoice(locale, stream, true));

         }

         if (image != null) {

             formatChoices.addElement(new IIOMetadataChoice(locale, image, false));

         }

     }

     /**

      * Adds to this panel the description of

      * {@value org.geotoolkit.image.io.metadata.SpatialMetadataFormat#FORMAT_NAME} and

      * {@value javax.imageio.metadata.IIOMetadataFormatImpl#standardMetadataFormatName} formats.

      * The descriptions contain no metadata value, only the name of the nodes together with a few

      * additional information (type, valid values, <i>etc.</i>).

      */

     public void addDefaultMetadataFormats() {

         addMetadataFormat(SpatialMetadataFormat.getStreamInstance(null),

                           SpatialMetadataFormat.getImageInstance (null));

         addMetadataFormat(null, IIOMetadataFormatImpl.getStandardFormatInstance());

     }

 }