/**
 *#########################################################################
 *
 * 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.
 *
 * <BR><BR>
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * <BR><BR>
 *
 * Copyright (C) 1999 New Zealand Digital Library Project
 *
 * <BR><BR>
 *
 * 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.
 *
 * <BR><BR>
 *
 * 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.
 *
 * <BR><BR>
 *
 * 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.gui;

import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.File;
import java.io.IOException;
import java.text.*;
import java.util.*;
import javax.swing.*;
import javax.swing.filechooser.*;
import org.greenstone.gatherer.Dictionary;
import org.greenstone.gatherer.collection.BasicCollectionConfiguration;
import org.greenstone.gatherer.collection.CollectionManager;
import org.greenstone.gatherer.util.JarTools;
import org.greenstone.gatherer.util.StaticStrings;
import org.greenstone.gatherer.util.Utility;

public class OpenCollectionDialog
    extends JFileChooser {
    static final private ImageIcon LOCKED_COLLECTION_ICON = JarTools.getImage("lcolicn.gif");
    static final private ImageIcon NORMAL_COLLECTION_ICON = JarTools.getImage("ncolicn.gif");

    /** Constructor */
    public OpenCollectionDialog(File file) {
	super(file);
	///ystem.err.println("Size = " + getSize());
	// Other initialization
	setAcceptAllFileFilterUsed(false);
	setDialogTitle(Dictionary.get("OpenCollectionDialog.Title"));
	setFileFilter(new GathererFilter());
	setFileSystemView(new GathererFileSystemView());
	setFileView(new GathererFileView());
	setSize(400,300);
	// Stop the annoying renaming
	GUIUtils.disableRename(this);
	// Description accessory
	DescriptionPreview accessory = new DescriptionPreview(this);
	setAccessory(accessory);
	// Move accessory
	JPanel accessory_pane = (JPanel) accessory.getParent();
	JPanel center_pane = (JPanel) accessory_pane.getParent();
	center_pane.add(accessory_pane, BorderLayout.SOUTH);
    }

    public void destroy() {
    }

    public String getFileName() {
	// Continually loop until the use chooses an appropriate file or cancels.
	while(true) {
	    int return_val = showOpenDialog(null);
	    if(return_val == JFileChooser.APPROVE_OPTION) {
		File file = getSelectedFile();
		if(file != null && file.getName().endsWith(".col")) {
		    return file.getAbsolutePath();
		}
	    }
	    else {
		return null;
	    }
	}
    }



    /* The DescriptionPreview accessory is adapted from the ImagePreview.java (an example used by FileChooserDemo2.java). */
    private class DescriptionPreview
	extends JPanel
	implements PropertyChangeListener {
	private File file = null;
	private JTextArea text;

	public DescriptionPreview(JFileChooser fc) {
	    setName("Description Preview");
	    setPreferredSize(new Dimension(100, 75)); // About three rows.

	    text = new JTextArea(Dictionary.get("OpenCollectionDialog.No_Description"));
	    
	    setBorder(BorderFactory.createEmptyBorder(5,0,0,0));
	    setLayout(new BorderLayout());
	    add(new JScrollPane(text), BorderLayout.CENTER);

	    fc.addPropertyChangeListener(this);
	}

	/** Whenever a new file or folder is selected we determine what description should be displayed. */
	public void propertyChange(PropertyChangeEvent e) {
	    boolean update = false;
	    String prop = e.getPropertyName();
	    // If the directory changed, don't show an image.
	    if (JFileChooser.DIRECTORY_CHANGED_PROPERTY.equals(prop)) {
		file = null;
		update = true;
	    }
	    // If a file became selected, find out which one.
	    else if (JFileChooser.SELECTED_FILE_CHANGED_PROPERTY.equals(prop)) {
		file = (File) e.getNewValue();
		update = true;
	    }

	    // Update the description accordingly.
	    if (update) {
		if(file == null) {
		    text.setText(Dictionary.get("OpenCollectionDialog.No_Description"));
		}
		else {
		    // Build a wrapper around the collection configuration file.
		    File config_file = new File(file.getParentFile(), Utility.CONFIG_FILE);
		    if(config_file.exists()) {
			BasicCollectionConfiguration collect_cfg = new BasicCollectionConfiguration(config_file);
			text.setText(StaticStrings.SPEECH_CHARACTER + collect_cfg.getName() + StaticStrings.SPEECH_CHARACTER + StaticStrings.NEW_LINE_CHAR);
			text.setText(collect_cfg.getDescription());
			text.setCaretPosition(0);
		    }
		}
	    }
	}
    }

    /** ImageFilter.java is a 1.4 example used by FileChooserDemo2.java. */
    private class GathererFilter
	extends FileFilter {

	// Accept all directories and all .col files
	public boolean accept(File f) {
	    return (f.isDirectory() || f.getName().toLowerCase().endsWith(".col"));
	}

	// The description of this filter
	public String getDescription() {
	    return Dictionary.get("OpenCollectionDialog.Collection");
	}
    }

    private class GathererFileSystemView
	extends FileSystemView {

	private FileSystemView default_system_view = FileSystemView.getFileSystemView();

	/** Creates a new folder with a default folder name. */
	public File createNewFolder(File containingDir)
	    throws IOException {
	    return default_system_view.createNewFolder(containingDir);
	}

	/** Gets the list of shown (i.e. */
	public File[] getFiles(File dir, boolean useFileHiding) {
	    // Retrieve the files usually returned by the platform specific file system view.
	    File[] files = default_system_view.getFiles(dir, useFileHiding);
	    // Determine if the current dir actually contains a valid greenstone collection. To do this we check for the presence of the file <dir>/etc/collect.cfg and a directory named import.
	    File collect_cfg_file = new File(dir, Utility.CONFIG_FILE);
	    File import_dir_file = new File(dir, "import");
	    if(collect_cfg_file.exists() && import_dir_file.exists()) {
		// Create a new dummy collection file.
		String name = dir.getName();
		File collection_file = new File(dir, name + ".col");
		// If this file doesn't already exist.
		if(!collection_file.exists()) {
		    File[] temp = new File[files.length + 1];
		    System.arraycopy(files, 0, temp, 0, files.length);
		    temp[files.length] = collection_file;
		    files = temp;
		    temp = null;
		}
		collection_file = null;
		name = null;
	    }
	    import_dir_file = null;
	    collect_cfg_file = null;
	    return files;
	}
    }

    /** A FileView which returns differing icons depending on whether a lock file is present within the collection folder. */
    private class GathererFileView
	extends FileView {

	public String getDescription(File file) {
	    String description = null;
	    if (file.getName().endsWith(".col")) {
		if (!lockExists(file)) {
		    description = Dictionary.get("OpenCollectionDialog.Normal_Collection");
		}
		else {
		    description = Dictionary.get("OpenCollectionDialog.Locked_Collection");
		}
	    }
	    return description;
	}

	public Icon getIcon(File file) {
	    Icon icon = null;
	    if (file.getName().endsWith(".col")) {
		if (!lockExists(file)) {
		    icon = NORMAL_COLLECTION_ICON;
		}
		else {
		    icon = LOCKED_COLLECTION_ICON;
		}
	    }
	    return icon;
	}

	/** Determine if a lock file exists. */
	private boolean lockExists(File file) {
	    File lock_file = new File(file.getParentFile(), CollectionManager.LOCK_FILE);
	    return lock_file.exists();
	}
    }
}