/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.tools.example.debug.gui;

import java.io.File;

import java.util.Hashtable;

import java.util.Enumeration;

import javax.swing.*;

import javax.swing.filechooser.*;

//### Renamed from 'ExampleFileFilter.java' provided with Swing demos.

/**

 * A convenience implementation of FileFilter that filters out

 * all files except for those type extensions that it knows about.

 *

 * Extensions are of the type ".foo", which is typically found on

 * Windows and Unix boxes, but not on Macinthosh. Case is ignored.

 *

 * Example - create a new filter that filerts out all files

 * but gif and jpg image files:

 *

 *     JFileChooser chooser = new JFileChooser();

 *     ExampleFileFilter filter = new ExampleFileFilter(

 *                   new String{"gif", "jpg"}, "JPEG & GIF Images")

 *     chooser.addChoosableFileFilter(filter);

 *     chooser.showOpenDialog(this);

 *

 * @author Jeff Dinkins

 */

public class JDBFileFilter extends FileFilter {

    private static String TYPE_UNKNOWN = "Type Unknown";

    private static String HIDDEN_FILE = "Hidden File";

    private Hashtable<String, JDBFileFilter> filters = null;

    private String description = null;

    private String fullDescription = null;

    private boolean useExtensionsInDescription = true;

    /**

     * Creates a file filter. If no filters are added, then all

     * files are accepted.

     *

     * @see #addExtension

     */

    public JDBFileFilter() {

        this.filters = new Hashtable<String, JDBFileFilter>();

    }

    /**

     * Creates a file filter that accepts files with the given extension.

     * Example: new JDBFileFilter("jpg");

     *

     * @see #addExtension

     */

    public JDBFileFilter(String extension) {

        this(extension,null);

    }

    /**

     * Creates a file filter that accepts the given file type.

     * Example: new JDBFileFilter("jpg", "JPEG Image Images");

     *

     * Note that the "." before the extension is not needed. If

     * provided, it will be ignored.

     *

     * @see #addExtension

     */

    public JDBFileFilter(String extension, String description) {

        this();

        if(extension!=null) addExtension(extension);

        if(description!=null) setDescription(description);

    }

    /**

     * Creates a file filter from the given string array.

     * Example: new JDBFileFilter(String {"gif", "jpg"});

     *

     * Note that the "." before the extension is not needed adn

     * will be ignored.

     *

     * @see #addExtension

     */

    public JDBFileFilter(String[] filters) {

        this(filters, null);

    }

    /**

     * Creates a file filter from the given string array and description.

     * Example: new JDBFileFilter(String {"gif", "jpg"}, "Gif and JPG Images");

     *

     * Note that the "." before the extension is not needed and will be ignored.

     *

     * @see #addExtension

     */

    public JDBFileFilter(String[] filters, String description) {

        this();

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

            // add filters one by one

            addExtension(filters[i]);

        }

        if(description!=null) setDescription(description);

    }

    /**

     * Return true if this file should be shown in the directory pane,

     * false if it shouldn't.

     *

     * Files that begin with "." are ignored.

     *

     * @see #getExtension

     * @see FileFilter#accepts

     */

    public boolean accept(File f) {

        if(f != null) {

            if(f.isDirectory()) {

                return true;

            }

            String extension = getExtension(f);

            if(extension != null && filters.get(getExtension(f)) != null) {

                return true;

            };

        }

        return false;

    }

    /**

     * Return the extension portion of the file's name .

     *

     * @see #getExtension

     * @see FileFilter#accept

     */

     public String getExtension(File f) {

        if(f != null) {

            String filename = f.getName();

            int i = filename.lastIndexOf('.');

            if(i>0 && i<filename.length()-1) {

                return filename.substring(i+1).toLowerCase();

            };

        }

        return null;

    }

    /**

     * Adds a filetype "dot" extension to filter against.

     *

     * For example: the following code will create a filter that filters

     * out all files except those that end in ".jpg" and ".tif":

     *

     *   JDBFileFilter filter = new JDBFileFilter();

     *   filter.addExtension("jpg");

     *   filter.addExtension("tif");

     *

     * Note that the "." before the extension is not needed and will be ignored.

     */

    public void addExtension(String extension) {

        if(filters == null) {

            filters = new Hashtable<String, JDBFileFilter>(5);

        }

        filters.put(extension.toLowerCase(), this);

        fullDescription = null;

    }

    /**

     * Returns the human readable description of this filter. For

     * example: "JPEG and GIF Image Files (*.jpg, *.gif)"

     *

     * @see setDescription

     * @see setExtensionListInDescription

     * @see isExtensionListInDescription

     * @see FileFilter#getDescription

     */

    public String getDescription() {

        if(fullDescription == null) {

            if(description == null || isExtensionListInDescription()) {

                fullDescription = description==null ? "(" : description + " (";

                // build the description from the extension list

                Enumeration<String> extensions = filters.keys();

                if(extensions != null) {

                    fullDescription += "." + extensions.nextElement();

                    while (extensions.hasMoreElements()) {

                        fullDescription += ", " + extensions.nextElement();

                    }

                }

                fullDescription += ")";

            } else {

                fullDescription = description;

            }

        }

        return fullDescription;

    }

    /**

     * Sets the human readable description of this filter. For

     * example: filter.setDescription("Gif and JPG Images");

     *

     * @see setDescription

     * @see setExtensionListInDescription

     * @see isExtensionListInDescription

     */

    public void setDescription(String description) {

        this.description = description;

        fullDescription = null;

    }

    /**

     * Determines whether the extension list (.jpg, .gif, etc) should

     * show up in the human readable description.

     *

     * Only relevent if a description was provided in the constructor

     * or using setDescription();

     *

     * @see getDescription

     * @see setDescription

     * @see isExtensionListInDescription

     */

    public void setExtensionListInDescription(boolean b) {

        useExtensionsInDescription = b;

        fullDescription = null;

    }

    /**

     * Returns whether the extension list (.jpg, .gif, etc) should

     * show up in the human readable description.

     *

     * Only relevent if a description was provided in the constructor

     * or using setDescription();

     *

     * @see getDescription

     * @see setDescription

     * @see setExtensionListInDescription

     */

    public boolean isExtensionListInDescription() {

        return useExtensionsInDescription;

    }

}