/*
 * Jalview - A Sequence Alignment Editor and Viewer ($$Version-Rel$$)
 * Copyright (C) $$Year-Rel$$ The Jalview Authors
 * 
 * This file is part of Jalview.
 * 
 * Jalview 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 3
 * of the License, or (at your option) any later version.
 *  
 * Jalview 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 Jalview.  If not, see <http://www.gnu.org/licenses/>.
 * The Jalview Authors are detailed in the 'AUTHORS' file.
 */
package jalview.io;

import java.io.File;
import java.util.Hashtable;

import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.filechooser.FileView;

public class JalviewFileView extends FileView
{
  static Hashtable<String, String> extensions;

  static void loadExtensions()
  {
    extensions = new Hashtable<String, String>();
    for (FileFormatI ff : FileFormat.values())
    {
      String desc = ff.toString() + " file";
      String exts = ff.getExtensions();
      for (String ext : exts.split(","))
      {
        extensions.put(ext.trim(), desc
                + ("jar".equals(ext) ? " (old)" : ""));
      }
    }
  }

  @Override
  public String getTypeDescription(File f)
  {
    String extension = getExtension(f);
    String type = getDescriptionForExtension(extension);
    if (extension != null)
    {
      if (extensions.containsKey(extension))
      {
        type = extensions.get(extension).toString();
      }
    }

    return type;
  }

  private String getDescriptionForExtension(String extension)
  {
    synchronized (this)
    {
      if (extensions == null)
      {
        loadExtensions();
      }
    }
    return extensions.get(extension);
  }

  @Override
  public Icon getIcon(File f)
  {
    String extension = getExtension(f);
    Icon icon = null;

    if (getDescriptionForExtension(extension) != null)
    {
      icon = createImageIcon("/images/file.png");
    }

    return icon;
  }

  /*
   * Get the extension of a file.
   */
  public static String getExtension(File f)
  {
    String ext = null;
    String s = f.getName();
    int i = s.lastIndexOf('.');

    if ((i > 0) && (i < (s.length() - 1)))
    {
      ext = s.substring(i + 1).toLowerCase();
    }

    return ext;
  }

  /**
   * Returns an ImageIcon, or null if the file was not found
   * 
   * @param filePath
   */
  protected static ImageIcon createImageIcon(String filePath)
  {
    java.net.URL imgURL = JalviewFileView.class.getResource(filePath);

    if (imgURL != null)
    {
      return new ImageIcon(imgURL);
    }
    else
    {
      System.err
              .println("JalviewFileView.createImageIcon: Couldn't find file: "
                      + filePath);

      return null;
    }
  }
}