/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    * 
    *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.jetspeed.util;
  
  import java.io.File;
  import java.io.FileFilter;
  import java.io.FileNotFoundException;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.util.Enumeration;
  import java.util.jar.JarEntry;
  import java.util.jar.JarFile;
  
  /***
   * @author <a href="mailto:weaver@apache.org">Scott T. Weaver </a>
   * 
   * Creates a a temp directory to which a JarFile is expanded and can be
   * manipulated. All operations are performed by an internal instance of
   * {@link DirectoryHelper}.
   *  
   */
  public class JarHelper 
      extends
          AbstractFileSystemHelper
      implements 
          FileSystemHelper
  {
      protected JarFile jarFile;
      protected DirectoryHelper dirHelper;
      protected File file;
      private boolean deleteOnClose;
      protected File jarRoot;
  
      /***
       * 
       * @param jarFile
       * @throws IOException
       */
      public JarHelper( File file, boolean deleteOnClose ) throws IOException
      {
          this.jarFile = new JarFile(file);
          this.deleteOnClose = deleteOnClose;
          this.file = file;
          String tmpDirPath = System.getProperty("java.io.tmpdir");
          File tmpDir = new File(tmpDirPath);
          jarRoot = null;
  
          jarRoot = new File(tmpDir, "jetspeed-jar-tmp/" + file.getName());
  
          if (!jarRoot.exists())
          {
              jarRoot.mkdirs();
          }
          jarRoot.deleteOnExit();
  
          Enumeration entries = this.jarFile.entries();
          while (entries.hasMoreElements())
          {
              JarEntry jarEntry = (JarEntry) entries.nextElement();
              String name = jarEntry.getName();
              if (jarEntry.isDirectory())
              {
                  File newDir = new File(jarRoot, name);
                  newDir.mkdir();
                  newDir.deleteOnExit();
              }
              else
              {
                  copyEntryToFile(jarFile, jarRoot, jarEntry);
              }
          }
  
          dirHelper = new DirectoryHelper(jarRoot);
      }
  
      /***
       * <p>
       * copyEntryToFile
       * </p>
       * 
       * @param jarFile
       * @param jarRoot
       * @param jarEntry
      * @throws IOException
      * @throws FileNotFoundException
      */
     protected void copyEntryToFile( JarFile jarFile, File jarRoot, JarEntry jarEntry ) throws IOException,
             FileNotFoundException
     {
         String name = jarEntry.getName();
         File file = new File(jarRoot, name);
         if (!file.getParentFile().exists())
         {
             file.getParentFile().mkdirs();
             file.getParentFile().deleteOnExit();
         }
         file.createNewFile();
         file.deleteOnExit();
 
         InputStream is = null;
         OutputStream os = null;
         try
         {
             is = jarFile.getInputStream(jarEntry);
             os = new FileOutputStream(file);
 
             byte[] buf = new byte[1024];
             int len;
             while ((len = is.read(buf)) > 0)
             {
                 os.write(buf, 0, len);
             }
 
         }
         finally
         {
             if (is != null)
             {
                 is.close();
             }
 
             if (os != null)
             {
                 os.close();
             }
         }
     }
 
     /***
      * <p>
      * copyFrom
      * </p>
      *
      * @param directory
      * @param fileFilter
      * @throws IOException
      */
     public void copyFrom( File directory, FileFilter fileFilter ) throws IOException
     {
         dirHelper.copyFrom(directory, fileFilter);
     }
     /***
      * <p>
      * copyFrom
      * </p>
      * 
      * @see org.apache.jetspeed.util.FileSystemHelper#copyFrom(java.io.File)
      * @param directory
      * @throws IOException
      */
     public void copyFrom( File directory ) throws IOException
     {
         dirHelper.copyFrom(directory);
     }
 
     /***
      * <p>
      * getRootDirectory
      * </p>
      * 
      * @see org.apache.jetspeed.util.FileSystemHelper#getRootDirectory()
      * @return
      */
     public File getRootDirectory()
     {
         return dirHelper.getRootDirectory();
     }
 
     /***
      * <p>
      * remove
      * </p>
      * 
      * @see org.apache.jetspeed.util.FileSystemHelper#remove()
      * @return
      */
     public boolean remove()
     {
         return dirHelper.remove();
     }
 
     /***
      * <p>
      * close
      * </p>
      * 
      * @throws IOException
      * 
      * @see org.apache.jetspeed.util.FileSystemHelper#close()
      *  
      */
     public void close() throws IOException
     {
         jarFile.close();
         if (deleteOnClose)
         {
             // remove all temporary files
             dirHelper.remove();
         }
         
         dirHelper.close();
     }
 
     /***
      * <p>
      * getSourcePath
      * </p>
      * 
      * @see org.apache.jetspeed.util.FileSystemHelper#getSourcePath()
      * @return
      */
     public String getSourcePath()
     {
         return file.getAbsolutePath();
     }
 }