// ========================================================================
   // Copyright (c) 1996-2009 Mort Bay Consulting Pty. Ltd.
   // ------------------------------------------------------------------------
   // All rights reserved. This program and the accompanying materials
   // are made available under the terms of the Eclipse Public License v1.0
   // and Apache License v2.0 which accompanies this distribution.
   // The Eclipse Public License is available at 
   // http://www.eclipse.org/legal/epl-v10.html
   // The Apache License v2.0 is available at
  // http://www.opensource.org/licenses/apache2.0.php
  // You may elect to redistribute this code under either of these licenses. 
  // ========================================================================
  package org.eclipse.jetty.util.resource;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.FilterInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.JarURLConnection;
  import java.net.URL;
  import java.util.jar.JarEntry;
  import java.util.jar.JarInputStream;
  import java.util.jar.Manifest;
  
  import org.eclipse.jetty.util.IO;
  import org.eclipse.jetty.util.URIUtil;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  
  
  /* ------------------------------------------------------------ */
  public class JarResource extends URLResource
  {
      private static final Logger LOG = Log.getLogger(JarResource.class);
      protected JarURLConnection _jarConnection;
      
      /* -------------------------------------------------------- */
      JarResource(URL url)
      {
          super(url,null);
      }
  
      /* ------------------------------------------------------------ */
      JarResource(URL url, boolean useCaches)
      {
          super(url, null, useCaches);
      }
      
      /* ------------------------------------------------------------ */
      @Override
      public synchronized void release()
      {
          _jarConnection=null;
          super.release();
      }
      
      /* ------------------------------------------------------------ */
      @Override
      protected synchronized boolean checkConnection()
      {
          super.checkConnection();
          try
          {
              if (_jarConnection!=_connection)
                  newConnection();
          }
          catch(IOException e)
          {
              LOG.ignore(e);
              _jarConnection=null;
          }
          
          return _jarConnection!=null;
      }
  
      /* ------------------------------------------------------------ */
      /**
       * @throws IOException Sub-classes of <code>JarResource</code> may throw an IOException (or subclass) 
       */
      protected void newConnection() throws IOException
      {
          _jarConnection=(JarURLConnection)_connection;
      }
      
      /* ------------------------------------------------------------ */
      /**
       * Returns true if the respresenetd resource exists.
       */
      @Override
      public boolean exists()
      {
          if (_urlString.endsWith("!/"))
              return checkConnection();
          else
              return super.exists();
      }    
  
      /* ------------------------------------------------------------ */
     @Override
     public File getFile()
         throws IOException
     {
         return null;
     }
     
     /* ------------------------------------------------------------ */
     @Override
     public InputStream getInputStream()
         throws java.io.IOException
     {     
         checkConnection();
         if (!_urlString.endsWith("!/"))
             return new FilterInputStream(super.getInputStream()) 
             {
                 @Override
                 public void close() throws IOException {this.in=IO.getClosedStream();}
             };
 
         URL url = new URL(_urlString.substring(4,_urlString.length()-2));      
         InputStream is = url.openStream();
         return is;
     }
     
     /* ------------------------------------------------------------ */
     @Override
     public void copyTo(File directory)
         throws IOException
     {
         if (!exists())
             return;
         
         if(LOG.isDebugEnabled())
             LOG.debug("Extract "+this+" to "+directory);
         
         String urlString = this.getURL().toExternalForm().trim();
         int endOfJarUrl = urlString.indexOf("!/");
         int startOfJarUrl = (endOfJarUrl >= 0?4:0);
         
         if (endOfJarUrl < 0)
             throw new IOException("Not a valid jar url: "+urlString);
         
         URL jarFileURL = new URL(urlString.substring(startOfJarUrl, endOfJarUrl));
         String subEntryName = (endOfJarUrl+2 < urlString.length() ? urlString.substring(endOfJarUrl + 2) : null);
         boolean subEntryIsDir = (subEntryName != null && subEntryName.endsWith("/")?true:false);
       
         if (LOG.isDebugEnabled()) 
             LOG.debug("Extracting entry = "+subEntryName+" from jar "+jarFileURL);
         
         InputStream is = jarFileURL.openConnection().getInputStream();
         JarInputStream jin = new JarInputStream(is);
         JarEntry entry;
         boolean shouldExtract;
         while((entry=jin.getNextJarEntry())!=null)
         {
             String entryName = entry.getName();
             if ((subEntryName != null) && (entryName.startsWith(subEntryName)))
             { 
                 // is the subentry really a dir?
                 if (!subEntryIsDir && subEntryName.length()+1==entryName.length() && entryName.endsWith("/"))
                         subEntryIsDir=true;
                 
                 //if there is a particular subEntry that we are looking for, only
                 //extract it.
                 if (subEntryIsDir)
                 {
                     //if it is a subdirectory we are looking for, then we
                     //are looking to extract its contents into the target
                     //directory. Remove the name of the subdirectory so
                     //that we don't wind up creating it too.
                     entryName = entryName.substring(subEntryName.length());
                     if (!entryName.equals(""))
                     {
                         //the entry is 
                         shouldExtract = true;                   
                     }
                     else
                         shouldExtract = false;
                 }
                 else
                     shouldExtract = true;
             }
             else if ((subEntryName != null) && (!entryName.startsWith(subEntryName)))
             {
                 //there is a particular entry we are looking for, and this one
                 //isn't it
                 shouldExtract = false;
             }
             else
             {
                 //we are extracting everything
                 shouldExtract =  true;
             }
                 
             
             if (!shouldExtract)
             {
                 if (LOG.isDebugEnabled()) 
                     LOG.debug("Skipping entry: "+entryName);
                 continue;
             }
                 
             String dotCheck = entryName.replace('\\', '/');   
             dotCheck = URIUtil.canonicalPath(dotCheck);
             if (dotCheck == null)
             {
                 if (LOG.isDebugEnabled()) 
                     LOG.debug("Invalid entry: "+entryName);
                 continue;
             }
 
             File file=new File(directory,entryName);
      
             if (entry.isDirectory())
             {
                 // Make directory
                 if (!file.exists())
                     file.mkdirs();
             }
             else
             {
                 // make directory (some jars don't list dirs)
                 File dir = new File(file.getParent());
                 if (!dir.exists())
                     dir.mkdirs();
 
                 // Make file
                 FileOutputStream fout = null;
                 try
                 {
                     fout = new FileOutputStream(file);
                     IO.copy(jin,fout);
                 }
                 finally
                 {
                     IO.close(fout);
                 }
 
                 // touch the file.
                 if (entry.getTime()>=0)
                     file.setLastModified(entry.getTime());
             }
         }
         
         if ((subEntryName == null) || (subEntryName != null && subEntryName.equalsIgnoreCase("META-INF/MANIFEST.MF")))
         {
             Manifest manifest = jin.getManifest();
             if (manifest != null)
             {
                 File metaInf = new File (directory, "META-INF");
                 metaInf.mkdir();
                 File f = new File(metaInf, "MANIFEST.MF");
                 FileOutputStream fout = new FileOutputStream(f);
                 manifest.write(fout);
                 fout.close();   
             }
         }
         IO.close(jin);
     }   
     
     public static Resource newJarResource(Resource resource) throws IOException
     {
         if (resource instanceof JarResource)
             return resource;
         return Resource.newResource("jar:" + resource + "!/");
     }
 }