/*
 * $Id: FTPURLConnection.java,v 1.7 2004/07/30 20:56:02 dog Exp $
 * Copyright (C) 2003 The Free Software Foundation
 * 
 * This file is part of GNU inetlib, a library.
 * 
 * GNU inetlib 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.
 * 
 * GNU inetlib 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 * As a special exception, if you link this library with other files to
 * produce an executable, this library does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * This exception does not however invalidate any other reasons why the
 * executable file might be covered by the GNU General Public License.
 */

package gnu.inet.ftp;

import java.io.FileNotFoundException;
import java.io.FilterInputStream;
import java.io.FilterOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.URL;
import java.net.URLConnection;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.HashMap;
import java.util.Map;

import gnu.inet.util.GetLocalHostAction;
import gnu.inet.util.GetSystemPropertyAction;

/**
 * An FTP URL connection.
 *
 * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
 * @version $Revision: 1.7 $ $Date: 2004/07/30 20:56:02 $
 */
public class FTPURLConnection extends URLConnection
{

  /**
   * The connection managing the protocol exchange.
   */
  protected FTPConnection connection;

  protected boolean passive;
  protected int representationType;
  protected int fileStructure;
  protected int transferMode;

  /**
   * Constructs an FTP connection to the specified URL.
   * @param url the URL
   */
  public FTPURLConnection (URL url)
  {
    super (url);
    passive = true;
    representationType = FTPConnection.TYPE_BINARY;
    fileStructure = -1;
    transferMode = -1;
  }

  /**
   * Establishes the connection.
   */
  public void connect () throws IOException
  {
    if (connected)
      {
        return;
      }
    String host = url.getHost ();
    int port = url.getPort ();
    String username = url.getUserInfo ();
    String password = null;
    if (username != null)
      {
        int ci = username.indexOf (':');
        if (ci != -1)
          {
            password = username.substring (ci + 1);
            username = username.substring (0, ci);
          }
      }
    else
      {
        username = "anonymous";
        PrivilegedAction a = new GetSystemPropertyAction ("user.name");
        String systemUsername = (String) AccessController.doPrivileged (a);
        a = new GetLocalHostAction ();
        InetAddress localhost = (InetAddress) AccessController.doPrivileged (a);
        password = systemUsername + "@" +
          ((localhost == null) ? "localhost" : localhost.getHostName ());
      }
    connection = new FTPConnection (host, port);
    if (!connection.authenticate (username, password))
      {
        throw new SecurityException ("Authentication failed");
      }
    connection.setPassive (passive);
    if (representationType != -1)
      {
        connection.setRepresentationType (representationType);
      }
    if (fileStructure != -1)
      {
        connection.setFileStructure (fileStructure);
      }
    if (transferMode != -1)
      {
        connection.setTransferMode (transferMode);
      }
  }
  
  /**
   * This connection supports doInput.
   */
  public void setDoInput (boolean doinput)
  {
    doInput = doinput;
  }

  /**
   * This connection supports doOutput.
   */
  public void setDoOutput (boolean dooutput)
  {
    doOutput = dooutput;
  }
  
  /**
   * Returns an input stream that reads from this open connection.
   */
  public InputStream getInputStream () throws IOException
  {
    if (!connected)
      {
        connect ();
      }
    String path = url.getPath ();
    String filename = null;
    int lsi = path.lastIndexOf ('/');
    if (lsi != -1)
      {
        filename = path.substring (lsi + 1);
        path = path.substring (0, lsi);
        if (!connection.changeWorkingDirectory (path))
          {
            throw new FileNotFoundException (path);
          }
      }
    if (filename != null && filename.length () > 0)
      {
        return this.new ClosingInputStream (connection.retrieve (filename));
      }
    else
      {
        return this.new ClosingInputStream (connection.list (null));
      }
  }
  
  /**
   * Returns an output stream that writes to this connection.
   */
  public OutputStream getOutputStream () throws IOException
  {
    if (!connected)
      {
        connect ();
      }
    String dir = url.getPath ();
    String filename = url.getFile ();
    if (!connection.changeWorkingDirectory (dir))
      {
        throw new FileNotFoundException (dir);
      }
    if (filename != null)
      {
        return this.new ClosingOutputStream (connection.store (filename));
      }
    else
      {
        throw new FileNotFoundException (filename);
      }
  }

  public String getRequestProperty (String key)
  {
    if ("passive".equals (key))
      {
        return Boolean.toString (passive);
      }
    else if ("representationType".equals (key))
      {
        switch (representationType)
          {
          case FTPConnection.TYPE_ASCII:
            return "ASCII";
          case FTPConnection.TYPE_EBCDIC:
            return "EBCDIC";
          case FTPConnection.TYPE_BINARY:
            return "BINARY";
          }
      }
    else if ("fileStructure".equals (key))
      {
        switch (fileStructure)
          {
          case FTPConnection.STRUCTURE_FILE:
            return "FILE";
          case FTPConnection.STRUCTURE_RECORD:
            return "RECORD";
          case FTPConnection.STRUCTURE_PAGE:
            return "PAGE";
          }
      }
    else if ("transferMode".equals (key))
      {
        switch (transferMode)
          {
          case FTPConnection.MODE_STREAM:
            return "STREAM";
          case FTPConnection.MODE_BLOCK:
            return "BLOCK";
          case FTPConnection.MODE_COMPRESSED:
            return "COMPRESSED";
          }
      }
    return null;
  }

  public Map getRequestProperties ()
  {
    Map map = new HashMap ();
    addRequestPropertyValue (map, "passive");
    addRequestPropertyValue (map, "representationType");
    addRequestPropertyValue (map, "fileStructure");
    addRequestPropertyValue (map, "transferMode");
    return map;
  }

  private void addRequestPropertyValue (Map map, String key)
  {
    String value = getRequestProperty (key);
    map.put (key, value);
  }
  
  public void setRequestProperty (String key, String value)
  {
    if (connected)
      {
        throw new IllegalStateException ();
      }
    if ("passive".equals (key))
      {
        passive = Boolean.valueOf (value).booleanValue ();
      }
    else if ("representationType".equals (key))
      {
        if ("A".equalsIgnoreCase (value) ||
            "ASCII".equalsIgnoreCase (value))
          {
            representationType = FTPConnection.TYPE_ASCII;
          }
        else if ("E".equalsIgnoreCase (value) ||
                 "EBCDIC".equalsIgnoreCase (value))
          {
            representationType = FTPConnection.TYPE_EBCDIC;
          }
        else if ("I".equalsIgnoreCase (value) ||
                 "BINARY".equalsIgnoreCase (value))
          {
            representationType = FTPConnection.TYPE_BINARY;
          }
        else
          {
            throw new IllegalArgumentException (value);
          }
      }
    else if ("fileStructure".equals (key))
      {
        if ("F".equalsIgnoreCase (value) ||
            "FILE".equalsIgnoreCase (value))
          {
            fileStructure = FTPConnection.STRUCTURE_FILE;
          }
        else if ("R".equalsIgnoreCase (value) ||
                 "RECORD".equalsIgnoreCase (value))
          {
            fileStructure = FTPConnection.STRUCTURE_RECORD;
          }
        else if ("P".equalsIgnoreCase (value) ||
                 "PAGE".equalsIgnoreCase (value))
          {
            fileStructure = FTPConnection.STRUCTURE_PAGE;
          }
        else
          {
            throw new IllegalArgumentException (value);
          }
      }
    else if ("transferMode".equals (key))
      {
        if ("S".equalsIgnoreCase (value) ||
            "STREAM".equalsIgnoreCase (value))
          {
            transferMode = FTPConnection.MODE_STREAM;
          }
        else if ("B".equalsIgnoreCase (value) ||
                 "BLOCK".equalsIgnoreCase (value))
          {
            transferMode = FTPConnection.MODE_BLOCK;
          }
        else if ("C".equalsIgnoreCase (value) ||
                 "COMPRESSED".equalsIgnoreCase (value))
          {
            transferMode = FTPConnection.MODE_COMPRESSED;
          }
        else
          {
            throw new IllegalArgumentException (value);
          }
      }
  }

  public void addRequestProperty (String key, String value)
  {
    setRequestProperty (key, value);
  }

  class ClosingInputStream
    extends FilterInputStream
  {

    ClosingInputStream (InputStream in)
    {
      super (in);
    }

    public void close ()
      throws IOException
    {
      super.close ();
      connection.logout ();
    }
    
  }

  class ClosingOutputStream
    extends FilterOutputStream
  {

    ClosingOutputStream (OutputStream out)
    {
      super (out);
    }

    public void close ()
      throws IOException
    {
      super.close ();
      connection.logout ();
    }
    
  }

}
