/*
    * $HeadURL: https://svn.apache.org/repos/asf/httpcomponents/oac.hc3x/trunk/src/java/org/apache/commons/httpclient/methods/multipart/FilePart.java $
    * $Revision: 1425331 $
    * $Date: 2012-12-22 18:29:41 +0000 (Sat, 22 Dec 2012) $
    *
    * ====================================================================
    *
    *  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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  
  package org.apache.commons.httpclient.methods.multipart;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import org.apache.commons.httpclient.util.EncodingUtil;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  /***
   * This class implements a part of a Multipart post object that
   * consists of a file.  
   *
   * @author <a href="mailto:mattalbright@yahoo.com">Matthew Albright</a>
   * @author <a href="mailto:jsdever@apache.org">Jeff Dever</a>
   * @author <a href="mailto:adrian@ephox.com">Adrian Sutton</a>
   * @author <a href="mailto:becke@u.washington.edu">Michael Becke</a>
   * @author <a href="mailto:mdiggory@latte.harvard.edu">Mark Diggory</a>
   * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
   * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
   *   
   * @since 2.0 
   *
   */
  public class FilePart extends PartBase {
  
      /*** Default content encoding of file attachments. */
      public static final String DEFAULT_CONTENT_TYPE = "application/octet-stream";
  
      /*** Default charset of file attachments. */
      public static final String DEFAULT_CHARSET = "ISO-8859-1";
  
      /*** Default transfer encoding of file attachments. */
      public static final String DEFAULT_TRANSFER_ENCODING = "binary";
  
      /*** Log object for this class. */
      private static final Log LOG = LogFactory.getLog(FilePart.class);
  
      /*** Attachment's file name */
      protected static final String FILE_NAME = "; filename=";
  
      /*** Attachment's file name as a byte array */
      private static final byte[] FILE_NAME_BYTES = 
          EncodingUtil.getAsciiBytes(FILE_NAME);
  
      /*** Source of the file part. */
      private PartSource source;
  
      /***
       * FilePart Constructor.
       *
       * @param name the name for this part
       * @param partSource the source for this part
       * @param contentType the content type for this part, if <code>null</code> the 
       * {@link #DEFAULT_CONTENT_TYPE default} is used
       * @param charset the charset encoding for this part, if <code>null</code> the 
       * {@link #DEFAULT_CHARSET default} is used
       */
      public FilePart(String name, PartSource partSource, String contentType, String charset) {
          
          super(
              name, 
              contentType == null ? DEFAULT_CONTENT_TYPE : contentType, 
              charset == null ? "ISO-8859-1" : charset, 
              DEFAULT_TRANSFER_ENCODING
          );
  
         if (partSource == null) {
             throw new IllegalArgumentException("Source may not be null");
         }
         this.source = partSource;
     }
         
     /***
      * FilePart Constructor.
      *
      * @param name the name for this part
      * @param partSource the source for this part
      */
     public FilePart(String name, PartSource partSource) {
         this(name, partSource, null, null);
     }
 
     /***
      * FilePart Constructor.
      *
      * @param name the name of the file part
      * @param file the file to post
      *
      * @throws FileNotFoundException if the <i>file</i> is not a normal
      * file or if it is not readable.
      */
     public FilePart(String name, File file) 
     throws FileNotFoundException {
         this(name, new FilePartSource(file), null, null);
     }
 
     /***
      * FilePart Constructor.
      *
      * @param name the name of the file part
      * @param file the file to post
      * @param contentType the content type for this part, if <code>null</code> the 
      * {@link #DEFAULT_CONTENT_TYPE default} is used
      * @param charset the charset encoding for this part, if <code>null</code> the 
      * {@link #DEFAULT_CHARSET default} is used
      *
      * @throws FileNotFoundException if the <i>file</i> is not a normal
      * file or if it is not readable.
      */
     public FilePart(String name, File file, String contentType, String charset) 
     throws FileNotFoundException {
         this(name, new FilePartSource(file), contentType, charset);
     }
 
      /***
      * FilePart Constructor.
      *
      * @param name the name of the file part
      * @param fileName the file name 
      * @param file the file to post
      *
      * @throws FileNotFoundException if the <i>file</i> is not a normal
      * file or if it is not readable.
      */
     public FilePart(String name, String fileName, File file) 
     throws FileNotFoundException {
         this(name, new FilePartSource(fileName, file), null, null);
     }
     
      /***
      * FilePart Constructor.
      *
      * @param name the name of the file part
      * @param fileName the file name 
      * @param file the file to post
      * @param contentType the content type for this part, if <code>null</code> the 
      * {@link #DEFAULT_CONTENT_TYPE default} is used
      * @param charset the charset encoding for this part, if <code>null</code> the 
      * {@link #DEFAULT_CHARSET default} is used
      *
      * @throws FileNotFoundException if the <i>file</i> is not a normal
      * file or if it is not readable.
      */
     public FilePart(String name, String fileName, File file, String contentType, String charset) 
     throws FileNotFoundException {
         this(name, new FilePartSource(fileName, file), contentType, charset);
     }
     
     /***
      * Write the disposition header to the output stream
      * @param out The output stream
      * @throws IOException If an IO problem occurs
      * @see Part#sendDispositionHeader(OutputStream)
      */
     protected void sendDispositionHeader(OutputStream out) 
     throws IOException {
         LOG.trace("enter sendDispositionHeader(OutputStream out)");
         super.sendDispositionHeader(out);
         String filename = this.source.getFileName();
         if (filename != null) {
             out.write(FILE_NAME_BYTES);
             out.write(QUOTE_BYTES);
             out.write(EncodingUtil.getAsciiBytes(filename));
             out.write(QUOTE_BYTES);
         }
     }
     
     /***
      * Write the data in "source" to the specified stream.
      * @param out The output stream.
      * @throws IOException if an IO problem occurs.
      * @see org.apache.commons.httpclient.methods.multipart.Part#sendData(OutputStream)
      */
     protected void sendData(OutputStream out) throws IOException {
         LOG.trace("enter sendData(OutputStream out)");
         if (lengthOfData() == 0) {
             
             // this file contains no data, so there is nothing to send.
             // we don't want to create a zero length buffer as this will
             // cause an infinite loop when reading.
             LOG.debug("No data to send.");
             return;
         }
         
         byte[] tmp = new byte[4096];
         InputStream instream = source.createInputStream();
         try {
             int len;
             while ((len = instream.read(tmp)) >= 0) {
                 out.write(tmp, 0, len);
             }
         } finally {
             // we're done with the stream, close it
             instream.close();
         }
     }
 
     /*** 
      * Returns the source of the file part.
      *  
      * @return The source.
      */
     protected PartSource getSource() {
         LOG.trace("enter getSource()");
         return this.source;
     }
 
     /***
      * Return the length of the data.
      * @return The length.
      * @throws IOException if an IO problem occurs
      * @see org.apache.commons.httpclient.methods.multipart.Part#lengthOfData()
      */    
     protected long lengthOfData() throws IOException {
         LOG.trace("enter lengthOfData()");
         return source.getLength();
     }    
 
 }