/************************************************************************
    * Copyright (c) 2000-2006 The Apache Software Foundation.             *
    * All rights reserved.                                                *
    * ------------------------------------------------------------------- *
    * Licensed 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.james.core;
  
  import javax.mail.MessagingException;
  import javax.mail.util.SharedFileInputStream;
  
  import java.io.BufferedOutputStream;
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  
  import org.apache.avalon.framework.activity.Disposable;
  
  /***
   * Takes an input stream and creates a repeatable input stream source
   * for a MimeMessageWrapper.  It does this by completely reading the
   * input stream and saving that to a temporary file that should delete on exit,
   * or when this object is GC'd.
   *
   * @see MimeMessageWrapper
   *
   *
   */
  public class MimeMessageInputStreamSource
      extends MimeMessageSource
      implements Disposable {
  
      /***
       * A temporary file used to hold the message stream
       */
      File file;
  
      /***
       * The full path of the temporary file
       */
      String sourceId;
  
      /***
       * Construct a new MimeMessageInputStreamSource from an
       * <code>InputStream</code> that contains the bytes of a
       * MimeMessage.
       *
       * @param key the prefix for the name of the temp file
       * @param in the stream containing the MimeMessage
       *
       * @throws MessagingException if an error occurs while trying to store
       *                            the stream
       */
      public MimeMessageInputStreamSource(String key, InputStream in)
              throws MessagingException {
          //We want to immediately read this into a temporary file
          //Create a temp file and channel the input stream into it
          OutputStream fout = null;
          try {
              file = File.createTempFile(key, ".m64");
              fout = new BufferedOutputStream(new FileOutputStream(file));
              int b = -1;
              while ((b = in.read()) != -1) {
                  fout.write(b);
              }
              fout.flush();
  
              sourceId = file.getCanonicalPath();
          } catch (IOException ioe) {
              // We had an IOException preparing the temporary file, so
              // don't just leave it around to garbage collect later.
              // It isn't as if we are going to use it after we throw
              // the MessagingException.
              if (fout != null) try {
                  fout.close();
                  fout = null;
              } catch (IOException _) {
                  // Ignored - logging unavailable to log this error.
              }
  
              if (file != null) {
                  file.delete();
                  file = null;
              }
  
              throw new MessagingException("Unable to retrieve the data: " + ioe.getMessage(), ioe);
         } finally {
             try {
                 if (fout != null) {
                     fout.close();
                 }
             } catch (IOException ioe) {
                 // Ignored - logging unavailable to log this non-fatal error.
             }
 
             try {
                 if (in != null) {
                     in.close();
                 }
             } catch (IOException ioe) {
                 // Ignored - logging unavailable to log this non-fatal error.
             }
         }
     }
 
     /***
      * Returns the unique identifier of this input stream source
      *
      * @return the unique identifier for this MimeMessageInputStreamSource
      */
     public String getSourceId() {
         return sourceId;
     }
 
     /***
      * Get an input stream to retrieve the data stored in the temporary file
      *
      * @return a <code>BufferedInputStream</code> containing the data
      */
     public synchronized InputStream getInputStream() throws IOException {
         return new SharedFileInputStream(file);
     }
 
     /***
      * Get the size of the temp file
      *
      * @return the size of the temp file
      *
      * @throws IOException if an error is encoutered while computing the size of the message
      */
     public long getMessageSize() throws IOException {
         return file.length();
     }
 
     /***
      * @see org.apache.avalon.framework.activity.Disposable#dispose()
      */
     public void dispose() {
         try {
             if (file != null && file.exists()) {
                 file.delete();
             }
         } catch (Exception e) {
             //ignore
         }
         file = null;
     }
 
     /***
      * <p>Finalizer that closes and deletes the temp file.  Very bad.</p>
      * We're leaving this in temporarily, while also establishing a more
      * formal mechanism for cleanup through use of the dispose() method.
      * @throws Throwable 
      *
     public void finalize() throws Throwable {
         dispose();
         super.finalize();
     }
      */
 }