/*
 * Copyright (c) 2003, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.bundle.http;

import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.OutputStream;


public class BodyOutputStream extends BufferedOutputStream {

  // private fields

  private int totalCount = 0;
  private int maxCount = Integer.MAX_VALUE;
  private boolean committed = false;
  private ResponseImpl response = null;


  // constructors

  BodyOutputStream(OutputStream out, ResponseImpl response, int size) {

    super(out);

    this.response = response;

    setBufferSize(size);
  }


  // package methods

  void setContentLength(int contentLength) {

    if (!committed)
      maxCount = contentLength;
  }

  int getBufferByteCount() {
    return count;
  }

  public synchronized void setBufferSize(int size) {

    if (totalCount != 0)
      throw new IllegalStateException("Buffer size cannot be changed when data has been written");

    if (size < 0)
      throw new IllegalArgumentException("Buffer size must not be negative: " + size);

    if (size > buf.length)
      buf = new byte[size];
  }

  public int getBufferSize() {
    return buf.length;
  }

  public synchronized void reset() {

    totalCount = 0;
    count = 0;
  }

  public synchronized boolean isCommitted() {
    return committed;
  }

  synchronized void flush(boolean commit) throws IOException {

    if (commit)
      flushBuffer();

    out.flush();
  }


  // protected methods

  protected void flushBuffer() throws IOException {

    if (!committed && response != null) {
      out.write(response.getHeaders());
      committed = true;
    }

    out.write(buf, 0, count);
    count = 0;
  }


  // extends BufferedOutputStream

  public synchronized void write(int b) throws IOException {

    if (count >= buf.length)
      flushBuffer();

    if (totalCount++ < maxCount)
      buf[count++] = (byte) b;
    else
      flushBuffer();
  }

  public synchronized void write(byte b[], int off, int len) throws IOException {

    if (len >= buf.length) {
      flushBuffer();
      out.write(b, off, len);
    } else {
      if (len > buf.length - count)
        flushBuffer();
      System.arraycopy(b, off, buf, count, len);
      totalCount += len;
      count += len;
    }
  }

  public void flush() { }

  public void close() { }

} // BodyOutputStream