/*
    * ====================================================================
    * 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.http.client.entity;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  /**
   * Lazy init InputStream wrapper.
   */
  class LazyDecompressingInputStream extends InputStream {
  
      private final InputStream wrappedStream;
      private final InputStreamFactory inputStreamFactory;
  
      private InputStream wrapperStream;
  
      public LazyDecompressingInputStream(
              final InputStream wrappedStream,
              final InputStreamFactory inputStreamFactory) {
          this.wrappedStream = wrappedStream;
          this.inputStreamFactory = inputStreamFactory;
      }
  
      private void initWrapper() throws IOException {
          if (wrapperStream == null) {
              wrapperStream = inputStreamFactory.create(wrappedStream);
          }
      }
  
      @Override
      public int read() throws IOException {
          initWrapper();
          return wrapperStream.read();
      }
  
      @Override
      public int read(final byte[] b) throws IOException {
          initWrapper();
          return wrapperStream.read(b);
      }
  
      @Override
      public int read(final byte[] b, final int off, final int len) throws IOException {
          initWrapper();
          return wrapperStream.read(b, off, len);
      }
  
      @Override
      public long skip(final long n) throws IOException {
          initWrapper();
          return wrapperStream.skip(n);
      }
  
      @Override
      public boolean markSupported() {
          return false;
      }
  
      @Override
      public int available() throws IOException {
          initWrapper();
          return wrapperStream.available();
      }
  
      @Override
      public void close() throws IOException {
          try {
              if (wrapperStream != null) {
                  wrapperStream.close();
              }
          } finally {
              wrappedStream.close();
          }
      }
 
 }