/*
    * 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
    *
   *   https://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.commons.compress.compressors.deflate64;
  
  import java.io.Closeable;
  import java.io.IOException;
  import java.io.InputStream;
  
  import org.apache.commons.compress.compressors.CompressorInputStream;
  import org.apache.commons.compress.utils.InputStreamStatistics;
  import org.apache.commons.io.IOUtils;
  
  /**
   * Deflate64 decompressor.
   *
   * @since 1.16
   * @NotThreadSafe
   */
  public class Deflate64CompressorInputStream extends CompressorInputStream implements InputStreamStatistics {
      private InputStream originalStream;
      private HuffmanDecoder decoder;
      private long compressedBytesRead;
      private final byte[] oneByte = new byte[1];
  
      Deflate64CompressorInputStream(final HuffmanDecoder decoder) {
          this.decoder = decoder;
      }
  
      /**
       * Constructs a Deflate64CompressorInputStream.
       *
       * @param in the stream to read from
       */
      public Deflate64CompressorInputStream(final InputStream in) {
          this(new HuffmanDecoder(in));
          originalStream = in;
      }
  
      @Override
      public int available() throws IOException {
          return decoder != null ? decoder.available() : 0;
      }
  
      @Override
      public void close() throws IOException {
          try {
              closeDecoder();
          } finally {
              IOUtils.close(originalStream);
              originalStream = null;
          }
      }
  
      private void closeDecoder() {
          final Closeable c = decoder;
          IOUtils.closeQuietly(c);
          decoder = null;
      }
  
      /**
       * @since 1.17
       */
      @Override
      public long getCompressedCount() {
          return compressedBytesRead;
      }
  
      /**
       * @throws java.io.EOFException if the underlying stream is exhausted before the end of deflated data was reached.
       */
      @Override
      public int read() throws IOException {
          while (true) {
              final int r = read(oneByte);
              switch (r) {
              case 1:
                  return oneByte[0] & 0xFF;
              case -1:
                  return -1;
              case 0:
                  continue;
              default:
                  throw new IllegalStateException("Invalid return value from read: " + r);
             }
         }
     }
 
     /**
      * @throws java.io.EOFException if the underlying stream is exhausted before the end of deflated data was reached.
      */
     @Override
     public int read(final byte[] b, final int off, final int len) throws IOException {
         if (len == 0) {
             return 0;
         }
         int read = -1;
         if (decoder != null) {
             try {
                 read = decoder.decode(b, off, len);
             } catch (final RuntimeException ex) {
                 throw new IOException("Invalid Deflate64 input", ex);
             }
             compressedBytesRead = decoder.getBytesRead();
             count(read);
             if (read == -1) {
                 closeDecoder();
             }
         }
         return read;
     }
 }