/*
    *  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.
   */
  package org.apache.commons.compress.archivers.zip;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.channels.FileChannel;
  import java.nio.file.OpenOption;
  import java.nio.file.Path;
  import java.nio.file.StandardOpenOption;
  import java.util.Objects;
  
  /**
   * {@link RandomAccessOutputStream} implementation based on a file.
   */
  // Keep package-private; consider for Apache Commons IO.
  class FileRandomAccessOutputStream extends RandomAccessOutputStream {
  
      private final FileChannel channel;
  
      private long position;
  
      FileRandomAccessOutputStream(final FileChannel channel) {
          this.channel = Objects.requireNonNull(channel, "channel");
      }
  
      FileRandomAccessOutputStream(final Path file) throws IOException {
          this(file, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.WRITE);
      }
  
      FileRandomAccessOutputStream(final Path file, final OpenOption... options) throws IOException {
          this(FileChannel.open(file, options));
      }
  
      FileChannel channel() {
          return channel;
      }
  
      @Override
      public void close() throws IOException {
          channel.close();
      }
  
      @Override
      public synchronized long position() {
          return position;
      }
  
      @Override
      public synchronized void write(final byte[] b, final int off, final int len) throws IOException {
          ZipIoUtil.writeFully(this.channel, ByteBuffer.wrap(b, off, len));
          position += len;
      }
  
      @Override
      public void writeFully(final byte[] b, final int off, final int len, final long atPosition) throws IOException {
          final ByteBuffer buf = ByteBuffer.wrap(b, off, len);
          for (long currentPos = atPosition; buf.hasRemaining();) {
              final int written = this.channel.write(buf, currentPos);
              if (written <= 0) {
                  throw new IOException("Failed to fully write to file: written=" + written);
              }
              currentPos += written;
          }
      }
  }