/*
    *  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.parallel;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.UncheckedIOException;
  import java.nio.file.Files;
  import java.nio.file.Path;
  
  /**
   * ScatterGatherBackingStore that is backed by a path.
   *
   * @since 1.10
   */
  public class FileBasedScatterGatherBackingStore implements ScatterGatherBackingStore {
      private final Path target;
      private final OutputStream outputStream;
      private boolean closed;
  
      public FileBasedScatterGatherBackingStore(final File target) throws FileNotFoundException {
          this(target.toPath());
      }
  
      /**
       * Constructs a new instance for the given path.
       *
       * @param target The path to offload compressed data into.
       * @throws FileNotFoundException if the file doesn't exist
       * @since 1.22
       */
      public FileBasedScatterGatherBackingStore(final Path target) throws FileNotFoundException {
          this.target = target;
          try {
              outputStream = Files.newOutputStream(target);
          } catch (final FileNotFoundException ex) {
              throw ex;
          } catch (final IOException ex) {
              // must convert exception to stay backwards compatible with Compress 1.10 to 1.13
              throw new UncheckedIOException(ex); // NOSONAR
          }
      }
  
      @Override
      public void close() throws IOException {
          try {
              closeForWriting();
          } finally {
              Files.deleteIfExists(target);
          }
      }
  
      @Override
      public void closeForWriting() throws IOException {
          if (!closed) {
              outputStream.close();
              closed = true;
          }
      }
  
      @Override
      public InputStream getInputStream() throws IOException {
          return Files.newInputStream(target);
      }
  
      @Override
      public void writeOut(final byte[] data, final int offset, final int length) throws IOException {
          outputStream.write(data, offset, length);
      }
  }