package org.apache.maven.plugin.surefire.report;
   
   /*
    * 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.
   */
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.RandomAccessFile;
  import java.io.UncheckedIOException;
  import java.lang.ref.SoftReference;
  import java.nio.Buffer;
  import java.nio.ByteBuffer;
  import java.nio.file.Path;
  
  import static java.nio.charset.StandardCharsets.UTF_8;
  import static java.nio.file.Files.notExists;
  import static java.nio.file.Files.size;
  import static java.util.Objects.requireNonNull;
  import static org.apache.maven.surefire.api.util.internal.StringUtils.NL;
  
  import org.apache.maven.surefire.api.util.SureFireFileManager;
  
  /**
   * A deferred file output stream decorator that encodes the string from the VM to UTF-8.
   * <br>
   * The deferred file is temporary file, and it is created at the first {@link #write(String, boolean) write}.
   * The {@link #writeTo(OutputStream) reads} can be called anytime.
   * It is highly recommended to {@link #commit() commit} the cache which would close the file stream
   * and subsequent reads may continue.
   * The {@link #free()} method would commit and delete the deferred file.
   *
   * @author Andreas Gudian
   */
  final class Utf8RecodingDeferredFileOutputStream
  {
      private static final byte[] NL_BYTES = NL.getBytes( UTF_8 );
      public static final int CACHE_SIZE = 64 * 1024;
  
      private final String channel;
      private Path file;
      private RandomAccessFile storage;
      private boolean closed;
      private SoftReference<byte[]> largeCache;
      private ByteBuffer cache;
      private boolean isDirty;
  
      Utf8RecodingDeferredFileOutputStream( String channel )
      {
          this.channel = requireNonNull( channel );
      }
  
      public synchronized void write( String output, boolean newLine )
          throws IOException
      {
          if ( closed )
          {
              return;
          }
  
          if ( storage == null )
          {
  
              file = SureFireFileManager.createTempFile( channel, "deferred" ).toPath();
              storage = new RandomAccessFile( file.toFile(), "rw" );
          }
  
          if ( output == null )
          {
              output = "null";
          }
  
          if ( cache == null )
          {
              cache = ByteBuffer.allocate( CACHE_SIZE );
          }
  
          isDirty = true;
  
          byte[] decodedString = output.getBytes( UTF_8 );
          int newLineLength = newLine ? NL_BYTES.length : 0;
          if ( cache.remaining() >= decodedString.length + newLineLength )
          {
              cache.put( decodedString );
             if ( newLine )
             {
                 cache.put( NL_BYTES );
             }
         }
         else
         {
             ( (Buffer) cache ).flip();
             int minLength = cache.remaining() + decodedString.length + NL_BYTES.length;
             byte[] buffer = getLargeCache( minLength );
             int bufferLength = 0;
             System.arraycopy( cache.array(), cache.arrayOffset() + ( (Buffer) cache ).position(),
                 buffer, bufferLength, cache.remaining() );
             bufferLength += cache.remaining();
             ( (Buffer) cache ).clear();
 
             System.arraycopy( decodedString, 0, buffer, bufferLength, decodedString.length );
             bufferLength += decodedString.length;
 
             if ( newLine )
             {
                 System.arraycopy( NL_BYTES, 0, buffer, bufferLength, NL_BYTES.length );
                 bufferLength += NL_BYTES.length;
             }
 
             storage.write( buffer, 0, bufferLength );
         }
     }
 
     public synchronized long getByteCount()
     {
         try
         {
             sync();
             if ( storage != null && !closed )
             {
                 storage.getFD().sync();
             }
             return file == null ? 0 : size( file );
         }
         catch ( IOException e )
         {
             return 0;
         }
     }
 
     @SuppressWarnings( "checkstyle:innerassignment" )
     public synchronized void writeTo( OutputStream out )
         throws IOException
     {
         if ( file != null && notExists( file ) )
         {
             storage = null;
         }
 
         if ( ( storage == null && file != null ) || ( storage != null && !storage.getChannel().isOpen() ) )
         {
             storage = new RandomAccessFile( file.toFile(), "rw" );
         }
 
         if ( storage != null )
         {
             sync();
             final long currentFilePosition = storage.getFilePointer();
             storage.seek( 0L );
             try
             {
                 byte[] buffer = new byte[CACHE_SIZE];
                 for ( int readCount; ( readCount = storage.read( buffer ) ) != -1; )
                 {
                     out.write( buffer, 0, readCount );
                 }
             }
             finally
             {
                 storage.seek( currentFilePosition );
             }
         }
     }
 
     public synchronized void commit()
     {
         if ( storage == null )
         {
             return;
         }
 
         try
         {
             sync();
             storage.close();
         }
         catch ( IOException e )
         {
             throw new UncheckedIOException( e );
         }
         finally
         {
             storage = null;
             cache = null;
             largeCache = null;
         }
     }
 
     public synchronized void free()
     {
         if ( !closed )
         {
             closed = true;
             if ( file != null )
             {
                 try
                 {
                     commit();
                     //todo delete( file ); uncomment L485 assertThat( file ).doesNotExist() in StatelessXmlReporterTest
                 }
                 catch ( /*todo uncomment IOException |*/ UncheckedIOException e )
                 {
                     /*todo uncomment file.toFile()
                         .deleteOnExit();*/
                 }
                 finally
                 {
                     // todo should be removed after uncommented delete( file )
                     file.toFile()
                         .deleteOnExit();
                 }
 
                 storage = null;
                 cache = null;
                 largeCache = null;
             }
         }
     }
 
     private void sync() throws IOException
     {
         if ( !isDirty )
         {
             return;
         }
 
         isDirty = false;
 
         if ( storage != null && cache != null )
         {
             ( (Buffer) cache ).flip();
             byte[] array = cache.array();
             int offset = cache.arrayOffset() + ( (Buffer) cache ).position();
             int length = cache.remaining();
             ( (Buffer) cache ).clear();
             storage.write( array, offset, length );
             // the data that you wrote with the mode "rw" may still only be kept in memory and may be read back
             // storage.getFD().sync();
         }
     }
 
     @SuppressWarnings( "checkstyle:innerassignment" )
     private byte[] getLargeCache( int minLength )
     {
         byte[] buffer;
         if ( largeCache == null || ( buffer = largeCache.get() ) == null || buffer.length < minLength )
         {
             buffer = new byte[minLength];
             largeCache = new SoftReference<>( buffer );
         }
         return buffer;
     }
 }