package org.eclipse.aether.internal.impl;
   
   /*
    * 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 javax.inject.Named;
  import javax.inject.Singleton;
  
  import java.io.BufferedInputStream;
  import java.io.BufferedOutputStream;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.UncheckedIOException;
  import java.nio.ByteBuffer;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.nio.file.StandardCopyOption;
  
  import org.eclipse.aether.spi.io.FileProcessor;
  import org.eclipse.aether.util.ChecksumUtils;
  import org.eclipse.aether.util.FileUtils;
  
  /**
   * A utility class helping with file-based operations.
   */
  @Singleton
  @Named
  public class DefaultFileProcessor
          implements FileProcessor
  {
  
      /**
       * Thread-safe variant of {@link File#mkdirs()}. Creates the directory named by the given abstract pathname,
       * including any necessary but nonexistent parent directories. Note that if this operation fails it may have
       * succeeded in creating some of the necessary parent directories.
       *
       * @param directory The directory to create, may be {@code null}.
       * @return {@code true} if and only if the directory was created, along with all necessary parent directories;
       * {@code false} otherwise
       */
      public boolean mkdirs( File directory )
      {
          if ( directory == null )
          {
              return false;
          }
  
          if ( directory.exists() )
          {
              return false;
          }
          if ( directory.mkdir() )
          {
              return true;
          }
  
          File canonDir;
          try
          {
              canonDir = directory.getCanonicalFile();
          }
          catch ( IOException e )
          {
              throw new UncheckedIOException( e );
          }
  
          File parentDir = canonDir.getParentFile();
          return ( parentDir != null && ( mkdirs( parentDir ) || parentDir.exists() ) && canonDir.mkdir() );
      }
  
      public void write( File target, String data )
              throws IOException
      {
          FileUtils.writeFile( target.toPath(), p -> Files.write( p, data.getBytes( StandardCharsets.UTF_8 ) ) );
      }
  
      public void write( File target, InputStream source )
              throws IOException
      {
          FileUtils.writeFile( target.toPath(), p -> Files.copy( source, p, StandardCopyOption.REPLACE_EXISTING ) );
      }
 
     public void copy( File source, File target )
             throws IOException
     {
         copy( source, target, null );
     }
 
     public long copy( File source, File target, ProgressListener listener )
             throws IOException
     {
         try ( InputStream in = new BufferedInputStream( Files.newInputStream( source.toPath() ) );
               FileUtils.CollocatedTempFile tempTarget = FileUtils.newTempFile( target.toPath() );
               OutputStream out = new BufferedOutputStream( Files.newOutputStream( tempTarget.getPath() ) ) )
         {
             long result = copy( out, in, listener );
             tempTarget.move();
             return result;
         }
     }
 
     private long copy( OutputStream os, InputStream is, ProgressListener listener )
             throws IOException
     {
         long total = 0L;
         byte[] buffer = new byte[1024 * 32];
         while ( true )
         {
             int bytes = is.read( buffer );
             if ( bytes < 0 )
             {
                 break;
             }
 
             os.write( buffer, 0, bytes );
 
             total += bytes;
 
             if ( listener != null && bytes > 0 )
             {
                 try
                 {
                     listener.progressed( ByteBuffer.wrap( buffer, 0, bytes ) );
                 }
                 catch ( Exception e )
                 {
                     // too bad
                 }
             }
         }
 
         return total;
     }
 
     public void move( File source, File target )
             throws IOException
     {
         if ( !source.renameTo( target ) )
         {
             copy( source, target );
 
             target.setLastModified( source.lastModified() );
 
             source.delete();
         }
     }
 
     @Override
     public String readChecksum( final File checksumFile ) throws IOException
     {
         // for now do exactly same as happened before, but FileProcessor is a component and can be replaced
         return ChecksumUtils.read( checksumFile );
     }
 
     @Override
     public void writeChecksum( final File checksumFile, final String checksum ) throws IOException
     {
         // for now do exactly same as happened before, but FileProcessor is a component and can be replaced
         write( checksumFile, checksum );
     }
 }