package org.apache.maven.plugin.surefire.booterclient;
   
   /*
    * 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 org.apache.maven.artifact.Artifact;
  import org.apache.maven.artifact.repository.ArtifactRepository;
  
  import java.io.File;
  import java.security.MessageDigest;
  import java.security.NoSuchAlgorithmException;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import static java.nio.charset.StandardCharsets.UTF_8;
  
  /**
   * @author Kristian Rosenvold
   */
  public class ChecksumCalculator
  {
      private static final String HEX = "0123456789ABCDEF";
  
      private final List<Object> checksumItems = new ArrayList<>();
  
      private void appendObject( Object item )
      {
          checksumItems.add( item );
      }
  
      public void add( boolean value )
      {
          checksumItems.add( value );
      }
  
      public void add( int value )
      {
          checksumItems.add( value );
      }
  
      public void add( double value )
      {
          checksumItems.add( value );
      }
  
      public void add( Map<?, ?> map )
      {
          if ( map != null )
          {
              appendObject( map.toString() );
          }
      }
  
      public void add( String string )
      {
          appendObject( string );
      }
  
      public void add( File workingDirectory )
      {
          appendObject( workingDirectory );
      }
  
      public void add( ArtifactRepository localRepository )
      {
          appendObject( localRepository );
      }
  
      public void add( List<?> items )
      {
          if ( items != null )
          {
              for ( Object item : items )
              {
                  appendObject( item );
              }
          }
          else
          {
              appendObject( null );
          }
  
     }
 
     public void add( Object[] items )
     {
         if ( items != null )
         {
             for ( Object item : items )
             {
                 appendObject( item );
             }
         }
         else
         {
             appendObject( null );
         }
     }
 
     public void add( Artifact artifact )
     {
         appendObject( artifact != null ? artifact.getId() : null );
     }
 
     public void add( Boolean aBoolean )
     {
         appendObject( aBoolean );
     }
 
     @SuppressWarnings( "checkstyle:magicnumber" )
     private static String asHexString( byte[] bytes )
     {
         if ( bytes == null )
         {
             return null;
         }
         final StringBuilder result = new StringBuilder( 2 * bytes.length );
         for ( byte b : bytes )
         {
             result.append( HEX.charAt( ( b & 0xF0 ) >> 4 ) ).append( HEX.charAt( ( b & 0x0F ) ) );
         }
         return result.toString();
     }
 
     private String getConfig()
     {
         StringBuilder result = new StringBuilder();
         for ( Object checksumItem : checksumItems )
         {
             result.append( checksumItem != null ? checksumItem.toString() : "null" );
         }
         return result.toString();
     }
 
     public String getSha1()
     {
         try
         {
             MessageDigest md = MessageDigest.getInstance( "SHA-1" );
             String configValue = getConfig();
             byte[] configBytes = configValue.getBytes( UTF_8 );
             md.update( configBytes );
             byte[] sha1hash = md.digest();
             return asHexString( sha1hash );
         }
         catch ( NoSuchAlgorithmException e )
         {
             throw new RuntimeException( e );
         }
     }
 
 }