package org.eclipse.aether.util.repository;
   
   /*
    * 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.util.Arrays;
  import java.util.Collection;
  import java.util.Map;
  
  import org.eclipse.aether.repository.Authentication;
  import org.eclipse.aether.repository.AuthenticationContext;
  import org.eclipse.aether.repository.AuthenticationDigest;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Authentication that aggregates other authentication blocks. When multiple input authentication blocks provide the
   * same authentication key, the last written value wins.
   */
  final class ChainedAuthentication
      implements Authentication
  {
  
      private final Authentication[] authentications;
  
      ChainedAuthentication( Authentication... authentications )
      {
          if ( authentications != null && authentications.length > 0 )
          {
              this.authentications = authentications.clone();
          }
          else
          {
              this.authentications = new Authentication[0];
          }
      }
  
      ChainedAuthentication( Collection<? extends Authentication> authentications )
      {
          if ( authentications != null && !authentications.isEmpty() )
          {
              this.authentications = authentications.toArray( new Authentication[authentications.size()] );
          }
          else
          {
              this.authentications = new Authentication[0];
          }
      }
  
      public void fill( AuthenticationContext context, String key, Map<String, String> data )
      {
          requireNonNull( context, "context cannot be null" );
          for ( Authentication authentication : authentications )
          {
              authentication.fill( context, key, data );
          }
      }
  
      public void digest( AuthenticationDigest digest )
      {
          requireNonNull( digest, "digest cannot be null" );
          for ( Authentication authentication : authentications )
          {
              authentication.digest( digest );
          }
      }
  
      @Override
      public boolean equals( Object obj )
      {
          if ( this == obj )
          {
              return true;
          }
          if ( obj == null || !getClass().equals( obj.getClass() ) )
          {
              return false;
          }
          ChainedAuthentication that = (ChainedAuthentication) obj;
          return Arrays.equals( authentications, that.authentications );
      }
  
      @Override
     public int hashCode()
     {
         return Arrays.hashCode( authentications );
     }
 
     @Override
     public String toString()
     {
         StringBuilder buffer = new StringBuilder( 256 );
         for ( Authentication authentication : authentications )
         {
             if ( buffer.length() > 0 )
             {
                 buffer.append( ", " );
             }
             buffer.append( authentication );
         }
         return buffer.toString();
     }
 
 }