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 java.util.regex.Pattern;
  
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.impl.OfflineController;
  import org.eclipse.aether.repository.RemoteRepository;
  import org.eclipse.aether.transfer.RepositoryOfflineException;
  import org.eclipse.aether.util.ConfigUtils;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * 
   */
  @Singleton
  @Named
  public class DefaultOfflineController
      implements OfflineController
  {
  
      static final String CONFIG_PROP_OFFLINE_PROTOCOLS = "aether.offline.protocols";
  
      static final String CONFIG_PROP_OFFLINE_HOSTS = "aether.offline.hosts";
  
      private static final Pattern SEP = Pattern.compile( "\\s*,\\s*" );
  
      public DefaultOfflineController()
      {
          // enables default constructor
      }
  
      public void checkOffline( RepositorySystemSession session, RemoteRepository repository )
          throws RepositoryOfflineException
      {
          requireNonNull( session, "session cannot be null" );
          requireNonNull( repository, "repository cannot be null" );
          if ( isOfflineProtocol( session, repository ) || isOfflineHost( session, repository ) )
          {
              return;
          }
  
          throw new RepositoryOfflineException( repository );
      }
  
      private boolean isOfflineProtocol( RepositorySystemSession session, RemoteRepository repository )
      {
          String[] protocols = getConfig( session, CONFIG_PROP_OFFLINE_PROTOCOLS );
          if ( protocols != null )
          {
              String protocol = repository.getProtocol();
              if ( protocol.length() > 0 )
              {
                  for ( String p : protocols )
                  {
                      if ( p.equalsIgnoreCase( protocol ) )
                      {
                          return true;
                      }
                  }
              }
          }
          return false;
      }
  
      private boolean isOfflineHost( RepositorySystemSession session, RemoteRepository repository )
      {
          String[] hosts = getConfig( session, CONFIG_PROP_OFFLINE_HOSTS );
          if ( hosts != null )
          {
              String host = repository.getHost();
              if ( host.length() > 0 )
              {
                  for ( String h : hosts )
                  {
                      if ( h.equalsIgnoreCase( host ) )
                      {
                         return true;
                     }
                 }
             }
         }
         return false;
     }
 
     private String[] getConfig( RepositorySystemSession session, String key )
     {
         String value = ConfigUtils.getString( session, "", key ).trim();
         if ( value.isEmpty() )
         {
             return null;
         }
         return SEP.split( value );
     }
 
 }