package org.apache.maven.repository.internal;
   
   /*
    * 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.Collection;
  import java.util.Collections;
  import java.util.Date;
  import java.util.LinkedHashMap;
  import java.util.Map;
  
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.deployment.DeployRequest;
  import org.eclipse.aether.impl.MetadataGenerator;
  import org.eclipse.aether.metadata.Metadata;
  import org.eclipse.aether.util.ConfigUtils;
  
  /**
   * @author Benjamin Bentmann
   */
  class RemoteSnapshotMetadataGenerator
      implements MetadataGenerator
  {
  
      private final Map<Object, RemoteSnapshotMetadata> snapshots;
  
      private final boolean legacyFormat;
  
      private final Date timestamp;
  
      RemoteSnapshotMetadataGenerator( RepositorySystemSession session, DeployRequest request )
      {
          legacyFormat = ConfigUtils.getBoolean( session, false, "maven.metadata.legacy" );
  
          timestamp = (Date) ConfigUtils.getObject( session, new Date(), "maven.startTime" );
  
          snapshots = new LinkedHashMap<>();
  
          /*
           * NOTE: This should be considered a quirk to support interop with Maven's legacy ArtifactDeployer which
           * processes one artifact at a time and hence cannot associate the artifacts from the same project to use the
           * same timestamp+buildno for the snapshot versions. Allowing the caller to pass in metadata from a previous
           * deployment allows to re-establish the association between the artifacts of the same project.
           */
          for ( Metadata metadata : request.getMetadata() )
          {
              if ( metadata instanceof RemoteSnapshotMetadata )
              {
                  RemoteSnapshotMetadata snapshotMetadata = (RemoteSnapshotMetadata) metadata;
                  snapshots.put( snapshotMetadata.getKey(), snapshotMetadata );
              }
          }
      }
  
      public Collection<? extends Metadata> prepare( Collection<? extends Artifact> artifacts )
      {
          for ( Artifact artifact : artifacts )
          {
              if ( artifact.isSnapshot() )
              {
                  Object key = RemoteSnapshotMetadata.getKey( artifact );
                  RemoteSnapshotMetadata snapshotMetadata = snapshots.get( key );
                  if ( snapshotMetadata == null )
                  {
                      snapshotMetadata = new RemoteSnapshotMetadata( artifact, legacyFormat, timestamp );
                      snapshots.put( key, snapshotMetadata );
                  }
                  snapshotMetadata.bind( artifact );
              }
          }
  
          return snapshots.values();
      }
  
      public Artifact transformArtifact( Artifact artifact )
      {
          if ( artifact.isSnapshot() && artifact.getVersion().equals( artifact.getBaseVersion() ) )
          {
              Object key = RemoteSnapshotMetadata.getKey( artifact );
              RemoteSnapshotMetadata snapshotMetadata = snapshots.get( key );
              if ( snapshotMetadata != null )
              {
                 artifact = artifact.setVersion( snapshotMetadata.getExpandedVersion( artifact ) );
             }
         }
 
         return artifact;
     }
 
     public Collection<? extends Metadata> finish( Collection<? extends Artifact> artifacts )
     {
         return Collections.emptyList();
     }
 
 }