/*
    * 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.
   */
  package org.eclipse.aether.internal.impl.synccontext;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.SyncContext;
  import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapter;
  import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapterFactory;
  import org.eclipse.aether.spi.synccontext.SyncContextFactory;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Default {@link SyncContextFactory} implementation that uses named locks.
   * <p>
   * The implementation relies fully on {@link NamedLockFactoryAdapterFactory} and all it does is just "stuff" the
   * adapter instance into session, hence factory is called only when given session has no instance created.
   */
  @Singleton
  @Named
  public final class DefaultSyncContextFactory implements SyncContextFactory {
      private static final String ADAPTER_KEY = DefaultSyncContextFactory.class.getName() + ".adapter";
  
      private final NamedLockFactoryAdapterFactory namedLockFactoryAdapterFactory;
  
      /**
       * Constructor used with DI, where factories are injected and selected based on key.
       */
      @Inject
      public DefaultSyncContextFactory(final NamedLockFactoryAdapterFactory namedLockFactoryAdapterFactory) {
          this.namedLockFactoryAdapterFactory = requireNonNull(namedLockFactoryAdapterFactory);
      }
  
      @Override
      public SyncContext newInstance(final RepositorySystemSession session, final boolean shared) {
          requireNonNull(session, "session cannot be null");
          NamedLockFactoryAdapter adapter = (NamedLockFactoryAdapter) session.getData()
                  .computeIfAbsent(ADAPTER_KEY, () -> namedLockFactoryAdapterFactory.getAdapter(session));
          return adapter.newInstance(session, shared);
      }
  }