/*
    * 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.scope;
  
  import org.eclipse.aether.collection.DependencyGraphTransformationContext;
  import org.eclipse.aether.collection.DependencyGraphTransformer;
  import org.eclipse.aether.graph.Dependency;
  import org.eclipse.aether.graph.DependencyNode;
  import org.eclipse.aether.impl.scope.BuildScope;
  import org.eclipse.aether.impl.scope.InternalScopeManager;
  import org.eclipse.aether.scope.DependencyScope;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * A dependency graph transformer that refines the request context for nodes that belong to the "project" context by
   * appending the buildpath type to which the node belongs. For instance, a compile-time project dependency will be
   * assigned the request context "project/compile".
   * <p>
   * This class also "bridges" between {@link DependencyScope} and Resolver that uses plain string labels for scopes.
   *
   * @see DependencyNode#getRequestContext()
   */
  public final class ManagedDependencyContextRefiner implements DependencyGraphTransformer {
      private final InternalScopeManager scopeManager;
  
      public ManagedDependencyContextRefiner(InternalScopeManager scopeManager) {
          this.scopeManager = requireNonNull(scopeManager, "scopeManager");
      }
  
      @Override
      public DependencyNode transformGraph(DependencyNode node, DependencyGraphTransformationContext context) {
          requireNonNull(node, "node cannot be null");
          requireNonNull(context, "context cannot be null");
          String ctx = node.getRequestContext();
  
          if ("project".equals(ctx)) {
              String scope = getBuildpathScope(node);
              if (scope != null) {
                  ctx += '/' + scope;
                  node.setRequestContext(ctx);
              }
          }
  
          for (DependencyNode child : node.getChildren()) {
              transformGraph(child, context);
          }
  
          return node;
      }
  
      private String getBuildpathScope(DependencyNode node) {
          Dependency dependency = node.getDependency();
          if (dependency == null) {
              return null;
          }
  
          return scopeManager
                  .getDependencyScope(dependency.getScope())
                  .flatMap(s ->
                          scopeManager.getDependencyScopeMainProjectBuildScope(s).map(BuildScope::getId))
                  .orElse(null);
      }
  }