/*
    * 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.apache.maven.plugins.pmd;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  import javax.inject.Provider;
  import javax.inject.Singleton;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  import java.util.Optional;
  import java.util.stream.Collectors;
  import java.util.stream.Stream;
  
  import org.apache.maven.RepositoryUtils;
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.model.Dependency;
  import org.apache.maven.model.DependencyManagement;
  import org.apache.maven.project.MavenProject;
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.artifact.ArtifactTypeRegistry;
  import org.eclipse.aether.collection.CollectRequest;
  import org.eclipse.aether.resolution.ArtifactResult;
  import org.eclipse.aether.resolution.DependencyRequest;
  import org.eclipse.aether.resolution.DependencyResolutionException;
  import org.eclipse.aether.resolution.DependencyResult;
  
  /**
   * utils service for provide configuration needed to execute CPD/PMD.
   */
  @Named
  @Singleton
  public class ConfigurationService {
  
      private final Provider<MavenSession> sessionProvider;
  
      private final org.eclipse.aether.RepositorySystem repositorySystem;
  
      @Inject
      public ConfigurationService(
              Provider<MavenSession> sessionProvider, org.eclipse.aether.RepositorySystem repositorySystem) {
          this.sessionProvider = sessionProvider;
          this.repositorySystem = repositorySystem;
      }
  
      public List<File> resolveDependenciesAsFile(
              MavenProject localProject, Collection<MavenProject> aggregatedProjects, boolean includeTests)
              throws DependencyResolutionException {
  
          RepositorySystemSession repositorySession = sessionProvider.get().getRepositorySession();
          ArtifactTypeRegistry artifactTypeRegistry = repositorySession.getArtifactTypeRegistry();
  
          List<String> includesScope =
                  includeTests ? Arrays.asList("compile", "provided", "test") : Arrays.asList("compile", "provided");
  
          // collect exclusions for projects within the reactor
          // if module a depends on module b and both are in the reactor
          // then we don't want to resolve the dependency as an artifact.
          List<String> exclusionPatterns = new ArrayList<>();
          for (MavenProject project : aggregatedProjects) {
              exclusionPatterns.add(getExclusionKey(project));
          }
  
          List<org.eclipse.aether.graph.Dependency> dependencies = localProject.getDependencies().stream()
                  .filter(dependency -> includesScope.contains(dependency.getScope()))
                  .filter(dependency -> !exclusionPatterns.contains(getExclusionKey(dependency)))
                  .map(d -> RepositoryUtils.toDependency(d, artifactTypeRegistry))
                  .collect(Collectors.toList());
  
          List<org.eclipse.aether.graph.Dependency> dependencyManagements = Optional.ofNullable(
                          localProject.getDependencyManagement())
                  .map(DependencyManagement::getDependencies)
                  .map(Collection::stream)
                  .orElse(Stream.empty())
                  .map(d -> RepositoryUtils.toDependency(d, artifactTypeRegistry))
                  .collect(Collectors.toList());
  
          CollectRequest collectRequest =
                 new CollectRequest(dependencies, dependencyManagements, localProject.getRemoteProjectRepositories());
         DependencyRequest request = new DependencyRequest(collectRequest, null);
 
         DependencyResult result =
                 repositorySystem.resolveDependencies(sessionProvider.get().getRepositorySession(), request);
 
         return result.getArtifactResults().stream()
                 .map(ArtifactResult::getArtifact)
                 .map(Artifact::getFile)
                 .collect(Collectors.toList());
     }
 
     private String getExclusionKey(Dependency dependency) {
         return dependency.getGroupId() + ":" + dependency.getArtifactId();
     }
 
     private String getExclusionKey(MavenProject project) {
         return project.getGroupId() + ":" + project.getArtifactId();
     }
 }