package org.apache.maven.shared.dependency.analyzer;
   
   /*
    * 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.io.File;
  import java.io.IOException;
  import java.net.URL;
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.LinkedHashMap;
  import java.util.LinkedHashSet;
  import java.util.Map;
  import java.util.Set;
  import java.util.jar.JarEntry;
  import java.util.jar.JarFile;
  
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.project.MavenProject;
  import org.codehaus.plexus.component.annotations.Component;
  import org.codehaus.plexus.component.annotations.Requirement;
  
  /**
   * <p>DefaultProjectDependencyAnalyzer class.</p>
   *
   * @author <a href="mailto:markhobson@gmail.com">Mark Hobson</a>
   */
  @Component( role = ProjectDependencyAnalyzer.class )
  public class DefaultProjectDependencyAnalyzer
      implements ProjectDependencyAnalyzer
  {
      /**
       * ClassAnalyzer
       */
      @Requirement
      private ClassAnalyzer classAnalyzer;
  
      /**
       * DependencyAnalyzer
       */
      @Requirement
      private DependencyAnalyzer dependencyAnalyzer;
  
      /** {@inheritDoc} */
      public ProjectDependencyAnalysis analyze( MavenProject project )
          throws ProjectDependencyAnalyzerException
      {
          try
          {
              Map<Artifact, Set<String>> artifactClassMap = buildArtifactClassMap( project );
  
              Set<String> dependencyClasses = buildDependencyClasses( project );
              Set<String> mainDependencyClasses = buildMainDependencyClasses( project );
  
              Set<String> testOnlyDependencyClasses = buildTestDependencyClasses( project );
  
              Set<Artifact> declaredArtifacts = buildDeclaredArtifacts( project );
  
              Map<Artifact, Set<String>> usedArtifacts = buildUsedArtifacts( artifactClassMap, dependencyClasses );
              Set<Artifact>  mainUsedArtifacts = buildUsedArtifacts( artifactClassMap, mainDependencyClasses ).keySet();
  
              Set<Artifact>  testArtifacts = buildUsedArtifacts( artifactClassMap, testOnlyDependencyClasses ).keySet();
              Set<Artifact> testOnlyArtifacts = removeAll( testArtifacts, mainUsedArtifacts );
  
              Set<Artifact> usedDeclaredArtifacts = new LinkedHashSet<>( declaredArtifacts );
              usedDeclaredArtifacts.retainAll( usedArtifacts.keySet() );
  
              Map<Artifact, Set<String>> usedUndeclaredArtifactsWithClasses = new LinkedHashMap<>( usedArtifacts );
              Set<Artifact> usedUndeclaredArtifacts = removeAll(
                      usedUndeclaredArtifactsWithClasses.keySet(), declaredArtifacts );
              usedUndeclaredArtifactsWithClasses.keySet().retainAll( usedUndeclaredArtifacts );
  
              Set<Artifact> unusedDeclaredArtifacts = new LinkedHashSet<>( declaredArtifacts );
              unusedDeclaredArtifacts = removeAll( unusedDeclaredArtifacts, usedArtifacts.keySet() );
  
              Set<Artifact> testArtifactsWithNonTestScope = getTestArtifactsWithNonTestScope( testOnlyArtifacts );
  
              return new ProjectDependencyAnalysis( usedDeclaredArtifacts, usedUndeclaredArtifactsWithClasses,
                                                    unusedDeclaredArtifacts, testArtifactsWithNonTestScope );
          }
          catch ( IOException exception )
         {
             throw new ProjectDependencyAnalyzerException( "Cannot analyze dependencies", exception );
         }
     }
 
     /**
      * This method defines a new way to remove the artifacts by using the conflict id. We don't care about the version
      * here because there can be only 1 for a given artifact anyway.
      * 
      * @param start initial set
      * @param remove set to exclude
      * @return set with remove excluded
      */
     private Set<Artifact> removeAll( Set<Artifact> start, Set<Artifact> remove )
     {
         Set<Artifact> results = new LinkedHashSet<>( start.size() );
 
         for ( Artifact artifact : start )
         {
             boolean found = false;
 
             for ( Artifact artifact2 : remove )
             {
                 if ( artifact.getDependencyConflictId().equals( artifact2.getDependencyConflictId() ) )
                 {
                     found = true;
                     break;
                 }
             }
 
             if ( !found )
             {
                 results.add( artifact );
             }
         }
 
         return results;
     }
 
     private Set<Artifact> getTestArtifactsWithNonTestScope( Set<Artifact> testOnlyArtifacts )
     {
         Set<Artifact> nonTestScopeArtifacts = new LinkedHashSet<>();
 
         for ( Artifact artifact : testOnlyArtifacts )
         {
             if ( artifact.getScope().equals( "compile" ) )
             {
                 nonTestScopeArtifacts.add( artifact );
             }
         }
 
         return nonTestScopeArtifacts;
     }
 
     private Map<Artifact, Set<String>> buildArtifactClassMap( MavenProject project )
         throws IOException
     {
         Map<Artifact, Set<String>> artifactClassMap = new LinkedHashMap<>();
 
         Set<Artifact> dependencyArtifacts = project.getArtifacts();
 
         for ( Artifact artifact : dependencyArtifacts )
         {
             File file = artifact.getFile();
 
             if ( file != null && file.getName().endsWith( ".jar" ) )
             {
                 // optimized solution for the jar case
 
                 try ( JarFile jarFile = new JarFile( file ) )
                 {
                     Enumeration<JarEntry> jarEntries = jarFile.entries();
 
                     Set<String> classes = new HashSet<>();
 
                     while ( jarEntries.hasMoreElements() )
                     {
                         String entry = jarEntries.nextElement().getName();
                         if ( entry.endsWith( ".class" ) )
                         {
                             String className = entry.replace( '/', '.' );
                             className = className.substring( 0, className.length() - ".class".length() );
                             classes.add( className );
                         }
                     }
 
                     artifactClassMap.put( artifact, classes );
                 }
             }
             else if ( file != null && file.isDirectory() )
             {
                 URL url = file.toURI().toURL();
                 Set<String> classes = classAnalyzer.analyze( url );
 
                 artifactClassMap.put( artifact, classes );
             }
         }
 
         return artifactClassMap;
     }
 
     private Set<String> buildTestDependencyClasses( MavenProject project ) throws IOException
     {
         Set<String> testOnlyDependencyClasses = new HashSet<>();
 
         String outputDirectory = project.getBuild().getOutputDirectory();
         Set<String> nonTestDependencyClasses = new HashSet<>( buildDependencyClasses( outputDirectory ) );
 
         String testOutputDirectory = project.getBuild().getTestOutputDirectory();
         Set<String> testDependencyClasses = new HashSet<>( buildDependencyClasses( testOutputDirectory ) );
 
         for ( String testString : testDependencyClasses )
         {
             if ( !nonTestDependencyClasses.contains( testString ) )
             {
                 testOnlyDependencyClasses.add( testString );
             }
         }
 
         return testOnlyDependencyClasses;
     }
 
     private Set<String> buildDependencyClasses( MavenProject project )
         throws IOException
     {
 
         String outputDirectory = project.getBuild().getOutputDirectory();
         Set<String> dependencyClasses = new HashSet<>( buildDependencyClasses( outputDirectory ) );
 
         String testOutputDirectory = project.getBuild().getTestOutputDirectory();
         dependencyClasses.addAll( buildDependencyClasses( testOutputDirectory ) );
 
         return dependencyClasses;
     }
     
     private Set<String> buildMainDependencyClasses( MavenProject project )
                     throws IOException
     {
 
         String outputDirectory = project.getBuild().getOutputDirectory();
         Set<String> dependencyClasses = new HashSet<>( buildDependencyClasses( outputDirectory ) );
 
         return dependencyClasses;
     }
 
     private Set<String> buildDependencyClasses( String path )
         throws IOException
     {
         URL url = new File( path ).toURI().toURL();
 
         return dependencyAnalyzer.analyze( url );
     }
 
     private Set<Artifact> buildDeclaredArtifacts( MavenProject project )
     {
         Set<Artifact> declaredArtifacts = project.getDependencyArtifacts();
 
         if ( declaredArtifacts == null )
         {
             declaredArtifacts = Collections.emptySet();
         }
 
         return declaredArtifacts;
     }
 
     private Map<Artifact, Set<String>> buildUsedArtifacts( Map<Artifact, Set<String>> artifactClassMap,
                                               Set<String> dependencyClasses )
     {
         Map<Artifact, Set<String>> usedArtifacts = new HashMap<>();
 
         for ( String className : dependencyClasses )
         {
             Artifact artifact = findArtifactForClassName( artifactClassMap, className );
 
             if ( artifact != null )
             {
                 Set<String> classesFromArtifact = usedArtifacts.get( artifact );
                 if ( classesFromArtifact == null )
                 {
                     classesFromArtifact = new HashSet<String>();
                     usedArtifacts.put( artifact, classesFromArtifact );
                 }
                 classesFromArtifact.add( className );
             }
         }
 
         return usedArtifacts;
     }
 
     private Artifact findArtifactForClassName( Map<Artifact, Set<String>> artifactClassMap, String className )
     {
         for ( Map.Entry<Artifact, Set<String>> entry : artifactClassMap.entrySet() )
         {
             if ( entry.getValue().contains( className ) )
             {
                 return entry.getKey();
             }
         }
 
         return null;
     }
 }