/*
    * This file is part of dependency-check-maven.
    *
    * Licensed 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.
   *
   * Copyright (c) 2013 Jeremy Long. All Rights Reserved.
   */
  package org.owasp.dependencycheck.maven;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Locale;
  import java.util.Set;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugins.annotations.LifecyclePhase;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.plugins.annotations.ResolutionScope;
  import org.apache.maven.project.MavenProject;
  import org.owasp.dependencycheck.analyzer.DependencyBundlingAnalyzer;
  import org.owasp.dependencycheck.analyzer.exception.AnalysisException;
  import org.owasp.dependencycheck.data.nvdcve.DatabaseException;
  import org.owasp.dependencycheck.dependency.Dependency;
  import org.owasp.dependencycheck.exception.ExceptionCollection;
  import org.owasp.dependencycheck.exception.ReportException;
  import org.owasp.dependencycheck.utils.Settings;
  
  /**
   * Maven Plugin that checks project dependencies and the dependencies of all
   * child modules to see if they have any known published vulnerabilities.
   *
   * @author Jeremy Long
   */
  @Mojo(
          name = "aggregate",
          defaultPhase = LifecyclePhase.VERIFY,
          /*aggregator = true,*/
          threadSafe = false,
          requiresDependencyResolution = ResolutionScope.COMPILE_PLUS_RUNTIME,
          requiresOnline = true
  )
  public class AggregateMojo extends BaseDependencyCheckMojo {
  
      /**
       * The key to store aggregate exception in the root Maven execution context.
       */
      private static final String AGGREGATE_EXCEPTIONS = "AggregateExceptions";
  
      /**
       * Executes the aggregate dependency-check goal. This runs dependency-check
       * and generates the subsequent reports.
       *
       * @throws MojoExecutionException thrown if there is ane exception running
       * the mojo
       * @throws MojoFailureException thrown if dependency-check is configured to
       * fail the build
       */
      @Override
      public void runCheck() throws MojoExecutionException, MojoFailureException {
          final MavenEngine engine = generateDataFile();
          if (engine == null) {
              return;
          }
  
          if (getProject() == getLastProject()) {
              //ensure that the .ser file was created for each.
              for (MavenProject current : getReactorProjects()) {
                  final File dataFile = getDataFile(current);
                  if (dataFile == null && !skipProject(current)) { //dc was never run on this project. write the ser to the target.
                      getLog().error(String.format("Module '%s' did not execute dependency-check; an attempt will be made to perform "
                              + "the check but dependencies may be missed resulting in false negatives.", current.getName()));
                      generateDataFile(engine, current);
                  }
              }
              for (MavenProject current : getReactorProjects()) {
                  List<Dependency> dependencies = readDataFile(current);
                  if (dependencies == null) {
                      dependencies = new ArrayList<Dependency>();
                  }
                  final Set<MavenProject> childProjects = getDescendants(current);
                  for (MavenProject reportOn : childProjects) {
                      final List<Dependency> childDeps = readDataFile(reportOn);
                      if (childDeps != null && !childDeps.isEmpty()) {
                          if (getLog().isDebugEnabled()) {
                             getLog().debug(String.format("Adding %d dependencies from %s", childDeps.size(), reportOn.getName()));
                         }
                         dependencies.addAll(childDeps);
                     } else if (getLog().isDebugEnabled()) {
                         getLog().debug(String.format("No dependencies read for %s", reportOn.getName()));
                     }
                 }
                 engine.getDependencies().clear();
                 engine.getDependencies().addAll(dependencies);
                 final DependencyBundlingAnalyzer bundler = new DependencyBundlingAnalyzer();
                 try {
                     if (getLog().isDebugEnabled()) {
                         getLog().debug(String.format("Dependency count pre-bundler: %s", engine.getDependencies().size()));
                     }
                     bundler.analyze(null, engine);
                     if (getLog().isDebugEnabled()) {
                         getLog().debug(String.format("Dependency count post-bundler: %s", engine.getDependencies().size()));
                     }
                 } catch (AnalysisException ex) {
                     getLog().warn("An error occurred grouping the dependencies; duplicate entries may exist in the report", ex);
                     getLog().debug("Bundling Exception", ex);
                 }
 
                 File outputDir = getCorrectOutputDirectory(current);
                 if (outputDir == null) {
                     //in some regards we shouldn't be writting this, but we are anyway.
                     //we shouldn't write this because nothing is configured to generate this report.
                     outputDir = new File(current.getBuild().getDirectory());
                 }
                 try {
                     writeReports(engine, current, outputDir);
                 } catch (ReportException ex) {
                     ExceptionCollection exCol = (ExceptionCollection) engine.getExecutionRoot().getContextValue(AGGREGATE_EXCEPTIONS);
                     if (exCol == null) {
                         exCol = new ExceptionCollection("Error writing aggregate report", ex);
                     } else {
                         exCol.addException(ex);
                     }
                     if (this.isFailOnError()) {
                         throw new MojoExecutionException("One or more exceptions occured during dependency-check analysis", exCol);
                     } else {
                         getLog().debug("One or more exceptions occured during dependency-check analysis", exCol);
                     }
                 }
             }
         }
         engine.cleanup();
         Settings.cleanup();
     }
 
     /**
      * Gets the last project in the reactor - taking into account skipped
      * projects.
      *
      * @return the last project in the reactor
      */
     private MavenProject getLastProject() {
         for (int x = getReactorProjects().size() - 1; x >= 0; x--) {
             final MavenProject p = getReactorProjects().get(x);
             if (!skipProject(p)) {
                 return p;
             }
         }
         return null;
     }
 
     /**
      * Tests if the project is being skipped in the Maven site report.
      *
      * @param project a project in the reactor
      * @return true if the project is skipped; otherwise false
      */
     private boolean skipProject(MavenProject project) {
         final String skip = (String) project.getProperties().get("maven.site.skip");
         return "true".equalsIgnoreCase(skip) && isGeneratingSite();
     }
 
     /**
      * Returns a set containing all the descendant projects of the given
      * project.
      *
      * @param project the project for which all descendants will be returned
      * @return the set of descendant projects
      */
     protected Set<MavenProject> getDescendants(MavenProject project) {
         if (project == null) {
             return Collections.emptySet();
         }
         final Set<MavenProject> descendants = new HashSet<MavenProject>();
         int size = 0;
         if (getLog().isDebugEnabled()) {
             getLog().debug(String.format("Collecting descendants of %s", project.getName()));
         }
         for (String m : project.getModules()) {
             for (MavenProject mod : getReactorProjects()) {
                 try {
                     File mpp = new File(project.getBasedir(), m);
                     mpp = mpp.getCanonicalFile();
                     if (mpp.compareTo(mod.getBasedir()) == 0 && descendants.add(mod)
                             && getLog().isDebugEnabled()) {
                         getLog().debug(String.format("Decendent module %s added", mod.getName()));
 
                     }
                 } catch (IOException ex) {
                     if (getLog().isDebugEnabled()) {
                         getLog().debug("Unable to determine module path", ex);
                     }
                 }
             }
         }
         do {
             size = descendants.size();
             for (MavenProject p : getReactorProjects()) {
                 if (project.equals(p.getParent()) || descendants.contains(p.getParent())) {
                     if (descendants.add(p) && getLog().isDebugEnabled()) {
                         getLog().debug(String.format("Decendent %s added", p.getName()));
 
                     }
                     for (MavenProject modTest : getReactorProjects()) {
                         if (p.getModules() != null && p.getModules().contains(modTest.getName())
                                 && descendants.add(modTest)
                                 && getLog().isDebugEnabled()) {
                             getLog().debug(String.format("Decendent %s added", modTest.getName()));
                         }
                     }
                 }
                 final Set<MavenProject> addedDescendants = new HashSet<MavenProject>();
                 for (MavenProject dec : descendants) {
                     for (String mod : dec.getModules()) {
                         try {
                             File mpp = new File(dec.getBasedir(), mod);
                             mpp = mpp.getCanonicalFile();
                             if (mpp.compareTo(p.getBasedir()) == 0) {
                                 addedDescendants.add(p);
                             }
                         } catch (IOException ex) {
                             if (getLog().isDebugEnabled()) {
                                 getLog().debug("Unable to determine module path", ex);
                             }
                         }
                     }
                 }
                 for (MavenProject addedDescendant : addedDescendants) {
                     if (descendants.add(addedDescendant) && getLog().isDebugEnabled()) {
                         getLog().debug(String.format("Decendent module %s added", addedDescendant.getName()));
                     }
                 }
             }
         } while (size != 0 && size != descendants.size());
         if (getLog().isDebugEnabled()) {
             getLog().debug(String.format("%s has %d children", project, descendants.size()));
         }
         return descendants;
     }
 
     /**
      * Test if the project has pom packaging
      *
      * @param mavenProject Project to test
      * @return <code>true</code> if it has a pom packaging; otherwise
      * <code>false</code>
      */
     protected boolean isMultiModule(MavenProject mavenProject) {
         return "pom".equals(mavenProject.getPackaging());
     }
 
     /**
      * Initializes the engine, runs a scan, and writes the serialized
      * dependencies to disk.
      *
      * @return the MavenEngine used to execute dependency-check
      * @throws MojoExecutionException thrown if there is an exception running
      * the mojo
      * @throws MojoFailureException thrown if dependency-check is configured to
      * fail the build if severe CVEs are identified.
      */
     protected MavenEngine generateDataFile() throws MojoExecutionException, MojoFailureException {
         MavenEngine engine = null;
         try {
             engine = initializeEngine();
         } catch (DatabaseException ex) {
             if (getLog().isDebugEnabled()) {
                 getLog().debug("Database connection error", ex);
             }
             final String msg = "An exception occured connecting to the local database. Please see the log file for more details.";
             if (this.isFailOnError()) {
                 throw new MojoExecutionException(msg, ex);
             }
             getLog().error(msg, ex);
             return null;
         }
         return generateDataFile(engine, getProject());
     }
 
     /**
      * Runs dependency-check's MavenEngine and writes the serialized
      * dependencies to disk.
      *
      * @param engine the MavenEngine to use when scanning.
      * @param project the project to scan and generate the data file for
      * @return the MavenEngine used to execute dependency-check
      * @throws MojoExecutionException thrown if there is an exception running
      * the mojo
      * @throws MojoFailureException thrown if dependency-check is configured to
      * fail the build if severe CVEs are identified.
      */
     protected MavenEngine generateDataFile(MavenEngine engine, MavenProject project) throws MojoExecutionException, MojoFailureException {
         if (getLog().isDebugEnabled()) {
             getLog().debug(String.format("Begin Scanning: %s", project.getName()));
         }
         engine.getDependencies().clear();
         engine.resetFileTypeAnalyzers();
         scanArtifacts(project, engine);
         try {
             engine.analyzeDependencies();
         } catch (ExceptionCollection ex) {
             ExceptionCollection col = (ExceptionCollection) engine.getExecutionRoot().getContextValue(AGGREGATE_EXCEPTIONS);
             if (col == null) {
                 col = ex;
             } else if (ex.isFatal()) {
                 col.setFatal(true);
                 col.getExceptions().addAll(ex.getExceptions());
             }
             if (col.isFatal()) {
                 final String msg = String.format("Fatal exception(s) analyzing %s", project.getName());
                 if (this.isFailOnError()) {
                     throw new MojoExecutionException(msg, ex);
                 }
                 getLog().error(msg, col);
                 return null;
             } else {
                 final String msg = String.format("Exception(s) analyzing %s", project.getName());
                 if (getLog().isDebugEnabled()) {
                     getLog().debug(msg, ex);
                 }
                 engine.getExecutionRoot().setContextValue(AGGREGATE_EXCEPTIONS, col);
             }
         }
         final File target = new File(project.getBuild().getDirectory());
         writeDataFile(project, target, engine.getDependencies());
         showSummary(project, engine.getDependencies());
         checkForFailure(engine.getDependencies());
         return engine;
     }
 
     @Override
     public boolean canGenerateReport() {
         return true; //aggregate always returns true for now - we can look at a more complicated/acurate solution later
     }
 
     /**
      * The name of the report in the site.
      */
     @SuppressWarnings("CanBeFinal")
     @Parameter(property = "name", defaultValue = "dependency-check:aggregate", required = true)
     private String name = "dependency-check:aggregate";
 
     /**
      * Returns the report name.
      *
      * @param locale the location
      * @return the report name
      */
     @Override
     public String getName(Locale locale) {
         return name;
     }
 
     /**
      * Gets the description of the Dependency-Check report to be displayed in
      * the Maven Generated Reports page.
      *
      * @param locale The Locale to get the description for
      * @return the description
      */
     @Override
     public String getDescription(Locale locale) {
         return "Generates an aggregate report of all child Maven projects providing details on any "
                 + "published vulnerabilities within project dependencies. This report is a best "
                 + "effort and may contain false positives and false negatives.";
     }
 }