/*

  * This file is part of dependency-check-core.

  *

  * Dependency-check-core is free software: you can redistribute it and/or modify it

  * under the terms of the GNU General Public License as published by the Free

  * Software Foundation, either version 3 of the License, or (at your option) any

  * later version.

  *

  * Dependency-check-core is distributed in the hope that it will be useful, but

  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more

  * details.

  *

  * You should have received a copy of the GNU General Public License along with

  * dependency-check-core. If not, see http://www.gnu.org/licenses/.

  *

  * Copyright (c) 2012 Jeremy Long. All Rights Reserved.

  */

 package org.owasp.dependencycheck;

 import java.util.EnumMap;

 import java.io.File;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.HashSet;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Set;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import org.owasp.dependencycheck.analyzer.AnalysisException;

 import org.owasp.dependencycheck.analyzer.AnalysisPhase;

 import org.owasp.dependencycheck.analyzer.Analyzer;

 import org.owasp.dependencycheck.analyzer.AnalyzerService;

 import org.owasp.dependencycheck.data.CachedWebDataSource;

 import org.owasp.dependencycheck.data.NoDataException;

 import org.owasp.dependencycheck.data.UpdateException;

 import org.owasp.dependencycheck.data.UpdateService;

 import org.owasp.dependencycheck.data.cpe.CpeIndexReader;

 import org.owasp.dependencycheck.dependency.Dependency;

 import org.owasp.dependencycheck.utils.FileUtils;

 import org.owasp.dependencycheck.utils.InvalidSettingException;

 import org.owasp.dependencycheck.utils.Settings;

 /**

  * Scans files, directories, etc. for Dependencies. Analyzers are loaded and

  * used to process the files found by the scan, if a file is encountered and an

  * Analyzer is associated with the file type then the file is turned into a

  * dependency.

  *

  * @author Jeremy Long (jeremy.long@owasp.org)

  */

 public class Engine {

     /**

      * The list of dependencies.

      */

     private final List<Dependency> dependencies = new ArrayList<Dependency>();

     /**

      * A Map of analyzers grouped by Analysis phase.

      */

     private final EnumMap<AnalysisPhase, List<Analyzer>> analyzers =

             new EnumMap<AnalysisPhase, List<Analyzer>>(AnalysisPhase.class);

     /**

      * A set of extensions supported by the analyzers.

      */

     private final Set<String> extensions = new HashSet<String>();

     /**

      * Creates a new Engine.

      */

     public Engine() {

         boolean autoUpdate = true;

         try {

             autoUpdate = Settings.getBoolean(Settings.KEYS.AUTO_UPDATE);

         } catch (InvalidSettingException ex) {

             Logger.getLogger(Engine.class.getName()).log(Level.FINE, "Invalid setting for auto-update; using true.");

         }

         if (autoUpdate) {

             doUpdates();

         }

         loadAnalyzers();

     }

     /**

      * Creates a new Engine.

      *

      * @param autoUpdate indicates whether or not data should be updated from

      * the Internet

      * @deprecated This function should no longer be used; the autoupdate flag

      * should be set using:

      * <code>Settings.setBoolean(Settings.KEYS.AUTO_UPDATE, value);</code>

      */

     @Deprecated

     public Engine(boolean autoUpdate) {

         if (autoUpdate) {

             doUpdates();

         }

         loadAnalyzers();

     }

     /**

      * Loads the analyzers specified in the configuration file (or system

      * properties).

      */

     private void loadAnalyzers() {

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             analyzers.put(phase, new ArrayList<Analyzer>());

         }

         final AnalyzerService service = AnalyzerService.getInstance();

         final Iterator<Analyzer> iterator = service.getAnalyzers();

         while (iterator.hasNext()) {

             final Analyzer a = iterator.next();

             analyzers.get(a.getAnalysisPhase()).add(a);

             if (a.getSupportedExtensions() != null) {

                 extensions.addAll(a.getSupportedExtensions());

             }

         }

     }

     /**

      * Get the List of the analyzers for a specific phase of analysis.

      *

      * @param phase the phase to get the configured analyzers.

      * @return the analyzers loaded

      */

     public List<Analyzer> getAnalyzers(AnalysisPhase phase) {

         return analyzers.get(phase);

     }

     /**

      * Get the dependencies identified.

      *

      * @return the dependencies identified

      */

     public List<Dependency> getDependencies() {

         return dependencies;

     }

     /**

      * Scans an array of files or directories. If a directory is specified, it

      * will be scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @since v0.3.2.5

      *

      * @param paths an array of paths to files or directories to be analyzed.

      */

     public void scan(String[] paths) {

         for (String path : paths) {

             final File file = new File(path);

             scan(file);

         }

     }

     /**

      * Scans a given file or directory. If a directory is specified, it will be

      * scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @param path the path to a file or directory to be analyzed.

      */

     public void scan(String path) {

         final File file = new File(path);

         scan(file);

     }

     /**

      * Scans an array of files or directories. If a directory is specified, it

      * will be scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @since v0.3.2.5

      *

      * @param files an array of paths to files or directories to be analyzed.

      */

     public void scan(File[] files) {

         for (File file : files) {

             scan(file);

         }

     }

     /**

      * Scans a list of files or directories. If a directory is specified, it

      * will be scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @since v0.3.2.5

      *

      * @param files a set of paths to files or directories to be analyzed.

      */

     public void scan(Set<File> files) {

         for (File file : files) {

             scan(file);

         }

     }

     /**

      * Scans a list of files or directories. If a directory is specified, it

      * will be scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @since v0.3.2.5

      *

      * @param files a set of paths to files or directories to be analyzed.

      */

     public void scan(List<File> files) {

         for (File file : files) {

             scan(file);

         }

     }

     /**

      * Scans a given file or directory. If a directory is specified, it will be

      * scanned recursively. Any dependencies identified are added to the

      * dependency collection.

      *

      * @since v0.3.2.4

      *

      * @param file the path to a file or directory to be analyzed.

      */

     public void scan(File file) {

         if (file.exists()) {

             if (file.isDirectory()) {

                 scanDirectory(file);

             } else {

                 scanFile(file);

             }

         }

     }

     /**

      * Recursively scans files and directories. Any dependencies identified are

      * added to the dependency collection.

      *

      * @param dir the directory to scan.

      */

     protected void scanDirectory(File dir) {

         final File[] files = dir.listFiles();

         if (files != null) {

             for (File f : files) {

                 if (f.isDirectory()) {

                     scanDirectory(f);

                 } else {

                     scanFile(f);

                 }

             }

         }

     }

     /**

      * Scans a specified file. If a dependency is identified it is added to the

      * dependency collection.

      *

      * @param file The file to scan.

      */

     protected void scanFile(File file) {

         if (!file.isFile()) {

             final String msg = String.format("Path passed to scanFile(File) is not a file: %s. Skipping the file.", file.toString());

             Logger.getLogger(Engine.class.getName()).log(Level.FINE, msg);

             return;

         }

         final String fileName = file.getName();

         final String extension = FileUtils.getFileExtension(fileName);

         if (extension != null) {

             if (extensions.contains(extension)) {

                 final Dependency dependency = new Dependency(file);

                 dependencies.add(dependency);

             }

         } else {

             final String msg = String.format("No file extension found on file '%s'. The file was not analyzed.",

                     file.toString());

             Logger.getLogger(Engine.class.getName()).log(Level.FINEST, msg);

         }

     }

     /**

      * Runs the analyzers against all of the dependencies.

      */

     public void analyzeDependencies() {

         //need to ensure that data exists

         try {

             ensureDataExists();

         } catch (NoDataException ex) {

             final String msg = String.format("%n%n%s%n%nUnable to continue dependency-check analysis.", ex.getMessage());

             Logger.getLogger(Engine.class.getName()).log(Level.SEVERE, msg);

             Logger.getLogger(Engine.class.getName()).log(Level.FINE, null, ex);

             return;

         }

         //phase one initialize

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             final List<Analyzer> analyzerList = analyzers.get(phase);

             for (Analyzer a : analyzerList) {

                 try {

                     final String msg = String.format("Initializing %s", a.getName());

                     Logger.getLogger(Engine.class.getName()).log(Level.FINE, msg);

                     a.initialize();

                 } catch (Exception ex) {

                     final String msg = String.format("Exception occurred initializing %s.", a.getName());

                     Logger.getLogger(Engine.class.getName()).log(Level.SEVERE, msg);

                     Logger.getLogger(Engine.class.getName()).log(Level.INFO, null, ex);

                     try {

                         a.close();

                     } catch (Exception ex1) {

                         Logger.getLogger(Engine.class.getName()).log(Level.FINEST, null, ex1);

                     }

                 }

             }

         }

         // analysis phases

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             final List<Analyzer> analyzerList = analyzers.get(phase);

             for (Analyzer a : analyzerList) {

                 /* need to create a copy of the collection because some of the

                  * analyzers may modify it. This prevents ConcurrentModificationExceptions.

                  * This is okay for adds/deletes because it happens per analyzer.

                  */

                 final String msg = String.format("Begin Analyzer '%s'", a.getName());

                 Logger.getLogger(Engine.class.getName()).log(Level.FINE, msg);

                 final Set<Dependency> dependencySet = new HashSet<Dependency>();

                 dependencySet.addAll(dependencies);

                 for (Dependency d : dependencySet) {

                     final String msgFile = String.format("Begin Analysis of '%s'", d.getActualFilePath());

                     Logger.getLogger(Engine.class.getName()).log(Level.FINE, msgFile);

                     if (a.supportsExtension(d.getFileExtension())) {

                         try {

                             a.analyze(d, this);

                         } catch (AnalysisException ex) {

                             d.addAnalysisException(ex);

                         }

                     }

                 }

             }

         }

         //close/cleanup

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             final List<Analyzer> analyzerList = analyzers.get(phase);

             for (Analyzer a : analyzerList) {

                 final String msg = String.format("Closing Analyzer '%s'", a.getName());

                 Logger.getLogger(Engine.class.getName()).log(Level.FINE, msg);

                 try {

                     a.close();

                 } catch (Exception ex) {

                     Logger.getLogger(Engine.class.getName()).log(Level.FINEST, null, ex);

                 }

             }

         }

     }

     /**

      * Cycles through the cached web data sources and calls update on all of

      * them.

      */

     private void doUpdates() {

         final UpdateService service = UpdateService.getInstance();

         final Iterator<CachedWebDataSource> iterator = service.getDataSources();

         while (iterator.hasNext()) {

             final CachedWebDataSource source = iterator.next();

             try {

                 source.update();

             } catch (UpdateException ex) {

                 Logger.getLogger(Engine.class.getName()).log(Level.WARNING,

                         "Unable to update Cached Web DataSource, using local data instead. Results may not include recent vulnerabilities.");

                 Logger.getLogger(Engine.class.getName()).log(Level.FINE,

                         String.format("Unable to update details for %s", source.getClass().getName()), ex);

             }

         }

     }

     /**

      * Returns a full list of all of the analyzers. This is useful for reporting

      * which analyzers where used.

      *

      * @return a list of Analyzers

      */

     public List<Analyzer> getAnalyzers() {

         final List<Analyzer> ret = new ArrayList<Analyzer>();

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             final List<Analyzer> analyzerList = analyzers.get(phase);

             ret.addAll(analyzerList);

         }

         return ret;

     }

     /**

      * Checks all analyzers to see if an extension is supported.

      *

      * @param ext a file extension

      * @return true or false depending on whether or not the file extension is

      * supported

      */

     public boolean supportsExtension(String ext) {

         if (ext == null) {

             return false;

         }

         for (AnalysisPhase phase : AnalysisPhase.values()) {

             final List<Analyzer> analyzerList = analyzers.get(phase);

             for (Analyzer a : analyzerList) {

                 if (a.getSupportedExtensions() != null && a.supportsExtension(ext)) {

                     return true;

                 }

             }

         }

         return false;

     }

     /**

      * Checks the CPE Index to ensure documents exists. If none exist a

      * NoDataException is thrown.

      *

      * @throws NoDataException thrown if no data exists in the CPE Index

      */

     private void ensureDataExists() throws NoDataException {

         CpeIndexReader cpe = null;

         boolean noDataExists = false;

         try {

             cpe = new CpeIndexReader();

             cpe.open();

             if (cpe.numDocs() <= 0) {

                 noDataExists = true;

             }

         } catch (IOException ex) {

             noDataExists = true;

         } catch (NullPointerException ex) {

             noDataExists = true;

         } finally {

             if (cpe != null) {

                 cpe.close();

             }

         }

         if (noDataExists) {

             throw new NoDataException("No data exists in the data store. Please check that you are able to connect "

                     + "to the Internet and re-run dependency-check. If the problem persists determine whether you need "

                     + "to set a proxy url and port.\\n\\nIf you are unable to solve this problem please contact the mailing "

                     + "list for help: dependency-check@googlegroups.com");

         }

     }

 }