/*

  * 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.data.update;

 import java.io.File;

 import java.io.IOException;

 import org.owasp.dependencycheck.data.CachedWebDataSource;

 import java.net.MalformedURLException;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import org.owasp.dependencycheck.concurrency.DirectoryLockException;

 import org.owasp.dependencycheck.concurrency.DirectorySpinLock;

 import org.owasp.dependencycheck.concurrency.InvalidDirectoryException;

 import org.owasp.dependencycheck.data.UpdateException;

 import org.owasp.dependencycheck.utils.DownloadFailedException;

 import org.owasp.dependencycheck.utils.FileUtils;

 import org.owasp.dependencycheck.utils.Settings;

 /**

  * Class responsible for updating the CPE and NVDCVE data stores.

  *

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

  */

 public class DatabaseUpdater implements CachedWebDataSource {

     /**

      * <p>Downloads the latest NVD CVE XML file from the web and imports it into

      * the current CVE Database.</p>

      *

      * @throws UpdateException is thrown if there is an error updating the

      * database

      */

     @Override

     public void update() throws UpdateException {

         final File dataDir = Settings.getFile(Settings.KEYS.DATA_DIRECTORY);

         DirectorySpinLock lock = null;

         try {

             lock = new DirectorySpinLock(dataDir);

         } catch (InvalidDirectoryException ex) {

             throw new UpdateException("Unable to obtain lock on the data directory", ex);

         } catch (DirectoryLockException ex) {

             throw new UpdateException("Unable to obtain exclusive lock on the data directory", ex);

         }

         try {

             lock.obtainSharedLock();

             final UpdateTask task = UpdateTaskFactory.getUpdateTask();

             if (task.isUpdateNeeded()) {

                 lock.release();

                 lock.obtainExclusiveLock();

                 if (task.shouldDeleteAndRecreate()) {

                     try {

                         deleteExistingData();

                     } catch (IOException ex) {

                         Logger.getLogger(DatabaseUpdater.class.getName()).log(Level.WARNING, "Unable to delete the existing data directory");

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

                     }

                 }

                 task.update();

             }

         } catch (DirectoryLockException ex) {

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

                     "Unable to obtain lock on data directory, unable to update the data to use the most current data.");

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

         } catch (MalformedURLException ex) {

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

                     "NVD CVE properties files contain an invalid URL, unable to update the data to use the most current data.");

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

         } catch (DownloadFailedException ex) {

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

                     "Unable to download the NVD CVE data, unable to update the data to use the most current data.");

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

         } finally {

             if (lock != null) {

                 lock.release();

             }

         }

     }

     /**

      * Deletes the existing data directories.

      *

      * @throws IOException thrown if the directory cannot be deleted

      */

     protected void deleteExistingData() throws IOException {

         File data = Settings.getFile(Settings.KEYS.CVE_DATA_DIRECTORY);

         if (data.exists()) {

             FileUtils.delete(data);

         }

         data = Settings.getFile(Settings.KEYS.CPE_DATA_DIRECTORY);

         if (data.exists()) {

             FileUtils.delete(data);

         }

         data = DataStoreMetaInfo.getPropertiesFile();

         if (data.exists()) {

             FileUtils.delete(data);

         }

     }

 }