/*
    * This file is part of dependency-check-cli.
    *
    * Dependency-check-cli 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-cli 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-cli. If not, see http://www.gnu.org/licenses/.
   *
   * Copyright (c) 2012 Jeremy Long. All Rights Reserved.
   */
  package org.owasp.dependencycheck.cli;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import org.apache.commons.cli.CommandLine;
  import org.apache.commons.cli.CommandLineParser;
  import org.apache.commons.cli.HelpFormatter;
  import org.apache.commons.cli.Option;
  import org.apache.commons.cli.OptionBuilder;
  import org.apache.commons.cli.OptionGroup;
  import org.apache.commons.cli.Options;
  import org.apache.commons.cli.ParseException;
  import org.apache.commons.cli.PosixParser;
  import org.owasp.dependencycheck.reporting.ReportGenerator.Format;
  import org.owasp.dependencycheck.utils.Settings;
  
  /**
   * A utility to parse command line arguments for the DependencyCheck.
   *
   * @author Jeremy Long (jeremy.long@owasp.org)
   */
  public final class CliParser {
  
      /**
       * The command line.
       */
      private CommandLine line;
      /**
       * The options for the command line parser.
       */
      private final Options options = createCommandLineOptions();
      /**
       * Indicates whether the arguments are valid.
       */
      private boolean isValid = true;
  
      /**
       * Parses the arguments passed in and captures the results for later use.
       *
       * @param args the command line arguments
       * @throws FileNotFoundException is thrown when a 'file' argument does not
       * point to a file that exists.
       * @throws ParseException is thrown when a Parse Exception occurs.
       */
      public void parse(String[] args) throws FileNotFoundException, ParseException {
          line = parseArgs(args);
  
          if (line != null) {
              validateArgs();
          }
      }
  
      /**
       * Parses the command line arguments.
       *
       * @param args the command line arguments
       * @return the results of parsing the command line arguments
       * @throws ParseException if the arguments are invalid
       */
      private CommandLine parseArgs(String[] args) throws ParseException {
          final CommandLineParser parser = new PosixParser();
          return parser.parse(options, args);
      }
  
      /**
       * Validates that the command line arguments are valid.
       *
       * @throws FileNotFoundException if there is a file specified by either the
       * SCAN or CPE command line arguments that does not exist.
       * @throws ParseException is thrown if there is an exception parsing the
       * command line.
       */
      private void validateArgs() throws FileNotFoundException, ParseException {
          if (isRunScan()) {
              validatePathExists(getScanFiles(), "scan");
              validatePathExists(getReportDirectory(), "out");
              if (!line.hasOption(ArgumentName.APP_NAME)) {
                  throw new ParseException("Missing 'app' argument; the scan cannot be run without the an application name.");
              }
              if (line.hasOption(ArgumentName.OUTPUT_FORMAT)) {
                  final String format = line.getOptionValue(ArgumentName.OUTPUT_FORMAT);
                 try {
                     Format.valueOf(format);
                 } catch (IllegalArgumentException ex) {
                     final String msg = String.format("An invalid 'format' of '%s' was specified. Supported output formats are XML, HTML, VULN, or ALL", format);
                     throw new ParseException(msg);
                 }
             }
         }
     }
 
     /**
      * Validates whether or not the path(s) points at a file that exists; if the
      * path(s) does not point to an existing file a FileNotFoundException is
      * thrown.
      *
      * @param paths the paths to validate if they exists
      * @param optType the option being validated (e.g. scan, out, etc.)
      * @throws FileNotFoundException is thrown if one of the paths being
      * validated does not exist.
      */
     private void validatePathExists(String[] paths, String optType) throws FileNotFoundException {
         for (String path : paths) {
             validatePathExists(path, optType);
         }
     }
 
     /**
      * Validates whether or not the path points at a file that exists; if the
      * path does not point to an existing file a FileNotFoundException is
      * thrown.
      *
      * @param path the paths to validate if they exists
      * @param optType the option being validated (e.g. scan, out, etc.)
      * @throws FileNotFoundException is thrown if the path being validated does
      * not exist.
      */
     private void validatePathExists(String path, String optType) throws FileNotFoundException {
         final File f = new File(path);
         if (!f.exists()) {
             isValid = false;
             final String msg = String.format("Invalid '%s' argument: '%s'", optType, path);
             throw new FileNotFoundException(msg);
         }
     }
 
     /**
      * Generates an Options collection that is used to parse the command line
      * and to display the help message.
      *
      * @return the command line options used for parsing the command line
      */
     @SuppressWarnings("static-access")
     private Options createCommandLineOptions() {
         final Option help = new Option(ArgumentName.HELP_SHORT, ArgumentName.HELP, false,
                 "Print this message.");
 
         final Option version = new Option(ArgumentName.VERSION_SHORT, ArgumentName.VERSION,
                 false, "Print the version information.");
 
         final Option noUpdate = new Option(ArgumentName.DISABLE_AUTO_UPDATE_SHORT, ArgumentName.DISABLE_AUTO_UPDATE,
                 false, "Disables the automatic updating of the CPE data.");
 
         final Option appName = OptionBuilder.withArgName("name").hasArg().withLongOpt(ArgumentName.APP_NAME)
                 .withDescription("The name of the application being scanned. This is a required argument.")
                 .create(ArgumentName.APP_NAME_SHORT);
 
         final Option connectionTimeout = OptionBuilder.withArgName("timeout").hasArg().withLongOpt(ArgumentName.CONNECTION_TIMEOUT)
                 .withDescription("The connection timeout (in milliseconds) to use when downloading resources.")
                 .create(ArgumentName.CONNECTION_TIMEOUT_SHORT);
 
         final Option proxyUrl = OptionBuilder.withArgName("url").hasArg().withLongOpt(ArgumentName.PROXY_URL)
                 .withDescription("The proxy url to use when downloading resources.")
                 .create(ArgumentName.PROXY_URL_SHORT);
 
         final Option proxyPort = OptionBuilder.withArgName("port").hasArg().withLongOpt(ArgumentName.PROXY_PORT)
                 .withDescription("The proxy port to use when downloading resources.")
                 .create(ArgumentName.PROXY_PORT_SHORT);
 
         final Option path = OptionBuilder.withArgName("path").hasArg().withLongOpt(ArgumentName.SCAN)
                 .withDescription("The path to scan - this option can be specified multiple times.")
                 .create(ArgumentName.SCAN_SHORT);
 
         final Option props = OptionBuilder.withArgName("file").hasArg().withLongOpt(ArgumentName.PROP)
                 .withDescription("A property file to load.")
                 .create(ArgumentName.PROP_SHORT);
 
         final Option data = OptionBuilder.withArgName("path").hasArg().withLongOpt(ArgumentName.DATA_DIRECTORY)
                 .withDescription("The location of the data directory used to store persistent data. This option should generally not be set.")
                 .create(ArgumentName.DATA_DIRECTORY_SHORT);
 
         final Option out = OptionBuilder.withArgName("folder").hasArg().withLongOpt(ArgumentName.OUT)
                 .withDescription("The folder to write reports to. This defaults to the current directory.")
                 .create(ArgumentName.OUT_SHORT);
 
         final Option outputFormat = OptionBuilder.withArgName("format").hasArg().withLongOpt(ArgumentName.OUTPUT_FORMAT)
                 .withDescription("The output format to write to (XML, HTML, VULN, ALL). The default is HTML.")
                 .create(ArgumentName.OUTPUT_FORMAT_SHORT);
 
         final OptionGroup og = new OptionGroup();
         og.addOption(path);
 
         final Options opts = new Options();
         opts.addOptionGroup(og);
         opts.addOption(out);
         opts.addOption(outputFormat);
         opts.addOption(appName);
         opts.addOption(version);
         opts.addOption(help);
         opts.addOption(noUpdate);
         opts.addOption(props);
         opts.addOption(data);
         opts.addOption(proxyPort);
         opts.addOption(proxyUrl);
         opts.addOption(connectionTimeout);
 
         return opts;
     }
 
     /**
      * Determines if the 'version' command line argument was passed in.
      *
      * @return whether or not the 'version' command line argument was passed in
      */
     public boolean isGetVersion() {
         return (line != null) && line.hasOption(ArgumentName.VERSION);
     }
 
     /**
      * Determines if the 'help' command line argument was passed in.
      *
      * @return whether or not the 'help' command line argument was passed in
      */
     public boolean isGetHelp() {
         return (line != null) && line.hasOption(ArgumentName.HELP);
     }
 
     /**
      * Determines if the 'scan' command line argument was passed in.
      *
      * @return whether or not the 'scan' command line argument was passed in
      */
     public boolean isRunScan() {
         return (line != null) && isValid && line.hasOption(ArgumentName.SCAN);
     }
 
     /**
      * Displays the command line help message to the standard output.
      */
     public void printHelp() {
         final HelpFormatter formatter = new HelpFormatter();
         final String nl = System.getProperty("line.separator");
 
         formatter.printHelp(Settings.getString("application.name", "DependencyCheck"),
                 nl + Settings.getString("application.name", "DependencyCheck")
                 + " can be used to identify if there are any known CVE vulnerabilities in libraries utilized by an application. "
                 + Settings.getString("application.name", "DependencyCheck")
                 + " will automatically update required data from the Internet, such as the CVE and CPE data files from nvd.nist.gov." + nl + nl,
                 options,
                 "",
                 true);
     }
 
     /**
      * Retrieves the file command line parameter(s) specified for the 'scan'
      * argument.
      *
      * @return the file paths specified on the command line for scan
      */
     public String[] getScanFiles() {
         return line.getOptionValues(ArgumentName.SCAN);
     }
 
     /**
      * Returns the directory to write the reports to specified on the command
      * line.
      *
      * @return the path to the reports directory.
      */
     public String getReportDirectory() {
         return line.getOptionValue(ArgumentName.OUT, ".");
     }
 
     /**
      * Returns the output format specified on the command line. Defaults to HTML
      * if no format was specified.
      *
      * @return the output format name.
      */
     public String getReportFormat() {
         return line.getOptionValue(ArgumentName.OUTPUT_FORMAT, "HTML");
     }
 
     /**
      * Returns the application name specified on the command line.
      *
      * @return the application name.
      */
     public String getApplicationName() {
         return line.getOptionValue(ArgumentName.APP_NAME);
     }
 
     /**
      * Returns the connection timeout.
      *
      * @return the connection timeout
      */
     public String getConnectionTimeout() {
         return line.getOptionValue(ArgumentName.CONNECTION_TIMEOUT);
     }
 
     /**
      * Returns the proxy url.
      *
      * @return the proxy url
      */
     public String getProxyUrl() {
         return line.getOptionValue(ArgumentName.PROXY_URL);
     }
 
     /**
      * Returns the proxy port.
      *
      * @return the proxy port
      */
     public String getProxyPort() {
         return line.getOptionValue(ArgumentName.PROXY_PORT);
     }
 
     /**
      * Get the value of dataDirectory.
      *
      * @return the value of dataDirectory
      */
     public String getDataDirectory() {
         return line.getOptionValue(ArgumentName.DATA_DIRECTORY);
     }
 
     /**
      * <p>Prints the manifest information to standard output.</p>
      * <ul><li>Implementation-Title: ${pom.name}</li>
      * <li>Implementation-Version: ${pom.version}</li></ul>
      */
     public void printVersionInfo() {
         final String version = String.format("%s version %s",
                 Settings.getString("application.name", "DependencyCheck"),
                 Settings.getString("application.version", "Unknown"));
         System.out.println(version);
     }
 
     /**
      * Checks if the auto update feature has been disabled. If it has been
      * disabled via the command line this will return false.
      *
      * @return if auto-update is allowed.
      */
     public boolean isAutoUpdate() {
         return (line == null) || !line.hasOption(ArgumentName.DISABLE_AUTO_UPDATE);
     }
 
     /**
      * A collection of static final strings that represent the possible command
      * line arguments.
      */
     public static class ArgumentName {
 
         /**
          * The long CLI argument name specifying the directory/file to scan.
          */
         public static final String SCAN = "scan";
         /**
          * The short CLI argument name specifying the directory/file to scan.
          */
         public static final String SCAN_SHORT = "s";
         /**
          * The long CLI argument name specifying that the CPE/CVE/etc. data
          * should not be automatically updated.
          */
         public static final String DISABLE_AUTO_UPDATE = "noupdate";
         /**
          * The short CLI argument name specifying that the CPE/CVE/etc. data
          * should not be automatically updated.
          */
         public static final String DISABLE_AUTO_UPDATE_SHORT = "n";
         /**
          * The long CLI argument name specifying the directory to write the
          * reports to.
          */
         public static final String OUT = "out";
         /**
          * The short CLI argument name specifying the directory to write the
          * reports to.
          */
         public static final String OUT_SHORT = "o";
         /**
          * The long CLI argument name specifying the output format to write the
          * reports to.
          */
         public static final String OUTPUT_FORMAT = "format";
         /**
          * The short CLI argument name specifying the output format to write the
          * reports to.
          */
         public static final String OUTPUT_FORMAT_SHORT = "f";
         /**
          * The long CLI argument name specifying the name of the application to
          * be scanned.
          */
         public static final String APP_NAME = "app";
         /**
          * The short CLI argument name specifying the name of the application to
          * be scanned.
          */
         public static final String APP_NAME_SHORT = "a";
         /**
          * The long CLI argument name asking for help.
          */
         public static final String HELP = "help";
         /**
          * The short CLI argument name asking for help.
          */
         public static final String HELP_SHORT = "h";
         /**
          * The long CLI argument name asking for the version.
          */
         public static final String VERSION_SHORT = "v";
         /**
          * The short CLI argument name asking for the version.
          */
         public static final String VERSION = "version";
         /**
          * The short CLI argument name indicating the proxy port.
          */
         public static final String PROXY_PORT_SHORT = "p";
         /**
          * The CLI argument name indicating the proxy port.
          */
         public static final String PROXY_PORT = "proxyport";
         /**
          * The short CLI argument name indicating the proxy url.
          */
         public static final String PROXY_URL_SHORT = "u";
         /**
          * The CLI argument name indicating the proxy url.
          */
         public static final String PROXY_URL = "proxyurl";
         /**
          * The short CLI argument name indicating the proxy url.
          */
         public static final String CONNECTION_TIMEOUT_SHORT = "c";
         /**
          * The CLI argument name indicating the proxy url.
          */
         public static final String CONNECTION_TIMEOUT = "connectiontimeout";
         /**
          * The short CLI argument name for setting the location of an additional
          * properties file.
          */
         public static final String PROP_SHORT = "p";
         /**
          * The CLI argument name for setting the location of an additional
          * properties file.
          */
         public static final String PROP = "propertyfile";
         /**
          * The CLI argument name for setting the location of the data directory.
          */
         public static final String DATA_DIRECTORY = "data";
         /**
          * The short CLI argument name for setting the location of the data
          * directory.
          */
         public static final String DATA_DIRECTORY_SHORT = "d";
     }
 }