/*
    * 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.
   */
  package org.apache.maven.scm.provider.git.util;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.maven.scm.providers.gitlib.settings.Settings;
  import org.apache.maven.scm.providers.gitlib.settings.io.xpp3.GitXpp3Reader;
  import org.codehaus.plexus.util.ReaderFactory;
  import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
  
  /**
   * @author <a href="mailto:evenisse@apache.org">Emmanuel Venisse</a>
   */
  public class GitUtil {
      protected static final String GIT_SETTINGS_FILENAME = "git-settings.xml";
  
      public static final File DEFAULT_SETTINGS_DIRECTORY = new File(System.getProperty("user.home"), ".scm");
  
      /** The password placeholder must contain delimiters.
       *  Otherwise replacing may replace other portions of the URL as well
       *  and in worst case passwords could be guessed. */
      public static final String PASSWORD_PLACE_HOLDER_WITH_DELIMITERS = ":********@";
  
      private static final Pattern PASSWORD_IN_URL_PATTERN = Pattern.compile("^.*(:[^/].*@).*$");
  
      private static File settingsDirectory = DEFAULT_SETTINGS_DIRECTORY;
  
      private static Settings settings;
  
      private GitUtil() {
          // no op
      }
  
      public static Settings getSettings() {
          if (settings == null) {
              settings = readSettings();
          }
          return settings;
      }
  
      public static Settings readSettings() {
          File settingsFile = getSettingsFile();
  
          if (settingsFile.exists()) {
              GitXpp3Reader reader = new GitXpp3Reader();
              try {
                  return reader.read(ReaderFactory.newXmlReader(settingsFile));
              } catch (IOException e) {
                  // Nothing to do
              } catch (XmlPullParserException e) {
                  String message = settingsFile.getAbsolutePath() + " isn't well formed. SKIPPED." + e.getMessage();
  
                  System.err.println(message);
              }
          }
  
          return new Settings();
      }
  
      public static void setSettingsDirectory(File directory) {
          settingsDirectory = directory;
          settings = readSettings();
      }
  
      public static File getSettingsFile() {
          return new File(settingsDirectory, GIT_SETTINGS_FILENAME);
      }
  
      /**
       * Provides an anonymous output to mask password. Considering URL of type :
       * &lt;&lt;protocol&gt;&gt;://&lt;&lt;user&gt;&gt;:&lt;&lt;password&gt;&gt;@
       * &lt;&lt;host_definition&gt;&gt;
       *
       * @param urlWithCredentials
       * @return urlWithCredentials but password masked with stars
       */
      public static String maskPasswordInUrl(String urlWithCredentials) {
          String output = urlWithCredentials;
         final Matcher passwordMatcher = PASSWORD_IN_URL_PATTERN.matcher(output);
         if (passwordMatcher.find()) {
             // clear password with delimiters
             final String clearPasswordWithDelimiters = passwordMatcher.group(1);
             // to be replaced in output by stars with delimiters
             output = StringUtils.replace(output, clearPasswordWithDelimiters, PASSWORD_PLACE_HOLDER_WITH_DELIMITERS);
         }
         return output;
     }
 }