/**
    *
    * Copyright 2004 The Apache Software Foundation
    *
    * 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.
   */
  package org.codehaus.plexus.archiver.jar;
  
  import java.io.IOException;
  import java.util.Map;
  import java.util.Properties;
  import java.util.jar.Attributes;
  
  import org.codehaus.plexus.archiver.ArchiverException;
  import org.codehaus.plexus.util.PropertyUtils;
  
  /**
   * Not part of any public API
   *
   * @author Kristian Rosenvold
   */
  class JdkManifestFactory {
  
      public static java.util.jar.Manifest getDefaultManifest() throws ArchiverException {
          final java.util.jar.Manifest defaultManifest = new java.util.jar.Manifest();
          defaultManifest.getMainAttributes().putValue("Manifest-Version", "1.0");
  
          String createdBy = "Plexus Archiver";
  
          final String plexusArchiverVersion = getArchiverVersion();
  
          if (plexusArchiverVersion != null) {
              createdBy += " " + plexusArchiverVersion;
          }
  
          defaultManifest.getMainAttributes().putValue("Created-By", createdBy);
          return defaultManifest;
      }
  
      static String getArchiverVersion() {
          try {
              final Properties properties = PropertyUtils.loadProperties(JdkManifestFactory.class.getResourceAsStream(
                      "/META-INF/maven/org.codehaus.plexus/plexus-archiver/pom.properties"));
  
              return properties != null ? properties.getProperty("version") : null;
  
          } catch (final IOException e) {
              throw new AssertionError(e);
          }
      }
  
      public static void merge(java.util.jar.Manifest target, java.util.jar.Manifest other, boolean overwriteMain) {
          if (other != null) {
              final Attributes mainAttributes = target.getMainAttributes();
              if (overwriteMain) {
                  mainAttributes.clear();
                  mainAttributes.putAll(other.getMainAttributes());
              } else {
                  mergeAttributes(mainAttributes, other.getMainAttributes());
              }
  
              for (Map.Entry<String, Attributes> o : other.getEntries().entrySet()) {
                  Attributes ourSection = target.getAttributes(o.getKey());
                  Attributes otherSection = o.getValue();
                  if (ourSection == null) {
                      if (otherSection != null) {
                          target.getEntries().put(o.getKey(), (Attributes) otherSection.clone());
                      }
                  } else {
                      mergeAttributes(ourSection, otherSection);
                  }
              }
          }
      }
  
      /**
       * Merge in another section
       *
       * @param target The target manifest of the merge
       * @param section the section to be merged with this one.
       */
      public static void mergeAttributes(java.util.jar.Attributes target, java.util.jar.Attributes section) {
          for (Object o : section.keySet()) {
              java.util.jar.Attributes.Name key = (Attributes.Name) o;
              final Object value = section.get(o);
              // the merge file always wins
              target.put(key, value);
          }
      }
 }