package com.atlassian.plugin.osgi.factory;
   
   import com.atlassian.plugin.Application;
   import com.atlassian.plugin.ModuleDescriptor;
   import com.atlassian.plugin.ModuleDescriptorFactory;
   import com.atlassian.plugin.Plugin;
   import com.atlassian.plugin.PluginParseException;
   import com.atlassian.plugin.parsers.XmlDescriptorParser;
   import org.dom4j.Element;
  
  import java.io.InputStream;
  import java.util.Set;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  /**
   * Descriptor parser that handles special tasks for osgi plugins such as recording the
   * originating module descriptor elements. Must only be used with {@link OsgiPlugin} instances.
   *
   * @since 2.1.2
   */
  public class OsgiPluginXmlDescriptorParser extends XmlDescriptorParser {
      /**
       * @param source       The XML descriptor source
       * @param applications The application keys to limit modules to, null for only unspecified
       * @throws com.atlassian.plugin.PluginParseException if there is a problem reading the descriptor from the XML {@link java.io.InputStream}.
       */
      public OsgiPluginXmlDescriptorParser(final InputStream source, final Set<Application> applications) throws PluginParseException {
          super(checkNotNull(source, "The descriptor source must not be null"), applications);
      }
  
      /**
       * Creates a DescriptorParser that can read multiple XML files
       *
       * @param source              The descriptor stream
       * @param supplementalSources streams that contain additional module descriptors
       * @param applications        the application key to filter modules with, null for all unspecified
       * @throws PluginParseException if there is a problem reading the descriptor from the XML {@link InputStream}.
       * @since 3.2.16
       */
      public OsgiPluginXmlDescriptorParser(final InputStream source, final Iterable<InputStream> supplementalSources,
                                           final Set<Application> applications) throws PluginParseException {
          super(source, supplementalSources, applications);
      }
  
  
      /**
       * Passes module descriptor elements back to the {@link OsgiPlugin}
       *
       * @param plugin                  The plugin
       * @param element                 The module element
       * @param moduleDescriptorFactory The module descriptor factory
       * @return The module, or null if the module cannot be found
       * @throws PluginParseException
       */
      @Override
      protected ModuleDescriptor<?> createModuleDescriptor(final Plugin plugin, final Element element,
                                                           final ModuleDescriptorFactory moduleDescriptorFactory) throws PluginParseException {
          final ModuleDescriptor<?> descriptor = super.createModuleDescriptor(plugin, element, moduleDescriptorFactory);
  
          passModuleDescriptorToPlugin(plugin, element, descriptor);
  
          return descriptor;
      }
  
      /**
       * Passes module descriptor elements back to the {@link OsgiPlugin}
       */
      @Override
      public ModuleDescriptor<?> addModule(final ModuleDescriptorFactory moduleDescriptorFactory, final Plugin plugin,
                                           final Element module) {
          final ModuleDescriptor<?> descriptor = super.addModule(moduleDescriptorFactory, plugin, module);
  
          passModuleDescriptorToPlugin(plugin, module, descriptor);
  
          return descriptor;
      }
  
      /**
       * Passes module descriptor elements back to the {@link OsgiPlugin}
       */
      private void passModuleDescriptorToPlugin(final Plugin plugin, final Element element, final ModuleDescriptor<?> descriptor) {
          if (plugin instanceof OsgiPlugin) {
              final String key;
              if (descriptor == null) {
                  key = element.attributeValue("key");
              } else {
                  key = descriptor.getKey();
              }
  
              ((OsgiPlugin) plugin).addModuleDescriptorElement(key, element);
          }
      }
  }