package com.atlassian.plugins.rest.doclet.generators.resourcedoc;
   
   import com.sun.jersey.api.model.AbstractResource;
   import com.sun.jersey.server.wadl.WadlGenerator;
   import com.sun.jersey.server.wadl.generators.resourcedoc.WadlGeneratorResourceDocSupport;
   import com.sun.jersey.server.wadl.generators.resourcedoc.model.ResourceDocType;
   import com.sun.research.ws.wadl.Resource;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
  import org.w3c.dom.Document;
  import org.w3c.dom.NamedNodeMap;
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  
  import java.net.URL;
  import java.util.HashMap;
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  
  /**
   * This class generates the WADL description of rest resources and considers the rest plugin module descriptors
   * configured inside the atlassian-plugin.xml file when generating the resource path.
   *
   * It builds up a map that contains a mapping of a package name to a resource path.
   * The full resource path is concatenated of the following strings:
   * 1) path as configured for rest plugin module descriptor: e.g. api
   * 2) version as configured for rest plugin module descriptor e.g. 2.0.alpha1
   * 3) path of the rest end point e.g. worklog
   * 
   * e.g. /api/2.0.alpha1/worklog/
   */
  public class AtlassianWadlGeneratorResourceDocSupport extends WadlGeneratorResourceDocSupport
  {
      private HashMap<String, ResourcePathInformation> resourcePathInformation;
  
      private static final Logger LOG = LoggerFactory.getLogger(AtlassianWadlGeneratorResourceDocSupport.class);
      private static final String ATLASSIAN_PLUGIN_XML = "atlassian-plugin.xml";
  
      public AtlassianWadlGeneratorResourceDocSupport()
      {
          super();
      }
  
      public AtlassianWadlGeneratorResourceDocSupport(WadlGenerator wadlGenerator, ResourceDocType resourceDoc)
      {
          super(wadlGenerator, resourceDoc);
      }
  
      @Override
      public void init() throws Exception
      {
          super.init();
          parseAtlassianPluginXML();
      }
  
      private void parseAtlassianPluginXML()
      {
          //get the factory
          DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
  
          try
          {
              final URL resource = getClass().getClassLoader().getResource(ATLASSIAN_PLUGIN_XML);
              if (resource == null) return;
              LOG.info("Found " + ATLASSIAN_PLUGIN_XML + " file! Looking for rest plugin module descriptors...");
  
              DocumentBuilder db = dbf.newDocumentBuilder();
  
              resourcePathInformation = new HashMap<String, ResourcePathInformation>();
  
              final Document document = db.parse(resource.toExternalForm());
              final NodeList restPluginModuleDescriptors = document.getElementsByTagName("rest");
              final int numPluginModuleDescriptors = restPluginModuleDescriptors.getLength();
              LOG.info("Found " + numPluginModuleDescriptors + " rest plugin module descriptors.");
  
              for (int i = 0; i < numPluginModuleDescriptors; i++)
              {
                  final Node node = restPluginModuleDescriptors.item(i);
  
                  final NamedNodeMap attributes = node.getAttributes();
                  final Node pathItem = attributes.getNamedItem("path");
                  final Node versionItem = attributes.getNamedItem("version");
                  if (pathItem == null || versionItem == null)
                      continue;
  
                  String resourcePath = pathItem.getNodeValue();
                  String version = versionItem.getNodeValue();
  
                  LOG.info("Found rest end point with path '" + resourcePath + "' and version '" + version + "'");
  
                  //Remove leading slash
                  if (resourcePath.indexOf("/") != -1)
                  {
                      resourcePath = resourcePath.substring(resourcePath.indexOf("/") + 1);
                  }
  
                  final NodeList list = node.getChildNodes();
                  for (int j = 0; j < list.getLength(); j++)
                  {
                     final Node child = list.item(j);
                     if (child.getNodeName().equals("package"))
                     {
                         final String packageName = child.getFirstChild().getNodeValue();
                         LOG.info("Map package '" + packageName + "' to resource path '" + resourcePath + "' and version '" + version + "'");
                         resourcePathInformation.put(packageName, new ResourcePathInformation(resourcePath, version));
                     }
                 }
             }
         }
         catch (Exception ex)
         {
             LOG.error("Failed to read " + ATLASSIAN_PLUGIN_XML + " and parse rest plugin module descriptor information. Reason", ex);
         }
     }
 
     @Override
     public Resource createResource(AbstractResource r, String path)
     {
         final Resource result = super.createResource(r, path);
         boolean resourcePathChanged = false;
         for (String packageName : resourcePathInformation.keySet())
         {
             if (r.getResourceClass().getPackage().getName().startsWith(packageName))
             {
                 final ResourcePathInformation pathInformation = resourcePathInformation.get(packageName);
                 final String newPath = pathInformation.getPath() + "/" + pathInformation.getVersion() + "/" + result.getPath();
                 result.setPath(newPath);
                 resourcePathChanged = true;
                 LOG.info("Setting resource path of rest end point '" + r.getResourceClass().getCanonicalName() + "' to '" + newPath + "'");
                 break;
             }
         }
         if (!resourcePathChanged)
         {
             LOG.info("Resource path of rest end point '" + r.getResourceClass().getCanonicalName() + "' unchanged no mapping to rest plugin module descriptor found.");
         }
 
         return result;
     }
 
     public class ResourcePathInformation
     {
         private final String path;
         private final String version;
 
         public ResourcePathInformation(String path, String version)
         {
             this.path = path;
             this.version = version;
         }
 
         public String getVersion()
         {
             return version;
         }
 
         public String getPath()
         {
             return path;
         }
     }
 
 }