/*
    * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH
    *
    * 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 de.smartics.properties.reports;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.util.List;
  
  import javax.annotation.concurrent.NotThreadSafe;
  
  import org.apache.commons.lang.StringUtils;
  import org.jdom.Document;
  import org.jdom.Element;
  import org.jdom.Namespace;
  import org.jdom.output.XMLOutputter;
  
  import de.smartics.properties.api.core.domain.DocumentMetaData;
  
  /**
   * Base implementation for reporter. A reporter is a helper to render commonly
   * (i.e. by {@link XmlPropertyReporter} and {@link PropertySet Reporter}) used meta
   * data. The report concept is not part of the public API.
   */
  @NotThreadSafe
  abstract class AbstractReporter
  { // NOPMD
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    /**
     * The XHTML namespace.
     */
    protected static final String XHTML = "http://www.w3.org/1999/xhtml";
  
    // --- members --------------------------------------------------------------
  
    /**
     * The namespace of the document that is created.
     */
    protected final Namespace ns;
  
    /**
     * The XHTML namespace.
     */
    protected final Namespace nsXhtml;
  
    /**
     * The root element of the created document.
     */
    protected Element rootElement;
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    protected AbstractReporter(final String namespace)
    {
      ns = Namespace.getNamespace(namespace);
      nsXhtml = Namespace.getNamespace(XHTML);
    }
  
    // ****************************** Inner Classes *****************************
  
    // ********************************* Methods ********************************
  
    // --- init -----------------------------------------------------------------
  
    // --- get&set --------------------------------------------------------------
  
    // --- business -------------------------------------------------------------
  
    protected final Document buildDocument(final String rootGi)
    {
      final String name = getName();
      rootElement = new Element(rootGi, ns);
      rootElement.setAttribute("name", name);
  
      writeMetaData();
  
      final Document document = new Document(rootElement);
      return document;
    }
  
    /**
     * Returns the unique identifier of the report to be created.
    *
    * @return the unique identifier of the report to be created.
    */
   protected abstract String getName();
 
   protected abstract String getSpace();
 
   protected abstract String getTitle();
 
   protected abstract DocumentMetaData getMetaData();
 
   protected abstract String getComment();
 
   private void writeMetaData()
   {
     writeIdentification();
     writeFiling();
     writeDescription();
   }
 
   private void writeIdentification()
   {
     final Element identificationElement = new Element("identification", ns);
 
     final String space = getSpace();
     addElement(identificationElement, "space", space);
 
     final String title = getTitle();
     addElement(identificationElement, "title", title);
 
     if (!identificationElement.getChildren().isEmpty())
     {
       rootElement.addContent(identificationElement);
     }
   }
 
   private void writeFiling()
   {
     final DocumentMetaData metadata = getMetaData();
     final Element filingElement = new Element("filing", ns);
 
     final List<String> parents = metadata.getParents();
     addItems(parents, filingElement, "parents", "parent");
 
     final List<String> categories = metadata.getCategories();
     addItems(categories, filingElement, "categories", "category");
 
     final List<String> tags = metadata.getTags();
     addItems(tags, filingElement, "tags", "tag");
 
     final String sortKey = metadata.getSortKey();
     addElement(filingElement, "sortKey", sortKey);
 
     if (!filingElement.getChildren().isEmpty())
     {
       rootElement.addContent(filingElement);
     }
   }
 
   protected final void addItems(final List<String> items,
       final Element rootElement, final String itemsGi, final String itemGi)
   {
     if (!items.isEmpty())
     {
       final Element containerElement = new Element(itemsGi, ns);
       for (final String item : items)
       {
         final Element itemElement = new Element(itemGi, ns);
         itemElement.setText(item);
         containerElement.addContent(itemElement);
       }
       rootElement.addContent(containerElement);
     }
   }
 
   protected final void writeDescription()
   {
     final DocumentMetaData metadata = getMetaData();
     final Element descriptionElement = new Element("description", ns);
 
     final List<String> categories = metadata.getAudience();
     addItems(categories, descriptionElement, "audience", "member");
 
     final String shortDescription = metadata.getShortDescription();
     addDescElement(descriptionElement, "shortDescription", shortDescription);
 
     final String summary = metadata.getSummary();
     addDescElement(descriptionElement, "summary", summary);
 
     final List<String> notes = metadata.getNotes();
     if (!notes.isEmpty())
     {
       final Element notesElement = new Element("notes", ns);
       final Element ol = new Element("ol", nsXhtml);
       for (final String note : notes)
       {
         final Element li = new Element("li", nsXhtml);
         li.setText(note);
         ol.addContent(li);
       }
       notesElement.addContent(ol);
 
       descriptionElement.addContent(notesElement);
     }
 
     // no authors provided currently
 
     if (!descriptionElement.getChildren().isEmpty())
     {
       rootElement.addContent(descriptionElement);
     }
   }
 
   protected final void addElement(final Element rootElement, final String gi,
       final String content)
   {
     if (StringUtils.isNotBlank(content))
     {
       final Element element = new Element(gi, ns);
       element.setText(content);
       rootElement.addContent(element);
     }
   }
 
   protected final void addDescElement(final Element rootElement,
       final String gi, final String content)
   {
     if (StringUtils.isNotBlank(content))
     {
       final Element element = new Element(gi, ns);
       writeXmlSubStructure(element, content);
       rootElement.addContent(element);
     }
   }
 
   protected final void writeSpecification(final String comment)
   {
     final Element specification = new Element("specification", ns);
     writeXmlSubStructure(specification, comment);
     rootElement.addContent(specification);
   }
 
   protected final void writeXmlSubStructure(final Element element,
       final String xmlContent)
   {
     // FIXME: Handle XML properly
     element.setText(xmlContent);
   }
 
   protected final void writeXml(final OutputStream out, final Document document)
     throws IOException
   {
     final XMLOutputter outp = new XMLOutputter();
     outp.output(document, out);
   }
 
   // --- object basics --------------------------------------------------------
 
 }