/*
    * This file is part of ***  M y C o R e  ***
    * See http://www.mycore.de/ for details.
    *
    * MyCoRe is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    *
   * MyCoRe is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with MyCoRe.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.mycore.datamodel.metadata;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.stream.Collectors;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.jdom2.Content;
  import org.jdom2.Element;
  import org.mycore.common.MCRException;
  import org.mycore.common.xml.MCRXMLHelper;
  
  import com.google.gson.JsonArray;
  import com.google.gson.JsonElement;
  import com.google.gson.JsonObject;
  
  /**
   * This class implements all method for handling with the MCRMetaLangText part
   * of a metadata object. The MCRMetaLangText class present a single item, which
   * has triples of a text and his corresponding language and optional a type.
   * 
   * @author Thomas Scheffler (yagee)
   * @author Jens Kupferschmidt
   * @author Johannes B\u00fchler
   * @version $Revision$ $Date$
   */
  public class MCRMetaXML extends MCRMetaDefault {
      List<Content> content;
  
      private static final Logger LOGGER = LogManager.getLogger();
  
      /**
       * This is the constructor. <br>
       * Set the java.util.ArrayList of child elements to new.
       */
      public MCRMetaXML() {
          super();
      }
  
      public MCRMetaXML(String subtag, String type, int inherited) throws MCRException {
          super(subtag, null, type, inherited);
      }
  
      /**
       * This method read the XML input stream part from a DOM part for the
       * metadata of the document.
       * 
       * @param element
       *            a relevant JDOM element for the metadata
       */
      @Override
      public void setFromDOM(Element element) {
          super.setFromDOM(element);
          content = element.cloneContent();
      }
  
      public void addContent(Content content) {
          if (this.content == null) {
              this.content = new ArrayList<>();
          }
  
          this.content.add(content);
      }
  
      public List<Content> getContent() {
          return content;
      }
  
      /**
       * This method create a XML stream for all data in this class, defined by
       * the MyCoRe XML MCRMetaLangText definition for the given subtag.
       * 
       * @exception MCRException
       *                if the content of this class is not valid
       * @return a JDOM Element with the XML MCRMetaLangText part
       */
      @Override
      public Element createXML() throws MCRException {
          Element elm = super.createXML();
          List<Content> addedContent = new ArrayList<>(content.size());
         cloneListContent(addedContent, content);
         elm.addContent(addedContent);
 
         return elm;
     }
 
     /**
      * Creates the JSON representation. Extends the {@link MCRMetaDefault#createJSON()} method
      * with the following data.
      * 
      * <pre>
      *   {
      *     content: [
      *       ... json objects of parsed content ...
      *     ]
      *   }
      * </pre>
      * 
      * @see MCRXMLHelper#jsonSerialize(Element)
      */
     @Override
     public JsonObject createJSON() {
         JsonObject json = super.createJSON();
         JsonArray jsonContentArray = new JsonArray();
         getContent().forEach(content -> {
             JsonElement jsonContent = MCRXMLHelper.jsonSerialize(content);
             if (jsonContent == null) {
                 LOGGER.warn("Unable to serialize xml content '{}' to json.", content);
                 return;
             }
             jsonContentArray.add(jsonContent);
         });
         json.add("content", jsonContentArray);
         return json;
     }
 
     private static void cloneListContent(List<Content> dest, List<Content> source) {
         dest.clear();
         for (Content c : source) {
             dest.add(c.clone());
         }
     }
 
     /**
      * Validates this MCRMetaXML. This method throws an exception if:
      * <ul>
      * <li>the subtag is not null or empty</li>
      * <li>the lang value was supported</li>
      * <li>the inherited value is lower than zero</li>
      * <li>the content is null</li>
      * </ul>
      * 
      * @throws MCRException the MCRMetaXML is invalid
      */
     public void validate() throws MCRException {
         super.validate();
         if (content == null) {
             throw new MCRException(getSubTag() + ": content is null or empty");
         }
     }
 
     /**
      * This method make a clone of this class.
      */
     @Override
     public MCRMetaXML clone() {
         MCRMetaXML clone = (MCRMetaXML) super.clone();
 
         clone.content = this.content.stream().map(Content::clone).collect(Collectors.toList());
 
         return clone;
     }
 
     /**
      * This method put debug data to the logger (for the debug mode).
      */
     @Override
     public void debug() {
         if (LOGGER.isDebugEnabled()) {
             super.debugDefault();
             LOGGER.debug("Number of contents  = \n{}", content.size());
         }
     }
 
     @Override
     public boolean equals(Object obj) {
         if (!super.equals(obj)) {
             return false;
         }
         final MCRMetaXML other = (MCRMetaXML) obj;
         return MCRXMLHelper.deepEqual(this.createXML(), other.createXML());
     }
 
 }