/*
    * Copyright (C) 2003-2010 eXo Platform SAS.
    *
    * This program is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Affero General Public License
    * as published by the Free Software Foundation; either version 3
    * of the License, or (at your option) any later version.
    *
    * This program 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 this program; if not, see<http://www.gnu.org/licenses/>.
   */
  package org.exoplatform.wiki.service.wysiwyg;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import org.apache.commons.lang.StringUtils;
  import org.exoplatform.services.log.ExoLogger;
  import org.exoplatform.services.log.Log;
  import org.xwiki.gwt.wysiwyg.client.wiki.WikiPageReference;
  import org.xwiki.model.EntityType;
  import org.xwiki.model.reference.AttachmentReference;
  import org.xwiki.model.reference.DocumentReference;
  import org.xwiki.model.reference.EntityReference;
  
  public class EntityReferenceConverter {
    /**
     * Maps entity types to client reference component names.
     */
    private static final Map<EntityType, String> REFERENCE_COMPONENT_NAME;
    
    private static final Log      log               = ExoLogger.getLogger(EntityReferenceConverter.class);
  
    static {
      REFERENCE_COMPONENT_NAME = new HashMap<EntityType, String>();
      REFERENCE_COMPONENT_NAME.put(org.xwiki.model.EntityType.WIKI, WikiPageReference.WIKI_NAME);
      REFERENCE_COMPONENT_NAME.put(EntityType.SPACE, WikiPageReference.SPACE_NAME);
      REFERENCE_COMPONENT_NAME.put(EntityType.DOCUMENT, WikiPageReference.PAGE_NAME);
      REFERENCE_COMPONENT_NAME.put(EntityType.ATTACHMENT,
                                   org.xwiki.gwt.wysiwyg.client.wiki.AttachmentReference.FILE_NAME);
    }
  
    /**
     * Converts an entity reference received from the client to an entity
     * reference to be used on the server.
     * 
     * @param clientEntityReference a client-side entity reference
     * @return a server-side entity reference
     */
    public EntityReference convert(org.xwiki.gwt.wysiwyg.client.wiki.EntityReference clientEntityReference) {
      if (clientEntityReference == null) {
        return null;
      }
      EntityReference serverEntityReference = null;
      String wikiName = clientEntityReference.getComponent(REFERENCE_COMPONENT_NAME.get(EntityType.WIKI));
      if (!StringUtils.isEmpty(wikiName)) {
        serverEntityReference = new EntityReference(wikiName, EntityType.WIKI);
      }
      String spaceName = clientEntityReference.getComponent(REFERENCE_COMPONENT_NAME.get(EntityType.SPACE));
      if (!StringUtils.isEmpty(spaceName)) {
        serverEntityReference = new EntityReference(spaceName,
                                                    EntityType.SPACE,
                                                    serverEntityReference);
      }
      String pageName = clientEntityReference.getComponent(REFERENCE_COMPONENT_NAME.get(EntityType.DOCUMENT));
      if (!StringUtils.isEmpty(pageName)) {
        serverEntityReference = new EntityReference(pageName,
                                                    EntityType.DOCUMENT,
                                                    serverEntityReference);
      }
      String fileName = clientEntityReference.getComponent(REFERENCE_COMPONENT_NAME.get(EntityType.ATTACHMENT));
      if (!StringUtils.isEmpty(fileName)) {
        serverEntityReference = new EntityReference(fileName,
                                                    EntityType.ATTACHMENT,
                                                    serverEntityReference);
      }
      return serverEntityReference;
    }
  
    /**
     * Converts an entity reference used on the server side to an entity reference
     * to be sent to the client.
     * 
     * @param serverEntityReference a server-side entity reference
     * @return the corresponding client-side entity reference
     */
    public org.xwiki.gwt.wysiwyg.client.wiki.EntityReference convert(EntityReference serverEntityReference) {
      org.xwiki.gwt.wysiwyg.client.wiki.EntityReference clientEntityReference = new org.xwiki.gwt.wysiwyg.client.wiki.EntityReference();
      try {
        clientEntityReference.setType(org.xwiki.gwt.wysiwyg.client.wiki.EntityReference.EntityType.valueOf(serverEntityReference.getType()
                                                                                                                                .toString()));
      } catch (Exception e) {
        log.error("Can't set type for client entity reference", e);
        return null;
     }
     EntityReference child = serverEntityReference;
     while (child != null) {
       String componentName = REFERENCE_COMPONENT_NAME.get(child.getType());
       if (componentName != null) {
         clientEntityReference.setComponent(componentName, child.getName());
       }
       child = child.getParent();
     }
     return clientEntityReference;
   }
 
   /**
    * @param documentReference a document reference
    * @return the corresponding wiki page reference
    */
   public WikiPageReference convert(DocumentReference documentReference) {
     String wikiName = documentReference.getWikiReference().getName();
     String spaceName = documentReference.getLastSpaceReference().getName();
     String pageName = documentReference.getName();
     return new WikiPageReference(wikiName, spaceName, pageName);
   }
 
   /**
    * @param reference a wiki page reference
    * @return the corresponding document reference
    */
   public DocumentReference convert(WikiPageReference reference) {
     return new DocumentReference(reference.getWikiName(),
                                  reference.getSpaceName(),
                                  reference.getPageName());
   }
 
   /**
    * @param attachmentReference an attachment reference
    * @return the corresponding client attachment reference
    */
   public org.xwiki.gwt.wysiwyg.client.wiki.AttachmentReference convert(org.xwiki.model.reference.AttachmentReference attachmentReference) {
     return new org.xwiki.gwt.wysiwyg.client.wiki.AttachmentReference(attachmentReference.getName(),
                                                                      convert(attachmentReference.getDocumentReference()));
   }
 
   /**
    * @param clientAttachmentReference a client attachment reference
    * @return the corresponding server-side attachment reference
    */
   public AttachmentReference convert(org.xwiki.gwt.wysiwyg.client.wiki.AttachmentReference clientAttachmentReference) {
     return new AttachmentReference(clientAttachmentReference.getFileName(),
                                    convert(clientAttachmentReference.getWikiPageReference()));
   }
 }