/*
    * Copyright (C) 2017-2019 Centre National d'Etudes Spatiales (CNES).
    *
    * This library is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Lesser General Public
    * License as published by the Free Software Foundation; either
    * version 3.0 of the License, or (at your option) any later version.
    *
    * This library 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   * MA 02110-1301  USA
   */
  package fr.cnes.doi.application;
  
  import fr.cnes.doi.client.ClientCrossCiteCitation;
  import fr.cnes.doi.resource.citation.FormatCitationResource;
  import fr.cnes.doi.resource.citation.LanguageCitationResource;
  import fr.cnes.doi.resource.citation.StyleCitationResource;
  import fr.cnes.doi.settings.Consts;
  import fr.cnes.doi.utils.spec.Requirement;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.ThreadContext;
  import org.restlet.Request;
  import org.restlet.Response;
  import org.restlet.Restlet;
  import org.restlet.data.ClientInfo;
  import org.restlet.routing.Filter;
  import org.restlet.routing.Router;
  
  /**
   * Provides an application to get citation from a registered DOI. Books and
   * journal articles have long benefited from an infrastructure that makes them
   * easy to cite, a key element in the process of research and academic
   * discourse. In this mind, a data should cited in just the same way. DataCite
   * DOIs help further research and assures reliable, predictable, and unambiguous
   * access to research data in order to:
   * <ul>
   * <li>support proper attribution and credit</li>
   * <li>support collaboration and reuse of data</li>
   * <li>enable reproducibility of findings</li>
   * <li>foster faster and more efficient research progress, and</li>
   * <li>provide the means to share data with future researchers</li>
   * </ul>
   * DataCite also looks to community practices that provide data citation
   * guidance. The Joint Declaration of Data Citation Principles is a set of
   * guiding principles for data within scholarly literature, another dataset, or
   * any other research object (Data Citation Synthesis Group 2014).
   * <p>
   * The FAIR Guiding Principles provide a guideline for the those that want to
   * enhance reuse of their data (Wilkinson 2016).
   * <p>
   * <b>Security</b><br>
   * --------------<br>
   * No authentication / no autorisation
   * <p>
   * <b>Routing</b><br>
   * --------------<br>
   * <br>
   * root<br>
   * |<br>
   * |__ style<br>
   * |__ language<br>
   * |__ format<br>
   *
   * @see <a href="http://citation.crosscite.org/">Making a citation</a>
   * @author Jean-Christophe Malapert (jean-christophe.malapert@cnes.fr)
   */
  @Requirement(reqId = Requirement.DOI_SRV_100, reqName = Requirement.DOI_SRV_100_NAME)
  @Requirement(reqId = Requirement.DOI_SRV_110, reqName = Requirement.DOI_SRV_110_NAME)
  @Requirement(reqId = Requirement.DOI_SRV_120, reqName = Requirement.DOI_SRV_120_NAME)
  @Requirement(reqId = Requirement.DOI_MONIT_020, reqName = Requirement.DOI_MONIT_020_NAME)
  public final class DoiCrossCiteApplication extends AbstractApplication {
  
      /**
       * URI {@value #STYLES_URI} to get the styles, which are used to format the
       * citation.
       */
      public static final String STYLES_URI = "/style";
      /**
       * URI {@value #LANGUAGE_URI} to get the languages, which are used to format
       * the citation.
       */
      public static final String LANGUAGE_URI = "/language";
      /**
       * URI {@value #FORMAT_URI} to retrieves the citation.
       */
      public static final String FORMAT_URI = "/format";
      /**
       * Application name.
       */
      public static final String NAME = "Cross Cite Application";
  
     /**
      * Logger.
      */
     private static final Logger LOG = LogManager.getLogger(DoiCrossCiteApplication.class.getName());
 
     /**
      * Client to query CrossCite.
      */
     private final ClientCrossCiteCitation client;
 
     /**
      * Constructs the application.
      */
     public DoiCrossCiteApplication() {
         super();
         setName(NAME);
         final StringBuilder description = new StringBuilder();
         description.append("Books and journal articles have long benefited from "
                 + "an infrastructure that makes them easy to cite, a key element"
                 + " in the process of research and academic discourse. "
                 + "We believe that you should cite data in just the same way "
                 + "that you can cite other sources of information, "
                 + "such as articles and books.");
         description.append("DataCite DOIs help further research and assures "
                 + "reliable, predictable, and unambiguous access to research "
                 + "data in order to:");
         description.append("<ul>");
         description.append("<li>support proper attribution and credit</li>");
         description.append("<li>support collaboration and reuse of data</li>");
         description.append("<li>enable reproducibility of findings</li>");
         description.append("<li>foster faster and more efficient research progress, and</li>");
         description.append("<li>provide the means to share data with future researchers</li>");
         description.append("</ul>");
         description.append("DataCite also looks to community practices that provide"
                 + " data citation guidance. The Joint Declaration of Data Citation"
                 + " Principles is a set of guiding principles for data within "
                 + "scholarly literature, another dataset, or any other research "
                 + "object (Data Citation Synthesis Group 2014). The FAIR Guiding "
                 + "Principles provide a guideline for the those that want to "
                 + "enhance reuse of their data (Wilkinson 2016).");
         setDescription(description.toString());
         final String contextMode = this.getConfig().getString(Consts.CONTEXT_MODE);
         this.client = new ClientCrossCiteCitation(
                 ClientCrossCiteCitation.Context.valueOf(contextMode)
         );
     }
 
     /**
      * Creates router the DOICrossCiteApplication. This routes routes the
      * following resources:
      * <ul>
      * <li>{@link DoiCrossCiteApplication#STYLES_URI} to access to the different
      * styles for a citation</li>
      * <li>{@link DoiCrossCiteApplication#LANGUAGE_URI} to access to the
      * different languages for a citation</li>
      * <li>{@link DoiCrossCiteApplication#FORMAT_URI} to access to the formatted
      * citation</li>
      * </ul>
      *
      * @return router
      */
     @Override
     public Restlet createInboundRoot() {
         LOG.traceEntry();
 
         final Filter logContext = new Filter() {
             /**
              * Get the IP client from proxy (if there is one) and set it in
              * the header.
              * 
              * @param request request
              * @param response response
              * @return 0
              */            
             @Override            
             protected int beforeHandle(final Request request, final Response response) {
                 final ClientInfo clientInfo = request.getClientInfo();
                 final String ipAddress = request.getHeaders().getFirstValue(
                         Consts.PROXIFIED_IP, clientInfo.getUpstreamAddress()
                 );
                 ThreadContext.put(Consts.LOG_IP_ADDRESS, ipAddress);
                 return Filter.CONTINUE;
             }
         };          
         
         final Router router = new Router(getContext());
         router.attach(STYLES_URI, StyleCitationResource.class);
         router.attach(LANGUAGE_URI, LanguageCitationResource.class);
         router.attach(FORMAT_URI, FormatCitationResource.class);
         
         logContext.setNext(router);
 
         return LOG.traceExit(logContext);
     }
 
     /**
      * Returns the client to query cross cite.
      *
      * @return the client
      */
     public ClientCrossCiteCitation getClient() {
         return this.client;
     }
 
     /**
      * Returns the logger.
      *
      * @return the logger
      */
     @Override
     public Logger getLog() {
         return LOG;
     }
 
 }