/*
    * 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.mods.access.facts.condition;
  
  import java.util.Optional;
  
  import org.jdom2.Element;
  import org.mycore.access.facts.MCRFactsHolder;
  import org.mycore.access.facts.condition.fact.MCRStringCondition;
  import org.mycore.access.facts.fact.MCRObjectIDFact;
  import org.mycore.access.facts.fact.MCRStringFact;
  import org.mycore.datamodel.metadata.MCRObject;
  import org.mycore.mods.MCRMODSEmbargoUtils;
  
  /**
   * condition for fact-based access system, that checks 
   * if an embargo exists for a given MyCoRe object 
   * 
   * @author Robert Stephan
   *
   */
  public class MCRMODSEmbargoCondition extends MCRStringCondition {
  
      private String idFact = "objid";
  
      @Override
      public void parse(Element xml) {
          super.parse(xml);
          this.idFact = Optional.ofNullable(xml.getAttributeValue("idfact")).orElse("objid");
      }
  
      @Override
      public Optional<MCRStringFact> computeFact(MCRFactsHolder facts) {
          Optional<MCRObjectIDFact> idc = facts.require(idFact);
          if (idc.isPresent()) {
              Optional<MCRObject> optMCRObject = idc.get().getObject();
              if (optMCRObject.isPresent()) {
                  String embargo = MCRMODSEmbargoUtils.getEmbargo(optMCRObject.get());
  
                  //only positive facts are added to the facts holder
                  if (embargo != null) {
                      MCRStringFact fact = new MCRStringFact(getFactName(), getTerm());
                      fact.setValue(embargo);
                      facts.add(fact);
                      return Optional.of(fact);
                  }
              }
          }
          return Optional.empty();
      }
  }