/*
    * 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.frontend.xeditor.target;
  
  import java.util.Map;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.jaxen.JaxenException;
  import org.jdom2.Document;
  import org.jdom2.Element;
  import org.jdom2.JDOMException;
  import org.mycore.frontend.servlets.MCRServletJob;
  import org.mycore.frontend.xeditor.MCRBinding;
  import org.mycore.frontend.xeditor.MCREditorSession;
  import org.mycore.frontend.xeditor.tracker.MCRChangeData;
  
  import jakarta.servlet.ServletContext;
  
  public class MCRSubselectReturnTarget implements MCREditorTarget {
  
      private static final Logger LOGGER = LogManager.getLogger(MCRSubselectReturnTarget.class);
  
      @Override
      public void handleSubmission(ServletContext context, MCRServletJob job, MCREditorSession session, String parameter)
          throws Exception {
          String baseXPath = getBaseXPathForSubselect(session);
          LOGGER.info("Returning from subselect for {}", baseXPath);
  
          if ("cancel".equals(parameter)) {
              session.setBreakpoint("After canceling subselect for " + baseXPath);
          } else {
              Map<String, String[]> submittedValues = MCRTargetUtils.getSubmittedValues(job, baseXPath);
              session.getSubmission().setSubmittedValues(submittedValues);
              session.setBreakpoint("After returning from subselect for " + baseXPath);
          }
  
          job.getResponse().sendRedirect(job.getResponse().encodeRedirectURL(session.getRedirectURL(null)));
      }
  
      private String getBaseXPathForSubselect(MCREditorSession session) throws JaxenException, JDOMException {
          Document doc = session.getEditedXML();
          MCRChangeData change = session.getChangeTracker().findLastChange(doc);
          String text = change.getText();
          String xPath = text.substring(text.lastIndexOf(" ") + 1).trim();
          return bindsFirstOrMoreThanOneElement(xPath, session) ? xPath + "[1]" : xPath;
      }
  
      private boolean bindsFirstOrMoreThanOneElement(String xPath, MCREditorSession session)
          throws JaxenException, JDOMException {
          MCRBinding binding = new MCRBinding(xPath, false, session.getRootBinding());
          boolean result = (binding.getBoundNode() instanceof Element) && !xPath.endsWith("]");
          binding.detach();
          return result;
      }
  }