/**
    * Portions of this software was developed by employees of the National Institute
    * of Standards and Technology (NIST), an agency of the Federal Government and is
    * being made available as a public service. Pursuant to title 17 United States
    * Code Section 105, works of NIST employees are not subject to copyright
    * protection in the United States. This software may be subject to foreign
    * copyright. Permission in the United States and in foreign countries, to the
    * extent that NIST may hold copyright, to use, copy, modify, create derivative
    * works, and distribute this software and its documentation without fee is hereby
   * granted on a non-exclusive basis, provided that this notice and disclaimer
   * of warranty appears in all copies.
   *
   * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
   * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
   * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
   * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
   * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
   * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
   * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
   * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
   * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
   * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
   * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
   */
  
  package gov.nist.secauto.decima.xml.templating.document.post.template;
  
  import gov.nist.secauto.decima.core.document.DocumentException;
  import gov.nist.secauto.decima.core.document.handling.DocumentPostProcessor;
  import gov.nist.secauto.decima.core.document.handling.ResourceResolver;
  import gov.nist.secauto.decima.xml.document.MutableXMLDocument;
  import gov.nist.secauto.decima.xml.document.XMLDocument;
  
  import org.jdom2.Attribute;
  import org.jdom2.Document;
  import org.jdom2.Element;
  
  public class TemplatePostProcessor implements DocumentPostProcessor<MutableXMLDocument> {
    public static final String TEMPLATE_NAMESPACE_URI = "http://csrc.nist.gov/ns/decima/template/1.0";
    public static final String TEMPLATE_LOCAL_NAME = "template";
    public static final String TEMPLATE_XPATH;
    public static final String TEMPLATE_ATTRIBUTE = "template";
  
    static {
      StringBuilder builder = new StringBuilder();
      builder.append("/*[namespace-uri()='");
      builder.append(TEMPLATE_NAMESPACE_URI);
      builder.append("' and local-name() = '");
      builder.append(TEMPLATE_LOCAL_NAME);
      builder.append("']");
      TEMPLATE_XPATH = builder.toString();
    }
  
    public TemplatePostProcessor() {
      super();
    }
  
    @Override
    public boolean handles(MutableXMLDocument subject) throws DocumentException {
      Document document = subject.getJDOMDocument(false);
      boolean retval = false;
      if (document.hasRootElement()) {
        Element root = document.getRootElement();
        if (TEMPLATE_LOCAL_NAME.equals(root.getName()) && TEMPLATE_NAMESPACE_URI.equals(root.getNamespace().getURI())) {
          retval = true;
        }
      }
      return retval;
    }
  
    @Override
    public MutableXMLDocument process(MutableXMLDocument subject, ResourceResolver<MutableXMLDocument> resolver)
        throws DocumentException {
      Document document = subject.getJDOMDocument(false);
      Element root = document.getRootElement();
      Attribute attribute = root.getAttribute(TEMPLATE_ATTRIBUTE);
      if (attribute == null) {
        throw new DocumentException("The document's root element doesn't have an attribute named 'template'.");
      }
  
      TemplateProcessor tp = newTemplateProcessor(subject);
      return tp.generate(resolver);
    }
  
    protected TemplateProcessor newTemplateProcessor(XMLDocument document) throws DocumentException {
      TemplateProcessor retval;
      try {
        retval = TemplateParser.getInstance().parse(document);
      } catch (TemplateParserException e) {
        throw new DocumentException("Unable to parse template", e);
      }
      return retval;
    }
  
  }