/*
    * Copyright (C) 2017 B3Partners B.V.
    *
    * 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 Affero General Public License for more details.
   *
   * You should have received a copy of the GNU Affero General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package nl.b3p.brmo.loader.xml;
  
  import java.io.InputStream;
  import java.io.StringWriter;
  import java.util.Date;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Map.Entry;
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  import javax.xml.parsers.ParserConfigurationException;
  import javax.xml.transform.OutputKeys;
  import javax.xml.transform.Source;
  import javax.xml.transform.Templates;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerFactory;
  import javax.xml.transform.dom.DOMSource;
  import javax.xml.transform.stream.StreamResult;
  import javax.xml.transform.stream.StreamSource;
  import javax.xml.xpath.XPath;
  import javax.xml.xpath.XPathConstants;
  import javax.xml.xpath.XPathExpression;
  import javax.xml.xpath.XPathExpressionException;
  import javax.xml.xpath.XPathFactory;
  import nl.b3p.brmo.loader.BrmoFramework;
  import nl.b3p.brmo.loader.StagingProxy;
  import nl.b3p.brmo.loader.entity.Bericht;
  import nl.b3p.brmo.loader.util.RsgbTransformer;
  import org.w3c.dom.Document;
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  
  /**
   * @author Meine Toonen
   */
  public class BRPXMLReader extends BrmoXMLReader {
  
    private InputStream in;
    private NodeList nodes = null;
    private int index;
  
    private Templates template;
    private final String pathToXsl = "/xsl/brp-brxml-preprocessor.xsl";
  
    public static final String PREFIX = "NL.BRP.Persoon.";
    private StagingProxy staging;
  
    public BRPXMLReader(InputStream in, Date d, StagingProxy staging) throws Exception {
      this.in = in;
      this.staging = staging;
      setBestandsDatum(d);
      init();
    }
  
    @Override
    public void init() throws Exception {
      soort = BrmoFramework.BR_BRP;
      DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
      factory.setNamespaceAware(true);
      factory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
      factory.setFeature("http://xml.org/sax/features/external-general-entities", false);
      factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
      DocumentBuilder builder = factory.newDocumentBuilder();
      Document doc = builder.parse(in);
  
      TransformerFactory tf = TransformerFactory.newInstance();
      tf.setURIResolver(
          (href, base) ->
              new StreamSource(RsgbTransformer.class.getResourceAsStream("/xsl/" + href)));
  
      Source xsl = new StreamSource(BRPXMLReader.class.getResourceAsStream(pathToXsl));
      this.template = tf.newTemplates(xsl);
  
      nodes = doc.getDocumentElement().getChildNodes();
      index = 0;
    }
  
    @Override
    public boolean hasNext() throws Exception {
      return index < nodes.getLength();
    }
  
    @Override
   public Bericht next() throws Exception {
     Node n = nodes.item(index);
     index++;
     String object_ref = getObjectRef(n);
     StringWriter sw = new StringWriter();
     Bericht old =
         staging.getPreviousBericht(object_ref, getBestandsDatum(), -1L, new StringBuilder());
 
     // kijk hier of dit bericht een voorganger heeft: zo niet, dan moet niet de preprocessor
     // template gebruikt worden, maar de gewone.
 
     Transformer t;
 
     if (old != null) {
       t = this.template.newTransformer();
     } else {
       t = TransformerFactory.newInstance().newTransformer();
     }
 
     t.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
     t.transform(new DOMSource(n), new StreamResult(sw)); // new StreamResult(outputStream));
 
     Map<String, String> bsns = extractBSN(n);
 
     String el = getXML(bsns);
     String origXML = sw.toString();
     String brXML = "<root>" + origXML;
     brXML += el + "</root>";
     Bericht b = new Bericht(brXML);
     b.setBrOrgineelXml(origXML);
     b.setVolgordeNummer(index);
     b.setObjectRef(object_ref);
     b.setSoort(BrmoFramework.BR_BRP);
     b.setDatum(getBestandsDatum());
     return b;
   }
 
   private String getObjectRef(Node n) {
     NodeList childs = n.getChildNodes();
     String hash = null;
     for (int i = 0; i < childs.getLength(); i++) {
       Node child = childs.item(i);
       String name = child.getNodeName();
       if (name.contains("bsn-nummer")) {
         hash = child.getTextContent();
         hash = getHash(hash);
         break;
       }
     }
     return PREFIX + hash;
   }
 
   /**
    * maakt een map met bsn,bsnhash.
    *
    * @param n document node met bsn-nummer
    * @return hashmap met bsn,bsnhash
    * @throws XPathExpressionException if any
    */
   public Map<String, String> extractBSN(Node n) throws XPathExpressionException {
     Map<String, String> hashes = new HashMap<>();
 
     XPathFactory xPathfactory = XPathFactory.newInstance();
     XPath xpath = xPathfactory.newXPath();
     XPathExpression expr = xpath.compile("//*[local-name() = 'bsn-nummer']");
     NodeList nodelist = (NodeList) expr.evaluate(n, XPathConstants.NODESET);
     for (int i = 0; i < nodelist.getLength(); i++) {
       Node bsn = nodelist.item(i);
       String bsnString = bsn.getTextContent();
       String hash = getHash(bsnString);
       hashes.put(bsnString, hash);
     }
     return hashes;
   }
 
   public String getXML(Map<String, String> map) throws ParserConfigurationException {
     String root = "<bsnhashes>";
     for (Entry<String, String> entry : map.entrySet()) {
       if (!entry.getKey().isEmpty() && !entry.getValue().isEmpty()) {
         String hash = entry.getValue();
 
         String el =
             "<" + PREFIX + entry.getKey() + ">" + hash + "</" + PREFIX + entry.getKey() + ">";
         root += el;
       }
     }
     root += "</bsnhashes>";
     return root;
   }
 }