package de.mpg.mpiwg.berlin.mpdl.xml.transform;

import java.io.IOException;
import java.io.StringWriter;
import java.net.URL;

import javax.xml.transform.stream.StreamSource;

import de.mpg.mpiwg.berlin.mpdl.exception.ApplicationException;

import net.sf.saxon.s9api.Processor;
import net.sf.saxon.s9api.QName;
import net.sf.saxon.s9api.SaxonApiException;
import net.sf.saxon.s9api.Serializer;
import net.sf.saxon.s9api.XdmAtomicValue;
import net.sf.saxon.s9api.XdmValue;
import net.sf.saxon.s9api.XsltCompiler;
import net.sf.saxon.s9api.XsltExecutable;
import net.sf.saxon.s9api.XsltTransformer;

public class FragmentTransformer {
  private Processor processor;
  private XsltCompiler xsltCompiler;
  private XsltTransformer xsltFragmentTransformer;
  
  public FragmentTransformer() throws ApplicationException {
    init();
  }
  
  public FragmentTransformer(String xmlFileName) throws ApplicationException {
    init();
    try {
      StreamSource xmlDoc = new StreamSource(xmlFileName); 
      xsltFragmentTransformer.setSource(xmlDoc);  // needs some time for bigger documents
    } catch (SaxonApiException e) {
      throw new ApplicationException(e);
    }
  }
  
  private void init() throws ApplicationException {
    try {
      processor = new Processor(false); 
      xsltCompiler = processor.newXsltCompiler();
      URL getFragmentXslUrl = FragmentTransformer.class.getResource("getFragment.xsl");
      StreamSource xslStreamSource = new StreamSource(getFragmentXslUrl.openStream());
      XsltExecutable xsltExecutable = xsltCompiler.compile(xslStreamSource);
      xsltFragmentTransformer = xsltExecutable.load();
    } catch (SaxonApiException e) {
      throw new ApplicationException(e);
    } catch (IOException e) {
      throw new ApplicationException(e);
    }
  }
  
  public String getFragment(String xmlFileName, String ms1Name, int ms1Pos, String ms2Name, int ms2Pos) throws ApplicationException {
    String pageFragment = null;
    try {
      StreamSource xmlDoc = new StreamSource(xmlFileName); 
      Serializer serializer = new Serializer();
      serializer.setOutputWriter(new StringWriter());
      serializer.setOutputProperty(Serializer.Property.INDENT, "yes");
      xsltFragmentTransformer.setSource(xmlDoc);  // needs some time for bigger documents
      xsltFragmentTransformer.setDestination(serializer);
      QName ms1NameQName = new QName("ms1Name");
      XdmValue ms1NameXdmValue = new XdmAtomicValue(ms1Name);
      QName ms1PositionQName = new QName("ms1Position");
      XdmValue ms1PositionXdmValue = new XdmAtomicValue(ms1Pos);
      QName ms2NameQName = new QName("ms2Name");
      XdmValue ms2NameXdmValue = new XdmAtomicValue(ms2Name);
      QName ms2PositionQName = new QName("ms2Position");
      XdmValue ms2PositionXdmValue = new XdmAtomicValue(ms2Pos);
      xsltFragmentTransformer.setParameter(ms1NameQName, ms1NameXdmValue);
      xsltFragmentTransformer.setParameter(ms1PositionQName, ms1PositionXdmValue);
      xsltFragmentTransformer.setParameter(ms2NameQName, ms2NameXdmValue);
      xsltFragmentTransformer.setParameter(ms2PositionQName, ms2PositionXdmValue);
      xsltFragmentTransformer.transform();  // needs some time for bigger documents
      pageFragment = serializer.getOutputDestination().toString();
    } catch (Exception e) {
      throw new ApplicationException(e);
    }
    return pageFragment;
  }

  public String getFragment(String ms1Name, int ms1Pos, String ms2Name, int ms2Pos) throws ApplicationException {
    String pageFragment = null;
    try {
      Serializer serializer = new Serializer();
      serializer.setOutputWriter(new StringWriter());
      serializer.setOutputProperty(Serializer.Property.INDENT, "yes");
      xsltFragmentTransformer.setDestination(serializer);
      QName ms1NameQName = new QName("ms1Name");
      XdmValue ms1NameXdmValue = new XdmAtomicValue(ms1Name);
      QName ms1PositionQName = new QName("ms1Position");
      XdmValue ms1PositionXdmValue = new XdmAtomicValue(ms1Pos);
      QName ms2NameQName = new QName("ms2Name");
      XdmValue ms2NameXdmValue = new XdmAtomicValue(ms2Name);
      QName ms2PositionQName = new QName("ms2Position");
      XdmValue ms2PositionXdmValue = new XdmAtomicValue(ms2Pos);
      xsltFragmentTransformer.setParameter(ms1NameQName, ms1NameXdmValue);
      xsltFragmentTransformer.setParameter(ms1PositionQName, ms1PositionXdmValue);
      xsltFragmentTransformer.setParameter(ms2NameQName, ms2NameXdmValue);
      xsltFragmentTransformer.setParameter(ms2PositionQName, ms2PositionXdmValue);
      xsltFragmentTransformer.transform();  // needs some time for bigger documents
      pageFragment = serializer.getOutputDestination().toString();
    } catch (Exception e) {
      throw new ApplicationException(e);
    }
    return pageFragment;
  }


}