package org.myrobotlab.service;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.myrobotlab.document.connector.AbstractConnector;
import org.myrobotlab.document.connector.ConnectorState;
import org.myrobotlab.document.transformer.ConnectorConfig;
import org.myrobotlab.document.xml.MRLChunkingXMLHandler;
import org.myrobotlab.document.xml.RecordingInputStream;
import org.myrobotlab.framework.ServiceType;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

/**
 * 
 * XMLConnector - This will parse a large xml file into many sub documents based
 * on the XMLRoot path. All of the xml under that path will be created as a
 * document that can be published to the doc pipeline, or other
 * DocumentListener.
 */
public class XMLConnector extends AbstractConnector {

  private static final long serialVersionUID = 1L;

  private String filename = "D:\\data\\wikipedia\\enwiki-20160113-pages-articles-multistream.xml";
  private String xmlRootPath = "/page";
  private String xmlIDPath = "/page/id";
  private String docIDPrefix = "doc_";
  // TODO: wire in so we can interrupt and stop the crawler.
  // private boolean interrupted = false;

  public XMLConnector(String name) {
    super(name);
  }

  @Override
  public void setConfig(ConnectorConfig config) {
    // TODO Auto-generated method stub
    log.info("Set Config not yet implemented");
  }

  @Override
  public void startCrawling() {
    // avoid buffer overruns on the outbox.. connectors shouldn't drop messages.
    // (or run out of memory)
    this.outbox.setBlocking(true);
    state = ConnectorState.RUNNING;
    SAXParserFactory spf = SAXParserFactory.newInstance();
    // spf.setNamespaceAware(false); ? Expose this?
    spf.setNamespaceAware(true);
    SAXParser saxParser = null;
    try {
      saxParser = spf.newSAXParser();
    } catch (ParserConfigurationException | SAXException e) {
      // TODO Auto-generated catch block
      log.warn("SAX Parser Error {}", e);
    }

    try {
      XMLReader xmlReader = saxParser.getXMLReader();
      MRLChunkingXMLHandler xmlHandler = new MRLChunkingXMLHandler();
      xmlHandler.setConnector(this);
      xmlHandler.setDocumentRootPath(xmlRootPath);
      xmlHandler.setDocumentIDPath(xmlIDPath);
      xmlHandler.setDocIDPrefix(docIDPrefix);
      xmlReader.setContentHandler(xmlHandler);

      FileInputStream fis = new FileInputStream(new File(filename));
      RecordingInputStream ris = new RecordingInputStream(fis);
      InputSource xmlSource = new InputSource(ris);
      xmlHandler.setRis(ris);

      xmlReader.parse(xmlSource);
      // xmlReader.parse(convertToFileURL(filename));
    } catch (IOException | SAXException e) {
      // TODO Auto-generated catch block
      log.warn("SAX Parser Error {}", e);
    }
    state = ConnectorState.STOPPED;

  }

  @Override
  public void stopCrawling() {
    // Stop crawling! (maybe flush?)
    // interrupted = true;

  }

  public String getFilename() {
    return filename;
  }

  public void setFilename(String filename) {
    this.filename = filename;
  }

  public String getXmlRootPath() {
    return xmlRootPath;
  }

  public void setXmlRootPath(String xmlRootPath) {
    this.xmlRootPath = xmlRootPath;
  }

  public String getXmlIDPath() {
    return xmlIDPath;
  }

  public void setXmlIDPath(String xmlIDPath) {
    this.xmlIDPath = xmlIDPath;
  }

  public String getDocIDPrefix() {
    return docIDPrefix;
  }

  public void setDocIDPrefix(String docIDPrefix) {
    this.docIDPrefix = docIDPrefix;
  }

  /**
   * This static method returns all the details of the class without it having
   * to be constructed. It has description, categories, dependencies, and peer
   * definitions.
   * 
   * @return ServiceType - returns all the data
   * 
   */
  static public ServiceType getMetaData() {
    ServiceType meta = new ServiceType(XMLConnector.class.getCanonicalName());
    meta.addDescription("This is an XML Connector that will parse a large xml file into many small xml documents");
    meta.addCategory("data");
    return meta;
  }

}