package org.biomediator.xml;

import java.io.*;
import java.util.*;
import java.io.PrintWriter;

import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.SAXParser;
import org.xml.sax.*;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.*;

public class XMLAttributeParser extends DefaultHandler implements XMLParserHandler {

  public Stack locStack = new Stack();
  public String content = null;
  public HashMap attributes = null;
  public InputStream inputStream = null;
  public boolean unprocessedContent = false;
  public XMLParserHandler parserHandler = null;
  public StringBuffer strBuf = null;

  public XMLAttributeParser(InputStream input, StringBuffer lineBuf) {

    inputStream = input;
    strBuf = lineBuf;
    parserHandler = this;
  }

  public StringBuffer parseData() {

    DefaultHandler handler = this;
    SAXParserFactory factory = SAXParserFactory.newInstance();
    
    try {
      factory.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
      SAXParser saxParser = factory.newSAXParser();
      saxParser.parse(inputStream, handler);
      inputStream.close();
     
    }
    catch (Throwable t) {
      System.err.println(t);
      t.printStackTrace();
    }
    return strBuf;
  }

  public void processCharacters(String content) {
  }
  
  public void processEnd(String path) {
  }
  
  public void processStart(String path) {
  }
  
  public void startElement(String namespaceURI, String lName, String qName, Attributes attrs)
      throws SAXException {

	  boolean isElement = false;
    // Enter new scope.
    locStack.push(qName);

    // Read any attributes that are part of the new scope's open tag.
    int attrsLength = attrs.getLength();
    if (attrsLength == 0) {
    	isElement = true;
    }
    attributes = new HashMap();
    
    strBuf.append("<" + qName + ">" + "\n");
    if (!isElement){    	
    	strBuf.append("<ATTRIBUTE_EXTRACTION>" + "\n");
    }
  
    for (int i = 0; i < attrsLength; i++) {
      attributes.put(attrs.getQName(i), attrs.getValue(i));
      strBuf.append("<");
      strBuf.append(attrs.getQName(i));
      strBuf.append(">" + "\n");
      strBuf.append("<![CDATA[" + attrs.getValue(i) + "]]>");
      strBuf.append("\n");
      strBuf.append("</");
      strBuf.append(attrs.getQName(i));
      strBuf.append(">" + "\n");
      
    }
    if (!isElement){    	
    	strBuf.append("</ATTRIBUTE_EXTRACTION>" + "\n");
    }
    // Process any START key rules intended for this new scope.
    processStart(getLocation());
  }

  public void characters(char buf[], int offset, int len)
      throws SAXException {


    // Read character data from the CDATA portion of an XML tag.
    // Note that this method may be called more than once per CDATA tag!
    if (content == null) {
      content = (new String(buf, offset, len)).trim();
      unprocessedContent = true;
    }
    else {
      content = content + (new String(buf, offset, len));
    }
    
  }
  


  public void endElement(String namespaceURI, String sName, String qName)
      throws SAXException {

    // Make sure to process any leftover character data before existing current scope.
    if (unprocessedContent) {
      content = content.trim();
      //strBuf.append("length is " + content.length() + "\n");
      if (content.length()>0){
    	  strBuf.append("<![CDATA[" + content + "]]>\n");
      }
    }

    // Process any END key rules intended for the current scope.
    processEnd(getLocation());
    
    // Clear the character buffer.
    unprocessedContent = false;
    content = null;


    strBuf.append("</" + qName + ">" + "\n");
    // Exit current scope.
    locStack.pop();
  }
  
  public String getLocation() {

    StringBuffer locBuf = new StringBuffer();
    for (int i = 0; i < locStack.size(); i++)
      locBuf.append("/" + (String)locStack.elementAt(i));

    return(locBuf.toString());
  }
}