package questionnaire;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import  org.w3c.dom.Document;
import  org.w3c.dom.Element;

/**
 * @author tsuhtan
 */
public class SummaryServlet extends HttpServlet
{
	/**
	 * 今回は特にやることなし^^;
	 * @see javax.servlet.Servlet#init(javax.servlet.ServletConfig)
	 */
	public void init (ServletConfig sc) throws ServletException
	{
		super.init (sc);
	}

	/**
	 * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
	 */
	protected void doGet(HttpServletRequest req, HttpServletResponse res)
		throws ServletException, IOException
	{
		this.doPost(req, res);
	}
		/**
		 * @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
		 */
		protected void doPost(HttpServletRequest req, HttpServletResponse res)
			throws ServletException, IOException
		{
		Document response_document = createResponseAsDocument (req);
		sendResponseDocument (req, res, response_document);
	}

	private	Document	createResponseAsDocument (HttpServletRequest req)
	{
		try {
			DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
			DocumentBuilder db = dbf.newDocumentBuilder();
			Document document = db.newDocument();
			Element status = document.createElement ("status");
			status.appendChild (document.createTextNode ("OK"));
			Element root = document.createElement ("root");
			root.appendChild (status);
			document.appendChild (root);

			return document;
		} catch (Exception e) {
			throw new RuntimeException (e);
		}
	}

	private	void	sendResponseDocument (HttpServletRequest req, HttpServletResponse res, Document document)
	{
		try {
			TransformerFactory tf = TransformerFactory.newInstance();
			Transformer transformer = tf.newTransformer();
			DOMSource ds = new DOMSource (document);
			StringWriter string = new StringWriter();
			StreamResult sr = new StreamResult (string);
			transformer.transform (ds, sr);

			String s = string.toString();
			int length = s.getBytes().length;
			res.setContentType ("text/plain");
			res.setContentLength (length + 2);
			PrintWriter pw = res.getWriter();
			pw.print (s + "\r\n");
			pw.flush();

		} catch (Exception e) {
			throw new RuntimeException (e);
		}		
	}
}