package ajaxstutter;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author Ravitej Syamala 
 */

// Wiring:
// - ajaxstutter.html      : Starting point
// - ajaxClient.js         : Javascript, used by ajaxstutter.html for ajax enabling
// - ajaxstutter.java      : Called from ajaxClient.js
// - ajaxstutterClass.java : Called from ajaxstutter as a static (ajaxstutterClass.checkStutter())
// DEPLOY:
// - ajaxstutter.html and ajaxClient.js must be in webapps/ajaxstutter
//   (Same level as WEB-INF)

public class ajaxstutter extends HttpServlet
{
    private static final long serialVersionUID = -3509437421722952331L;

    /**
     * Allows logging into the Catalina logs if needed.     * 
     * @param message
     * @throws IOException
     */
    private void logCrud (String message) throws IOException
    {
        getServletContext().log (message);
    }

    /*
     * (non-Javadoc)
     * 
     * @see javax.servlet.http.HttpServlet#doGet (javax.servlet.http.HttpServletRequest,
     *      javax.servlet.http.HttpServletResponse)
     */
    protected void doGet (HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException
    {
        // find our form text in the request
        String targetId = req.getParameter ("testPassage");
        // content type is XML, not HTML
        resp.setContentType ("text/xml");
        // no caching of results by client, forces reload
        resp.setHeader ("Cache-Control", "no-cache");

        // if there is no stutter, send a simple message.
        if (((targetId != null) && !ajaxstutterClass.isStutter (targetId))) {
            resp.getWriter().write ("<message> No stutters found... </message>");
        } else
        {
            // send a list of stutters, these are delimited by special symbols
            // although more xml could be used, replaceAll operation in javascript 
            // ends up being less work/code. 
            resp.getWriter().write ("<message>");
            ajaxstutterClass.checkStutter (targetId, resp);
            resp.getWriter().write ("</message>");
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see javax.servlet.http.HttpServlet#doPost (javax.servlet.http.HttpServletRequest,
     *      javax.servlet.http.HttpServletResponse)
     */
    protected void doPost (HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException
    {
        // GET methods work best with AJAX in this scenario
        doGet (req, resp);
    }
}