// Hit counter servlet, with visitor logging
// http://home.comcast.net/~rowland3

import java.io.*;
import java.text.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

import java.awt.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.awt.image.*;
import com.sun.image.codec.jpeg.*;

class Webpage {
    int count= 0;
    final String referer;
    static String rootpath= null;
    static final String fs= File.separator;

    Webpage(String _referer)  {
	referer= _referer;
	count= 0;

	try { // read the old log
	    LineNumberReader flog= logReader();
	    if (flog!= null) {
		while (flog.readLine()!= null)
		    count++;
		flog.close();
	    }
	} catch (Exception E) { }
    }

    String logspec() {
	String safeRefer= referer.replace('/', '.');
	if (safeRefer.startsWith("http:"))  safeRefer= safeRefer.substring(7);
	return rootpath+ "Feedback."+ safeRefer+ ".log";
    }

    LineNumberReader logReader()  {
	try {
	    String flogspec= logspec();
	    File f= new File(flogspec);
	    if (!f.exists())  return null;
	    Reader flogs= new InputStreamReader(new FileInputStream(flogspec));
	    LineNumberReader flog= new LineNumberReader(flogs);
	    return flog;
	} catch (Exception E) {
	    return null;
	}
    }

    static void flogwrite(OutputStream flog, String s) throws IOException {
	flog.write(s.getBytes());
    }

    void log(HttpServletRequest request) {
	String remoteaddr= request.getRemoteAddr();
	String localaddr= request.getLocalAddr();
	if (!remoteaddr.equals(localaddr) &&
	      !remoteaddr.startsWith("192.168.")) {
	    try {
		FileOutputStream flog= new FileOutputStream(logspec(), true);  // open to append
		java.util.Date d= new java.util.Date();
		flogwrite(flog, d.toString()+ ":\tHost:"+ request.getRemoteHost()+ "\n");
		//flogwrite(flog, "\tReferer:"+ referer+ "\n");
		flog.close();
	    } catch (Exception E) {
		try {
		    FileOutputStream ferr= new FileOutputStream(rootpath+ "Feedback.ERR.log",
								true);  // open to append
		    ferr.write(E.toString().getBytes());
		    ferr.close();
		} catch (Exception E2) { }
	    }
	    count++;
	}
    }
}

public class Feedback extends HttpServlet{
    static final String fs= File.separator;
    static Map webpages= null;
    static BufferedImage[] cache= null;

    // Cribbed from http://www.developer.com/tech/article.php/606551
    protected final static int WIDTH = 50, HEIGHT = 18, FONTSIZE = 14;
    protected final static String FONTNAME = "Arial";

   public void init(ServletConfig config)  throws ServletException   {
      super.init(config);
      webpages= new TreeMap();
      Webpage.rootpath= getServletContext().getRealPath("/")+fs;
      cache= new BufferedImage[100];
   }

    public void doGet(HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException  {
	// Send the image to the client
        OutputStream out = response.getOutputStream();

	String referer= request.getHeader("referer");
	if (referer== null)  referer= "null";
	int ix= referer.indexOf('?');  if (ix< 0)  ix= referer.indexOf('#');
	if (ix> 0)  referer= referer.substring(0, ix);

	Object O= webpages.get(referer);
	Webpage wp= null;
	if (O== null) {
	    wp= new Webpage(referer);
	    webpages.put(referer, wp);
	}  else
	    wp= (Webpage)O;

	// Now for the logging..
	wp.log(request);

	// Now return something to client...
	String pathInfo= request.getPathInfo();
	if (pathInfo==null)  pathInfo="whatever.jpg";
	ix= pathInfo.indexOf("list.html");
	if (ix< 0) {
	    response.setContentType("image/jpeg");
	    BufferedImage img= null;
	    if (wp.count< cache.length)  img= cache[wp.count];
	    if (img==null)  {
		img = draw(Integer.toString(wp.count));
		if (wp.count< cache.length)  cache[wp.count]= img;  // save time next time
	    }
	    JPEGImageEncoder encoder =  JPEGCodec.createJPEGEncoder(out);
	    JPEGEncodeParam param =   encoder.getDefaultJPEGEncodeParam(img);
	    param.setQuality(1.0f,true);
	    encoder.encode(img,param);
	}  else {
	    response.setContentType("text/plain");
	    LineNumberReader flog= wp.logReader();
	    if (flog!= null) {
		while (true) {
		    String line= flog.readLine();
		    if (line== null)  break;
		    line+= "\n";
		    out.write(line.getBytes());
		}
		flog.close();
	    }
	}
	out.close();
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException    {
        doGet(request, response);
    }

    // Based on http://www.developer.com/tech/article.php/606551
    protected BufferedImage draw(String st)
    {
	BufferedImage img = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
	Graphics2D g2 = img.createGraphics();
	g2.setBackground(Color.black);
	g2.clearRect(0,0, WIDTH,HEIGHT);
	g2.setColor(Color.white);
	Font font = new Font(FONTNAME, Font.PLAIN, FONTSIZE);
	g2.setFont(font);
	TextLayout tl = new TextLayout(st,font, g2.getFontRenderContext());
	Rectangle2D r = tl.getBounds();
	// center the text
	tl.draw(g2,(float)((WIDTH- r.getWidth()) / 2),
		(float)(((HEIGHT- r.getHeight()) / 2) + r.getHeight()));
	g2.dispose();
	return img;
    }

}