import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import jdbm.htree.*;
import jdbm.*;
import jdbm.helper.*;

public class dbm extends HttpServlet{
	
	String DATABASE = "DBvisitors1";
    String HTREE_NAME = "visitors1";
	Properties props;
	RecordManager  recman;
	HTree table;
    String strDate;
    
    /*Skapar databasen "DBvisitors1" om den inte redan finns
     * Skapar hashtrŠdet (tabellen) "visitors1" om den inte redan finns
     */
	public void init() throws ServletException{
		props = new Properties();
		try{
			recman = RecordManagerFactory.createRecordManager(DATABASE, props);
			long recid = recman.getNamedObject(HTREE_NAME);
			if (recid != 0)
				table = HTree.load(recman, recid);
			else{
				table = HTree.createInstance(recman);
				recman.setNamedObject(HTREE_NAME, table.getRecid());
			}
		}catch(IOException e){}
	}
	
	//stŠnger databasen "DBvisitors"
	public void destroy(){
		try{
			recman.close();
		}catch(IOException e){}
		super.destroy();
	}

	//Skriver ut tabellen i form av en strŠng
	public String visitorsToString() throws IOException{
		FastIterator iter = table.keys();
        String key = (String)iter.next();
        String value = null;
        if (key != null)
        	value = (String)table.get(key);
        String strOutput = "";
        while (key != null) {
        	value = (String)table.get(key);
        	strOutput = strOutput + key + "\n" + value + "\n\n";
            key = (String)iter.next();
        }
        return strOutput;
	}
	
	//LŠgger till en ny visitor och skriver ut tabellen
	public void doGet(HttpServletRequest req, HttpServletResponse res) throws IOException, ServletException{
		PrintWriter out = res.getWriter();
		res.setContentType("text/plain");
		Calendar cal = Calendar.getInstance();
		strDate = String.format("Time: %1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS", cal);
		table.put(strDate, "Remote Address: " + req.getRemoteAddr() + "\nRemote user agent" + req.getHeader("user-agent"));
		recman.commit();
		out.println(visitorsToString());
		
	}
}