package de.cdauth.jspwiki;

import java.sql.*;
import com.ecyrd.jspwiki.*;
import com.ecyrd.jspwiki.plugin.*;
import java.util.*;
import javax.servlet.http.*;

public class HitCounter implements WikiPlugin
{
	private static final String databasePath = "jdbc:postgresql://localhost/jspwiki";
	private static final String databaseUsername = "postgres";
	private static final String databasePassword = "";
	private static final String databaseDriver = "org.postgresql.Driver";
	
	private static final int timeout = 7200;
	
	private static final String PARAM_NAME = "name";
	private static final String PARAM_HIDDEN = "hidden";
	private static final String PARAM_INCREASE = "increase";
	private static final String PARAM_HITS = "hits";

	
	private Connection databaseConnection = null;
	private String name = null;
	private boolean hidden = false;
	private boolean increase = true;
	private boolean hits = false;
	
	public String execute(WikiContext context, Map ParameterMap)
		throws PluginException
	{
		int c = 0;
		
		PreparedStatement statement = null;
		ResultSet result = null;
		
		HttpSession s = context.getHttpRequest().getSession();
		String sid = null;
		if(s != null)
			sid = s.getId();
		
		java.util.Date now = new java.util.Date();
		
		name = (String) ParameterMap.get(PARAM_NAME);
		if(name == null)
			name = context.getPage().getName();
		String hidden_param = (String) ParameterMap.get(PARAM_HIDDEN);
		if(hidden_param != null && (hidden_param.equals("yes") || hidden_param.equals("true")))
			hidden = true;
		String increase_param = (String) ParameterMap.get(PARAM_INCREASE);
		if(increase_param != null && (!increase_param.equals("yes") && !increase_param.equals("true")))
			increase = false;
		String hits_param = (String) ParameterMap.get(PARAM_HITS);
		if(hits_param != null && (hits_param.equals("yes") || hits_param.equals("true")))
			hits = true;

		try
		{
			Class.forName(databaseDriver).newInstance();
			databaseConnection = DriverManager.getConnection(databasePath, databaseUsername, databasePassword);

			statement = databaseConnection.prepareStatement("SELECT COUNT(*) AS c_count FROM t_hitcounter WHERE c_name = ?;");
			statement.setString(1, name);
			result = statement.executeQuery();
			result.next();
			int in = result.getInt("c_count");
			if(in > 0)
			{
				statement = databaseConnection.prepareStatement("SELECT c_hits FROM t_hitcounter WHERE c_name = ?;");
				statement.setString(1, name);
				result = statement.executeQuery();
				result.next();
				c = result.getInt("c_hits");
			}
			
			// Check if number has to be increased
			boolean must_increase = true;
			if(!increase) must_increase = false;
			else if(!hits && sid != null)
			{
				statement = databaseConnection.prepareStatement("SELECT COUNT(*) AS c_count FROM t_hittrace WHERE c_name = ? AND c_sid = ?;");
				statement.setString(1, name);
				statement.setString(2, sid);
				result = statement.executeQuery();
				result.next();
				int seen = result.getInt("c_count");
				if(seen > 0)
				{
					statement = databaseConnection.prepareStatement("UPDATE t_hittrace SET c_lastseen = ? WHERE c_name = ? AND c_sid = ?;");
					must_increase = false;
				}
				else
					statement = databaseConnection.prepareStatement("INSERT INTO t_hittrace ( c_lastseen, c_name, c_sid ) VALUES ( ?, ?, ?);");
				statement.setInt(1, Math.round(now.getTime()/1000));
				statement.setString(2, name);
				statement.setString(3, sid);
				statement.executeUpdate();
			}
			
			if(must_increase)
			{
				c++;
				if(in > 0)
					statement = databaseConnection.prepareStatement("UPDATE t_hitcounter SET c_hits = "+c+" WHERE c_name = ?;");
				else
					statement = databaseConnection.prepareStatement("INSERT INTO t_hitcounter ( c_name, c_hits ) VALUES ( ?, "+c+" );");
				statement.setString(1, name);
				statement.executeUpdate();
			}
			
			// Cleanup database
			statement = databaseConnection.prepareStatement("DELETE FROM t_hittrace WHERE c_lastseen < ?;");
			statement.setInt(1, Math.round(now.getTime()/1000)-timeout);
			statement.executeUpdate();
		}
		catch(ClassNotFoundException e)
		{
			throw new PluginException("Database driver not found: "+e);
		}
		catch(InstantiationException e)
		{
			throw new PluginException("Could not load database driver: "+e);
		}
		catch(IllegalAccessException e)
		{
			throw new PluginException("Could not load database driver: "+e);
		}
		catch(SQLException e)
		{
			throw new PluginException("Database error: "+e);
		}

		String ret = "";
		if(!hidden)
			ret = new Integer(c).toString();
		return ret;
	}
}