package org.owasp.webgoat;

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

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.owasp.webgoat.lessons.AbstractLesson;
import org.owasp.webgoat.session.Course;
import org.owasp.webgoat.session.WebSession;

/**
 *  Copyright (c) 2002 Free Software Foundation developed under the custody of the Open Web
 *  Application Security Project (http://www.owasp.org) This software package is published by OWASP
 *  under the GPL. You should read and accept the LICENSE before you use, modify and/or redistribute
 *  this software.
 *
 * @author     Jeff Williams <a href="http://www.aspectsecurity.com">Aspect Security</a>
 * @created    October 28, 2003
 */
public class LessonSource extends HammerHead
{

	/**
	 *  Description of the Field
	 */
	//protected WebSession tempSession;
	
	public final static String START_SOURCE_SKIP = "START_OMIT_SOURCE";
	public final static String END_SOURCE_SKIP = "END_OMIT_SOURCE";

	/**
	 *  Description of the Method
	 *
	 * @param  request               Description of the Parameter
	 * @param  response              Description of the Parameter
	 * @exception  IOException       Description of the Exception
	 * @exception  ServletException  Description of the Exception
	 */
	public void doPost( HttpServletRequest request, HttpServletResponse response ) throws IOException, ServletException
	{
		String source = null;  

		try
		{
			//System.out.println( "Entering doPost: " );
			//System.out.println( "	- request "   + request);
			//System.out.println( "	- principle: "   + request.getUserPrincipal() );
			//setCacheHeaders(response, 0);
			WebSession session = (WebSession) request.getSession( true ).getAttribute( WebSession.SESSION );
			session.update(request, response, this.getServletName()); // FIXME: Too much in this call.
			
			// Get the Java source of the lesson.  FIXME: Not needed
			source = getSource( session );
						
			int scr = session.getCurrentScreen();
			Course course = session.getCourse();
			AbstractLesson lesson = course.getLesson( session, scr, AbstractLesson.USER_ROLE );				
			lesson.getLessonTracker( session ).setViewedSource(true);
		}
		catch ( Throwable t )
		{
			t.printStackTrace();
			log( "ERROR: " + t );						
		}
		finally
		{
			try
			{
				this.writeSource(source, response );
			}
			catch ( Throwable thr )
			{
				thr.printStackTrace();
				log( request, "Could not write error screen: " + thr.getMessage() );
			}
			//System.out.println( "Leaving doPost: " );

		}
	}


	protected WebSession updateSession_DELETEME( HttpServletRequest request, HttpServletResponse response, ServletContext context )
	{
		HttpSession hs;
		hs = request.getSession( true );

		//System.out.println( "Entering Session_id: " + hs.getId() );
		// dumpSession( hs );

		// Make a temporary session to avoid the concurreny issue 
		// in WebSession
		WebSession session = new WebSession( this, context );

		WebSession realSession = null;
		Object o = hs.getAttribute( WebSession.SESSION );

		if ( ( o != null ) && o instanceof WebSession )
		{
			realSession = (WebSession) o;
		}
		session.setCurrentScreen( realSession.getCurrentScreen());
		session.setCourse( realSession.getCourse() );
		session.setRequest( request );

		// to authenticate
		//System.out.println( "Leaving Session_id: " + hs.getId() );
		//dumpSession( hs );
		return ( session );
	}


	/**
	 *  Description of the Method
	 *
	 * @param  s  Description of the Parameter
	 * @return    Description of the Return Value
	 */
	protected String getSource( WebSession s )
	{

		String source = null;
		int scr = s.getCurrentScreen();
		Course course = s.getCourse();

		if ( s.isUser() || s.isChallenge() )		
		{
			
			AbstractLesson lesson = course.getLesson( s, scr, AbstractLesson.USER_ROLE );

			if ( lesson != null )
			{
				source = lesson.getSource(s);	
			}
		}
        if ( source == null )
        {
            return "Source code is not available. Contact webgoat@aspectsecurity.com";
        }
		return ( source.replaceAll("(?s)" + START_SOURCE_SKIP + ".*" + END_SOURCE_SKIP, "Code Section Deliberately Omitted") );
	}



	/**
	 *  Description of the Method
	 *
	 * @param  s                Description of the Parameter
	 * @param  response         Description of the Parameter
	 * @exception  IOException  Description of the Exception
	 */
	protected void writeSource( String s, HttpServletResponse response ) throws IOException
	{
		response.setContentType( "text/html" );

		PrintWriter out = response.getWriter();

		if ( s == null )
		{
			s = new String();			
		}

		out.print(s);
		out.close();
	}
}