package org.openslx.imagemaster.ftp;

import java.io.IOException;

import org.apache.ftpserver.ftplet.FtpException;
import org.apache.ftpserver.ftplet.FtpReply;
import org.apache.ftpserver.ftplet.FtpRequest;
import org.apache.ftpserver.ftplet.FtpSession;
import org.apache.ftpserver.ftplet.Ftplet;
import org.apache.ftpserver.ftplet.FtpletContext;
import org.apache.ftpserver.ftplet.FtpletResult;
import org.apache.log4j.Logger;
import org.openslx.imagemaster.App;
import org.openslx.imagemaster.serversession.ServerSessionManager;

public class MasterFtplet implements Ftplet
{
	private static Logger log = Logger.getLogger( MasterFtplet.class );

	@Override
	public void init( FtpletContext ftpletContext ) throws FtpException
	{
		// not used
	}

	@Override
	public void destroy()
	{
		// not used
	}

	@Override
	public FtpletResult beforeCommand( FtpSession session, FtpRequest request )
			throws FtpException, IOException
	{
		if ( session.getUser() != null ) {
			// check if masterserver is still knowing this user 
			if (App.ftpServer.users.containsKey( session.getUser().getName() )) {
				MasterFtpServer.Infos infos = App.ftpServer.users.get( session.getUser().getName() );
				if (infos.getMode() == MasterFtpServer.Mode.DOWNLOADING) {	// filter the downloading clients
					if (request.getCommand().equals("RETR")) {
   					// check if user is getting the right file
   					if (!infos.getFileName().equals(request.getArgument())) {
   						// the client tries to retrieve a file, that he is not allowed to get
   						String organization = ServerSessionManager.getSession( App.ftpServer.users.get( session.getUser().getName() ).getServerSessionId() ).getOrganization();
   						log.info( "A user from organization '" + organization + "' tried to download a file (" + request.getArgument() + "), that he was not allowed to." );
   						throw new FtpException( "550 File unavailable." ); // after the exception, the client will be automatically be disconnected
   					}
					} else if ( request.getCommand().equals( "MLSD" )			// list dirs
								||	request.getCommand().equals( "NSLT" ) 			// list files
								|| request.getCommand().equals( "CWD" )			// change working dir
								) {
						
						// TODO: block all other commands except login and retrieve
						return FtpletResult.DISCONNECT;	// disconnect the client on wrong command
					}
				}
			} else {
				// user is not valid anymore
				throw new FtpException( "430 Invalid username or password." ); // ERROR CODE 430 --> invalid username or password
				// after the exception, the client will be automatically be disconnected
			}
			
		}
		
		return FtpletResult.DEFAULT;
	}

	@Override
	public FtpletResult afterCommand( FtpSession session, FtpRequest request,
			FtpReply reply ) throws FtpException, IOException
	{
		// not used
		return FtpletResult.DEFAULT;
	}

	@Override
	public FtpletResult onConnect( FtpSession session ) throws FtpException,
			IOException
	{
		if (session.getUser() != null) {
			log.info( session.getUser().getName() + " connected" );
		}
		return FtpletResult.DEFAULT;
	}

	@Override
	public FtpletResult onDisconnect( FtpSession session ) throws FtpException,
			IOException
	{
		if (session.getUser() != null) {
			log.info( session.getUser().getName() + " disconnected" );
		}
		return FtpletResult.DEFAULT;
	}

}