package org.openslx.imagemaster.server;

import java.io.File;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;

import org.apache.ftpserver.FtpServer;
import org.apache.ftpserver.FtpServerFactory;
import org.apache.ftpserver.ftplet.Authority;
import org.apache.ftpserver.ftplet.FtpException;
import org.apache.ftpserver.ftplet.Ftplet;
import org.apache.ftpserver.ftplet.UserManager;
import org.apache.ftpserver.listener.ListenerFactory;
import org.apache.ftpserver.usermanager.PropertiesUserManagerFactory;
import org.apache.ftpserver.usermanager.SaltedPasswordEncryptor;
import org.apache.ftpserver.usermanager.impl.BaseUser;
import org.apache.ftpserver.usermanager.impl.WritePermission;
import org.apache.log4j.Logger;
import org.openslx.imagemaster.Globals;
import org.openslx.imagemaster.thrift.iface.FtpCredentials;
import org.openslx.imagemaster.util.RandomString;

public class MasterFtpServer implements Runnable {
	private static Logger log = Logger.getLogger( MasterFtpServer.class );
	private FtpServer server;
	private UserManager userManager;
	// key: serverSessionId, value: FtpCredentials
	public final HashMap<String, FtpCredentials> users = new HashMap<>();
	// key: ftpUsername, value: createTime
	public final HashMap<String, Date> timeouts = new HashMap<>();
	
	public MasterFtpServer(int port, String adminUsername, String adminPassword, String ftproot) {
		FtpServerFactory serverFactory = new FtpServerFactory();
		ListenerFactory factory = new ListenerFactory();
		// set the port of the listener
		factory.setPort(port);
		
		// replace the default listener
		serverFactory.addListener("default", factory.createListener());
		
		// create user manager
	    PropertiesUserManagerFactory userManagerFactory = new PropertiesUserManagerFactory();
	    userManagerFactory.setFile(new File("src/main/properties/ftp.properties"));
	    userManagerFactory.setPasswordEncryptor(new SaltedPasswordEncryptor());
	    userManager = userManagerFactory.createUserManager();
		
		// create new admin user
	    //addUser(adminUsername, adminPassword, ftproot, true);
		serverFactory.setUserManager(userManager);
		
		// add the Ftplet
		HashMap<String, Ftplet> map = new HashMap<String, Ftplet>();
		map.put("Ftplet1", new MasterFtplet());
		serverFactory.setFtplets(map);
		
		// start the server
		server = serverFactory.createServer();
	}

	public FtpCredentials addUser(final String serverSessionId) {
	    // TODO: enable SSL
		
		FtpCredentials ftpCredentials = null;
		
		String generatedUser = RandomString.generate(10, false);
		String generatedPass = RandomString.generate(16, true);
		
		String dir = Globals.properties.getProperty(Globals.ftpBaseDir) + "/"
				+ generatedUser + "/";
		
		if (!new File(dir).mkdir()) {
			return ftpCredentials;
		}

	    BaseUser user = new BaseUser();
	    user.setName(generatedUser);
	    user.setPassword(generatedPass);
	    user.setHomeDirectory(dir);

	    List<Authority> authorities = new ArrayList<Authority>();
	    authorities.add(new WritePermission());
	    user.setAuthorities(authorities);

	    try {
	    	userManager.save(user);
	    	ftpCredentials = new FtpCredentials(generatedUser, generatedPass);
	    	users.put(serverSessionId, ftpCredentials);
	    	timeouts.put(ftpCredentials.username, new Date());
	    } catch (FtpException e) {
	    }
	    
		log.info("Generated user/pass: " + generatedUser + "\t"
				+ generatedPass + "\n with home dir: " + dir);
	    
	    return ftpCredentials;
	}
	
	public boolean removeUser(final String serverSessionId) {
		if (!users.containsKey(serverSessionId)) return false;
		
		try {
			userManager.delete(users.get(serverSessionId).username);
			// remove user from both maps
			timeouts.remove(users.remove(serverSessionId).username);
			return true;
		} catch (FtpException e) {
			return false;
		}
	}
	
	public FtpCredentials getCredentialsFromSessionId(String serverSessionId) {
		return users.get(serverSessionId);
	}

	@Override
	public void run() {
		try {
			log.info( "Starting FTP Sever" );
			server.start();
		} catch (FtpException e1) {
			e1.printStackTrace();
		}
	}
}