protected final Log LOGGER = LogFactory.getLog(getClass());

	@Autowired
	private UserRepository userRepository;

	@Autowired
	private PasswordEncoder passwordEncoder;

	@Autowired
	private AuthenticationManager authenticationManager;

	// Funkcija koja na osnovu username-a iz baze vraca objekat User-a
	@Override
	public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
		User user = userRepository.findByUsername(username);
		if (user == null) {
			throw new UsernameNotFoundException(String.format("No user found with username '%s'.", username));
		} else {
			return user;
		}
	}

	// Funkcija pomocu koje korisnik menja svoju lozinku
	public void changePassword(String oldPassword, String newPassword) {

		Authentication currentUser = SecurityContextHolder.getContext().getAuthentication();
		String username = currentUser.getName();

		if (authenticationManager != null) {
			LOGGER.debug("Re-authenticating user '" + username + "' for password change request.");

			authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(username, oldPassword));
		} else {
			LOGGER.debug("No authentication manager set. can't change Password!");

			return;
		}

		LOGGER.debug("Changing password for user '" + username + "'");

		User user = (User) loadUserByUsername(username);

		// pre nego sto u bazu upisemo novu lozinku, potrebno ju je hesirati
		// ne zelimo da u bazi cuvamo lozinke u plain text formatu
		user.setPassword(passwordEncoder.encode(newPassword));
		userRepository.save(user);

	}