@Configuration
@EnableWebSecurity
@EnableOAuth2Client
public class SecurityConfig extends WebSecurityConfigurerAdapter
{

    @Autowired
    private UserDao userDao;

    @Autowired
    private PasswordEncoder passwordEncoder;

    @Autowired
    private AuthProvider authProvider;

    @Autowired
    @Qualifier("oauth2ClientContext")
    private OAuth2ClientContext oAuth2ClientContext;

    @Bean
    PasswordEncoder passwordEncoder()
    {
        return new BCryptPasswordEncoder();
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth)
    {
        auth.authenticationProvider(authProvider);
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception
    {
        http.addFilterBefore(ssoFilter(), UsernamePasswordAuthenticationFilter.class);

        http
                .csrf().disable()
                .authorizeRequests()
                .antMatchers("/resources/**", "/", "/login**", "/registration", "main").permitAll()
                .anyRequest().authenticated()
                .and().formLogin().loginPage("/login")
                .defaultSuccessUrl("/main").failureUrl("/login?error").permitAll()
                .and().logout().logoutSuccessUrl("/").permitAll();
    }

    @Bean
    public FilterRegistrationBean oAuth2ClientFilterRegistration(OAuth2ClientContextFilter oAuth2ClientContextFilter)
    {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(oAuth2ClientContextFilter);
        registration.setOrder(-100);
        return registration;
    }

    private Filter ssoFilter()
    {
        CompositeFilter filter = new CompositeFilter();
        List<Filter> filters = new ArrayList<>();
        filters.add(ssoFilter(google(), "/login/google"));
        filters.add(ssoFilter(discord(), "/login/discord"));
        filters.add(ssoFilter(vk(), "/login/vk"));
        filter.setFilters(filters);
        return filter;
    }

    private Filter ssoFilter(ClientResources client, String path) {
        OAuth2ClientAuthenticationProcessingFilter filter = new OAuth2ClientAuthenticationProcessingFilter(path);
        OAuth2RestTemplate template = new OAuth2RestTemplate(client.getClient(), oAuth2ClientContext);

        OAuth2AccessTokenSupport authAccessProvider = new AuthorizationCodeAccessTokenProvider();

        AccessTokenProvider accessTokenProvider = new AccessTokenProviderChain(
                Arrays.<AccessTokenProvider> asList((AuthorizationCodeAccessTokenProvider)authAccessProvider)
        );
        template.setAccessTokenProvider(accessTokenProvider);

        ClientHttpRequestFactory requestFactory = new DiscordHttpRequestFactory();
        authAccessProvider.setRequestFactory(requestFactory);
        template.setRequestFactory(requestFactory);

        filter.setRestTemplate(template);
        CustomUserInfoTokenServices tokenServices = new CustomUserInfoTokenServices(
                client.getResource().getUserInfoUri(), client.getClient().getClientId());
        tokenServices.setRestTemplate(template);

        tokenServices.setUserDao(userDao);
        tokenServices.setPasswordEncoder(passwordEncoder);

        filter.setTokenServices(tokenServices);
        return filter;
    }

    class ClientResources {

        @NestedConfigurationProperty
        private AuthorizationCodeResourceDetails client = new AuthorizationCodeResourceDetails();

        @NestedConfigurationProperty
        private ResourceServerProperties resource = new ResourceServerProperties();

        public AuthorizationCodeResourceDetails getClient() {
            return client;
        }

        public ResourceServerProperties getResource() {
            return resource;
        }
    }

    @Bean
    @ConfigurationProperties("google")
    public ClientResources google()
    {
        return new ClientResources();
    }

    @Bean
    @ConfigurationProperties("discord")
    public ClientResources discord()
    {
        return new ClientResources();
    }

    @Bean
    @ConfigurationProperties("vk")
    public ClientResources vk()
    {
        return new ClientResources();
    }
}