const express = require('express');
const jwt = require('jsonwebtoken');

const app = express();
app.use(express.json());

// In-memory Token Store
const tokenStore = {};

// Secret key for JWT (replace with a strong, secret key in production)
const secretKey = 'your_secret_key';

// Middleware to verify JWT
function verifyToken(req, res, next) {
    const token = req.headers.authorization;

    if (!token) {
        return res.status(403).json({ message: 'No token provided' });
    }

    jwt.verify(token, secretKey, (err, decoded) => {
        if (err) {
            return res.status(401).json({ message: 'Failed to authenticate token' });
        }

        req.user = decoded;
        next();
    });
}

// Endpoint to generate and return a JWT
app.post('/login', (req, res) => {
    const { username, password } = req.body;

    // Authenticate user (replace with your actual authentication logic)
    // For simplicity, assume any username and password combination is valid
    const user = { username, role: 'user' };

    // Generate a JWT
    const token = jwt.sign(user, secretKey, { expiresIn: '1h' });

    // Store the token in memory
    tokenStore[token] = user;

    res.json({ token });
});

// Protected endpoint that requires a valid JWT for access
app.get('/protected', verifyToken, (req, res) => {
    res.json({ message: 'This is a protected endpoint', user: req.user });
});

// Start the server
const port = 3000;
app.listen(port, () => {
    console.log(`Server is running on http://localhost:${port}`);
});

@Configuration
@EnableAuthorizationServer
public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter {

    @Autowired
    private AuthenticationManager authenticationManager;

    @Bean
    public TokenStore inMemoryTokenStore() {
        return new InMemoryTokenStore();
    }

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
        clients
            .inMemory()
            .withClient("client")
            .secret("{noop}secret")  // 使用 "{noop}" 表示不加密
            .authorizedGrantTypes("password", "authorization_code", "refresh_token")
            .scopes("read", "write")
            .accessTokenValiditySeconds(3600)
            .refreshTokenValiditySeconds(86400);
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
        endpoints
            .tokenStore(inMemoryTokenStore())
            .authenticationManager(authenticationManager);
    }
}

@Configuration
@EnableAuthorizationServer
public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter {

    @Autowired
    private AuthenticationManager authenticationManager;
    
    @Autowired
    private DataSource dataSource;

    @Bean
    public TokenStore jdbcTokenStore() {
        return new JdbcTokenStore(dataSource);
    }

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
        clients
            .jdbc(dataSource);
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
        endpoints
            .tokenStore(jdbcTokenStore())
            .authenticationManager(authenticationManager);
    }
}

@Configuration
@EnableAuthorizationServer
public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter {

    @Autowired
    private AuthenticationManager authenticationManager;

    @Value("${security.jwt.client-id}")
    private String clientId;

    @Value("${security.jwt.client-secret}")
    private String clientSecret;

    @Value("${security.jwt.grant-type}")
    private String grantType;

    @Value("${security.jwt.scope-read}")
    private String scopeRead;

    @Value("${security.jwt.scope-write}")
    private String scopeWrite;

    @Value("${security.jwt.resource-ids}")
    private String resourceIds;

    @Bean
    public TokenStore jwtTokenStore() {
        return new JwtTokenStore(jwtAccessTokenConverter());
    }

    @Bean
    public JwtAccessTokenConverter jwtAccessTokenConverter() {
        JwtAccessTokenConverter converter = new JwtAccessTokenConverter();
        converter.setSigningKey("secret");
        return converter;
    }

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
        clients
            .inMemory()
            .withClient(clientId)
            .secret("{noop}" + clientSecret)
            .authorizedGrantTypes(grantType)
            .scopes(scopeRead, scopeWrite)
            .resourceIds(resourceIds);
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
        endpoints
            .tokenStore(jwtTokenStore())
            .accessTokenConverter(jwtAccessTokenConverter())
            .authenticationManager(authenticationManager);
    }
}

@Autowired
private RedisConnectionFactory redisConnectionFactory;
/**
 * redis token 配置
 */
@Bean
public TokenStore redisTokenStore() {
    return new RedisTokenStore(redisConnectionFactory);
}


@Autowired(required = false)
private TokenStore redisTokenStore;
/**
 * 端點(diǎn)（處理入口）
 */
@Override
public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
   endpoints.tokenStore(redisTokenStore);
   ....
}