package com.example.demo.config;

import com.example.demo.exception.CustomAuthenticationEntryPoint;
import lombok.Getter;
import lombok.Setter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.authentication.AuthenticationServiceException;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.oauth2.jwt.Jwt;
import org.springframework.security.oauth2.jwt.JwtDecoder;
import org.springframework.security.oauth2.jwt.NimbusJwtDecoder;
import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationConverter;
import org.springframework.security.web.SecurityFilterChain;

import java.util.*;

@Configuration
@EnableWebSecurity
public class SecurityConfig {
    @Getter
    @Setter
    private CustomAuthenticationEntryPoint customAuthenticationEntryPoint;

    @Autowired
    public SecurityConfig(CustomAuthenticationEntryPoint customAuthenticationEntryPoint) {
        this.customAuthenticationEntryPoint = customAuthenticationEntryPoint;
    }


    private static final String[] WHITE_LIST = {"/swagger-ui/**", "/v3/api-docs/**", "/swagger/**"};

//    @Value("${spring.security.oauth2.resourceserver.jwt.issuer-uri}")
//    String issuerUri;

    @Value("${spring.security.oauth2.resourceserver.jwt.jwk-set-uri}")
    private String jwkSetUri;

    String jwtTokenType = "id_token";

    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http.exceptionHandling(
                        exception -> exception.authenticationEntryPoint(customAuthenticationEntryPoint))
                .authorizeHttpRequests(authorizeRequests ->
                        authorizeRequests.requestMatchers(WHITE_LIST).permitAll().anyRequest().authenticated()
                )
                .sessionManagement(sessionManagement ->
                        sessionManagement.sessionCreationPolicy(SessionCreationPolicy.STATELESS)
                )
                .csrf(AbstractHttpConfigurer::disable)
                .cors(AbstractHttpConfigurer::disable)
                .oauth2ResourceServer(oauth2ResourceServerConfigurer ->
                        oauth2ResourceServerConfigurer.jwt(jwtConfigurer -> {
                            jwtConfigurer.decoder(customJwtDecoder());
                            jwtConfigurer.jwtAuthenticationConverter(jwtAuthenticationConverter());
                        })
                );
        ;

        return http.build();
    }

     @Bean
    public JwtDecoder customJwtDecoder() {
        // 使用NimbusJwtDecoder从JWKS URL读取密钥
        return NimbusJwtDecoder.withJwkSetUri(jwkSetUri).jwtProcessorCustomizer(jwtProcessor -> {
            jwtProcessor.setJWETypeVerifier((header, context) -> {
                if (!header.getType().equals(jwtTokenType)) {
                    throw new AuthenticationServiceException("Invalid token type: " + header.getType());
                }
            });

            jwtProcessor.setJWSTypeVerifier((joseObjectType, securityContext) -> {
                if (!joseObjectType.getType().equals(jwtTokenType)) {
                    throw new AuthenticationServiceException("Invalid token type: " + joseObjectType);
                }
            });
        }).build();
    }

    @Bean
    public JwtAuthenticationConverter jwtAuthenticationConverter() {
        JwtAuthenticationConverter converter = new JwtAuthenticationConverter();
        // 提取权限
        converter.setJwtGrantedAuthoritiesConverter(this::extractAuthoritiesFromJwt);
        return converter;
    }

    private Collection<GrantedAuthority> extractAuthoritiesFromJwt(Jwt jwt) {
        // 从JWT的claims中提取角色和权限信息
        Map<String, Object> claims = jwt.getClaims();
        List<GrantedAuthority> authorities = new ArrayList<>();

        // 提取角色
        if (claims.containsKey("roles") && claims.get("roles") instanceof List) {
            List<String> roles = (List<String>) claims.get("roles");
            authorities.addAll(roles.stream()
                    .map(role -> new SimpleGrantedAuthority("ROLE_" + role))
                    .toList());
        }

        // 提取权限
        if (claims.containsKey("permissions") && claims.get("permissions") instanceof List) {
            List<String> permissions = (List<String>) claims.get("permissions");
            authorities.addAll(permissions.stream()
                    .map(SimpleGrantedAuthority::new)
                    .toList());
        }

        return authorities;
    }


//
//    @Bean
//    public JwtDecoder customJwtDecoder() {
//        return token -> {
//            try {
//                // 使用Nimbus库解析JWT
//                JWT jwt = JWTParser.parse(token);
//                String typ = jwt.getHeader().getType().toString();
//                // 检查JWT的typ是否为id_token
//                if (!typ.equals(jwtTokenType)) {
//                    throw new AuthenticationServiceException("Invalid token type: " + typ);
//                }
//
//                JWTClaimsSet claims = jwt.getJWTClaimsSet();
//
////                Date exp = claims.getExpirationTime();
////                Date now = new Date();
//                // 检测是否过期
//                if (claims.getExpirationTime().before(new Date())) {
//                    throw new AuthenticationServiceException("Token has expired");
//                }
//
//                // 将JWT转换为Spring Security的Jwt对象
//                return new Jwt(token, jwt.getJWTClaimsSet().getIssueTime().toInstant(), jwt.getJWTClaimsSet().getExpirationTime().toInstant(), jwt.getHeader().toJSONObject(), jwt.getJWTClaimsSet().toJSONObject());
//            } catch (AuthenticationServiceException | ParseException e) {
//                // 401 了
//                throw new AuthenticationServiceException(e.getMessage());
//            }
//        };
//
//
//    }
//
//    @Bean
//    public JwtAuthenticationConverter jwtAuthenticationConverter() {
//        JwtAuthenticationConverter converter = new JwtAuthenticationConverter();
//        // 提取权限
//        converter.setJwtGrantedAuthoritiesConverter(this::extractAuthoritiesFromJwt);
//
//        return converter;
//    }
//
//
//    private Collection<GrantedAuthority> extractAuthoritiesFromJwt(Jwt jwt) {
//        // 从JWT的claims中提取角色和权限信息
//        Map<String, Object> claims = jwt.getClaims();
//        List<GrantedAuthority> authorities = new ArrayList<>();
//
//        // 提取角色
//        if (claims.containsKey("roles") && claims.get("roles") instanceof List) {
//            List<String> roles = (List<String>) claims.get("roles");
//            authorities.addAll(roles.stream()
//                    .map(role -> new SimpleGrantedAuthority("ROLE_" + role))
//                    .toList());
//        }
//
//        // 提取权限
//        if (claims.containsKey("permissions") && claims.get("permissions") instanceof List) {
//            List<String> permissions = (List<String>) claims.get("permissions");
//            authorities.addAll(permissions.stream()
//                    .map(SimpleGrantedAuthority::new)
//                    .toList());
//        }
//
//        return authorities;
//    }

}