package com.macro.mall.tiny.config;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.*;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spi.service.contexts.SecurityContext;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.spring.web.plugins.WebFluxRequestHandlerProvider;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @auther macrozheng
 * @description Swagger文档的相关配置（带认证）
 * @date 2022/11/22
 * @github https://github.com/macrozheng
 */
@Configuration
public class Swagger2Config {
    @Bean
    public Docket createRestApi() {
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo())
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.macro.mall.tiny.controller"))
                .paths(PathSelectors.any())
                .build()
                //添加登录认证
                .securitySchemes(securitySchemes())
                .securityContexts(securityContexts());
    }

    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("SwaggerUI演示")
                .description("mall-tiny")
                .contact(new Contact("macro", null, null))
                .version("1.0")
                .build();
    }

    private List<SecurityScheme> securitySchemes() {
        //设置请求头信息
        List<SecurityScheme> result = new ArrayList<>();
        ApiKey apiKey = new ApiKey("Authorization", "Authorization", "header");
        result.add(apiKey);
        return result;
    }

    private List<SecurityContext> securityContexts() {
        //设置需要登录认证的路径
        List<SecurityContext> result = new ArrayList<>();
        result.add(getContextByPath("/brand/.*"));
        return result;
    }

    private SecurityContext getContextByPath(String pathRegex) {
        return SecurityContext.builder()
                .securityReferences(defaultAuth())
                .forPaths(PathSelectors.regex(pathRegex))
                .build();
    }

    private List<SecurityReference> defaultAuth() {
        List<SecurityReference> result = new ArrayList<>();
        AuthorizationScope authorizationScope = new AuthorizationScope("global", "accessEverything");
        AuthorizationScope[] authorizationScopes = new AuthorizationScope[1];
        authorizationScopes[0] = authorizationScope;
        result.add(new SecurityReference("Authorization", authorizationScopes));
        return result;
    }

    @Bean
    public BeanPostProcessor generateBeanPostProcessor(){
        return new BeanPostProcessor() {

            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof WebMvcRequestHandlerProvider || bean instanceof WebFluxRequestHandlerProvider) {
                    customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
                }
                return bean;
            }

            private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {
                List<T> copy = mappings.stream()
                        .filter(mapping -> mapping.getPatternParser() == null)
                        .collect(Collectors.toList());
                mappings.clear();
                mappings.addAll(copy);
            }

            @SuppressWarnings("unchecked")
            private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
                try {
                    Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
                    field.setAccessible(true);
                    return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    throw new IllegalStateException(e);
                }
            }
        };
    }
}
