package com.terra.common.config;

import com.alibaba.fastjson2.JSONReader;
import com.alibaba.fastjson2.JSONWriter;
import com.alibaba.fastjson2.support.config.FastJsonConfig;
import com.alibaba.fastjson2.support.spring.http.converter.FastJsonHttpMessageConverter;

import com.terra.common.interceptor.AuthInterceptor;
import com.terra.common.service.CommonService;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.config.annotation.*;

import javax.annotation.Resource;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.List;

/**
 * WebConfig：通过实现该接口并重写方法来‌扩展‌Spring MVC配置，不会覆盖默认配置。
 */
@Configuration
public class WebConfig implements WebMvcConfigurer {
    @Resource
    CommonService commonService;

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        // 设置访问路径为 “/” 跳转到指定页面
        registry.addViewController("/").setViewName("redirect:/sign/toIndex");
        // 设置为最高优先级
        registry.setOrder(Ordered.HIGHEST_PRECEDENCE);
    }

    /**
     * 获取拦截器对象
     */
    public AuthInterceptor getAuthBean() {
        return new AuthInterceptor(commonService);
    }

    /**
     * swagger控制
     */
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
        //registry.addResourceHandler("swagger-ui.html").addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/swagger-ui/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
        registry.addResourceHandler("/druid/**").addResourceLocations("classpath:/META-INF/resources/druid/");
        registry.addResourceHandler("/**").addResourceLocations("classpath:/static/");
    }

    /**
     * 忽略url地址大小写
     */
    @Override
    public void configurePathMatch(PathMatchConfigurer configurer) {
        AntPathMatcher matcher = new AntPathMatcher();
        matcher.setCaseSensitive(false);

        configurer.setPathMatcher(matcher);
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(getAuthBean())
                //.excludePathPatterns("/v3/api-docs")
                .addPathPatterns("/**");
    }

    /**
     * 处理json格式，值null的转换为""
     */
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        //FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter();
        FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter() {
            @Override
            protected void writeInternal(Object object, org.springframework.http.HttpOutputMessage outputMessage)
                    throws IOException, org.springframework.http.converter.HttpMessageNotWritableException {
                ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
                if (attributes != null) {
                    String requestURI = attributes.getRequest().getRequestURI();
                    if ("/v3/api-docs".equals(requestURI)) { // 排除 /v3/api-docs 路径
                        // 使用默认的 JSON 序列化（如 Jackson），这里需要手动处理，不能直接调用 super.writeInternal
                        outputMessage.getBody().write(String.valueOf(object).getBytes());
                        return;
                    }
                }
                super.writeInternal(object, outputMessage); // 其他路径使用 Fastjson2 处理
            }
        };
        converter.setFastJsonConfig(getFastJsonConfig());
        converter.setDefaultCharset(StandardCharsets.UTF_8);
        converter.setSupportedMediaTypes(Collections.singletonList(
                MediaType.APPLICATION_JSON
        ));
        converters.add(0, converter);
    }

    private static FastJsonConfig getFastJsonConfig() {
        FastJsonConfig config = new FastJsonConfig();
        // 配置序列化特征
        config.setWriterFeatures(
                JSONWriter.Feature.WriteNullListAsEmpty,
                //JSONWriter.Feature.WriteNullBooleanAsFalse,
                //JSONWriter.Feature.WriteNullNumberAsZero,
                //JSONWriter.Feature.PrettyFormat, // 格式化输出
                JSONWriter.Feature.WriteMapNullValue // 输出空字段
        );
        // 反序列化特性配置
        config.setReaderFeatures(
                JSONReader.Feature.FieldBased,
                JSONReader.Feature.SupportArrayToBean
        );
        return config;
    }
}