package com.rzyc.provinceUtil;


import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;

/**
 * @author dong
 * @date 2025-03-18 15:25
 * @Version V1.0
 */
public class JsonUtils {


    private static final ObjectMapper objectMapper = new ObjectMapper();

    /**
     * 将 JSON 字符串转换为包含泛型的对象
     * @param json      JSON 字符串
     * @param mainClass 主类型（如 Result.class）
     * @param subClass  泛型参数类型（如 User.class）
     * @return 转换后的对象
     */
    public static <T, R> T fromJson(String json, Class<T> mainClass, Class<R> subClass) {
        try {
            // 动态构建泛型类型（例如 Result<User>）
            Type type = createParametricType(mainClass, subClass);
            return objectMapper.readValue(json, new TypeReference<T>() {
                @Override
                public Type getType() {
                    return type;
                }
            });
        } catch (Exception e) {
            throw new RuntimeException("JSON 转换失败", e);
        }
    }




    /**
     * 构建 ParameterizedType（例如 Result<User>）
     */
    private static ParameterizedType createParametricType(final Class<?> rawType,
                                                          final Type... typeArguments){
        return new ParameterizedType() {
            @Override
            public Type[] getActualTypeArguments() {
                return typeArguments;
            }

            @Override
            public Type getRawType() {
                return rawType;
            }

            @Override
            public Type getOwnerType() {
                return null;
            }
        };
    }

    /**
     * 使用示例：解析 Result<List<User>>
     * @version v1.0
     * @author dong
     * @date 2025/3/18 15:44
     */
/*    Type userListType = new TypeToken<List<User>>() {}.getType();
    Result<List<User>> result = JsonUtils.fromJsonComplex(
            json,
            Result.class,
            userListType
    );*/

    /**
     * json转list
     * @version v1.0
     * @author dong
     * @date 2025/3/18 15:43
     */
    public static <T> T fromJsonComplex(String json, Class<?> rawType, Type... genericTypes) {
        try {
            ParameterizedType type = new ParameterizedType() {
                @Override
                public Type[] getActualTypeArguments() {
                    return genericTypes;
                }

                @Override
                public Type getRawType() {
                    return rawType;
                }

                @Override
                public Type getOwnerType() {
                    return null;
                }
            };
            return objectMapper.readValue(json, new TypeReference<T>() {
                @Override
                public Type getType() {
                    return type;
                }
            });
        } catch (Exception e) {
            throw new RuntimeException("JSON 转换失败", e);
        }
    }


}