package com.zcxk.common;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;

import java.text.SimpleDateFormat;

/**
 * Jackson实现对象和json字符串之间的转换
 * Created by lin
 */
@Slf4j
public class JacksonUtil {

    private static ObjectMapper objectMapper = new ObjectMapper();

    static {
        //对象的所有字段全部列入
        objectMapper.setSerializationInclusion(JsonInclude.Include.ALWAYS);

        //取消默认转换timestamps形式
        objectMapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);

        //忽略空Bean转json的错误
        objectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);

        //所有的日期格式都统一为以下的样式，即yyyy-MM-dd HH:mm:ss
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));

        //忽略 在json字符串中存在，但是在java对象中不存在对应属性的情况。防止错误
        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
    }


    public static <T> String obj2String(T obj) {
        if (obj == null) {
            return null;
        }
        try {
            return obj instanceof String ? (String) obj : objectMapper.writeValueAsString(obj);
        } catch (Exception e) {
            log.warn("Parse Object to String error", e);
            return null;
        }
    }

    public static <T> String obj2StringPretty(T obj) {
        if (obj == null) {
            return null;
        }
        try {
            return obj instanceof String ? (String) obj : objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj);
        } catch (Exception e) {
            log.warn("Parse Object to String error", e);
            return null;
        }
    }


    public static <T> T string2Obj(String str, Class<T> clazz) {
        if (StringUtils.isEmpty(str) || clazz == null) {
            return null;
        }

        try {
            return clazz.equals(String.class) ? (T) str : objectMapper.readValue(str, clazz);
        } catch (Exception e) {
            log.warn("Parse String to Object error", e);
            return null;
        }
    }


    public static <T> T string2Obj(String str, TypeReference<T> typeReference) {
        if (StringUtils.isEmpty(str) || typeReference == null) {
            return null;
        }
        try {
            return (T) (typeReference.getType().equals(String.class) ? str : objectMapper.readValue(str, typeReference));
        } catch (Exception e) {
            log.warn("Parse String to Object error", e);
            return null;
        }
    }


    public static <T> T string2Obj(String str, Class<?> collectionClass, Class<?>... elementClasses) {
        JavaType javaType = objectMapper.getTypeFactory().constructParametricType(collectionClass, elementClasses);
        try {
            return objectMapper.readValue(str, javaType);
        } catch (Exception e) {
            log.warn("Parse String to Object error", e);
            return null;
        }
    }
}

