package com.moral.api.util;

import com.moral.anno.FieldName;
import com.moral.pojo.CompareFieldResult;
import lombok.extern.slf4j.Slf4j;

import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

/**
 * @ClassName ComparePropertyUtils
 * @Description TODO
 * @Author 陈凯裕
 * @Date 2021/8/24 13:34
 * @Version TODO
 **/
@Slf4j
public class CompareFieldUtils {

    /**
    * @Description: 对比两个对象之间属性的区别
            * @Param: [t, oldObject, newObject]
            * @return: java.util.List<com.moral.pojo.CompareFieldResult>
            * @Author: 陈凯裕
            * @Date: 2021/8/24
            */
    public static <T> List<CompareFieldResult> compare(T t, Object oldObject, Object newObject) {
        List<CompareFieldResult> results = new ArrayList<>();
        try {
            T oldObj = (T) oldObject;
            T newObj = (T) newObject;
            //获取class对象
            Class<?> TClass = oldObject.getClass();
            //获取类的属性
            Field[] fields = TClass.getDeclaredFields();
            for (Field field : fields) {
                //过滤序列化信息Id
                if ("serialVersionUID".equals(field.getName())) {
                    continue;
                }
                //如果没有fieldName注解则跳过
                FieldName annotation = field.getAnnotation(FieldName.class);
                if(annotation==null)
                    continue;
                //创建属性扫描器
                PropertyDescriptor pd = new PropertyDescriptor(field.getName(), TClass);
                //获取该属性的get方法
                Method readMethod = pd.getReadMethod();
                //读取对象该属性的值
                Object oldDataObj = readMethod.invoke(oldObj);
                Object newDataObj = readMethod.invoke(newObj);
                //如果新的值为null则证明该属性没有更新
                if(newDataObj==null)
                    continue;
                //如果旧值和新值相等则证明没有改变
                if(oldDataObj!=null&&oldDataObj.toString().equals(newDataObj.toString()))
                    continue;
                //创建返回对象
                CompareFieldResult result = new CompareFieldResult();
                result.setFieldName(field.getName());
                result.setFieldAnnoName(annotation.value());

                if(newDataObj.equals(""))
                    result.setNewData("null");
                else
                    result.setNewData(newDataObj.toString());

                if(oldDataObj==null||oldDataObj.equals(""))
                    result.setOldData("null");
                else
                    result.setOldData(oldDataObj.toString());

                results.add(result);
            }
        }catch (IntrospectionException e) {
            log.error(e.getMessage());
        } catch (IllegalAccessException e) {
            log.error(e.getMessage());
        } catch (InvocationTargetException e) {
            log.error(e.getMessage());
        }
        return results;
    }

    /**
    * @Description: 将对比结果类转换为content
            * @Param: [results, content] content参数需要传入修改的基本描述。比如，修改了前台菜单，修改了后台角色
            * @return: java.lang.String
            * @Author: 陈凯裕
            * @Date: 2021/8/24
            */
    public static String resultsConvertContent(List<CompareFieldResult> results,String content){
        StringBuilder contentReulst = new StringBuilder(content+";");
        for (CompareFieldResult result : results) {
            contentReulst.append(result.getFieldAnnoName()+"："+result.getOldData()+"->"+result.getNewData()+";");
        }
        return contentReulst.toString();
    }
}