package com.jilongda.common.utils;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;

import java.lang.reflect.Field;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

/**
 * @author xiaochen
 * @ClassName SpringUtils
 * @Description
 * @date 2021-06-17 15:37
 */
public class SpringUtils {

    /**
     * 对象属性复制
     *
     * @param a
     * @param clazz
     * @param <A>
     * @param <B>
     * @return
     */
    public static <A, B> B beanCopy(A a, Class<B> clazz) {
        try {
            B b = clazz.newInstance();
            BeanUtils.copyProperties(a, b);
            return b;
        } catch (InstantiationException | IllegalAccessException e) {
            throw new RuntimeException("获取对象实例失败");
        }
    }

    /**
     * 对象属性复制
     *
     * @param a
     * @param a
     * @param <A>
     * @param <B>
     * @return
     */
    public static <A, B> B beanCopy(A a, B b) {
        BeanUtils.copyProperties(a, b);
        return b;
    }

    public static <A, B> B beanCopyNotNull(A a, B b) {
        BeanUtils.copyProperties(a, b, getNullPropertyNames(a));
        return b;
    }

    /**
     * 只拷贝不为null的属性
     *
     * @param source
     * @return java.lang.String[]
     * @author xiaochen
     * @date 2022-01-04 18:27
     */
    public static String[] getNullPropertyNames(Object source) {
        final BeanWrapper src = new BeanWrapperImpl(source);
        java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();

        Set<String> emptyNames = new HashSet<String>();
        for (java.beans.PropertyDescriptor pd : pds) {
            Object srcValue = src.getPropertyValue(pd.getName());
            if (srcValue == null) {
                emptyNames.add(pd.getName());
            }
        }
        String[] result = new String[emptyNames.size()];
        return emptyNames.toArray(result);
    }

    /**
     * 利用反射将map集合封装成bean对象
     *
     * @param map
     * @param clazz
     * @return
     */
    public static <T> T mapToBean(Map<String, Object> map, Class<?> clazz) throws Exception {
        Object obj = clazz.newInstance();
        if (map != null && !map.isEmpty() && map.size() > 0) {
            for (Map.Entry<String, Object> entry : map.entrySet()) {
                // 属性名
                String propertyName = entry.getKey();
                // 属性值
                Object value = entry.getValue();
                String setMethodName = "set" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
                //获取和map的key匹配的属性名称
                Field field = getClassField(clazz, propertyName);
                if (field == null) {
                    continue;
                }
                Class<?> fieldTypeClass = field.getType();
                value = convertValType(value, fieldTypeClass);
                try {
                    clazz.getMethod(setMethodName, field.getType()).invoke(obj, value);
                } catch (NoSuchMethodException e) {
                    e.printStackTrace();
                }
            }
        }
        return (T) obj;
    }

    /**
     * 根据给定对象类匹配对象中的特定字段
     *
     * @param clazz
     * @param fieldName
     * @return
     */
    private static Field getClassField(Class<?> clazz, String fieldName) {
        if (Object.class.getName().equals(clazz.getName())) {
            return null;
        }
        Field[] declaredFields = clazz.getDeclaredFields();
        for (Field field : declaredFields) {
            if (field.getName().equals(fieldName)) {
                return field;
            }
        }
        //如果该类还有父类，将父类对象中的字段也取出
        Class<?> superClass = clazz.getSuperclass();
        //递归获取
        if (superClass != null) {
            return getClassField(superClass, fieldName);
        }
        return null;
    }

    /**
     * 将map的value值转为实体类中字段类型匹配的方法
     *
     * @param value
     * @param fieldTypeClass
     * @return
     */
    private static Object convertValType(Object value, Class<?> fieldTypeClass) {
        Object retVal;
        if (Long.class.getName().equals(fieldTypeClass.getName())
                || long.class.getName().equals(fieldTypeClass.getName())) {
            retVal = Long.parseLong(value.toString());
        } else if (Integer.class.getName().equals(fieldTypeClass.getName())
                || int.class.getName().equals(fieldTypeClass.getName())) {
            retVal = Integer.parseInt(value.toString());
        } else if (Float.class.getName().equals(fieldTypeClass.getName())
                || float.class.getName().equals(fieldTypeClass.getName())) {
            retVal = Float.parseFloat(value.toString());
        } else if (Double.class.getName().equals(fieldTypeClass.getName())
                || double.class.getName().equals(fieldTypeClass.getName())) {
            retVal = Double.parseDouble(value.toString());
        } else {
            retVal = value;
        }
        return retVal;
    }
}