package com.changhong.epc.rely.api.tool;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.math.NumberUtils;

import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.util.Objects;
import java.util.Optional;

@Slf4j
public class CurrencyTool {

    // 美元
    public static final String USD = "USD";

    // 人民币
    public static final String RMB = "RMB";


    // 汇率转换后小数点限制
    public static final DecimalFormat CURRENCY_TYPE = new DecimalFormat("#0.00");

    /**
     * 兑换金额
     * @param exchangeRate
     * @param money
     * @return
     */
    public static String valueOf(String exchangeRate, Object money){
        return Optional.ofNullable(money)
                .map(Object::toString)
                .filter(NumberUtils::isNumber)
                .filter(m->NumberUtils.isNumber(exchangeRate))
//                .filter(m->!Objects.equals(money, "0"))
                    // 转换BigDecimal
                    .map(BigDecimal::new)
                    // 乘汇率
                    .map(decimal->decimal.multiply(new BigDecimal(exchangeRate)))
                    // 格式化保留两位小数
                    .map(CurrencyTool::format)
                // 为空返回原始金额
                .orElse(Objects.toString(money));
    }

    /**
     * 汇率单位计算
     * @param exchangeRate
     * @param number
     * @return
     */
    public static String divide(String exchangeRate, int number){
        return Optional.ofNullable(exchangeRate)
                .filter(NumberUtils::isNumber)
                    .map(BigDecimal::new)
                    .map(decimal->decimal.divide(new BigDecimal(number)))
                    .map(Object::toString)
                .orElse(exchangeRate);
    }

    public static String format(Object val){
        return CURRENCY_TYPE.format(val);
    }

    public static void main(String... args){
        System.out.println(CurrencyTool.valueOf(CurrencyTool.divide("16.2122", 100), "0"));
        System.out.println(CurrencyTool.divide("16.2122", 100));
    }
}