namespace DS.Module.Core;

/// <summary>
/// Decimal 工具类
/// </summary>
public static class DecimalUtil
{
    /// <summary>
    /// 获得decimal的精度
    /// </summary>
    /// <param name="value"></param>
    /// <returns></returns>
    public static int Precise(this decimal value)
    {
        var s = value.ToString();

        if (!s.Contains('.'))
        {
            return 0;
        }

        return s.Length - s.IndexOf('.') - 1;
    }

    /// <summary>
    /// 检查金额, 最大值为8位数字
    /// </summary>
    /// <param name="money">金额</param>
    /// <param name="title">标题</param>
    /// <param name="ignoreMax">是否忽略最大值检查 默认为否</param>
    /// <param name="digit">小数位数</param>
    /// <returns></returns>
    public static (bool isSuccess, string errMsg) CheckMoney(this decimal money, string title, bool ignoreMax = false,
        int maxDigit = 8, int digit = 3)
    {
        // 0或者负数检查
        if (money <= 0M)
        {
            return (false, $"{title}不为0或负");
        }

        // 最大值检查
        if (!ignoreMax)
        {
            decimal maximum = NumberConst.MAX_8;
            switch (maxDigit)
            {
                case 5:
                    maximum = NumberConst.MAX_5;
                    break;

                default:
                    maximum = NumberConst.MAX_8;
                    break;
            }

            if (money > maximum)
            {
                return (false, $"{title}不能超过最大值");
            }
        }

        // 两位有效小数检查
        int precise = money.Precise();
        if (precise > digit)
        {
            return (false, $"{title}位数超出范围");
            //return (false, $"{title}最多有两位小数");
        }

        return (true, string.Empty);
    }
}