ChouBox/ChouBox.Code/Other/SMSBLL.cs

using AutoMapper;

using ChouBox.Code.AppExtend;
using ChouBox.Code.TencentCloudExtend;
using ChouBox.Model.Entities;

using HuanMeng.DotNetCore.Base;

using Microsoft.Extensions.Logging;

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ChouBox.Code.Other;

/// <summary>
/// 发送验证码服务
/// </summary>
public class SMSBLL : ChouBoxCodeBase
{
    private const string RETRY_COUNT_SUFFIX = ":RetryCount";
    private const string LOCK_SUFFIX = ":Lock";

    public SMSBLL(IServiceProvider serviceProvider) : base(serviceProvider)
    {
    }

    /// <summary>
    /// 发送验证码
    /// </summary>
    /// <param name="phone"></param>
    /// <param name="codeType">验证码类型：1-注册，2-登录，3-找回密码，4-修改手机，5-修改邮箱，6-其他</param>
    /// <param name="userId">用户ID，可为空表示未登录用户</param>
    /// <returns>返回下一次可请求的等待秒数，-1表示当天不能再请求</returns>
    /// <exception cref="CustomException"></exception>
    /// <exception cref="Exception"></exception>
    public async Task<int> SendPhoneAsync(string phone, sbyte codeType = 2, ulong? userId = null)
    {
        if (string.IsNullOrEmpty(phone))
        {
            throw new ArgumentNullException("手机号不能为空");
        }
        var smsConfig = await this.GetTencentSMSConfigAsync();
        if (smsConfig == null)
        {
            throw new ArgumentNullException("暂未开放发送验证码!");
        }

        // 检查当天发送次数限制
        var dailyCountKey = $"VerificationCodeDailyCount:{phone}:{DateTime.Now:yyyyMMdd}";
        var dailyCount = RedisCache.StringGet<int?>(dailyCountKey) ?? 0;

        // 获取重试次数
        var retryCountKey = $"VerificationCode:{phone}{RETRY_COUNT_SUFFIX}";
        var retryCount = RedisCache.StringGet<int?>(retryCountKey) ?? 0;
        var resendLockKey = $"VerificationCode:{phone}{LOCK_SUFFIX}";
        var resendLock = RedisCache.StringGet<string>(resendLockKey);

        // 计算本次等待时间
        int waitSeconds = GetWaitSeconds(retryCount);

        if (resendLock != null && !string.IsNullOrEmpty(resendLock))
        {
            // 获取锁的剩余过期时间（秒）
            var remainingSeconds = RedisCache.KeyTimeToLive(resendLockKey)?.TotalSeconds ?? 0;
            remainingSeconds = Math.Ceiling(remainingSeconds); // 向上取整

            string message;
            if (remainingSeconds <= 60)
            {
                message = $"验证码发送过于频繁，请{remainingSeconds}秒后再试。";
            }
            else
            {
                int remainingMinutes = (int)Math.Floor(remainingSeconds / 60);
                message = $"验证码发送过于频繁，请{remainingMinutes}分钟后再试。";
            }

            throw new CustomException(message);
        }

        // 设置每天最大发送次数为5次
        const int maxDailyCount = 5;
        if (dailyCount >= maxDailyCount)
        {
            // 记录达到每日上限日志
            Logger.LogWarning($"手机号{phone}当天验证码发送次数已达上限({maxDailyCount}次)");
            throw new CustomException($"当天验证码发送次数已达上限，请明天再试");
        }

        Random random = new Random();
        var verificationCode = random.Next(1000, 9999);
        var redisKey = $"VerificationCode:{phone}";

        // 获取客户端真实IP地址
        string ipAddress = GetRealIpAddress();

        try
        {
            TencentSMSSendVerificationCode tencentSMSSendVerificationCode = new TencentSMSSendVerificationCode(smsConfig, phone);
            bool smsSucceeded = true;
            string errorMessage = "验证码发送失败";
            
            try
            {
                var result = await tencentSMSSendVerificationCode.SendVerificationCode(verificationCode.ToString(), 5);
                if (!result)
                {
                    smsSucceeded = false;
                }
            }
            catch (Exception smsEx)
            {
                smsSucceeded = false;
                errorMessage = smsEx.Message;
                // 记录发送失败日志
                Logger.LogError($"验证码发送异常，手机号：{phone}，IP：{ipAddress}，错误：{smsEx.Message}");
            }

            // 无论成功失败都更新重试次数和锁定时间
            retryCount++;
            var nextWaitSeconds = GetWaitSeconds(retryCount);

            // 设置不能重发的锁
            await RedisCache.StringSetAsync(resendLockKey, "1", TimeSpan.FromSeconds(waitSeconds));

            // 更新重试次数，5分钟后过期
            await RedisCache.StringSetAsync(retryCountKey, retryCount.ToString(), TimeSpan.FromMinutes(5));

            // 更新当天发送次数计数并设置过期时间为当天剩余时间
            dailyCount++;
            var endOfDay = DateTime.Today.AddDays(1).AddSeconds(-1); // 当天23:59:59
            var expireTime = endOfDay - DateTime.Now;
            await RedisCache.StringSetAsync(dailyCountKey, dailyCount.ToString(), expireTime);

            // 如果短信发送失败，抛出异常
            if (!smsSucceeded)
            {
                throw new CustomException(errorMessage);
            }

            // 发送成功，存入Redis，5分钟有效期
            await RedisCache.StringSetAsync(redisKey, verificationCode.ToString(), TimeSpan.FromMinutes(5));

            // 保存到数据库
            var verificationRecord = new UserVerificationCodes
            {
                UserId = userId,
                Account = phone,
                Code = verificationCode.ToString(),
                CodeType = codeType,
                Channel = "sms",
                IpAddress = ipAddress,
                Status = 0, // 未使用
                CreatedAt = DateTime.Now,
                UpdatedAt = DateTime.Now,
                ExpiredAt = DateTime.Now.AddMinutes(5)
            };

            await Dao.Context.UserVerificationCodes.AddAsync(verificationRecord);
            await Dao.Context.SaveChangesAsync();

            return nextWaitSeconds;
        }
        catch (Exception ex)
        {
            // 记录异常日志
            Logger.LogError($"发送验证码异常：{ex.Message}，手机号：{phone}，IP：{ipAddress}");
            throw;
        }
    }

    /// <summary>
    /// 根据重试次数获取等待时间
    /// </summary>
    /// <param name="retryCount">重试次数</param>
    /// <returns>等待秒数，-1表示不允许再次请求</returns>
    private int GetWaitSeconds(int retryCount)
    {
        return retryCount switch
        {
            0 => 30,   // 第1次请求后等待30秒
            1 => 60,   // 第2次请求后等待60秒
            2 => 60,   // 第3次请求后等待60秒
            3 => 300,  // 第4次请求后等待300秒（5分钟）
            4 => 300,  // 第5次请求后等待300秒（5分钟）
            _ => -1    // 超过5次则不允许再次请求
        };
    }
}