using System;

namespace MySystem.Entity.UnionPay
{
    /// <summary>
    /// 银联请求报文
    /// </summary>
    public class UnionPayRequest<T>
    {
        private static int _sequenceNumber = 0;

        /// <summary>
        /// 服务商编号，由乐刷分配的接入方唯一标识，明文传输
        /// </summary>
        public string agentId { get; set; }

        /// <summary>
        /// 当前代理商编号（操作来源）
        /// </summary>
        public string currentAgentId { get; set; }

        /// <summary>
        /// 版本号，目前固定值1.0
        /// </summary>
        public string version { get; set; } = "1.0";

        /// <summary>
        /// 请求流水号(yyyyMMddHHmmssSSSXXXXX，其中 XXXXX为5位顺序号,禁止使用UUID等无意义数据)
        /// </summary>
        public string reqSerialNo { get; set; } = GenerateReqSerialNo();

        /// <summary>
        /// 签名串
        /// </summary>
        public string sign { get; set; }

        /// <summary>
        /// 验签方式，默认true-国密验签，false-MD5验签
        /// </summary>
        public bool algorithm { get; set; } = true;

        /// <summary>
        /// 业务数据
        /// </summary>
        public T data { get; set; }

        /// <summary>
        /// 生成请求流水号
        /// </summary>
        /// <returns>格式化的请求流水号</returns>
        private static string GenerateReqSerialNo()
        {
            // 生成当前时间戳部分：yyyyMMddHHmmssSSS
            string timestamp = DateTime.Now.ToString("yyyyMMddHHmmssfff");
            
            // 生成5位顺序号，循环递增
            int sequence = System.Threading.Interlocked.Increment(ref _sequenceNumber);
            if (sequence > 99999)
            {
                System.Threading.Interlocked.Exchange(ref _sequenceNumber, 1);
                sequence = 1;
            }
            
            // 组合完整的请求流水号
            return $"{timestamp}{sequence.ToString("D5")}";
        }
    }

    /// <summary>
    /// 银联请求报文（非泛型版本，兼容旧代码）
    /// </summary>
    public class UnionPayRequest : UnionPayRequest<object>
    {
    }
}