using YieldChain.Helpers;
using YLErp.BLL;
using YLErp.DBModels;
using YLErp.Modules;

namespace YLErp.CustomizedBizLogic
{
    /// <summary>
    /// 国联证券业务逻辑
    /// </summary>
    public class BizLogicGuoLian : BizLogicDefault
    {
        /// <summary>
        /// 在交易确认前生成交易编号
        /// 格式：GL-{yyyyMMdd}-{序号}
        /// </summary>
        public override string GenerateTradeNumberBeforeConfirm(TradeNumberReqModel reqModel, YLContext db)
        {
            if (reqModel is null)
            {
                throw new ArgumentNullException(nameof(reqModel));
            }

            // 对于对冲交易、场内交易等没有设置客户的
            if (reqModel.clientId == 0)
            {
                return DateTime.Now.ToString("yyyyMMddHHmmssfff");
            }

            // 国联格式：GLMS-{yyyyMMdd}-{4位序号}
            var leftPart = $"GLMS-{reqModel.trade.TradeDate:yyyyMMdd}-";
            var fullSize = leftPart.Length + 4;

            // 获取数据库该用户最大的交易编号记录
            var tradeNumber = db.trade.Where(x =>
                    x.TradeNumber.StartsWith(leftPart) &&
                    x.TradeNumber.Length == fullSize &&
                    x.ValidState != ConsGlobal.InValid)
                .OrderByDescending(x => x.TradeNumber)
                .Select(n => n.TradeNumber)
                .FirstOrDefault() ?? string.Empty;

            if (reqModel.importTrades != null && reqModel.importTrades.Any())
            {
                // 获取导入交易中该客户最大的交易编号记录
                var importTradeNumber = reqModel.importTrades
                    .Where(x => x.TradeNumber.StartsWith(leftPart) && x.TradeNumber.Length == fullSize)
                    .OrderByDescending(x => x.TradeNumber)
                    .Select(n => n.TradeNumber)
                    .FirstOrDefault() ?? string.Empty;
                tradeNumber = tradeNumber.CompareTo(importTradeNumber) > 0 ? tradeNumber : importTradeNumber;
            }

            // 获取总的该用户最大的交易编号记录
            int startNumber = string.IsNullOrWhiteSpace(tradeNumber)
                ? 1
                : (int.Parse(tradeNumber.Substring(leftPart.Length)) + 1);

            return GetTradeNumber(startNumber, leftPart, db);
        }

        /// <summary>
        /// 获取可用的交易编号（循环实现，避免递归栈溢出）
        /// </summary>
        private string GetTradeNumber(int startNumber, string leftPart, YLContext db)
        {
            for (int newNumber = startNumber; newNumber < 10000; newNumber++)
            {
                var candidate = leftPart + newNumber.ToString("D4");
                var childTradeNumberPart = candidate + "-";

                // 检查是否存在以该编号开头的子交易
                bool exists = db.trade.Any(x =>
                    EF.Functions.Like(x.TradeNumber, $"{childTradeNumberPart}%") &&
                    x.ValidState != ConsGlobal.InValid);

                if (!exists)
                {
                    return candidate;
                }
            }

            throw new Exception("该客户交易编号已达到最大限制9999，生成交易编号失败");
        }

        /// <summary>
        /// 获取交易确认书前缀
        /// </summary>
        public override string GetTradeContractPrefix(string tradeNumber)
        {
            // 国联证券确认书前缀
            return "GL-";
        }

        /// <summary>
        /// 生成客户编号
        /// 格式：{年份后两位}{3位序号}{拼音首字母}
        /// </summary>
        public override void GenerateClientCode(Client clientObj, IQueryable<Client> clientDbQuery)
        {
            if (string.IsNullOrWhiteSpace(clientObj.Number))
            {
                var firstPY = PingYinHelper.GetFirstPinYin_Enhance(clientObj.Name);
                var year = DateTime.Now.ToString("yy");
                var result = "";
                lock (_clientCodeLock)
                {
                    var existingClientCodes = clientDbQuery
                        .Where(x => x.Number.StartsWith(year))
                        .Select(x => x.Number)
                        .ToList();
                    var number = existingClientCodes.Count();
                    do
                    {
                        number++;
                        result = year + number.ToString("000");
                    } while (existingClientCodes.Any(O => O.StartsWith(result)));

                    clientObj.Number = result + firstPY;
                }
            }
        }
    }
}