namespace YLErp.Modules.VolatilityModule
{
    /// <summary>
    /// 品种波动率数据服务
    /// </summary>
    public class VarietyVolService : YLBaseService
    {
        public VarietyVolService(OptUserInfo userInfo) : base(userInfo)
        {
        }

        public VarietyVolService(YLBaseService baseService) : base(baseService)
        {
        }

        /// <summary>
        /// 获取距valueDate最近的品种波动率
        /// </summary>
        public VarietyVol GetVol(long varietyId, DateTime valueDate)
        {
            var query = from volDb in DbContext.variety_vol
                        where volDb.VarietyId == varietyId
                        && volDb.ValueDate <= valueDate
                        orderby volDb.ValueDate descending
                        select volDb;
            return query.FirstOrDefault();
        }

        /// <summary>
        /// 获取距date最近的品种波动率
        /// </summary>
        public List<VarietyVolDto> GetVols(DateTime date, IEnumerable<int> varietyIds)
        {
            if (varietyIds is null)
            {
                throw new ArgumentNullException(nameof(varietyIds));
            }

            var idSet = varietyIds.ToHashSet();

            var grpQry = from vol in DbContext.variety_vol
                         where vol.ValueDate <= date && idSet.Contains(vol.VarietyId)
                         group vol by vol.VarietyId into grp
                         select new
                         {
                             VarietyId = grp.Key,
                             ValueDate = grp.Max(n => n.ValueDate)
                         };

            var qry = from gv in grpQry
                      join vol in DbContext.variety_vol on gv equals new { vol.VarietyId, vol.ValueDate }
                      orderby gv.VarietyId
                      select new VarietyVolDto
                      {
                          VarietyId = vol.VarietyId,
                          ValueDate = vol.ValueDate,
                          Vol = vol.Vol
                      };

            var list = qry.ToList();

            foreach (var data in list)
            {
                idSet.Remove(data.VarietyId);
            }

            var defArr = idSet.Select(n => new VarietyVolDto { VarietyId = n, ValueDate = date, Vol = ConsGlobal.DefaultVol }).ToArray();

            list.AddRange(defArr);

            return list;
        }

        /// <summary>
        /// 保存数据
        /// </summary>
        public void SaveData(int varietyId, DateTime valueDate, double vol)
        {
            if (varietyId == default)
            {
                throw new ArgumentNullException("varietyId");
            }

            if (valueDate == default)
            {
                throw new ArgumentNullException("valueDate");
            }

            if (vol == default(int))
            {
                throw new ArgumentNullException("vol");
            }

            if (!DbContext.variety.Any(n => n.id == varietyId))
            {
                throw new ServiceException("品种不存在");
            }

            var dbModel = DbContext.variety_vol.FirstOrDefault(n => n.VarietyId == varietyId && n.ValueDate == valueDate);

            if (dbModel == null)
            {
                DbContext.variety_vol.Add(new VarietyVol
                {
                    ValueDate = valueDate,
                    VarietyId = varietyId,
                    Vol = vol,
                    OptDate = DateTime.Now,
                    OptId = UserId,
                    OptName = UserName
                });
            }
            else
            {
                dbModel.Vol = vol;
                dbModel.OptId = UserId;
                dbModel.OptName = UserName;
                dbModel.OptDate = OptDate;
            }

            DbContext.SaveChanges();
        }

        /// <summary>
        /// 
        /// </summary>
        public Dictionary<int, double> GetVols(DateTime date, IEnumerable<trade> tradeList)
        {
            var result = new Dictionary<int, double>();
            var codes = tradeList.Select(O => O.UnderlyingCode).ToHashSet(StringComparer.OrdinalIgnoreCase);

            var varietyMap = DbContext.underlying_manager
                .Where(underlyingDb => codes.Contains(underlyingDb.UnderlyingCode))
                .ToDictionary(K => K.UnderlyingCode, V => V.UnderlyingTypeId, StringComparer.OrdinalIgnoreCase);

            var vols = GetVols(date, varietyMap.Values);

            foreach (var t in tradeList)
            {
                if (varietyMap.TryGetValue(t.UnderlyingCode, out var vid))
                {
                    result[t.id] = vols.Find(O => O.VarietyId == vid).Vol;
                }
                else
                {
                    throw new Exception($"标的'{t.UnderlyingCode}'找不到光证波动率,因未关联品种");
                }
            }
            return result;
        }

        /// <summary>
        /// 
        /// </summary>
        public static double? GetVarietyVol(DateTime valueDate, int varietyId)
        {
            using (var db = DbContextFactory.GetYLDbContext())
            {
                var query = from v in db.variety_vol
                            where v.VarietyId == varietyId && v.ValueDate <= valueDate
                            orderby v.ValueDate descending
                            select (double?)v.Vol;
                return query.FirstOrDefault();
            }
        }

        /// <summary>
        /// 
        /// </summary>
        public static double? GetVarietyVol(DateTime valueDate, string underlyingCode)
        {
            if (string.IsNullOrWhiteSpace(underlyingCode))
            {
                return null;
            }

            using (var db = DbContextFactory.GetYLDbContext())
            {
                var query = from un in db.underlying_manager.Where(n => n.UnderlyingCode == underlyingCode)
                            join v in db.variety_vol on un.UnderlyingTypeId equals v.VarietyId
                            where v.ValueDate <= valueDate
                            orderby v.ValueDate descending
                            select (double?)v.Vol;
                return query.FirstOrDefault();
            }
        }
    }
}