using System.Linq.Expressions;
using YLErp.BLL;
using YLErp.Modules.DataProviderModule;
using YLErp.QdpModule;

namespace YLErp.Modules.EodModule
{
    /// <summary>
    /// 日终结算服务
    /// </summary>
    public class EodSettlementService : YLBaseService
    {
        public EodSettlementService(YLBaseService baseService) : base(baseService)
        {
        }

        public EodSettlementService(OptUserInfo userInfo) : base(userInfo)
        {
        }

        public EodSettlementService(OptUserInfo userInfo, YLContext dbContext) : base(userInfo, dbContext)
        {
        }

        /// <summary>
        /// 获取日终持仓数据
        /// </summary>
        public IEnumerable<T> GetEodTradePosition<T>(DateTime settleDate, Expression<Func<T, bool>> predicate = null)
            where T : EodTradePosition
        {
            var bodDate = QdpCalendarHelper.GetNonHoliday(settleDate.AddDays(1));

            if (predicate == null)
            {
                predicate = PredicateBuilder.Create<T>(n => n.ValueDate == settleDate);
            }
            else
            {
                predicate = PredicateBuilder.Create<T>(n => n.ValueDate == settleDate).And(predicate);
            }

            // 除权数据不在这里做 SQL 左连接：同一标的一天只允许一条有效除权记录，
            // 但历史脏数据可能存在重复行。左连接会把一条 EOD 持仓扩成多行，进而重复
            // 参与后续风险/结算计算。先取得 EOD+BOD 的唯一持仓结果，再按标的代码匹配
            // 除权记录，可以把重复业务键暴露为 ToDictionary 异常，而不是静默扩行。
            var query = from eod in DbContext.Set<T>().Where(predicate)
                        join bod in DbContext.BodTradePosition.Where(n => n.ValueDate == bodDate)
                        on new { eod.BookId, eod.TradeType, eod.PositionType, eod.UnderlyingCode, ExchangeOptionCode = eod.ExchangeOptionCode ?? string.Empty }
                        equals new { bod.BookId, bod.TradeType, bod.PositionType, bod.UnderlyingCode, ExchangeOptionCode = bod.ExchangeOptionCode ?? string.Empty } into t_bod
                        from bod in t_bod.DefaultIfEmpty()
                        select new
                        {
                            eod,
                            bod = bod == null ? null : new
                            {
                                bod.Amount,
                                bod.Cost,
                                //bod.AveragePrice
                            }
                        };

            var datas = query.ToArray();
            var diviService = new TradeModule.DealModule.DividendService(OptUser);
            // 除权查询集中复用 DividendService 的有效记录条件。字典使用不区分大小写的
            // UnderlyingCode 匹配，兼容 EOD 与除权表代码大小写差异；如果同日同代码仍有
            // 多条有效记录，ToDictionary 会失败，提示迁移/结算前先清理重复数据。
            var dividendDict = diviService.GetExDividendQuery(settleDate)
                .ToDictionary(O => O.UnderlyingCode, O => O, StringComparer.OrdinalIgnoreCase);
            var eodPriceProvider = new EodPriceProvider(settleDate);
            return datas.Select(data =>
            {
                var eod = data.eod;
                var bod = data.bod;
                // 命中除权数据后仍沿用原有股票结算分支：只重算除权后的收盘价和数量，
                // 并保留原 Pv 的正负方向。其他 TradeType 当前不进入该分支，避免扩大
                // 本次查询重构的业务范围。
                if (dividendDict.TryGetValue(eod.UnderlyingCode, out var dividend))
                {
                    if (data.eod.TradeType == "股票")
                    {
                        var SettlePrice = eodPriceProvider.GetPrice(data.eod.UnderlyingCode, SettlementTypeEnum.ClosePrice);
                        SettlePrice = diviService.GetPrice(SettlePrice, dividend);
                        var amount = diviService.GetPositionAmount(data.eod.Amount, dividend);
                        eod.Pv = eod.Pv > 0 ? Math.Abs(amount * SettlePrice) : -Math.Abs(amount * SettlePrice);
                    }
                }
                if (bod != null)
                {
                    eod.Amount = bod.Amount;
                    //eod.AveragePrice = bod.AveragePrice;
                    eod.Cost = bod.Cost;
                }
                return eod;
            }).ToArray();
        }

        /// <summary>
        /// 获取日终持仓数据
        /// </summary>
        public IEnumerable<EodTradePositionAndRisk> GetEodTradePosition<TPos, TRisk>(DateTime settleDate, Expression<Func<TPos, bool>> predicate = null)
            where TPos : EodTradePosition
            where TRisk : EodTradeRisk
        {
            var bodDate = QdpCalendarHelper.GetNonHoliday(settleDate.AddDays(1));

            if (predicate == null)
            {
                predicate = PredicateBuilder.Create<TPos>(n => n.ValueDate == settleDate);
            }
            else
            {
                predicate = PredicateBuilder.Create<TPos>(n => n.ValueDate == settleDate).And(predicate);
            }

            // 带风险数据的重载与上面的持仓重载采用相同策略：除权记录不参与 SQL 左连接，
            // 先完成 EOD、BOD、Risk 的行级关联，再在内存中按标的代码查找唯一除权记录，
            // 防止除权表重复行复制风险记录。
            var query = from eod in DbContext.Set<TPos>().AsNoTracking().Where(predicate)
                        join bod in DbContext.BodTradePosition.Where(n => n.ValueDate == bodDate)
                        on new { eod.BookId, eod.TradeType, eod.PositionType, eod.UnderlyingCode, ExchangeOptionCode = eod.ExchangeOptionCode ?? string.Empty }
                        equals new { bod.BookId, bod.TradeType, bod.PositionType, bod.UnderlyingCode, ExchangeOptionCode = bod.ExchangeOptionCode ?? string.Empty } into t_bod
                        from bod in t_bod.DefaultIfEmpty()
                        join risk in DbContext.Set<TRisk>().AsNoTracking().Where(n => n.ValueDate == settleDate && n.TradeId > 0) on new { eod.ValueDate, eod.TradeId } equals new { risk.ValueDate, risk.TradeId } into risk_t
                        from risk in risk_t.DefaultIfEmpty()
                        select new
                        {
                            eod,
                            bod = bod == null ? null : new
                            {
                                bod.Amount,
                                bod.Cost,
                                //bod.AveragePrice
                            },
                            risk
                        };

            var datas = query.ToArray();
            var diviService = new TradeModule.DealModule.DividendService(OptUser);
            // 与无风险重载保持同一数据来源、日期条件和大小写无关的代码匹配规则；重复
            // 有效记录会在这里显式失败，而不是让一条持仓对应多条风险结果。
            var dividendDict = diviService.GetExDividendQuery(settleDate)
                .ToDictionary(O => O.UnderlyingCode, O => O, StringComparer.OrdinalIgnoreCase);
            var eodPriceProvider = new EodPriceProvider(settleDate);
            return datas.Select(data =>
            {
                var pos = data.eod;
                var bod = data.bod;
                // 风险对象的除权 Pv 重算规则与上一个重载保持一致，仅在股票交易类型下执行。
                if (dividendDict.TryGetValue(pos.UnderlyingCode, out var dividend))
                {
                    if (data.eod.TradeType == "股票")
                    {
                        var settlePrice = eodPriceProvider.GetPrice(data.eod.UnderlyingCode, SettlementTypeEnum.ClosePrice);
                        settlePrice = diviService.GetPrice(settlePrice, dividend);
                        var amount = diviService.GetPositionAmount(data.eod.Amount, dividend);
                        pos.Pv = pos.Pv > 0 ? Math.Abs(amount * settlePrice) : -Math.Abs(amount * settlePrice);
                    }
                }
                if (bod != null)
                {
                    pos.Amount = bod.Amount;
                    pos.Cost = bod.Cost;
                }
                return new EodTradePositionAndRisk(pos, data.risk);
            }).ToArray();
        }
    }
}