using YLErp.DBModels;
using YLErp.DBModels.Enums;

namespace YLErp.Modules.SwapModule
{
    /// <summary>
    /// 端到端：盘中收益互换（DividendIn 由生产方法 GetPreEodDividendSum 真实算出）→ 保存 → EOD，
    /// 验证分红【不重复累计】（EOD TdCloseDividend 扣减 DividendIn）且【不丢失】（当日新计进 PosiDividendSum）。
    ///
    /// 与 MultiUnwindDividendConservationTest.MU_001 的区别：MU_001 的互换 DividendIn 是测试喂的常量；
    /// 本测试的 DividendIn 由生产方法 GetPreEodDividendSum 真实算出（读 EOD 快照），再喂给 EOD——
    /// 覆盖"预览算 DividendIn + EOD 扣减"的完整链路（MU_001 的缺口）。
    /// </summary>
    [TestClass]
    public class DividendEodNoDoubleCountTest
    {
        private const int SwapTradeId = 9200;
        private const long PositionId = 9201;
        private const decimal InitialQty = 1000m;
        private const decimal DailyRatePerUnit = 0.01m; // 每单位每天 0.01，便于手算
        private static readonly DateTime StartDate = new(2026, 1, 5);

        #region Stubs

        /// <summary>SwapDealService stub：暴露 GetPreEodDividendSum，注入 EOD 数据（不连库）。</summary>
        private sealed class DealSvcStub : SwapDealService
        {
            private readonly List<eod_swap> _eodSwaps;
            private readonly List<eod_swap_position> _eodPositions;
            public DealSvcStub(List<eod_swap> eodSwaps, List<eod_swap_position> eodPositions)
                : base(OptUserInfo.UnitTestUser) { _eodSwaps = eodSwaps; _eodPositions = eodPositions; }
            public decimal ExposeGetPreEodDividendSum(int tradeId, long positionId, DateTime dealDate)
                => GetPreEodDividendSum(tradeId, positionId, dealDate);
            protected override IQueryable<eod_swap> QueryPreEodSwaps(int tradeId)
                => _eodSwaps.Where(x => x.SwapTradeId == tradeId).AsQueryable();
            protected override eod_swap_position QueryPreEodPosition(int tradeId, long positionId, DateTime valueDate)
                => _eodPositions.FirstOrDefault(x => x.SwapTradeId == tradeId && x.PositionId == positionId && x.ValueDate == valueDate);
        }

        /// <summary>SwapEodPositionService stub：暴露 UpdateEodPosition/CopyEodPosition + 线性 CalcBondPayment。</summary>
        private sealed class EodSvcStub : TestableSwapEodPositionService
        {
            public EodSvcStub() : base(nameof(DividendEodNoDoubleCountTest)) { }
            protected override decimal CalcBondPayment(string underlyingCode, DateTime fromDate, DateTime toDate, decimal qty, int shortRatio, int directionRatio)
            {
                int days = Math.Max(0, (int)(toDate - fromDate).TotalDays);
                return DailyRatePerUnit * days * qty * shortRatio * directionRatio;
            }
            protected override underlying_manager GetUnderlyingData(string underlyingCode)
                => new underlying_manager { ValueAddedTax = 0m };
            protected override decimal GetUnderlyingPrice(string code, DateTime settleDate, out decimal vobp)
            { vobp = 0m; return 1.00m; }
            public eod_swap_position ExecuteUpdateEodPosition(swap_position swapPosition, eod_swap_position eod, trade td, DateTime valueDate, DateTime preSettleDate, List<swap_flow_event> unwindEvents)
                => UpdateEodPosition(swapPosition, eod, null, td, valueDate, preSettleDate, unwindEvents);
            public eod_swap_position ExecuteCopyEodPosition(eod_swap_position eod, trade td, DateTime valueDate, DateTime preSettleDate)
                => CopyEodPosition(eod, null, td, valueDate, preSettleDate);
        }

        #endregion

        #region 数据构建

        private static trade CreateTrade() => new trade
        {
            id = SwapTradeId, TradeNumber = "UT-DIV-EOD-001", ClientId = 999999,
            TradeType = "收益互换", TradeDate = StartDate, StartDate = StartDate,
            ExerciseDate = new DateTime(2027, 1, 5), TradeStatus = "确认成交", ValidState = "Valid",
            StructureType = "单标的", QuoteCurrency = "CNY", SettlementCurrency = "CNY",
            OriginalStockEqvNotional = (double)(InitialQty * 1.00m)
        };

        private static swap_position CreatePosition() => new swap_position
        {
            id = PositionId, SwapTradeId = SwapTradeId,
            PosiDirection = (int)SwapDirectionEnum.收取, PositionType = (int)PositionTypeFlag.Long,
            UnderlyingCode = "210210.IB", ContractSize = 1m,
            PosiQuantity = InitialQty, PosiNotionalValue = InitialQty,
            PosiNetPrice = 1.000m, PosiGrossPrice = 1.000m,
            PosiNetFeePrice = 1.000m, PosiNetNoFeePrice = 1.000m,
            IsInitial = true, Invalid = false,
            PosiTradingFee = 0, PosiTradingFeePending = 0
        };

        private static eod_swap_position CreateInitialEod() => new eod_swap_position
        {
            id = 1, SwapTradeId = SwapTradeId, PositionId = PositionId,
            ValueDate = StartDate, PosiQuantity = InitialQty,
            PosiDirection = (int)SwapDirectionEnum.收取, PositionType = (int)PositionTypeFlag.Long,
            UnderlyingCode = "210210.IB", ContractSize = 1m,
            PosiNetPrice = 1.000m, PosiGrossPrice = 1.000m,
            PosiNetFeePrice = 1.000m, PosiNetNoFeePrice = 1.000m,
            PosiDividendSum = 0m, TdPosiDividend = 0m, TdCloseDividend = 0m,
            RealizedDividend = 0m, PosiFeePending = 0m,
            InterestProfitSum = 0m, Invalid = false
        };

        private static swap_flow_event SwapEvent(decimal dividendIn, DateTime eventDate) => new swap_flow_event
        {
            SwapTradeId = SwapTradeId, EventType = (int)SwapFlowEventTypeEnum.互换,
            PositionId = PositionId, Quantity = 0m, DividendIn = dividendIn,
            MarkClosePnl = 0m, CloseFee = 0m, TradingFeePending = 0m,
            EventDate = eventDate, PayDate = eventDate,
            DataState = (int)SwapFlowDateStateEnum.完成
        };

        private static swap_flow_event CloseEvent(decimal qty, decimal dividendIn, DateTime eventDate) => new swap_flow_event
        {
            SwapTradeId = SwapTradeId, EventType = (int)SwapFlowEventTypeEnum.平仓,
            PositionId = PositionId, Quantity = qty, DividendIn = dividendIn,
            MarkClosePnl = 0m, CloseFee = 0m, TradingFeePending = 0m,
            TradingAmount = qty * 1.000m,
            UnwindDate = eventDate, EventDate = eventDate, PayDate = eventDate,
            DataState = (int)SwapFlowDateStateEnum.完成
        };

        private static void AssertDecimalEqual(decimal expected, decimal actual, decimal tol, string msg)
            => Assert.IsTrue(Math.Abs(expected - actual) <= tol, $"{msg}: expected={expected} actual={actual}");

        #endregion

        /// <summary>
        /// 盘中收益互换：DividendIn 由 GetPreEodDividendSum 真实算（读 T-1 EOD）→ 保存 → EOD。
        /// 验证：不重复（EOD TdCloseDividend 扣 DividendIn）+ 不丢失（当日新计进 PosiDividendSum）+ 守恒。
        ///
        /// 序列（StartDate=1/5，每日 0.01×1000=10）：
        ///   D1=1/6 无事件 Copy：PosiDividendSum = 0 + 10 = 10
        ///   D2=1/7 盘中互换：GetPreEodDividendSum(读 D1) → DividendIn=10；保存 swap_event；EOD：新计 10 - 实现 10 → PosiDividendSum=10
        /// 守恒：全程新计(10+10) - 全程实现(10) = 末尾 PosiDividendSum(10)
        /// </summary>
        [TestMethod]
        public void 盘中收益互换_DividendIn真实算_保存后EOD_不重复不丢失()
        {
            var eodSvc = new EodSvcStub();
            var td = CreateTrade();
            var position = CreatePosition();
            var initialEod = CreateInitialEod();

            // D1=1/6 无事件 EOD
            var d1 = new DateTime(2026, 1, 6);
            var r1 = eodSvc.ExecuteCopyEodPosition(initialEod, td, d1, StartDate);
            AssertDecimalEqual(10m, r1.PosiDividendSum, 0.01m, "D1 PosiDividendSum(0+1天×10)");

            // D2=1/7 盘中：DividendIn 由生产方法 GetPreEodDividendSum 真实算（读 D1 EOD，当日 EOD 未生成）
            var d2 = new DateTime(2026, 1, 7);
            var dealSvc = new DealSvcStub(
                new List<eod_swap> { new eod_swap { SwapTradeId = SwapTradeId, ValueDate = d1 } },
                new List<eod_swap_position> { r1 });
            decimal dividendIn = dealSvc.ExposeGetPreEodDividendSum(SwapTradeId, PositionId, d2);
            AssertDecimalEqual(10m, dividendIn, 0.01m, "盘中 DividendIn=GetPreEodDividendSum 读 T-1(D1)=10");
            Console.WriteLine($"[盘中预览] DividendIn={dividendIn}（读 T-1 EOD PosiDividendSum={r1.PosiDividendSum}）");

            // 保存互换事件（DividendIn=真实算出的值，模拟界面点收益互换后保存）
            var swapEvent = SwapEvent(dividendIn, d2);

            // D2=1/7 EOD（UpdateEodPosition，真实生产递推）
            var r2 = eodSvc.ExecuteUpdateEodPosition(position, r1, td, d2, d1, new List<swap_flow_event> { swapEvent });

            // 断言：不重复 + 不丢失
            AssertDecimalEqual(10m, r2.TdPosiDividend, 0.01m, "D2 当日新计(1天×10)");
            AssertDecimalEqual(dividendIn, r2.TdCloseDividend, 0.01m, "D2 TdCloseDividend=互换DividendIn（扣减→不重复累计）");
            AssertDecimalEqual(10m, r2.PosiDividendSum, 0.01m, "D2 PosiDividendSum=前日10+新计10-实现10=10（当日新计挂着→不丢失）");

            // 守恒：全程新计 - 全程实现 = 末尾 PosiDividendSum
            decimal totalNew = r1.TdPosiDividend + r2.TdPosiDividend;
            decimal totalRealized = r2.TdCloseDividend;
            AssertDecimalEqual(r2.PosiDividendSum, totalNew - totalRealized, 0.01m,
                $"守恒：末尾 PosiDividendSum({r2.PosiDividendSum}) = 全程新计({totalNew}) - 全程实现({totalRealized})");

            Console.WriteLine($"[EOD 后] TdPosiDividend={r2.TdPosiDividend} TdCloseDividend={r2.TdCloseDividend} PosiDividendSum={r2.PosiDividendSum}");
            Console.WriteLine($"结论：互换实现 {dividendIn} 被扣减（不重复）；当日新计 {r2.TdPosiDividend} 挂 PosiDividendSum（不丢失）");
        }

        /// <summary>
        /// 盘中全平（扣持仓→PosiQuantity=0）：验证登记日当日分红是否丢失。
        ///
        /// 全平 vs 收益互换的关键区别：全平扣持仓，EOD 时 PosiQuantity=0 → 当日新计 TdPosiDividend 不计提（:1834 守卫）
        /// + PosiDividendSum 归 0（:1856 else）。若盘中 DividendIn 读 T-1（漏当日新计），则当日分红
        /// 既没进 DividendIn、也没进 PosiDividendSum → 丢失。本测试暴露这个风险。
        ///
        /// 序列（StartDate=1/5，每日 0.01×1000=10）：
        ///   D1=1/6 无事件 Copy：PosiDividendSum=10
        ///   D2=1/7 盘中全平：DividendIn=GetPreEodDividendSum(读 D1)=10（漏 D2 当日）；EOD：PosiQuantity=0→TdPosiDividend=0, PosiDividendSum=0
        ///   应得（登记日持仓享当日）= D1累计(10) + D2当日(10) = 20；实拿 = DividendIn(10) + PosiDividendSum(0) = 10 → 丢失 10
        /// </summary>
        [TestMethod]
        public void 特征化_登记日全平_当日分红丢失10_已知缺陷待修复()
        {
            var eodSvc = new EodSvcStub();
            var td = CreateTrade();
            var position = CreatePosition();
            var initialEod = CreateInitialEod();

            // D1=1/6 无事件 EOD
            var d1 = new DateTime(2026, 1, 6);
            var r1 = eodSvc.ExecuteCopyEodPosition(initialEod, td, d1, StartDate);
            AssertDecimalEqual(10m, r1.PosiDividendSum, 0.01m, "D1 PosiDividendSum");

            // D2=1/7 盘中全平：DividendIn 由生产方法真实算（读 D1 EOD，当日 EOD 未生成）
            var d2 = new DateTime(2026, 1, 7);
            var dealSvc = new DealSvcStub(
                new List<eod_swap> { new eod_swap { SwapTradeId = SwapTradeId, ValueDate = d1 } },
                new List<eod_swap_position> { r1 });
            decimal dividendIn = dealSvc.ExposeGetPreEodDividendSum(SwapTradeId, PositionId, d2);
            AssertDecimalEqual(10m, dividendIn, 0.01m, "全平 DividendIn=读T-1(D1)=10（漏 D2 当日新计）");

            // 全平事件（扣全部持仓）
            var closeEvent = CloseEvent(InitialQty, dividendIn, d2);

            // D2=1/7 EOD（UpdateEodPosition，全平→PosiQuantity=0）
            var r2 = eodSvc.ExecuteUpdateEodPosition(position, r1, td, d2, d1, new List<swap_flow_event> { closeEvent });

            // 登记日持仓应享当日分红：D1累计 + D2当日（若持仓>0 本应计提 = 1天×0.01×1000=10）
            decimal d2AccrualIfHeld = DailyRatePerUnit * 1 * InitialQty;
            decimal expectedTotal = r1.PosiDividendSum + d2AccrualIfHeld;   // 应得 = 10 + 10 = 20
            decimal actualGot = dividendIn + r2.PosiDividendSum;             // 实拿 = DividendIn + 末尾挂着
            decimal lost = expectedTotal - actualGot;

            Console.WriteLine($"[全平] D1累计={r1.PosiDividendSum}, D2当日(若计提)={d2AccrualIfHeld}, 应得={expectedTotal}");
            Console.WriteLine($"[全平] DividendIn={dividendIn}, EOD:TdPosiDividend={r2.TdPosiDividend} PosiDividendSum={r2.PosiDividendSum} PosiQuantity={r2.PosiQuantity}");
            Console.WriteLine($"[全平] 实拿={actualGot}, 丢失={lost}");

            // 【特征化·已知缺陷】登记日盘中全平，当日分红丢失 10（D2当日新计既没进 DividendIn 也没进 PosiDividendSum）。
            // 根因：①盘中 DividendIn=GetPreEodDividendSum 读 T-1（当日 EOD 未生成，漏当日新计）；
            //       ②EOD 全平 PosiQuantity=0 → TdPosiDividend=0（:1834 不计提当日）+ PosiDividendSum=0（:1856）。
            // 待修复：GetPreEodDividendSum 当日 EOD 不存在时补算当日分红，或全平 EOD 按登记日持仓计提。
            // 修复后改回 AssertDecimalEqual(0m, lost, ...)（不丢失）。
            AssertDecimalEqual(10m, lost, 0.01m,
                $"【已知缺陷】登记日盘中全平当日分红丢失={lost}（应得{expectedTotal}, 实拿{actualGot}）。待修复。");
        }
    }
}