using Microsoft.VisualStudio.TestTools.UnitTesting;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using YLErp.DBModels;
using YLErp.DBModels.Enums;
using YLErp.Model;

namespace YLErp.Modules.SwapModule
{
    /// <summary>
    /// 录制服务：继承 SwapFlowEventService，override OnBefore/OnAfterMergePageEvent 钩子，
    /// 在真实的簿记流程中捕获簿记前的持仓快照和簿记后的事件，保存为黄金文件。
    ///
    /// 使用方式：在 SwapTrade2Controller 中临时替换 SwapFlowEventService 为此类即可。
    /// 录制完成后恢复原服务。
    /// </summary>
    public class RecordingSwapFlowEventService : SwapFlowEventService
    {
        private static readonly string GoldenDir = Path.Combine(
            AppDomain.CurrentDomain.BaseDirectory, "Resources", "GoldenFiles", "SwapFlowEvent");

        private static readonly JsonSerializerSettings JsonSettings = new JsonSerializerSettings
        {
            Formatting = Formatting.Indented,
            NullValueHandling = NullValueHandling.Include,
            DateFormatString = "yyyy-MM-ddTHH:mm:ss"
        };

        private static readonly object _lock = new object();
        private static int _recordCount = 0;
        private readonly int _maxRecords;

        public RecordingSwapFlowEventService(OptUserInfo optUser, int maxRecords = 50) : base(optUser)
        {
            _maxRecords = maxRecords;
        }

        protected override void OnBeforeMergePageEvent(
            int swapTradeId, DateTime tradeDate,
            trade trade, trade_extend tradeExtend,
            List<swap_flow_merge> merges, List<swap_position> positions)
        {
            // 不做任何事，等 OnAfter 里一起保存
        }

        protected override void OnAfterMergePageEvent(
            int swapTradeId, DateTime tradeDate,
            List<swap_flow_event> resultEvents)
        {
            if (resultEvents == null || resultEvents.Count == 0) return;

            lock (_lock)
            {
                if (_recordCount >= _maxRecords) return;
                _recordCount++;

                try
                {
                    var firstEvt = resultEvents[0];
                    var scenarioId = ClassifyFromEvents(resultEvents);
                    var fileName = $"recorded_s{scenarioId}_{swapTradeId}_{tradeDate:yyyyMMdd}_{_recordCount}.json";

                    // 注意：这里 trade/tradeExtend/merges/positions 已在 OnBefore 中拿到
                    // 但 OnAfter 不传这些参数，需要在这里重新查一次（此时数据可能已变更）
                    // 所以这个录制模式最好配合 OnBefore 一起使用
                    // 简化方案：只记录事件，在专门的测试中做完整录制

                    var goldenData = new GoldenFileModel
                    {
                        Scenario = GetScenarioName(scenarioId),
                        ScenarioId = scenarioId,
                        SwapTradeId = swapTradeId,
                        TradeDate = tradeDate,
                        UnderlyingCode = firstEvt.UnderlyingCode,
                        InputMerges = new JArray(),  // 需要在 OnBefore 中填充
                        InputPositions = new JArray(),
                        ExpectedEvents = JArray.FromObject(resultEvents, JsonSerializer.Create(JsonSettings)),
                        SourceDb = "recording-hook",
                        RecordedAt = DateTime.Now
                    };

                    Directory.CreateDirectory(GoldenDir);
                    var filePath = Path.Combine(GoldenDir, fileName);
                    File.WriteAllText(filePath, JsonConvert.SerializeObject(goldenData, JsonSettings));
                }
                catch { /* 录制不应影响正常业务 */ }
            }
        }

        private int ClassifyFromEvents(List<swap_flow_event> events)
        {
            var hasOpen = events.Any(x => x.EventType == (int)SwapFlowEventTypeEnum.开仓);
            var hasClose = events.Any(x => x.EventType == (int)SwapFlowEventTypeEnum.平仓);

            if (hasOpen && !hasClose) return 1;
            if (hasClose && !hasOpen) return 3;
            if (hasOpen && hasClose) return events.Count >= 3 ? 6 : 4;
            return 6;
        }

        private string GetScenarioName(int id) => id switch
        {
            1 => "单条+无持仓→开仓",
            3 => "单条+有持仓反向→平仓",
            4 => "单条+反向有余→平仓+开仓",
            5 => "两条+无持仓→一开一平",
            6 => "两条+有持仓→复杂组合",
            _ => "未知"
        };

        /// <summary>重置录制计数器（每次测试前调用）</summary>
        public static void ResetCount() { lock (_lock) _recordCount = 0; }
    }

    /// <summary>
    /// 用数据库直接做完整录制：模拟 MergePageEvent 的输入，但在执行前捕获完整上下文。
    /// 这个测试在连 DB 环境下运行，捕获簿记前一刻的持仓状态。
    /// </summary>
    [TestClass]
    public class SwapFlowEventFullRecordingTest
    {
        private static readonly string GoldenDir = Path.Combine(
            AppDomain.CurrentDomain.BaseDirectory, "Resources", "GoldenFiles", "SwapFlowEvent");

        private static readonly JsonSerializerSettings JsonSettings = new JsonSerializerSettings
        {
            Formatting = Formatting.Indented,
            NullValueHandling = NullValueHandling.Include,
            DateFormatString = "yyyy-MM-ddTHH:mm:ss"
        };

        /// <summary>
        /// 从数据库找有完整上下文的事件，录制完整黄金文件（含簿记前持仓）
        /// 策略：找最近的开仓事件（因为开仓时的持仓必然为 0 或同向），
        ///       以及平仓事件（需要找到平仓前一刻的持仓数量）
        /// </summary>
        /// <summary>
        /// 仅在需要重新录制黄金文件时手动启用。需要数据库连接。
        /// 正常测试运行时跳过此测试，避免生成无效的黄金文件。
        /// </summary>
        [TestMethod]
        [TestCategory("DBRecording")]
        [Ignore]
        public void FullRecord_WithPreBookingPositions()
        {
            using var db = DbContextFactory.GetYLDbContext();

            // 找所有有标的代码的事件，只取"流水自动"产生的事件（排除手工操作等同日多次操作）
            var allEvents = db.swap_flow_event
                .Where(x => !string.IsNullOrEmpty(x.UnderlyingCode) && x.ClientId > 0)
                .AsEnumerable();

            // 按 (SwapTradeId, EventDate, UnderlyingCode, OptLog) 分组，
            // 确保每组事件来自同一次 MergePageEvent 调用
            var eventGroups = allEvents
                .Where(x => x.OptLog == "流水自动")
                .GroupBy(x => new { x.SwapTradeId, x.EventDate, x.UnderlyingCode })
                .ToList();

            Console.WriteLine($"总事件分组: {eventGroups.Count}");

            // 需要找到"刚完成的事件"对应的 merge 数据
            // 完整的 merge 数据 + 未被修改的持仓数据 = 理想的黄金文件
            // 实际上 merge 数据在 DataState=完成后还在 DB 中
            var savedByScenario = new Dictionary<int, int>();
            int totalSaved = 0;

            foreach (var group in eventGroups)
            {
                var events = group.ToList();
                int scenarioId = Classify(events);
                if (!savedByScenario.ContainsKey(scenarioId))
                    savedByScenario[scenarioId] = 0;
                if (savedByScenario[scenarioId] >= 3) continue;

                var firstEvt = events[0];

                // 查 merge
                var merges = db.swap_flow_merge
                    .Where(x => x.SwapTradeId == firstEvt.SwapTradeId
                        && x.OccurTime == firstEvt.EventDate
                        && x.UnderlyingCode == firstEvt.UnderlyingCode)
                    .ToList();

                if (merges.Count == 0) continue;

                // 查持仓：这是关键 - 查当前时刻的持仓
                // 对于场景1（纯开仓），不需要持仓数据
                // 对于其他场景，我们需要"簿记前"的持仓
                // 但当前持仓是簿记后的，需要从事件反推簿记前持仓
                var positions = db.swap_position
                    .Where(x => x.SwapTradeId == firstEvt.SwapTradeId
                        && x.UnderlyingCode == firstEvt.UnderlyingCode
                        && !x.IsInitial && !x.Invalid)
                    .AsNoTracking()
                    .ToList();

                // 从事件反推簿记前的持仓
                var preBookingPositions = ReconstructPreBookingPositions(events, positions, merges);

                var trade = db.trade.Find(firstEvt.SwapTradeId);
                var tradeExtend = db.trade_extend.FirstOrDefault(x => x.TradeId == firstEvt.SwapTradeId);

                var goldenData = new GoldenFileModel
                {
                    Scenario = GetScenarioName(scenarioId),
                    ScenarioId = scenarioId,
                    SwapTradeId = firstEvt.SwapTradeId,
                    TradeDate = firstEvt.EventDate,
                    UnderlyingCode = firstEvt.UnderlyingCode,
                    InputMerges = JArray.FromObject(merges, JsonSerializer.Create(JsonSettings)),
                    InputPositions = JArray.FromObject(preBookingPositions, JsonSerializer.Create(JsonSettings)),
                    InputTrade = trade != null ? JObject.FromObject(trade, JsonSerializer.Create(JsonSettings)) : null,
                    InputTradeExtend = tradeExtend != null ? JObject.FromObject(tradeExtend, JsonSerializer.Create(JsonSettings)) : null,
                    ExpectedEvents = JArray.FromObject(events, JsonSerializer.Create(JsonSettings)),
                    SourceDb = "full-recording",
                    RecordedAt = DateTime.Now
                };

                Directory.CreateDirectory(GoldenDir);
                var idx = savedByScenario[scenarioId] + 1;
                var fileName = $"full_s{scenarioId}_sample{idx}_{firstEvt.SwapTradeId}_{firstEvt.EventDate:yyyyMMdd}.json";
                File.WriteAllText(Path.Combine(GoldenDir, fileName), JsonConvert.SerializeObject(goldenData, JsonSettings));

                savedByScenario[scenarioId]++;
                totalSaved++;

                Console.WriteLine($"  Saved {fileName} (merge={merges.Count} pos={preBookingPositions.Count} events={events.Count})");
            }

            Console.WriteLine("\n=== 录制结果 ===");
            foreach (var kv in savedByScenario.OrderBy(x => x.Key))
                Console.WriteLine($"场景{kv.Key}: {kv.Value}个");
            Console.WriteLine($"总计: {totalSaved}个");

            Assert.IsTrue(totalSaved > 0, "至少录制1个");
        }

        /// <summary>
        /// 核心：从事件结果反推簿记前的持仓状态
        /// 逻辑：
        /// - 平仓事件说明之前有反向持仓，数量=平仓数量
        /// - 持仓的 PosiGrossPrice 可以从平仓金额公式反推
        /// </summary>
        private List<swap_position> ReconstructPreBookingPositions(
            List<swap_flow_event> events,
            List<swap_position> currentPositions,
            List<swap_flow_merge> merges)
        {
            var result = new List<swap_position>();
            var closeEvents = events.Where(x => x.EventType == (int)SwapFlowEventTypeEnum.平仓).ToList();

            if (closeEvents.Count == 0) return result; // 纯开仓不需要持仓

            var firstClose = closeEvents[0];
            var firstMerge = merges[0];

            // 找到与平仓事件 PositionId 匹配的持仓记录
            var posRecord = currentPositions.FirstOrDefault(x => x.PositionId == firstClose.PositionId);

            // 平仓前持仓数量 = 平仓数量
            // 平仓前的 PosiGrossPrice = 该持仓的期初价格
            // 从平仓金额公式反推: amount = (flowMergeAvg - PosiGrossPrice) * unwindQty * ContractSize
            // => PosiGrossPrice = flowMergeAvg - amount / (unwindQty * ContractSize)

            decimal preBookingQty = firstClose.Quantity;
            decimal posiGrossPrice = firstMerge.TradingAmountAvgAbs; // 默认值

            if (firstClose.MarkClosePnl != 0 && preBookingQty != 0 && firstMerge.ContractSize != 0)
            {
                posiGrossPrice = firstMerge.TradingAmountAvgAbs - firstClose.MarkClosePnl / (preBookingQty * firstMerge.ContractSize);
            }

            var reconstructed = new swap_position
            {
                PositionId = firstClose.PositionId,
                SwapTradeId = firstClose.SwapTradeId,
                UnderlyingCode = firstClose.UnderlyingCode,
                PositionType = firstClose.PositionType, // 被平仓的方向
                PosiDirection = firstClose.PayDirection,
                PosiQuantity = preBookingQty,
                PosiGrossPrice = posiGrossPrice,
                PosiNetPrice = posiGrossPrice, // 近似
                ContractSize = firstMerge.ContractSize,
                IsInitial = false,
                Invalid = false,
                PosiTradingFee = posRecord?.PosiTradingFee ?? 0,
                UnderlyingInstrumentType = firstClose.UnderlyingInstrumentType
            };

            result.Add(reconstructed);
            return result;
        }

        private int Classify(List<swap_flow_event> events)
        {
            var hasOpen = events.Any(x => x.EventType == (int)SwapFlowEventTypeEnum.开仓);
            var hasClose = events.Any(x => x.EventType == (int)SwapFlowEventTypeEnum.平仓);

            if (hasOpen && !hasClose) return 1;
            if (hasClose && !hasOpen) return 3;
            if (hasOpen && hasClose) return events.Count >= 3 ? 6 : 4;
            return 6;
        }

        private string GetScenarioName(int id) => id switch
        {
            1 => "单条+无持仓→开仓",
            3 => "单条+有持仓反向→平仓",
            4 => "单条+反向有余→平仓+开仓",
            5 => "两条+无持仓→一开一平",
            6 => "两条+有持仓→复杂组合",
            _ => "未知"
        };
    }

    /// <summary>
    /// 黄金文件数据模型（录制/回放 MergePageEvent 用）
    /// </summary>
    public class GoldenFileModel
    {
        public string Scenario { get; set; }
        public int ScenarioId { get; set; }
        public int SwapTradeId { get; set; }
        public DateTime TradeDate { get; set; }
        public string UnderlyingCode { get; set; }

        /// <summary>输入：汇总流水列表</summary>
        public JArray InputMerges { get; set; }

        /// <summary>输入：已有持仓列表（可能为空）</summary>
        public JArray InputPositions { get; set; }

        /// <summary>输入：交易主信息</summary>
        public JObject InputTrade { get; set; }

        /// <summary>输入：交易扩展信息（含 FlowBookMode、Direction、SettlementRules）</summary>
        public JObject InputTradeExtend { get; set; }

        /// <summary>期望输出：开平仓事件列表</summary>
        public JArray ExpectedEvents { get; set; }

        /// <summary>录制时间</summary>
        public DateTime RecordedAt { get; set; } = DateTime.Now;

        /// <summary>录制来源数据库</summary>
        public string SourceDb { get; set; } = "test";
    }
}