using YLErp.Abstract;
using YLErp.BLL;
using YLErp.DBModels;
using YLErp.Helpers;

namespace YLErp.Modules.EodModule
{
    /// <summary>
    /// 收盘后按交易日推送 TRS 合约全量快照。
    /// </summary>
    public class TrsContractKafkaPushService
    {
        private const string DateFormat = "yyyy-MM-dd";
        private const string DateTimeFormat = "yyyy-MM-dd HH:mm:ss";
        private const string InterestCategory = "互换利率";
        private const int TrsContractPushType = 1;
        private const int MaxAttempts = 3;

        private readonly YLContext _dbContext;
        private readonly IKafkaProduce _kafkaProduce;
        private readonly string _topic;
        private readonly IYcLogger _logger;

        public TrsContractKafkaPushService(YLContext dbContext, IKafkaProduce kafkaProduce, string topic)
        {
            _dbContext = dbContext ?? throw new ArgumentNullException(nameof(dbContext));
            _kafkaProduce = kafkaProduce ?? throw new ArgumentNullException(nameof(kafkaProduce));
            _topic = string.IsNullOrWhiteSpace(topic) ? throw new ArgumentException("Kafka topic is empty", nameof(topic)) : topic;
            _logger = LogFactory.GetLogger(nameof(TrsContractKafkaPushService));
        }

        public void Push(DateTime valueDate)
        {
            valueDate = valueDate.Date;

            TrsContractSnapshot snapshot;
            string payload;
            try
            {
                snapshot = BuildSnapshot(valueDate);
                payload = JsonHelper.Serialize(snapshot, true, true);
            }
            catch (Exception ex)
            {
                _logger.Error($"TRS contract snapshot build failed, valueDate:{valueDate:yyyy-MM-dd}", ex);
                RecordFailures(valueDate, 0, ex);
                return;
            }

            var key = valueDate.ToString(DateFormat);
            Exception lastException = null;
            for (var attempt = 1; attempt <= MaxAttempts; attempt++)
            {
                try
                {
                    _kafkaProduce.Produce(_topic, key, payload);
                    _logger.Info($"TRS contract snapshot sent, valueDate:{key}, topic:{_topic}, count:{snapshot.ContractCount}, attempt:{attempt}");
                    return;
                }
                catch (Exception ex)
                {
                    lastException = ex;
                    _logger.Error($"TRS contract snapshot send failed, valueDate:{key}, topic:{_topic}, attempt:{attempt}", ex);
                }
            }

            _logger.Error($"TRS contract snapshot send exhausted retries, valueDate:{key}, topic:{_topic}, attempts:{MaxAttempts}");
            RecordFailures(valueDate, MaxAttempts, lastException);
        }

        protected virtual void RecordFailures(DateTime valueDate, int retryCount, Exception exception)
        {
            try
            {
                var recordIds = _dbContext.eod_swap
                    .Where(x => x.ValueDate == valueDate)
                    .Select(x => x.id)
                    .ToList();
                if (recordIds.Count == 0)
                {
                    recordIds.Add(0);
                }

                var now = DateTime.Now;
                var statuses = _dbContext.push_status
                    .Where(x => x.ValueDate == valueDate
                        && x.PushType == TrsContractPushType
                        && recordIds.Contains(x.RecordId))
                    .ToList();
                var error = exception?.ToString();
                if (error?.Length > 2000)
                {
                    error = error.Substring(0, 2000);
                }

                foreach (var recordId in recordIds)
                {
                    var status = statuses.FirstOrDefault(x => x.RecordId == recordId);
                    if (status == null)
                    {
                        status = new PushStatus
                        {
                            ValueDate = valueDate,
                            PushType = TrsContractPushType,
                            RecordId = recordId,
                            CreateTime = now
                        };
                        _dbContext.push_status.Add(status);
                    }

                    status.State = PushStateEnum.失败;
                    status.RetryCount = retryCount;
                    status.LastError = error;
                    status.PushTime = now;
                    status.UpdateTime = now;
                }

                _dbContext.SaveChanges();
            }
            catch (Exception ex)
            {
                _logger.Error($"TRS contract push failure status save failed, valueDate:{valueDate:yyyy-MM-dd}", ex);
            }
        }

        protected virtual TrsContractSnapshot BuildSnapshot(DateTime valueDate)
        {
            var eodSwaps = _dbContext.eod_swap
                .Where(x => x.ValueDate == valueDate)
                .AsNoTracking()
                .ToList();
            var tradeIds = eodSwaps.Select(x => x.SwapTradeId).Distinct().ToList();
            var trades = _dbContext.trade
                .Where(x => tradeIds.Contains(x.id))
                .AsNoTracking()
                .ToDictionary(x => x.id);
            var eodPositions = _dbContext.eod_swap_position
                .Where(x => x.ValueDate == valueDate && tradeIds.Contains(x.SwapTradeId) && !x.Invalid)
                .AsNoTracking()
                .ToList();
            var positionIds = eodPositions.Select(x => x.PositionId).Distinct().ToList();
            var swapPositions = _dbContext.swap_position
                .Where(x => positionIds.Contains(x.id) && !x.Invalid && x.category_tag == InterestCategory)
                .AsNoTracking()
                .ToDictionary(x => x.id);

            var contracts = eodSwaps.Select(eodSwap => BuildContract(eodSwap, trades, eodPositions, swapPositions)).ToList();
            return new TrsContractSnapshot
            {
                SchemaVersion = "v1",
                ValueDate = valueDate.ToString(DateFormat),
                PushTime = DateTime.Now.ToString(DateTimeFormat),
                ContractCount = contracts.Count,
                Contracts = contracts
            };
        }

        internal static TrsContractSnapshotItem BuildContract(
            eod_swap eodSwap,
            IReadOnlyDictionary<int, trade> trades,
            IReadOnlyCollection<eod_swap_position> eodPositions,
            IReadOnlyDictionary<long, swap_position> swapPositions)
        {
            if (!trades.TryGetValue(eodSwap.SwapTradeId, out var trade))
            {
                throw new InvalidOperationException($"TRS trade not found, swapTradeId:{eodSwap.SwapTradeId}");
            }

            var positions = eodPositions.Where(x => x.SwapTradeId == eodSwap.SwapTradeId).ToList();
            var floating = positions.Where(x => !string.IsNullOrWhiteSpace(x.UnderlyingCode) && swapPositions.ContainsKey(x.PositionId)).ToList();
            var interest = positions.Where(x => string.IsNullOrWhiteSpace(x.UnderlyingCode)
                && ConsTrade.InterestModels.Contains(x.InterestMode)
                && swapPositions.TryGetValue(x.PositionId, out var swapPosition)
                && swapPosition.category_tag == InterestCategory).ToList();

            if (floating.Count != 1 || interest.Count != 1)
            {
                throw new InvalidOperationException($"TRS legs invalid, swapTradeId:{eodSwap.SwapTradeId}, floating:{floating.Count}, interest:{interest.Count}");
            }

            var interestLeg = interest[0];
            var floatingLeg = floating[0];
            return new TrsContractSnapshotItem
            {
                TradeDate = eodSwap.ValueDate.ToString(DateFormat),
                BookId = eodSwap.BookId,
                SwapTradeNo = eodSwap.SwapTradeNo,
                ClientId = eodSwap.ClientId,
                UnderlyingCode = trade.UnderlyingCode,
                UnderlyingName = trade.UnderlyingAssetName,
                UnderlyingInstrumentType = trade.UnderlyingInstrumentType,
                NotionalValue = eodSwap.NotionalValue,
                Dv01 = eodSwap.dv01 ?? 0,
                StartDate = trade.StartDate?.ToString(DateFormat),
                MaturityDate = trade.ExerciseDate?.ToString(DateFormat),
                FixedRate = interestLeg.InterestRateDefault,
                InterestDirection = interestLeg.InterestDirection,
                FloatingDirection = floatingLeg.PositionType,
                InitMarginGain = eodSwap.InitMarginGain,
                InitMarginLoss = eodSwap.InitMarginLoss
            };
        }
    }

    public class TrsContractSnapshot
    {
        public string SchemaVersion { get; set; }
        public string ValueDate { get; set; }
        public string PushTime { get; set; }
        public int ContractCount { get; set; }
        public List<TrsContractSnapshotItem> Contracts { get; set; }
    }

    public class TrsContractSnapshotItem
    {
        public string TradeDate { get; set; }
        public int BookId { get; set; }
        public string SwapTradeNo { get; set; }
        public int ClientId { get; set; }
        public string UnderlyingCode { get; set; }
        public string UnderlyingName { get; set; }
        public string UnderlyingInstrumentType { get; set; }
        public decimal NotionalValue { get; set; }
        public decimal Dv01 { get; set; }
        public string StartDate { get; set; }
        public string MaturityDate { get; set; }
        public decimal FixedRate { get; set; }
        public int InterestDirection { get; set; }
        public int FloatingDirection { get; set; }
        public decimal InitMarginGain { get; set; }
        public decimal InitMarginLoss { get; set; }
    }
}