namespace Simulator.Services
{
    /// <summary>
    /// 시뮬레이션 인메모리 상태.
    /// 잔고, 포지션, 거래 내역을 관리합니다.
    /// </summary>
    public class SimState
    {
        private int _nextOrderId = 1000;

        public double       Balance       { get; set; }
        public SimPosition? LongPosition  { get; set; }
        public SimPosition? ShortPosition { get; set; }

        public List<SimTrade> TradeHistory { get; } = new();

        public SimState(double initialBalance)
        {
            Balance = initialBalance;
        }

        public string NextOrderId() => $"SIM{_nextOrderId++:D6}";

        /// <summary>모든 포지션을 Bitget all-position 응답 형식 목록으로 반환합니다.</summary>
        public List<object> GetAllPositions(string symbol, string productType, double currentPrice)
        {
            var result = new List<object>();

            if (LongPosition != null)
                result.Add(BuildPositionObject(LongPosition, symbol, productType, currentPrice));

            if (ShortPosition != null)
                result.Add(BuildPositionObject(ShortPosition, symbol, productType, currentPrice));

            return result;
        }

        private static object BuildPositionObject(
            SimPosition pos, string symbol, string productType, double currentPrice)
        {
            double unrealized = pos.Side == "long"
                ? (currentPrice - pos.AvgPrice) * pos.Size
                : (pos.AvgPrice - currentPrice) * pos.Size;

            return new
            {
                symbol           = symbol,
                productType      = productType,
                marginMode       = "crossed",
                holdSide         = pos.Side,
                openDelegateSize = pos.Size.ToString("F4"),
                margin           = "0",
                available        = pos.Size.ToString("F4"),
                locked           = "0",
                total            = pos.Size.ToString("F4"),
                leverage         = pos.Leverage.ToString(),
                achievedProfits  = "0",
                openPriceAvg     = pos.AvgPrice.ToString("F6"),
                posMode          = "hedge_mode",
                unrealizedPL     = unrealized.ToString("F4"),
                liquidationPrice = "0",
                keepMarginRate   = "0.004",
                markPrice        = currentPrice.ToString("F6"),
                marginRatio      = "0",
                cTime            = pos.OpenTime.ToUnixTimeMilliseconds().ToString(),
                uTime            = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds().ToString(),
            };
        }
    }

    public class SimPosition
    {
        public string        Side      { get; set; } = "";  // "long" | "short"
        public double        Size      { get; set; }
        public double        AvgPrice  { get; set; }
        public double        Leverage  { get; set; } = 10;
        public DateTimeOffset OpenTime { get; set; } = DateTimeOffset.UtcNow;
    }

    public class SimTrade
    {
        public DateTimeOffset Time   { get; set; }
        public string         Side   { get; set; } = "";
        public string         Action { get; set; } = "";
        public double         Size   { get; set; }
        public double         Price  { get; set; }
        public double         Pnl    { get; set; }
    }
}