namespace KArtSell.Modules.ModelOperations.ShadowRun;

/// <summary>
/// Immutable result of shadow run evaluation.
/// Includes performance metrics, phase attribution, and validation gates.
/// </summary>
public sealed record ShadowRunResult(
    Guid RunId,
    Guid ModelId,
    DateOnly WindowStartDate,
    DateOnly WindowEndDate,
    ShadowRunStatus Status,
    ShadowRunMetrics Metrics,
    PhaseBreakdown PhaseAnalysis,
    CostAnalysis CostAnalysis,
    FalseExitAnalysis FalseExitAnalysis,
    ValidationGates ValidationGates,
    string? ErrorMessage = null,
    DateTimeOffset CreatedAt = default);

/// <summary>
/// Execution status of shadow run.
/// </summary>
public enum ShadowRunStatus
{
    Pending = 0,
    DataBackfill = 1,
    Replay = 2,
    EvaluationComplete = 3,
    Failed = 4
}

/// <summary>
/// Performance metrics for shadow run period.
/// </summary>
public sealed record ShadowRunMetrics(
    decimal TotalReturn,           // % return over period
    decimal SharpeRatio,           // Daily Sharpe ratio
    decimal CalmurRatio,           // Calmar ratio (return / max drawdown)
    decimal MaximumDrawdown,       // Peak-to-trough % loss
    decimal WinRate,               // % of profitable days
    decimal ProbOfBacktestOverfit, // PBO score (must be ≤ 20%)
    decimal DailySharePercentile,  // DSR percentile (must be ≥ 95%)
    int TradingDays);              // Actual trading days in period

/// <summary>
/// Market phase segmentation: Bull, Bear, Sideways, Volatility.
/// </summary>
public sealed record PhaseBreakdown(
    PhaseMetrics BullMarket,
    PhaseMetrics BearMarket,
    PhaseMetrics Sideways,
    PhaseMetrics HighVolatility);

public sealed record PhaseMetrics(
    int TradingDays,
    decimal Return,
    decimal Sharpe,
    decimal WinRate,
    decimal MaxDrawdown);

/// <summary>
/// Cost analysis: base scenario vs. 2x cost scenario.
/// </summary>
public sealed record CostAnalysis(
    decimal BaseScenarioReturn,
    decimal TwoXCostReturn,
    bool PassesTwoXPositive);  // TwoXCostReturn > 0

/// <summary>
/// False exit analysis: reentry success rate, duration out of position.
/// </summary>
public sealed record FalseExitAnalysis(
    int FalseExitCount,
    int ReentrySuccessCount,
    decimal ReentrySuccessRate,
    decimal AverageDaysOutOfPosition);

/// <summary>
/// Validation gates: pass/fail for production readiness.
/// </summary>
public sealed record ValidationGates(
    bool PboUnder20,              // PBO ≤ 20%
    bool DsrAbove95,              // DSR ≥ 95th percentile
    bool CostTwoXPositive,        // 2x cost scenario profitable
    bool AllGatesPassed);         // AND of all above