namespace KArtSell.Integration.Tests.SellDecision;

using KArtSell.Modules.ModelOperations.SellDecision;
using Xunit;

public class PboValidatorTests
{
    private readonly IPboValidator _validator = new PboValidator();

    [Fact]
    public void ValidatePboScore_ValidScore_ReturnsTrue()
    {
        var (isValid, reason) = _validator.ValidatePboScore(0.72m, 0.65m);
        Assert.True(isValid);
        Assert.Contains(">=", reason);
    }

    [Fact]
    public void ValidatePboScore_InvalidScore_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidatePboScore(0.55m, 0.65m);
        Assert.False(isValid);
        Assert.Contains("Backtest overfit risk", reason);
    }

    [Fact]
    public void ValidatePboScore_NullScore_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidatePboScore(null, 0.65m);
        Assert.False(isValid);
        Assert.Contains("not yet available", reason);
    }
}

public class DsrValidatorTests
{
    private readonly IDsrValidator _validator = new DsrValidator();

    [Fact]
    public void ValidateDsrMetric_ValidMetric_ReturnsTrue()
    {
        var (isValid, reason) = _validator.ValidateDsrMetric(0.018m, 0.015m);
        Assert.True(isValid);
        Assert.Contains(">=", reason);
    }

    [Fact]
    public void ValidateDsrMetric_InvalidMetric_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidateDsrMetric(0.010m, 0.015m);
        Assert.False(isValid);
        Assert.Contains("Daily Sharpe ratio", reason);
    }

    [Fact]
    public void ValidateDsrMetric_NullMetric_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidateDsrMetric(null, 0.015m);
        Assert.False(isValid);
        Assert.Contains("not yet available", reason);
    }
}

public class OosValidatorTests
{
    private readonly IOosValidator _validator = new OosValidator();

    [Fact]
    public void ValidateOosPerformance_ValidReturn_ReturnsTrue()
    {
        var (isValid, reason) = _validator.ValidateOosPerformance("0.08", 0.05m);
        Assert.True(isValid);
        Assert.Contains(">=", reason);
    }

    [Fact]
    public void ValidateOosPerformance_InvalidReturn_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidateOosPerformance("0.03", 0.05m);
        Assert.False(isValid);
        Assert.Contains("underperforms", reason);
    }

    [Fact]
    public void ValidateOosPerformance_NullData_ReturnsFalse()
    {
        var (isValid, reason) = _validator.ValidateOosPerformance(null, 0.05m);
        Assert.False(isValid);
        Assert.Contains("not yet available", reason);
    }
}

public class SellPriorityRankerTests
{
    private readonly ISellPriorityRanker _ranker = new SellPriorityRanker();

    [Fact]
    public void RankByPolicy_HardImpairment_ReturnsHardImpairment()
    {
        var priority = _ranker.RankByPolicy(drawdown: -0.35m, marginRatio: 0.5m, concentration: 0.1m, liquidity: 0.8m, daysHeld: 100);
        Assert.Equal(SellPriority.HardImpairment, priority);
    }

    [Fact]
    public void RankByPolicy_PortfolioSurvival_ReturnsPortfolioSurvival()
    {
        var priority = _ranker.RankByPolicy(drawdown: 0m, marginRatio: 0.15m, concentration: 0.1m, liquidity: 0.8m, daysHeld: 100);
        Assert.Equal(SellPriority.PortfolioSurvival, priority);
    }

    [Fact]
    public void RankByPolicy_Concentration_ReturnsConcentration()
    {
        var priority = _ranker.RankByPolicy(drawdown: -0.05m, marginRatio: 0.5m, concentration: 0.3m, liquidity: 0.8m, daysHeld: 100);
        Assert.Equal(SellPriority.Concentration, priority);
    }

    [Fact]
    public void CalculateScore_HardImpairment_ReturnsLowestScore()
    {
        var score = _ranker.CalculateScore(SellPriority.HardImpairment, fundAgeDays: 400, liquidityPercent: 0.5m);
        Assert.Equal(950m, score); // 1000 - 50 (age boost, fundAgeDays > 365 per VS-10-SLICE_SPEC.md)
    }

    [Fact]
    public void CalculateScore_ReentryOption_ReturnsHighestScore()
    {
        var score = _ranker.CalculateScore(SellPriority.ReentryOption, fundAgeDays: 100, liquidityPercent: 0.5m);
        Assert.Equal(50m, score); // No boosts applied
    }

    [Fact]
    public void CalculateScore_IlliquidFund_ReducesScore()
    {
        var scoreHighLiquidity = _ranker.CalculateScore(SellPriority.Concentration, fundAgeDays: 100, liquidityPercent: 0.5m);
        var scoreLowLiquidity = _ranker.CalculateScore(SellPriority.Concentration, fundAgeDays: 100, liquidityPercent: 0.1m);
        Assert.True(scoreLowLiquidity < scoreHighLiquidity); // Illiquid = higher priority (lower score)
    }
}

public class SellDecisionEntityTests
{
    [Fact]
    public void SellDecisionEntity_CreatedWithAllFields_StoresCorrectly()
    {
        var now = DateTime.UtcNow;
        var entity = new SellDecisionEntity
        {
            Id = Guid.NewGuid(),
            ModelId = Guid.NewGuid(),
            Status = "PENDING",
            PboScore = 0.72m,
            DsrMetric = 0.018m,
            OosPerformance = "0.08",
            SellPriority = 1,
            TargetQuantity = 500,
            TargetPrice = 150.25m,
            CreatedAt = now,
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            PublishedAt = now,
            CorrelationId = Guid.NewGuid(),
            Revision = 1
        };

        Assert.Equal("PENDING", entity.Status);
        Assert.Equal(0.72m, entity.PboScore);
    }
}

public class SellDecisionStateTransitionTests
{
    [Theory]
    [InlineData("PENDING", "SIGNAL_GENERATED", true)]
    [InlineData("SIGNAL_GENERATED", "PBO_VALIDATED", true)]
    [InlineData("PBO_VALIDATED", "DSR_VALIDATED", true)]
    [InlineData("DSR_VALIDATED", "OOS_APPROVED", true)]
    [InlineData("OOS_APPROVED", "READY_FOR_APPROVAL", true)]
    [InlineData("READY_FOR_APPROVAL", "APPROVED", true)]
    [InlineData("APPROVED", "EXECUTED", true)]
    [InlineData("EXECUTED", "CONFIRMED", true)]
    [InlineData("PENDING", "APPROVED", false)] // Invalid: skipping states
    public void StateTransition_ValidatesAllowedPaths(string fromState, string toState, bool shouldBeValid)
    {
        var validTransitions = new[]
        {
            ("PENDING", "SIGNAL_GENERATED"),
            ("SIGNAL_GENERATED", "PBO_VALIDATED"),
            ("PBO_VALIDATED", "DSR_VALIDATED"),
            ("DSR_VALIDATED", "OOS_APPROVED"),
            ("OOS_APPROVED", "READY_FOR_APPROVAL"),
            ("READY_FOR_APPROVAL", "APPROVED"),
            ("APPROVED", "EXECUTED"),
            ("EXECUTED", "CONFIRMED")
        };

        var isValid = validTransitions.Contains((fromState, toState));
        Assert.Equal(shouldBeValid, isValid);
    }
}

public class SellDecisionPitTrackingTests
{
    [Fact]
    public void SellDecision_IncludesCorrelationIdForTracing()
    {
        var correlationId = Guid.NewGuid();
        var entity = new SellDecisionEntity
        {
            Id = Guid.NewGuid(),
            ModelId = Guid.NewGuid(),
            Status = "PENDING",
            OosPerformance = "0.08",
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            CorrelationId = correlationId,
            PublishedAt = DateTime.UtcNow,
            Revision = 1
        };

        Assert.Equal(correlationId, entity.CorrelationId);
    }

    [Fact]
    public void SellDecision_TracksRevisionOnUpdate()
    {
        var entity = new SellDecisionEntity
        {
            Status = "PENDING",
            OosPerformance = "0.08",
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            Revision = 1
        };
        entity.Revision++; // Simulate update

        Assert.Equal(2, entity.Revision);
    }

    [Fact]
    public void SellDecision_HasPublishedAtTimestamp()
    {
        var now = DateTime.UtcNow;
        var entity = new SellDecisionEntity
        {
            Id = Guid.NewGuid(),
            Status = "PENDING",
            OosPerformance = "0.08",
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            PublishedAt = now
        };

        Assert.Equal(now, entity.PublishedAt);
    }
}

public class SellDecisionIdempotencyTests
{
    [Fact]
    public void SellDecision_WithSameCorrelationId_ShouldBeTreatedAsIdempotent()
    {
        var correlationId = Guid.NewGuid();
        var decision1 = new SellDecisionEntity
        {
            Id = Guid.NewGuid(),
            Status = "PENDING",
            OosPerformance = "0.08",
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            CorrelationId = correlationId,
            Revision = 1
        };
        var decision2 = new SellDecisionEntity
        {
            Id = Guid.NewGuid(),
            Status = "PENDING",
            OosPerformance = "0.08",
            CreatedBy = "user@example.com",
            CreatedJustification = "test",
            CorrelationId = correlationId,
            Revision = 1
        };

        // Both have same correlation ID, so duplicate creation should be rejected
        Assert.Equal(decision1.CorrelationId, decision2.CorrelationId);
    }
}

public class SellDecisionContractIntegrationTests
{
    [Fact]
    public void CreateSellDecisionRequest_ValidatesAllRequiredFields()
    {
        var request = new CreateSellDecisionRequest
        {
            ModelId = Guid.NewGuid(),
            WindowStart = DateTime.UtcNow.AddDays(-90),
            WindowEnd = DateTime.UtcNow,
            ThresholdPbo = 0.65m,
            ThresholdDsr = 0.015m,
            Justification = "Model consensus"
        };

        Assert.NotEqual(Guid.Empty, request.ModelId);
        Assert.NotEmpty(request.Justification);
    }

    [Fact]
    public void CreateSellDecisionResponse_ContainsRequiredFields()
    {
        var response = new CreateSellDecisionResponse
        {
            DecisionId = Guid.NewGuid(),
            ModelId = Guid.NewGuid(),
            Status = "PENDING",
            CorrelationId = Guid.NewGuid(),
            CreatedAt = DateTime.UtcNow
        };

        Assert.NotEqual(Guid.Empty, response.DecisionId);
        Assert.NotEmpty(response.Status);
    }

    [Fact]
    public void ExecuteSellDecisionRequest_ValidatesApprovalLinkage()
    {
        var request = new ExecuteSellDecisionRequest
        {
            ApprovalId = Guid.NewGuid(),
            ExecutionPrice = 150.25m,
            Quantity = 500,
            Justification = "Approved via VS-03"
        };

        Assert.NotEqual(Guid.Empty, request.ApprovalId);
        Assert.True(request.ExecutionPrice > 0);
        Assert.True(request.Quantity > 0);
    }
}
