// -----------------------------------------------------------------------------
// AiCodeGuardSignalContextExtensions.cs
// Sprint: SPRINT_20260112_010_POLICY_ai_code_guard_policy
// Task: POLICY-AIGUARD-001/005 - AI Code Guard signal context integration
// -----------------------------------------------------------------------------

using StellaOps.Policy.AiCodeGuard;

namespace StellaOps.PolicyDsl;

/// <summary>
/// Extension methods for integrating AI Code Guard evidence with PolicyDsl SignalContext.
/// </summary>
public static class AiCodeGuardSignalContextExtensions
{
    /// <summary>
    /// Adds AI Code Guard evidence signals to the signal context.
    /// </summary>
    /// <param name="context">The signal context.</param>
    /// <param name="evidenceContext">The AI Code Guard evidence context.</param>
    /// <returns>The signal context for chaining.</returns>
    public static SignalContext WithAiCodeGuardEvidence(
        this SignalContext context,
        AiCodeGuardEvidenceContext evidenceContext)
    {
        ArgumentNullException.ThrowIfNull(context);
        ArgumentNullException.ThrowIfNull(evidenceContext);

        // Add flat signals
        var signals = AiCodeGuardSignalBinder.BindToSignals(evidenceContext);
        foreach (var (name, value) in signals)
        {
            context.SetSignal(name, value);
        }

        // Add nested object for member access (guard.severity.high, etc.)
        var nested = AiCodeGuardSignalBinder.BindToNestedObject(evidenceContext);
        context.SetSignal("guard", nested);

        // Add policy recommendation
        context.SetSignal("guard.recommendation", AiCodeGuardSignalBinder.GetRecommendation(evidenceContext));

        // Add explain trace for deterministic auditing
        context.SetSignal("guard.explain_trace", AiCodeGuardSignalBinder.CreateExplainTrace(evidenceContext));

        return context;
    }

    /// <summary>
    /// Adds AI Code Guard evidence signals to the signal context builder.
    /// </summary>
    /// <param name="builder">The signal context builder.</param>
    /// <param name="evidenceContext">The AI Code Guard evidence context.</param>
    /// <returns>The builder for chaining.</returns>
    public static SignalContextBuilder WithAiCodeGuardEvidence(
        this SignalContextBuilder builder,
        AiCodeGuardEvidenceContext evidenceContext)
    {
        ArgumentNullException.ThrowIfNull(builder);
        ArgumentNullException.ThrowIfNull(evidenceContext);

        // Add flat signals
        var signals = AiCodeGuardSignalBinder.BindToSignals(evidenceContext);
        foreach (var (name, value) in signals)
        {
            builder.WithSignal(name, value);
        }

        // Add nested object for member access
        var nested = AiCodeGuardSignalBinder.BindToNestedObject(evidenceContext);
        builder.WithSignal("guard", nested);

        // Add policy recommendation
        builder.WithSignal("guard.recommendation", AiCodeGuardSignalBinder.GetRecommendation(evidenceContext));

        // Add explain trace
        builder.WithSignal("guard.explain_trace", AiCodeGuardSignalBinder.CreateExplainTrace(evidenceContext));

        return builder;
    }

    /// <summary>
    /// Adds AI Code Guard evidence signals from a provider.
    /// </summary>
    /// <param name="builder">The signal context builder.</param>
    /// <param name="provider">The AI Code Guard evidence provider.</param>
    /// <returns>The builder for chaining.</returns>
    public static SignalContextBuilder WithAiCodeGuardEvidence(
        this SignalContextBuilder builder,
        IAiCodeGuardEvidenceProvider provider)
    {
        ArgumentNullException.ThrowIfNull(builder);
        ArgumentNullException.ThrowIfNull(provider);

        var context = new AiCodeGuardEvidenceContext(provider);
        return builder.WithAiCodeGuardEvidence(context);
    }

    /// <summary>
    /// Creates a signal context builder with AI Code Guard evidence.
    /// </summary>
    /// <param name="evidenceContext">The AI Code Guard evidence context.</param>
    /// <returns>A new builder with guard signals.</returns>
    public static SignalContextBuilder CreateBuilderWithGuardEvidence(AiCodeGuardEvidenceContext evidenceContext)
    {
        return SignalContext.Builder().WithAiCodeGuardEvidence(evidenceContext);
    }

    /// <summary>
    /// Creates a signal context with AI Code Guard evidence.
    /// </summary>
    /// <param name="evidenceContext">The AI Code Guard evidence context.</param>
    /// <returns>A new signal context with guard signals.</returns>
    public static SignalContext CreateContextWithGuardEvidence(AiCodeGuardEvidenceContext evidenceContext)
    {
        return CreateBuilderWithGuardEvidence(evidenceContext).Build();
    }

    /// <summary>
    /// Adds simplified AI Code Guard result signals for quick checks.
    /// This is useful when you have analysis results but not a full evidence provider.
    /// </summary>
    /// <param name="builder">The signal context builder.</param>
    /// <param name="status">The verdict status.</param>
    /// <param name="totalFindings">Total finding count.</param>
    /// <param name="criticalCount">Critical severity count.</param>
    /// <param name="highCount">High severity count.</param>
    /// <param name="mediumCount">Medium severity count.</param>
    /// <param name="aiPercentage">Optional AI-generated percentage.</param>
    /// <returns>The builder for chaining.</returns>
    public static SignalContextBuilder WithAiCodeGuardResult(
        this SignalContextBuilder builder,
        string status,
        int totalFindings,
        int criticalCount = 0,
        int highCount = 0,
        int mediumCount = 0,
        double? aiPercentage = null)
    {
        ArgumentNullException.ThrowIfNull(builder);

        builder.WithSignal("guard.verdict", status.ToLowerInvariant());
        builder.WithSignal("guard.count", totalFindings);
        builder.WithSignal("guard.has_finding", totalFindings > 0);
        builder.WithSignal("guard.severity.critical", criticalCount > 0);
        builder.WithSignal("guard.severity.critical_count", criticalCount);
        builder.WithSignal("guard.severity.high", highCount > 0);
        builder.WithSignal("guard.severity.high_count", highCount);
        builder.WithSignal("guard.severity.medium", mediumCount > 0);
        builder.WithSignal("guard.severity.medium_count", mediumCount);
        builder.WithSignal("guard.ai_percentage", aiPercentage);

        // Derive recommendation
        var recommendation = status.ToLowerInvariant() switch
        {
            "pass" => "allow",
            "passwithwarnings" or "pass_with_warnings" => "review",
            "fail" => "block",
            "error" => "block",
            _ => "review"
        };
        builder.WithSignal("guard.recommendation", recommendation);

        return builder;
    }
}