// -----------------------------------------------------------------------------
// IAiCodeGuardService.cs
// Sprint: SPRINT_20260112_010_SCANNER_ai_code_guard_core
// Task: SCANNER-AIGUARD-002/006
// Description: AI Code Guard service interface for Scanner.
// -----------------------------------------------------------------------------

using System.Collections.Immutable;

namespace StellaOps.Scanner.AiCodeGuard;

/// <summary>
/// Service for AI Code Guard analysis.
/// </summary>
public interface IAiCodeGuardService
{
    /// <summary>
    /// Analyzes changed hunks for AI-generated code issues.
    /// </summary>
    /// <param name="request">Analysis request with hunks and options.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
    /// <returns>Analysis result with findings and verdict.</returns>
    Task<AiCodeGuardAnalysisResult> AnalyzeAsync(
        AiCodeGuardAnalysisRequest request,
        CancellationToken cancellationToken = default);
}

/// <summary>
/// Analysis request for AI Code Guard.
/// </summary>
public sealed record AiCodeGuardAnalysisRequest
{
    /// <summary>
    /// Repository URI.
    /// </summary>
    public required string RepositoryUri { get; init; }

    /// <summary>
    /// Commit SHA being analyzed.
    /// </summary>
    public required string CommitSha { get; init; }

    /// <summary>
    /// Branch name (optional).
    /// </summary>
    public string? Branch { get; init; }

    /// <summary>
    /// Base commit for diff comparison (optional, for PR analysis).
    /// </summary>
    public string? BaseCommitSha { get; init; }

    /// <summary>
    /// Changed hunks to analyze.
    /// </summary>
    public required IReadOnlyList<CodeHunk> Hunks { get; init; }

    /// <summary>
    /// Analysis timestamp (input, not wall-clock for determinism).
    /// </summary>
    public required DateTimeOffset AnalysisTimestamp { get; init; }

    /// <summary>
    /// Optional options override (uses defaults if null).
    /// </summary>
    public AiCodeGuardOptions? Options { get; init; }
}

/// <summary>
/// A code hunk to analyze.
/// </summary>
public sealed record CodeHunk
{
    /// <summary>
    /// File path relative to repository root.
    /// </summary>
    public required string FilePath { get; init; }

    /// <summary>
    /// Programming language (detected or specified).
    /// </summary>
    public required string Language { get; init; }

    /// <summary>
    /// Start line in the file (1-based).
    /// </summary>
    public required int StartLine { get; init; }

    /// <summary>
    /// End line in the file (1-based).
    /// </summary>
    public required int EndLine { get; init; }

    /// <summary>
    /// Hunk content (source code).
    /// </summary>
    public required string Content { get; init; }

    /// <summary>
    /// Whether this is new code (added) vs existing.
    /// </summary>
    public required bool IsNew { get; init; }

    /// <summary>
    /// SHA-256 hash of normalized content for deterministic hunk ID.
    /// </summary>
    public string? ContentHash { get; init; }
}

/// <summary>
/// AI Code Guard analysis result.
/// </summary>
public sealed record AiCodeGuardAnalysisResult
{
    /// <summary>
    /// Whether analysis completed successfully.
    /// </summary>
    public required bool Success { get; init; }

    /// <summary>
    /// Scanner configuration used.
    /// </summary>
    public required AiCodeGuardScannerConfigResult ScannerConfig { get; init; }

    /// <summary>
    /// Files analyzed.
    /// </summary>
    public required ImmutableList<AiCodeGuardFileResult> Files { get; init; }

    /// <summary>
    /// Detected findings.
    /// </summary>
    public required ImmutableList<AiCodeGuardFindingResult> Findings { get; init; }

    /// <summary>
    /// Overall verdict.
    /// </summary>
    public required AiCodeGuardVerdictResult Verdict { get; init; }

    /// <summary>
    /// Total lines analyzed.
    /// </summary>
    public required long TotalLinesAnalyzed { get; init; }

    /// <summary>
    /// Error message if Success is false.
    /// </summary>
    public string? Error { get; init; }

    /// <summary>
    /// Content digest for the analysis result (SHA-256).
    /// </summary>
    public string? ContentDigest { get; init; }
}

/// <summary>
/// Scanner configuration in result.
/// </summary>
public sealed record AiCodeGuardScannerConfigResult
{
    public required string ScannerVersion { get; init; }
    public required string ModelVersion { get; init; }
    public required double ConfidenceThreshold { get; init; }
    public required ImmutableList<string> EnabledCategories { get; init; }
    public ImmutableList<string>? RuleSets { get; init; }
}

/// <summary>
/// File analyzed in result.
/// </summary>
public sealed record AiCodeGuardFileResult
{
    public required string Path { get; init; }
    public required string Digest { get; init; }
    public required int LineCount { get; init; }
    public string? Language { get; init; }
}

/// <summary>
/// Finding in result.
/// </summary>
public sealed record AiCodeGuardFindingResult
{
    public required string Id { get; init; }
    public required string Category { get; init; }
    public required string Severity { get; init; }
    public required double Confidence { get; init; }
    public required string FilePath { get; init; }
    public required int StartLine { get; init; }
    public required int EndLine { get; init; }
    public int? StartColumn { get; init; }
    public int? EndColumn { get; init; }
    public string? Snippet { get; init; }
    public required string Description { get; init; }
    public required string RuleId { get; init; }
    public string? DetectionMethod { get; init; }
    public ImmutableList<string>? Indicators { get; init; }
    public double? PerplexityScore { get; init; }
    public ImmutableList<string>? PatternMatches { get; init; }
    public string? Remediation { get; init; }
}

/// <summary>
/// Verdict in result.
/// </summary>
public sealed record AiCodeGuardVerdictResult
{
    public required string Status { get; init; }
    public required int TotalFindings { get; init; }
    public required ImmutableDictionary<string, int> FindingsBySeverity { get; init; }
    public double? AiGeneratedPercentage { get; init; }
    public required string Message { get; init; }
    public string? Recommendation { get; init; }
}