// <copyright file="IVexToSpdx3Mapper.cs" company="StellaOps">
// Copyright (c) StellaOps. Licensed under the BUSL-1.1.
// </copyright>

using StellaOps.Spdx3.Model;

namespace StellaOps.VexLens.Spdx3;

/// <summary>
/// Interface for mapping VEX consensus results to SPDX 3.0.1 Security profile documents.
/// Sprint: SPRINT_20260107_004_004 Task SP-005
/// </summary>
public interface IVexToSpdx3Mapper
{
    /// <summary>
    /// Maps a VEX consensus result to an SPDX 3.0.1 document with Security profile.
    /// </summary>
    /// <param name="consensus">The VEX consensus containing statements.</param>
    /// <param name="options">Mapping options.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
    /// <returns>The mapped SPDX 3.0.1 document.</returns>
    Task<Spdx3Document> MapConsensusAsync(
        VexConsensus consensus,
        VexToSpdx3Options options,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Maps individual VEX statements to SPDX 3.0.1 elements.
    /// </summary>
    /// <param name="statements">The VEX statements to map.</param>
    /// <param name="spdxIdPrefix">Prefix for generating SPDX IDs.</param>
    /// <returns>The mapped elements including vulnerabilities and assessment relationships.</returns>
    VexMappingResult MapStatements(
        IEnumerable<OpenVexStatement> statements,
        string spdxIdPrefix);
}

/// <summary>
/// Options for VEX to SPDX 3.0.1 mapping.
/// </summary>
public sealed record VexToSpdx3Options
{
    /// <summary>
    /// Gets the SPDX ID prefix for generated elements.
    /// </summary>
    public required string SpdxIdPrefix { get; init; }

    /// <summary>
    /// Gets the document name.
    /// </summary>
    public string? DocumentName { get; init; }

    /// <summary>
    /// Gets whether to include CVSS scores.
    /// </summary>
    public bool IncludeCvss { get; init; } = true;

    /// <summary>
    /// Gets whether to include EPSS scores.
    /// </summary>
    public bool IncludeEpss { get; init; } = true;

    /// <summary>
    /// Gets the tool identifier to include in creation info.
    /// </summary>
    public string ToolId { get; init; } = "StellaOps VexLens";

    /// <summary>
    /// Gets a filter for specific products (null = all).
    /// </summary>
    public IReadOnlyList<string>? ProductFilter { get; init; }

    /// <summary>
    /// Gets a filter for specific CVEs (null = all).
    /// </summary>
    public IReadOnlyList<string>? VulnerabilityFilter { get; init; }
}

/// <summary>
/// Result of mapping VEX statements to SPDX 3.0.1 elements.
/// </summary>
public sealed record VexMappingResult
{
    /// <summary>
    /// Gets the vulnerability elements.
    /// </summary>
    public required IReadOnlyList<Spdx3Element> Vulnerabilities { get; init; }

    /// <summary>
    /// Gets the VEX assessment relationships.
    /// </summary>
    public required IReadOnlyList<Spdx3Element> Assessments { get; init; }

    /// <summary>
    /// Gets the CVSS assessment relationships.
    /// </summary>
    public IReadOnlyList<Spdx3Element> CvssAssessments { get; init; } = Array.Empty<Spdx3Element>();

    /// <summary>
    /// Gets the EPSS assessment relationships.
    /// </summary>
    public IReadOnlyList<Spdx3Element> EpssAssessments { get; init; } = Array.Empty<Spdx3Element>();

    /// <summary>
    /// Gets all elements combined.
    /// </summary>
    public IEnumerable<Spdx3Element> AllElements =>
        Vulnerabilities
            .Concat(Assessments)
            .Concat(CvssAssessments)
            .Concat(EpssAssessments);
}

/// <summary>
/// Represents a VEX consensus containing multiple statements.
/// </summary>
public sealed record VexConsensus
{
    /// <summary>
    /// Gets the document identifier.
    /// </summary>
    public required string DocumentId { get; init; }

    /// <summary>
    /// Gets the document version.
    /// </summary>
    public string? Version { get; init; }

    /// <summary>
    /// Gets the statements in this consensus.
    /// </summary>
    public required IReadOnlyList<OpenVexStatement> Statements { get; init; }

    /// <summary>
    /// Gets the supplier/author.
    /// </summary>
    public string? Author { get; init; }

    /// <summary>
    /// Gets the timestamp.
    /// </summary>
    public DateTimeOffset? Timestamp { get; init; }
}

/// <summary>
/// Represents an OpenVEX statement.
/// </summary>
public sealed record OpenVexStatement
{
    /// <summary>
    /// Gets the vulnerability ID (e.g., CVE-2026-1234).
    /// </summary>
    public required string VulnerabilityId { get; init; }

    /// <summary>
    /// Gets the product ID (e.g., PURL).
    /// </summary>
    public required string ProductId { get; init; }

    /// <summary>
    /// Gets the VEX status.
    /// </summary>
    public required VexStatus Status { get; init; }

    /// <summary>
    /// Gets the justification for not_affected status.
    /// </summary>
    public VexJustification? Justification { get; init; }

    /// <summary>
    /// Gets the status notes.
    /// </summary>
    public string? StatusNotes { get; init; }

    /// <summary>
    /// Gets the impact statement.
    /// </summary>
    public string? ImpactStatement { get; init; }

    /// <summary>
    /// Gets the action statement for affected status.
    /// </summary>
    public string? ActionStatement { get; init; }

    /// <summary>
    /// Gets the action statement deadline.
    /// </summary>
    public DateTimeOffset? ActionStatementTime { get; init; }

    /// <summary>
    /// Gets the statement timestamp.
    /// </summary>
    public DateTimeOffset? Timestamp { get; init; }

    /// <summary>
    /// Gets the supplier/author.
    /// </summary>
    public string? Supplier { get; init; }

    /// <summary>
    /// Gets CVSS v3 data if available.
    /// </summary>
    public CvssV3Data? CvssV3 { get; init; }

    /// <summary>
    /// Gets EPSS data if available.
    /// </summary>
    public EpssData? Epss { get; init; }
}

/// <summary>
/// VEX status values.
/// </summary>
public enum VexStatus
{
    /// <summary>The product is affected by the vulnerability.</summary>
    Affected,

    /// <summary>The product is not affected by the vulnerability.</summary>
    NotAffected,

    /// <summary>The vulnerability is fixed in the product.</summary>
    Fixed,

    /// <summary>The status is under investigation.</summary>
    UnderInvestigation
}

/// <summary>
/// VEX justification values for not_affected status.
/// </summary>
public enum VexJustification
{
    /// <summary>The component is not present.</summary>
    ComponentNotPresent,

    /// <summary>The vulnerable code is not present.</summary>
    VulnerableCodeNotPresent,

    /// <summary>The vulnerable code cannot be controlled by an adversary.</summary>
    VulnerableCodeCannotBeControlledByAdversary,

    /// <summary>The vulnerable code is not in the execute path.</summary>
    VulnerableCodeNotInExecutePath,

    /// <summary>Inline mitigations already exist.</summary>
    InlineMitigationsAlreadyExist
}

/// <summary>
/// CVSS v3 scoring data.
/// Sprint: SPRINT_20260107_004_004 Task SP-007
/// </summary>
public sealed record CvssV3Data
{
    /// <summary>Gets the CVSS v3 base score (0.0-10.0).</summary>
    public decimal? BaseScore { get; init; }

    /// <summary>Gets the CVSS v3 vector string.</summary>
    public string? VectorString { get; init; }

    /// <summary>Gets the temporal score if available.</summary>
    public decimal? TemporalScore { get; init; }

    /// <summary>Gets the environmental score if available.</summary>
    public decimal? EnvironmentalScore { get; init; }

    /// <summary>Gets when the score was published.</summary>
    public DateTimeOffset? PublishedTime { get; init; }

    /// <summary>Gets when the score was modified.</summary>
    public DateTimeOffset? ModifiedTime { get; init; }

    /// <summary>Gets the source of the CVSS data.</summary>
    public string? Source { get; init; }
}

/// <summary>
/// EPSS (Exploit Prediction Scoring System) data.
/// Sprint: SPRINT_20260107_004_004 Task SP-007
/// </summary>
public sealed record EpssData
{
    /// <summary>Gets the EPSS probability (0.0-1.0).</summary>
    public decimal? Probability { get; init; }

    /// <summary>Gets the EPSS percentile (0.0-1.0).</summary>
    public decimal? Percentile { get; init; }

    /// <summary>Gets the date of the EPSS score.</summary>
    public DateTimeOffset? ScoreDate { get; init; }
}