using System.Text.Json.Serialization;

namespace StellaOps.BinaryIndex.Builders;

/// <summary>
/// A claim asserting a CVE verdict for a specific fingerprint.
/// Created when reproducible builds show a function was modified to fix a CVE.
/// </summary>
public sealed record FingerprintClaim
{
    /// <summary>
    /// Unique identifier for this claim.
    /// </summary>
    public Guid Id { get; init; }

    /// <summary>
    /// ID of the fingerprint this claim is about.
    /// </summary>
    public required Guid FingerprintId { get; init; }

    /// <summary>
    /// CVE identifier (e.g., "CVE-2023-12345").
    /// </summary>
    public required string CveId { get; init; }

    /// <summary>
    /// Verdict: whether this fingerprint is fixed, vulnerable, or unknown.
    /// </summary>
    public required ClaimVerdict Verdict { get; init; }

    /// <summary>
    /// Evidence supporting this claim.
    /// </summary>
    public required FingerprintClaimEvidence Evidence { get; init; }

    /// <summary>
    /// Hash of the DSSE attestation if signed.
    /// </summary>
    public string? AttestationDsseHash { get; init; }

    /// <summary>
    /// When this claim was created.
    /// </summary>
    public DateTimeOffset CreatedAt { get; init; } = DateTimeOffset.UtcNow;

    /// <summary>
    /// When this claim was last updated.
    /// </summary>
    public DateTimeOffset? UpdatedAt { get; init; }

    /// <summary>
    /// Source that generated this claim (e.g., "repro-builder-alpine").
    /// </summary>
    public string? Source { get; init; }

    /// <summary>
    /// Confidence in this claim (0.0-1.0).
    /// </summary>
    public decimal Confidence { get; init; } = 1.0m;
}

/// <summary>
/// Verdict for a fingerprint claim.
/// </summary>
[JsonConverter(typeof(JsonStringEnumConverter))]
public enum ClaimVerdict
{
    /// <summary>
    /// The fingerprint is from a binary that contains the CVE fix.
    /// </summary>
    Fixed,

    /// <summary>
    /// The fingerprint is from a binary that is vulnerable to the CVE.
    /// </summary>
    Vulnerable,

    /// <summary>
    /// Unable to determine fix status.
    /// </summary>
    Unknown
}

/// <summary>
/// Evidence supporting a fingerprint claim.
/// </summary>
public sealed record FingerprintClaimEvidence
{
    /// <summary>
    /// Git commit or patch reference that introduced the fix.
    /// </summary>
    public required string PatchCommit { get; init; }

    /// <summary>
    /// List of function names that changed between vulnerable and fixed versions.
    /// </summary>
    public required IReadOnlyList<string> ChangedFunctions { get; init; }

    /// <summary>
    /// Similarity scores for modified functions (function name -> score).
    /// </summary>
    public IReadOnlyDictionary<string, decimal>? FunctionSimilarities { get; init; }

    /// <summary>
    /// Reference to the vulnerable build artifacts.
    /// </summary>
    public string? VulnerableBuildRef { get; init; }

    /// <summary>
    /// Reference to the patched build artifacts.
    /// </summary>
    public string? PatchedBuildRef { get; init; }

    /// <summary>
    /// Source package name.
    /// </summary>
    public string? SourcePackage { get; init; }

    /// <summary>
    /// Vulnerable version string.
    /// </summary>
    public string? VulnerableVersion { get; init; }

    /// <summary>
    /// Patched version string.
    /// </summary>
    public string? PatchedVersion { get; init; }

    /// <summary>
    /// Distro and release this build was done for.
    /// </summary>
    public string? DistroRelease { get; init; }

    /// <summary>
    /// Builder image used for reproducible builds.
    /// </summary>
    public string? BuilderImage { get; init; }

    /// <summary>
    /// Timestamp of the vulnerable build.
    /// </summary>
    public DateTimeOffset? VulnerableBuildTimestamp { get; init; }

    /// <summary>
    /// Timestamp of the patched build.
    /// </summary>
    public DateTimeOffset? PatchedBuildTimestamp { get; init; }

    /// <summary>
    /// Diff statistics summary.
    /// </summary>
    public DiffStatistics? DiffStatistics { get; init; }
}

/// <summary>
/// Repository for managing fingerprint claims.
/// </summary>
public interface IFingerprintClaimRepository
{
    /// <summary>
    /// Creates a new fingerprint claim.
    /// </summary>
    /// <param name="claim">The claim to create.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>The created claim ID.</returns>
    Task<Guid> CreateClaimAsync(FingerprintClaim claim, CancellationToken ct = default);

    /// <summary>
    /// Creates multiple claims in a batch.
    /// </summary>
    /// <param name="claims">Claims to create.</param>
    /// <param name="ct">Cancellation token.</param>
    Task CreateClaimsBatchAsync(IEnumerable<FingerprintClaim> claims, CancellationToken ct = default);

    /// <summary>
    /// Gets a claim by ID.
    /// </summary>
    /// <param name="id">Claim ID.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>The claim if found.</returns>
    Task<FingerprintClaim?> GetClaimByIdAsync(Guid id, CancellationToken ct = default);

    /// <summary>
    /// Gets all claims for a specific fingerprint.
    /// </summary>
    /// <param name="fingerprintId">Fingerprint ID.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>List of claims for the fingerprint.</returns>
    Task<IReadOnlyList<FingerprintClaim>> GetClaimsByFingerprintAsync(
        Guid fingerprintId,
        CancellationToken ct = default);

    /// <summary>
    /// Gets all claims for a specific fingerprint hash.
    /// </summary>
    /// <param name="fingerprintHash">Fingerprint hash (hex-encoded).</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>List of claims for the fingerprint.</returns>
    Task<IReadOnlyList<FingerprintClaim>> GetClaimsByFingerprintHashAsync(
        string fingerprintHash,
        CancellationToken ct = default);

    /// <summary>
    /// Gets all claims for a specific CVE.
    /// </summary>
    /// <param name="cveId">CVE identifier.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>List of claims for the CVE.</returns>
    Task<IReadOnlyList<FingerprintClaim>> GetClaimsByCveAsync(
        string cveId,
        CancellationToken ct = default);

    /// <summary>
    /// Gets claims with a specific verdict.
    /// </summary>
    /// <param name="verdict">Verdict to filter by.</param>
    /// <param name="limit">Maximum results to return.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>List of claims with the verdict.</returns>
    Task<IReadOnlyList<FingerprintClaim>> GetClaimsByVerdictAsync(
        ClaimVerdict verdict,
        int limit = 100,
        CancellationToken ct = default);

    /// <summary>
    /// Updates an existing claim.
    /// </summary>
    /// <param name="claim">The updated claim.</param>
    /// <param name="ct">Cancellation token.</param>
    Task UpdateClaimAsync(FingerprintClaim claim, CancellationToken ct = default);

    /// <summary>
    /// Deletes a claim by ID.
    /// </summary>
    /// <param name="id">Claim ID.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>True if deleted, false if not found.</returns>
    Task<bool> DeleteClaimAsync(Guid id, CancellationToken ct = default);

    /// <summary>
    /// Checks if a claim already exists for a fingerprint+CVE combination.
    /// </summary>
    /// <param name="fingerprintId">Fingerprint ID.</param>
    /// <param name="cveId">CVE identifier.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>True if a claim exists.</returns>
    Task<bool> ClaimExistsAsync(Guid fingerprintId, string cveId, CancellationToken ct = default);
}

/// <summary>
/// Repository for managing function fingerprints (per-binary breakdown).
/// </summary>
public interface IFunctionFingerprintRepository
{
    /// <summary>
    /// Stores function fingerprints for a binary.
    /// </summary>
    /// <param name="binaryFingerprintId">Parent binary fingerprint ID.</param>
    /// <param name="functions">Function fingerprints to store.</param>
    /// <param name="ct">Cancellation token.</param>
    Task StoreFunctionsAsync(
        Guid binaryFingerprintId,
        IEnumerable<FunctionFingerprint> functions,
        CancellationToken ct = default);

    /// <summary>
    /// Gets all function fingerprints for a binary.
    /// </summary>
    /// <param name="binaryFingerprintId">Parent binary fingerprint ID.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>List of function fingerprints.</returns>
    Task<IReadOnlyList<FunctionFingerprint>> GetFunctionsByBinaryAsync(
        Guid binaryFingerprintId,
        CancellationToken ct = default);

    /// <summary>
    /// Searches for functions by name pattern.
    /// </summary>
    /// <param name="namePattern">Function name pattern (SQL LIKE).</param>
    /// <param name="limit">Maximum results.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Matching functions with their binary IDs.</returns>
    Task<IReadOnlyList<(Guid BinaryId, FunctionFingerprint Function)>> SearchFunctionsByNameAsync(
        string namePattern,
        int limit = 100,
        CancellationToken ct = default);

    /// <summary>
    /// Finds functions matching a specific basic block hash.
    /// </summary>
    /// <param name="basicBlockHash">Hash to search for.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Matching functions with their binary IDs.</returns>
    Task<IReadOnlyList<(Guid BinaryId, FunctionFingerprint Function)>> FindByBasicBlockHashAsync(
        byte[] basicBlockHash,
        CancellationToken ct = default);

    /// <summary>
    /// Deletes all function fingerprints for a binary.
    /// </summary>
    /// <param name="binaryFingerprintId">Parent binary fingerprint ID.</param>
    /// <param name="ct">Cancellation token.</param>
    Task DeleteFunctionsByBinaryAsync(Guid binaryFingerprintId, CancellationToken ct = default);
}