using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Options;
using StellaOps.Attestor.Core.Rekor;
using StellaOps.Attestor.Core.Submission;
using StellaOps.Cryptography;
using StellaOps.Scanner.ProofSpine;
using StellaOps.Scanner.ProofSpine.Options;
using StellaOps.Scanner.Reachability.Attestation;
using Xunit;

using StellaOps.TestKit;
namespace StellaOps.Scanner.Reachability.Tests;

public sealed class ReachabilityWitnessPublisherIntegrationTests
{
    private static CancellationToken TestCancellationToken => TestContext.Current.CancellationToken;
    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task PublishAsync_WhenStoreInCasEnabled_StoresGraphAndEnvelopeInCas()
    {
        var options = Options.Create(new ReachabilityWitnessOptions
        {
            Enabled = true,
            StoreInCas = true,
            PublishToRekor = false,
        });

        var cas = new FakeFileContentAddressableStore();
        var cryptoHash = CryptoHashFactory.CreateDefault();
        var publisher = new ReachabilityWitnessPublisher(
            options,
            cryptoHash,
            NullLogger<ReachabilityWitnessPublisher>.Instance,
            cas: cas);

        var graph = CreateTestGraph();
        var graphBytes = System.Text.Encoding.UTF8.GetBytes("{\"schema\":\"richgraph-v1\",\"nodes\":[],\"edges\":[]}");

        var result = await publisher.PublishAsync(
            graph,
            graphBytes,
            graphHash: "blake3:abc123",
            subjectDigest: "sha256:def456",
            cancellationToken: TestCancellationToken);

        Assert.Equal("cas://reachability/graphs/abc123", result.CasUri);
        Assert.Equal(graphBytes, cas.GetBytes("abc123"));
        Assert.NotNull(cas.GetBytes("abc123.dsse"));
        Assert.NotEmpty(result.DsseEnvelopeBytes);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task PublishAsync_WhenRekorEnabled_SubmitsDsseEnvelope()
    {
        var rekor = new CapturingRekorClient();
        var signer = CreateDeterministicSigner(keyId: "reachability-test-key");
        var cryptoProfile = new TestCryptoProfile("reachability-test-key", "hs256");

        var options = Options.Create(new ReachabilityWitnessOptions
        {
            Enabled = true,
            StoreInCas = false,
            PublishToRekor = true,
            RekorUrl = new Uri("https://rekor.test"),
            RekorBackendName = "primary",
            SigningKeyId = "reachability-test-key",
            Tier = AttestationTier.Standard
        });

        var cryptoHash = CryptoHashFactory.CreateDefault();
        var publisher = new ReachabilityWitnessPublisher(
            options,
            cryptoHash,
            NullLogger<ReachabilityWitnessPublisher>.Instance,
            dsseSigningService: signer,
            cryptoProfile: cryptoProfile,
            rekorClient: rekor);

        var graph = CreateTestGraph();
        var result = await publisher.PublishAsync(
            graph,
            graphBytes: Array.Empty<byte>(),
            graphHash: "blake3:abc123",
            subjectDigest: "sha256:def456",
            cancellationToken: TestCancellationToken);

        Assert.NotNull(rekor.LastRequest);
        Assert.NotNull(rekor.LastBackend);
        Assert.Equal("primary", rekor.LastBackend!.Name);
        Assert.Equal(new Uri("https://rekor.test"), rekor.LastBackend.Url);

        var request = rekor.LastRequest!;
        Assert.Equal("application/vnd.in-toto+json", request.Bundle.Dsse.PayloadType);
        Assert.False(string.IsNullOrWhiteSpace(request.Bundle.Dsse.PayloadBase64));
        Assert.NotEmpty(request.Bundle.Dsse.Signatures);
        Assert.Equal("reachability-test-key", request.Bundle.Dsse.Signatures[0].KeyId);
        Assert.False(string.IsNullOrWhiteSpace(request.Meta.BundleSha256));

        Assert.Equal(1234, result.RekorLogIndex);
        Assert.Equal("rekor-uuid-1234", result.RekorLogId);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task PublishAsync_WhenAirGapped_SkipsRekorSubmission()
    {
        var rekor = new CapturingRekorClient();

        var options = Options.Create(new ReachabilityWitnessOptions
        {
            Enabled = true,
            StoreInCas = false,
            PublishToRekor = true,
            RekorUrl = new Uri("https://rekor.test"),
            Tier = AttestationTier.AirGapped,
        });

        var cryptoHash = CryptoHashFactory.CreateDefault();
        var publisher = new ReachabilityWitnessPublisher(
            options,
            cryptoHash,
            NullLogger<ReachabilityWitnessPublisher>.Instance,
            rekorClient: rekor);

        var graph = CreateTestGraph();
        var result = await publisher.PublishAsync(
            graph,
            graphBytes: Array.Empty<byte>(),
            graphHash: "blake3:abc123",
            subjectDigest: "sha256:def456",
            cancellationToken: TestCancellationToken);

        Assert.Null(rekor.LastRequest);
        Assert.Null(result.RekorLogIndex);
        Assert.Null(result.RekorLogId);
    }

    private static RichGraph CreateTestGraph()
    {
        return new RichGraph(
            Schema: "richgraph-v1",
            Analyzer: new RichGraphAnalyzer("test-analyzer", "1.0.0", null),
            Nodes: new[]
            {
                new RichGraphNode("n1", "sym:dotnet:A", null, null, "dotnet", "method", "A", null, null, null, null),
                new RichGraphNode("n2", "sym:dotnet:B", null, null, "dotnet", "sink", "B", null, null, null, null)
            },
            Edges: new[]
            {
                new RichGraphEdge("n1", "n2", "call", null, null, null, 1.0, null)
            },
            Roots: null!);
    }

    private static IDsseSigningService CreateDeterministicSigner(string keyId)
    {
        var options = Options.Create(new ProofSpineDsseSigningOptions
        {
            Mode = "hash",
            KeyId = keyId,
            Algorithm = "hs256",
            AllowDeterministicFallback = true,
        });

        return new HmacDsseSigningService(
            options,
            DefaultCryptoHmac.CreateForTests(),
            DefaultCryptoHash.CreateForTests());
    }

    private sealed record TestCryptoProfile(string KeyId, string Algorithm) : ICryptoProfile;

    private sealed class CapturingRekorClient : IRekorClient
    {
        public AttestorSubmissionRequest? LastRequest { get; private set; }

        public RekorBackend? LastBackend { get; private set; }

        public Task<RekorSubmissionResponse> SubmitAsync(AttestorSubmissionRequest request, RekorBackend backend, CancellationToken cancellationToken = default)
        {
            LastRequest = request;
            LastBackend = backend;

            return Task.FromResult(new RekorSubmissionResponse
            {
                Uuid = "rekor-uuid-1234",
                Index = 1234,
                LogUrl = backend.Url.ToString(),
                Status = "included",
                Proof = null
            });
        }

        public Task<RekorProofResponse?> GetProofAsync(string rekorUuid, RekorBackend backend, CancellationToken cancellationToken = default)
            => Task.FromResult<RekorProofResponse?>(null);

        public Task<RekorInclusionVerificationResult> VerifyInclusionAsync(string rekorUuid, byte[] payloadDigest, RekorBackend backend, CancellationToken cancellationToken = default)
            => Task.FromResult(RekorInclusionVerificationResult.Failure("not_implemented"));
    }
}