// -----------------------------------------------------------------------------
// AuditPackExportServiceTests.cs
// Sprint: SPRINT_1227_0005_0003_FE_copy_audit_export
// Task: T10 — Unit tests for AuditPackExportService
// -----------------------------------------------------------------------------

namespace StellaOps.AuditPack.Tests;

using StellaOps.AuditPack.Models;
using StellaOps.AuditPack.Services;
using System.IO.Compression;
using System.Text.Json;

[Trait("Category", "Unit")]
public class AuditPackExportServiceTests
{
    private readonly AuditPackExportService _service;

    public AuditPackExportServiceTests()
    {
        _service = new AuditPackExportService(
            new MockAuditBundleWriter(),
            null);
    }

    [Fact]
    public async Task ExportAsync_Zip_CreatesValidZipArchive()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-123",
            Format = ExportFormat.Zip,
            Segments = [ExportSegment.Sbom, ExportSegment.Match],
            IncludeAttestations = true,
            IncludeProofChain = false,
            Filename = "test-export"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeTrue();
        result.ContentType.Should().Be("application/zip");
        result.Filename.Should().Be("test-export.zip");
        result.Data.Should().NotBeNull();
        result.SizeBytes.Should().BeGreaterThan(0);

        // Verify ZIP structure
        using var memoryStream = new MemoryStream(result.Data!);
        using var archive = new ZipArchive(memoryStream, ZipArchiveMode.Read);
        archive.Entries.Should().Contain(e => e.FullName == "manifest.json");
    }

    [Fact]
    public async Task ExportAsync_Json_CreatesSingleJsonFile()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-456",
            Format = ExportFormat.Json,
            Segments = [ExportSegment.Sbom],
            IncludeAttestations = false,
            IncludeProofChain = false,
            Filename = "test-json"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeTrue();
        result.ContentType.Should().Be("application/json");
        result.Filename.Should().Be("test-json.json");

        // Verify JSON structure
        using var jsonDoc = JsonDocument.Parse(result.Data!);
        var root = jsonDoc.RootElement;
        root.TryGetProperty("scanId", out var scanIdProp).Should().BeTrue();
        scanIdProp.GetString().Should().Be("scan-456");
        root.TryGetProperty("segments", out _).Should().BeTrue();
    }

    [Fact]
    public async Task ExportAsync_Dsse_CreatesDsseEnvelope()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-789",
            Format = ExportFormat.Dsse,
            Segments = [ExportSegment.Policy],
            IncludeAttestations = true,
            IncludeProofChain = true,
            Filename = "test-dsse"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeTrue();
        result.ContentType.Should().Be("application/vnd.dsse+json");
        result.Filename.Should().Be("test-dsse.dsse.json");

        // Verify DSSE structure
        using var jsonDoc = JsonDocument.Parse(result.Data!);
        var root = jsonDoc.RootElement;
        root.TryGetProperty("payloadType", out var payloadType).Should().BeTrue();
        payloadType.GetString().Should().Be("application/vnd.stellaops.audit-pack+json");
        root.TryGetProperty("payload", out _).Should().BeTrue();
        root.TryGetProperty("signatures", out _).Should().BeTrue();
    }

    [Fact]
    public async Task ExportAsync_AllSegments_IncludesAllInZip()
    {
        // Arrange
        var allSegments = new[]
        {
            ExportSegment.Sbom,
            ExportSegment.Match,
            ExportSegment.Reachability,
            ExportSegment.Guards,
            ExportSegment.Runtime,
            ExportSegment.Policy
        };

        var request = new ExportRequest
        {
            ScanId = "scan-full",
            Format = ExportFormat.Zip,
            Segments = allSegments,
            IncludeAttestations = true,
            IncludeProofChain = true,
            Filename = "full-export"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeTrue();

        using var memoryStream = new MemoryStream(result.Data!);
        using var archive = new ZipArchive(memoryStream, ZipArchiveMode.Read);

        // Should have manifest + 6 segments + attestations + proof chain
        archive.Entries.Count.Should().BeGreaterThanOrEqualTo(3);
    }

    [Fact]
    public async Task ExportAsync_EmptySegments_StillCreatesValidExport()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-empty",
            Format = ExportFormat.Json,
            Segments = [],
            IncludeAttestations = false,
            IncludeProofChain = false,
            Filename = "empty-export"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeTrue();
        result.Data.Should().NotBeNull();
    }

    [Fact]
    public async Task ExportAsync_UnsupportedFormat_ReturnsFailed()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-fail",
            Format = (ExportFormat)999, // Invalid format
            Segments = [ExportSegment.Sbom],
            IncludeAttestations = false,
            IncludeProofChain = false,
            Filename = "fail-export"
        };

        // Act
        var result = await _service.ExportAsync(request);

        // Assert
        result.Success.Should().BeFalse();
        result.Error.Should().Contain("Unsupported");
    }

    [Fact]
    public async Task ExportAsync_CancellationRequested_ThrowsOperationCanceled()
    {
        // Arrange
        var request = new ExportRequest
        {
            ScanId = "scan-cancel",
            Format = ExportFormat.Zip,
            Segments = [ExportSegment.Sbom],
            IncludeAttestations = false,
            IncludeProofChain = false,
            Filename = "cancel-export"
        };

        var cts = new CancellationTokenSource();
        cts.Cancel();

        // Act & Assert
        await Assert.ThrowsAsync<OperationCanceledException>(
            () => _service.ExportAsync(request, cts.Token));
    }

    // Mock implementation for testing
    private class MockAuditBundleWriter : IAuditBundleWriter
    {
        public Task<AuditBundleWriteResult> WriteAsync(
            AuditBundleWriteRequest request,
            CancellationToken cancellationToken = default)
        {
            return Task.FromResult(new AuditBundleWriteResult { Success = true });
        }
    }
}