// Licensed under AGPL-3.0-or-later. Copyright (C) 2026 StellaOps Contributors.
// Sprint: SPRINT_20260110_012_007_RISK
// Task: FCR-009 - Integration Tests

using System.Collections.Immutable;
using FluentAssertions;
using Microsoft.Extensions.Caching.Memory;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Options;
using StellaOps.RiskEngine.Core.Contracts;
using StellaOps.RiskEngine.Core.Providers.FixChain;
using Xunit;

namespace StellaOps.RiskEngine.Tests;

[Trait("Category", "Integration")]
public sealed class FixChainRiskIntegrationTests
{
    private readonly FixChainRiskOptions _options;
    private readonly InMemoryFixChainAttestationClient _attestationClient;
    private readonly FixChainRiskProvider _provider;

    public FixChainRiskIntegrationTests()
    {
        _options = new FixChainRiskOptions
        {
            Enabled = true,
            FixedReduction = 0.90,
            PartialReduction = 0.50,
            MinConfidenceThreshold = 0.60m
        };

        _attestationClient = new InMemoryFixChainAttestationClient();
        _provider = new FixChainRiskProvider(
            _options,
            _attestationClient,
            NullLogger<FixChainRiskProvider>.Instance);
    }

    [Fact]
    public async Task FullWorkflow_FixedVerdict_ReducesRisk()
    {
        // Arrange
        var cveId = "CVE-2024-12345";
        var binarySha256 = new string('a', 64);
        var attestation = new FixChainAttestationData
        {
            ContentDigest = "sha256:abc123",
            CveId = cveId,
            ComponentPurl = "pkg:deb/debian/openssl@3.0.11",
            BinarySha256 = binarySha256,
            Verdict = new FixChainVerdictData
            {
                Status = "fixed",
                Confidence = 0.97m,
                Rationale = ["3 vulnerable functions removed", "All paths eliminated"]
            },
            GoldenSetId = "gs-openssl-0727",
            VerifiedAt = DateTimeOffset.UtcNow
        };
        _attestationClient.AddAttestation(cveId, binarySha256, attestation);

        // Act
        var status = await _provider.GetFixStatusAsync(cveId, binarySha256);

        // Assert
        status.Should().NotBeNull();
        status!.Verdict.Should().Be("fixed");
        status.Confidence.Should().Be(0.97m);
        status.Rationale.Should().HaveCount(2);
        status.GoldenSetId.Should().Be("gs-openssl-0727");

        // Verify risk adjustment
        var adjustment = _provider.ComputeRiskAdjustment(status);
        adjustment.Should().BeLessThan(0.3); // Significant reduction
    }

    [Fact]
    public async Task FullWorkflow_CreateRiskFactor_ProducesValidFactor()
    {
        // Arrange
        var cveId = "CVE-2024-67890";
        var binarySha256 = new string('b', 64);
        var attestation = new FixChainAttestationData
        {
            ContentDigest = "sha256:def456",
            CveId = cveId,
            ComponentPurl = "pkg:npm/lodash@4.17.21",
            BinarySha256 = binarySha256,
            Verdict = new FixChainVerdictData
            {
                Status = "partial",
                Confidence = 0.75m,
                Rationale = ["2 paths eliminated", "1 path remaining"]
            },
            VerifiedAt = DateTimeOffset.UtcNow
        };
        _attestationClient.AddAttestation(cveId, binarySha256, attestation);

        // Act
        var status = await _provider.GetFixStatusAsync(cveId, binarySha256);
        var factor = _provider.CreateRiskFactor(status!);

        // Assert
        factor.Verdict.Should().Be(FixChainVerdictStatus.Partial);
        factor.Confidence.Should().Be(0.75m);
        factor.RiskModifier.Should().BeLessThan(0);
        factor.AttestationRef.Should().StartWith("fixchain://");
        factor.Rationale.Should().HaveCount(2);
    }

    [Fact]
    public async Task FullWorkflow_DisplayModel_HasCorrectValues()
    {
        // Arrange
        var cveId = "CVE-2024-99999";
        var binarySha256 = new string('c', 64);
        var attestation = new FixChainAttestationData
        {
            ContentDigest = "sha256:ghi789",
            CveId = cveId,
            ComponentPurl = "pkg:maven/org.example/lib@1.0.0",
            BinarySha256 = binarySha256,
            Verdict = new FixChainVerdictData
            {
                Status = "fixed",
                Confidence = 0.95m,
                Rationale = ["Fix verified"]
            },
            GoldenSetId = "gs-example",
            VerifiedAt = DateTimeOffset.UtcNow
        };
        _attestationClient.AddAttestation(cveId, binarySha256, attestation);

        // Act
        var status = await _provider.GetFixStatusAsync(cveId, binarySha256);
        var factor = _provider.CreateRiskFactor(status!);
        var display = factor.ToDisplay();

        // Assert
        display.Label.Should().Be("Fix Verification");
        display.Value.Should().Contain("Fixed");
        display.Value.Should().Contain("95");
        display.ImpactDirection.Should().Be("decrease");
        display.EvidenceRef.Should().Contain("fixchain://");
        display.Details.Should().ContainKey("golden_set_id");
    }

    [Fact]
    public async Task FullWorkflow_Badge_HasCorrectStyle()
    {
        // Arrange
        var cveId = "CVE-2024-11111";
        var binarySha256 = new string('d', 64);
        var attestation = new FixChainAttestationData
        {
            ContentDigest = "sha256:jkl012",
            CveId = cveId,
            ComponentPurl = "pkg:pypi/requests@2.28.0",
            BinarySha256 = binarySha256,
            Verdict = new FixChainVerdictData
            {
                Status = "inconclusive",
                Confidence = 0.45m,
                Rationale = ["Could not determine"]
            },
            VerifiedAt = DateTimeOffset.UtcNow
        };
        _attestationClient.AddAttestation(cveId, binarySha256, attestation);

        // Act
        var status = await _provider.GetFixStatusAsync(cveId, binarySha256);
        var factor = _provider.CreateRiskFactor(status!);
        var badge = factor.ToBadge();

        // Assert
        badge.Status.Should().Be("Inconclusive");
        badge.Color.Should().Be("gray");
    }

    [Fact]
    public async Task FullWorkflow_MultipleAttestations_SameComponent()
    {
        // Arrange - add multiple CVE attestations for same component
        var binarySha256 = new string('e', 64);
        var cveIds = new[] { "CVE-2024-001", "CVE-2024-002", "CVE-2024-003" };

        foreach (var cveId in cveIds)
        {
            _attestationClient.AddAttestation(cveId, binarySha256, new FixChainAttestationData
            {
                ContentDigest = $"sha256:{cveId}",
                CveId = cveId,
                ComponentPurl = "pkg:deb/debian/openssl@3.0.11",
                BinarySha256 = binarySha256,
                Verdict = new FixChainVerdictData
                {
                    Status = "fixed",
                    Confidence = 0.95m,
                    Rationale = [$"Fix for {cveId}"]
                },
                VerifiedAt = DateTimeOffset.UtcNow
            });
        }

        // Act & Assert - each CVE can be queried individually
        foreach (var cveId in cveIds)
        {
            var status = await _provider.GetFixStatusAsync(cveId, binarySha256);
            status.Should().NotBeNull();
            status!.Verdict.Should().Be("fixed");
        }
    }

    [Fact]
    public async Task FullWorkflow_ScoreRequest_AppliesAdjustment()
    {
        // Arrange
        var signals = new Dictionary<string, double>
        {
            [FixChainRiskProvider.SignalFixConfidence] = 0.90,
            [FixChainRiskProvider.SignalFixStatus] = FixChainRiskProvider.EncodeStatus("fixed")
        };
        var request = new ScoreRequest("fixchain", "test-subject", signals);

        // Act
        var score = await _provider.ScoreAsync(request, CancellationToken.None);

        // Assert
        score.Should().BeLessThan(0.5); // Significant reduction applied
    }

    [Fact]
    public async Task FullWorkflow_DisabledProvider_NoAdjustment()
    {
        // Arrange
        var disabledOptions = new FixChainRiskOptions { Enabled = false };
        var disabledProvider = new FixChainRiskProvider(disabledOptions);

        var signals = new Dictionary<string, double>
        {
            [FixChainRiskProvider.SignalFixConfidence] = 1.0,
            [FixChainRiskProvider.SignalFixStatus] = FixChainRiskProvider.EncodeStatus("fixed")
        };
        var request = new ScoreRequest("fixchain", "test-subject", signals);

        // Act
        var score = await disabledProvider.ScoreAsync(request, CancellationToken.None);

        // Assert
        score.Should().Be(1.0); // No adjustment when disabled
    }

    [Fact]
    public async Task FullWorkflow_NoAttestation_ReturnsNull()
    {
        // Act
        var status = await _provider.GetFixStatusAsync(
            "CVE-NONEXISTENT",
            new string('x', 64));

        // Assert
        status.Should().BeNull();
    }

    [Fact]
    public async Task FullWorkflow_GetForComponent_ReturnsMultiple()
    {
        // Arrange
        var componentPurl = "pkg:deb/debian/test@1.0.0";
        var cves = new[] { "CVE-2024-A", "CVE-2024-B" };

        foreach (var cveId in cves)
        {
            _attestationClient.AddAttestation(cveId, new string('f', 64), new FixChainAttestationData
            {
                ContentDigest = $"sha256:{cveId}",
                CveId = cveId,
                ComponentPurl = componentPurl,
                BinarySha256 = new string('f', 64),
                Verdict = new FixChainVerdictData
                {
                    Status = "fixed",
                    Confidence = 0.90m,
                    Rationale = []
                },
                VerifiedAt = DateTimeOffset.UtcNow
            });
        }

        // Act
        var attestations = await _attestationClient.GetForComponentAsync(componentPurl);

        // Assert
        attestations.Should().HaveCount(2);
    }
}

/// <summary>
/// In-memory attestation client for testing.
/// </summary>
internal sealed class InMemoryFixChainAttestationClient : IFixChainAttestationClient
{
    private readonly Dictionary<string, FixChainAttestationData> _store = new();
    private readonly Dictionary<string, List<FixChainAttestationData>> _byComponent = new();

    public void AddAttestation(string cveId, string binarySha256, FixChainAttestationData attestation)
    {
        var key = $"{cveId}:{binarySha256}";
        _store[key] = attestation;

        if (!string.IsNullOrEmpty(attestation.ComponentPurl))
        {
            if (!_byComponent.TryGetValue(attestation.ComponentPurl, out var list))
            {
                list = [];
                _byComponent[attestation.ComponentPurl] = list;
            }
            list.Add(attestation);
        }
    }

    public Task<FixChainAttestationData?> GetFixChainAsync(
        string cveId,
        string binarySha256,
        string? componentPurl = null,
        CancellationToken ct = default)
    {
        var key = $"{cveId}:{binarySha256}";
        return Task.FromResult(_store.GetValueOrDefault(key));
    }

    public Task<ImmutableArray<FixChainAttestationData>> GetForComponentAsync(
        string componentPurl,
        CancellationToken ct = default)
    {
        if (_byComponent.TryGetValue(componentPurl, out var list))
        {
            return Task.FromResult(list.ToImmutableArray());
        }
        return Task.FromResult(ImmutableArray<FixChainAttestationData>.Empty);
    }
}