// -----------------------------------------------------------------------------
// K8sBoundaryExtractorTests.cs
// Sprint: SPRINT_3800_0002_0002_boundary_k8s
// Description: Unit tests for K8sBoundaryExtractor.
// -----------------------------------------------------------------------------

using Microsoft.Extensions.Logging.Abstractions;
using StellaOps.Scanner.Reachability.Boundary;
using StellaOps.Scanner.Reachability.Gates;
using Xunit;

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

public class K8sBoundaryExtractorTests
{
    private readonly K8sBoundaryExtractor _extractor;

    public K8sBoundaryExtractorTests()
    {
        _extractor = new K8sBoundaryExtractor(
            NullLogger<K8sBoundaryExtractor>.Instance);
    }

    #region Priority and CanHandle

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Priority_Returns200_HigherThanRichGraphExtractor()
    {
        Assert.Equal(200, _extractor.Priority);
    }

    [Trait("Category", TestCategories.Unit)]
        [Theory]
    [InlineData("k8s", true)]
    [InlineData("K8S", true)]
    [InlineData("kubernetes", true)]
    [InlineData("Kubernetes", true)]
    [InlineData("static", false)]
    [InlineData("runtime", false)]
    public void CanHandle_WithSource_ReturnsExpected(string source, bool expected)
    {
        var context = BoundaryExtractionContext.Empty with { Source = source };
        Assert.Equal(expected, _extractor.CanHandle(context));
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void CanHandle_WithK8sAnnotations_ReturnsTrue()
    {
        var context = BoundaryExtractionContext.Empty with
        {
            Annotations = new Dictionary<string, string>
            {
                ["kubernetes.io/ingress.class"] = "nginx"
            }
        };

        Assert.True(_extractor.CanHandle(context));
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void CanHandle_WithIngressAnnotation_ReturnsTrue()
    {
        var context = BoundaryExtractionContext.Empty with
        {
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/rewrite-target"] = "/"
            }
        };

        Assert.True(_extractor.CanHandle(context));
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void CanHandle_WithEmptyAnnotations_ReturnsFalse()
    {
        var context = BoundaryExtractionContext.Empty;
        Assert.False(_extractor.CanHandle(context));
    }

    #endregion

    #region Extract - Exposure Detection

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithInternetFacing_ReturnsPublicExposure()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            IsInternetFacing = true
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Exposure);
        Assert.Equal("public", result.Exposure.Level);
        Assert.True(result.Exposure.InternetFacing);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithIngressClass_ReturnsInternetFacing()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["kubernetes.io/ingress.class"] = "nginx"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Exposure);
        Assert.True(result.Exposure.InternetFacing);
        Assert.True(result.Exposure.BehindProxy);
    }

    [Trait("Category", TestCategories.Unit)]
        [Theory]
    [InlineData("LoadBalancer", "public", true)]
    [InlineData("NodePort", "internal", false)]
    [InlineData("ClusterIP", "private", false)]
    public void Extract_WithServiceType_ReturnsExpectedExposure(
        string serviceType, string expectedLevel, bool expectedInternetFacing)
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["service.type"] = serviceType
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Exposure);
        Assert.Equal(expectedLevel, result.Exposure.Level);
        Assert.Equal(expectedInternetFacing, result.Exposure.InternetFacing);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithExternalPorts_ReturnsInternalLevel()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            PortBindings = new Dictionary<int, string> { [443] = "https" }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Exposure);
        Assert.Equal("internal", result.Exposure.Level);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithDmzZone_ReturnsInternalLevel()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            NetworkZone = "dmz"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Exposure);
        Assert.Equal("internal", result.Exposure.Level);
        Assert.Equal("dmz", result.Exposure.Zone);
    }

    #endregion

    #region Extract - Surface Detection

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithServicePath_ReturnsSurfaceWithPath()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["service.path"] = "/api/v1"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("/api/v1", result.Surface.Path);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithRewriteTarget_ReturnsSurfaceWithPath()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/rewrite-target"] = "/backend"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("/backend", result.Surface.Path);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithNamespace_ReturnsSurfaceWithNamespacePath()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Namespace = "production"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("/production", result.Surface.Path);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithTlsAnnotation_ReturnsHttpsProtocol()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["cert-manager.io/cluster-issuer"] = "letsencrypt"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("https", result.Surface.Protocol);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithGrpcAnnotation_ReturnsGrpcProtocol()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["grpc.service"] = "UserService"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("grpc", result.Surface.Protocol);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithPortBinding_ReturnsSurfaceWithPort()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            PortBindings = new Dictionary<int, string> { [8080] = "http" }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal(8080, result.Surface.Port);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithIngressHost_ReturnsSurfaceWithHost()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["ingress.host"] = "api.example.com"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Surface);
        Assert.Equal("api.example.com", result.Surface.Host);
    }

    #endregion

    #region Extract - Auth Detection

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithBasicAuth_ReturnsBasicAuthType()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/auth-secret"] = "basic-auth-secret"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Auth);
        Assert.True(result.Auth.Required);
        Assert.Equal("basic", result.Auth.Type);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithOAuth_ReturnsOAuth2Type()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/oauth2-signin"] = "https://auth.example.com"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Auth);
        Assert.True(result.Auth.Required);
        Assert.Equal("oauth2", result.Auth.Type);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithMtls_ReturnsMtlsType()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/auth-tls-secret"] = "client-certs"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Auth);
        Assert.True(result.Auth.Required);
        Assert.Equal("mtls", result.Auth.Type);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithExplicitAuthType_ReturnsSpecifiedType()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/auth-type"] = "jwt"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Auth);
        Assert.True(result.Auth.Required);
        Assert.Equal("jwt", result.Auth.Type);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithAuthRoles_ReturnsRolesList()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/auth-type"] = "oauth2",
                ["nginx.ingress.kubernetes.io/auth-roles"] = "admin,editor,viewer"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Auth);
        Assert.NotNull(result.Auth.Roles);
        Assert.Equal(3, result.Auth.Roles.Count);
        Assert.Contains("admin", result.Auth.Roles);
        Assert.Contains("editor", result.Auth.Roles);
        Assert.Contains("viewer", result.Auth.Roles);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithNoAuth_ReturnsNullAuth()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Null(result.Auth);
    }

    #endregion

    #region Extract - Controls Detection

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithNetworkPolicy_ReturnsNetworkPolicyControl()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Namespace = "production",
            Annotations = new Dictionary<string, string>
            {
                ["network.policy.enabled"] = "true"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Controls);
        var control = Assert.Single(result.Controls);
        Assert.Equal("network_policy", control.Type);
        Assert.True(control.Active);
        Assert.Equal("production", control.Config);
        Assert.Equal("high", control.Effectiveness);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithRateLimit_ReturnsRateLimitControl()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/rate-limit"] = "100"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Controls);
        var control = Assert.Single(result.Controls);
        Assert.Equal("rate_limit", control.Type);
        Assert.True(control.Active);
        Assert.Equal("medium", control.Effectiveness);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithIpAllowlist_ReturnsIpAllowlistControl()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/whitelist-source-range"] = "10.0.0.0/8"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Controls);
        var control = Assert.Single(result.Controls);
        Assert.Equal("ip_allowlist", control.Type);
        Assert.True(control.Active);
        Assert.Equal("high", control.Effectiveness);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithWaf_ReturnsWafControl()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/enable-modsecurity"] = "true"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Controls);
        var control = Assert.Single(result.Controls);
        Assert.Equal("waf", control.Type);
        Assert.True(control.Active);
        Assert.Equal("high", control.Effectiveness);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithMultipleControls_ReturnsAllControls()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["network.policy.enabled"] = "true",
                ["nginx.ingress.kubernetes.io/rate-limit"] = "100",
                ["nginx.ingress.kubernetes.io/enable-modsecurity"] = "true"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.NotNull(result.Controls);
        Assert.Equal(3, result.Controls.Count);
        Assert.Contains(result.Controls, c => c.Type == "network_policy");
        Assert.Contains(result.Controls, c => c.Type == "rate_limit");
        Assert.Contains(result.Controls, c => c.Type == "waf");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithNoControls_ReturnsNullControls()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Null(result.Controls);
    }

    #endregion

    #region Extract - Confidence and Metadata

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_BaseConfidence_Returns0Point7()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal(0.7, result.Confidence, precision: 2);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithIngressAnnotation_IncreasesConfidence()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["nginx.ingress.kubernetes.io/rewrite-target"] = "/"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal(0.85, result.Confidence, precision: 2);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithServiceType_IncreasesConfidence()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["service.type"] = "ClusterIP"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal(0.8, result.Confidence, precision: 2);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_MaxConfidence_CapsAt0Point95()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Annotations = new Dictionary<string, string>
            {
                ["kubernetes.io/ingress.class"] = "nginx",
                ["service.type"] = "LoadBalancer"
            }
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.True(result.Confidence <= 0.95);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_ReturnsK8sSource()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal("k8s", result.Source);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_BuildsEvidenceRef_WithNamespaceAndEnvironment()
    {
        var root = new RichGraphRoot("root-123", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Namespace = "production",
            EnvironmentId = "env-456"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal("k8s/production/env-456/root-123", result.EvidenceRef);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_ReturnsNetworkKind()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s"
        };

        var result = _extractor.Extract(root, null, context);

        Assert.NotNull(result);
        Assert.Equal("network", result.Kind);
    }

    #endregion

    #region ExtractAsync

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task ExtractAsync_ReturnsSameResultAsExtract()
    {
        var root = new RichGraphRoot("root-1", "k8s", null);
        var context = BoundaryExtractionContext.Empty with
        {
            Source = "k8s",
            Namespace = "production",
            Annotations = new Dictionary<string, string>
            {
                ["kubernetes.io/ingress.class"] = "nginx"
            }
        };

        var syncResult = _extractor.Extract(root, null, context);
        var asyncResult = await _extractor.ExtractAsync(root, null, context);

        Assert.NotNull(syncResult);
        Assert.NotNull(asyncResult);
        Assert.Equal(syncResult.Kind, asyncResult.Kind);
        Assert.Equal(syncResult.Source, asyncResult.Source);
        Assert.Equal(syncResult.Confidence, asyncResult.Confidence);
    }

    #endregion

    #region Edge Cases

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WithNullRoot_ThrowsArgumentNullException()
    {
        var context = BoundaryExtractionContext.Empty with { Source = "k8s" };
        Assert.Throws<ArgumentNullException>(() => _extractor.Extract(null!, null, context));
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void Extract_WhenCannotHandle_ReturnsNull()
    {
        var root = new RichGraphRoot("root-1", "static", null);
        var context = BoundaryExtractionContext.Empty with { Source = "static" };

        var result = _extractor.Extract(root, null, context);

        Assert.Null(result);
    }

    #endregion
}