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using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using Moq;
using NUnit.Framework;
using Opc.Ua.Server.FileSystem;
using Opc.Ua.Server.Tests.NodeManager;
using Opc.Ua.Tests;

namespace Opc.Ua.Server.Tests.FileSystem
{
    /// <summary>
    /// Verifies Part 20 scoping, locking, mode validation and user access rules of the mounted file system.
    /// </summary>
    [TestFixture]
    [Category("FileSystem")]
    public sealed class FileSystemAccessRegressionTests
    {
        [SetUp]
        public void SetUp()
        {
            m_root = Path.Combine(Path.GetTempPath(), "fs-access-" + Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(Path.Combine(m_root, "a", "b"));
            Directory.CreateDirectory(Path.Combine(m_root, "c"));
            File.WriteAllText(Path.Combine(m_root, "a", "x.txt"), "x");
            File.WriteAllText(Path.Combine(m_root, "a", "b", "y.txt"), "y");
            File.WriteAllText(Path.Combine(m_root, "c", "secret.txt"), "secret");
            m_server = DeterministicServerMock.Create(out m_queues);
            m_server.SetupGet(s => s.Telemetry).Returns(NUnitTelemetryContext.Create());
            m_manager = new FileSystemNodeManager(
                m_server.Object,
                new ApplicationConfiguration(),
                new PhysicalFileSystemProvider(m_root, "AccessRegression"));
            m_manager.SystemContext.SessionId = new NodeId(100, 1);
        }

        [TearDown]
        public void TearDown()
        {
            m_manager.Dispose();
            m_queues.Dispose();
            if (Directory.Exists(m_root))
            {
                Directory.Delete(m_root, recursive: true);
            }
        }

        /// <summary>
        /// S12-1: a directory can only delete objects it organizes; other objects report Bad_NotFound.
        /// </summary>
        [Test]
        public async Task DeleteRejectsObjectsNotOrganizedByTheDirectoryAsync()
        {
            DirectoryObjectState a = CreateDirectory("a");

            ServiceResult sibling = await DeleteAsync(a, FileId("c/secret.txt")).ConfigureAwait(false);
            ServiceResult nested = await DeleteAsync(CreateRoot(), FileId("a/x.txt")).ConfigureAwait(false);
            ServiceResult unknown = await DeleteAsync(a, new NodeId("unknown", 0)).ConfigureAwait(false);
            ServiceResult child = await DeleteAsync(a, FileId("a/x.txt")).ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(sibling.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
                Assert.That(nested.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
                Assert.That(unknown.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
                Assert.That(ServiceResult.IsGood(child), Is.True, child.ToString());
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "c", "secret.txt")), Is.True);
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "a", "x.txt")), Is.False);
            });
        }

        /// <summary>
        /// S12-1: MoveOrCopy only accepts objects organized by the called directory.
        /// </summary>
        [Test]
        public async Task MoveOrCopyRejectsObjectsNotOrganizedByTheDirectoryAsync()
        {
            DirectoryObjectState a = CreateDirectory("a");

            MoveOrCopyMethodStateResult result = await a.MoveOrCopy!.OnCallAsync!(
                m_manager.SystemContext, a.MoveOrCopy, a.NodeId, FileId("c/secret.txt"), a.NodeId,
                false, "stolen.txt", CancellationToken.None).ConfigureAwait(false);

            Assert.That(result.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
            Assert.That(System.IO.File.Exists(Path.Combine(m_root, "c", "secret.txt")), Is.True);
        }

        /// <summary>
        /// S12-2: an open file, or a directory containing one, is locked and cannot be deleted or moved.
        /// </summary>
        [Test]
        public async Task DeleteAndMoveRejectOpenFilesAsync()
        {
            var file = new FileObjectState(m_manager.SystemContext, FileId("a/b/y.txt"), "a/b/y.txt", "y.txt");
            uint handle = await FileReadRegressionTests.OpenAsync(file, m_manager.SystemContext)
                .ConfigureAwait(false);

            ServiceResult deleteFile = await DeleteAsync(CreateDirectory("a/b"), FileId("a/b/y.txt"))
                .ConfigureAwait(false);
            ServiceResult deleteDirectory = await DeleteAsync(CreateDirectory("a"), DirId("a/b"))
                .ConfigureAwait(false);
            DirectoryObjectState root = CreateRoot();
            MoveOrCopyMethodStateResult move = await root.MoveOrCopy!.OnCallAsync!(
                m_manager.SystemContext, root.MoveOrCopy, root.NodeId, DirId("a"), DirId("c"),
                false, string.Empty, CancellationToken.None).ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(deleteFile.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(deleteDirectory.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(move.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "a", "b", "y.txt")), Is.True);
            });

            (ServiceResult closed, _) = await FileReadRegressionTests.CallAsync(
                file.Close!, m_manager.SystemContext, file.NodeId, [handle]).ConfigureAwait(false);
            Assert.That(ServiceResult.IsGood(closed), Is.True);
            ServiceResult deleted = await DeleteAsync(CreateDirectory("a"), DirId("a/b")).ConfigureAwait(false);
            Assert.That(ServiceResult.IsGood(deleted), Is.True, deleted.ToString());
        }

        /// <summary>
        /// S12-3: reserved mode bits and EraseExisting without Write are invalid; a reader
        /// cannot open a file that is open for writing.
        /// </summary>
        [Test]
        public async Task OpenValidatesModeAndReportsNotReadableAsync()
        {
            var file = new FileObjectState(m_manager.SystemContext, FileId("a/x.txt"), "a/x.txt", "x.txt");

            (ServiceResult eraseWithoutWrite, _) = await FileReadRegressionTests.CallAsync(
                file.Open!, m_manager.SystemContext, file.NodeId, [(byte)0x05]).ConfigureAwait(false);
            (ServiceResult reservedBits, _) = await FileReadRegressionTests.CallAsync(
                file.Open!, m_manager.SystemContext, file.NodeId, [(byte)0x11]).ConfigureAwait(false);
            await FileReadRegressionTests.OpenAsync(file, m_manager.SystemContext, 0x02).ConfigureAwait(false);
            (ServiceResult readWhileWriting, _) = await FileReadRegressionTests.CallAsync(
                file.Open!, m_manager.SystemContext, file.NodeId, [(byte)0x01]).ConfigureAwait(false);
            (ServiceResult writeWhileWriting, _) = await FileReadRegressionTests.CallAsync(
                file.Open!, m_manager.SystemContext, file.NodeId, [(byte)0x02]).ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(eraseWithoutWrite.StatusCode, Is.EqualTo(StatusCodes.BadInvalidArgument));
                Assert.That(reservedBits.StatusCode, Is.EqualTo(StatusCodes.BadInvalidArgument));
                Assert.That(readWhileWriting.StatusCode, Is.EqualTo(StatusCodes.BadNotReadable));
                Assert.That(writeWhileWriting.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
            });
        }

        /// <summary>
        /// S12-4: an anonymous user cannot modify the mount, and UserWritable / UserExecutable reflect it.
        /// </summary>
        [Test]
        public async Task AnonymousUserCannotModifyTheMountAsync()
        {
            m_manager.SystemContext.UserIdentity = new UserIdentity();
            DirectoryObjectState a = CreateDirectory("a");
            var file = new FileObjectState(m_manager.SystemContext, FileId("a/x.txt"), "a/x.txt", "x.txt");

            CreateFileMethodStateResult create = await a.CreateFile!.OnCallAsync!(
                m_manager.SystemContext, a.CreateFile, a.NodeId, "new.txt", false, CancellationToken.None)
                .ConfigureAwait(false);
            ServiceResult delete = await DeleteAsync(a, FileId("a/x.txt")).ConfigureAwait(false);
            (ServiceResult openWrite, _) = await FileReadRegressionTests.CallAsync(
                file.Open!, m_manager.SystemContext, file.NodeId, [(byte)0x02]).ConfigureAwait(false);
            uint readHandle = await FileReadRegressionTests.OpenAsync(file, m_manager.SystemContext)
                .ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(create.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadUserAccessDenied));
                Assert.That(delete.StatusCode, Is.EqualTo(StatusCodes.BadUserAccessDenied));
                Assert.That(openWrite.StatusCode, Is.EqualTo(StatusCodes.BadUserAccessDenied));
                Assert.That(readHandle, Is.Not.Zero);
                Assert.That(ReadBoolean(file.Writable!), Is.True);
                Assert.That(ReadBoolean(file.UserWritable!), Is.False);
                Assert.That(ReadUserExecutable(a.DeleteFileSystemObject!), Is.False);
                Assert.That(ReadUserExecutable(file.Write!), Is.False);
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "a", "x.txt")), Is.True);
            });
        }

        /// <summary>
        /// S12-4: authenticated users, and anonymous users when explicitly allowed, can modify the mount.
        /// </summary>
        [TestCase(false)]
        [TestCase(true)]
        public async Task AuthenticatedOrExplicitlyAllowedUserCanModifyTheMountAsync(bool anonymousAllowed)
        {
            m_manager.AllowAnonymousWrite = anonymousAllowed;
            m_manager.SystemContext.UserIdentity = anonymousAllowed
                ? new UserIdentity()
                : new UserIdentity("operator", "secret"u8);
            DirectoryObjectState a = CreateDirectory("a");
            var file = new FileObjectState(m_manager.SystemContext, FileId("a/x.txt"), "a/x.txt", "x.txt");

            Assert.That(ReadBoolean(file.UserWritable!), Is.True);
            Assert.That(ReadUserExecutable(a.DeleteFileSystemObject!), Is.True);
            ServiceResult delete = await DeleteAsync(a, FileId("a/x.txt")).ConfigureAwait(false);
            Assert.That(ServiceResult.IsGood(delete), Is.True, delete.ToString());
        }

        /// <summary>
        /// S12-5: copying or moving a directory into its own subtree is rejected.
        /// </summary>
        [TestCase(true)]
        [TestCase(false)]
        public async Task MoveOrCopyIntoOwnSubtreeIsRejectedAsync(bool createCopy)
        {
            DirectoryObjectState root = CreateRoot();

            MoveOrCopyMethodStateResult result = await root.MoveOrCopy!.OnCallAsync!(
                m_manager.SystemContext, root.MoveOrCopy, root.NodeId, DirId("a"), DirId("a/b"),
                createCopy, string.Empty, CancellationToken.None).ConfigureAwait(false);

            Assert.That(result.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadInvalidArgument));
            Assert.That(System.IO.Directory.Exists(Path.Combine(m_root, "a", "b", "a")), Is.False);
        }

        /// <summary>
        /// Review A3-6: a file-typed NodeId naming a directory cannot bypass the
        /// "into its own subtree" guard, and does not resolve to a node.
        /// </summary>
        [TestCase(true)]
        [TestCase(false)]
        public async Task MoveOrCopyDirectoryWithFileNodeIdIsRejectedAsync(bool createCopy)
        {
            DirectoryObjectState root = CreateRoot();

            MoveOrCopyMethodStateResult result = await root.MoveOrCopy!.OnCallAsync!(
                m_manager.SystemContext, root.MoveOrCopy, root.NodeId, FileId("a"), DirId("a/b"),
                createCopy, string.Empty, CancellationToken.None).ConfigureAwait(false);

            // Part 20 4.3.6: a NodeId of the wrong kind names no organized object.
            Assert.That(result.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
            Assert.That(System.IO.Directory.Exists(Path.Combine(m_root, "a", "b", "a")), Is.False);
            Assert.That(System.IO.Directory.Exists(Path.Combine(m_root, "a")), Is.True);
        }

        /// <summary>
        /// Spec gap Delete kind: a file-typed NodeId naming a directory (or a directory-typed
        /// NodeId naming a file) is not an object organized by the directory (Part 20 4.3.5),
        /// so Delete returns Bad_NotFound and removes nothing.
        /// </summary>
        [Test]
        public async Task DeleteWithMismatchedNodeIdKindReturnsNotFoundAsync()
        {
            DirectoryObjectState root = CreateRoot();
            DirectoryObjectState a = CreateDirectory("a");

            ServiceResult directoryAsFile = await DeleteAsync(root, FileId("a")).ConfigureAwait(false);
            ServiceResult fileAsDirectory = await DeleteAsync(a, DirId("a/x.txt")).ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(directoryAsFile.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
                Assert.That(fileAsDirectory.StatusCode, Is.EqualTo(StatusCodes.BadNotFound));
                Assert.That(System.IO.Directory.Exists(Path.Combine(m_root, "a", "b")), Is.True);
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "a", "x.txt")), Is.True);
            });
        }

        /// <summary>
        /// Review D-7: an open still waiting for its provider stream locks the file, so a
        /// Delete or Move issued in that window is rejected instead of racing the open.
        /// </summary>
        [Test]
        public async Task PendingOpenLocksFileAgainstDeleteAndMoveAsync()
        {
            var openEntered = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
            var releaseOpen = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
            using FileSystemNodeManager manager = CreateGatedManager(provider => provider
                .Setup(p => p.OpenReadAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>(async (path, ct) =>
                {
                    openEntered.TrySetResult(true);
                    await releaseOpen.Task.ConfigureAwait(false);
                    return await m_physical.OpenReadAsync(path, ct).ConfigureAwait(false);
                }));
            var file = new FileObjectState(manager.SystemContext, FileId(manager, "a/b/y.txt"), "a/b/y.txt", "y.txt");

            Task<(ServiceResult Result, System.Collections.Generic.List<Variant> Output)> open =
                FileReadRegressionTests.CallAsync(file.Open!, manager.SystemContext, file.NodeId, [(byte)0x01])
                    .AsTask();
            await openEntered.Task.WaitAsync(TimeSpan.FromSeconds(10)).ConfigureAwait(false);

            ServiceResult deleteFile = await DeleteAsync(manager, CreateDirectory(manager, "a/b"), FileId(manager, "a/b/y.txt"))
                .ConfigureAwait(false);
            ServiceResult deleteDirectory = await DeleteAsync(manager, CreateDirectory(manager, "a"), DirId(manager, "a/b"))
                .ConfigureAwait(false);
            DirectoryObjectState root = CreateRoot(manager);
            MoveOrCopyMethodStateResult move = await root.MoveOrCopy!.OnCallAsync!(
                manager.SystemContext, root.MoveOrCopy, root.NodeId, DirId(manager, "a"), DirId(manager, "c"),
                false, string.Empty, CancellationToken.None).ConfigureAwait(false);

            releaseOpen.TrySetResult(true);
            (ServiceResult opened, _) = await open.WaitAsync(TimeSpan.FromSeconds(10)).ConfigureAwait(false);

            Assert.Multiple(() =>
            {
                Assert.That(deleteFile.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(deleteDirectory.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(move.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(ServiceResult.IsGood(opened), Is.True, opened.ToString());
                Assert.That(System.IO.File.Exists(Path.Combine(m_root, "a", "b", "y.txt")), Is.True);
            });
        }

        /// <summary>
        /// Review D-7: while a Delete runs, a new open of a file below the deleted path is
        /// refused instead of opening a stream on an entry that is being removed.
        /// </summary>
        [Test]
        public async Task OpenIsRefusedWhileDeleteOfAncestorRunsAsync()
        {
            var deleteEntered = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
            var releaseDelete = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
            using FileSystemNodeManager manager = CreateGatedManager(provider => provider
                .Setup(p => p.DeleteAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>(async (path, ct) =>
                {
                    deleteEntered.TrySetResult(true);
                    await releaseDelete.Task.ConfigureAwait(false);
                    await m_physical.DeleteAsync(path, ct).ConfigureAwait(false);
                }));
            var file = new FileObjectState(manager.SystemContext, FileId(manager, "a/b/y.txt"), "a/b/y.txt", "y.txt");

            ServiceResult openDuringDelete;
            ServiceResult writeOpenDuringDelete;
            ServiceResult deleted;
#pragma warning disable CA2025 // awaited in the finally below, before the manager is disposed
            Task<ServiceResult> delete = DeleteAsync(manager, CreateDirectory(manager, "a"), DirId(manager, "a/b"));
#pragma warning restore CA2025
            try
            {
                await deleteEntered.Task.WaitAsync(TimeSpan.FromSeconds(10)).ConfigureAwait(false);

                (openDuringDelete, _) = await FileReadRegressionTests.CallAsync(
                    file.Open!, manager.SystemContext, file.NodeId, [(byte)0x01]).ConfigureAwait(false);
                (writeOpenDuringDelete, _) = await FileReadRegressionTests.CallAsync(
                    file.Open!, manager.SystemContext, file.NodeId, [(byte)0x02]).ConfigureAwait(false);
            }
            finally
            {
                // the delete must finish before the manager is disposed.
                releaseDelete.TrySetResult(true);
                deleted = await delete.WaitAsync(TimeSpan.FromSeconds(10)).ConfigureAwait(false);
            }

            Assert.Multiple(() =>
            {
                // Part 20 4.2.2: a locked file is not readable / not writable.
                Assert.That(openDuringDelete.StatusCode, Is.EqualTo(StatusCodes.BadNotReadable));
                Assert.That(writeOpenDuringDelete.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(ServiceResult.IsGood(deleted), Is.True, deleted.ToString());
                Assert.That(System.IO.Directory.Exists(Path.Combine(m_root, "a", "b")), Is.False);
            });

            // The block ends with the mutation: other files open again.
            var other = new FileObjectState(manager.SystemContext, FileId(manager, "a/x.txt"), "a/x.txt", "x.txt");
            uint handle = await FileReadRegressionTests.OpenAsync(other, manager.SystemContext).ConfigureAwait(false);
            Assert.That(handle, Is.Not.Zero);
        }

        /// <summary>
        /// Creates a node manager over a provider that forwards to the physical mount
        /// except for the members <paramref name="configure"/> overrides.
        /// </summary>
        private FileSystemNodeManager CreateGatedManager(Action<Mock<IFileSystemProvider>> configure)
        {
            m_physical = new PhysicalFileSystemProvider(m_root, "Gated");
            var provider = new Mock<IFileSystemProvider>(MockBehavior.Strict);
            provider.SetupGet(p => p.MountName).Returns("Gated");
            provider.SetupGet(p => p.IsWritable).Returns(true);
            provider.Setup(p => p.GetEntryAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>((path, ct) => m_physical.GetEntryAsync(path, ct));
            provider.Setup(p => p.EnumerateAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>((path, ct) => m_physical.EnumerateAsync(path, ct));
            provider.Setup(p => p.OpenReadAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>((path, ct) => m_physical.OpenReadAsync(path, ct));
            provider.Setup(p => p.OpenWriteAsync(
                    It.IsAny<string>(), It.IsAny<FileWriteMode>(), It.IsAny<CancellationToken>()))
                .Returns<string, FileWriteMode, CancellationToken>(
                    (path, mode, ct) => m_physical.OpenWriteAsync(path, mode, ct));
            provider.Setup(p => p.DeleteAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, CancellationToken>((path, ct) => m_physical.DeleteAsync(path, ct));
            provider.Setup(p => p.MoveAsync(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
                .Returns<string, string, CancellationToken>(
                    (source, target, ct) => m_physical.MoveAsync(source, target, ct));
            configure(provider);
            var manager = new FileSystemNodeManager(m_server.Object, new ApplicationConfiguration(), provider.Object);
            manager.SystemContext.SessionId = new NodeId(101, 1);
            return manager;
        }

        private NodeId FileId(string providerPath)
        {
            return FileSystemNodeId.BuildFile(providerPath, m_manager.NamespaceIndex);
        }

        private NodeId DirId(string providerPath)
        {
            return FileSystemNodeId.BuildDirectory(providerPath, m_manager.NamespaceIndex);
        }

        private static NodeId FileId(FileSystemNodeManager manager, string providerPath)
        {
            return FileSystemNodeId.BuildFile(providerPath, manager.NamespaceIndex);
        }

        private static NodeId DirId(FileSystemNodeManager manager, string providerPath)
        {
            return FileSystemNodeId.BuildDirectory(providerPath, manager.NamespaceIndex);
        }

        private DirectoryObjectState CreateRoot()
        {
            return CreateRoot(m_manager);
        }

        private static DirectoryObjectState CreateRoot(FileSystemNodeManager manager)
        {
            return new DirectoryObjectState(manager.SystemContext,
                FileSystemNodeId.BuildRoot(manager.NamespaceIndex), string.Empty, "Root", isRoot: true);
        }

        private DirectoryObjectState CreateDirectory(string providerPath)
        {
            return CreateDirectory(m_manager, providerPath);
        }

        private static DirectoryObjectState CreateDirectory(FileSystemNodeManager manager, string providerPath)
        {
            return new DirectoryObjectState(manager.SystemContext,
                FileSystemNodeId.BuildDirectory(providerPath, manager.NamespaceIndex), providerPath,
                Path.GetFileName(providerPath), isRoot: false);
        }

        private Task<ServiceResult> DeleteAsync(DirectoryObjectState directory, NodeId objectToDelete)
        {
            return DeleteAsync(m_manager, directory, objectToDelete);
        }

        private static async Task<ServiceResult> DeleteAsync(
            FileSystemNodeManager manager, DirectoryObjectState directory, NodeId objectToDelete)
        {
            DeleteFileMethodStateResult result = await directory.DeleteFileSystemObject!.OnCallAsync!(
                manager.SystemContext, directory.DeleteFileSystemObject, directory.NodeId, objectToDelete,
                CancellationToken.None).ConfigureAwait(false);
            return result.ServiceResult;
        }

        private bool ReadBoolean(NodeState node)
        {
            return ReadBooleanAttribute(node, Attributes.Value);
        }

        private bool ReadUserExecutable(NodeState method)
        {
            return ReadBooleanAttribute(method, Attributes.UserExecutable);
        }

        private bool ReadBooleanAttribute(NodeState node, uint attributeId)
        {
            (ServiceResult result, DataValue value) = node.ReadAttributeAsync(
                m_manager.SystemContext, attributeId, NumericRange.Null, QualifiedName.Null, default)
                .AsTask().GetAwaiter().GetResult();
            Assert.That(ServiceResult.IsGood(result), Is.True, result.ToString());
            Assert.That(value.WrappedValue.TryGetValue(out bool flag), Is.True);
            return flag;
        }

        private string m_root;
        private PhysicalFileSystemProvider m_physical = null!;
        private Mock<IServerInternal> m_server;
        private MonitoredItemQueueFactory m_queues = null!;
        private FileSystemNodeManager m_manager;
    }
}