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 *
 * OPC Foundation MIT License 1.00
 *
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 * obtaining a copy of this software and associated documentation
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using System;
using System.Reflection;
using NUnit.Framework;
using Opc.Ua.Tests;

namespace Opc.Ua.Core.Tests.Stack.Client
{
    /// <summary>
    /// Tests for ConfiguredEndpoint matching.
    /// </summary>
    [TestFixture]
    [Category("Client")]
    [SetCulture("en-us")]
    [SetUICulture("en-us")]
    [Parallelizable]
    public class ConfiguredEndpointTests
    {
        /// <summary>
        /// Test that when a requested security policy is not supported by the server,
        /// BadSecurityPolicyRejected is thrown instead of BadUserAccessDenied.
        /// </summary>
        [Test]
        public void MatchEndpoints_ThrowsBadSecurityPolicyRejected_WhenPolicyNotSupported()
        {
            ITelemetryContext telemetry = NUnitTelemetryContext.Create();

            // Create server endpoints with only None and Basic256Sha256
            ArrayOf<EndpointDescription> serverEndpoints =
            [
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.None,
                    SecurityPolicyUri = SecurityPolicies.None
                },
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.SignAndEncrypt,
                    SecurityPolicyUri = SecurityPolicies.Basic256Sha256
                }
            ];

            // Try to match with a security policy that doesn't exist (Aes256_Sha256_RsaPss)
            TargetInvocationException ex = Assert.Throws<TargetInvocationException>(
                () => InvokeMatchEndpoints(
                    serverEndpoints,
                    new Uri("opc.tcp://localhost:4840"),
                    MessageSecurityMode.SignAndEncrypt,
                    SecurityPolicies.Aes256_Sha256_RsaPss
                ));

            Assert.IsInstanceOf<ServiceResultException>(ex.InnerException);
            var serviceException = (ServiceResultException)ex.InnerException!;
            Assert.That(serviceException!.StatusCode, Is.EqualTo(StatusCodes.BadSecurityPolicyRejected));
            Assert.That(serviceException.Message, Does.Contain(SecurityPolicies.Aes256_Sha256_RsaPss));
        }

        /// <summary>
        /// Test that when a requested security mode is not supported by the server,
        /// BadSecurityModeRejected is thrown.
        /// </summary>
        [Test]
        public void MatchEndpoints_ThrowsBadSecurityModeRejected_WhenModeNotSupported()
        {
            ITelemetryContext telemetry = NUnitTelemetryContext.Create();

            // Create server endpoints with only None security mode
            ArrayOf<EndpointDescription> serverEndpoints =
            [
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.None,
                    SecurityPolicyUri = SecurityPolicies.None
                }
            ];

            // Try to match with SignAndEncrypt mode that doesn't exist
            TargetInvocationException ex = Assert.Throws<TargetInvocationException>(() => InvokeMatchEndpoints(
                    serverEndpoints,
                    new Uri("opc.tcp://localhost:4840"),
                    MessageSecurityMode.SignAndEncrypt,
                    null! // no specific policy requested, only mode
                ));

            Assert.IsInstanceOf<ServiceResultException>(ex.InnerException);
            var serviceException = (ServiceResultException)ex.InnerException!;
            Assert.That(serviceException!.StatusCode, Is.EqualTo(StatusCodes.BadSecurityModeRejected));
            Assert.That(serviceException.Message, Does.Contain("SignAndEncrypt"));
        }

        /// <summary>
        /// Test that when both security policy and mode are not supported,
        /// BadSecurityPolicyRejected is thrown with information about both.
        /// </summary>
        [Test]
        public void MatchEndpoints_ThrowsBadSecurityPolicyRejected_WhenBothPolicyAndModeNotSupported()
        {
            ITelemetryContext telemetry = NUnitTelemetryContext.Create();

            // Create server endpoints with only None
            ArrayOf<EndpointDescription> serverEndpoints =
            [
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.None,
                    SecurityPolicyUri = SecurityPolicies.None
                }
            ];

            // Try to match with both policy and mode that don't exist
            TargetInvocationException ex = Assert.Throws<TargetInvocationException>(() => InvokeMatchEndpoints(
                    serverEndpoints,
                    new Uri("opc.tcp://localhost:4840"),
                    MessageSecurityMode.SignAndEncrypt,
                    SecurityPolicies.Basic256Sha256
                ));

            Assert.IsInstanceOf<ServiceResultException>(ex.InnerException);
            var serviceException = (ServiceResultException)ex.InnerException!;
            Assert.That(serviceException!.StatusCode, Is.EqualTo(StatusCodes.BadSecurityPolicyRejected));
            Assert.That(serviceException.Message, Does.Contain(SecurityPolicies.Basic256Sha256));
            Assert.That(serviceException.Message, Does.Contain("SignAndEncrypt"));
        }

        /// <summary>
        /// Test that when no specific security parameters are requested,
        /// the method returns available endpoints without throwing.
        /// </summary>
        [Test]
        public void MatchEndpoints_ReturnsEndpoints_WhenNoSecurityParametersSpecified()
        {
            // Create server endpoints
            ArrayOf<EndpointDescription> serverEndpoints =
            [
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.None,
                    SecurityPolicyUri = SecurityPolicies.None
                },
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.SignAndEncrypt,
                    SecurityPolicyUri = SecurityPolicies.Basic256Sha256
                }
            ];

            // Match without specifying security parameters
            ArrayOf<EndpointDescription> matches = InvokeMatchEndpoints(
                serverEndpoints,
                new Uri("opc.tcp://localhost:4840"),
                MessageSecurityMode.Invalid,
                null!
            );

            // Should return available endpoints
            Assert.That(matches.IsNull, Is.False);
            Assert.That(matches.IsEmpty, Is.False);
        }

        /// <summary>
        /// Test that matching works correctly when the requested security parameters exist.
        /// </summary>
        [Test]
        public void MatchEndpoints_ReturnsMatchingEndpoint_WhenSecurityParametersMatch()
        {
            // Create server endpoints
            ArrayOf<EndpointDescription> serverEndpoints =
            [
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.None,
                    SecurityPolicyUri = SecurityPolicies.None
                },
                new EndpointDescription
                {
                    EndpointUrl = "opc.tcp://localhost:4840",
                    SecurityMode = MessageSecurityMode.SignAndEncrypt,
                    SecurityPolicyUri = SecurityPolicies.Basic256Sha256
                }
            ];

            // Match with existing security parameters
            ArrayOf<EndpointDescription> matches = InvokeMatchEndpoints(
                serverEndpoints,
                new Uri("opc.tcp://localhost:4840"),
                MessageSecurityMode.SignAndEncrypt,
                SecurityPolicies.Basic256Sha256
            );

            // Should return the matching endpoint
            Assert.That(matches.IsNull, Is.False);
            Assert.That(matches.Count, Is.EqualTo(1));
            Assert.That(matches[0].SecurityPolicyUri, Is.EqualTo(SecurityPolicies.Basic256Sha256));
            Assert.That(matches[0].SecurityMode, Is.EqualTo(MessageSecurityMode.SignAndEncrypt));
        }

        /// <summary>
        /// Helper method to invoke the private MatchEndpoints method via reflection.
        /// </summary>
        private static ArrayOf<EndpointDescription> InvokeMatchEndpoints(
            ArrayOf<EndpointDescription> collection,
            Uri endpointUrl,
            MessageSecurityMode securityMode,
            string securityPolicyUri,
            string? transportProfileUri = null)
        {
            Type configuredEndpointType = typeof(ConfiguredEndpoint);
            MethodInfo matchEndpointsMethod = configuredEndpointType.GetMethod(
                "MatchEndpoints",
                BindingFlags.NonPublic | BindingFlags.Static,
                null,
                [typeof(ArrayOf<EndpointDescription>), typeof(Uri), typeof(MessageSecurityMode), typeof(string), typeof(string)],
                null
            )!;

            Assert.That(matchEndpointsMethod, Is.Not.Null, "MatchEndpoints method not found");

            return (ArrayOf<EndpointDescription>)matchEndpointsMethod.Invoke(
                null,
                [collection, endpointUrl, securityMode, securityPolicyUri, transportProfileUri]
            )!;
        }

        [Test]
        public void DefaultConstructorCreatesValidInstance()
        {
            var endpoint = new ConfiguredEndpoint();
            Assert.That(endpoint.Description, Is.Not.Null);
            Assert.That(endpoint.BinaryEncodingSupport, Is.EqualTo(BinaryEncodingSupport.Optional));
            Assert.That(endpoint.UpdateBeforeConnect, Is.True);
        }

        [Test]
        public void ConstructorWithCollectionAndDescription()
        {
            var description = new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                SecurityMode = MessageSecurityMode.None,
                SecurityPolicyUri = SecurityPolicies.None
            };
            var endpoint = new ConfiguredEndpoint(null!, description);

            Assert.That(endpoint.Description, Is.Not.Null);
            Assert.That(endpoint.Description.EndpointUrl, Is.EqualTo("opc.tcp://localhost:4840"));
            Assert.That(endpoint.Configuration, Is.Not.Null);
            Assert.That(endpoint.Collection, Is.Null);
        }

        [Test]
        public void ConstructorWithCollectionDescriptionAndConfiguration()
        {
            var description = new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                SecurityMode = MessageSecurityMode.SignAndEncrypt,
                SecurityPolicyUri = SecurityPolicies.Basic256Sha256
            };
            var configuration = EndpointConfiguration.Create();
            var endpoint = new ConfiguredEndpoint(null, description, configuration);

            Assert.That(endpoint.Description.SecurityMode, Is.EqualTo(MessageSecurityMode.SignAndEncrypt));
            Assert.That(endpoint.Configuration, Is.Not.Null);
        }

        [Test]
        public void ConstructorWithNullDescriptionThrows()
        {
            Assert.Throws<ArgumentNullException>(() =>
                new ConfiguredEndpoint(null!, (EndpointDescription)null!));
        }

        [Test]
        public void ConstructorWithApplicationDescription()
        {
            var server = new ApplicationDescription
            {
                ApplicationName = new LocalizedText("TestServer"),
                ApplicationUri = "urn:test:server",
                ApplicationType = ApplicationType.Server,
                DiscoveryUrls = ["opc.tcp://localhost:4840/discovery"]
            };
            var config = EndpointConfiguration.Create();
            var endpoint = new ConfiguredEndpoint(server, config);

            Assert.That(endpoint.Description, Is.Not.Null);
            Assert.That(endpoint.Description.Server, Is.SameAs(server));
            Assert.That(endpoint.Description.EndpointUrl, Is.Not.Null.And.Not.Empty);
        }

        [Test]
        public void ConstructorWithNullApplicationDescriptionThrows()
        {
            Assert.Throws<ArgumentNullException>(() =>
                new ConfiguredEndpoint(null!, EndpointConfiguration.Create()));
        }

        [Test]
        public void ConstructorWithHttpsDiscoveryUrl()
        {
            var server = new ApplicationDescription
            {
                ApplicationName = new LocalizedText("TestServer"),
                ApplicationUri = "urn:test:server",
                ApplicationType = ApplicationType.Server,
                DiscoveryUrls = ["https://localhost:4840/discovery"]
            };
            var endpoint = new ConfiguredEndpoint(server, EndpointConfiguration.Create());

            Assert.That(endpoint.Description.EndpointUrl, Does.Not.EndWith("/discovery"));
        }

        [Test]
        public void UpdateWithEndpointDescription()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                SecurityMode = MessageSecurityMode.None,
                SecurityPolicyUri = SecurityPolicies.None
            });

            var newDescription = new EndpointDescription
            {
                EndpointUrl = "opc.tcp://remotehost:4841",
                SecurityMode = MessageSecurityMode.SignAndEncrypt,
                SecurityPolicyUri = SecurityPolicies.Basic256Sha256
            };
            endpoint.Update(newDescription);

            Assert.That(endpoint.Description.EndpointUrl, Is.EqualTo("opc.tcp://remotehost:4841"));
            Assert.That(endpoint.Description.SecurityMode, Is.EqualTo(MessageSecurityMode.SignAndEncrypt));
        }

        [Test]
        public void UpdateWithNullDescriptionThrows()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.Throws<ArgumentNullException>(() => endpoint.Update((EndpointDescription)null!));
        }

        [Test]
        public void UpdateWithEndpointConfiguration()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            var config = EndpointConfiguration.Create();
            endpoint.Update(config);

            Assert.That(endpoint.Configuration, Is.Not.Null);
        }

        [Test]
        public void UpdateWithNullConfigurationThrows()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.Throws<ArgumentNullException>(() => endpoint.Update((EndpointConfiguration)null!));
        }

        [Test]
        public void UpdateWithConfiguredEndpoint()
        {
            var source = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://remotehost:4841",
                SecurityMode = MessageSecurityMode.SignAndEncrypt,
                SecurityPolicyUri = SecurityPolicies.Basic256Sha256
            })
            {
                UpdateBeforeConnect = false
            };

            var target = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            target.Update(source);

            Assert.That(target.Description.EndpointUrl, Is.EqualTo("opc.tcp://remotehost:4841"));
            Assert.That(target.UpdateBeforeConnect, Is.False);
        }

        [Test]
        public void UpdateWithNullConfiguredEndpointThrows()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.Throws<ArgumentNullException>(() => endpoint.Update((ConfiguredEndpoint)null!));
        }

        [Test]
        public void ToStringReturnsFormattedString()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                SecurityMode = MessageSecurityMode.SignAndEncrypt,
                SecurityPolicyUri = SecurityPolicies.Basic256Sha256
            });

            string result = endpoint.ToString();
            Assert.That(result, Does.Contain("opc.tcp://localhost:4840"));
            Assert.That(result, Does.Contain("SignAndEncrypt"));
        }

        [Test]
        public void ToStringWithInvalidFormatThrows()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.Throws<FormatException>(() => endpoint.ToString("X", null));
        }

        [Test]
        public void EndpointUrlPropertyGetterReturnsUri()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Uri url = endpoint.EndpointUrl!;
            Assert.That(url, Is.Not.Null);
            Assert.That(url.Host, Is.EqualTo("localhost"));
            Assert.That(url.Port, Is.EqualTo(4840));
        }

        [Test]
        public void EndpointUrlPropertySetterUpdatesDescription()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            })
            {
                EndpointUrl = new Uri("opc.tcp://newhost:5000")
            };
            Assert.That(endpoint.Description.EndpointUrl, Does.Contain("newhost"));
        }

        [Test]
        public void EndpointUrlPropertySetterWithNull()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            })
            {
                EndpointUrl = null
            };
            Assert.That(endpoint.EndpointUrl, Is.Null);
        }

        [Test]
        public void EndpointUrlPropertyReturnsNullForEmptyUrl()
        {
            var endpoint = new ConfiguredEndpoint();
            Assert.That(endpoint.EndpointUrl, Is.Null);
        }

        [Test]
        public void SelectedUserTokenPolicyReturnsNullWhenNoTokens()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.That(endpoint.SelectedUserTokenPolicy, Is.Null);
        }

        [Test]
        public void SelectedUserTokenPolicyReturnsCorrectPolicy()
        {
            var policy = new UserTokenPolicy(UserTokenType.Anonymous);
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                UserIdentityTokens = [policy]
            })
            {
                SelectedUserTokenPolicyIndex = 0
            };

            Assert.That(endpoint.SelectedUserTokenPolicy, Is.Not.Null);
            Assert.That(endpoint.SelectedUserTokenPolicy.TokenType, Is.EqualTo(UserTokenType.Anonymous));
        }

        /// <summary>
        /// Verifies selecting an advertised user-token policy preserves its index and clears unmatched selections.
        /// </summary>
        [TestCase(0)]
        [TestCase(1)]
        public void SelectedUserTokenPolicySetterPreservesMatchingPolicy(int index)
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost",
                UserIdentityTokens =
                [
                    new UserTokenPolicy(UserTokenType.Anonymous),
                    new UserTokenPolicy(UserTokenType.UserName)
                ]
            });
            UserTokenPolicy selected = endpoint.Description.UserIdentityTokens[index];
            endpoint.SelectedUserTokenPolicy = selected;
            Assert.That(endpoint.SelectedUserTokenPolicyIndex, Is.EqualTo(index));
            Assert.That(endpoint.SelectedUserTokenPolicy, Is.SameAs(selected));

            endpoint.SelectedUserTokenPolicy = new UserTokenPolicy(UserTokenType.Certificate);
            Assert.That(endpoint.SelectedUserTokenPolicyIndex, Is.EqualTo(-1));
            Assert.That(endpoint.SelectedUserTokenPolicy, Is.Null);
            endpoint.SelectedUserTokenPolicy = null;
            Assert.That(endpoint.SelectedUserTokenPolicyIndex, Is.EqualTo(-1));
        }

        /// <summary>
        /// Assigning a policy selects it. The setter used to break out of its
        /// search loop and fall through to the not-found assignment, so the
        /// index always ended at -1 and the selection was silently discarded.
        /// </summary>
        [TestCase(0)]
        [TestCase(1)]
        [TestCase(2)]
        public void SelectedUserTokenPolicySetterSelectsTheAssignedPolicy(int index)
        {
            var anonymous = new UserTokenPolicy(UserTokenType.Anonymous);
            var userName = new UserTokenPolicy(UserTokenType.UserName);
            var certificate = new UserTokenPolicy(UserTokenType.Certificate);
            UserTokenPolicy[] policies = [anonymous, userName, certificate];

            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                UserIdentityTokens = [.. policies]
            })
            {
                SelectedUserTokenPolicy = policies[index]
            };

            Assert.That(endpoint.SelectedUserTokenPolicyIndex, Is.EqualTo(index));
            Assert.That(
                endpoint.SelectedUserTokenPolicy?.TokenType,
                Is.EqualTo(policies[index].TokenType));
        }

        /// <summary>
        /// A policy the endpoint does not offer clears the selection.
        /// </summary>
        [Test]
        public void SelectedUserTokenPolicySetterClearsForAnUnknownPolicy()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                UserIdentityTokens = [new UserTokenPolicy(UserTokenType.Anonymous)]
            })
            {
                SelectedUserTokenPolicy = new UserTokenPolicy(UserTokenType.UserName)
            };

            Assert.That(endpoint.SelectedUserTokenPolicyIndex, Is.EqualTo(-1));
            Assert.That(endpoint.SelectedUserTokenPolicy, Is.Null);
        }

        [Test]
        public void SelectedUserTokenPolicyIndexOutOfRangeReturnsNull()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                UserIdentityTokens = [
                    new UserTokenPolicy(UserTokenType.Anonymous)
                ]
            })
            {
                SelectedUserTokenPolicyIndex = 99
            };
            Assert.That(endpoint.SelectedUserTokenPolicy, Is.Null);
        }

        [Test]
        public void NeedUpdateFromServerReturnsFalseWithNoneSecurity()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                SecurityMode = MessageSecurityMode.None,
                SecurityPolicyUri = SecurityPolicies.None,
                UserIdentityTokens = [
                    new UserTokenPolicy(UserTokenType.Anonymous)
                ]
            })
            {
                SelectedUserTokenPolicyIndex = 0
            };

            Assert.That(endpoint.NeedUpdateFromServer(), Is.False);
        }

        [Test]
        public void UpdateFromServerWithNullApplicationConfigurationThrowsArgumentNullException()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.wss://localhost:4840",
                SecurityMode = MessageSecurityMode.None,
                SecurityPolicyUri = SecurityPolicies.None
            });

            ArgumentNullException ex = Assert.ThrowsAsync<ArgumentNullException>(async () =>
                await endpoint.UpdateFromServerAsync(
                    (ApplicationConfiguration)null!,
                    telemetry: null));
            Assert.That(ex.ParamName, Is.EqualTo("applicationConfiguration"));
        }

        [Test]
        public void GetDiscoveryUrlWithHttpScheme()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "https://localhost:4840"
            });
            Uri discoveryUrl = endpoint.GetDiscoveryUrl(new Uri("https://localhost:4840"));
            Assert.That(discoveryUrl, Is.Not.Null);
            Assert.That(discoveryUrl.ToString(), Does.Contain("discovery"));
        }

        [Test]
        public void GetDiscoveryUrlWithOpcTcpScheme()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Uri discoveryUrl = endpoint.GetDiscoveryUrl(new Uri("opc.tcp://localhost:4840"));
            Assert.That(discoveryUrl, Is.Not.Null);
        }

        [Test]
        public void GetDiscoveryUrlWithServerDiscoveryUrls()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840",
                Server = new ApplicationDescription
                {
                    DiscoveryUrls = [
                        "opc.tcp://localhost:4840/discovery"
                    ]
                }
            });
            Uri discoveryUrl = endpoint.GetDiscoveryUrl(new Uri("opc.tcp://localhost:4840"));
            Assert.That(discoveryUrl, Is.Not.Null);
        }

        [Test]
        public void GetDiscoveryUrlWithNullUsesEndpointUrl()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Uri discoveryUrl = endpoint.GetDiscoveryUrl(null!);
            Assert.That(discoveryUrl, Is.Not.Null);
        }

        [Test]
        public void BinaryEncodingSupportProperty()
        {
            var endpoint = new ConfiguredEndpoint
            {
                BinaryEncodingSupport = BinaryEncodingSupport.Required
            };
            Assert.That(endpoint.BinaryEncodingSupport, Is.EqualTo(BinaryEncodingSupport.Required));

            endpoint.BinaryEncodingSupport = BinaryEncodingSupport.None;
            Assert.That(endpoint.BinaryEncodingSupport, Is.EqualTo(BinaryEncodingSupport.None));
        }

        [Test]
        public void UserIdentityProperty()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.That(endpoint.UserIdentity, Is.Null);
            var token = new AnonymousIdentityToken();
            endpoint.UserIdentity = token;
            Assert.That(endpoint.UserIdentity, Is.SameAs(token));
        }

        [Test]
        public void ReverseConnectProperty()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.That(endpoint.ReverseConnect, Is.Null);
        }

        [Test]
        public void ExtensionsProperty()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.That(endpoint.Extensions.IsNull, Is.True);
        }

        [Test]
        public void UpdateBeforeConnectDefaultIsTrue()
        {
            var endpoint = new ConfiguredEndpoint(null!, new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            });
            Assert.That(endpoint.UpdateBeforeConnect, Is.True);
        }

        [Test]
        public void ConstructorWithCollectionUsesDefaultConfiguration()
        {
            var collection = new ConfiguredEndpointCollection();
            var description = new EndpointDescription
            {
                EndpointUrl = "opc.tcp://localhost:4840"
            };
            var endpoint = new ConfiguredEndpoint(collection, description);
            Assert.That(endpoint.Collection, Is.SameAs(collection));
            Assert.That(endpoint.Configuration, Is.Not.Null);
        }

        [Test]
        public void DiscoverySuffixConstant()
        {
            Assert.That(ConfiguredEndpoint.DiscoverySuffix, Is.EqualTo("/discovery"));
        }
    }
}