// Shows how to find all registrations in the GDS.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.Discovery;
using OpcLabs.EasyOpc.UA.Extensions;
using OpcLabs.EasyOpc.UA.Gds;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.Gds._EasyUAGlobalDiscoveryClient
{
    class FindApplications
    {
        public static void Main1()
        {
            // Define which GDS we will work with.
            UAEndpointDescriptor gdsEndpointDescriptor =
                ((UAEndpointDescriptor)"opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer")
                .WithUserNameIdentity("appuser", "demo");

            // Instantiate the global discovery client object
            var globalDiscoveryClient = new EasyUAGlobalDiscoveryClient();

            // Find all (client or server) applications registered in the GDS.
            UAApplicationDescription[] applicationDescriptionArray;
            try
            {
                globalDiscoveryClient.QueryApplications(
                    gdsEndpointDescriptor: gdsEndpointDescriptor,
                    startingRecordId: 0,
                    maximumRecordsToReturn: 0,
                    applicationName: "",
                    applicationUriString: "",
                    applicationTypes: UAApplicationTypes.All,
                    productUriString: "",
                    serverCapabilities: new string[0],
                    lastCounterResetTime: out _,
                    nextRecordId: out _,
                    applications: out applicationDescriptionArray);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // For each application returned by the query, find its registrations in the GDS.
            foreach (UAApplicationDescription applicationDescription in applicationDescriptionArray)
            {
                Console.WriteLine();
                Console.WriteLine("Application URI string: {0}", applicationDescription.ApplicationUriString);

                UAApplicationRecordDataType[] applicationRecordArray;
                try
                {
                    applicationRecordArray = globalDiscoveryClient.FindApplications(
                        gdsEndpointDescriptor,
                        applicationDescription.ApplicationUriString);
                }
                catch (UAException uaException)
                {
                    Console.WriteLine("  *** Failure: {0}", uaException.GetBaseException().Message);
                    continue;
                }

                // Display results
                foreach (UAApplicationRecordDataType applicationRecord in applicationRecordArray)
                    Console.WriteLine("  Application ID: {0}", applicationRecord.ApplicationId);
            }


            // Example output:
            //
            //Application URI string: urn:sampleserver
            //  Application ID: nsu=http://opcfoundation.org/UA/GDS/applications/ ;ns=2;g=09ecaa08-6ec6-462c-a214-1e66a3099107
            //
            //Application URI string: urn:alarmconditionserver
            //  Application ID: nsu=http://opcfoundation.org/UA/GDS/applications/ ;ns=2;g=783e1e9a-8036-43b6-928f-97488c460266
            //
            //Application URI string: urn:PC:MultiTargetUADocExamples:5.54.1026.1:neutral:null
            //  Application ID: nsu=http://opcfoundation.org/UA/GDS/applications/ ;ns=2;g=9e700ea5-55a6-4c3c-ba9f-b91c890dc519
            //
            //Application URI string: urn:PC:UADocExamples:5.56.0.16:neutral:null
            //  Application ID: nsu=http://opcfoundation.org/UA/GDS/applications/ ;ns=2;g=e182e28c-086b-4fc7-82c7-70ca7cda3033
            //
            //Application URI string: urn:PC:cscript:5.812.10240.16384
            //  Application ID: nsu=http://opcfoundation.org/UA/GDS/applications/ ;ns=2;g=aec94459-f513-4979-8619-8383555fca61
        }
    }
}

// This example shows how to change the user identity (so-called "user switching") while keeping the same connection (OPC
// UA session).
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using OpcLabs.BaseLib.Aliasing;
using OpcLabs.BaseLib.Aliasing.Extensions;
using OpcLabs.BaseLib.IdentityModel.User;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;
using OpcLabs.EasyOpc.UA.AddressSpace.Standard;
using OpcLabs.EasyOpc.UA.Engine;

namespace UADocExamples.Users
{
    class IdentityChange
    {
        public static void Main1()
        {
            // Note that this example demonstrates the ability to dynamically change the user identity while keeping the
            // same connection. If you want a single user identity, or even multiple user identities at the same time or
            // sequentially without the need to keep the same connection, this example is not for you. In such cases, you can
            // simply specify the user identity directly in the endpoint descriptor, without the use of aliases.


            // This example is designed to work with Unified Automation UaServerNET.exe, which is a demo server from their
            // UA .NET SDK.
            UAEndpointDescriptor endpointDescriptor = "opc.tcp://localhost:48030/";

            // Require a fully secured connection. Prevents passwords from being transferred in clear text.
            endpointDescriptor.EndpointSelectionPolicy = UAEndpointSelectionPolicy.FullySecured;

            // For identity changes, the user identity in the endpoint descriptor must be specified by an alias. The name of
            // the alias (here, "CurrentUser") is up to you.
            endpointDescriptor.UserIdentity.AliasName = "CurrentUser";

            // Set the initial value of the "CurrentUser" alias to an anonymous identity.
            IAliasRepository aliasRepository = AliasingManagement.Instance.AliasRepository;
            aliasRepository.SetAlias("CurrentUser", UserIdentity.CreateAnonymousIdentity());

            // Instantiate the client object.
            var client = new EasyUAClient();

            // Identity changes require an isolated client component, otherwise you will get an error.
            client.Isolated = true;

            // Hook events to the client object.
            client.DataChangeNotification += client_DataChangeNotification;

            Console.WriteLine("Subscribing with anonymous identity...");
            client.SubscribeDataChange(endpointDescriptor, UAVariableIds.Server_ServerStatus_CurrentTime, 1000);

            Console.WriteLine("Processing data change events for 10 seconds...");
            System.Threading.Thread.Sleep(10 * 1000);

            Console.WriteLine("Changing the user identity to 'john' (a known user)...");
            aliasRepository.SetAlias("CurrentUser", UserIdentity.CreateUserNameIdentity("john", "master"));

            Console.WriteLine("Processing data change events for 10 seconds...");
            System.Threading.Thread.Sleep(10 * 1000);

            Console.WriteLine("Attempting to change the user identity to 'unknown', a user that is not known to the server...");
            // This leads to errors in operations and notifications, because the server does not know the user.
            aliasRepository.SetAlias("CurrentUser", UserIdentity.CreateUserNameIdentity("unknown", "123"));

            Console.WriteLine("Processing data change events for 10 seconds...");
            System.Threading.Thread.Sleep(10 * 1000);

            Console.WriteLine("Changing the user identity back to 'john'...");
            // The operations and notifications will no longer give errors, because the server knows and authenticates the
            // user.
            aliasRepository.SetAlias("CurrentUser", UserIdentity.CreateUserNameIdentity("john", "master"));

            Console.WriteLine("Processing data change events for 10 seconds...");
            System.Threading.Thread.Sleep(10 * 1000);

            Console.WriteLine("Unsubscribing...");
            client.UnsubscribeAllMonitoredItems();

            Console.WriteLine("Waiting for 5 seconds...");
            System.Threading.Thread.Sleep(5 * 1000);

            Console.WriteLine("Finished.");
        }
        static void client_DataChangeNotification(object sender, EasyUADataChangeNotificationEventArgs e)
        {
            // Display value.
            if (e.Succeeded)
                Console.WriteLine($"Value: {e.AttributeData.Value}");
            else
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}");
        }
    }
}