// This example shows how to read value of a single node, and display it.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class ReadValue
    {
        public static void Overload1()
        {
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

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

            Console.WriteLine("Obtaining value of a node...");
            object value;
            try
            {
                value = client.ReadValue(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853");
            }
            catch (UAException uaException)
            {
                Console.WriteLine($"*** Failure: {uaException.GetBaseException().Message}");
                return;
            }

            // Display results
            Console.WriteLine($"value: {value}");
        }
    }
}

// This example shows how to read a value from a single node that is an array of UInt16.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class ReadValue
    {
        public static void ArrayOfUInt16()
        {
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

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

            Console.WriteLine("Obtaining value of a node...");
            int[] value;
            try
            {
                // UInt16 is returned as Int32, because UInt16 is not a CLS-compliant type (and is not supported in VB.NET).
                value = (int[])client.ReadValue(endpointDescriptor,
                    "nsu=http://test.org/UA/Data/ ;ns=2;i=10932");   // /Data.Dynamic.Array.UInt16Value
            }
            catch (UAException uaException)
            {
                Console.WriteLine($"*** Failure: {uaException.GetBaseException().Message}");
                return;
            }

            if (!(value is null))
            {
                Console.WriteLine(value[0]);
                Console.WriteLine(value[1]);
                Console.WriteLine(value[2]);
            }

            Console.WriteLine("Finished.");
        }
    }
}

// This example shows how to repeatedly read value of a single node, and display it.

using System;
using System.Threading;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class ReadValue
    {
        public static void Repeated()
        {
            const string endpointDescriptorUrlString =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"
            const string nodeIdExpandedText = "nsu=http://test.org/UA/Data/ ;i=10221";
            // Example settings with Softing dataFEED OPC Suite:
            //  endpointDescriptorUrlString = "opc.tcp://localhost:4980/Softing_dataFEED_OPC_Suite_Configuration1";
            //  nodeIdExpandedText = "nsu=Local%20Items ;s=Local Items.EAK_Test1.EAK_Testwert1_I4";

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

            for (int i = 1; i <= 60; i++)
            {
                Console.Write($"@{DateTime.Now}: ");

                // Obtain value of a node
                object value;
                try
                {
                    value = client.ReadValue(endpointDescriptorUrlString, nodeIdExpandedText);
                }
                catch (UAException uaException)
                {
                    Console.WriteLine($"*** Failure: {uaException.GetBaseException().Message}");
                    return;
                }

                // Display results
                Console.WriteLine($"Read {value}");

                //
                Thread.Sleep(1000);
            }
        }
    }
}

// Shows how to process a data type, displaying some of its properties, recursively.

using System;
using System.Linq;
using OpcLabs.BaseLib.DataTypeModel;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.ComplexData;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.ComplexData._DataType
{
    class Kind
    {
        public static void Main1()
        {
            // Define which server and node we will work with.
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"
            UANodeDescriptor nodeDescriptor = 
                "nsu=http://test.org/UA/Data/ ;i=10239"; // [ObjectsFolder]/Data.Static.Scalar.StructureValue

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

            // Read a node. We know that this node returns complex data, so we can type cast to UAGenericObject.
            UAGenericObject genericObject;
            try
            {
                genericObject = (UAGenericObject)client.ReadValue(endpointDescriptor, nodeDescriptor);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }
            // The data type is in the GenericData.DataType property of the UAGenericObject.
            DataType dataType = genericObject.GenericData.DataType;

            // Process the data type. We will inspect some of its properties, and dump them.
            ProcessDataType(dataType, maximumDepth: 3);
        }
        

        // Process the data type. It can be recursive in itself, so if you do not know the data type you are dealing with, 
        // it is recommended to make safeguards against infinite looping or recursion - here, the maximumDepth.
        public static void ProcessDataType(DataType dataType, int maximumDepth)
        {
            if (maximumDepth == 0)
                return;

            Console.WriteLine();
            Console.WriteLine("dataType.Name: {0}", dataType.Name);

            switch (dataType.Kind)
            {
                case DataTypeKind.Enumeration:
                    Console.WriteLine("The data type is an enumeration.");
                    var enumerationDataType = (EnumerationDataType) dataType;
                    Console.WriteLine("It has {0} enumeration members.", enumerationDataType.EnumerationMembers.Count);
                    Console.WriteLine("The names of the enumeration members are: {0}.",
                        String.Join(", ", enumerationDataType.EnumerationMembers.Select(member => member.Name)));
                    // Here you can process the members, or inspect SizeInBits etc.
                    break;

                case DataTypeKind.Opaque:
                    Console.WriteLine("The data type is opaque.");
                    var opaqueDataType = (OpaqueDataType) dataType;
                    Console.WriteLine("Its size is {0} bits.", opaqueDataType.SizeInBits);
                    // There isn't much more you can learn about an opaque data type (well, it may have Description and 
                    // other common members). It is, after all, opaque...
                    break;

                case DataTypeKind.Primitive:
                    Console.WriteLine("The data type is primitive.");
                    var primitiveDataType = (PrimitiveDataType) dataType;
                    Console.WriteLine("Its .NET value type is \"{0}\".", primitiveDataType.ValueType);
                    // There isn't much more you can learn about the primitive data type.
                    break;

                case DataTypeKind.Sequence:
                    Console.WriteLine("The data type is a sequence.");
                    var sequenceDataType = (SequenceDataType) dataType;
                    Console.WriteLine("Its length is {0} (-1 means that the length can vary).", sequenceDataType.Length);

                    Console.WriteLine("A dump of the element data type follows.");
                    ProcessDataType(sequenceDataType.ElementDataType, maximumDepth - 1);
                    break;

                case DataTypeKind.Structured:
                    Console.WriteLine("The data type is structured.");
                    var structuredDataType = (StructuredDataType) dataType;
                    Console.WriteLine("It has {0} data fields.", structuredDataType.DataFields.Count);
                    Console.WriteLine("The names of the data fields are: {0}.",
                        String.Join(", ", structuredDataType.DataFields.Select(field => field.Name)));

                    Console.WriteLine("A dump of each of the data fields follows.");
                    foreach (DataField dataField in structuredDataType.DataFields)
                    {
                        Console.WriteLine();
                        Console.WriteLine("dataField.Name: {0}", dataField.Name);
                        // Note that every data field also has properties like IsLength, IsOptional, IsSwitch which might 
                        // be of interest, but we are not dumping them here.
                        ProcessDataType(dataField.DataType, maximumDepth - 1);
                    }
                    break;

                case DataTypeKind.Union:
                    Console.WriteLine("The data type is union.");
                    var unionDataType = (UnionDataType)dataType;
                    Console.WriteLine("It has {0} data fields.", unionDataType.DataFields.Count);
                    Console.WriteLine("The names of the data fields are: {0}.",
                        String.Join(", ", unionDataType.DataFields.Select(field => field.Name)));
                    break;
            }
        }
    }
}

// This example shows that either a single client object, or multiple client objects can be used to read values from two
// servers.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class ReadValue
    {
        public static void MultipleServers()
        {
            // Define which servers we will work with.
            UAEndpointDescriptor endpointDescriptor1 =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"
            UAEndpointDescriptor endpointDescriptor2 =
                "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer";



            // Part 1: Use a single client object.
            // This demonstrates the fact that the client objects do *not* represent connections to individual servers.
            // Instead, they are able to maintain connections to multiple servers internally. API method calls on the client
            // object include the server's endpoint descriptor in their arguments, so you can specify a different endpoint
            // with each operation.
            Console.WriteLine();

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

            Console.WriteLine("Obtaining values of nodes using a single client object...");
            object value1, value2;
            try
            {
                // The node Id we are reading returns the product name of the server.
                value1 = client.ReadValue(endpointDescriptor1, "nsu=http://opcfoundation.org/UA/ ;i=2261");
                value2 = client.ReadValue(endpointDescriptor2, "nsu=http://opcfoundation.org/UA/ ;i=2261");
                // Note: For efficiency (reading from the two servers in parallel), it would be better to use the
                // ReadMultipleValues method here, but this example is made for code clarity.
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // Display results
            Console.WriteLine("value1: {0}", value1);
            Console.WriteLine("value2: {0}", value2);



            // Part 2: Use multiple client objects.
            // This demonstrates the fact that it is also possible to use multiple client objects, and on the OPC side, the
            // behavior will be the same as if you had used a single client object. Multiple client objects consume somewhat
            // more resources on the client side, but they come handy if, for example,
            // - you cannot easily pass around the single pre-created client object to various parts in your code, or
            // - you are using subscriptions, and you want to hook separate event handlers for different purposes, or
            // - you need to set something in the instance parameters of the client object differently for different
            // connections.
            Console.WriteLine();

            // Instantiate the client objects.
            var client1 = new EasyUAClient();
            var client2 = new EasyUAClient();

            Console.WriteLine("Obtaining values of nodes using multiple client objects...");
            try
            {
                // The node Id we are reading returns the product name of the server.
                value1 = client1.ReadValue(endpointDescriptor1, "nsu=http://opcfoundation.org/UA/ ;i=2261");
                value2 = client2.ReadValue(endpointDescriptor2, "nsu=http://opcfoundation.org/UA/ ;i=2261");
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // Display results
            Console.WriteLine("value1: {0}", value1);
            Console.WriteLine("value2: {0}", value2);



            // Example output:
            //
            //Obtaining values of nodes using a single client object...
            //value1: OPC UA SDK Samples
            //value2: OPC UA Workshop Samples
            //
            //Obtaining values of nodes using multiple client objects...
            //value1: OPC UA SDK Samples
            //value2: OPC UA Workshop Samples
        }
    }
}