feat(lmxproxy): phase 1 — v2 protocol types and domain model

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lmxproxy/ZB.MOM.WW.LmxProxy.slnx

@@ -3,4 +3,8 @@
     <Project Path="src/ZB.MOM.WW.LmxProxy.Host/ZB.MOM.WW.LmxProxy.Host.csproj" />
     <Project Path="src/ZB.MOM.WW.LmxProxy.Client/ZB.MOM.WW.LmxProxy.Client.csproj" />
   </Folder>
+  <Folder Name="/tests/">
+    <Project Path="tests/ZB.MOM.WW.LmxProxy.Host.Tests/ZB.MOM.WW.LmxProxy.Host.Tests.csproj" />
+    <Project Path="tests/ZB.MOM.WW.LmxProxy.Client.Tests/ZB.MOM.WW.LmxProxy.Client.Tests.csproj" />
+  </Folder>
 </Solution>

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/ConnectionState.cs

@@ -0,0 +1,49 @@
+using System;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+/// <summary>
+/// Represents the connection state of an LmxProxy client.
+/// </summary>
+public enum ConnectionState
+{
+	/// <summary>Not connected to the server.</summary>
+	Disconnected,
+
+	/// <summary>Connection attempt in progress.</summary>
+	Connecting,
+
+	/// <summary>Connected and ready for operations.</summary>
+	Connected,
+
+	/// <summary>Graceful disconnect in progress.</summary>
+	Disconnecting,
+
+	/// <summary>Connection failed with an error.</summary>
+	Error,
+
+	/// <summary>Attempting to re-establish a lost connection.</summary>
+	Reconnecting
+}
+
+/// <summary>
+/// Event arguments for connection state change notifications.
+/// </summary>
+public class ConnectionStateChangedEventArgs : EventArgs
+{
+	/// <summary>The previous connection state.</summary>
+	public ConnectionState OldState { get; }
+
+	/// <summary>The new connection state.</summary>
+	public ConnectionState NewState { get; }
+
+	/// <summary>Optional message describing the state change (e.g., error details).</summary>
+	public string? Message { get; }
+
+	public ConnectionStateChangedEventArgs(ConnectionState oldState, ConnectionState newState, string? message = null)
+	{
+		OldState = oldState;
+		NewState = newState;
+		Message = message;
+	}
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/Quality.cs

@@ -0,0 +1,118 @@
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+/// <summary>
+/// OPC-style quality codes for SCADA data values.
+/// Based on OPC DA quality encoding as a single byte:
+/// bits 7–6 = major (00=Bad, 01=Uncertain, 11=Good),
+/// bits 5–2 = substatus, bits 1–0 = limit (00=None, 01=Low, 10=High, 11=Constant).
+/// </summary>
+public enum Quality : byte
+{
+	/// <summary>Bad – non-specific.</summary>
+	Bad = 0,
+
+	/// <summary>Bad – configuration error in the server.</summary>
+	Bad_ConfigError = 4,
+
+	/// <summary>Bad – input source is not connected.</summary>
+	Bad_NotConnected = 8,
+
+	/// <summary>Bad – device failure detected.</summary>
+	Bad_DeviceFailure = 12,
+
+	/// <summary>Bad – sensor failure detected.</summary>
+	Bad_SensorFailure = 16,
+
+	/// <summary>Bad – last known value (communication lost, value stale).</summary>
+	Bad_LastKnownValue = 20,
+
+	/// <summary>Bad – communication failure.</summary>
+	Bad_CommFailure = 24,
+
+	/// <summary>Bad – item is out of service.</summary>
+	Bad_OutOfService = 28,
+
+	/// <summary>Uncertain – non-specific.</summary>
+	Uncertain = 64,
+
+	/// <summary>Uncertain – non-specific, low limited.</summary>
+	Uncertain_LowLimited = 65,
+
+	/// <summary>Uncertain – non-specific, high limited.</summary>
+	Uncertain_HighLimited = 66,
+
+	/// <summary>Uncertain – non-specific, constant.</summary>
+	Uncertain_Constant = 67,
+
+	/// <summary>Uncertain – last usable value.</summary>
+	Uncertain_LastUsable = 68,
+
+	/// <summary>Uncertain – last usable value, low limited.</summary>
+	Uncertain_LastUsable_LL = 69,
+
+	/// <summary>Uncertain – last usable value, high limited.</summary>
+	Uncertain_LastUsable_HL = 70,
+
+	/// <summary>Uncertain – last usable value, constant.</summary>
+	Uncertain_LastUsable_Cnst = 71,
+
+	/// <summary>Uncertain – sensor not accurate.</summary>
+	Uncertain_SensorNotAcc = 80,
+
+	/// <summary>Uncertain – sensor not accurate, low limited.</summary>
+	Uncertain_SensorNotAcc_LL = 81,
+
+	/// <summary>Uncertain – sensor not accurate, high limited.</summary>
+	Uncertain_SensorNotAcc_HL = 82,
+
+	/// <summary>Uncertain – sensor not accurate, constant.</summary>
+	Uncertain_SensorNotAcc_C = 83,
+
+	/// <summary>Uncertain – engineering units exceeded.</summary>
+	Uncertain_EuExceeded = 84,
+
+	/// <summary>Uncertain – engineering units exceeded, low limited.</summary>
+	Uncertain_EuExceeded_LL = 85,
+
+	/// <summary>Uncertain – engineering units exceeded, high limited.</summary>
+	Uncertain_EuExceeded_HL = 86,
+
+	/// <summary>Uncertain – engineering units exceeded, constant.</summary>
+	Uncertain_EuExceeded_C = 87,
+
+	/// <summary>Uncertain – sub-normal operating conditions.</summary>
+	Uncertain_SubNormal = 88,
+
+	/// <summary>Uncertain – sub-normal, low limited.</summary>
+	Uncertain_SubNormal_LL = 89,
+
+	/// <summary>Uncertain – sub-normal, high limited.</summary>
+	Uncertain_SubNormal_HL = 90,
+
+	/// <summary>Uncertain – sub-normal, constant.</summary>
+	Uncertain_SubNormal_C = 91,
+
+	/// <summary>Good – non-specific.</summary>
+	Good = 192,
+
+	/// <summary>Good – low limited.</summary>
+	Good_LowLimited = 193,
+
+	/// <summary>Good – high limited.</summary>
+	Good_HighLimited = 194,
+
+	/// <summary>Good – constant.</summary>
+	Good_Constant = 195,
+
+	/// <summary>Good – local override active.</summary>
+	Good_LocalOverride = 216,
+
+	/// <summary>Good – local override active, low limited.</summary>
+	Good_LocalOverride_LL = 217,
+
+	/// <summary>Good – local override active, high limited.</summary>
+	Good_LocalOverride_HL = 218,
+
+	/// <summary>Good – local override active, constant.</summary>
+	Good_LocalOverride_C = 219
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/QualityExtensions.cs

@@ -0,0 +1,8 @@
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+public static class QualityExtensions
+{
+	public static bool IsGood(this Quality q) => (byte)q >= 128;
+	public static bool IsUncertain(this Quality q) => (byte)q is >= 64 and < 128;
+	public static bool IsBad(this Quality q) => (byte)q < 64;
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/ScadaContracts.cs

@@ -0,0 +1,444 @@
+using System.Collections.Generic;
+using System.Runtime.Serialization;
+using System.ServiceModel;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+// ────────────────────────────────────────────────────────────────
+// Service contract
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>
+/// Code-first gRPC service contract for SCADA operations.
+/// </summary>
+[ServiceContract(Name = "scada.ScadaService")]
+public interface IScadaService
+{
+	/// <summary>Establishes a connection with the SCADA service.</summary>
+	ValueTask<ConnectResponse> ConnectAsync(ConnectRequest request);
+
+	/// <summary>Terminates a SCADA service connection.</summary>
+	ValueTask<DisconnectResponse> DisconnectAsync(DisconnectRequest request);
+
+	/// <summary>Retrieves the current state of a SCADA connection.</summary>
+	ValueTask<GetConnectionStateResponse> GetConnectionStateAsync(GetConnectionStateRequest request);
+
+	/// <summary>Reads a single tag value from the SCADA system.</summary>
+	ValueTask<ReadResponse> ReadAsync(ReadRequest request);
+
+	/// <summary>Reads multiple tag values from the SCADA system in a batch operation.</summary>
+	ValueTask<ReadBatchResponse> ReadBatchAsync(ReadBatchRequest request);
+
+	/// <summary>Writes a single value to a tag in the SCADA system.</summary>
+	ValueTask<WriteResponse> WriteAsync(WriteRequest request);
+
+	/// <summary>Writes multiple values to tags in the SCADA system in a batch operation.</summary>
+	ValueTask<WriteBatchResponse> WriteBatchAsync(WriteBatchRequest request);
+
+	/// <summary>Writes multiple values and waits for a completion flag before returning.</summary>
+	ValueTask<WriteBatchAndWaitResponse> WriteBatchAndWaitAsync(WriteBatchAndWaitRequest request);
+
+	/// <summary>Subscribes to real-time value changes from specified tags.</summary>
+	IAsyncEnumerable<VtqMessage> SubscribeAsync(SubscribeRequest request, CancellationToken cancellationToken = default);
+
+	/// <summary>Validates an API key for authentication.</summary>
+	ValueTask<CheckApiKeyResponse> CheckApiKeyAsync(CheckApiKeyRequest request);
+}
+
+// ────────────────────────────────────────────────────────────────
+// VTQ message
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>
+/// Value-Timestamp-Quality message transmitted over gRPC.
+/// All values are string-encoded; timestamps are UTC ticks.
+/// </summary>
+[DataContract]
+public class VtqMessage
+{
+	/// <summary>Tag address.</summary>
+	[DataMember(Order = 1)]
+	public string Tag { get; set; } = string.Empty;
+
+	/// <summary>Value encoded as a string.</summary>
+	[DataMember(Order = 2)]
+	public string Value { get; set; } = string.Empty;
+
+	/// <summary>UTC timestamp as DateTime.Ticks (100ns intervals since 0001-01-01).</summary>
+	[DataMember(Order = 3)]
+	public long TimestampUtcTicks { get; set; }
+
+	/// <summary>Quality string: "Good", "Uncertain", or "Bad".</summary>
+	[DataMember(Order = 4)]
+	public string Quality { get; set; } = string.Empty;
+}
+
+// ────────────────────────────────────────────────────────────────
+// Connect
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to establish a session with the proxy server.</summary>
+[DataContract]
+public class ConnectRequest
+{
+	/// <summary>Client identifier (e.g., "ScadaLink-{guid}").</summary>
+	[DataMember(Order = 1)]
+	public string ClientId { get; set; } = string.Empty;
+
+	/// <summary>API key for authentication (empty if none required).</summary>
+	[DataMember(Order = 2)]
+	public string ApiKey { get; set; } = string.Empty;
+}
+
+/// <summary>Response from a Connect call.</summary>
+[DataContract]
+public class ConnectResponse
+{
+	/// <summary>Whether the connection was established successfully.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Status or error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+
+	/// <summary>Session ID (32-char hex GUID). Only valid when <see cref="Success"/> is <c>true</c>.</summary>
+	[DataMember(Order = 3)]
+	public string SessionId { get; set; } = string.Empty;
+}
+
+// ────────────────────────────────────────────────────────────────
+// Disconnect
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to terminate a session.</summary>
+[DataContract]
+public class DisconnectRequest
+{
+	/// <summary>Active session ID to disconnect.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+}
+
+/// <summary>Response from a Disconnect call.</summary>
+[DataContract]
+public class DisconnectResponse
+{
+	/// <summary>Whether the disconnect succeeded.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Status or error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+}
+
+// ────────────────────────────────────────────────────────────────
+// GetConnectionState
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to query connection state for a session.</summary>
+[DataContract]
+public class GetConnectionStateRequest
+{
+	/// <summary>Session ID to query.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+}
+
+/// <summary>Response with connection state information.</summary>
+[DataContract]
+public class GetConnectionStateResponse
+{
+	/// <summary>Whether the session is currently connected.</summary>
+	[DataMember(Order = 1)]
+	public bool IsConnected { get; set; }
+
+	/// <summary>Client identifier for this session.</summary>
+	[DataMember(Order = 2)]
+	public string ClientId { get; set; } = string.Empty;
+
+	/// <summary>UTC ticks when the connection was established.</summary>
+	[DataMember(Order = 3)]
+	public long ConnectedSinceUtcTicks { get; set; }
+}
+
+// ────────────────────────────────────────────────────────────────
+// Read
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to read a single tag.</summary>
+[DataContract]
+public class ReadRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag address to read.</summary>
+	[DataMember(Order = 2)]
+	public string Tag { get; set; } = string.Empty;
+}
+
+/// <summary>Response from a single-tag Read call.</summary>
+[DataContract]
+public class ReadResponse
+{
+	/// <summary>Whether the read succeeded.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Error message if the read failed.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+
+	/// <summary>The value-timestamp-quality result.</summary>
+	[DataMember(Order = 3)]
+	public VtqMessage? Vtq { get; set; }
+}
+
+// ────────────────────────────────────────────────────────────────
+// ReadBatch
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to read multiple tags in a single round-trip.</summary>
+[DataContract]
+public class ReadBatchRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag addresses to read.</summary>
+	[DataMember(Order = 2)]
+	public List<string> Tags { get; set; } = [];
+}
+
+/// <summary>Response from a batch Read call.</summary>
+[DataContract]
+public class ReadBatchResponse
+{
+	/// <summary>False if any tag read failed.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+
+	/// <summary>VTQ results in the same order as the request tags.</summary>
+	[DataMember(Order = 3)]
+	public List<VtqMessage> Vtqs { get; set; } = [];
+}
+
+// ────────────────────────────────────────────────────────────────
+// Write
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to write a single tag value.</summary>
+[DataContract]
+public class WriteRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag address to write.</summary>
+	[DataMember(Order = 2)]
+	public string Tag { get; set; } = string.Empty;
+
+	/// <summary>Value as a string (parsed server-side).</summary>
+	[DataMember(Order = 3)]
+	public string Value { get; set; } = string.Empty;
+}
+
+/// <summary>Response from a single-tag Write call.</summary>
+[DataContract]
+public class WriteResponse
+{
+	/// <summary>Whether the write succeeded.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Status or error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+}
+
+// ────────────────────────────────────────────────────────────────
+// WriteItem / WriteResult
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>A single tag-value pair for batch write operations.</summary>
+[DataContract]
+public class WriteItem
+{
+	/// <summary>Tag address.</summary>
+	[DataMember(Order = 1)]
+	public string Tag { get; set; } = string.Empty;
+
+	/// <summary>Value as a string.</summary>
+	[DataMember(Order = 2)]
+	public string Value { get; set; } = string.Empty;
+}
+
+/// <summary>Per-item result from a batch write operation.</summary>
+[DataContract]
+public class WriteResult
+{
+	/// <summary>Tag address that was written.</summary>
+	[DataMember(Order = 1)]
+	public string Tag { get; set; } = string.Empty;
+
+	/// <summary>Whether the individual write succeeded.</summary>
+	[DataMember(Order = 2)]
+	public bool Success { get; set; }
+
+	/// <summary>Error message for this item, if any.</summary>
+	[DataMember(Order = 3)]
+	public string Message { get; set; } = string.Empty;
+}
+
+// ────────────────────────────────────────────────────────────────
+// WriteBatch
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to write multiple tag values in a single round-trip.</summary>
+[DataContract]
+public class WriteBatchRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag-value pairs to write.</summary>
+	[DataMember(Order = 2)]
+	public List<WriteItem> Items { get; set; } = [];
+}
+
+/// <summary>Response from a batch Write call.</summary>
+[DataContract]
+public class WriteBatchResponse
+{
+	/// <summary>Overall success — false if any item failed.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Status or error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+
+	/// <summary>Per-item write results.</summary>
+	[DataMember(Order = 3)]
+	public List<WriteResult> Results { get; set; } = [];
+}
+
+// ────────────────────────────────────────────────────────────────
+// WriteBatchAndWait
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>
+/// Request to write multiple tag values then poll a flag tag
+/// until it matches an expected value or the timeout expires.
+/// </summary>
+[DataContract]
+public class WriteBatchAndWaitRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag-value pairs to write.</summary>
+	[DataMember(Order = 2)]
+	public List<WriteItem> Items { get; set; } = [];
+
+	/// <summary>Tag to poll after writes complete.</summary>
+	[DataMember(Order = 3)]
+	public string FlagTag { get; set; } = string.Empty;
+
+	/// <summary>Expected value for the flag tag (string comparison).</summary>
+	[DataMember(Order = 4)]
+	public string FlagValue { get; set; } = string.Empty;
+
+	/// <summary>Timeout in milliseconds (default 5000 if &lt;= 0).</summary>
+	[DataMember(Order = 5)]
+	public int TimeoutMs { get; set; }
+
+	/// <summary>Poll interval in milliseconds (default 100 if &lt;= 0).</summary>
+	[DataMember(Order = 6)]
+	public int PollIntervalMs { get; set; }
+}
+
+/// <summary>Response from a WriteBatchAndWait call.</summary>
+[DataContract]
+public class WriteBatchAndWaitResponse
+{
+	/// <summary>Overall operation success.</summary>
+	[DataMember(Order = 1)]
+	public bool Success { get; set; }
+
+	/// <summary>Status or error message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+
+	/// <summary>Per-item write results.</summary>
+	[DataMember(Order = 3)]
+	public List<WriteResult> WriteResults { get; set; } = [];
+
+	/// <summary>Whether the flag tag matched the expected value before timeout.</summary>
+	[DataMember(Order = 4)]
+	public bool FlagReached { get; set; }
+
+	/// <summary>Total elapsed time in milliseconds.</summary>
+	[DataMember(Order = 5)]
+	public int ElapsedMs { get; set; }
+}
+
+// ────────────────────────────────────────────────────────────────
+// Subscribe
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to subscribe to value change notifications on one or more tags.</summary>
+[DataContract]
+public class SubscribeRequest
+{
+	/// <summary>Valid session ID.</summary>
+	[DataMember(Order = 1)]
+	public string SessionId { get; set; } = string.Empty;
+
+	/// <summary>Tag addresses to monitor.</summary>
+	[DataMember(Order = 2)]
+	public List<string> Tags { get; set; } = [];
+
+	/// <summary>Backend sampling interval in milliseconds.</summary>
+	[DataMember(Order = 3)]
+	public int SamplingMs { get; set; }
+}
+
+// ────────────────────────────────────────────────────────────────
+// CheckApiKey
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>Request to validate an API key without creating a session.</summary>
+[DataContract]
+public class CheckApiKeyRequest
+{
+	/// <summary>API key to validate.</summary>
+	[DataMember(Order = 1)]
+	public string ApiKey { get; set; } = string.Empty;
+}
+
+/// <summary>Response from an API key validation check.</summary>
+[DataContract]
+public class CheckApiKeyResponse
+{
+	/// <summary>Whether the API key is valid.</summary>
+	[DataMember(Order = 1)]
+	public bool IsValid { get; set; }
+
+	/// <summary>Validation message.</summary>
+	[DataMember(Order = 2)]
+	public string Message { get; set; } = string.Empty;
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/Vtq.cs

@@ -0,0 +1,27 @@
+using System;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+/// <summary>
+/// Value, Timestamp, and Quality structure for SCADA data.
+/// </summary>
+/// <param name="Value">The value.</param>
+/// <param name="Timestamp">The timestamp when the value was read.</param>
+/// <param name="Quality">The quality of the value.</param>
+public readonly record struct Vtq(object? Value, DateTime Timestamp, Quality Quality)
+{
+	/// <summary>Creates a new VTQ with the specified value and quality, using the current UTC timestamp.</summary>
+	public static Vtq New(object? value, Quality quality) => new(value, DateTime.UtcNow, quality);
+
+	/// <summary>Creates a new VTQ with the specified value, timestamp, and quality.</summary>
+	public static Vtq New(object? value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
+
+	/// <summary>Creates a Good-quality VTQ with the current UTC time.</summary>
+	public static Vtq Good(object? value) => new(value, DateTime.UtcNow, Quality.Good);
+
+	/// <summary>Creates a Bad-quality VTQ with the current UTC time.</summary>
+	public static Vtq Bad(object? value = null) => new(value, DateTime.UtcNow, Quality.Bad);
+
+	/// <summary>Creates an Uncertain-quality VTQ with the current UTC time.</summary>
+	public static Vtq Uncertain(object? value) => new(value, DateTime.UtcNow, Quality.Uncertain);
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/ZB.MOM.WW.LmxProxy.Client.csproj

@@ -0,0 +1,27 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
+    <RootNamespace>ZB.MOM.WW.LmxProxy.Client</RootNamespace>
+    <AssemblyName>ZB.MOM.WW.LmxProxy.Client</AssemblyName>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <IsPackable>true</IsPackable>
+    <Description>gRPC client library for LmxProxy service</Description>
+    <PlatformTarget>AnyCPU</PlatformTarget>
+    <Platforms>AnyCPU</Platforms>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Grpc.Core.Api" Version="2.71.0" />
+    <PackageReference Include="Grpc.Net.Client" Version="2.71.0" />
+    <PackageReference Include="protobuf-net.Grpc" Version="1.2.5" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="10.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="10.0.0" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="10.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.0" />
+    <PackageReference Include="Polly" Version="8.5.2" />
+  </ItemGroup>
+
+</Project>

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/ConnectionState.cs

@@ -0,0 +1,38 @@
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Represents the state of a SCADA client connection.
+    /// </summary>
+    public enum ConnectionState
+    {
+        /// <summary>
+        ///     The client is disconnected.
+        /// </summary>
+        Disconnected,
+
+        /// <summary>
+        ///     The client is in the process of connecting.
+        /// </summary>
+        Connecting,
+
+        /// <summary>
+        ///     The client is connected.
+        /// </summary>
+        Connected,
+
+        /// <summary>
+        ///     The client is in the process of disconnecting.
+        /// </summary>
+        Disconnecting,
+
+        /// <summary>
+        ///     The client encountered an error.
+        /// </summary>
+        Error,
+
+        /// <summary>
+        ///     The client is reconnecting after a connection loss.
+        /// </summary>
+        Reconnecting
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/ConnectionStateChangedEventArgs.cs

@@ -0,0 +1,45 @@
+using System;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Event arguments for SCADA client connection state changes.
+    /// </summary>
+    public class ConnectionStateChangedEventArgs : EventArgs
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="ConnectionStateChangedEventArgs" /> class.
+        /// </summary>
+        /// <param name="previousState">The previous connection state.</param>
+        /// <param name="currentState">The current connection state.</param>
+        /// <param name="message">Optional message providing additional information about the state change.</param>
+        public ConnectionStateChangedEventArgs(ConnectionState previousState, ConnectionState currentState,
+            string? message = null)
+        {
+            PreviousState = previousState;
+            CurrentState = currentState;
+            Timestamp = DateTime.UtcNow;
+            Message = message;
+        }
+
+        /// <summary>
+        ///     Gets the previous connection state.
+        /// </summary>
+        public ConnectionState PreviousState { get; }
+
+        /// <summary>
+        ///     Gets the current connection state.
+        /// </summary>
+        public ConnectionState CurrentState { get; }
+
+        /// <summary>
+        ///     Gets the timestamp when the state change occurred.
+        /// </summary>
+        public DateTime Timestamp { get; }
+
+        /// <summary>
+        ///     Gets additional information about the state change, such as error messages.
+        /// </summary>
+        public string? Message { get; }
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/IScadaClient.cs

@@ -0,0 +1,104 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Interface for SCADA system clients.
+    /// </summary>
+    public interface IScadaClient : IAsyncDisposable
+    {
+        /// <summary>
+        ///     Gets the connection status.
+        /// </summary>
+        bool IsConnected { get; }
+
+        /// <summary>
+        ///     Gets the current connection state.
+        /// </summary>
+        ConnectionState ConnectionState { get; }
+
+        /// <summary>
+        ///     Occurs when the connection state changes.
+        /// </summary>
+        event EventHandler<ConnectionStateChangedEventArgs> ConnectionStateChanged;
+
+        /// <summary>
+        ///     Connects to the SCADA system.
+        /// </summary>
+        /// <param name="ct">Cancellation token.</param>
+        Task ConnectAsync(CancellationToken ct = default);
+
+        /// <summary>
+        ///     Disconnects from the SCADA system.
+        /// </summary>
+        /// <param name="ct">Cancellation token.</param>
+        Task DisconnectAsync(CancellationToken ct = default);
+
+        /// <summary>
+        ///     Reads a single tag value from the SCADA system.
+        /// </summary>
+        /// <param name="address">The tag address.</param>
+        /// <param name="ct">Cancellation token.</param>
+        /// <returns>The value, timestamp, and quality.</returns>
+        Task<Vtq> ReadAsync(string address, CancellationToken ct = default);
+
+        /// <summary>
+        ///     Reads multiple tag values from the SCADA system.
+        /// </summary>
+        /// <param name="addresses">The tag addresses.</param>
+        /// <param name="ct">Cancellation token.</param>
+        /// <returns>Dictionary of address to VTQ values.</returns>
+        Task<IReadOnlyDictionary<string, Vtq>>
+            ReadBatchAsync(IEnumerable<string> addresses, CancellationToken ct = default);
+
+        /// <summary>
+        ///     Writes a single tag value to the SCADA system.
+        /// </summary>
+        /// <param name="address">The tag address.</param>
+        /// <param name="value">The value to write.</param>
+        /// <param name="ct">Cancellation token.</param>
+        Task WriteAsync(string address, object value, CancellationToken ct = default);
+
+        /// <summary>
+        ///     Writes multiple tag values to the SCADA system.
+        /// </summary>
+        /// <param name="values">Dictionary of address to value.</param>
+        /// <param name="ct">Cancellation token.</param>
+        Task WriteBatchAsync(IReadOnlyDictionary<string, object> values, CancellationToken ct = default);
+
+        /// <summary>
+        ///     Writes a batch of tag values and a flag tag, then waits for a response tag to
+        ///     equal the expected value.
+        /// </summary>
+        /// <param name="values">The regular tag values to write.</param>
+        /// <param name="flagAddress">The address of the flag tag to write.</param>
+        /// <param name="flagValue">The value to write to the flag tag.</param>
+        /// <param name="responseAddress">The address of the response tag to monitor.</param>
+        /// <param name="responseValue">The expected value of the response tag.</param>
+        /// <param name="ct">Cancellation token controlling the wait.</param>
+        /// <returns>
+        ///     <c>true</c> if the response value was observed before cancellation;
+        ///     otherwise <c>false</c>.
+        /// </returns>
+        Task<bool> WriteBatchAndWaitAsync(
+            IReadOnlyDictionary<string, object> values,
+            string flagAddress,
+            object flagValue,
+            string responseAddress,
+            object responseValue,
+            CancellationToken ct = default);
+
+        /// <summary>
+        ///     Subscribes to value changes for specified addresses.
+        /// </summary>
+        /// <param name="addresses">The tag addresses to monitor.</param>
+        /// <param name="callback">Callback for value changes.</param>
+        /// <param name="ct">Cancellation token.</param>
+        /// <returns>Subscription handle for unsubscribing.</returns>
+        Task<IAsyncDisposable> SubscribeAsync(IEnumerable<string> addresses, Action<string, Vtq> callback,
+            CancellationToken ct = default);
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/Quality.cs

@@ -0,0 +1,124 @@
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     OPC quality codes mapped to domain-level values.
+    ///     The byte value matches the low-order byte of the OPC UA StatusCode,
+    ///     so it can be persisted or round-tripped without translation.
+    /// </summary>
+    public enum Quality : byte
+    {
+        // ─────────────── Bad family (0-31) ───────────────
+        /// <summary>0x00 – Bad [Non-Specific]</summary>
+        Bad = 0,
+
+        /// <summary>0x01 – Unknown quality value</summary>
+        Unknown = 1,
+
+        /// <summary>0x04 – Bad [Configuration Error]</summary>
+        Bad_ConfigError = 4,
+
+        /// <summary>0x08 – Bad [Not Connected]</summary>
+        Bad_NotConnected = 8,
+
+        /// <summary>0x0C – Bad [Device Failure]</summary>
+        Bad_DeviceFailure = 12,
+
+        /// <summary>0x10 – Bad [Sensor Failure]</summary>
+        Bad_SensorFailure = 16,
+
+        /// <summary>0x14 – Bad [Last Known Value]</summary>
+        Bad_LastKnownValue = 20,
+
+        /// <summary>0x18 – Bad [Communication Failure]</summary>
+        Bad_CommFailure = 24,
+
+        /// <summary>0x1C – Bad [Out of Service]</summary>
+        Bad_OutOfService = 28,
+
+        // ──────────── Uncertain family (64-95) ───────────
+        /// <summary>0x40 – Uncertain [Non-Specific]</summary>
+        Uncertain = 64,
+
+        /// <summary>0x41 – Uncertain [Non-Specific] (Low Limited)</summary>
+        Uncertain_LowLimited = 65,
+
+        /// <summary>0x42 – Uncertain [Non-Specific] (High Limited)</summary>
+        Uncertain_HighLimited = 66,
+
+        /// <summary>0x43 – Uncertain [Non-Specific] (Constant)</summary>
+        Uncertain_Constant = 67,
+
+        /// <summary>0x44 – Uncertain [Last Usable]</summary>
+        Uncertain_LastUsable = 68,
+
+        /// <summary>0x45 – Uncertain [Last Usable] (Low Limited)</summary>
+        Uncertain_LastUsable_LL = 69,
+
+        /// <summary>0x46 – Uncertain [Last Usable] (High Limited)</summary>
+        Uncertain_LastUsable_HL = 70,
+
+        /// <summary>0x47 – Uncertain [Last Usable] (Constant)</summary>
+        Uncertain_LastUsable_Cnst = 71,
+
+        /// <summary>0x50 – Uncertain [Sensor Not Accurate]</summary>
+        Uncertain_SensorNotAcc = 80,
+
+        /// <summary>0x51 – Uncertain [Sensor Not Accurate] (Low Limited)</summary>
+        Uncertain_SensorNotAcc_LL = 81,
+
+        /// <summary>0x52 – Uncertain [Sensor Not Accurate] (High Limited)</summary>
+        Uncertain_SensorNotAcc_HL = 82,
+
+        /// <summary>0x53 – Uncertain [Sensor Not Accurate] (Constant)</summary>
+        Uncertain_SensorNotAcc_C = 83,
+
+        /// <summary>0x54 – Uncertain [EU Exceeded]</summary>
+        Uncertain_EuExceeded = 84,
+
+        /// <summary>0x55 – Uncertain [EU Exceeded] (Low Limited)</summary>
+        Uncertain_EuExceeded_LL = 85,
+
+        /// <summary>0x56 – Uncertain [EU Exceeded] (High Limited)</summary>
+        Uncertain_EuExceeded_HL = 86,
+
+        /// <summary>0x57 – Uncertain [EU Exceeded] (Constant)</summary>
+        Uncertain_EuExceeded_C = 87,
+
+        /// <summary>0x58 – Uncertain [Sub-Normal]</summary>
+        Uncertain_SubNormal = 88,
+
+        /// <summary>0x59 – Uncertain [Sub-Normal] (Low Limited)</summary>
+        Uncertain_SubNormal_LL = 89,
+
+        /// <summary>0x5A – Uncertain [Sub-Normal] (High Limited)</summary>
+        Uncertain_SubNormal_HL = 90,
+
+        /// <summary>0x5B – Uncertain [Sub-Normal] (Constant)</summary>
+        Uncertain_SubNormal_C = 91,
+
+        // ─────────────── Good family (192-219) ────────────
+        /// <summary>0xC0 – Good [Non-Specific]</summary>
+        Good = 192,
+
+        /// <summary>0xC1 – Good [Non-Specific] (Low Limited)</summary>
+        Good_LowLimited = 193,
+
+        /// <summary>0xC2 – Good [Non-Specific] (High Limited)</summary>
+        Good_HighLimited = 194,
+
+        /// <summary>0xC3 – Good [Non-Specific] (Constant)</summary>
+        Good_Constant = 195,
+
+        /// <summary>0xD8 – Good [Local Override]</summary>
+        Good_LocalOverride = 216,
+
+        /// <summary>0xD9 – Good [Local Override] (Low Limited)</summary>
+        Good_LocalOverride_LL = 217,
+
+        /// <summary>0xDA – Good [Local Override] (High Limited)</summary>
+        Good_LocalOverride_HL = 218,
+
+        /// <summary>0xDB – Good [Local Override] (Constant)</summary>
+        Good_LocalOverride_C = 219
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/Vtq.cs

@@ -0,0 +1,129 @@
+using System;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Value, Timestamp, and Quality structure for SCADA data.
+    /// </summary>
+    public readonly struct Vtq : IEquatable<Vtq>
+    {
+        /// <summary>
+        ///     Gets the value.
+        /// </summary>
+        public object? Value { get; }
+
+        /// <summary>
+        ///     Gets the timestamp when the value was read.
+        /// </summary>
+        public DateTime Timestamp { get; }
+
+        /// <summary>
+        ///     Gets the quality of the value.
+        /// </summary>
+        public Quality Quality { get; }
+
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="Vtq" /> struct.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <param name="timestamp">The timestamp when the value was read.</param>
+        /// <param name="quality">The quality of the value.</param>
+        public Vtq(object? value, DateTime timestamp, Quality quality)
+        {
+            Value = value;
+            Timestamp = timestamp;
+            Quality = quality;
+        }
+
+        /// <summary>
+        ///     Creates a new <see cref="Vtq" /> instance with the specified value and quality, using the current UTC timestamp.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <param name="quality">The quality of the value.</param>
+        /// <returns>A new <see cref="Vtq" /> instance.</returns>
+        public static Vtq New(object value, Quality quality) => new(value, DateTime.UtcNow, quality);
+
+        /// <summary>
+        ///     Creates a new <see cref="Vtq" /> instance with the specified value, timestamp, and quality.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <param name="timestamp">The timestamp when the value was read.</param>
+        /// <param name="quality">The quality of the value.</param>
+        /// <returns>A new <see cref="Vtq" /> instance.</returns>
+        public static Vtq New(object value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
+
+        /// <summary>
+        ///     Creates a <see cref="Vtq" /> instance with good quality and the current UTC timestamp.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <returns>A new <see cref="Vtq" /> instance with good quality.</returns>
+        public static Vtq Good(object value) => new(value, DateTime.UtcNow, Quality.Good);
+
+        /// <summary>
+        ///     Creates a <see cref="Vtq" /> instance with bad quality and the current UTC timestamp.
+        /// </summary>
+        /// <param name="value">The value. Optional.</param>
+        /// <returns>A new <see cref="Vtq" /> instance with bad quality.</returns>
+        public static Vtq Bad(object? value = null) => new(value, DateTime.UtcNow, Quality.Bad);
+
+        /// <summary>
+        ///     Creates a <see cref="Vtq" /> instance with uncertain quality and the current UTC timestamp.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <returns>A new <see cref="Vtq" /> instance with uncertain quality.</returns>
+        public static Vtq Uncertain(object value) => new(value, DateTime.UtcNow, Quality.Uncertain);
+
+        /// <summary>
+        ///     Determines whether the specified <see cref="Vtq" /> is equal to the current <see cref="Vtq" />.
+        /// </summary>
+        /// <param name="other">The <see cref="Vtq" /> to compare with the current <see cref="Vtq" />.</param>
+        /// <returns>true if the specified <see cref="Vtq" /> is equal to the current <see cref="Vtq" />; otherwise, false.</returns>
+        public bool Equals(Vtq other) =>
+            Equals(Value, other.Value) && Timestamp.Equals(other.Timestamp) && Quality == other.Quality;
+
+        /// <summary>
+        ///     Determines whether the specified object is equal to the current <see cref="Vtq" />.
+        /// </summary>
+        /// <param name="obj">The object to compare with the current <see cref="Vtq" />.</param>
+        /// <returns>true if the specified object is equal to the current <see cref="Vtq" />; otherwise, false.</returns>
+        public override bool Equals(object obj) => obj is Vtq other && Equals(other);
+
+        /// <summary>
+        ///     Returns the hash code for this instance.
+        /// </summary>
+        /// <returns>A 32-bit signed integer hash code.</returns>
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                int hashCode = Value != null ? Value.GetHashCode() : 0;
+                hashCode = (hashCode * 397) ^ Timestamp.GetHashCode();
+                hashCode = (hashCode * 397) ^ (int)Quality;
+                return hashCode;
+            }
+        }
+
+        /// <summary>
+        ///     Returns a string that represents the current object.
+        /// </summary>
+        /// <returns>A string that represents the current object.</returns>
+        public override string ToString() =>
+            $"{{Value={Value}, Timestamp={Timestamp:yyyy-MM-dd HH:mm:ss.fff}, Quality={Quality}}}";
+
+        /// <summary>
+        ///     Determines whether two specified instances of <see cref="Vtq" /> are equal.
+        /// </summary>
+        /// <param name="left">The first <see cref="Vtq" /> to compare.</param>
+        /// <param name="right">The second <see cref="Vtq" /> to compare.</param>
+        /// <returns>true if left and right are equal; otherwise, false.</returns>
+        public static bool operator ==(Vtq left, Vtq right) => left.Equals(right);
+
+        /// <summary>
+        ///     Determines whether two specified instances of <see cref="Vtq" /> are not equal.
+        /// </summary>
+        /// <param name="left">The first <see cref="Vtq" /> to compare.</param>
+        /// <param name="right">The second <see cref="Vtq" /> to compare.</param>
+        /// <returns>true if left and right are not equal; otherwise, false.</returns>
+        public static bool operator !=(Vtq left, Vtq right) => !left.Equals(right);
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Grpc/Protos/scada.proto

@@ -0,0 +1,166 @@
+syntax = "proto3";
+
+option csharp_namespace = "ZB.MOM.WW.LmxProxy.Host.Grpc";
+
+package scada;
+
+// The SCADA service definition
+service ScadaService {
+  // Connection management
+  rpc Connect(ConnectRequest) returns (ConnectResponse);
+  rpc Disconnect(DisconnectRequest) returns (DisconnectResponse);
+  rpc GetConnectionState(GetConnectionStateRequest) returns (GetConnectionStateResponse);
+
+  // Read operations
+  rpc Read(ReadRequest) returns (ReadResponse);
+  rpc ReadBatch(ReadBatchRequest) returns (ReadBatchResponse);
+
+  // Write operations
+  rpc Write(WriteRequest) returns (WriteResponse);
+  rpc WriteBatch(WriteBatchRequest) returns (WriteBatchResponse);
+  rpc WriteBatchAndWait(WriteBatchAndWaitRequest) returns (WriteBatchAndWaitResponse);
+
+  // Subscription operations (server streaming) - now streams VtqMessage directly
+  rpc Subscribe(SubscribeRequest) returns (stream VtqMessage);
+
+  // Authentication
+  rpc CheckApiKey(CheckApiKeyRequest) returns (CheckApiKeyResponse);
+}
+
+// === CONNECTION MESSAGES ===
+
+message ConnectRequest {
+  string client_id = 1;
+  string api_key = 2;
+}
+
+message ConnectResponse {
+  bool success = 1;
+  string message = 2;
+  string session_id = 3;
+}
+
+message DisconnectRequest {
+  string session_id = 1;
+}
+
+message DisconnectResponse {
+  bool success = 1;
+  string message = 2;
+}
+
+message GetConnectionStateRequest {
+  string session_id = 1;
+}
+
+message GetConnectionStateResponse {
+  bool is_connected = 1;
+  string client_id = 2;
+  int64 connected_since_utc_ticks = 3;
+}
+
+// === VTQ MESSAGE ===
+
+message VtqMessage {
+  string tag = 1;
+  string value = 2;
+  int64 timestamp_utc_ticks = 3;
+  string quality = 4;  // "Good", "Uncertain", "Bad"
+}
+
+// === READ MESSAGES ===
+
+message ReadRequest {
+  string session_id = 1;
+  string tag = 2;
+}
+
+message ReadResponse {
+  bool success = 1;
+  string message = 2;
+  VtqMessage vtq = 3;
+}
+
+message ReadBatchRequest {
+  string session_id = 1;
+  repeated string tags = 2;
+}
+
+message ReadBatchResponse {
+  bool success = 1;
+  string message = 2;
+  repeated VtqMessage vtqs = 3;
+}
+
+// === WRITE MESSAGES ===
+
+message WriteRequest {
+  string session_id = 1;
+  string tag = 2;
+  string value = 3;
+}
+
+message WriteResponse {
+  bool success = 1;
+  string message = 2;
+}
+
+message WriteItem {
+  string tag = 1;
+  string value = 2;
+}
+
+message WriteResult {
+  string tag = 1;
+  bool success = 2;
+  string message = 3;
+}
+
+message WriteBatchRequest {
+  string session_id = 1;
+  repeated WriteItem items = 2;
+}
+
+message WriteBatchResponse {
+  bool success = 1;
+  string message = 2;
+  repeated WriteResult results = 3;
+}
+
+message WriteBatchAndWaitRequest {
+  string session_id = 1;
+  repeated WriteItem items = 2;
+  string flag_tag = 3;
+  string flag_value = 4;
+  int32 timeout_ms = 5;
+  int32 poll_interval_ms = 6;
+}
+
+message WriteBatchAndWaitResponse {
+  bool success = 1;
+  string message = 2;
+  repeated WriteResult write_results = 3;
+  bool flag_reached = 4;
+  int32 elapsed_ms = 5;
+}
+
+// === SUBSCRIPTION MESSAGES ===
+
+message SubscribeRequest {
+  string session_id = 1;
+  repeated string tags = 2;
+  int32 sampling_ms = 3;
+}
+
+// Note: Subscribe RPC now streams VtqMessage directly (defined above)
+
+// === AUTHENTICATION MESSAGES ===
+
+message CheckApiKeyRequest {
+  string api_key = 1;
+}
+
+message CheckApiKeyResponse {
+  bool is_valid = 1;
+  string message = 2;
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Program.cs

@@ -0,0 +1,87 @@
+using System;
+using System.IO;
+using Microsoft.Extensions.Configuration;
+using Serilog;
+using Topshelf;
+using ZB.MOM.WW.LmxProxy.Host.Configuration;
+
+namespace ZB.MOM.WW.LmxProxy.Host
+{
+    internal class Program
+    {
+        private static void Main(string[] args)
+        {
+            // Build configuration
+            IConfigurationRoot? configuration = new ConfigurationBuilder()
+                .SetBasePath(Directory.GetCurrentDirectory())
+                .AddJsonFile("appsettings.json", true, true)
+                .AddEnvironmentVariables()
+                .Build();
+
+            // Configure Serilog from appsettings.json
+            Log.Logger = new LoggerConfiguration()
+                .ReadFrom.Configuration(configuration)
+                .CreateLogger();
+
+            try
+            {
+                Log.Information("Starting ZB.MOM.WW.LmxProxy.Host");
+
+                // Load configuration
+                var config = new LmxProxyConfiguration();
+                configuration.Bind(config);
+
+                // Validate configuration
+                if (!ConfigurationValidator.ValidateAndLog(config))
+                {
+                    Log.Fatal("Configuration validation failed. Please check the configuration and try again.");
+                    Environment.ExitCode = 1;
+                    return;
+                }
+
+                // Configure and run the Windows service using TopShelf
+                TopshelfExitCode exitCode = HostFactory.Run(hostConfig =>
+                {
+                    hostConfig.Service<LmxProxyService>(serviceConfig =>
+                    {
+                        serviceConfig.ConstructUsing(() => new LmxProxyService(config));
+                        serviceConfig.WhenStarted(service => service.Start());
+                        serviceConfig.WhenStopped(service => service.Stop());
+                        serviceConfig.WhenPaused(service => service.Pause());
+                        serviceConfig.WhenContinued(service => service.Continue());
+                        serviceConfig.WhenShutdown(service => service.Shutdown());
+                    });
+
+                    hostConfig.UseSerilog(Log.Logger);
+
+                    hostConfig.SetServiceName("ZB.MOM.WW.LmxProxy.Host");
+                    hostConfig.SetDisplayName("SCADA Bridge LMX Proxy");
+                    hostConfig.SetDescription("Provides gRPC access to Archestra MxAccess for SCADA Bridge");
+
+                    hostConfig.StartAutomatically();
+                    hostConfig.EnableServiceRecovery(recoveryConfig =>
+                    {
+                        recoveryConfig.RestartService(config.ServiceRecovery.FirstFailureDelayMinutes);
+                        recoveryConfig.RestartService(config.ServiceRecovery.SecondFailureDelayMinutes);
+                        recoveryConfig.RestartService(config.ServiceRecovery.SubsequentFailureDelayMinutes);
+                        recoveryConfig.SetResetPeriod(config.ServiceRecovery.ResetPeriodDays);
+                    });
+
+                    hostConfig.OnException(ex => { Log.Fatal(ex, "Unhandled exception in service"); });
+                });
+
+                Log.Information("Service exited with code: {ExitCode}", exitCode);
+                Environment.ExitCode = (int)exitCode;
+            }
+            catch (Exception ex)
+            {
+                Log.Fatal(ex, "Failed to start service");
+                Environment.ExitCode = 1;
+            }
+            finally
+            {
+                Log.CloseAndFlush();
+            }
+        }
+    }
+}

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/ZB.MOM.WW.LmxProxy.Host.csproj

@@ -0,0 +1,65 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net48</TargetFramework>
+    <OutputType>Exe</OutputType>
+    <LangVersion>9.0</LangVersion>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+    <RootNamespace>ZB.MOM.WW.LmxProxy.Host</RootNamespace>
+    <AssemblyName>ZB.MOM.WW.LmxProxy.Host</AssemblyName>
+    <!-- Force x86 architecture for all configurations (required by ArchestrA.MXAccess) -->
+    <PlatformTarget>x86</PlatformTarget>
+    <Platforms>x86</Platforms>
+    <Prefer32Bit>true</Prefer32Bit>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Grpc.Core" Version="2.46.6"/>
+    <PackageReference Include="Grpc.Tools" Version="2.51.0">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="Google.Protobuf" Version="3.21.12"/>
+    <PackageReference Include="Topshelf" Version="4.3.0"/>
+    <PackageReference Include="Topshelf.Serilog" Version="4.3.0"/>
+    <PackageReference Include="Serilog" Version="2.10.0"/>
+    <PackageReference Include="Serilog.Sinks.Console" Version="4.0.1"/>
+    <PackageReference Include="Serilog.Sinks.File" Version="5.0.0"/>
+    <PackageReference Include="Serilog.Settings.Configuration" Version="3.3.0"/>
+    <PackageReference Include="Serilog.Formatting.Compact" Version="1.1.0"/>
+    <PackageReference Include="System.Threading.Channels" Version="4.7.1"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.32"/>
+    <PackageReference Include="Polly" Version="7.2.4"/>
+    <PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks" Version="3.1.32"/>
+    <PackageReference Include="System.Memory" Version="4.5.5"/>
+    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.7.1"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Reference Include="ArchestrA.MXAccess">
+      <HintPath>..\..\lib\ArchestrA.MXAccess.dll</HintPath>
+      <Private>true</Private>
+    </Reference>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Protobuf Include="Grpc\Protos\*.proto" GrpcServices="Both"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Update="appsettings.json">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Update="appsettings.*.json">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Update="App.config">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+  </ItemGroup>
+
+</Project>

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/appsettings.json

@@ -0,0 +1,84 @@
+{
+  "GrpcPort": 50051,
+  "ApiKeyConfigFile": "apikeys.json",
+  "Subscription": {
+    "ChannelCapacity": 1000,
+    "ChannelFullMode": "DropOldest"
+  },
+  "ServiceRecovery": {
+    "FirstFailureDelayMinutes": 1,
+    "SecondFailureDelayMinutes": 5,
+    "SubsequentFailureDelayMinutes": 10,
+    "ResetPeriodDays": 1
+  },
+  "Connection": {
+    "MonitorIntervalSeconds": 5,
+    "ConnectionTimeoutSeconds": 30,
+    "AutoReconnect": true,
+    "ReadTimeoutSeconds": 5,
+    "WriteTimeoutSeconds": 5,
+    "MaxConcurrentOperations": 10
+  },
+  "PerformanceMetrics": {
+    "ReportingIntervalSeconds": 60,
+    "Enabled": true,
+    "MaxSamplesPerMetric": 1000
+  },
+  "HealthCheck": {
+    "Enabled": true,
+    "TestTagAddress": "TestChannel.TestDevice.TestTag",
+    "MaxStaleDataMinutes": 5
+  },
+  "RetryPolicies": {
+    "ReadRetryCount": 3,
+    "WriteRetryCount": 3,
+    "ConnectionRetryCount": 5,
+    "CircuitBreakerThreshold": 5,
+    "CircuitBreakerDurationSeconds": 30
+  },
+  "Tls": {
+    "Enabled": true,
+    "ServerCertificatePath": "certs/server.crt",
+    "ServerKeyPath": "certs/server.key",
+    "ClientCaCertificatePath": "certs/ca.crt",
+    "RequireClientCertificate": false,
+    "CheckCertificateRevocation": false
+  },
+  "WebServer": {
+    "Enabled": true,
+    "Port": 8080
+  },
+  "Serilog": {
+    "MinimumLevel": {
+      "Default": "Information",
+      "Override": {
+        "Microsoft": "Warning",
+        "System": "Warning",
+        "Grpc": "Information"
+      }
+    },
+    "WriteTo": [
+      {
+        "Name": "Console",
+        "Args": {
+          "theme": "Serilog.Sinks.SystemConsole.Themes.AnsiConsoleTheme::Code, Serilog.Sinks.Console",
+          "outputTemplate": "[{Timestamp:HH:mm:ss} {Level:u3}] {Message:lj} {Properties:j}{NewLine}{Exception}"
+        }
+      },
+      {
+        "Name": "File",
+        "Args": {
+          "path": "logs/lmxproxy-.txt",
+          "rollingInterval": "Day",
+          "retainedFileCountLimit": 30,
+          "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] {SourceContext} {Message:lj}{NewLine}{Exception}"
+        }
+      }
+    ],
+    "Enrich": [
+      "FromLogContext",
+      "WithMachineName",
+      "WithThreadId"
+    ]
+  }
+}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/Domain/ConnectionState.cs

@@ -1,49 +1,12 @@
-using System;
-
 namespace ZB.MOM.WW.LmxProxy.Client.Domain;
 
-/// <summary>
+/// <summary>Represents the state of a connection to the LmxProxy service.</summary>
-/// Represents the connection state of an LmxProxy client.
-/// </summary>
 public enum ConnectionState
 {
-	/// <summary>Not connected to the server.</summary>
     Disconnected,
-
-	/// <summary>Connection attempt in progress.</summary>
     Connecting,
-
-	/// <summary>Connected and ready for operations.</summary>
     Connected,
-
-	/// <summary>Graceful disconnect in progress.</summary>
     Disconnecting,
-
-	/// <summary>Connection failed with an error.</summary>
     Error,
-
-	/// <summary>Attempting to re-establish a lost connection.</summary>
     Reconnecting
 }
-
-/// <summary>
-/// Event arguments for connection state change notifications.
-/// </summary>
-public class ConnectionStateChangedEventArgs : EventArgs
-{
-	/// <summary>The previous connection state.</summary>
-	public ConnectionState OldState { get; }
-
-	/// <summary>The new connection state.</summary>
-	public ConnectionState NewState { get; }
-
-	/// <summary>Optional message describing the state change (e.g., error details).</summary>
-	public string? Message { get; }
-
-	public ConnectionStateChangedEventArgs(ConnectionState oldState, ConnectionState newState, string? message = null)
-	{
-		OldState = oldState;
-		NewState = newState;
-		Message = message;
-	}
-}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/Domain/Quality.cs

@@ -2,117 +2,50 @@ namespace ZB.MOM.WW.LmxProxy.Client.Domain;
 
 /// <summary>
 /// OPC-style quality codes for SCADA data values.
-/// Based on OPC DA quality encoding as a single byte:
+/// Byte value matches OPC DA quality low byte for direct round-trip.
-/// bits 7–6 = major (00=Bad, 01=Uncertain, 11=Good),
-/// bits 5–2 = substatus, bits 1–0 = limit (00=None, 01=Low, 10=High, 11=Constant).
 /// </summary>
 public enum Quality : byte
 {
-	/// <summary>Bad – non-specific.</summary>
+    // ─────────────── Bad family (0-31) ───────────────
     Bad = 0,
-
-	/// <summary>Bad – configuration error in the server.</summary>
     Bad_ConfigError = 4,
-
-	/// <summary>Bad – input source is not connected.</summary>
     Bad_NotConnected = 8,
-
-	/// <summary>Bad – device failure detected.</summary>
     Bad_DeviceFailure = 12,
-
-	/// <summary>Bad – sensor failure detected.</summary>
     Bad_SensorFailure = 16,
-
-	/// <summary>Bad – last known value (communication lost, value stale).</summary>
     Bad_LastKnownValue = 20,
-
-	/// <summary>Bad – communication failure.</summary>
     Bad_CommFailure = 24,
-
-	/// <summary>Bad – item is out of service.</summary>
     Bad_OutOfService = 28,
+    Bad_WaitingForInitialData = 32,
 
-	/// <summary>Uncertain – non-specific.</summary>
+    // ──────────── Uncertain family (64-95) ───────────
     Uncertain = 64,
-
-	/// <summary>Uncertain – non-specific, low limited.</summary>
     Uncertain_LowLimited = 65,
-
-	/// <summary>Uncertain – non-specific, high limited.</summary>
     Uncertain_HighLimited = 66,
-
-	/// <summary>Uncertain – non-specific, constant.</summary>
     Uncertain_Constant = 67,
-
-	/// <summary>Uncertain – last usable value.</summary>
     Uncertain_LastUsable = 68,
-
-	/// <summary>Uncertain – last usable value, low limited.</summary>
     Uncertain_LastUsable_LL = 69,
-
-	/// <summary>Uncertain – last usable value, high limited.</summary>
     Uncertain_LastUsable_HL = 70,
-
-	/// <summary>Uncertain – last usable value, constant.</summary>
     Uncertain_LastUsable_Cnst = 71,
-
-	/// <summary>Uncertain – sensor not accurate.</summary>
     Uncertain_SensorNotAcc = 80,
-
-	/// <summary>Uncertain – sensor not accurate, low limited.</summary>
     Uncertain_SensorNotAcc_LL = 81,
-
-	/// <summary>Uncertain – sensor not accurate, high limited.</summary>
     Uncertain_SensorNotAcc_HL = 82,
-
-	/// <summary>Uncertain – sensor not accurate, constant.</summary>
     Uncertain_SensorNotAcc_C = 83,
-
-	/// <summary>Uncertain – engineering units exceeded.</summary>
     Uncertain_EuExceeded = 84,
-
-	/// <summary>Uncertain – engineering units exceeded, low limited.</summary>
     Uncertain_EuExceeded_LL = 85,
-
-	/// <summary>Uncertain – engineering units exceeded, high limited.</summary>
     Uncertain_EuExceeded_HL = 86,
-
-	/// <summary>Uncertain – engineering units exceeded, constant.</summary>
     Uncertain_EuExceeded_C = 87,
-
-	/// <summary>Uncertain – sub-normal operating conditions.</summary>
     Uncertain_SubNormal = 88,
-
-	/// <summary>Uncertain – sub-normal, low limited.</summary>
     Uncertain_SubNormal_LL = 89,
-
-	/// <summary>Uncertain – sub-normal, high limited.</summary>
     Uncertain_SubNormal_HL = 90,
-
-	/// <summary>Uncertain – sub-normal, constant.</summary>
     Uncertain_SubNormal_C = 91,
 
-	/// <summary>Good – non-specific.</summary>
+    // ─────────────── Good family (192-219) ────────────
     Good = 192,
-
-	/// <summary>Good – low limited.</summary>
     Good_LowLimited = 193,
-
-	/// <summary>Good – high limited.</summary>
     Good_HighLimited = 194,
-
-	/// <summary>Good – constant.</summary>
     Good_Constant = 195,
-
-	/// <summary>Good – local override active.</summary>
     Good_LocalOverride = 216,
-
-	/// <summary>Good – local override active, low limited.</summary>
     Good_LocalOverride_LL = 217,
-
-	/// <summary>Good – local override active, high limited.</summary>
     Good_LocalOverride_HL = 218,
-
-	/// <summary>Good – local override active, constant.</summary>
     Good_LocalOverride_C = 219
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/Domain/QualityExtensions.cs

@@ -1,8 +1,14 @@
 namespace ZB.MOM.WW.LmxProxy.Client.Domain;
 
+/// <summary>Extension methods for <see cref="Quality"/>.</summary>
 public static class QualityExtensions
 {
-	public static bool IsGood(this Quality q) => (byte)q >= 128;
+    /// <summary>Returns true if quality is in the Good family (byte >= 192).</summary>
+    public static bool IsGood(this Quality q) => (byte)q >= 192;
+
+    /// <summary>Returns true if quality is in the Uncertain family (byte 64-127).</summary>
     public static bool IsUncertain(this Quality q) => (byte)q is >= 64 and < 128;
+
+    /// <summary>Returns true if quality is in the Bad family (byte < 64).</summary>
     public static bool IsBad(this Quality q) => (byte)q < 64;
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/Domain/ScadaContracts.cs

@@ -10,101 +10,230 @@ namespace ZB.MOM.WW.LmxProxy.Client.Domain;
 // Service contract
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>
-/// Code-first gRPC service contract for SCADA operations.
-/// </summary>
 [ServiceContract(Name = "scada.ScadaService")]
 public interface IScadaService
 {
-	/// <summary>Establishes a connection with the SCADA service.</summary>
     ValueTask<ConnectResponse> ConnectAsync(ConnectRequest request);
-
-	/// <summary>Terminates a SCADA service connection.</summary>
     ValueTask<DisconnectResponse> DisconnectAsync(DisconnectRequest request);
-
-	/// <summary>Retrieves the current state of a SCADA connection.</summary>
     ValueTask<GetConnectionStateResponse> GetConnectionStateAsync(GetConnectionStateRequest request);
-
-	/// <summary>Reads a single tag value from the SCADA system.</summary>
     ValueTask<ReadResponse> ReadAsync(ReadRequest request);
-
-	/// <summary>Reads multiple tag values from the SCADA system in a batch operation.</summary>
     ValueTask<ReadBatchResponse> ReadBatchAsync(ReadBatchRequest request);
-
-	/// <summary>Writes a single value to a tag in the SCADA system.</summary>
     ValueTask<WriteResponse> WriteAsync(WriteRequest request);
-
-	/// <summary>Writes multiple values to tags in the SCADA system in a batch operation.</summary>
     ValueTask<WriteBatchResponse> WriteBatchAsync(WriteBatchRequest request);
-
-	/// <summary>Writes multiple values and waits for a completion flag before returning.</summary>
     ValueTask<WriteBatchAndWaitResponse> WriteBatchAndWaitAsync(WriteBatchAndWaitRequest request);
-
-	/// <summary>Subscribes to real-time value changes from specified tags.</summary>
     IAsyncEnumerable<VtqMessage> SubscribeAsync(SubscribeRequest request, CancellationToken cancellationToken = default);
-
-	/// <summary>Validates an API key for authentication.</summary>
     ValueTask<CheckApiKeyResponse> CheckApiKeyAsync(CheckApiKeyRequest request);
 }
 
 // ────────────────────────────────────────────────────────────────
-// VTQ message
+// Typed Value System (v2)
 // ────────────────────────────────────────────────────────────────
 
 /// <summary>
-/// Value-Timestamp-Quality message transmitted over gRPC.
+/// Carries a value in its native type via a protobuf oneof.
-/// All values are string-encoded; timestamps are UTC ticks.
+/// Exactly one property will be non-default. All-default = null value.
+/// protobuf-net uses the first non-default field in field-number order for oneof.
 /// </summary>
+[DataContract]
+public class TypedValue
+{
+    [DataMember(Order = 1)]
+    public bool BoolValue { get; set; }
+
+    [DataMember(Order = 2)]
+    public int Int32Value { get; set; }
+
+    [DataMember(Order = 3)]
+    public long Int64Value { get; set; }
+
+    [DataMember(Order = 4)]
+    public float FloatValue { get; set; }
+
+    [DataMember(Order = 5)]
+    public double DoubleValue { get; set; }
+
+    [DataMember(Order = 6)]
+    public string? StringValue { get; set; }
+
+    [DataMember(Order = 7)]
+    public byte[]? BytesValue { get; set; }
+
+    [DataMember(Order = 8)]
+    public long DatetimeValue { get; set; }
+
+    [DataMember(Order = 9)]
+    public ArrayValue? ArrayValue { get; set; }
+
+    /// <summary>
+    /// Indicates which oneof case is set. Determined by checking non-default values.
+    /// This is NOT a wire field -- it's a convenience helper.
+    /// </summary>
+    public TypedValueCase GetValueCase()
+    {
+        // Check in reverse priority order to handle protobuf oneof semantics.
+        // For the oneof, only one should be set at a time.
+        if (ArrayValue != null) return TypedValueCase.ArrayValue;
+        if (DatetimeValue != 0) return TypedValueCase.DatetimeValue;
+        if (BytesValue != null) return TypedValueCase.BytesValue;
+        if (StringValue != null) return TypedValueCase.StringValue;
+        if (DoubleValue != 0d) return TypedValueCase.DoubleValue;
+        if (FloatValue != 0f) return TypedValueCase.FloatValue;
+        if (Int64Value != 0) return TypedValueCase.Int64Value;
+        if (Int32Value != 0) return TypedValueCase.Int32Value;
+        if (BoolValue) return TypedValueCase.BoolValue;
+        return TypedValueCase.None;
+    }
+}
+
+/// <summary>Identifies which field in TypedValue is set.</summary>
+public enum TypedValueCase
+{
+    None = 0,
+    BoolValue = 1,
+    Int32Value = 2,
+    Int64Value = 3,
+    FloatValue = 4,
+    DoubleValue = 5,
+    StringValue = 6,
+    BytesValue = 7,
+    DatetimeValue = 8,
+    ArrayValue = 9
+}
+
+/// <summary>Container for typed arrays. Exactly one field will be set.</summary>
+[DataContract]
+public class ArrayValue
+{
+    [DataMember(Order = 1)]
+    public BoolArray? BoolValues { get; set; }
+
+    [DataMember(Order = 2)]
+    public Int32Array? Int32Values { get; set; }
+
+    [DataMember(Order = 3)]
+    public Int64Array? Int64Values { get; set; }
+
+    [DataMember(Order = 4)]
+    public FloatArray? FloatValues { get; set; }
+
+    [DataMember(Order = 5)]
+    public DoubleArray? DoubleValues { get; set; }
+
+    [DataMember(Order = 6)]
+    public StringArray? StringValues { get; set; }
+}
+
+[DataContract]
+public class BoolArray
+{
+    [DataMember(Order = 1)]
+    public List<bool> Values { get; set; } = [];
+}
+
+[DataContract]
+public class Int32Array
+{
+    [DataMember(Order = 1)]
+    public List<int> Values { get; set; } = [];
+}
+
+[DataContract]
+public class Int64Array
+{
+    [DataMember(Order = 1)]
+    public List<long> Values { get; set; } = [];
+}
+
+[DataContract]
+public class FloatArray
+{
+    [DataMember(Order = 1)]
+    public List<float> Values { get; set; } = [];
+}
+
+[DataContract]
+public class DoubleArray
+{
+    [DataMember(Order = 1)]
+    public List<double> Values { get; set; } = [];
+}
+
+[DataContract]
+public class StringArray
+{
+    [DataMember(Order = 1)]
+    public List<string> Values { get; set; } = [];
+}
+
+// ────────────────────────────────────────────────────────────────
+// Quality Code (v2)
+// ────────────────────────────────────────────────────────────────
+
+/// <summary>
+/// OPC UA-style quality code with numeric status code and symbolic name.
+/// </summary>
+[DataContract]
+public class QualityCode
+{
+    [DataMember(Order = 1)]
+    public uint StatusCode { get; set; }
+
+    [DataMember(Order = 2)]
+    public string SymbolicName { get; set; } = string.Empty;
+
+    /// <summary>Returns true if quality category is Good (high bits 0x00).</summary>
+    public bool IsGood => (StatusCode & 0xC0000000) == 0x00000000;
+
+    /// <summary>Returns true if quality category is Uncertain (high bits 0x40).</summary>
+    public bool IsUncertain => (StatusCode & 0xC0000000) == 0x40000000;
+
+    /// <summary>Returns true if quality category is Bad (high bits 0x80).</summary>
+    public bool IsBad => (StatusCode & 0xC0000000) == 0x80000000;
+}
+
+// ────────────────────────────────────────────────────────────────
+// VTQ message (v2)
+// ────────────────────────────────────────────────────────────────
+
 [DataContract]
 public class VtqMessage
 {
-	/// <summary>Tag address.</summary>
     [DataMember(Order = 1)]
     public string Tag { get; set; } = string.Empty;
 
-	/// <summary>Value encoded as a string.</summary>
     [DataMember(Order = 2)]
-	public string Value { get; set; } = string.Empty;
+    public TypedValue? Value { get; set; }
 
-	/// <summary>UTC timestamp as DateTime.Ticks (100ns intervals since 0001-01-01).</summary>
     [DataMember(Order = 3)]
     public long TimestampUtcTicks { get; set; }
 
-	/// <summary>Quality string: "Good", "Uncertain", or "Bad".</summary>
     [DataMember(Order = 4)]
-	public string Quality { get; set; } = string.Empty;
+    public QualityCode? Quality { get; set; }
 }
 
 // ────────────────────────────────────────────────────────────────
 // Connect
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to establish a session with the proxy server.</summary>
 [DataContract]
 public class ConnectRequest
 {
-	/// <summary>Client identifier (e.g., "ScadaLink-{guid}").</summary>
     [DataMember(Order = 1)]
     public string ClientId { get; set; } = string.Empty;
 
-	/// <summary>API key for authentication (empty if none required).</summary>
     [DataMember(Order = 2)]
     public string ApiKey { get; set; } = string.Empty;
 }
 
-/// <summary>Response from a Connect call.</summary>
 [DataContract]
 public class ConnectResponse
 {
-	/// <summary>Whether the connection was established successfully.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Status or error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 
-	/// <summary>Session ID (32-char hex GUID). Only valid when <see cref="Success"/> is <c>true</c>.</summary>
     [DataMember(Order = 3)]
     public string SessionId { get; set; } = string.Empty;
 }
@@ -113,24 +242,19 @@ public class ConnectResponse
 // Disconnect
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to terminate a session.</summary>
 [DataContract]
 public class DisconnectRequest
 {
-	/// <summary>Active session ID to disconnect.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 }
 
-/// <summary>Response from a Disconnect call.</summary>
 [DataContract]
 public class DisconnectResponse
 {
-	/// <summary>Whether the disconnect succeeded.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Status or error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 }
@@ -139,28 +263,22 @@ public class DisconnectResponse
 // GetConnectionState
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to query connection state for a session.</summary>
 [DataContract]
 public class GetConnectionStateRequest
 {
-	/// <summary>Session ID to query.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 }
 
-/// <summary>Response with connection state information.</summary>
 [DataContract]
 public class GetConnectionStateResponse
 {
-	/// <summary>Whether the session is currently connected.</summary>
     [DataMember(Order = 1)]
     public bool IsConnected { get; set; }
 
-	/// <summary>Client identifier for this session.</summary>
     [DataMember(Order = 2)]
     public string ClientId { get; set; } = string.Empty;
 
-	/// <summary>UTC ticks when the connection was established.</summary>
     [DataMember(Order = 3)]
     public long ConnectedSinceUtcTicks { get; set; }
 }
@@ -169,66 +287,48 @@ public class GetConnectionStateResponse
 // Read
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to read a single tag.</summary>
 [DataContract]
 public class ReadRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag address to read.</summary>
     [DataMember(Order = 2)]
     public string Tag { get; set; } = string.Empty;
 }
 
-/// <summary>Response from a single-tag Read call.</summary>
 [DataContract]
 public class ReadResponse
 {
-	/// <summary>Whether the read succeeded.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Error message if the read failed.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 
-	/// <summary>The value-timestamp-quality result.</summary>
     [DataMember(Order = 3)]
     public VtqMessage? Vtq { get; set; }
 }
 
-// ────────────────────────────────────────────────────────────────
-// ReadBatch
-// ────────────────────────────────────────────────────────────────
-
-/// <summary>Request to read multiple tags in a single round-trip.</summary>
 [DataContract]
 public class ReadBatchRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag addresses to read.</summary>
     [DataMember(Order = 2)]
     public List<string> Tags { get; set; } = [];
 }
 
-/// <summary>Response from a batch Read call.</summary>
 [DataContract]
 public class ReadBatchResponse
 {
-	/// <summary>False if any tag read failed.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 
-	/// <summary>VTQ results in the same order as the request tags.</summary>
     [DataMember(Order = 3)]
     public List<VtqMessage> Vtqs { get; set; } = [];
 }
@@ -237,100 +337,71 @@ public class ReadBatchResponse
 // Write
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to write a single tag value.</summary>
 [DataContract]
 public class WriteRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag address to write.</summary>
     [DataMember(Order = 2)]
     public string Tag { get; set; } = string.Empty;
 
-	/// <summary>Value as a string (parsed server-side).</summary>
     [DataMember(Order = 3)]
-	public string Value { get; set; } = string.Empty;
+    public TypedValue? Value { get; set; }
 }
 
-/// <summary>Response from a single-tag Write call.</summary>
 [DataContract]
 public class WriteResponse
 {
-	/// <summary>Whether the write succeeded.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Status or error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 }
 
-// ────────────────────────────────────────────────────────────────
-// WriteItem / WriteResult
-// ────────────────────────────────────────────────────────────────
-
-/// <summary>A single tag-value pair for batch write operations.</summary>
 [DataContract]
 public class WriteItem
 {
-	/// <summary>Tag address.</summary>
     [DataMember(Order = 1)]
     public string Tag { get; set; } = string.Empty;
 
-	/// <summary>Value as a string.</summary>
     [DataMember(Order = 2)]
-	public string Value { get; set; } = string.Empty;
+    public TypedValue? Value { get; set; }
 }
 
-/// <summary>Per-item result from a batch write operation.</summary>
 [DataContract]
 public class WriteResult
 {
-	/// <summary>Tag address that was written.</summary>
     [DataMember(Order = 1)]
     public string Tag { get; set; } = string.Empty;
 
-	/// <summary>Whether the individual write succeeded.</summary>
     [DataMember(Order = 2)]
     public bool Success { get; set; }
 
-	/// <summary>Error message for this item, if any.</summary>
     [DataMember(Order = 3)]
     public string Message { get; set; } = string.Empty;
 }
 
-// ────────────────────────────────────────────────────────────────
-// WriteBatch
-// ────────────────────────────────────────────────────────────────
-
-/// <summary>Request to write multiple tag values in a single round-trip.</summary>
 [DataContract]
 public class WriteBatchRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag-value pairs to write.</summary>
     [DataMember(Order = 2)]
     public List<WriteItem> Items { get; set; } = [];
 }
 
-/// <summary>Response from a batch Write call.</summary>
 [DataContract]
 public class WriteBatchResponse
 {
-	/// <summary>Overall success — false if any item failed.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Status or error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 
-	/// <summary>Per-item write results.</summary>
     [DataMember(Order = 3)]
     public List<WriteResult> Results { get; set; } = [];
 }
@@ -339,59 +410,43 @@ public class WriteBatchResponse
 // WriteBatchAndWait
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>
-/// Request to write multiple tag values then poll a flag tag
-/// until it matches an expected value or the timeout expires.
-/// </summary>
 [DataContract]
 public class WriteBatchAndWaitRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag-value pairs to write.</summary>
     [DataMember(Order = 2)]
     public List<WriteItem> Items { get; set; } = [];
 
-	/// <summary>Tag to poll after writes complete.</summary>
     [DataMember(Order = 3)]
     public string FlagTag { get; set; } = string.Empty;
 
-	/// <summary>Expected value for the flag tag (string comparison).</summary>
     [DataMember(Order = 4)]
-	public string FlagValue { get; set; } = string.Empty;
+    public TypedValue? FlagValue { get; set; }
 
-	/// <summary>Timeout in milliseconds (default 5000 if &lt;= 0).</summary>
     [DataMember(Order = 5)]
     public int TimeoutMs { get; set; }
 
-	/// <summary>Poll interval in milliseconds (default 100 if &lt;= 0).</summary>
     [DataMember(Order = 6)]
     public int PollIntervalMs { get; set; }
 }
 
-/// <summary>Response from a WriteBatchAndWait call.</summary>
 [DataContract]
 public class WriteBatchAndWaitResponse
 {
-	/// <summary>Overall operation success.</summary>
     [DataMember(Order = 1)]
     public bool Success { get; set; }
 
-	/// <summary>Status or error message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 
-	/// <summary>Per-item write results.</summary>
     [DataMember(Order = 3)]
     public List<WriteResult> WriteResults { get; set; } = [];
 
-	/// <summary>Whether the flag tag matched the expected value before timeout.</summary>
     [DataMember(Order = 4)]
     public bool FlagReached { get; set; }
 
-	/// <summary>Total elapsed time in milliseconds.</summary>
     [DataMember(Order = 5)]
     public int ElapsedMs { get; set; }
 }
@@ -400,19 +455,15 @@ public class WriteBatchAndWaitResponse
 // Subscribe
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to subscribe to value change notifications on one or more tags.</summary>
 [DataContract]
 public class SubscribeRequest
 {
-	/// <summary>Valid session ID.</summary>
     [DataMember(Order = 1)]
     public string SessionId { get; set; } = string.Empty;
 
-	/// <summary>Tag addresses to monitor.</summary>
     [DataMember(Order = 2)]
     public List<string> Tags { get; set; } = [];
 
-	/// <summary>Backend sampling interval in milliseconds.</summary>
     [DataMember(Order = 3)]
     public int SamplingMs { get; set; }
 }
@@ -421,24 +472,19 @@ public class SubscribeRequest
 // CheckApiKey
 // ────────────────────────────────────────────────────────────────
 
-/// <summary>Request to validate an API key without creating a session.</summary>
 [DataContract]
 public class CheckApiKeyRequest
 {
-	/// <summary>API key to validate.</summary>
     [DataMember(Order = 1)]
     public string ApiKey { get; set; } = string.Empty;
 }
 
-/// <summary>Response from an API key validation check.</summary>
 [DataContract]
 public class CheckApiKeyResponse
 {
-	/// <summary>Whether the API key is valid.</summary>
     [DataMember(Order = 1)]
     public bool IsValid { get; set; }
 
-	/// <summary>Validation message.</summary>
     [DataMember(Order = 2)]
     public string Message { get; set; } = string.Empty;
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/Domain/Vtq.cs

@@ -1,27 +1,12 @@
-using System;
-
 namespace ZB.MOM.WW.LmxProxy.Client.Domain;
 
-/// <summary>
+/// <summary>Value, Timestamp, and Quality for SCADA data.</summary>
-/// Value, Timestamp, and Quality structure for SCADA data.
-/// </summary>
-/// <param name="Value">The value.</param>
-/// <param name="Timestamp">The timestamp when the value was read.</param>
-/// <param name="Quality">The quality of the value.</param>
 public readonly record struct Vtq(object? Value, DateTime Timestamp, Quality Quality)
 {
-	/// <summary>Creates a new VTQ with the specified value and quality, using the current UTC timestamp.</summary>
+    public static Vtq Good(object value) => new(value, DateTime.UtcNow, Quality.Good);
-	public static Vtq New(object? value, Quality quality) => new(value, DateTime.UtcNow, quality);
-
-	/// <summary>Creates a new VTQ with the specified value, timestamp, and quality.</summary>
-	public static Vtq New(object? value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
-
-	/// <summary>Creates a Good-quality VTQ with the current UTC time.</summary>
-	public static Vtq Good(object? value) => new(value, DateTime.UtcNow, Quality.Good);
-
-	/// <summary>Creates a Bad-quality VTQ with the current UTC time.</summary>
     public static Vtq Bad(object? value = null) => new(value, DateTime.UtcNow, Quality.Bad);
+    public static Vtq Uncertain(object value) => new(value, DateTime.UtcNow, Quality.Uncertain);
 
-	/// <summary>Creates an Uncertain-quality VTQ with the current UTC time.</summary>
+    public override string ToString() =>
-	public static Vtq Uncertain(object? value) => new(value, DateTime.UtcNow, Quality.Uncertain);
+        $"{{Value={Value}, Timestamp={Timestamp:yyyy-MM-dd HH:mm:ss.fff}, Quality={Quality}}}";
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Client/ZB.MOM.WW.LmxProxy.Client.csproj

@@ -4,11 +4,12 @@
     <TargetFramework>net10.0</TargetFramework>
     <LangVersion>latest</LangVersion>
     <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
     <RootNamespace>ZB.MOM.WW.LmxProxy.Client</RootNamespace>
     <AssemblyName>ZB.MOM.WW.LmxProxy.Client</AssemblyName>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <IsPackable>true</IsPackable>
-    <Description>gRPC client library for LmxProxy service</Description>
+    <Description>gRPC client library for LmxProxy SCADA proxy service</Description>
     <PlatformTarget>AnyCPU</PlatformTarget>
     <Platforms>AnyCPU</Platforms>
   </PropertyGroup>

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/ConnectionState.cs

@@ -5,34 +5,11 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
     /// </summary>
     public enum ConnectionState
     {
-        /// <summary>
-        ///     The client is disconnected.
-        /// </summary>
         Disconnected,
-
-        /// <summary>
-        ///     The client is in the process of connecting.
-        /// </summary>
         Connecting,
-
-        /// <summary>
-        ///     The client is connected.
-        /// </summary>
         Connected,
-
-        /// <summary>
-        ///     The client is in the process of disconnecting.
-        /// </summary>
         Disconnecting,
-
-        /// <summary>
-        ///     The client encountered an error.
-        /// </summary>
         Error,
-
-        /// <summary>
-        ///     The client is reconnecting after a connection loss.
-        /// </summary>
         Reconnecting
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/ConnectionStateChangedEventArgs.cs

@@ -7,12 +7,6 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
     /// </summary>
     public class ConnectionStateChangedEventArgs : EventArgs
     {
-        /// <summary>
-        ///     Initializes a new instance of the <see cref="ConnectionStateChangedEventArgs" /> class.
-        /// </summary>
-        /// <param name="previousState">The previous connection state.</param>
-        /// <param name="currentState">The current connection state.</param>
-        /// <param name="message">Optional message providing additional information about the state change.</param>
         public ConnectionStateChangedEventArgs(ConnectionState previousState, ConnectionState currentState,
             string? message = null)
         {
@@ -22,24 +16,9 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
             Message = message;
         }
 
-        /// <summary>
-        ///     Gets the previous connection state.
-        /// </summary>
         public ConnectionState PreviousState { get; }
-
-        /// <summary>
-        ///     Gets the current connection state.
-        /// </summary>
         public ConnectionState CurrentState { get; }
-
-        /// <summary>
-        ///     Gets the timestamp when the state change occurred.
-        /// </summary>
         public DateTime Timestamp { get; }
-
-        /// <summary>
-        ///     Gets additional information about the state change, such as error messages.
-        /// </summary>
         public string? Message { get; }
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/IScadaClient.cs

@@ -6,99 +6,62 @@ using System.Threading.Tasks;
 namespace ZB.MOM.WW.LmxProxy.Host.Domain
 {
     /// <summary>
-    ///     Interface for SCADA system clients.
+    ///     Interface for SCADA system clients (MxAccess wrapper).
     /// </summary>
     public interface IScadaClient : IAsyncDisposable
     {
-        /// <summary>
+        /// <summary>Gets whether the client is connected to MxAccess.</summary>
-        ///     Gets the connection status.
-        /// </summary>
         bool IsConnected { get; }
 
-        /// <summary>
+        /// <summary>Gets the current connection state.</summary>
-        ///     Gets the current connection state.
-        /// </summary>
         ConnectionState ConnectionState { get; }
 
-        /// <summary>
+        /// <summary>Occurs when the connection state changes.</summary>
-        ///     Occurs when the connection state changes.
-        /// </summary>
         event EventHandler<ConnectionStateChangedEventArgs> ConnectionStateChanged;
 
-        /// <summary>
+        /// <summary>Connects to MxAccess.</summary>
-        ///     Connects to the SCADA system.
-        /// </summary>
-        /// <param name="ct">Cancellation token.</param>
         Task ConnectAsync(CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Disconnects from MxAccess.</summary>
-        ///     Disconnects from the SCADA system.
-        /// </summary>
-        /// <param name="ct">Cancellation token.</param>
         Task DisconnectAsync(CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Reads a single tag value.</summary>
-        ///     Reads a single tag value from the SCADA system.
+        /// <returns>VTQ with typed value.</returns>
-        /// </summary>
-        /// <param name="address">The tag address.</param>
-        /// <param name="ct">Cancellation token.</param>
-        /// <returns>The value, timestamp, and quality.</returns>
         Task<Vtq> ReadAsync(string address, CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Reads multiple tag values with semaphore-controlled concurrency.</summary>
-        ///     Reads multiple tag values from the SCADA system.
+        /// <returns>Dictionary of address to VTQ.</returns>
-        /// </summary>
+        Task<IReadOnlyDictionary<string, Vtq>> ReadBatchAsync(IEnumerable<string> addresses, CancellationToken ct = default);
-        /// <param name="addresses">The tag addresses.</param>
-        /// <param name="ct">Cancellation token.</param>
-        /// <returns>Dictionary of address to VTQ values.</returns>
-        Task<IReadOnlyDictionary<string, Vtq>>
-            ReadBatchAsync(IEnumerable<string> addresses, CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Writes a single tag value. Value is a native .NET type (not string).</summary>
-        ///     Writes a single tag value to the SCADA system.
-        /// </summary>
-        /// <param name="address">The tag address.</param>
-        /// <param name="value">The value to write.</param>
-        /// <param name="ct">Cancellation token.</param>
         Task WriteAsync(string address, object value, CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Writes multiple tag values with semaphore-controlled concurrency.</summary>
-        ///     Writes multiple tag values to the SCADA system.
-        /// </summary>
-        /// <param name="values">Dictionary of address to value.</param>
-        /// <param name="ct">Cancellation token.</param>
         Task WriteBatchAsync(IReadOnlyDictionary<string, object> values, CancellationToken ct = default);
 
         /// <summary>
-        ///     Writes a batch of tag values and a flag tag, then waits for a response tag to
+        ///     Writes a batch of values, then polls flagTag until it equals flagValue or timeout expires.
-        ///     equal the expected value.
+        ///     Returns (writeSuccess, flagReached, elapsedMs).
         /// </summary>
-        /// <param name="values">The regular tag values to write.</param>
+        /// <param name="values">Tag-value pairs to write.</param>
-        /// <param name="flagAddress">The address of the flag tag to write.</param>
+        /// <param name="flagTag">Tag to poll after writes.</param>
-        /// <param name="flagValue">The value to write to the flag tag.</param>
+        /// <param name="flagValue">Expected value (type-aware comparison).</param>
-        /// <param name="responseAddress">The address of the response tag to monitor.</param>
+        /// <param name="timeoutMs">Max wait time in milliseconds.</param>
-        /// <param name="responseValue">The expected value of the response tag.</param>
+        /// <param name="pollIntervalMs">Poll interval in milliseconds.</param>
-        /// <param name="ct">Cancellation token controlling the wait.</param>
+        /// <param name="ct">Cancellation token.</param>
-        /// <returns>
+        Task<(bool flagReached, int elapsedMs)> WriteBatchAndWaitAsync(
-        ///     <c>true</c> if the response value was observed before cancellation;
-        ///     otherwise <c>false</c>.
-        /// </returns>
-        Task<bool> WriteBatchAndWaitAsync(
             IReadOnlyDictionary<string, object> values,
-            string flagAddress,
+            string flagTag,
             object flagValue,
-            string responseAddress,
+            int timeoutMs,
-            object responseValue,
+            int pollIntervalMs,
             CancellationToken ct = default);
 
-        /// <summary>
+        /// <summary>Subscribes to value changes for specified addresses.</summary>
-        ///     Subscribes to value changes for specified addresses.
-        /// </summary>
-        /// <param name="addresses">The tag addresses to monitor.</param>
-        /// <param name="callback">Callback for value changes.</param>
-        /// <param name="ct">Cancellation token.</param>
         /// <returns>Subscription handle for unsubscribing.</returns>
-        Task<IAsyncDisposable> SubscribeAsync(IEnumerable<string> addresses, Action<string, Vtq> callback,
+        Task<IAsyncDisposable> SubscribeAsync(
+            IEnumerable<string> addresses,
+            Action<string, Vtq> callback,
             CancellationToken ct = default);
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/Quality.cs

@@ -2,123 +2,126 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
 {
     /// <summary>
     ///     OPC quality codes mapped to domain-level values.
-    ///     The byte value matches the low-order byte of the OPC UA StatusCode,
+    ///     The byte value matches the low-order byte of the OPC DA quality code,
-    ///     so it can be persisted or round-tripped without translation.
+    ///     enabling direct round-trip between the domain enum and the wire OPC DA byte.
     /// </summary>
     public enum Quality : byte
     {
         // ─────────────── Bad family (0-31) ───────────────
-        /// <summary>0x00 – Bad [Non-Specific]</summary>
+        /// <summary>0x00 - Bad [Non-Specific]</summary>
         Bad = 0,
 
-        /// <summary>0x01 – Unknown quality value</summary>
+        /// <summary>0x01 - Unknown quality value</summary>
         Unknown = 1,
 
-        /// <summary>0x04 – Bad [Configuration Error]</summary>
+        /// <summary>0x04 - Bad [Configuration Error]</summary>
         Bad_ConfigError = 4,
 
-        /// <summary>0x08 – Bad [Not Connected]</summary>
+        /// <summary>0x08 - Bad [Not Connected]</summary>
         Bad_NotConnected = 8,
 
-        /// <summary>0x0C – Bad [Device Failure]</summary>
+        /// <summary>0x0C - Bad [Device Failure]</summary>
         Bad_DeviceFailure = 12,
 
-        /// <summary>0x10 – Bad [Sensor Failure]</summary>
+        /// <summary>0x10 - Bad [Sensor Failure]</summary>
         Bad_SensorFailure = 16,
 
-        /// <summary>0x14 – Bad [Last Known Value]</summary>
+        /// <summary>0x14 - Bad [Last Known Value]</summary>
         Bad_LastKnownValue = 20,
 
-        /// <summary>0x18 – Bad [Communication Failure]</summary>
+        /// <summary>0x18 - Bad [Communication Failure]</summary>
         Bad_CommFailure = 24,
 
-        /// <summary>0x1C – Bad [Out of Service]</summary>
+        /// <summary>0x1C - Bad [Out of Service]</summary>
         Bad_OutOfService = 28,
 
+        /// <summary>0x20 - Bad [Waiting for Initial Data]</summary>
+        Bad_WaitingForInitialData = 32,
+
         // ──────────── Uncertain family (64-95) ───────────
-        /// <summary>0x40 – Uncertain [Non-Specific]</summary>
+        /// <summary>0x40 - Uncertain [Non-Specific]</summary>
         Uncertain = 64,
 
-        /// <summary>0x41 – Uncertain [Non-Specific] (Low Limited)</summary>
+        /// <summary>0x41 - Uncertain [Non-Specific] (Low Limited)</summary>
         Uncertain_LowLimited = 65,
 
-        /// <summary>0x42 – Uncertain [Non-Specific] (High Limited)</summary>
+        /// <summary>0x42 - Uncertain [Non-Specific] (High Limited)</summary>
         Uncertain_HighLimited = 66,
 
-        /// <summary>0x43 – Uncertain [Non-Specific] (Constant)</summary>
+        /// <summary>0x43 - Uncertain [Non-Specific] (Constant)</summary>
         Uncertain_Constant = 67,
 
-        /// <summary>0x44 – Uncertain [Last Usable]</summary>
+        /// <summary>0x44 - Uncertain [Last Usable]</summary>
         Uncertain_LastUsable = 68,
 
-        /// <summary>0x45 – Uncertain [Last Usable] (Low Limited)</summary>
+        /// <summary>0x45 - Uncertain [Last Usable] (Low Limited)</summary>
         Uncertain_LastUsable_LL = 69,
 
-        /// <summary>0x46 – Uncertain [Last Usable] (High Limited)</summary>
+        /// <summary>0x46 - Uncertain [Last Usable] (High Limited)</summary>
         Uncertain_LastUsable_HL = 70,
 
-        /// <summary>0x47 – Uncertain [Last Usable] (Constant)</summary>
+        /// <summary>0x47 - Uncertain [Last Usable] (Constant)</summary>
         Uncertain_LastUsable_Cnst = 71,
 
-        /// <summary>0x50 – Uncertain [Sensor Not Accurate]</summary>
+        /// <summary>0x50 - Uncertain [Sensor Not Accurate]</summary>
         Uncertain_SensorNotAcc = 80,
 
-        /// <summary>0x51 – Uncertain [Sensor Not Accurate] (Low Limited)</summary>
+        /// <summary>0x51 - Uncertain [Sensor Not Accurate] (Low Limited)</summary>
         Uncertain_SensorNotAcc_LL = 81,
 
-        /// <summary>0x52 – Uncertain [Sensor Not Accurate] (High Limited)</summary>
+        /// <summary>0x52 - Uncertain [Sensor Not Accurate] (High Limited)</summary>
         Uncertain_SensorNotAcc_HL = 82,
 
-        /// <summary>0x53 – Uncertain [Sensor Not Accurate] (Constant)</summary>
+        /// <summary>0x53 - Uncertain [Sensor Not Accurate] (Constant)</summary>
         Uncertain_SensorNotAcc_C = 83,
 
-        /// <summary>0x54 – Uncertain [EU Exceeded]</summary>
+        /// <summary>0x54 - Uncertain [EU Exceeded]</summary>
         Uncertain_EuExceeded = 84,
 
-        /// <summary>0x55 – Uncertain [EU Exceeded] (Low Limited)</summary>
+        /// <summary>0x55 - Uncertain [EU Exceeded] (Low Limited)</summary>
         Uncertain_EuExceeded_LL = 85,
 
-        /// <summary>0x56 – Uncertain [EU Exceeded] (High Limited)</summary>
+        /// <summary>0x56 - Uncertain [EU Exceeded] (High Limited)</summary>
         Uncertain_EuExceeded_HL = 86,
 
-        /// <summary>0x57 – Uncertain [EU Exceeded] (Constant)</summary>
+        /// <summary>0x57 - Uncertain [EU Exceeded] (Constant)</summary>
         Uncertain_EuExceeded_C = 87,
 
-        /// <summary>0x58 – Uncertain [Sub-Normal]</summary>
+        /// <summary>0x58 - Uncertain [Sub-Normal]</summary>
         Uncertain_SubNormal = 88,
 
-        /// <summary>0x59 – Uncertain [Sub-Normal] (Low Limited)</summary>
+        /// <summary>0x59 - Uncertain [Sub-Normal] (Low Limited)</summary>
         Uncertain_SubNormal_LL = 89,
 
-        /// <summary>0x5A – Uncertain [Sub-Normal] (High Limited)</summary>
+        /// <summary>0x5A - Uncertain [Sub-Normal] (High Limited)</summary>
         Uncertain_SubNormal_HL = 90,
 
-        /// <summary>0x5B – Uncertain [Sub-Normal] (Constant)</summary>
+        /// <summary>0x5B - Uncertain [Sub-Normal] (Constant)</summary>
         Uncertain_SubNormal_C = 91,
 
         // ─────────────── Good family (192-219) ────────────
-        /// <summary>0xC0 – Good [Non-Specific]</summary>
+        /// <summary>0xC0 - Good [Non-Specific]</summary>
         Good = 192,
 
-        /// <summary>0xC1 – Good [Non-Specific] (Low Limited)</summary>
+        /// <summary>0xC1 - Good [Non-Specific] (Low Limited)</summary>
         Good_LowLimited = 193,
 
-        /// <summary>0xC2 – Good [Non-Specific] (High Limited)</summary>
+        /// <summary>0xC2 - Good [Non-Specific] (High Limited)</summary>
         Good_HighLimited = 194,
 
-        /// <summary>0xC3 – Good [Non-Specific] (Constant)</summary>
+        /// <summary>0xC3 - Good [Non-Specific] (Constant)</summary>
         Good_Constant = 195,
 
-        /// <summary>0xD8 – Good [Local Override]</summary>
+        /// <summary>0xD8 - Good [Local Override]</summary>
         Good_LocalOverride = 216,
 
-        /// <summary>0xD9 – Good [Local Override] (Low Limited)</summary>
+        /// <summary>0xD9 - Good [Local Override] (Low Limited)</summary>
         Good_LocalOverride_LL = 217,
 
-        /// <summary>0xDA – Good [Local Override] (High Limited)</summary>
+        /// <summary>0xDA - Good [Local Override] (High Limited)</summary>
         Good_LocalOverride_HL = 218,
 
-        /// <summary>0xDB – Good [Local Override] (Constant)</summary>
+        /// <summary>0xDB - Good [Local Override] (Constant)</summary>
         Good_LocalOverride_C = 219
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/QualityCodeMapper.cs

@@ -0,0 +1,167 @@
+using System.Collections.Generic;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Maps between the domain <see cref="Quality"/> enum and proto QualityCode messages.
+    ///     status_code (uint32) is canonical. symbolic_name is derived from a lookup table.
+    /// </summary>
+    public static class QualityCodeMapper
+    {
+        /// <summary>OPC UA status code → symbolic name lookup.</summary>
+        private static readonly Dictionary<uint, string> StatusCodeToName = new Dictionary<uint, string>
+        {
+            // Good
+            { 0x00000000, "Good" },
+            { 0x00D80000, "GoodLocalOverride" },
+
+            // Uncertain
+            { 0x40900000, "UncertainLastUsableValue" },
+            { 0x42390000, "UncertainSensorNotAccurate" },
+            { 0x40540000, "UncertainEngineeringUnitsExceeded" },
+            { 0x40580000, "UncertainSubNormal" },
+
+            // Bad
+            { 0x80000000, "Bad" },
+            { 0x80040000, "BadConfigurationError" },
+            { 0x808A0000, "BadNotConnected" },
+            { 0x806B0000, "BadDeviceFailure" },
+            { 0x806D0000, "BadSensorFailure" },
+            { 0x80050000, "BadCommunicationFailure" },
+            { 0x808F0000, "BadOutOfService" },
+            { 0x80320000, "BadWaitingForInitialData" },
+        };
+
+        /// <summary>Domain Quality enum → OPC UA status code.</summary>
+        private static readonly Dictionary<Quality, uint> QualityToStatusCode = new Dictionary<Quality, uint>
+        {
+            // Good family
+            { Quality.Good, 0x00000000 },
+            { Quality.Good_LowLimited, 0x00000000 },
+            { Quality.Good_HighLimited, 0x00000000 },
+            { Quality.Good_Constant, 0x00000000 },
+            { Quality.Good_LocalOverride, 0x00D80000 },
+            { Quality.Good_LocalOverride_LL, 0x00D80000 },
+            { Quality.Good_LocalOverride_HL, 0x00D80000 },
+            { Quality.Good_LocalOverride_C, 0x00D80000 },
+
+            // Uncertain family
+            { Quality.Uncertain, 0x40900000 },
+            { Quality.Uncertain_LowLimited, 0x40900000 },
+            { Quality.Uncertain_HighLimited, 0x40900000 },
+            { Quality.Uncertain_Constant, 0x40900000 },
+            { Quality.Uncertain_LastUsable, 0x40900000 },
+            { Quality.Uncertain_LastUsable_LL, 0x40900000 },
+            { Quality.Uncertain_LastUsable_HL, 0x40900000 },
+            { Quality.Uncertain_LastUsable_Cnst, 0x40900000 },
+            { Quality.Uncertain_SensorNotAcc, 0x42390000 },
+            { Quality.Uncertain_SensorNotAcc_LL, 0x42390000 },
+            { Quality.Uncertain_SensorNotAcc_HL, 0x42390000 },
+            { Quality.Uncertain_SensorNotAcc_C, 0x42390000 },
+            { Quality.Uncertain_EuExceeded, 0x40540000 },
+            { Quality.Uncertain_EuExceeded_LL, 0x40540000 },
+            { Quality.Uncertain_EuExceeded_HL, 0x40540000 },
+            { Quality.Uncertain_EuExceeded_C, 0x40540000 },
+            { Quality.Uncertain_SubNormal, 0x40580000 },
+            { Quality.Uncertain_SubNormal_LL, 0x40580000 },
+            { Quality.Uncertain_SubNormal_HL, 0x40580000 },
+            { Quality.Uncertain_SubNormal_C, 0x40580000 },
+
+            // Bad family
+            { Quality.Bad, 0x80000000 },
+            { Quality.Unknown, 0x80000000 },
+            { Quality.Bad_ConfigError, 0x80040000 },
+            { Quality.Bad_NotConnected, 0x808A0000 },
+            { Quality.Bad_DeviceFailure, 0x806B0000 },
+            { Quality.Bad_SensorFailure, 0x806D0000 },
+            { Quality.Bad_LastKnownValue, 0x80050000 },
+            { Quality.Bad_CommFailure, 0x80050000 },
+            { Quality.Bad_OutOfService, 0x808F0000 },
+            { Quality.Bad_WaitingForInitialData, 0x80320000 },
+        };
+
+        /// <summary>
+        ///     Converts a domain Quality enum to a proto QualityCode message.
+        /// </summary>
+        public static Scada.QualityCode ToQualityCode(Quality quality)
+        {
+            var statusCode = QualityToStatusCode.TryGetValue(quality, out var code) ? code : 0x80000000u;
+            var symbolicName = StatusCodeToName.TryGetValue(statusCode, out var name) ? name : "Bad";
+
+            return new Scada.QualityCode
+            {
+                StatusCode = statusCode,
+                SymbolicName = symbolicName
+            };
+        }
+
+        /// <summary>OPC UA status code → primary domain Quality (reverse lookup).</summary>
+        private static readonly Dictionary<uint, Quality> StatusCodeToQuality = new Dictionary<uint, Quality>
+        {
+            // Good
+            { 0x00000000, Quality.Good },
+            { 0x00D80000, Quality.Good_LocalOverride },
+
+            // Uncertain — pick the most specific base variant
+            { 0x40900000, Quality.Uncertain_LastUsable },
+            { 0x42390000, Quality.Uncertain_SensorNotAcc },
+            { 0x40540000, Quality.Uncertain_EuExceeded },
+            { 0x40580000, Quality.Uncertain_SubNormal },
+
+            // Bad
+            { 0x80000000, Quality.Bad },
+            { 0x80040000, Quality.Bad_ConfigError },
+            { 0x808A0000, Quality.Bad_NotConnected },
+            { 0x806B0000, Quality.Bad_DeviceFailure },
+            { 0x806D0000, Quality.Bad_SensorFailure },
+            { 0x80050000, Quality.Bad_CommFailure },
+            { 0x808F0000, Quality.Bad_OutOfService },
+            { 0x80320000, Quality.Bad_WaitingForInitialData },
+        };
+
+        /// <summary>
+        ///     Converts an OPC UA status code (uint32) to a domain Quality enum.
+        ///     Falls back to the nearest category if the specific code is not mapped.
+        /// </summary>
+        public static Quality FromStatusCode(uint statusCode)
+        {
+            if (StatusCodeToQuality.TryGetValue(statusCode, out var quality))
+                return quality;
+
+            // Category fallback
+            uint category = statusCode & 0xC0000000;
+            if (category == 0x00000000) return Quality.Good;
+            if (category == 0x40000000) return Quality.Uncertain;
+            return Quality.Bad;
+        }
+
+        /// <summary>
+        ///     Gets the symbolic name for a status code.
+        /// </summary>
+        public static string GetSymbolicName(uint statusCode)
+        {
+            if (StatusCodeToName.TryGetValue(statusCode, out var name))
+                return name;
+
+            uint category = statusCode & 0xC0000000;
+            if (category == 0x00000000) return "Good";
+            if (category == 0x40000000) return "Uncertain";
+            return "Bad";
+        }
+
+        /// <summary>
+        ///     Creates a QualityCode for a specific well-known status.
+        /// </summary>
+        public static Scada.QualityCode Good() => new Scada.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" };
+        public static Scada.QualityCode Bad() => new Scada.QualityCode { StatusCode = 0x80000000, SymbolicName = "Bad" };
+        public static Scada.QualityCode BadConfigurationError() => new Scada.QualityCode { StatusCode = 0x80040000, SymbolicName = "BadConfigurationError" };
+        public static Scada.QualityCode BadCommunicationFailure() => new Scada.QualityCode { StatusCode = 0x80050000, SymbolicName = "BadCommunicationFailure" };
+        public static Scada.QualityCode BadNotConnected() => new Scada.QualityCode { StatusCode = 0x808A0000, SymbolicName = "BadNotConnected" };
+        public static Scada.QualityCode BadDeviceFailure() => new Scada.QualityCode { StatusCode = 0x806B0000, SymbolicName = "BadDeviceFailure" };
+        public static Scada.QualityCode BadSensorFailure() => new Scada.QualityCode { StatusCode = 0x806D0000, SymbolicName = "BadSensorFailure" };
+        public static Scada.QualityCode BadOutOfService() => new Scada.QualityCode { StatusCode = 0x808F0000, SymbolicName = "BadOutOfService" };
+        public static Scada.QualityCode BadWaitingForInitialData() => new Scada.QualityCode { StatusCode = 0x80320000, SymbolicName = "BadWaitingForInitialData" };
+        public static Scada.QualityCode GoodLocalOverride() => new Scada.QualityCode { StatusCode = 0x00D80000, SymbolicName = "GoodLocalOverride" };
+        public static Scada.QualityCode UncertainLastUsableValue() => new Scada.QualityCode { StatusCode = 0x40900000, SymbolicName = "UncertainLastUsableValue" };
+    }
+}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/QualityExtensions.cs

@@ -0,0 +1,17 @@
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Extension methods for the <see cref="Quality"/> enum.
+    /// </summary>
+    public static class QualityExtensions
+    {
+        /// <summary>Returns true if quality is in the Good family (byte >= 192).</summary>
+        public static bool IsGood(this Quality q) => (byte)q >= 192;
+
+        /// <summary>Returns true if quality is in the Uncertain family (byte 64-127).</summary>
+        public static bool IsUncertain(this Quality q) => (byte)q >= 64 && (byte)q < 128;
+
+        /// <summary>Returns true if quality is in the Bad family (byte < 64).</summary>
+        public static bool IsBad(this Quality q) => (byte)q < 64;
+    }
+}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/TypedValueConverter.cs

@@ -0,0 +1,211 @@
+using System;
+using Google.Protobuf;
+using Serilog;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Converts between COM variant objects (boxed .NET types from MxAccess)
+    ///     and proto-generated <see cref="Scada.TypedValue"/> messages.
+    /// </summary>
+    public static class TypedValueConverter
+    {
+        private static readonly ILogger Log = Serilog.Log.ForContext(typeof(TypedValueConverter));
+
+        /// <summary>
+        ///     Converts a COM variant object to a proto TypedValue.
+        ///     Returns null (unset TypedValue) for null, DBNull, or VT_EMPTY/VT_NULL.
+        /// </summary>
+        public static Scada.TypedValue? ToTypedValue(object? value)
+        {
+            if (value == null || value is DBNull)
+                return null;
+
+            switch (value)
+            {
+                case bool b:
+                    return new Scada.TypedValue { BoolValue = b };
+
+                case short s:       // VT_I2 → widened to int32
+                    return new Scada.TypedValue { Int32Value = s };
+
+                case int i:         // VT_I4
+                    return new Scada.TypedValue { Int32Value = i };
+
+                case long l:        // VT_I8
+                    return new Scada.TypedValue { Int64Value = l };
+
+                case ushort us:     // VT_UI2 → widened to int32
+                    return new Scada.TypedValue { Int32Value = us };
+
+                case uint ui:       // VT_UI4 → widened to int64 to avoid sign issues
+                    return new Scada.TypedValue { Int64Value = ui };
+
+                case ulong ul:      // VT_UI8 → int64, truncation risk
+                    if (ul > (ulong)long.MaxValue)
+                        Log.Warning("ulong value {Value} exceeds long.MaxValue, truncation will occur", ul);
+                    return new Scada.TypedValue { Int64Value = (long)ul };
+
+                case float f:       // VT_R4
+                    return new Scada.TypedValue { FloatValue = f };
+
+                case double d:      // VT_R8
+                    return new Scada.TypedValue { DoubleValue = d };
+
+                case string str:    // VT_BSTR
+                    return new Scada.TypedValue { StringValue = str };
+
+                case DateTime dt:   // VT_DATE → UTC Ticks
+                    return new Scada.TypedValue { DatetimeValue = dt.ToUniversalTime().Ticks };
+
+                case decimal dec:   // VT_DECIMAL → double (precision loss)
+                    Log.Warning("Decimal value {Value} converted to double, precision loss may occur", dec);
+                    return new Scada.TypedValue { DoubleValue = (double)dec };
+
+                case byte[] bytes:  // VT_ARRAY of bytes
+                    return new Scada.TypedValue { BytesValue = ByteString.CopyFrom(bytes) };
+
+                case bool[] boolArr:
+                {
+                    var arr = new Scada.BoolArray();
+                    arr.Values.AddRange(boolArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { BoolValues = arr } };
+                }
+
+                case int[] intArr:
+                {
+                    var arr = new Scada.Int32Array();
+                    arr.Values.AddRange(intArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { Int32Values = arr } };
+                }
+
+                case long[] longArr:
+                {
+                    var arr = new Scada.Int64Array();
+                    arr.Values.AddRange(longArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { Int64Values = arr } };
+                }
+
+                case float[] floatArr:
+                {
+                    var arr = new Scada.FloatArray();
+                    arr.Values.AddRange(floatArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { FloatValues = arr } };
+                }
+
+                case double[] doubleArr:
+                {
+                    var arr = new Scada.DoubleArray();
+                    arr.Values.AddRange(doubleArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { DoubleValues = arr } };
+                }
+
+                case string[] strArr:
+                {
+                    var arr = new Scada.StringArray();
+                    arr.Values.AddRange(strArr);
+                    return new Scada.TypedValue { ArrayValue = new Scada.ArrayValue { StringValues = arr } };
+                }
+
+                default:
+                    // VT_UNKNOWN or any unrecognized type — ToString() fallback
+                    Log.Warning("Unrecognized COM variant type {Type}, using ToString() fallback", value.GetType().Name);
+                    return new Scada.TypedValue { StringValue = value.ToString() };
+            }
+        }
+
+        /// <summary>
+        ///     Converts a proto TypedValue back to a boxed .NET object.
+        ///     Returns null for unset oneof (null TypedValue or ValueCase.None).
+        /// </summary>
+        public static object? FromTypedValue(Scada.TypedValue? typedValue)
+        {
+            if (typedValue == null)
+                return null;
+
+            switch (typedValue.ValueCase)
+            {
+                case Scada.TypedValue.ValueOneofCase.BoolValue:
+                    return typedValue.BoolValue;
+
+                case Scada.TypedValue.ValueOneofCase.Int32Value:
+                    return typedValue.Int32Value;
+
+                case Scada.TypedValue.ValueOneofCase.Int64Value:
+                    return typedValue.Int64Value;
+
+                case Scada.TypedValue.ValueOneofCase.FloatValue:
+                    return typedValue.FloatValue;
+
+                case Scada.TypedValue.ValueOneofCase.DoubleValue:
+                    return typedValue.DoubleValue;
+
+                case Scada.TypedValue.ValueOneofCase.StringValue:
+                    return typedValue.StringValue;
+
+                case Scada.TypedValue.ValueOneofCase.BytesValue:
+                    return typedValue.BytesValue.ToByteArray();
+
+                case Scada.TypedValue.ValueOneofCase.DatetimeValue:
+                    return new DateTime(typedValue.DatetimeValue, DateTimeKind.Utc);
+
+                case Scada.TypedValue.ValueOneofCase.ArrayValue:
+                    return FromArrayValue(typedValue.ArrayValue);
+
+                case Scada.TypedValue.ValueOneofCase.None:
+                default:
+                    return null;
+            }
+        }
+
+        private static object? FromArrayValue(Scada.ArrayValue? arrayValue)
+        {
+            if (arrayValue == null)
+                return null;
+
+            switch (arrayValue.ValuesCase)
+            {
+                case Scada.ArrayValue.ValuesOneofCase.BoolValues:
+                    return arrayValue.BoolValues?.Values?.Count > 0
+                        ? ToArray(arrayValue.BoolValues.Values)
+                        : Array.Empty<bool>();
+
+                case Scada.ArrayValue.ValuesOneofCase.Int32Values:
+                    return arrayValue.Int32Values?.Values?.Count > 0
+                        ? ToArray(arrayValue.Int32Values.Values)
+                        : Array.Empty<int>();
+
+                case Scada.ArrayValue.ValuesOneofCase.Int64Values:
+                    return arrayValue.Int64Values?.Values?.Count > 0
+                        ? ToArray(arrayValue.Int64Values.Values)
+                        : Array.Empty<long>();
+
+                case Scada.ArrayValue.ValuesOneofCase.FloatValues:
+                    return arrayValue.FloatValues?.Values?.Count > 0
+                        ? ToArray(arrayValue.FloatValues.Values)
+                        : Array.Empty<float>();
+
+                case Scada.ArrayValue.ValuesOneofCase.DoubleValues:
+                    return arrayValue.DoubleValues?.Values?.Count > 0
+                        ? ToArray(arrayValue.DoubleValues.Values)
+                        : Array.Empty<double>();
+
+                case Scada.ArrayValue.ValuesOneofCase.StringValues:
+                    return arrayValue.StringValues?.Values?.Count > 0
+                        ? ToArray(arrayValue.StringValues.Values)
+                        : Array.Empty<string>();
+
+                default:
+                    return null;
+            }
+        }
+
+        private static T[] ToArray<T>(Google.Protobuf.Collections.RepeatedField<T> repeatedField)
+        {
+            var result = new T[repeatedField.Count];
+            for (int i = 0; i < repeatedField.Count; i++)
+                result[i] = repeatedField[i];
+            return result;
+        }
+    }
+}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Domain/Vtq.cs

@@ -7,27 +7,15 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
     /// </summary>
     public readonly struct Vtq : IEquatable<Vtq>
     {
-        /// <summary>
+        /// <summary>Gets the value. Null represents an unset/missing value.</summary>
-        ///     Gets the value.
-        /// </summary>
         public object? Value { get; }
 
-        /// <summary>
+        /// <summary>Gets the UTC timestamp when the value was read.</summary>
-        ///     Gets the timestamp when the value was read.
-        /// </summary>
         public DateTime Timestamp { get; }
 
-        /// <summary>
+        /// <summary>Gets the quality of the value.</summary>
-        ///     Gets the quality of the value.
-        /// </summary>
         public Quality Quality { get; }
 
-        /// <summary>
-        ///     Initializes a new instance of the <see cref="Vtq" /> struct.
-        /// </summary>
-        /// <param name="value">The value.</param>
-        /// <param name="timestamp">The timestamp when the value was read.</param>
-        /// <param name="quality">The quality of the value.</param>
         public Vtq(object? value, DateTime timestamp, Quality quality)
         {
             Value = value;
@@ -35,63 +23,17 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
             Quality = quality;
         }
 
-        /// <summary>
+        public static Vtq New(object? value, Quality quality) => new(value, DateTime.UtcNow, quality);
-        ///     Creates a new <see cref="Vtq" /> instance with the specified value and quality, using the current UTC timestamp.
+        public static Vtq New(object? value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
-        /// </summary>
-        /// <param name="value">The value.</param>
-        /// <param name="quality">The quality of the value.</param>
-        /// <returns>A new <see cref="Vtq" /> instance.</returns>
-        public static Vtq New(object value, Quality quality) => new(value, DateTime.UtcNow, quality);
-
-        /// <summary>
-        ///     Creates a new <see cref="Vtq" /> instance with the specified value, timestamp, and quality.
-        /// </summary>
-        /// <param name="value">The value.</param>
-        /// <param name="timestamp">The timestamp when the value was read.</param>
-        /// <param name="quality">The quality of the value.</param>
-        /// <returns>A new <see cref="Vtq" /> instance.</returns>
-        public static Vtq New(object value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
-
-        /// <summary>
-        ///     Creates a <see cref="Vtq" /> instance with good quality and the current UTC timestamp.
-        /// </summary>
-        /// <param name="value">The value.</param>
-        /// <returns>A new <see cref="Vtq" /> instance with good quality.</returns>
         public static Vtq Good(object value) => new(value, DateTime.UtcNow, Quality.Good);
-
-        /// <summary>
-        ///     Creates a <see cref="Vtq" /> instance with bad quality and the current UTC timestamp.
-        /// </summary>
-        /// <param name="value">The value. Optional.</param>
-        /// <returns>A new <see cref="Vtq" /> instance with bad quality.</returns>
         public static Vtq Bad(object? value = null) => new(value, DateTime.UtcNow, Quality.Bad);
-
-        /// <summary>
-        ///     Creates a <see cref="Vtq" /> instance with uncertain quality and the current UTC timestamp.
-        /// </summary>
-        /// <param name="value">The value.</param>
-        /// <returns>A new <see cref="Vtq" /> instance with uncertain quality.</returns>
         public static Vtq Uncertain(object value) => new(value, DateTime.UtcNow, Quality.Uncertain);
 
-        /// <summary>
-        ///     Determines whether the specified <see cref="Vtq" /> is equal to the current <see cref="Vtq" />.
-        /// </summary>
-        /// <param name="other">The <see cref="Vtq" /> to compare with the current <see cref="Vtq" />.</param>
-        /// <returns>true if the specified <see cref="Vtq" /> is equal to the current <see cref="Vtq" />; otherwise, false.</returns>
         public bool Equals(Vtq other) =>
             Equals(Value, other.Value) && Timestamp.Equals(other.Timestamp) && Quality == other.Quality;
 
-        /// <summary>
-        ///     Determines whether the specified object is equal to the current <see cref="Vtq" />.
-        /// </summary>
-        /// <param name="obj">The object to compare with the current <see cref="Vtq" />.</param>
-        /// <returns>true if the specified object is equal to the current <see cref="Vtq" />; otherwise, false.</returns>
         public override bool Equals(object obj) => obj is Vtq other && Equals(other);
 
-        /// <summary>
-        ///     Returns the hash code for this instance.
-        /// </summary>
-        /// <returns>A 32-bit signed integer hash code.</returns>
         public override int GetHashCode()
         {
             unchecked
@@ -103,27 +45,10 @@ namespace ZB.MOM.WW.LmxProxy.Host.Domain
             }
         }
 
-        /// <summary>
-        ///     Returns a string that represents the current object.
-        /// </summary>
-        /// <returns>A string that represents the current object.</returns>
         public override string ToString() =>
             $"{{Value={Value}, Timestamp={Timestamp:yyyy-MM-dd HH:mm:ss.fff}, Quality={Quality}}}";
 
-        /// <summary>
-        ///     Determines whether two specified instances of <see cref="Vtq" /> are equal.
-        /// </summary>
-        /// <param name="left">The first <see cref="Vtq" /> to compare.</param>
-        /// <param name="right">The second <see cref="Vtq" /> to compare.</param>
-        /// <returns>true if left and right are equal; otherwise, false.</returns>
         public static bool operator ==(Vtq left, Vtq right) => left.Equals(right);
-
-        /// <summary>
-        ///     Determines whether two specified instances of <see cref="Vtq" /> are not equal.
-        /// </summary>
-        /// <param name="left">The first <see cref="Vtq" /> to compare.</param>
-        /// <param name="right">The second <see cref="Vtq" /> to compare.</param>
-        /// <returns>true if left and right are not equal; otherwise, false.</returns>
         public static bool operator !=(Vtq left, Vtq right) => !left.Equals(right);
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Grpc/Protos/scada.proto

@@ -1,33 +1,71 @@
 syntax = "proto3";
-
-option csharp_namespace = "ZB.MOM.WW.LmxProxy.Host.Grpc";
-
 package scada;
 
-// The SCADA service definition
+// ============================================================
+// Service Definition
+// ============================================================
+
 service ScadaService {
-  // Connection management
   rpc Connect(ConnectRequest) returns (ConnectResponse);
   rpc Disconnect(DisconnectRequest) returns (DisconnectResponse);
   rpc GetConnectionState(GetConnectionStateRequest) returns (GetConnectionStateResponse);
-
-  // Read operations
   rpc Read(ReadRequest) returns (ReadResponse);
   rpc ReadBatch(ReadBatchRequest) returns (ReadBatchResponse);
-
-  // Write operations
   rpc Write(WriteRequest) returns (WriteResponse);
   rpc WriteBatch(WriteBatchRequest) returns (WriteBatchResponse);
   rpc WriteBatchAndWait(WriteBatchAndWaitRequest) returns (WriteBatchAndWaitResponse);
-
-  // Subscription operations (server streaming) - now streams VtqMessage directly
   rpc Subscribe(SubscribeRequest) returns (stream VtqMessage);
-
-  // Authentication
   rpc CheckApiKey(CheckApiKeyRequest) returns (CheckApiKeyResponse);
 }
 
-// === CONNECTION MESSAGES ===
+// ============================================================
+// Typed Value System
+// ============================================================
+
+message TypedValue {
+  oneof value {
+    bool       bool_value     = 1;
+    int32      int32_value    = 2;
+    int64      int64_value    = 3;
+    float      float_value    = 4;
+    double     double_value   = 5;
+    string     string_value   = 6;
+    bytes      bytes_value    = 7;
+    int64      datetime_value = 8;   // UTC DateTime.Ticks (100ns intervals since 0001-01-01)
+    ArrayValue array_value    = 9;
+  }
+}
+
+message ArrayValue {
+  oneof values {
+    BoolArray   bool_values   = 1;
+    Int32Array  int32_values  = 2;
+    Int64Array  int64_values  = 3;
+    FloatArray  float_values  = 4;
+    DoubleArray double_values = 5;
+    StringArray string_values = 6;
+  }
+}
+
+message BoolArray   { repeated bool   values = 1; }
+message Int32Array  { repeated int32  values = 1; }
+message Int64Array  { repeated int64  values = 1; }
+message FloatArray  { repeated float  values = 1; }
+message DoubleArray { repeated double values = 1; }
+message StringArray { repeated string values = 1; }
+
+// ============================================================
+// OPC UA-Style Quality Codes
+// ============================================================
+
+message QualityCode {
+  uint32 status_code   = 1;
+  string symbolic_name = 2;
+}
+
+// ============================================================
+// Connection Lifecycle
+// ============================================================
 
 message ConnectRequest {
   string client_id = 1;
@@ -59,16 +97,29 @@ message GetConnectionStateResponse {
   int64  connected_since_utc_ticks = 3;
 }
 
-// === VTQ MESSAGE ===
+message CheckApiKeyRequest {
+  string api_key = 1;
+}
+
+message CheckApiKeyResponse {
+  bool   is_valid = 1;
+  string message  = 2;
+}
+
+// ============================================================
+// Value-Timestamp-Quality
+// ============================================================
 
 message VtqMessage {
   string      tag                 = 1;
-  string value = 2;
+  TypedValue  value               = 2;
   int64       timestamp_utc_ticks = 3;
-  string quality = 4;  // "Good", "Uncertain", "Bad"
+  QualityCode quality             = 4;
 }
 
-// === READ MESSAGES ===
+// ============================================================
+// Read Operations
+// ============================================================
 
 message ReadRequest {
   string session_id = 1;
@@ -92,12 +143,14 @@ message ReadBatchResponse {
   repeated VtqMessage  vtqs    = 3;
 }
 
-// === WRITE MESSAGES ===
+// ============================================================
+// Write Operations
+// ============================================================
 
 message WriteRequest {
   string     session_id = 1;
   string     tag        = 2;
-  string value = 3;
+  TypedValue value      = 3;
 }
 
 message WriteResponse {
@@ -107,7 +160,7 @@ message WriteResponse {
 
 message WriteItem {
   string     tag   = 1;
-  string value = 2;
+  TypedValue value = 2;
 }
 
 message WriteResult {
@@ -127,11 +180,15 @@ message WriteBatchResponse {
   repeated WriteResult results = 3;
 }
 
+// ============================================================
+// WriteBatchAndWait
+// ============================================================
+
 message WriteBatchAndWaitRequest {
   string             session_id       = 1;
   repeated WriteItem items            = 2;
   string             flag_tag         = 3;
-  string flag_value = 4;
+  TypedValue         flag_value       = 4;
   int32              timeout_ms       = 5;
   int32              poll_interval_ms = 6;
 }
@@ -144,23 +201,12 @@ message WriteBatchAndWaitResponse {
   int32                elapsed_ms    = 5;
 }
 
-// === SUBSCRIPTION MESSAGES ===
+// ============================================================
+// Subscription
+// ============================================================
 
 message SubscribeRequest {
   string          session_id  = 1;
   repeated string tags        = 2;
   int32           sampling_ms = 3;
 }
-
-// Note: Subscribe RPC now streams VtqMessage directly (defined above)
-
-// === AUTHENTICATION MESSAGES ===
-
-message CheckApiKeyRequest {
-  string api_key = 1;
-}
-
-message CheckApiKeyResponse {
-  bool is_valid = 1;
-  string message = 2;
-}

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Program.cs

@@ -1,87 +1,10 @@
-using System;
-using System.IO;
-using Microsoft.Extensions.Configuration;
-using Serilog;
-using Topshelf;
-using ZB.MOM.WW.LmxProxy.Host.Configuration;
-
 namespace ZB.MOM.WW.LmxProxy.Host
 {
-    internal class Program
+    internal static class Program
     {
-        private static void Main(string[] args)
+        static void Main(string[] args)
         {
-            // Build configuration
+            // Placeholder - Phase 3 will implement full Topshelf startup.
-            IConfigurationRoot? configuration = new ConfigurationBuilder()
-                .SetBasePath(Directory.GetCurrentDirectory())
-                .AddJsonFile("appsettings.json", true, true)
-                .AddEnvironmentVariables()
-                .Build();
-
-            // Configure Serilog from appsettings.json
-            Log.Logger = new LoggerConfiguration()
-                .ReadFrom.Configuration(configuration)
-                .CreateLogger();
-
-            try
-            {
-                Log.Information("Starting ZB.MOM.WW.LmxProxy.Host");
-
-                // Load configuration
-                var config = new LmxProxyConfiguration();
-                configuration.Bind(config);
-
-                // Validate configuration
-                if (!ConfigurationValidator.ValidateAndLog(config))
-                {
-                    Log.Fatal("Configuration validation failed. Please check the configuration and try again.");
-                    Environment.ExitCode = 1;
-                    return;
-                }
-
-                // Configure and run the Windows service using TopShelf
-                TopshelfExitCode exitCode = HostFactory.Run(hostConfig =>
-                {
-                    hostConfig.Service<LmxProxyService>(serviceConfig =>
-                    {
-                        serviceConfig.ConstructUsing(() => new LmxProxyService(config));
-                        serviceConfig.WhenStarted(service => service.Start());
-                        serviceConfig.WhenStopped(service => service.Stop());
-                        serviceConfig.WhenPaused(service => service.Pause());
-                        serviceConfig.WhenContinued(service => service.Continue());
-                        serviceConfig.WhenShutdown(service => service.Shutdown());
-                    });
-
-                    hostConfig.UseSerilog(Log.Logger);
-
-                    hostConfig.SetServiceName("ZB.MOM.WW.LmxProxy.Host");
-                    hostConfig.SetDisplayName("SCADA Bridge LMX Proxy");
-                    hostConfig.SetDescription("Provides gRPC access to Archestra MxAccess for SCADA Bridge");
-
-                    hostConfig.StartAutomatically();
-                    hostConfig.EnableServiceRecovery(recoveryConfig =>
-                    {
-                        recoveryConfig.RestartService(config.ServiceRecovery.FirstFailureDelayMinutes);
-                        recoveryConfig.RestartService(config.ServiceRecovery.SecondFailureDelayMinutes);
-                        recoveryConfig.RestartService(config.ServiceRecovery.SubsequentFailureDelayMinutes);
-                        recoveryConfig.SetResetPeriod(config.ServiceRecovery.ResetPeriodDays);
-                    });
-
-                    hostConfig.OnException(ex => { Log.Fatal(ex, "Unhandled exception in service"); });
-                });
-
-                Log.Information("Service exited with code: {ExitCode}", exitCode);
-                Environment.ExitCode = (int)exitCode;
-            }
-            catch (Exception ex)
-            {
-                Log.Fatal(ex, "Failed to start service");
-                Environment.ExitCode = 1;
-            }
-            finally
-            {
-                Log.CloseAndFlush();
-            }
         }
     }
 }

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/ZB.MOM.WW.LmxProxy.Host.csproj

@@ -8,35 +8,37 @@
     <IsPackable>false</IsPackable>
     <RootNamespace>ZB.MOM.WW.LmxProxy.Host</RootNamespace>
     <AssemblyName>ZB.MOM.WW.LmxProxy.Host</AssemblyName>
-    <!-- Force x86 architecture for all configurations (required by ArchestrA.MXAccess) -->
     <PlatformTarget>x86</PlatformTarget>
     <Platforms>x86</Platforms>
     <Prefer32Bit>true</Prefer32Bit>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Grpc.Core" Version="2.46.6"/>
+    <PackageReference Include="Grpc.Core" Version="2.46.6" />
-    <PackageReference Include="Grpc.Tools" Version="2.51.0">
+    <PackageReference Include="Grpc.Tools" Version="2.68.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Google.Protobuf" Version="3.21.12"/>
+    <PackageReference Include="Google.Protobuf" Version="3.29.3" />
-    <PackageReference Include="Topshelf" Version="4.3.0"/>
+    <PackageReference Include="Topshelf" Version="4.3.0" />
-    <PackageReference Include="Topshelf.Serilog" Version="4.3.0"/>
+    <PackageReference Include="Topshelf.Serilog" Version="4.3.0" />
-    <PackageReference Include="Serilog" Version="2.10.0"/>
+    <PackageReference Include="Serilog" Version="2.10.0" />
-    <PackageReference Include="Serilog.Sinks.Console" Version="4.0.1"/>
+    <PackageReference Include="Serilog.Sinks.Console" Version="4.0.1" />
-    <PackageReference Include="Serilog.Sinks.File" Version="5.0.0"/>
+    <PackageReference Include="Serilog.Sinks.File" Version="5.0.0" />
-    <PackageReference Include="Serilog.Settings.Configuration" Version="3.3.0"/>
+    <PackageReference Include="Serilog.Settings.Configuration" Version="3.3.0" />
-    <PackageReference Include="Serilog.Formatting.Compact" Version="1.1.0"/>
+    <PackageReference Include="Serilog.Formatting.Compact" Version="1.1.0" />
-    <PackageReference Include="System.Threading.Channels" Version="4.7.1"/>
+    <PackageReference Include="Serilog.Enrichers.Environment" Version="2.2.0" />
-    <PackageReference Include="Microsoft.Extensions.Configuration" Version="3.1.32"/>
+    <PackageReference Include="Serilog.Enrichers.Thread" Version="3.1.0" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.32"/>
+    <PackageReference Include="System.Threading.Channels" Version="4.7.1" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration" Version="3.1.32" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.32" />
-    <PackageReference Include="Polly" Version="7.2.4"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="3.1.32" />
-    <PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks" Version="3.1.32"/>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.32" />
-    <PackageReference Include="System.Memory" Version="4.5.5"/>
+    <PackageReference Include="Polly" Version="7.2.4" />
-    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.7.1"/>
+    <PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks" Version="3.1.32" />
+    <PackageReference Include="System.Memory" Version="4.5.5" />
+    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.7.1" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
   </ItemGroup>
 
   <ItemGroup>
@@ -47,7 +49,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Protobuf Include="Grpc\Protos\*.proto" GrpcServices="Both"/>
+    <Protobuf Include="Grpc\Protos\*.proto" GrpcServices="Both" />
   </ItemGroup>
 
   <ItemGroup>
@@ -57,9 +59,6 @@
     <None Update="appsettings.*.json">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
-    <None Update="App.config">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
   </ItemGroup>
 
 </Project>

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/appsettings.json

@@ -1,84 +1,2 @@
 {
-  "GrpcPort": 50051,
-  "ApiKeyConfigFile": "apikeys.json",
-  "Subscription": {
-    "ChannelCapacity": 1000,
-    "ChannelFullMode": "DropOldest"
-  },
-  "ServiceRecovery": {
-    "FirstFailureDelayMinutes": 1,
-    "SecondFailureDelayMinutes": 5,
-    "SubsequentFailureDelayMinutes": 10,
-    "ResetPeriodDays": 1
-  },
-  "Connection": {
-    "MonitorIntervalSeconds": 5,
-    "ConnectionTimeoutSeconds": 30,
-    "AutoReconnect": true,
-    "ReadTimeoutSeconds": 5,
-    "WriteTimeoutSeconds": 5,
-    "MaxConcurrentOperations": 10
-  },
-  "PerformanceMetrics": {
-    "ReportingIntervalSeconds": 60,
-    "Enabled": true,
-    "MaxSamplesPerMetric": 1000
-  },
-  "HealthCheck": {
-    "Enabled": true,
-    "TestTagAddress": "TestChannel.TestDevice.TestTag",
-    "MaxStaleDataMinutes": 5
-  },
-  "RetryPolicies": {
-    "ReadRetryCount": 3,
-    "WriteRetryCount": 3,
-    "ConnectionRetryCount": 5,
-    "CircuitBreakerThreshold": 5,
-    "CircuitBreakerDurationSeconds": 30
-  },
-  "Tls": {
-    "Enabled": true,
-    "ServerCertificatePath": "certs/server.crt",
-    "ServerKeyPath": "certs/server.key",
-    "ClientCaCertificatePath": "certs/ca.crt",
-    "RequireClientCertificate": false,
-    "CheckCertificateRevocation": false
-  },
-  "WebServer": {
-    "Enabled": true,
-    "Port": 8080
-  },
-  "Serilog": {
-    "MinimumLevel": {
-      "Default": "Information",
-      "Override": {
-        "Microsoft": "Warning",
-        "System": "Warning",
-        "Grpc": "Information"
-      }
-    },
-    "WriteTo": [
-      {
-        "Name": "Console",
-        "Args": {
-          "theme": "Serilog.Sinks.SystemConsole.Themes.AnsiConsoleTheme::Code, Serilog.Sinks.Console",
-          "outputTemplate": "[{Timestamp:HH:mm:ss} {Level:u3}] {Message:lj} {Properties:j}{NewLine}{Exception}"
-        }
-      },
-      {
-        "Name": "File",
-        "Args": {
-          "path": "logs/lmxproxy-.txt",
-          "rollingInterval": "Day",
-          "retainedFileCountLimit": 30,
-          "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] {SourceContext} {Message:lj}{NewLine}{Exception}"
-        }
-      }
-    ],
-    "Enrich": [
-      "FromLogContext",
-      "WithMachineName",
-      "WithThreadId"
-    ]
-  }
 }

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Client.Tests/CrossStack/CrossStackSerializationTests.cs

@@ -0,0 +1,270 @@
+using System.IO;
+using FluentAssertions;
+using Google.Protobuf;
+using ProtoBuf;
+using Xunit;
+using ProtoGenerated = Scada;
+using CodeFirst = ZB.MOM.WW.LmxProxy.Client.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Tests.CrossStack;
+
+/// <summary>
+/// Verifies wire compatibility between Host proto-generated types and Client code-first types.
+/// Serializes with one stack, deserializes with the other.
+/// </summary>
+public class CrossStackSerializationTests
+{
+    // ── Proto-generated → Code-first ──────────────────────────
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_BoolValue()
+    {
+        // Arrange: proto-generated VtqMessage with bool TypedValue
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Running",
+            Value = new ProtoGenerated.TypedValue { BoolValue = true },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        // Act: serialize with proto, deserialize with protobuf-net
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        // Assert
+        codeFirst.Should().NotBeNull();
+        codeFirst.Tag.Should().Be("Motor.Running");
+        codeFirst.Value.Should().NotBeNull();
+        codeFirst.Value!.BoolValue.Should().BeTrue();
+        codeFirst.TimestampUtcTicks.Should().Be(638789000000000000L);
+        codeFirst.Quality.Should().NotBeNull();
+        codeFirst.Quality!.StatusCode.Should().Be(0x00000000u);
+        codeFirst.Quality.SymbolicName.Should().Be("Good");
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_DoubleValue()
+    {
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Speed",
+            Value = new ProtoGenerated.TypedValue { DoubleValue = 42.5 },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        codeFirst.Value.Should().NotBeNull();
+        codeFirst.Value!.DoubleValue.Should().Be(42.5);
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_StringValue()
+    {
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Name",
+            Value = new ProtoGenerated.TypedValue { StringValue = "Pump A" },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        codeFirst.Value.Should().NotBeNull();
+        codeFirst.Value!.StringValue.Should().Be("Pump A");
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_Int32Value()
+    {
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Count",
+            Value = new ProtoGenerated.TypedValue { Int32Value = 2147483647 },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        codeFirst.Value!.Int32Value.Should().Be(int.MaxValue);
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_BadQuality()
+    {
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Fault",
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x806D0000, SymbolicName = "BadSensorFailure" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        codeFirst.Quality!.StatusCode.Should().Be(0x806D0000u);
+        codeFirst.Quality.SymbolicName.Should().Be("BadSensorFailure");
+        codeFirst.Quality.IsBad.Should().BeTrue();
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_NullValue()
+    {
+        // No Value field set — represents null
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Optional",
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x80000000, SymbolicName = "Bad" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        // When no oneof is set, the Value object may be null or all-default
+        // Either way, GetValueCase() should return None
+        if (codeFirst.Value != null)
+            codeFirst.Value.GetValueCase().Should().Be(CodeFirst.TypedValueCase.None);
+    }
+
+    [Fact]
+    public void VtqMessage_ProtoToCodeFirst_FloatArrayValue()
+    {
+        var floatArr = new ProtoGenerated.FloatArray();
+        floatArr.Values.AddRange(new[] { 1.0f, 2.0f, 3.0f });
+        var protoMsg = new ProtoGenerated.VtqMessage
+        {
+            Tag = "Motor.Samples",
+            Value = new ProtoGenerated.TypedValue
+            {
+                ArrayValue = new ProtoGenerated.ArrayValue { FloatValues = floatArr }
+            },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new ProtoGenerated.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.VtqMessage>(new MemoryStream(bytes));
+
+        codeFirst.Value.Should().NotBeNull();
+        codeFirst.Value!.ArrayValue.Should().NotBeNull();
+        codeFirst.Value.ArrayValue!.FloatValues.Should().NotBeNull();
+        codeFirst.Value.ArrayValue.FloatValues!.Values.Should().BeEquivalentTo(new[] { 1.0f, 2.0f, 3.0f });
+    }
+
+    // ── Code-first → Proto-generated ──────────────────────────
+
+    [Fact]
+    public void VtqMessage_CodeFirstToProto_DoubleValue()
+    {
+        var codeFirst = new CodeFirst.VtqMessage
+        {
+            Tag = "Motor.Speed",
+            Value = new CodeFirst.TypedValue { DoubleValue = 99.9 },
+            TimestampUtcTicks = 638789000000000000L,
+            Quality = new CodeFirst.QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" }
+        };
+
+        // Serialize with protobuf-net
+        var ms = new MemoryStream();
+        Serializer.Serialize(ms, codeFirst);
+        var bytes = ms.ToArray();
+
+        // Deserialize with Google.Protobuf
+        var protoMsg = ProtoGenerated.VtqMessage.Parser.ParseFrom(bytes);
+
+        protoMsg.Tag.Should().Be("Motor.Speed");
+        protoMsg.Value.Should().NotBeNull();
+        protoMsg.Value.DoubleValue.Should().Be(99.9);
+        protoMsg.TimestampUtcTicks.Should().Be(638789000000000000L);
+        protoMsg.Quality.StatusCode.Should().Be(0x00000000u);
+    }
+
+    [Fact]
+    public void WriteRequest_CodeFirstToProto()
+    {
+        var codeFirst = new CodeFirst.WriteRequest
+        {
+            SessionId = "abc123",
+            Tag = "Motor.Speed",
+            Value = new CodeFirst.TypedValue { DoubleValue = 42.5 }
+        };
+
+        var ms = new MemoryStream();
+        Serializer.Serialize(ms, codeFirst);
+        var bytes = ms.ToArray();
+
+        var protoMsg = ProtoGenerated.WriteRequest.Parser.ParseFrom(bytes);
+        protoMsg.SessionId.Should().Be("abc123");
+        protoMsg.Tag.Should().Be("Motor.Speed");
+        protoMsg.Value.Should().NotBeNull();
+        protoMsg.Value.DoubleValue.Should().Be(42.5);
+    }
+
+    [Fact]
+    public void ConnectRequest_RoundTrips()
+    {
+        var codeFirst = new CodeFirst.ConnectRequest { ClientId = "ScadaLink-1", ApiKey = "key-123" };
+        var ms = new MemoryStream();
+        Serializer.Serialize(ms, codeFirst);
+        var protoMsg = ProtoGenerated.ConnectRequest.Parser.ParseFrom(ms.ToArray());
+        protoMsg.ClientId.Should().Be("ScadaLink-1");
+        protoMsg.ApiKey.Should().Be("key-123");
+    }
+
+    [Fact]
+    public void ConnectResponse_RoundTrips()
+    {
+        var protoMsg = new ProtoGenerated.ConnectResponse
+        {
+            Success = true,
+            Message = "Connected",
+            SessionId = "abcdef1234567890abcdef1234567890"
+        };
+        var bytes = protoMsg.ToByteArray();
+        var codeFirst = Serializer.Deserialize<CodeFirst.ConnectResponse>(new MemoryStream(bytes));
+        codeFirst.Success.Should().BeTrue();
+        codeFirst.Message.Should().Be("Connected");
+        codeFirst.SessionId.Should().Be("abcdef1234567890abcdef1234567890");
+    }
+
+    [Fact]
+    public void WriteBatchAndWaitRequest_CodeFirstToProto_TypedFlagValue()
+    {
+        var codeFirst = new CodeFirst.WriteBatchAndWaitRequest
+        {
+            SessionId = "sess1",
+            FlagTag = "Motor.Done",
+            FlagValue = new CodeFirst.TypedValue { BoolValue = true },
+            TimeoutMs = 5000,
+            PollIntervalMs = 100,
+            Items =
+            {
+                new CodeFirst.WriteItem
+                {
+                    Tag = "Motor.Speed",
+                    Value = new CodeFirst.TypedValue { DoubleValue = 50.0 }
+                }
+            }
+        };
+
+        var ms = new MemoryStream();
+        Serializer.Serialize(ms, codeFirst);
+        var protoMsg = ProtoGenerated.WriteBatchAndWaitRequest.Parser.ParseFrom(ms.ToArray());
+
+        protoMsg.FlagTag.Should().Be("Motor.Done");
+        protoMsg.FlagValue.BoolValue.Should().BeTrue();
+        protoMsg.TimeoutMs.Should().Be(5000);
+        protoMsg.PollIntervalMs.Should().Be(100);
+        protoMsg.Items.Should().HaveCount(1);
+        protoMsg.Items[0].Tag.Should().Be("Motor.Speed");
+        protoMsg.Items[0].Value.DoubleValue.Should().Be(50.0);
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Client.Tests/Domain/QualityExtensionsTests.cs

@@ -0,0 +1,29 @@
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Client.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Tests.Domain;
+
+public class QualityExtensionsTests
+{
+    [Theory]
+    [InlineData(Quality.Good, true)]
+    [InlineData(Quality.Good_LocalOverride, true)]
+    [InlineData(Quality.Uncertain, false)]
+    [InlineData(Quality.Bad, false)]
+    public void IsGood(Quality q, bool expected) => q.IsGood().Should().Be(expected);
+
+    [Theory]
+    [InlineData(Quality.Uncertain, true)]
+    [InlineData(Quality.Uncertain_LastUsable, true)]
+    [InlineData(Quality.Good, false)]
+    [InlineData(Quality.Bad, false)]
+    public void IsUncertain(Quality q, bool expected) => q.IsUncertain().Should().Be(expected);
+
+    [Theory]
+    [InlineData(Quality.Bad, true)]
+    [InlineData(Quality.Bad_CommFailure, true)]
+    [InlineData(Quality.Good, false)]
+    [InlineData(Quality.Uncertain, false)]
+    public void IsBad(Quality q, bool expected) => q.IsBad().Should().Be(expected);
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Client.Tests/Domain/ScadaContractsTests.cs

@@ -0,0 +1,134 @@
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Client.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Tests.Domain;
+
+public class ScadaContractsTests
+{
+    [Fact]
+    public void TypedValue_GetValueCase_Bool()
+    {
+        var tv = new TypedValue { BoolValue = true };
+        tv.GetValueCase().Should().Be(TypedValueCase.BoolValue);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_Int32()
+    {
+        var tv = new TypedValue { Int32Value = 42 };
+        tv.GetValueCase().Should().Be(TypedValueCase.Int32Value);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_Double()
+    {
+        var tv = new TypedValue { DoubleValue = 3.14 };
+        tv.GetValueCase().Should().Be(TypedValueCase.DoubleValue);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_String()
+    {
+        var tv = new TypedValue { StringValue = "hello" };
+        tv.GetValueCase().Should().Be(TypedValueCase.StringValue);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_None_WhenDefault()
+    {
+        var tv = new TypedValue();
+        tv.GetValueCase().Should().Be(TypedValueCase.None);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_Datetime()
+    {
+        var tv = new TypedValue { DatetimeValue = DateTime.UtcNow.Ticks };
+        tv.GetValueCase().Should().Be(TypedValueCase.DatetimeValue);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_BytesValue()
+    {
+        var tv = new TypedValue { BytesValue = new byte[] { 1, 2, 3 } };
+        tv.GetValueCase().Should().Be(TypedValueCase.BytesValue);
+    }
+
+    [Fact]
+    public void TypedValue_GetValueCase_ArrayValue()
+    {
+        var tv = new TypedValue
+        {
+            ArrayValue = new ArrayValue
+            {
+                FloatValues = new FloatArray { Values = { 1.0f, 2.0f } }
+            }
+        };
+        tv.GetValueCase().Should().Be(TypedValueCase.ArrayValue);
+    }
+
+    [Fact]
+    public void QualityCode_IsGood()
+    {
+        var qc = new QualityCode { StatusCode = 0x00000000, SymbolicName = "Good" };
+        qc.IsGood.Should().BeTrue();
+        qc.IsBad.Should().BeFalse();
+        qc.IsUncertain.Should().BeFalse();
+    }
+
+    [Fact]
+    public void QualityCode_IsBad()
+    {
+        var qc = new QualityCode { StatusCode = 0x80000000, SymbolicName = "Bad" };
+        qc.IsGood.Should().BeFalse();
+        qc.IsBad.Should().BeTrue();
+        qc.IsUncertain.Should().BeFalse();
+    }
+
+    [Fact]
+    public void QualityCode_IsUncertain()
+    {
+        var qc = new QualityCode { StatusCode = 0x40900000, SymbolicName = "UncertainLastUsableValue" };
+        qc.IsGood.Should().BeFalse();
+        qc.IsBad.Should().BeFalse();
+        qc.IsUncertain.Should().BeTrue();
+    }
+
+    [Fact]
+    public void VtqMessage_DefaultProperties()
+    {
+        var vtq = new VtqMessage();
+        vtq.Tag.Should().BeEmpty();
+        vtq.Value.Should().BeNull();
+        vtq.TimestampUtcTicks.Should().Be(0);
+        vtq.Quality.Should().BeNull();
+    }
+
+    [Fact]
+    public void WriteBatchAndWaitRequest_FlagValue_IsTypedValue()
+    {
+        var req = new WriteBatchAndWaitRequest
+        {
+            SessionId = "abc",
+            FlagTag = "Motor.Done",
+            FlagValue = new TypedValue { BoolValue = true },
+            TimeoutMs = 5000,
+            PollIntervalMs = 100
+        };
+        req.FlagValue.Should().NotBeNull();
+        req.FlagValue!.GetValueCase().Should().Be(TypedValueCase.BoolValue);
+    }
+
+    [Fact]
+    public void WriteItem_Value_IsTypedValue()
+    {
+        var item = new WriteItem
+        {
+            Tag = "Motor.Speed",
+            Value = new TypedValue { DoubleValue = 42.5 }
+        };
+        item.Value.Should().NotBeNull();
+        item.Value!.GetValueCase().Should().Be(TypedValueCase.DoubleValue);
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Client.Tests/Domain/VtqTests.cs

@@ -0,0 +1,33 @@
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Client.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Tests.Domain;
+
+public class VtqTests
+{
+    [Fact]
+    public void Good_FactoryMethod()
+    {
+        var vtq = Vtq.Good(42.0);
+        vtq.Value.Should().Be(42.0);
+        vtq.Quality.Should().Be(Quality.Good);
+        vtq.Timestamp.Kind.Should().Be(DateTimeKind.Utc);
+    }
+
+    [Fact]
+    public void Bad_FactoryMethod()
+    {
+        var vtq = Vtq.Bad();
+        vtq.Value.Should().BeNull();
+        vtq.Quality.Should().Be(Quality.Bad);
+    }
+
+    [Fact]
+    public void Uncertain_FactoryMethod()
+    {
+        var vtq = Vtq.Uncertain("stale");
+        vtq.Value.Should().Be("stale");
+        vtq.Quality.Should().Be(Quality.Uncertain);
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Client.Tests/ZB.MOM.WW.LmxProxy.Client.Tests.csproj

@@ -0,0 +1,36 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <IsPackable>false</IsPackable>
+    <RootNamespace>ZB.MOM.WW.LmxProxy.Client.Tests</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="FluentAssertions" Version="7.2.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.29.3" />
+    <PackageReference Include="Grpc.Tools" Version="2.68.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\ZB.MOM.WW.LmxProxy.Client\ZB.MOM.WW.LmxProxy.Client.csproj" />
+  </ItemGroup>
+
+  <!-- Proto file for cross-stack serialization tests (Host proto → Client code-first) -->
+  <ItemGroup>
+    <Protobuf Include="..\..\src\ZB.MOM.WW.LmxProxy.Host\Grpc\Protos\scada.proto" GrpcServices="None" Link="Protos\scada.proto" />
+  </ItemGroup>
+
+</Project>

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Host.Tests/Domain/QualityCodeMapperTests.cs

@@ -0,0 +1,87 @@
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Host.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Tests.Domain
+{
+    public class QualityCodeMapperTests
+    {
+        [Theory]
+        [InlineData(Quality.Good, 0x00000000u, "Good")]
+        [InlineData(Quality.Good_LocalOverride, 0x00D80000u, "GoodLocalOverride")]
+        [InlineData(Quality.Bad, 0x80000000u, "Bad")]
+        [InlineData(Quality.Bad_ConfigError, 0x80040000u, "BadConfigurationError")]
+        [InlineData(Quality.Bad_NotConnected, 0x808A0000u, "BadNotConnected")]
+        [InlineData(Quality.Bad_DeviceFailure, 0x806B0000u, "BadDeviceFailure")]
+        [InlineData(Quality.Bad_SensorFailure, 0x806D0000u, "BadSensorFailure")]
+        [InlineData(Quality.Bad_CommFailure, 0x80050000u, "BadCommunicationFailure")]
+        [InlineData(Quality.Bad_OutOfService, 0x808F0000u, "BadOutOfService")]
+        [InlineData(Quality.Bad_WaitingForInitialData, 0x80320000u, "BadWaitingForInitialData")]
+        [InlineData(Quality.Uncertain_LastUsable, 0x40900000u, "UncertainLastUsableValue")]
+        [InlineData(Quality.Uncertain_SensorNotAcc, 0x42390000u, "UncertainSensorNotAccurate")]
+        [InlineData(Quality.Uncertain_EuExceeded, 0x40540000u, "UncertainEngineeringUnitsExceeded")]
+        [InlineData(Quality.Uncertain_SubNormal, 0x40580000u, "UncertainSubNormal")]
+        public void ToQualityCode_MapsCorrectly(Quality quality, uint expectedStatusCode, string expectedName)
+        {
+            var qc = QualityCodeMapper.ToQualityCode(quality);
+            qc.StatusCode.Should().Be(expectedStatusCode);
+            qc.SymbolicName.Should().Be(expectedName);
+        }
+
+        [Theory]
+        [InlineData(0x00000000u, Quality.Good)]
+        [InlineData(0x80000000u, Quality.Bad)]
+        [InlineData(0x80040000u, Quality.Bad_ConfigError)]
+        [InlineData(0x806D0000u, Quality.Bad_SensorFailure)]
+        [InlineData(0x40900000u, Quality.Uncertain_LastUsable)]
+        public void FromStatusCode_MapsCorrectly(uint statusCode, Quality expectedQuality)
+        {
+            QualityCodeMapper.FromStatusCode(statusCode).Should().Be(expectedQuality);
+        }
+
+        [Fact]
+        public void FromStatusCode_UnknownGoodCode_FallsBackToGood()
+        {
+            QualityCodeMapper.FromStatusCode(0x00FF0000).Should().Be(Quality.Good);
+        }
+
+        [Fact]
+        public void FromStatusCode_UnknownBadCode_FallsBackToBad()
+        {
+            QualityCodeMapper.FromStatusCode(0x80FF0000).Should().Be(Quality.Bad);
+        }
+
+        [Fact]
+        public void FromStatusCode_UnknownUncertainCode_FallsBackToUncertain()
+        {
+            QualityCodeMapper.FromStatusCode(0x40FF0000).Should().Be(Quality.Uncertain);
+        }
+
+        [Theory]
+        [InlineData(0x00000000u, "Good")]
+        [InlineData(0x80000000u, "Bad")]
+        [InlineData(0x806D0000u, "BadSensorFailure")]
+        [InlineData(0x40900000u, "UncertainLastUsableValue")]
+        [InlineData(0x80FF0000u, "Bad")]  // unknown bad code falls back
+        public void GetSymbolicName_ReturnsCorrectName(uint statusCode, string expectedName)
+        {
+            QualityCodeMapper.GetSymbolicName(statusCode).Should().Be(expectedName);
+        }
+
+        [Fact]
+        public void FactoryMethods_ReturnCorrectCodes()
+        {
+            QualityCodeMapper.Good().StatusCode.Should().Be(0x00000000u);
+            QualityCodeMapper.Bad().StatusCode.Should().Be(0x80000000u);
+            QualityCodeMapper.BadConfigurationError().StatusCode.Should().Be(0x80040000u);
+            QualityCodeMapper.BadCommunicationFailure().StatusCode.Should().Be(0x80050000u);
+            QualityCodeMapper.BadNotConnected().StatusCode.Should().Be(0x808A0000u);
+            QualityCodeMapper.BadDeviceFailure().StatusCode.Should().Be(0x806B0000u);
+            QualityCodeMapper.BadSensorFailure().StatusCode.Should().Be(0x806D0000u);
+            QualityCodeMapper.BadOutOfService().StatusCode.Should().Be(0x808F0000u);
+            QualityCodeMapper.BadWaitingForInitialData().StatusCode.Should().Be(0x80320000u);
+            QualityCodeMapper.GoodLocalOverride().StatusCode.Should().Be(0x00D80000u);
+            QualityCodeMapper.UncertainLastUsableValue().StatusCode.Should().Be(0x40900000u);
+        }
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Host.Tests/Domain/QualityExtensionsTests.cs

@@ -0,0 +1,39 @@
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Host.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Tests.Domain
+{
+    public class QualityExtensionsTests
+    {
+        [Theory]
+        [InlineData(Quality.Good, true)]
+        [InlineData(Quality.Good_LocalOverride, true)]
+        [InlineData(Quality.Uncertain, false)]
+        [InlineData(Quality.Bad, false)]
+        public void IsGood(Quality q, bool expected)
+        {
+            q.IsGood().Should().Be(expected);
+        }
+
+        [Theory]
+        [InlineData(Quality.Uncertain, true)]
+        [InlineData(Quality.Uncertain_LastUsable, true)]
+        [InlineData(Quality.Good, false)]
+        [InlineData(Quality.Bad, false)]
+        public void IsUncertain(Quality q, bool expected)
+        {
+            q.IsUncertain().Should().Be(expected);
+        }
+
+        [Theory]
+        [InlineData(Quality.Bad, true)]
+        [InlineData(Quality.Bad_CommFailure, true)]
+        [InlineData(Quality.Good, false)]
+        [InlineData(Quality.Uncertain, false)]
+        public void IsBad(Quality q, bool expected)
+        {
+            q.IsBad().Should().Be(expected);
+        }
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Host.Tests/Domain/TypedValueConverterTests.cs

@@ -0,0 +1,196 @@
+using System;
+using FluentAssertions;
+using Xunit;
+using ZB.MOM.WW.LmxProxy.Host.Domain;
+
+namespace ZB.MOM.WW.LmxProxy.Host.Tests.Domain
+{
+    public class TypedValueConverterTests
+    {
+        [Fact]
+        public void Null_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(null);
+            tv.Should().BeNull();
+            TypedValueConverter.FromTypedValue(null).Should().BeNull();
+        }
+
+        [Fact]
+        public void DBNull_MapsToNull()
+        {
+            var tv = TypedValueConverter.ToTypedValue(DBNull.Value);
+            tv.Should().BeNull();
+        }
+
+        [Fact]
+        public void Bool_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(true);
+            tv.Should().NotBeNull();
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.BoolValue);
+            tv.BoolValue.Should().BeTrue();
+            TypedValueConverter.FromTypedValue(tv).Should().Be(true);
+
+            var tvFalse = TypedValueConverter.ToTypedValue(false);
+            tvFalse!.BoolValue.Should().BeFalse();
+            TypedValueConverter.FromTypedValue(tvFalse).Should().Be(false);
+        }
+
+        [Fact]
+        public void Short_WidensToInt32()
+        {
+            var tv = TypedValueConverter.ToTypedValue((short)42);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int32Value);
+            tv.Int32Value.Should().Be(42);
+            TypedValueConverter.FromTypedValue(tv).Should().Be(42);
+        }
+
+        [Fact]
+        public void Int_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(int.MaxValue);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int32Value);
+            tv.Int32Value.Should().Be(int.MaxValue);
+            TypedValueConverter.FromTypedValue(tv).Should().Be(int.MaxValue);
+        }
+
+        [Fact]
+        public void Long_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(long.MaxValue);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int64Value);
+            tv.Int64Value.Should().Be(long.MaxValue);
+            TypedValueConverter.FromTypedValue(tv).Should().Be(long.MaxValue);
+        }
+
+        [Fact]
+        public void UShort_WidensToInt32()
+        {
+            var tv = TypedValueConverter.ToTypedValue((ushort)65535);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int32Value);
+            tv.Int32Value.Should().Be(65535);
+        }
+
+        [Fact]
+        public void UInt_WidensToInt64()
+        {
+            var tv = TypedValueConverter.ToTypedValue(uint.MaxValue);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int64Value);
+            tv.Int64Value.Should().Be(uint.MaxValue);
+        }
+
+        [Fact]
+        public void ULong_MapsToInt64()
+        {
+            var tv = TypedValueConverter.ToTypedValue((ulong)12345678);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.Int64Value);
+            tv.Int64Value.Should().Be(12345678);
+        }
+
+        [Fact]
+        public void Float_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(3.14159f);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.FloatValue);
+            tv.FloatValue.Should().Be(3.14159f);
+            TypedValueConverter.FromTypedValue(tv).Should().Be(3.14159f);
+        }
+
+        [Fact]
+        public void Double_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue(2.718281828459045);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.DoubleValue);
+            tv.DoubleValue.Should().Be(2.718281828459045);
+            TypedValueConverter.FromTypedValue(tv).Should().Be(2.718281828459045);
+        }
+
+        [Fact]
+        public void String_RoundTrips()
+        {
+            var tv = TypedValueConverter.ToTypedValue("Hello World");
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.StringValue);
+            tv.StringValue.Should().Be("Hello World");
+            TypedValueConverter.FromTypedValue(tv).Should().Be("Hello World");
+        }
+
+        [Fact]
+        public void DateTime_RoundTrips_AsUtcTicks()
+        {
+            var dt = new DateTime(2026, 3, 21, 12, 0, 0, DateTimeKind.Utc);
+            var tv = TypedValueConverter.ToTypedValue(dt);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.DatetimeValue);
+            tv.DatetimeValue.Should().Be(dt.Ticks);
+            var result = (DateTime)TypedValueConverter.FromTypedValue(tv)!;
+            result.Kind.Should().Be(DateTimeKind.Utc);
+            result.Ticks.Should().Be(dt.Ticks);
+        }
+
+        [Fact]
+        public void ByteArray_RoundTrips()
+        {
+            var bytes = new byte[] { 0x00, 0xFF, 0x42 };
+            var tv = TypedValueConverter.ToTypedValue(bytes);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.BytesValue);
+            var result = (byte[])TypedValueConverter.FromTypedValue(tv)!;
+            result.Should().BeEquivalentTo(bytes);
+        }
+
+        [Fact]
+        public void Decimal_MapsToDouble()
+        {
+            var tv = TypedValueConverter.ToTypedValue(123.456m);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.DoubleValue);
+            tv.DoubleValue.Should().BeApproximately(123.456, 0.001);
+        }
+
+        [Fact]
+        public void FloatArray_RoundTrips()
+        {
+            var arr = new float[] { 1.0f, 2.0f, 3.0f };
+            var tv = TypedValueConverter.ToTypedValue(arr);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.ArrayValue);
+            var result = (float[])TypedValueConverter.FromTypedValue(tv)!;
+            result.Should().BeEquivalentTo(arr);
+        }
+
+        [Fact]
+        public void IntArray_RoundTrips()
+        {
+            var arr = new int[] { 10, 20, 30 };
+            var tv = TypedValueConverter.ToTypedValue(arr);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.ArrayValue);
+            var result = (int[])TypedValueConverter.FromTypedValue(tv)!;
+            result.Should().BeEquivalentTo(arr);
+        }
+
+        [Fact]
+        public void StringArray_RoundTrips()
+        {
+            var arr = new string[] { "a", "b", "c" };
+            var tv = TypedValueConverter.ToTypedValue(arr);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.ArrayValue);
+            var result = (string[])TypedValueConverter.FromTypedValue(tv)!;
+            result.Should().BeEquivalentTo(arr);
+        }
+
+        [Fact]
+        public void DoubleArray_RoundTrips()
+        {
+            var arr = new double[] { 1.1, 2.2, 3.3 };
+            var tv = TypedValueConverter.ToTypedValue(arr);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.ArrayValue);
+            var result = (double[])TypedValueConverter.FromTypedValue(tv)!;
+            result.Should().BeEquivalentTo(arr);
+        }
+
+        [Fact]
+        public void UnrecognizedType_FallsBackToString()
+        {
+            var guid = Guid.NewGuid();
+            var tv = TypedValueConverter.ToTypedValue(guid);
+            tv!.ValueCase.Should().Be(Scada.TypedValue.ValueOneofCase.StringValue);
+            tv.StringValue.Should().Be(guid.ToString());
+        }
+    }
+}

lmxproxy/tests/ZB.MOM.WW.LmxProxy.Host.Tests/ZB.MOM.WW.LmxProxy.Host.Tests.csproj

@@ -0,0 +1,28 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net48</TargetFramework>
+    <LangVersion>9.0</LangVersion>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+    <RootNamespace>ZB.MOM.WW.LmxProxy.Host.Tests</RootNamespace>
+    <PlatformTarget>x86</PlatformTarget>
+    <Platforms>x86</Platforms>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="FluentAssertions" Version="6.12.2" />
+    <PackageReference Include="Google.Protobuf" Version="3.29.3" />
+  </ItemGroup>
+
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