feat(config): DraftValidator rule + DraftSnapshot.VirtualTags for Tag/VirtualTag NodeId collisions

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/Validation/DraftSnapshot.cs

@@ -39,6 +39,10 @@ public sealed class DraftSnapshot
     public IReadOnlyList<Equipment> Equipment { get; init; } = [];
     /// <summary>Gets the list of tags.</summary>
     public IReadOnlyList<Tag> Tags { get; init; } = [];
+
+    /// <summary>Equipment-bound VirtualTags (script-derived signals). Shares the equipment NodeId space
+    /// with Tags; the collision rule checks both.</summary>
+    public IReadOnlyList<VirtualTag> VirtualTags { get; init; } = [];
     /// <summary>Gets the list of poll groups.</summary>
     public IReadOnlyList<PollGroup> PollGroups { get; init; } = [];
 

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/Validation/DraftValidator.cs

@@ -32,10 +32,34 @@ public static class DraftValidator
         ValidateReservationPreflight(draft, errors);
         ValidateEquipmentIdDerivation(draft, errors);
         ValidateDriverNamespaceCompatibility(draft, errors);
+        ValidateNoEquipmentSignalNameCollision(draft, errors);
 
         return errors;
     }
 
+    private static void ValidateNoEquipmentSignalNameCollision(DraftSnapshot draft, List<ValidationError> errors)
+    {
+        // Materialiser NodeId key: "{EquipmentId}[/{FolderPath}]/{Name}". Tag (EquipmentId != null) and
+        // VirtualTag share this space with no DB cross-table uniqueness, so the same key from both collides.
+        static string Key(string eq, string? folder, string name) =>
+            string.IsNullOrWhiteSpace(folder) ? $"{eq}/{name}" : $"{eq}/{folder}/{name}";
+
+        var signals = draft.Tags
+            .Where(t => t.EquipmentId is not null)
+            .Select(t => (Key: Key(t.EquipmentId!, t.FolderPath, t.Name), Eq: t.EquipmentId!, t.Name))
+            .Concat(draft.VirtualTags
+                .Select(v => (Key: Key(v.EquipmentId, null, v.Name), Eq: v.EquipmentId, v.Name)));
+
+        foreach (var g in signals.GroupBy(s => s.Key, StringComparer.Ordinal).Where(g => g.Count() > 1))
+        {
+            var f = g.First();
+            errors.Add(new("EquipmentSignalNameCollision",
+                $"{g.Count()} signals collide on OPC UA NodeId '{g.Key}' (equipment '{f.Eq}', name '{f.Name}'); " +
+                "a Name must be unique across Tag and VirtualTag within an equipment+folder",
+                f.Eq));
+        }
+    }
+
     private static bool IsValidSegment(string? s) =>
         s is not null && (UnsSegment.IsMatch(s) || s == UnsDefaultSegment);
 

tests/Core/ZB.MOM.WW.OtOpcUa.Configuration.Tests/DraftValidatorTests.cs

@@ -186,6 +186,76 @@ public sealed class DraftValidatorTests
         errors.ShouldContain(e => e.Code == "UnsSegmentInvalid");
     }
 
+    // ------------------------------------------------------------------------------------
+    // ValidateNoEquipmentSignalNameCollision — Tag/VirtualTag NodeId collision
+    // ------------------------------------------------------------------------------------
+
+    /// <summary>Verifies that an equipment-bound Tag and a VirtualTag sharing the same
+    /// equipment+name collide on a single OPC UA NodeId.</summary>
+    [Fact]
+    public void Tag_and_VirtualTag_same_equipment_and_name_collide()
+    {
+        var draft = new DraftSnapshot
+        {
+            GenerationId = 1, ClusterId = "c",
+            Tags = [BuildTag(equipmentId: "eq-1", name: "speed", folderPath: null)],
+            VirtualTags = [BuildVirtualTag(equipmentId: "eq-1", name: "speed")],
+        };
+
+        DraftValidator.Validate(draft).ShouldContain(e => e.Code == "EquipmentSignalNameCollision");
+    }
+
+    /// <summary>Verifies that a Tag in a sub-folder does not collide with a VirtualTag at the
+    /// equipment root even when the names match — the NodeId keys differ.</summary>
+    [Fact]
+    public void Same_name_different_folder_does_not_collide()
+    {
+        var draft = new DraftSnapshot
+        {
+            GenerationId = 1, ClusterId = "c",
+            Tags = [BuildTag(equipmentId: "eq-1", name: "speed", folderPath: "metrics")],
+            VirtualTags = [BuildVirtualTag(equipmentId: "eq-1", name: "speed")],
+        };
+
+        DraftValidator.Validate(draft).ShouldNotContain(e => e.Code == "EquipmentSignalNameCollision");
+    }
+
+    /// <summary>Verifies that a SystemPlatform Tag (EquipmentId == null) is excluded from the
+    /// equipment-signal node space and so never collides with an equipment VirtualTag.</summary>
+    [Fact]
+    public void SystemPlatform_tag_sharing_name_with_equipment_vtag_excluded()
+    {
+        var draft = new DraftSnapshot
+        {
+            GenerationId = 1, ClusterId = "c",
+            Tags = [BuildTag(equipmentId: null, name: "speed", folderPath: null)],
+            VirtualTags = [BuildVirtualTag(equipmentId: "eq-1", name: "speed")],
+        };
+
+        DraftValidator.Validate(draft).ShouldNotContain(e => e.Code == "EquipmentSignalNameCollision");
+    }
+
+    private static Tag BuildTag(string? equipmentId, string name, string? folderPath) => new()
+    {
+        TagId = $"tag-{name}",
+        DriverInstanceId = "d",
+        EquipmentId = equipmentId,
+        Name = name,
+        FolderPath = folderPath,
+        DataType = "Float",
+        AccessLevel = TagAccessLevel.Read,
+        TagConfig = "{}",
+    };
+
+    private static VirtualTag BuildVirtualTag(string equipmentId, string name) => new()
+    {
+        VirtualTagId = $"vtag-{name}",
+        EquipmentId = equipmentId,
+        Name = name,
+        DataType = "Float",
+        ScriptId = "s-1",
+    };
+
     // ------------------------------------------------------------------------------------
     // Phase 6.3 task #148 part 2 — ValidateClusterTopology
     // ------------------------------------------------------------------------------------