Fix FAT TCS smart signal finding regression

Services/IoTesting/IoTestReferenceMatcher.cs

@@ -5,8 +5,9 @@ namespace ArIED61850Tester.Services.IoTesting;
 /// <summary>
 /// Conservative IEC 61850 reference matcher used by FAT binding. It understands
 /// equivalent MMS/SCL spellings (IED-prefixed domains, the DIGSI Application display
-/// wrapper, functional-constraint tokens inside MMS references, and verified Siemens
-/// functional-group/LN display folders) but never uses fuzzy text similarity.
+/// wrapper, functional-constraint tokens inside MMS references, verified Siemens
+/// functional-group/LN display folders, and exact unique object-leaf recovery for
+/// incomplete imported references) but never uses fuzzy text similarity.
 /// </summary>
 internal static class IoTestReferenceMatcher
 {
@@ -24,6 +25,7 @@ internal static class IoTestReferenceMatcher
     internal const int ExactScore = 100;
     internal const int CanonicalScore = 90;
     internal const int ContainerScore = 70;
+    internal const int PartialObjectScore = 60;
 
     internal static int Score(
         string? importedReference,
@@ -55,6 +57,20 @@ internal static int Score(
             }
         }
 
+        // Some customer FAT sheets contain a valid exact data-object name but have
+        // lost the LD/LN path, for example `.TCS1Fail`. Recover that case only by an
+        // exact IEC object-leaf boundary match. This deliberately scores below every
+        // fully attributable form; the caller still requires one unique best candidate,
+        // so duplicate leaves in different logical nodes remain ambiguous and blocked.
+        foreach (var expected in importedForms)
+        {
+            foreach (var observed in observedForms)
+            {
+                if (IsSafePartialObjectMatch(expected, observed))
+                    return PartialObjectScore;
+            }
+        }
+
         return 0;
     }
 
@@ -208,4 +224,75 @@ private static bool IsSafeImplicitLeafMatch(string expected, string observed)
         var suffix = observed[(expected.Length + 1)..];
         return SafeImplicitValueLeaves.Contains(suffix);
     }
+
+    private static bool IsSafePartialObjectMatch(string expected, string observed)
+    {
+        var expectedObject = ParsePartialImportedObject(expected);
+        if (expectedObject is null)
+            return false;
+
+        var observedObject = ParseObservedObject(observed);
+        if (observedObject is null ||
+            !expectedObject.ObjectName.Equals(observedObject.ObjectName, StringComparison.OrdinalIgnoreCase))
+        {
+            return false;
+        }
+
+        if (expectedObject.ValueSuffix.Length > 0)
+        {
+            return expectedObject.ValueSuffix.Equals(
+                observedObject.ValueSuffix,
+                StringComparison.OrdinalIgnoreCase);
+        }
+
+        return observedObject.ValueSuffix.Length == 0 ||
+               SafeImplicitValueLeaves.Contains(observedObject.ValueSuffix);
+    }
+
+    private static ObjectLeaf? ParsePartialImportedObject(string value)
+    {
+        var normalized = (value ?? string.Empty).Trim().TrimStart('.').TrimEnd('.');
+        if (normalized.Length == 0 || normalized.Contains('/'))
+            return null;
+
+        var stripped = StripSafeValueSuffix(normalized);
+        if (stripped.Base.Length == 0 || stripped.Base.Contains('.') || !IsIecIdentifier(stripped.Base))
+            return null;
+
+        return new ObjectLeaf(stripped.Base, stripped.Suffix);
+    }
+
+    private static ObjectLeaf? ParseObservedObject(string value)
+    {
+        var normalized = (value ?? string.Empty).Trim().Trim('.');
+        if (normalized.Length == 0)
+            return null;
+
+        var stripped = StripSafeValueSuffix(normalized);
+        var separator = Math.Max(stripped.Base.LastIndexOf('/'), stripped.Base.LastIndexOf('.'));
+        var objectName = separator >= 0 ? stripped.Base[(separator + 1)..] : stripped.Base;
+        if (!IsIecIdentifier(objectName))
+            return null;
+
+        return new ObjectLeaf(objectName, stripped.Suffix);
+    }
+
+    private static (string Base, string Suffix) StripSafeValueSuffix(string value)
+    {
+        foreach (var leaf in SafeImplicitValueLeaves.OrderByDescending(item => item.Length))
+        {
+            var suffix = "." + leaf;
+            if (!value.EndsWith(suffix, StringComparison.OrdinalIgnoreCase))
+                continue;
+
+            return (value[..^suffix.Length], leaf.ToLowerInvariant());
+        }
+
+        return (value, string.Empty);
+    }
+
+    private static bool IsIecIdentifier(string value)
+        => Regex.IsMatch(value, @"^[A-Za-z_][A-Za-z0-9_]*$", RegexOptions.CultureInvariant);
+
+    private sealed record ObjectLeaf(string ObjectName, string ValueSuffix);
 }

tests/ARSAS.Tests/IoTestLiveBindingServiceTests.cs

@@ -62,6 +62,54 @@ public void ApplicationFolderHierarchy_IsNormalizedToLiveLnPrefix()
         Assert.Contains("verified functional-group/LN boundary", project.Ieds[0].TestPoints[0].LiveBindingReason, StringComparison.OrdinalIgnoreCase);
     }
 
+    [Fact]
+    public void PartialTcsLeaf_IsBoundUniquelyToDiscoveredSignal()
+    {
+        var project = Project(".TCS1Fail");
+        var device = Device();
+        device.Signals.Add(new SignalDefinition
+        {
+            Name = "Trip coil monitoring 1",
+            ObjectReference = "AA1C1F03R4Application/ADDGGIO2$ST$TCS1Fail$stVal",
+            FunctionalConstraint = "ST"
+        });
+
+        var summary = _binding.Bind(project, new[] { device });
+
+        Assert.Equal(1, summary.SignalBoundCount);
+        Assert.Equal(0, summary.MissingSignalCount);
+        Assert.Equal(IoTestLiveBindingState.BoundNormalized, project.Ieds[0].TestPoints[0].LiveBindingState);
+        Assert.Equal(
+            "AA1C1F03R4Application/ADDGGIO2$ST$TCS1Fail$stVal",
+            project.Ieds[0].TestPoints[0].LiveSignalReference);
+    }
+
+    [Fact]
+    public void PartialTcsLeaf_DuplicateObjectsRemainBlocked()
+    {
+        var project = Project(".TCS1Fail");
+        var device = Device();
+        device.Signals.Add(new SignalDefinition
+        {
+            Name = "Trip coil monitoring 1 ADD",
+            ObjectReference = "AA1C1F03R4Application/ADDGGIO2$ST$TCS1Fail$stVal",
+            FunctionalConstraint = "ST"
+        });
+        device.Signals.Add(new SignalDefinition
+        {
+            Name = "Trip coil monitoring 1 ALT",
+            ObjectReference = "AA1C1F03R4Application/ALTGGIO3$ST$TCS1Fail$stVal",
+            FunctionalConstraint = "ST"
+        });
+
+        var summary = _binding.Bind(project, new[] { device });
+
+        Assert.Equal(0, summary.SignalBoundCount);
+        Assert.Equal(1, summary.MissingSignalCount);
+        Assert.Equal(IoTestLiveBindingState.SignalNotFound, project.Ieds[0].TestPoints[0].LiveBindingState);
+        Assert.Contains("more than one equally strong", project.Ieds[0].TestPoints[0].LiveBindingReason, StringComparison.OrdinalIgnoreCase);
+    }
+
     [Fact]
     public void ActiveLivePoint_PopulatesCurrentEvidencePreview()
     {

tests/ARSAS.Tests/IoTestSmartReferenceMatcherTests.cs

@@ -74,6 +74,55 @@ public void EqualSmartCandidates_RemainAmbiguousInsteadOfBeingGuessed()
         Assert.Empty(result.MissingPoints);
     }
 
+    [Fact]
+    public void PartialTcsLeafReferences_ResolveUniquelyWithoutFuzzyGuessing()
+    {
+        var ied = FieldIed(
+            FieldPoint("UCC-IEC-TCS1", ".TCS1Fail"),
+            FieldPoint("UCC-IEC-TCS2", ".TCS2Fail"));
+        var device = FieldDevice(
+            Signal("Trip coil monitoring 1", "AA1C1F13R4Application/ADDGGIO2$ST$TCS1Fail$stVal", "ST"),
+            Signal("Trip coil monitoring 2", "AA1C1F13R4Application/ADDGGIO2$ST$TCS2Fail$stVal", "ST"));
+
+        var result = _service.Resolve(ied, device);
+
+        Assert.True(result.Succeeded, result.Message);
+        Assert.Equal(2, result.Matches.Count);
+        Assert.Empty(result.MissingPoints);
+        Assert.Empty(result.AmbiguousPoints);
+        Assert.All(result.Matches, match => Assert.True(match.UsedNormalizedIedPrefix));
+    }
+
+    [Fact]
+    public void PartialLeafReference_RemainsAmbiguousWhenObjectOccursInTwoLogicalNodes()
+    {
+        var ied = FieldIed(FieldPoint("UCC-IEC-TCS1", ".TCS1Fail"));
+        var device = FieldDevice(
+            Signal("TCS from ADD", "AA1C1F13R4Application/ADDGGIO2$ST$TCS1Fail$stVal", "ST"),
+            Signal("TCS from alternate LN", "AA1C1F13R4Application/ALTGGIO3$ST$TCS1Fail$stVal", "ST"));
+
+        var result = _service.Resolve(ied, device);
+
+        Assert.False(result.Succeeded);
+        Assert.Empty(result.MissingPoints);
+        Assert.Single(result.AmbiguousPoints);
+    }
+
+    [Fact]
+    public void PartialLeafReference_DoesNotUseNearTextSimilarity()
+    {
+        var ied = FieldIed(FieldPoint("UCC-IEC-TCS1", ".TCS1Fail"));
+        var device = FieldDevice(
+            Signal("Different numbered failure", "AA1C1F13R4Application/ADDGGIO2$ST$TCS11Fail$stVal", "ST"),
+            Signal("Healthy state", "AA1C1F13R4Application/ADDGGIO2$ST$TCS1Healthy$stVal", "ST"));
+
+        var result = _service.Resolve(ied, device);
+
+        Assert.False(result.Succeeded);
+        Assert.Single(result.MissingPoints);
+        Assert.Empty(result.AmbiguousPoints);
+    }
+
     private static IoTestIedPlan Ied(params IoTestPointPlan[] points) => new()
     {
         IedName = "AA1C1F06R2",
@@ -82,6 +131,14 @@ public void EqualSmartCandidates_RemainAmbiguousInsteadOfBeingGuessed()
         TestPoints = points.ToList()
     };
 
+    private static IoTestIedPlan FieldIed(params IoTestPointPlan[] points) => new()
+    {
+        IedName = "AA1C1F13R4",
+        IpAddress = "192.168.81.17",
+        IedRole = "BCU - 6MD85",
+        TestPoints = points.ToList()
+    };
+
     private static IoTestPointPlan Point(string id, string reference, string fc, string logicalNode) => new()
     {
         TestPointId = id,
@@ -97,6 +154,23 @@ public void EqualSmartCandidates_RemainAmbiguousInsteadOfBeingGuessed()
         TestEnabled = true
     };
 
+    private static IoTestPointPlan FieldPoint(string id, string reference) => new()
+    {
+        TestPointId = id,
+        IedName = "AA1C1F13R4",
+        IpAddress = "192.168.81.17",
+        SignalName = id,
+        ObjectReference = reference,
+        LogicalDevice = "AA1C1F13R4Application",
+        LogicalNode = "-",
+        DataAttribute = "stVal",
+        FunctionalConstraint = "ST",
+        ExpectedOnText = "Trip",
+        ExpectedOffText = "Normal",
+        ImportReady = true,
+        TestEnabled = true
+    };
+
     private static Iec61850MonitorDevice Device(params SignalDefinition[] signals)
     {
         var device = new Iec61850MonitorDevice
@@ -110,6 +184,19 @@ private static Iec61850MonitorDevice Device(params SignalDefinition[] signals)
         return device;
     }
 
+    private static Iec61850MonitorDevice FieldDevice(params SignalDefinition[] signals)
+    {
+        var device = new Iec61850MonitorDevice
+        {
+            Name = "AA1C1F13R4",
+            SclIedName = "AA1C1F13R4",
+            IpAddress = "192.168.81.17",
+            Port = 102
+        };
+        device.Signals.AddRange(signals);
+        return device;
+    }
+
     private static SignalDefinition Signal(string name, string reference, string fc) => new()
     {
         Name = name,