Tighten NPC interaction validation and consistency

internal/modules/dnd/validate/npcinteractions/source_refs/validator.go

@@ -16,7 +16,7 @@ import (
 const (
 	Key        = "extract/dnd/npc-interactions/source_refs"
 	ReasonCode = "invalid_npc_interaction_source_refs"
-	policy     = "dnd.npc_interactions.validator.source_refs.v1"
+	policy     = "dnd.npc_interactions.validator.source_refs.v2"
 )
 
 type Options struct{}
@@ -35,6 +35,9 @@ func (v *Validator) CheckpointFingerprints() []pipeline.CheckpointFingerprint {
 }
 
 func (v *Validator) Validate(_ context.Context, req contracts.TypedValidationRequest[dnd.NPCInteractionList]) (contracts.ValidationResult, error) {
+	if req.Stage == string(pipeline.StageExtract) && req.Chunk == nil {
+		return contracts.ValidationResult{}, fmt.Errorf("NPC interaction source-reference validator requires the current extraction chunk")
+	}
 	if interactionshape.Validate(req.Value) != nil {
 		return contracts.ValidationResult{Approved: true}, nil
 	}
@@ -43,6 +46,13 @@ func (v *Validator) Validate(_ context.Context, req contracts.TypedValidationReq
 		for refIndex, ref := range interaction.SourceRefs {
 			if err := source.ValidateRef(req.Source, ref); err != nil {
 				issues = append(issues, fmt.Sprintf("interactions[%d].source_refs[%d]: %s", interactionIndex, refIndex, diagnostics.Truncate(err.Error())))
+				continue
+			}
+			if req.Stage == string(pipeline.StageExtract) && !chunkContainsRef(req.Chunk, ref) {
+				issues = append(issues, fmt.Sprintf(
+					"interactions[%d].source_refs[%d]: source reference is outside the current extraction chunk",
+					interactionIndex, refIndex,
+				))
 			}
 		}
 	}
@@ -56,6 +66,19 @@ func (v *Validator) Validate(_ context.Context, req contracts.TypedValidationReq
 	}, nil
 }
 
+func chunkContainsRef(chunk *source.Chunk, ref source.SourceRef) bool {
+	if chunk == nil || ref.SourceID != chunk.SourceID {
+		return false
+	}
+	startFound := false
+	endFound := false
+	for _, unit := range chunk.Units {
+		startFound = startFound || unit.ID == ref.StartUnitID
+		endFound = endFound || unit.ID == ref.EndUnitID
+	}
+	return startFound && endFound
+}
+
 func Spec() pipeline.ValidatorSpec {
 	return pipeline.ValidatorSpec{Key: Key, ExecutionClass: contracts.ExecutionClassDeterministic}
 }