Add NPC normalization and identity validation

internal/modules/dnd/validate/npcs/identity/validator.go

@@ -0,0 +1,84 @@
+// Package identity validates the stable identity invariants of D&D NPC lists.
+package identity
+
+import (
+	"context"
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
+	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd"
+	domainidentity "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/npcs/identity"
+	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/validate/npcs/diagnostics"
+	npcshape "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/validate/npcs/shape"
+)
+
+const (
+	Key        = "normalize/dnd/npcs/identity"
+	ReasonCode = "invalid_npc_identity"
+	policy     = domainidentity.Policy
+)
+
+type Options struct{}
+type Validator struct{}
+
+var _ contracts.TypedValidator[dnd.NPCList] = (*Validator)(nil)
+var _ pipeline.CheckpointFingerprintProvider = (*Validator)(nil)
+
+func New(Options) *Validator      { return &Validator{} }
+func (v *Validator) Name() string { return Key }
+
+func (v *Validator) ExecutionClass() contracts.ExecutionClass {
+	return contracts.ExecutionClassDeterministic
+}
+
+func (v *Validator) CheckpointFingerprints() []pipeline.CheckpointFingerprint {
+	return []pipeline.CheckpointFingerprint{{Name: "policy", Value: policy}}
+}
+
+func (v *Validator) Validate(_ context.Context, req contracts.TypedValidationRequest[dnd.NPCList]) (contracts.ValidationResult, error) {
+	if err := npcshape.Validate(req.Value); err != nil {
+		return contracts.ValidationResult{Approved: true}, nil
+	}
+	identityIssues := domainidentity.ValidateRegistry(req.Value.NPCs)
+	if len(identityIssues) == 0 {
+		return contracts.ValidationResult{Approved: true}, nil
+	}
+
+	issues := make([]string, len(identityIssues))
+	for index, issue := range identityIssues {
+		location := fmt.Sprintf("npcs[%d]", issue.RecordIndex)
+		if issue.AliasIndex >= 0 {
+			location += fmt.Sprintf(".aliases[%d]", issue.AliasIndex)
+		}
+		issues[index] = fmt.Sprintf("%s %s: %s", location, issue.Code, diagnostics.Quote(issue.Value))
+	}
+	return contracts.ValidationResult{
+		Approved:   false,
+		ReasonCode: ReasonCode,
+		Message:    diagnostics.Aggregate("invalid NPC identity", issues),
+	}, nil
+}
+
+func Spec() pipeline.ValidatorSpec {
+	return pipeline.ValidatorSpec{Key: Key, ExecutionClass: contracts.ExecutionClassDeterministic}
+}
+
+func Register(registry *pipeline.ValidatorRegistry) error {
+	return pipeline.RegisterTypedValidatorBuilder(registry, dnd.NPCListKind, Spec(), validateOptions, func(request pipeline.BuildRequest) (contracts.TypedValidator[dnd.NPCList], error) {
+		options, err := DecodeOptions(request.Options)
+		if err != nil {
+			return nil, err
+		}
+		return New(options), nil
+	})
+}
+
+func DecodeOptions(options map[string]any) (Options, error) {
+	if err := pipeline.RejectUnknownOptions(options); err != nil {
+		return Options{}, err
+	}
+	return Options{}, nil
+}
+
+func validateOptions(options map[string]any) error { _, err := DecodeOptions(options); return err }