Add D&D scene description validation

internal/modules/dnd/validate/scenedescriptions/shape/validator.go

@@ -0,0 +1,112 @@
+// Package shape validates required D&D scene description fields.
+package shape
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
+	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd"
+	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/shared/diagnostics"
+)
+
+const (
+	Key        = "extract/dnd/scene-descriptions/shape"
+	ReasonCode = "invalid_scene_description_shape"
+	policy     = "dnd.scene_descriptions.validator.shape.v1"
+)
+
+type Options struct{}
+type Validator struct{}
+
+var _ contracts.TypedValidator[dnd.SceneDescriptionList] = (*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.SceneDescriptionList]) (contracts.ValidationResult, error) {
+	if err := ValidateForStage(req.Value, req.Stage); err != nil {
+		return contracts.ValidationResult{Approved: false, ReasonCode: ReasonCode, Message: err.Error()}, nil
+	}
+	return contracts.ValidationResult{Approved: true}, nil
+}
+
+func Validate(value dnd.SceneDescriptionList) error { return validate(value, false) }
+
+func ValidateForStage(value dnd.SceneDescriptionList, stage string) error {
+	return validate(value, stage == string(pipeline.StageExtract))
+}
+
+func validate(value dnd.SceneDescriptionList, exactlyOne bool) error {
+	issues := make([]string, 0)
+	if value.Scenes == nil {
+		issues = append(issues, "scenes must be present")
+	} else if len(value.Scenes) == 0 {
+		issues = append(issues, "scenes must not be empty")
+	} else if exactlyOne && len(value.Scenes) != 1 {
+		issues = append(issues, "extraction must contain exactly one scene")
+	}
+	for index, scene := range value.Scenes {
+		prefix := fmt.Sprintf("scenes[%d]", index)
+		if strings.TrimSpace(scene.ID) == "" || scene.ID != strings.TrimSpace(scene.ID) {
+			issues = append(issues, prefix+".id must be non-empty and trimmed")
+		}
+		if !ValidKind(scene.Kind) {
+			issues = append(issues, prefix+".kind is unsupported: "+diagnostics.Quote(string(scene.Kind)))
+		}
+		if strings.TrimSpace(scene.Title) == "" || scene.Title != strings.TrimSpace(scene.Title) {
+			issues = append(issues, prefix+".title must be non-empty and trimmed")
+		}
+		if strings.TrimSpace(scene.Summary) == "" || scene.Summary != strings.TrimSpace(scene.Summary) {
+			issues = append(issues, prefix+".summary must be non-empty and trimmed")
+		}
+		if strings.TrimSpace(scene.SourceRef.SourceID) == "" || scene.SourceRef.SourceID != strings.TrimSpace(scene.SourceRef.SourceID) || scene.SourceRef.StartUnitID <= 0 || scene.SourceRef.EndUnitID <= 0 {
+			issues = append(issues, prefix+".source_ref must have a trimmed source ID and positive unit IDs")
+		}
+	}
+	if len(issues) == 0 {
+		return nil
+	}
+	return fmt.Errorf("%s", diagnostics.Aggregate("invalid scene description shape", issues))
+}
+
+func ValidKind(value dnd.SceneKind) bool {
+	switch value {
+	case dnd.SceneKindCombat, dnd.SceneKindNarrative, dnd.SceneKindRecap, dnd.SceneKindMeta:
+		return true
+	default:
+		return false
+	}
+}
+
+func Spec() pipeline.ValidatorSpec {
+	return pipeline.ValidatorSpec{Key: Key, ExecutionClass: contracts.ExecutionClassDeterministic}
+}
+
+func Register(registry *pipeline.ValidatorRegistry) error {
+	return pipeline.RegisterTypedValidatorBuilder(registry, dnd.SceneDescriptionListKind, Spec(), validateOptions, func(request pipeline.BuildRequest) (contracts.TypedValidator[dnd.SceneDescriptionList], 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 }