;; next/genesis/projections/define-registry.sx
;;
;; The meta-projection: folds Create{Define*{...}} activities into
;; the kernel registry. Resolves the chicken-and-egg circle —
;; bootstrap.erl populates the registry directly at startup from
;; the genesis bundle, and from then on define-registry's fold
;; keeps it current as new Define* activities arrive. Per design §5.

(DefineProjection
  :name "define-registry"
  :doc "Maps {kind, name} -> definition entry. Folded from\n        Create{DefineActivity|DefineObject|DefineProjection|\n        DefineValidator|DefineCodec|DefineSigSuite|...}. Kind is\n        derived from the inner :object :type tag."
  :initial-state {}
  :fold (fn
    (state act)
    (let
      ((obj (-> act :object)) (otype (-> act :object :type)))
      (cond
        (= (-> act :type) "Create")
        (cond
          (= otype "DefineActivity")
          (assoc-in state (list :activity-types (-> obj :name)) obj)
          (= otype "DefineObject")
          (assoc-in state (list :object-types (-> obj :name)) obj)
          (= otype "DefineProjection")
          (assoc-in state (list :projections (-> obj :name)) obj)
          (= otype "DefineValidator")
          (assoc-in state (list :validators (-> obj :name)) obj)
          (= otype "DefineCodec")
          (assoc-in state (list :codecs (-> obj :name)) obj)
          (= otype "DefineSigSuite")
          (assoc-in state (list :sig-suites (-> obj :name)) obj)
          :else state)
        :else state))))