;;;; cl-scopes/csys - concurrent cybernetic communication systems

(defpackage :scopes/csys
  (:use :common-lisp)
  (:local-nicknames (:actor :scopes/core/actor)
                    (:config :scopes/config)
                    (:message :scopes/core/message)
                    (:shape :scopes/shape)
                    (:util :scopes/util)
                    (:alx :alexandria))
  (:export #:scope #:environ
           #:send #:send-message
           #:neuron #:synapse #:std-proc #:update
           #:handle-action))

(in-package :scopes/csys)

;;;; scope: information a neuron has access to

(defclass scope ()
  ((value :reader value :initarg :value :initform 0)
   (stage :reader stage :initform :initial)
   (syns :reader syns :initform nil)
   (program :reader program :initarg :program :initform nil)
   (actions :reader actions :initarg :actions :initform nil)
   (environ :reader environ :initarg :environ)))

(defun scope (&optional (program #'std-proc) &rest args)
  (apply #'make-instance 'scope :program program args))

;;;; neurons (= async tasks) and synapses (= connections)

(defun neuron (scope)
  (actor:create 
    (lambda (msg) (funcall msg scope))))

(defun synapse (rcvr &optional (op #'identity))
  (lambda (msg)
    (actor:send rcvr (funcall op msg))))

(defun update (scope)
  (actor:become 
    (lambda (msg) (funcall msg scope))))

(defun std-proc (msg scope)
  ;(util:lgi msg state syns env)
  (destructuring-bind (nmsg nscope) 
        (handle-action msg scope :default #'remember)
    (forward nmsg (syns nscope))
    (update nscope)))


;;;; effector procs for pseudo-neurons embedded in environment

(defun do-log (msg scope)
  (util:lgi msg))

;;;; helper / utility funtions

(defun forward (msg syns)
  (dolist (s syns) 
    (funcall s msg)))

(defun handle-action (msg scope &key (default #'no-op))
  (let* ((key (message:action-key msg))
         ;(act (select-action msg state default))
         (act (gethash key (actions scope) default)))
    (funcall act msg scope)))

;;;; predefined neuron actions

(defun no-op (msg scope)
  (list msg scope))

(defun remember (msg scope)
  ;(list msg (make-neuron-state (shape:data msg) syns))
  (list msg (shape:data msg) syns))