(* Time-stamp: <modified the 19/05/2019 (at 21:43) by Erwan Jahier> *)

(** Process programmer API *)
type varT = It | Ft | Bt | Et of int | St | Nt | At of varT * int
type vars = (string * varT) list 

type value = I of int | F of float | B of bool  | E of int | S of string
           | N of int  (* neighbor canal number *)
           | A of value array
type local_env = string -> value 
type action = string (* label *)
    
type neighbor = {
  lenv:  local_env;
  n_vars: vars;
  pid: unit -> string; (* Returns the pid of the neigbhor. This info
                          is not available in all modes (e.g.,
                          anonymous) *)
  reply: unit -> int; 
  (* Returns the channel number that let this neighbor access to the
     content of the process, if the neighbor can access to the
     process.  Returns -1 if the neigbor can not access to the
     process, which can happen in directed graphs only.  This info is
     not available in all modes *)
}

type enable_fun = neighbor list -> local_env -> action list
type step_fun   = neighbor list -> local_env -> action -> local_env

(** Those 3 registering functions must be called! *)
type algo_id = string
val reg_vars : algo_id -> vars -> unit
val reg_enable : algo_id  -> enable_fun -> unit
val reg_step : algo_id  -> step_fun -> unit

(** raised by sasa if one of the function above is not called *)
exception Unregistred of string * string

(** This one is not mandatory.  The initialisation done in the dot
   file have priority over this one.  *)
val reg_init_vars : algo_id -> (neighbor list -> local_env) -> unit

(** Mandatory in custom mode only. *)
val reg_actions : algo_id -> action list -> unit

(** util(s) *)
val value_to_string : value -> string


(**/**)
(** functions below are not part of the API *)
val vart_to_rif_decl: varT -> string -> (string * string) list
val vart_to_rif_string: varT -> string -> string
val verbose_level: int ref


(** the following functions are used by sasa *)
val get_vars   : algo_id -> vars
val get_enable : algo_id -> enable_fun
val get_step   : algo_id -> step_fun 
val get_init_vars  : algo_id -> (string * varT) list -> (neighbor list -> local_env) 
val get_actions   : algo_id -> action list