(* This file is part of the Catala compiler, a specification language for tax
   and social benefits computation rules. Copyright (C) 2020 Inria, contributor:
   Denis Merigoux <denis.merigoux@inria.fr>

   Licensed under the Apache License, Version 2.0 (the "License"); you may not
   use this file except in compliance with the License. You may obtain a copy of
   the License at

   http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   License for the specific language governing permissions and limitations under
   the License. *)

module type Info = sig
  type info

  val format_info : Format.formatter -> info -> unit
end

module type Id = sig
  type t
  type info

  val fresh : info -> t
  val get_info : t -> info
  val compare : t -> t -> int
  val format_t : Format.formatter -> t -> unit
  val hash : t -> int
end

module Make (X : Info) () : Id with type info = X.info = struct
  type t = { id : int; info : X.info }
  type info = X.info

  let counter = ref 0

  let fresh (info : X.info) : t =
    incr counter;
    { id = !counter; info }

  let get_info (uid : t) : X.info = uid.info
  let compare (x : t) (y : t) : int = compare x.id y.id

  let format_t (fmt : Format.formatter) (x : t) : unit =
    Format.fprintf fmt "%a" X.format_info x.info

  let hash (x : t) : int = x.id
end

module MarkedString = struct
  type info = string Pos.marked

  let format_info fmt (s, _) = Format.fprintf fmt "%s" s
end