(* Copyright (C) 2004, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * HELM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://helm.cs.unibo.it/
 *)

(* $Id$ *)

(*
type domain_item =
 | Id of (string * string option)              (* literal, opt. uri *)
 | Symbol of string * (string option * string) option (* literal, opt. (uri,interp.) *)
 | Num of (string option * string) option             (* opt. uri, interpretation *)
*)

type domain_item =
 | Id of string     (* literal *)
 | Symbol of string (* literal *)
 | Num 

exception Invalid_choice of (Stdpp.location * string) Lazy.t

module OrderedDomain =
  struct
    type t = domain_item
    (*
    let compare a b = 
      match a,b with
      | Id (x,None), Id (y,_)
      | Id (x,_), Id (y,None) when x = y -> 0
      | Symbol (x,None), Symbol (y,_)
      | Symbol (x,_), Symbol (y,None) when x = y -> 0
      | _ -> Pervasives.compare a b *)
    let compare = Pervasives.compare
  end

(* module Domain = Set.Make (OrderedDomain) *)
module Environment =
struct
  module Environment' = Map.Make (OrderedDomain)

  include Environment'

  let find k env =
    try find k env 
    with Not_found ->
           (* 
      match k with
       | Symbol (sym,_) -> find (Symbol (sym,None)) env
       | Num _ -> find (Num None) env
       | Id (id,_) -> find (Id (id,None)) env 
       *) raise Not_found

  let cons desc_of_alias k v env =
    let default_dom_item x = x in
    let env' =
      try
        let current = Environment'.find k env in
        let dsc = desc_of_alias v in
        add k (v :: (List.filter (fun x -> desc_of_alias x <> dsc) current)) env
      with Not_found ->
        add k [v] env
    in
    (* we also add default aliases *)
    let k' = default_dom_item k in
    try
      let current = find k' env' in
      let dsc = desc_of_alias v in
      add k' (v :: (List.filter (fun x -> desc_of_alias x <> dsc) current)) env'
    with Not_found ->
      add k' [v] env'

end

module InterprOD =
  struct
    type t = Stdpp.location
    let compare = Pervasives.compare
  end

module InterprEnv = Map.Make (InterprOD)

type 'term codomain_item =
  string *  (* description *)
   [`Num_interp of string -> 'term
   |`Sym_interp of 'term list -> 'term]

type interactive_user_uri_choice_type =
  selection_mode:[`SINGLE | `MULTIPLE] ->
  ?ok:string ->
  ?enable_button_for_non_vars:bool ->
  title:string -> msg:string -> id:string -> NReference.reference list ->
   NReference.reference list

type interactive_interpretation_choice_type = string -> int ->
  (Stdpp.location list * string * string) list list -> int list

type interactive_ast_choice_type = string list -> int

type input_or_locate_uri_type = 
  title:string -> ?id:string -> unit -> NReference.reference option

(*
let string_of_domain_item item =
  let f_opt f x default =
    match x with
    | None -> default
    | Some y -> f y
  in
  match item with
  | Id (s,huri) -> 
     Printf.sprintf "ID(%s,%s)" s (f_opt (fun x -> x) huri "_")
  | Symbol (s,None) -> Printf.sprintf "SYMBOL(%s)" s
  | Symbol (s,Some (_,dsc)) -> Printf.sprintf "SYMBOL(%s,%s)" s dsc
  | Num _ -> "NUM"
;;
*)
let string_of_domain_item item =
  let f_opt f x default =
    match x with
    | None -> default
    | Some y -> f y
  in
  match item with
  | Id s -> 
     Printf.sprintf "ID(%s)" s
  | Symbol s -> Printf.sprintf "SYMBOL(%s)" s
  | Num -> "NUM"
;;