(* Copyright (C) 2000-2002, 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://cs.unibo.it/helm/.
 *)

(******************************************************************************)
(*                                                                            *)
(*                               PROJECT HELM                                 *)
(*                                                                            *)
(*                Claudio Sacerdoti Coen <sacerdot@cs.unibo.it>               *)
(*                                 06/01/2002                                 *)
(*                                                                            *)
(*                                                                            *)
(******************************************************************************)

open Printf

(* A WIDGET TO ENTER CIC TERMS *)

class type term_editor =
 object
   method coerce : GObj.widget
   (* get_as_string returns the unquoted string *)
   method get_as_string : string
   method get_metasenv_and_term :
     context:Cic.context ->
     metasenv:Cic.metasenv -> Cic.metasenv * Cic.term
   method reset : unit
   (* The input of set_term is unquoted *)
   method set_term : string -> unit
   method environment : DisambiguatingParser.EnvironmentP3.t ref
 end

module Make(C:DisambiguateTypes.Callbacks) =
  struct

   module Disambiguate' = DisambiguatingParser.Make(C);;

   class term_editor_impl ~(dbh:Dbi.connection) ?packing ?width ?height
    ?isnotempty_callback ?share_environment_with () : term_editor
   =
    let environment =
     match share_environment_with with
        None -> ref
          (DisambiguatingParser.EnvironmentP3.of_string
            DisambiguatingParser.EnvironmentP3.empty)
      | Some obj -> obj#environment
    in
    let input = GText.view ~editable:true ?width ?height ?packing () in
    let _ =
     match isnotempty_callback with
        None -> ()
      | Some callback ->
         ignore(input#buffer#connect#changed
          (function () -> callback (input#buffer#char_count > 0)))
    in
     object(self)

      method coerce = input#coerce

      method reset =
       input#buffer#delete input#buffer#start_iter input#buffer#end_iter
      (* CSC: txt is now a string, but should be of type Cic.term *)

      method set_term txt =
       self#reset ;
       ignore (input#buffer#insert txt)

      (* CSC: this method should disappear *)
      (* get_as_string returns the unquoted string *)
      method get_as_string = input#buffer#get_text ()

      method get_metasenv_and_term ~context ~metasenv =
       let name_context =
        List.map
         (function
             Some (n,_) -> Some n
           | None -> None
         ) context
       in
        let environment',metasenv,expr =
         match
          Disambiguate'.disambiguate_term ~dbh context metasenv
           (input#buffer#get_text ()) !environment
         with
            [environment',metasenv,expr] -> environment',metasenv,expr
          | _ -> assert false
        in
        environment := environment';
        (metasenv, expr)

      method environment = environment
   end

   let term_editor = new term_editor_impl

end