(*
    ||M||  This file is part of HELM, an Hypertextual, Electronic        
    ||A||  Library of Mathematics, developed at the Computer Science     
    ||T||  Department, University of Bologna, Italy.                     
    ||I||                                                                
    ||T||  HELM is free software; you can redistribute it and/or         
    ||A||  modify it under the terms of the GNU General Public License   
    \   /  version 2 or (at your option) any later version.      
     \ /   This software is distributed as is, NO WARRANTY.     
      V_______________________________________________________________ *)

(* $Id: nCic.ml 9058 2008-10-13 17:42:30Z tassi $ *)

open Printf

let debug = false
let debug_print s = if debug then prerr_endline (Lazy.force s) else ()

open Continuationals.Stack
open NTacStatus
module Ast = CicNotationPt

(* =================================== paramod =========================== *)
let auto_paramod ~params:(l,_) status goal =
  let gty = get_goalty status goal in
  let n,h,metasenv,subst,o = status#obj in
  let status,t = term_of_cic_term status gty (ctx_of gty) in
  let status, l = 
    List.fold_left
      (fun (status, l) t ->
        let status, t = disambiguate status t None (ctx_of gty) in
        let status, ty = typeof status (ctx_of t) t in
        let status, t =  term_of_cic_term status t (ctx_of gty) in
        let status, ty = term_of_cic_term status ty (ctx_of ty) in
        (status, (t,ty) :: l))
      (status,[]) l
  in
  match
    NCicParamod.nparamod status metasenv subst (ctx_of gty) (NCic.Rel ~-1,t) l 
  with
  | [] -> raise (NTacStatus.Error (lazy "no proof found",None))
  | (pt, metasenv, subst)::_ -> 
      let status = status#set_obj (n,h,metasenv,subst,o) in
      instantiate status goal (NTacStatus.mk_cic_term (ctx_of gty) pt)
;;

let auto_paramod_tac ~params status = 
  NTactics.distribute_tac (auto_paramod ~params) status
;;

(* =================================== auto =========================== *)
let auto_tac ~params status =
  prerr_endline "I teoremi noti sono";
  NDiscriminationTree.DiscriminationTree.iter status#auto_cache
    (fun _ t -> 
      List.iter (fun t ->
       prerr_endline
        (NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] t))
       (NDiscriminationTree.TermSet.elements t));
  status
;;

(* ========================= dispatching of auto/auto_paramod ============ *)
let auto_tac ~params:(_,flags as params) =
  if List.mem_assoc "paramodulation" flags then 
    auto_paramod_tac ~params  
  else 
    auto_tac ~params
;;

(* EOF *)