(* 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/
 *)

type direction = [ `LeftToRight | `RightToLeft ]

type loc = CicNotationPt.location

type ('term, 'lazy_term, 'ident) pattern =
  'lazy_term option * ('ident * 'term) list * 'term option

type ('term, 'ident) type_spec =
   | Ident of 'ident
   | Type of UriManager.uri * int 

type 'lazy_term reduction =
  [ `Normalize
  | `Reduce
  | `Simpl
  | `Unfold of 'lazy_term option
  | `Whd ]

type ('term, 'lazy_term, 'reduction, 'ident) tactic =
  | Absurd of loc * 'term
  | Apply of loc * 'term
  | Assumption of loc
  | Auto of loc * int option * int option * string option * string option 
      (* depth, width, paramodulation, full *) (* ALB *)
  | Change of loc * ('term, 'lazy_term, 'ident) pattern * 'lazy_term
  | Clear of loc * 'ident
  | ClearBody of loc * 'ident
  | Compare of loc * 'term
  | Constructor of loc * int
  | Contradiction of loc
  | Cut of loc * 'ident option * 'term
  | DecideEquality of loc
  | Decompose of loc * ('term, 'ident) type_spec list * 'ident * 'ident list
  | Discriminate of loc * 'term
  | Elim of loc * 'term * 'term option * int option * 'ident list
  | ElimType of loc * 'term * 'term option * int option * 'ident list
  | Exact of loc * 'term
  | Exists of loc
  | Fail of loc
  | Fold of loc * 'reduction * 'lazy_term * ('term, 'lazy_term, 'ident) pattern
  | Fourier of loc
  | FwdSimpl of loc * string * 'ident list
  | Generalize of loc * ('term, 'lazy_term, 'ident) pattern * 'ident option
  | Goal of loc * int (* change current goal, argument is goal number 1-based *)
  | IdTac of loc
  | Injection of loc * 'term
  | Intros of loc * int option * 'ident list
  | Inversion of loc * 'term
  | LApply of loc * int option * 'term list * 'term * 'ident option
  | Left of loc
  | LetIn of loc * 'term * 'ident
  | Reduce of loc * 'reduction * ('term, 'lazy_term, 'ident) pattern 
  | Reflexivity of loc
  | Replace of loc * ('term, 'lazy_term, 'ident) pattern * 'lazy_term
  | Rewrite of loc * direction * 'term *
      ('term, 'lazy_term, 'ident) pattern
  | Right of loc
  | Ring of loc
  | Split of loc
  | Symmetry of loc
  | Transitivity of loc * 'term

type search_kind = [ `Locate | `Hint | `Match | `Elim ]

type print_kind = [ `Env | `Coer ]

type 'term macro = 
  (* Whelp's stuff *)
  | WHint of loc * 'term 
  | WMatch of loc * 'term 
  | WInstance of loc * 'term 
  | WLocate of loc * string
  | WElim of loc * 'term
  (* real macros *)
(*   | Abort of loc *)
  | Print of loc * string
  | Check of loc * 'term 
  | Hint of loc
  | Quit of loc
(*   | Redo of loc * int option
  | Undo of loc * int option *)
(*   | Print of loc * print_kind *)
  | Search_pat of loc * search_kind * string  (* searches with string pattern *)
  | Search_term of loc * search_kind * 'term  (* searches with term pattern *)

type alias_spec =
  | Ident_alias of string * string        (* identifier, uri *)
  | Symbol_alias of string * int * string (* name, instance no, description *)
  | Number_alias of int * string          (* instance no, description *)

(** To be increased each time the command type below changes, used for "safe"
 * marshalling *)
let magic = 5

type 'obj command =
  | Default of loc * string * UriManager.uri list
  | Include of loc * string
  | Set of loc * string * string
  | Drop of loc
  | Qed of loc
      (** name.
       * Name is needed when theorem was started without providing a name
       *)
  | Coercion of loc * UriManager.uri * bool (* add composites *)
  | Alias of loc * alias_spec
      (** parameters, name, type, fields *) 
  | Obj of loc * 'obj
  | Notation of loc * direction option * CicNotationPt.term * Gramext.g_assoc *
      int * CicNotationPt.term
      (* direction, l1 pattern, associativity, precedence, l2 pattern *)
  | Interpretation of loc *
      string * (string * CicNotationPt.argument_pattern list) *
        CicNotationPt.cic_appl_pattern
      (* description (i.e. id), symbol, arg pattern, appl pattern *)

    (* DEBUGGING *)
  | Dump of loc (* dump grammar on stdout *)
    (* DEBUGGING *)
  | Render of loc * UriManager.uri (* render library object *)

(* composed magic: term + command magics. No need to change this value *)
let magic = magic + 10000 * CicNotationPt.magic

type ('term, 'lazy_term, 'reduction, 'ident) tactical =
  | Tactic of loc * ('term, 'lazy_term, 'reduction, 'ident) tactic
  | Do of loc * int * ('term, 'lazy_term, 'reduction, 'ident) tactical
  | Repeat of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical
  | Seq of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical list
      (* sequential composition *)
  | Then of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical *
      ('term, 'lazy_term, 'reduction, 'ident) tactical list
  | First of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical list
      (* try a sequence of loc * tactical until one succeeds, fail otherwise *)
  | Try of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical
      (* try a tactical and mask failures *)
  | Solve of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical list

  | Dot of loc
  | Semicolon of loc
  | Branch of loc
  | Shift of loc
  | Pos of loc * int
  | Merge of loc
  | Focus of loc * int list
  | Unfocus of loc
  | Skip of loc

let is_punctuation =
  function
  | Dot _ | Semicolon _ | Branch _ | Shift _ | Merge _ | Pos _ -> true
  | _ -> false

type ('term, 'lazy_term, 'reduction, 'obj, 'ident) code =
  | Command of loc * 'obj command
  | Macro of loc * 'term macro 
  | Tactical of loc * ('term, 'lazy_term, 'reduction, 'ident) tactical
      * ('term, 'lazy_term, 'reduction, 'ident) tactical option(* punctuation *)
             
type ('term, 'lazy_term, 'reduction, 'obj, 'ident) comment =
  | Note of loc * string
  | Code of loc * ('term, 'lazy_term, 'reduction, 'obj, 'ident) code
             
type ('term, 'lazy_term, 'reduction, 'obj, 'ident) statement =
  | Executable of loc * ('term, 'lazy_term, 'reduction, 'obj, 'ident) code
  | Comment of loc * ('term, 'lazy_term, 'reduction, 'obj, 'ident) comment

  (* statements meaningful for matitadep *)
type dependency =
  | IncludeDep of string
  | BaseuriDep of string
  | UriDep of UriManager.uri