open Printf
open MatitaTypes

let debug = false ;;
let debug_print = if debug then prerr_endline else ignore ;;

(** create a ProofEngineTypes.mk_fresh_name_type function which uses given
  * names as long as they are available, then it fallbacks to name generation
  * using FreshNamesGenerator module *)
let namer_of names =
  let len = List.length names in
  let count = ref 0 in
  fun metasenv context name ~typ ->
    if !count < len then begin
      let name = Cic.Name (List.nth names !count) in
      incr count;
      name
    end else
      FreshNamesGenerator.mk_fresh_name ~subst:[] metasenv context name ~typ

let tactic_of_ast = function
  | TacticAst.Intros (_, None, names) ->
      (* TODO Zack implement intros length *)
      PrimitiveTactics.intros_tac ~mk_fresh_name_callback:(namer_of names) ()
  | TacticAst.Intros (_, Some num, names) ->
      (* TODO Zack implement intros length *)
      PrimitiveTactics.intros_tac ~howmany:num
        ~mk_fresh_name_callback:(namer_of names) ()
  | TacticAst.Reflexivity _ -> Tactics.reflexivity
  | TacticAst.Assumption _ -> Tactics.assumption
  | TacticAst.Contradiction _ -> Tactics.contradiction
  | TacticAst.Exists _ -> Tactics.exists
  | TacticAst.Fourier _ -> Tactics.fourier
  | TacticAst.Goal (_, n) -> Tactics.set_goal n
  | TacticAst.Left _ -> Tactics.left
  | TacticAst.Right _ -> Tactics.right
  | TacticAst.Ring _ -> Tactics.ring
  | TacticAst.Split _ -> Tactics.split
  | TacticAst.Symmetry _ -> Tactics.symmetry
  | TacticAst.Transitivity (_, term) -> Tactics.transitivity term
  | TacticAst.Apply (_, term) -> Tactics.apply term
  | TacticAst.Absurd (_, term) -> Tactics.absurd term
  | TacticAst.Exact (_, term) -> Tactics.exact term
  | TacticAst.Cut (_, term) -> Tactics.cut term
  | TacticAst.Elim (_, term, _) ->
      (* TODO Zack implement "using" argument *)
      (* old: Tactics.elim_intros_simpl term *)
      Tactics.elim_intros term
  | TacticAst.ElimType (_, term) -> Tactics.elim_type term
  | TacticAst.Replace (_, what, with_what) -> Tactics.replace ~what ~with_what
  | TacticAst.Auto (_,depth) -> 
(*       AutoTactic.auto_tac ~num (MatitaDb.instance ()) *)
      AutoTactic.auto_tac_new ?depth ~dbd:(MatitaDb.instance ()) ()
  | TacticAst.Change (_, what, with_what, _) -> Tactics.change ~what ~with_what
(*
  (* TODO Zack a lot more of tactics to be implemented here ... *)
  | TacticAst.Change_pattern of 'term pattern * 'term * 'ident option
  | TacticAst.Change of 'term * 'term * 'ident option
  | TacticAst.Decompose of 'ident * 'ident list
  | TacticAst.Discriminate of 'ident
  | TacticAst.Fold of reduction_kind * 'term
  | TacticAst.Injection of 'ident
  | TacticAst.Replace_pattern of 'term pattern * 'term
*)
  | TacticAst.LetIn (loc,term,name) ->
      Tactics.letin term ~mk_fresh_name_callback:(namer_of [name])
  | TacticAst.ReduceAt (_,reduction_kind,ident,path) ->
      ProofEngineTypes.mk_tactic 
      (fun (((_,metasenv,_,_),goal) as status) ->
         let metano,context,ty = CicUtil.lookup_meta goal metasenv in
         let where, also_in_hypotheses = 
           if ident = "goal" then
             ty, false
           else
             let hyp = 
               try 
                 List.find (function 
                   | Some (Cic.Name name,entry) when name = ident -> true
                   | _ -> false) 
                 context
               with 
                 Not_found -> 
                   raise (ProofEngineTypes.Fail 
                            (ident ^ " is not an hypothesis"))  
             in 
             (match hyp with
             | Some (_, Cic.Decl term) -> term
             | Some (_, Cic.Def (term,ty)) -> term
             | None -> assert false),true
         in
         let pointers = CicUtil.select ~term:where ~context:path in
          (match reduction_kind with
          | `Normalize -> 
              ProofEngineTypes.apply_tactic 
                (Tactics.normalize ~also_in_hypotheses ~terms:(Some pointers)) 
                status
          | `Reduce -> 
              ProofEngineTypes.apply_tactic 
                (Tactics.reduce ~also_in_hypotheses ~terms:(Some pointers)) 
                status
          | `Simpl -> 
              ProofEngineTypes.apply_tactic 
                (Tactics.simpl ~also_in_hypotheses ~terms:(Some pointers)) 
                status
          | `Whd -> 
              ProofEngineTypes.apply_tactic 
                (Tactics.whd ~also_in_hypotheses ~terms:(Some pointers)) 
                status)) 
  | TacticAst.Reduce (_,reduction_kind,opts) ->
      let terms, also_in_hypotheses = 
        match opts with
        | Some (l,`Goal) -> Some l, false
        | Some (l,`Everywhere) -> Some l, true
        | None -> None, false
      in
      (match reduction_kind with
      | `Normalize -> Tactics.normalize ~also_in_hypotheses ~terms
      | `Reduce -> Tactics.reduce ~also_in_hypotheses ~terms
      | `Simpl -> Tactics.simpl ~also_in_hypotheses ~terms
      | `Whd -> Tactics.whd ~also_in_hypotheses ~terms) 
  | TacticAst.Rewrite (_,dir,t,ident) ->
      if dir = `Left then
        EqualityTactics.rewrite_tac ~term:t 
      else
        EqualityTactics.rewrite_back_tac ~term:t
  | TacticAst.FwdSimpl (_, name) -> 
     Tactics.fwd_simpl ~hyp:(Cic.Name name) ~dbd:(MatitaDb.instance ())
  | TacticAst.LApply (_, term, substs) ->
     let f (name, term) = Cic.Name name, term in
     Tactics.lapply ~substs:(List.map f substs) term
  | _ -> assert false

let eval_tactical status tac =
  let apply_tactic tactic =
    let (proof, goals) =
      ProofEngineTypes.apply_tactic tactic (MatitaMisc.get_proof_status status)
    in
    let new_status =
      match goals with
      | [] -> 
          let (_,metasenv,_,_) = proof in
          (match metasenv with
          | [] -> Proof proof
          | (ng,_,_)::_ -> Incomplete_proof (proof,ng))
      | ng::_ -> Incomplete_proof (proof, ng)
    in
    { status with proof_status = new_status }
  in
  let rec tactical_of_ast = function
    | TacticAst.Tactic (loc, tactic) -> tactic_of_ast tactic
    | TacticAst.Fail loc -> Tacticals.fail
    | TacticAst.Do (loc, num, tactical) ->
        Tacticals.do_tactic num (tactical_of_ast tactical)
    | TacticAst.IdTac loc -> Tacticals.id_tac
    | TacticAst.Repeat (loc, tactical) ->
        Tacticals.repeat_tactic (tactical_of_ast tactical)
    | TacticAst.Seq (loc, tacticals) ->  (* tac1; tac2; ... *)
        Tacticals.seq (List.map tactical_of_ast tacticals)
    | TacticAst.Then (loc, tactical, tacticals) ->  (* tac; [ tac1 | ... ] *)
        Tacticals.thens (tactical_of_ast tactical)
          (List.map tactical_of_ast tacticals)
    | TacticAst.Tries (loc, tacticals) ->
        Tacticals.try_tactics
          (List.map (fun t -> "", tactical_of_ast t) tacticals)
    | TacticAst.Try (loc, tactical) ->
        Tacticals.try_tactic (tactical_of_ast tactical)
  in
  apply_tactic (tactical_of_ast tac)

let eval_coercion status coercion = 
  let coer_uri,coer_ty =
    match coercion with 
    | Cic.Const (uri,_)
    | Cic.Var (uri,_) ->
        let o,_ = 
          CicEnvironment.get_obj CicUniv.empty_ugraph uri 
        in
        (match o with
        | Cic.Constant (_,_,ty,_,_)
        | Cic.Variable (_,_,ty,_,_) ->
            uri,ty
        | _ -> assert false)
    | Cic.MutConstruct (uri,t,c,_) ->
        let o,_ = 
          CicEnvironment.get_obj CicUniv.empty_ugraph uri 
        in
        (match o with
        | Cic.InductiveDefinition (l,_,_,_) ->
            let (_,_,_,cl) = List.nth l t in
            let (_,cty) = List.nth cl c in
              uri,cty
        | _ -> assert false)
    | _ -> assert false 
  in
  (* we have to get the source and the tgt type uri 
   * in Coq syntax we have already their names, but 
   * since we don't support Funclass and similar I think
   * all the coercion should be of the form
   * (A:?)(B:?)T1->T2
   * So we should be able to extract them from the coercion type
   *)
  let extract_last_two_p ty =
    let rec aux = function
      | Cic.Prod( _, src, Cic.Prod (n,t1,t2)) -> aux (Cic.Prod(n,t1,t2))   
      | Cic.Prod( _, src, tgt) -> src, tgt
      | _ -> assert false
    in  
    aux ty
  in
  let ty_src,ty_tgt = extract_last_two_p coer_ty in
  let context = [] in 
  let src_uri = 
    let ty_src = CicReduction.whd context ty_src in
    UriManager.uri_of_string (CicUtil.uri_of_term ty_src) 
  in
  let tgt_uri = 
    let ty_tgt = CicReduction.whd context ty_tgt in
    UriManager.uri_of_string (CicUtil.uri_of_term ty_tgt) 
  in
  let new_coercions =
    (* also adds them to the Db *)
    CoercGraph.close_coercion_graph src_uri tgt_uri coer_uri in
  let status =
   List.fold_left (fun s (uri,o,ugraph) -> MatitaSync.add_obj uri o status)
    status new_coercions in
  {status with proof_status = No_proof}

let generate_elimination_principles uri status =
 let elim sort status =
   try
    let uri,obj = CicElim.elim_of ~sort uri 0 in
     MatitaSync.add_obj uri obj status
   with CicElim.Can_t_eliminate -> status
 in
 List.fold_left (fun status sort -> elim sort status) status
  [ Cic.Prop; Cic.Set; (Cic.Type (CicUniv.fresh ())) ]

let generate_projections uri fields status =
 let projections = CicRecord.projections_of uri fields in
  List.fold_left
   (fun status (uri, name, bo) -> 
     try 
      let ty, ugraph = 
        CicTypeChecker.type_of_aux' [] [] bo CicUniv.empty_ugraph in
      let bo = Unshare.unshare bo in
      let ty = Unshare.unshare ty in
      let attrs = [`Class `Projection; `Generated] in
      let obj = Cic.Constant (name,Some bo,ty,[],attrs) in
       MatitaSync.add_obj uri obj status
     with
        CicTypeChecker.TypeCheckerFailure s ->
         MatitaLog.message 
          ("Unable to create projection " ^ name ^ " cause: " ^ s);
         status
      | CicEnvironment.Object_not_found uri ->
         let depend = UriManager.name_of_uri uri in
          MatitaLog.message 
           ("Unable to create projection " ^ name ^ " because it requires " ^ depend);
         status
  ) status projections
 
let eval_command status cmd =
  match cmd with
  | TacticAst.Set (loc, name, value) -> set_option status name value
  | TacticAst.Qed loc ->
      let uri, metasenv, bo, ty = 
        match status.proof_status with
        | Proof (Some uri, metasenv, body, ty) ->
            uri, metasenv, body, ty
        | Proof (None, metasenv, body, ty) -> 
            command_error 
              ("Someone allows to start a thm without giving the "^
               "name/uri. This should be fixed!")
        | _-> command_error "You can't qed an uncomplete theorem"
      in
      let suri = UriManager.string_of_uri uri in
      if metasenv <> [] then 
        command_error "Proof not completed! metasenv is not empty!";
      let name = UriManager.name_of_uri uri in
      let obj = Cic.Constant (name,Some bo,ty,[],[]) in
      MatitaSync.add_obj uri obj status
  | TacticAst.Coercion (loc, coercion) -> 
      eval_coercion status coercion
  | TacticAst.Alias (loc, spec) -> 
     (match spec with
      | TacticAst.Ident_alias (id,uri) -> 
          {status with aliases = 
            DisambiguateTypes.Environment.add 
              (DisambiguateTypes.Id id) 
              ("boh?",(fun _ _ _ -> CicUtil.term_of_uri uri)) 
              status.aliases }
      | TacticAst.Symbol_alias (symb, instance, desc) ->
          {status with aliases = 
            DisambiguateTypes.Environment.add 
              (DisambiguateTypes.Symbol (symb,instance))
              (DisambiguateChoices.lookup_symbol_by_dsc symb desc) 
              status.aliases }
      | TacticAst.Number_alias (instance,desc) ->
          {status with aliases = 
            DisambiguateTypes.Environment.add 
              (DisambiguateTypes.Num instance) 
              (DisambiguateChoices.lookup_num_by_dsc desc) status.aliases })
  | TacticAst.Obj (loc,obj) ->
     let ext,name =
      match obj with
         Cic.Constant (name,_,_,_,_)
       | Cic.CurrentProof (name,_,_,_,_,_) -> ".con",name
       | Cic.InductiveDefinition (types,_,_,_) ->
          ".ind",
          (match types with (name,_,_,_)::_ -> name | _ -> assert false)
       | _ -> assert false in
     let uri = 
       UriManager.uri_of_string (MatitaMisc.qualify status name ^ ext) 
     in
     let metasenv = MatitaMisc.get_proof_metasenv status in
     match obj with
        Cic.CurrentProof (_,metasenv',bo,ty,_,_) ->
         assert (metasenv = metasenv');
         let goalno =
          match metasenv' with (goalno,_,_)::_ -> goalno | _ -> assert false in
         let initial_proof = (Some uri, metasenv, bo, ty) in
          { status with proof_status = Incomplete_proof (initial_proof,goalno)}
      | _ ->
        if metasenv <> [] then
         command_error (
           "metasenv not empty while giving a definition with body: " ^
           CicMetaSubst.ppmetasenv metasenv []);
        let status = MatitaSync.add_obj uri obj status in
         match obj with
            Cic.Constant _ -> status
          | Cic.InductiveDefinition (_,_,_,attrs) ->
             let status = generate_elimination_principles uri status in
             let rec get_record_attrs =
              function
                 [] -> None
               | (`Class (`Record fields))::_ -> Some fields
               | _::tl -> get_record_attrs tl
             in
              (match get_record_attrs attrs with
                  None -> status (* not a record *)
                | Some fields -> generate_projections uri fields status)
          | Cic.CurrentProof _
          | Cic.Variable _ -> assert false

let eval_executable status ex =
  match ex with
  | TacticAst.Tactical (_, tac) -> eval_tactical status tac
  | TacticAst.Command (_, cmd) -> eval_command status cmd
  | TacticAst.Macro (_, mac) -> 
      command_error (sprintf "The macro %s can't be in a script" 
        (TacticAstPp.pp_macro_cic mac))

let eval_comment status c = status
            
let eval status st =
  match st with
  | TacticAst.Executable (_,ex) -> eval_executable status ex
  | TacticAst.Comment (_,c) -> eval_comment status c

let disambiguate_term status term =
  let (aliases, metasenv, cic, _) =
    match
      MatitaDisambiguator.disambiguate_term ~dbd:(MatitaDb.instance ())
        ~aliases:(status.aliases) ~context:(MatitaMisc.get_proof_context status)
        ~metasenv:(MatitaMisc.get_proof_metasenv status) term
    with
    | [x] -> x
    | _ -> assert false
  in
  let proof_status =
    match status.proof_status with
    | No_proof -> Intermediate metasenv
    | Incomplete_proof ((uri, _, proof, ty), goal) ->
        Incomplete_proof ((uri, metasenv, proof, ty), goal)
    | Intermediate _ -> Intermediate metasenv 
    | Proof _ -> assert false
  in
  let status =
    { status with
        aliases = aliases;
        proof_status = proof_status }
  in
  status, cic
  
let disambiguate_obj status obj =
  let uri =
   match obj with
      TacticAst.Inductive (_,(name,_,_,_)::_)
    | TacticAst.Record (_,name,_,_) ->
       Some (UriManager.uri_of_string (MatitaMisc.qualify status name ^ ".ind"))
    | TacticAst.Inductive _ -> assert false
    | _ -> None in
  let (aliases, metasenv, cic, _) =
    match
      MatitaDisambiguator.disambiguate_obj ~dbd:(MatitaDb.instance ())
        ~aliases:(status.aliases) ~uri obj
    with
    | [x] -> x
    | _ -> assert false
  in
  let proof_status =
    match status.proof_status with
    | No_proof -> Intermediate metasenv
    | Incomplete_proof _
    | Intermediate _
    | Proof _ -> assert false
  in
  let status =
    { status with
        aliases = aliases;
        proof_status = proof_status }
  in
  status, cic
  
let disambiguate_tactic status = function
  | TacticAst.Transitivity (loc, term) -> 
      let status, cic = disambiguate_term status term in
      status, TacticAst.Transitivity (loc, cic)
  | TacticAst.Apply (loc, term) ->
      let status, cic = disambiguate_term status term in
      status, TacticAst.Apply (loc, cic)
  | TacticAst.Absurd (loc, term) -> 
      let status, cic = disambiguate_term status term in
      status, TacticAst.Absurd (loc, cic)
  | TacticAst.Exact (loc, term) -> 
      let status, cic = disambiguate_term status term in
      status, TacticAst.Exact (loc, cic)
  | TacticAst.Cut (loc, term) -> 
      let status, cic = disambiguate_term status term in
      status, TacticAst.Cut (loc, cic)
  | TacticAst.Elim (loc, term, Some term') ->
      let status, cic1 = disambiguate_term status term in
      let status, cic2 = disambiguate_term status term' in
      status, TacticAst.Elim (loc, cic1, Some cic2)
  | TacticAst.Elim (loc, term, None) ->
      let status, cic = disambiguate_term status term in
      status, TacticAst.Elim (loc, cic, None)
  | TacticAst.ElimType (loc, term) -> 
      let status, cic = disambiguate_term status term in
      status, TacticAst.ElimType (loc, cic)
  | TacticAst.Replace (loc, what, with_what) -> 
      let status, cic1 = disambiguate_term status what in
      let status, cic2 = disambiguate_term status with_what in
      status, TacticAst.Replace (loc, cic1, cic2)
  | TacticAst.Change (loc, what, with_what, ident) -> 
      let status, cic1 = disambiguate_term status what in
      let status, cic2 = disambiguate_term status with_what in
      status, TacticAst.Change (loc, cic1, cic2, ident)
(*
  (* TODO Zack a lot more of tactics to be implemented here ... *)
  | TacticAst.Change_pattern of 'term pattern * 'term * 'ident option
  | TacticAst.Change of 'term * 'term * 'ident option
  | TacticAst.Decompose of 'ident * 'ident list
  | TacticAst.Discriminate of 'ident
  | TacticAst.Fold of reduction_kind * 'term
  | TacticAst.Injection of 'ident
  | TacticAst.Replace_pattern of 'term pattern * 'term
*)
  | TacticAst.LetIn (loc,term,name) ->
      let status, term = disambiguate_term status term in
      status, TacticAst.LetIn (loc,term,name)
  | TacticAst.ReduceAt (loc, reduction_kind, ident, path) ->
      let path = Disambiguate.interpretate_path [] status.aliases path in
      status, TacticAst.ReduceAt(loc, reduction_kind, ident, path)
  | TacticAst.Reduce (loc, reduction_kind, opts) ->
      let status, opts = 
        match opts with
        | None -> status, None
        | Some (l,pat) -> 
            let status, l = 
              List.fold_right (fun t (status,acc) ->
                let status',t' = disambiguate_term status t in
                status', t'::acc) 
              l (status,[]) 
            in
            status, Some (l, pat)
      in
      status, TacticAst.Reduce (loc, reduction_kind, opts)
  | TacticAst.Rewrite (loc,dir,t,ident) ->
      let status, term = disambiguate_term status t in
      status, TacticAst.Rewrite (loc,dir,term,ident)
  | TacticAst.Intros (loc, num, names) ->
      status, TacticAst.Intros (loc, num, names)
  | TacticAst.Auto (loc,num) -> status, TacticAst.Auto (loc,num)
  | TacticAst.Reflexivity loc -> status, TacticAst.Reflexivity loc
  | TacticAst.Assumption loc -> status, TacticAst.Assumption loc
  | TacticAst.Contradiction loc -> status, TacticAst.Contradiction loc
  | TacticAst.Exists loc -> status, TacticAst.Exists loc 
  | TacticAst.Fourier loc -> status, TacticAst.Fourier loc
  | TacticAst.Left loc -> status, TacticAst.Left loc
  | TacticAst.Right loc -> status, TacticAst.Right loc
  | TacticAst.Ring loc -> status, TacticAst.Ring loc
  | TacticAst.Split loc -> status, TacticAst.Split loc
  | TacticAst.Symmetry loc -> status, TacticAst.Symmetry loc
  | TacticAst.Goal (loc, g) -> status, TacticAst.Goal (loc, g)
  | TacticAst.FwdSimpl (loc, name) -> status, TacticAst.FwdSimpl (loc, name)  
  | TacticAst.LApply (loc, term, substs) ->
     let f (status, substs) (name, term) =
        let status, term = disambiguate_term status term in
	status, (name, term) :: substs
     in
     let status, term = disambiguate_term status term in
     let status, substs = List.fold_left f (status, []) substs in 
     status, TacticAst.LApply (loc, term, substs)
  
  | x -> 
      print_endline ("Not yet implemented:" ^ TacticAstPp.pp_tactic x);
      assert false

let rec disambiguate_tactical status = function 
  | TacticAst.Tactic (loc, tactic) -> 
      let status, tac = disambiguate_tactic status tactic in
      status, TacticAst.Tactic (loc, tac)
  | TacticAst.Do (loc, num, tactical) ->
      let status, tac = disambiguate_tactical status tactical in
      status, TacticAst.Do (loc, num, tac)
  | TacticAst.Repeat (loc, tactical) -> 
      let status, tac = disambiguate_tactical status tactical in
      status, TacticAst.Repeat (loc, tac)
  | TacticAst.Seq (loc, tacticals) ->  (* tac1; tac2; ... *)
      let status, tacticals = disambiguate_tacticals status tacticals in
      let tacticals = List.rev tacticals in
      status, TacticAst.Seq (loc, tacticals)
  | TacticAst.Then (loc, tactical, tacticals) ->  (* tac; [ tac1 | ... ] *)
      let status, tactical = disambiguate_tactical status tactical in
      let status, tacticals = disambiguate_tacticals status tacticals in
      status, TacticAst.Then (loc, tactical, tacticals)
  | TacticAst.Tries (loc, tacticals) ->
      let status, tacticals = disambiguate_tacticals status tacticals in
      status, TacticAst.Tries (loc, tacticals)
  | TacticAst.Try (loc, tactical) ->
      let status, tactical = disambiguate_tactical status tactical in
      status, TacticAst.Try (loc, tactical)
  | (TacticAst.IdTac _ | TacticAst.Fail _) as tac ->
      status, tac

and disambiguate_tacticals status tacticals =
  let status, tacticals =
    List.fold_left
      (fun (status, tacticals) tactical ->
        let status, tac = disambiguate_tactical status tactical in
        status, tac :: tacticals)
      (status, [])
      tacticals
  in
  let tacticals = List.rev tacticals in
  status, tacticals
  
let disambiguate_command status = function
  | TacticAst.Coercion (loc, term) ->
      let status, term = disambiguate_term status term in
      status, TacticAst.Coercion (loc,term)
  | (TacticAst.Set _ | TacticAst.Qed _) as cmd ->
      status, cmd
  | TacticAst.Alias _ as x -> status, x
  | TacticAst.Obj (loc,obj) ->
      let status,obj = disambiguate_obj status obj in
       status, TacticAst.Obj (loc,obj)

let disambiguate_executable status ex =
  match ex with
  | TacticAst.Tactical (loc, tac) ->
      let status, tac = disambiguate_tactical status tac in
      status, (TacticAst.Tactical (loc, tac))
  | TacticAst.Command (loc, cmd) ->
      let status, cmd = disambiguate_command status cmd in
      status, (TacticAst.Command (loc, cmd))
  | TacticAst.Macro (_, mac) -> 
      command_error (sprintf "The macro %s can't be in a script" 
        (TacticAstPp.pp_macro_ast mac))

let disambiguate_comment status c = 
  match c with
  | TacticAst.Note (loc,n) -> status, TacticAst.Note (loc,n)
  | TacticAst.Code (loc,ex) -> 
        let status, ex = disambiguate_executable status ex in
        status, TacticAst.Code (loc,ex)
        
let disambiguate_statement status statement =
  match statement with
  | TacticAst.Comment (loc,c) -> 
        let status, c = disambiguate_comment status c in
        status, TacticAst.Comment (loc,c)
  | TacticAst.Executable (loc,ex) -> 
        let status, ex = disambiguate_executable status ex in
        status, TacticAst.Executable (loc,ex)
  
let eval_ast status ast =
  let status,st = disambiguate_statement status ast in
  (* this disambiguation step should be deferred to support tacticals *)
  eval status st

let eval_from_stream status str cb =
  let stl = CicTextualParser2.parse_statements str in
  List.fold_left 
    (fun status ast -> cb status ast;eval_ast status ast) status 
  stl
  
let eval_string status str =
  eval_from_stream status (Stream.of_string str) (fun _ _ -> ())

let default_options () =
  let options =
    StringMap.add "baseuri"
      (String
        (Helm_registry.get "matita.baseuri" ^ Helm_registry.get "matita.owner"))
      no_options
  in
  let options =
    StringMap.add "basedir"
      (String (Helm_registry.get "matita.basedir" ))
      options
  in
  options

let initial_status =
  lazy {
    aliases = DisambiguateTypes.empty_environment;
    proof_status = No_proof;
    options = default_options ();
    objects = [];
  }