(*  Title:      Pure/Isar/generic_target.ML

    Author:     Makarius

    Author:     Florian Haftmann, TU Muenchen

Common target infrastructure.

*)

signature GENERIC_TARGET =

sig

  val define: (((binding * typ) * mixfix) * (binding * term) ->

      term list * term list -> local_theory -> (term * thm) * local_theory) ->

    bool -> (binding * mixfix) * (Attrib.binding * term) -> local_theory ->

    (term * (string * thm)) * local_theory

  val notes:

    (string -> (Attrib.binding * (thm list * Args.src list) list) list ->

      (Attrib.binding * (thm list * Args.src list) list) list -> local_theory -> local_theory) ->

    string -> (Attrib.binding * (thm list * Args.src list) list) list -> local_theory ->

    (string * thm list) list * local_theory

  val locale_notes: string -> string ->

    (Attrib.binding * (thm list * Args.src list) list) list ->

    (Attrib.binding * (thm list * Args.src list) list) list ->

    local_theory -> local_theory

  val abbrev: (string * bool -> binding * mixfix -> term * term ->

      term list -> local_theory -> local_theory) ->

    string * bool -> (binding * mixfix) * term -> local_theory -> (term * term) * local_theory

  val background_declaration: declaration -> local_theory -> local_theory

  val locale_declaration: string -> bool -> declaration -> local_theory -> local_theory

  val standard_declaration: (int -> bool) -> declaration -> local_theory -> local_theory

  val generic_const: bool -> Syntax.mode -> (binding * mixfix) * term ->

    Context.generic -> Context.generic

  val const_declaration: (int -> bool) -> Syntax.mode -> (binding * mixfix) * term ->

    local_theory -> local_theory

  val background_foundation: ((binding * typ) * mixfix) * (binding * term) ->

    term list * term list -> local_theory -> (term * thm) * local_theory

  val theory_foundation: ((binding * typ) * mixfix) * (binding * term) ->

    term list * term list -> local_theory -> (term * thm) * local_theory

  val theory_notes: string ->

    (Attrib.binding * (thm list * Args.src list) list) list ->

    (Attrib.binding * (thm list * Args.src list) list) list ->

    local_theory -> local_theory

  val theory_abbrev: Syntax.mode -> (binding * mixfix) -> term * term -> term list ->

    local_theory -> local_theory

  val theory_declaration: declaration -> local_theory -> local_theory

end

structure Generic_Target: GENERIC_TARGET =

struct

(** lifting primitive to target operations **)

(* mixfix syntax *)

fun check_mixfix ctxt (b, extra_tfrees) mx =

  if null extra_tfrees then mx

  else

    (Context_Position.if_visible ctxt warning

      ("Additional type variable(s) in specification of " ^ Binding.print b ^ ": " ^

        commas (map (Syntax.string_of_typ ctxt o TFree) (sort_wrt #1 extra_tfrees)) ^

        (if mx = NoSyn then ""

         else "\nDropping mixfix syntax " ^ Pretty.string_of (Mixfix.pretty_mixfix mx)));

      NoSyn);

(* define *)

fun define foundation internal ((b, mx), ((b_def, atts), rhs)) lthy =

  let

    val thy = Proof_Context.theory_of lthy;

    val thy_ctxt = Proof_Context.init_global thy;

    (*term and type parameters*)

    val ((defs, _), rhs') = Thm.cterm_of thy rhs

      |> Local_Defs.export_cterm lthy thy_ctxt ||> Thm.term_of;

    val xs = Variable.add_fixed lthy rhs' [];

    val T = Term.fastype_of rhs;

    val tfreesT = Term.add_tfreesT T (fold (Term.add_tfreesT o #2) xs []);

    val extra_tfrees = rev (subtract (op =) tfreesT (Term.add_tfrees rhs []));

    val mx' = check_mixfix lthy (b, extra_tfrees) mx;

    val type_params = map (Logic.mk_type o TFree) extra_tfrees;

    val term_params = map Free (sort (Variable.fixed_ord lthy o pairself #1) xs);

    val params = type_params @ term_params;

    val U = map Term.fastype_of params ---> T;

    (*foundation*)

    val ((lhs', global_def), lthy2) = lthy

      |> foundation (((b, U), mx'), (b_def, rhs')) (type_params, term_params);

    (*local definition*)

    val ((lhs, local_def), lthy3) = lthy2

      |> Local_Defs.add_def ((b, NoSyn), lhs');

    (*result*)

    val def =

      Thm.transitive local_def global_def

      |> Local_Defs.contract defs

          (Thm.cterm_of (Proof_Context.theory_of lthy3) (Logic.mk_equals (lhs, rhs)));

    val ([(res_name, [res])], lthy4) = lthy3

      |> Local_Theory.notes [((if internal then Binding.empty else b_def, atts), [([def], [])])];

  in ((lhs, (res_name, res)), lthy4) end;

(* notes *)

local

fun import_export_proof ctxt (name, raw_th) =

  let

    val thy = Proof_Context.theory_of ctxt;

    val thy_ctxt = Proof_Context.init_global thy;

    val certT = Thm.ctyp_of thy;

    val cert = Thm.cterm_of thy;

    (*export assumes/defines*)

    val th = Goal.norm_result raw_th;

    val ((defs, asms), th') = Local_Defs.export ctxt thy_ctxt th;

    val asms' = map (Raw_Simplifier.rewrite_rule defs) asms;

    (*export fixes*)

    val tfrees = map TFree (Thm.fold_terms Term.add_tfrees th' []);

    val frees = map Free (Thm.fold_terms Term.add_frees th' []);

    val (th'' :: vs) =

      (th' :: map (Drule.mk_term o cert) (map Logic.mk_type tfrees @ frees))

      |> Variable.export ctxt thy_ctxt

      |> Drule.zero_var_indexes_list;

    (*thm definition*)

    val result = Global_Theory.name_thm true true name th'';

    (*import fixes*)

    val (tvars, vars) =

      chop (length tfrees) (map (Thm.term_of o Drule.dest_term) vs)

      |>> map Logic.dest_type;

    val instT = map_filter (fn (TVar v, T) => SOME (v, T) | _ => NONE) (tvars ~~ tfrees);

    val inst = filter (is_Var o fst) (vars ~~ frees);

    val cinstT = map (pairself certT o apfst TVar) instT;

    val cinst = map (pairself (cert o Term.map_types (Term_Subst.instantiateT instT))) inst;

    val result' = Thm.instantiate (cinstT, cinst) result;

    (*import assumes/defines*)

    val result'' =

      (fold (curry op COMP) asms' result'

        handle THM _ => raise THM ("Failed to re-import result", 0, result' :: asms'))

      |> Local_Defs.contract defs (Thm.cprop_of th)

      |> Goal.norm_result

      |> Global_Theory.name_thm false false name;

  in (result'', result) end;

fun standard_facts lthy ctxt =

  Element.transform_facts (Local_Theory.standard_morphism lthy ctxt);

in

fun notes target_notes kind facts lthy =

  let

    val facts' = facts

      |> map (fn (a, bs) => (a, Global_Theory.burrow_fact (Global_Theory.name_multi

          (Local_Theory.full_name lthy (fst a))) bs))

      |> Global_Theory.map_facts (import_export_proof lthy);

    val local_facts = Global_Theory.map_facts #1 facts';

    val global_facts = Global_Theory.map_facts #2 facts';

  in

    lthy

    |> target_notes kind global_facts (Attrib.partial_evaluation lthy local_facts)

    |> Attrib.local_notes kind local_facts

  end;

fun locale_notes locale kind global_facts local_facts =

  Local_Theory.background_theory

    (Attrib.global_notes kind (Attrib.map_facts (K []) global_facts) #> snd) #>

  (fn lthy => lthy |>

    Local_Theory.target (fn ctxt => ctxt |>

      Locale.add_thmss locale kind (standard_facts lthy ctxt local_facts))) #>

  (fn lthy => lthy |>

    Local_Theory.map_contexts (fn level => fn ctxt =>

      if level = 0 orelse level = Local_Theory.level lthy then ctxt

      else ctxt |> Attrib.local_notes kind (standard_facts lthy ctxt local_facts) |> snd));

end;

(* abbrev *)

fun abbrev target_abbrev prmode ((b, mx), t) lthy =

  let

    val thy_ctxt = Proof_Context.init_global (Proof_Context.theory_of lthy);

    val target_ctxt = Local_Theory.target_of lthy;

    val t' = Assumption.export_term lthy target_ctxt t;

    val xs = map Free (rev (Variable.add_fixed lthy t' []));

    val u = fold_rev lambda xs t';

    val extra_tfrees =

      subtract (op =) (Term.add_tfreesT (Term.fastype_of u) []) (Term.add_tfrees u []);

    val mx' = check_mixfix lthy (b, extra_tfrees) mx;

    val global_rhs =

      singleton (Variable.export_terms (Variable.declare_term u target_ctxt) thy_ctxt) u;

  in

    lthy

    |> target_abbrev prmode (b, mx') (global_rhs, t') xs

    |> Proof_Context.add_abbrev Print_Mode.internal (b, t) |> snd

    |> Local_Defs.fixed_abbrev ((b, NoSyn), t)

  end;

(* declaration *)

fun background_declaration decl lthy =

  let

    val theory_decl =

      Local_Theory.standard_form lthy

        (Proof_Context.init_global (Proof_Context.theory_of lthy)) decl;

  in Local_Theory.background_theory (Context.theory_map theory_decl) lthy end;

fun locale_declaration locale syntax decl lthy = lthy

  |> Local_Theory.target (fn ctxt => ctxt |>

    Locale.add_declaration locale syntax

      (Morphism.transform (Local_Theory.standard_morphism lthy ctxt) decl));

fun standard_declaration pred decl lthy =

  Local_Theory.map_contexts (fn level => fn ctxt =>

    if pred level then Context.proof_map (Local_Theory.standard_form lthy ctxt decl) ctxt

    else ctxt) lthy;

(* const declaration *)

fun generic_const same_shape prmode ((b, mx), t) context =

  let

    val const_alias =

      if same_shape then

        (case t of

          Const (c, T) =>

            let

              val thy = Context.theory_of context;

              val ctxt = Context.proof_of context;

              val t' = Syntax.check_term ctxt (Const (c, dummyT))

                |> singleton (Variable.polymorphic ctxt);

            in

              (case t' of

                Const (c', T') =>

                  if c = c' andalso Sign.typ_equiv thy (T, T') then SOME c else NONE

              | _ => NONE)

            end

        | _ => NONE)

      else NONE;

  in

    (case const_alias of

      SOME c =>

        context

        |> Context.mapping (Sign.const_alias b c) (Proof_Context.const_alias b c)

        |> Morphism.form (Proof_Context.generic_notation true prmode [(t, mx)])

    | NONE =>

        context

        |> Proof_Context.generic_add_abbrev Print_Mode.internal (b, Term.close_schematic_term t)

        |-> (fn (const as Const (c, _), _) => same_shape ?

              (Proof_Context.generic_revert_abbrev (#1 prmode) c #>

               Morphism.form (Proof_Context.generic_notation true prmode [(const, mx)]))))

  end;

fun const_declaration pred prmode ((b, mx), rhs) =

  standard_declaration pred (fn phi =>

    let

      val b' = Morphism.binding phi b;

      val rhs' = Morphism.term phi rhs;

      val same_shape = Term.aconv_untyped (rhs, rhs');

    in generic_const same_shape prmode ((b', mx), rhs') end);

(** primitive theory operations **)

fun background_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params) lthy =

  let

    val (const, lthy2) = lthy

      |> Local_Theory.background_theory_result (Sign.declare_const lthy ((b, U), mx));

    val lhs = list_comb (const, type_params @ term_params);

    val ((_, def), lthy3) = lthy2

      |> Local_Theory.background_theory_result

        (Thm.add_def lthy2 false false

          (Thm.def_binding_optional b b_def, Logic.mk_equals (lhs, rhs)));

  in ((lhs, def), lthy3) end;

fun theory_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params) =

  background_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params)

  #-> (fn (lhs, def) => fn lthy' => lthy' |>

        const_declaration (fn level => level <> Local_Theory.level lthy')

          Syntax.mode_default ((b, mx), lhs)

    |> pair (lhs, def));

fun theory_notes kind global_facts local_facts =

  Local_Theory.background_theory (Attrib.global_notes kind global_facts #> snd) #>

  (fn lthy => lthy |> Local_Theory.map_contexts (fn level => fn ctxt =>

    if level = Local_Theory.level lthy then ctxt

    else

      ctxt |> Attrib.local_notes kind

        (Element.transform_facts (Local_Theory.standard_morphism lthy ctxt) local_facts) |> snd));

fun theory_abbrev prmode (b, mx) (t, _) xs =

  Local_Theory.background_theory_result

    (Sign.add_abbrev (#1 prmode) (b, t) #->

      (fn (lhs, _) => Sign.notation true prmode [(lhs, mx)] #> pair lhs))

  #-> (fn lhs => fn lthy' => lthy' |>

        const_declaration (fn level => level <> Local_Theory.level lthy') prmode

          ((b, mx), Term.list_comb (Logic.unvarify_global lhs, xs)));

fun theory_declaration decl =

  background_declaration decl #> standard_declaration (K true) decl;

end;