(*  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, 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), Term.close_schematic_term 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;