(*  Title:      Pure/Isar/theory_target.ML

    Author:     Makarius

    Author:     Florian Haftmann, TU Muenchen

Targets for theory, locale and class.

*)

signature NAMED_TARGET =

sig

  val peek: local_theory -> {target: string, is_locale: bool, is_class: bool}

  val init: string option -> theory -> local_theory

  val context_cmd: xstring -> theory -> local_theory

end;

structure Named_Target: NAMED_TARGET =

struct

(* context data *)

datatype target = Target of {target: string, is_locale: bool, is_class: bool};

fun make_target target is_locale is_class =

  Target {target = target, is_locale = is_locale, is_class = is_class};

val global_target = make_target "" false false;

structure Data = Proof_Data

(

  type T = target;

  fun init _ = global_target;

);

val peek = (fn Target args => args) o Data.get;

(* generic declarations *)

fun locale_declaration locale { syntax, pervasive } decl lthy =

  let

    val add = if syntax then Locale.add_syntax_declaration else Locale.add_declaration;

    val locale_decl = Morphism.transform (Local_Theory.target_morphism lthy) decl;

  in

    lthy

    |> pervasive ? Generic_Target.theory_declaration decl

    |> Local_Theory.target (add locale locale_decl)

  end;

fun target_declaration (Target {target, ...}) { syntax, pervasive } =

  if target = "" then Generic_Target.theory_declaration

  else locale_declaration target { syntax = syntax, pervasive = pervasive };

(* consts in locales *)

fun locale_const (Target {target, is_class, ...}) (prmode as (mode, _)) ((b, mx), rhs) phi =

  let

    val b' = Morphism.binding phi b;

    val rhs' = Morphism.term phi rhs;

    val arg = (b', Term.close_schematic_term rhs');

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

    (* FIXME workaround based on educated guess *)

    val prefix' = Binding.prefix_of b';

    val is_canonical_class = is_class andalso

      (Binding.eq_name (b, b')

        andalso not (null prefix')

        andalso List.last prefix' = (Class_Target.class_prefix target, false)

      orelse same_shape);

  in

    not is_canonical_class ?

      (Context.mapping_result

        (Sign.add_abbrev Print_Mode.internal arg)

        (ProofContext.add_abbrev Print_Mode.internal arg)

      #-> (fn (lhs' as Const (d, _), _) =>

          same_shape ?

            (Context.mapping

              (Sign.revert_abbrev mode d) (ProofContext.revert_abbrev mode d) #>

             Morphism.form (ProofContext.target_notation true prmode [(lhs', mx)]))))

  end;

fun locale_const_declaration (ta as Target {target, ...}) prmode arg =

  locale_declaration target { syntax = true, pervasive = false } (locale_const ta prmode arg);

fun class_target (Target {target, ...}) f =

  Local_Theory.raw_theory f #>

  Local_Theory.target (Class_Target.refresh_syntax target);

(* define *)

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

  Generic_Target.theory_foundation (((b, U), NoSyn), (b_def, rhs)) (type_params, term_params)

  #-> (fn (lhs, def) => locale_const_declaration ta Syntax.mode_default ((b, mx), lhs)

    #> pair (lhs, def))

fun class_foundation (ta as Target {target, ...})

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

  Generic_Target.theory_foundation (((b, U), NoSyn), (b_def, rhs)) (type_params, term_params)

  #-> (fn (lhs, def) => locale_const_declaration ta Syntax.mode_default ((b, NoSyn), lhs)

    #> class_target ta (Class_Target.declare target ((b, mx), (type_params, lhs)))

    #> pair (lhs, def))

fun target_foundation (ta as Target {target, is_locale, is_class, ...}) =

  if is_class then class_foundation ta

  else if is_locale then locale_foundation ta

  else Generic_Target.theory_foundation;

(* notes *)

fun locale_notes locale kind global_facts local_facts lthy = 

  let

    val global_facts' = Attrib.map_facts (K I) global_facts;

    val local_facts' = Element.facts_map

      (Element.morph_ctxt (Local_Theory.target_morphism lthy)) local_facts;

  in

    lthy

    |> Local_Theory.theory (PureThy.note_thmss kind global_facts' #> snd)

    |> Local_Theory.target (Locale.add_thmss locale kind local_facts')

  end

fun target_notes (ta as Target {target, is_locale, ...}) =

  if is_locale then locale_notes target

    else fn kind => fn global_facts => fn _ => Generic_Target.theory_notes kind global_facts;

(* abbrev *)

fun locale_abbrev ta prmode ((b, mx), t) xs = Local_Theory.theory_result

  (Sign.add_abbrev Print_Mode.internal (b, t)) #->

    (fn (lhs, _) => locale_const_declaration ta prmode

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

fun target_abbrev (ta as Target {target, is_locale, is_class, ...})

    prmode (b, mx) (global_rhs, t') xs lthy =

  if is_locale

    then lthy

      |> locale_abbrev ta prmode ((b, if is_class then NoSyn else mx), global_rhs) xs

      |> is_class ? class_target ta (Class_Target.abbrev target prmode ((b, mx), t'))

    else lthy

      |> Generic_Target.theory_abbrev prmode ((b, mx), global_rhs);

(* pretty *)

fun pretty_thy ctxt target is_class =

  let

    val thy = ProofContext.theory_of ctxt;

    val target_name =

      [Pretty.command (if is_class then "class" else "locale"),

        Pretty.str (" " ^ Locale.extern thy target)];

    val fixes = map (fn (x, T) => (Binding.name x, SOME T, NoSyn))

      (#1 (ProofContext.inferred_fixes ctxt));

    val assumes = map (fn A => (Attrib.empty_binding, [(Thm.term_of A, [])]))

      (Assumption.all_assms_of ctxt);

    val elems =

      (if null fixes then [] else [Element.Fixes fixes]) @

      (if null assumes then [] else [Element.Assumes assumes]);

  in

    if target = "" then []

    else if null elems then [Pretty.block target_name]

    else [Pretty.block (Pretty.fbreaks (Pretty.block (target_name @ [Pretty.str " ="]) ::

      map (Pretty.chunks o Element.pretty_ctxt ctxt) elems))]

  end;

fun pretty (Target {target, is_class, ...}) ctxt =

  Pretty.block [Pretty.command "theory", Pretty.brk 1,

      Pretty.str (Context.theory_name (ProofContext.theory_of ctxt))] ::

    pretty_thy ctxt target is_class;

(* init various targets *)

local

fun init_data (Target {target, is_locale, is_class}) =

  if not is_locale then ProofContext.init_global

  else if not is_class then Locale.init target

  else Class_Target.init target;

fun init_target (ta as Target {target, ...}) thy =

  thy

  |> init_data ta

  |> Data.put ta

  |> Local_Theory.init NONE (Long_Name.base_name target)

     {define = Generic_Target.define (target_foundation ta),

      notes = Generic_Target.notes (target_notes ta),

      abbrev = Generic_Target.abbrev (target_abbrev ta),

      declaration = fn pervasive => target_declaration ta

        { syntax = false, pervasive = pervasive },

      syntax_declaration = fn pervasive => target_declaration ta

        { syntax = true, pervasive = pervasive },

      pretty = pretty ta,

      reinit = init_target ta o ProofContext.theory_of,

      exit = Local_Theory.target_of};

fun named_target _ NONE = global_target

  | named_target thy (SOME target) =

      if Locale.defined thy target

      then make_target target true (Class_Target.is_class thy target)

      else error ("No such locale: " ^ quote target);

in

fun init target thy = init_target (named_target thy target) thy;

fun context_cmd "-" thy = init NONE thy

  | context_cmd target thy = init (SOME (Locale.intern thy target)) thy;

end;

end;