(*  Title:      HOL/Import/import_data.ML
    Author:     Cezary Kaliszyk, University of Innsbruck
    Author:     Alexander Krauss, QAware GmbH

Importer data.
*)

signature IMPORT_DATA =
sig
  val get_const_map : string -> theory -> string option
  val get_typ_map : string -> theory -> string option
  val get_const_def : string -> theory -> thm option
  val get_typ_def : string -> theory -> thm option

  val add_const_map : string -> string -> theory -> theory
  val add_const_map_cmd : string -> string -> theory -> theory
  val add_typ_map : string -> string -> theory -> theory
  val add_typ_map_cmd : string -> string -> theory -> theory
  val add_const_def : string -> thm -> string option -> theory -> theory
  val add_typ_def : string -> string -> string -> thm -> theory -> theory
end

structure Import_Data: IMPORT_DATA =
struct

structure Data = Theory_Data
(
  type T = {const_map: string Symtab.table, ty_map: string Symtab.table,
            const_def: thm Symtab.table, ty_def: thm Symtab.table}
  val empty = {const_map = Symtab.empty, ty_map = Symtab.empty,
               const_def = Symtab.empty, ty_def = Symtab.empty}
  fun merge
   ({const_map = cm1, ty_map = tm1, const_def = cd1, ty_def = td1},
    {const_map = cm2, ty_map = tm2, const_def = cd2, ty_def = td2}) : T =
    {const_map = Symtab.merge (K true) (cm1, cm2), ty_map = Symtab.merge (K true) (tm1, tm2),
     const_def = Symtab.merge (K true) (cd1, cd2), ty_def = Symtab.merge (K true) (td1, td2)
    }
)

fun get_const_map s thy = Symtab.lookup (#const_map (Data.get thy)) s

fun get_typ_map s thy = Symtab.lookup (#ty_map (Data.get thy)) s

fun get_const_def s thy = Symtab.lookup (#const_def (Data.get thy)) s

fun get_typ_def s thy = Symtab.lookup (#ty_def (Data.get thy)) s

fun add_const_map s1 s2 thy =
  Data.map (fn {const_map, ty_map, const_def, ty_def} =>
    {const_map = (Symtab.update (s1, s2) const_map), ty_map = ty_map,
     const_def = const_def, ty_def = ty_def}) thy

fun add_const_map_cmd s1 raw_s2 thy =
  let
    val ctxt = Proof_Context.init_global thy
    val Const (s2, _) = Proof_Context.read_const {proper = true, strict = false} ctxt raw_s2
  in add_const_map s1 s2 thy end

fun add_typ_map s1 s2 thy =
  Data.map (fn {const_map, ty_map, const_def, ty_def} =>
    {const_map = const_map, ty_map = (Symtab.update (s1, s2) ty_map),
     const_def = const_def, ty_def = ty_def}) thy

fun add_typ_map_cmd s1 raw_s2 thy =
  let
    val ctxt = Proof_Context.init_global thy
    val Type (s2, _) = Proof_Context.read_type_name {proper = true, strict = false} ctxt raw_s2
  in add_typ_map s1 s2 thy end

fun add_const_def s th name_opt thy =
  let
    val th = Thm.legacy_freezeT th
    val name = case name_opt of
         NONE => (fst o dest_Const o fst o HOLogic.dest_eq o
           HOLogic.dest_Trueprop o Thm.prop_of) th
       | SOME n => n
    val thy' = add_const_map s name thy
  in
    Data.map (fn {const_map, ty_map, const_def, ty_def} =>
      {const_map = const_map, ty_map = ty_map,
       const_def = (Symtab.update (s, th) const_def), ty_def = ty_def}) thy'
  end

fun add_typ_def tyname absname repname th thy =
  let
    val th = Thm.legacy_freezeT th
    val (l, _) = dest_comb (HOLogic.dest_Trueprop (Thm.prop_of th))
    val (l, abst) = dest_comb l
    val (_, rept) = dest_comb l
    val (absn, _) = dest_Const abst
    val (repn, _) = dest_Const rept
    val nty = domain_type (fastype_of rept)
    val ntyn = fst (dest_Type nty)
    val thy2 = add_typ_map tyname ntyn thy
    val thy3 = add_const_map absname absn thy2
    val thy4 = add_const_map repname repn thy3
  in
    Data.map (fn {const_map, ty_map, const_def, ty_def} =>
      {const_map = const_map, ty_map = ty_map,
       const_def = const_def, ty_def = (Symtab.update (tyname, th) ty_def)}) thy4
  end

val _ = Theory.setup
  (Attrib.setup \<^binding>\<open>import_const\<close>
    (Scan.lift Parse.name --
      Scan.option (Scan.lift \<^keyword>\<open>:\<close> |-- Args.const {proper = true, strict = false}) >>
      (fn (s1, s2) => Thm.declaration_attribute
        (fn th => Context.mapping (add_const_def s1 th s2) I)))
  "declare a theorem as an equality that maps the given constant")

val _ = Theory.setup
  (Attrib.setup \<^binding>\<open>import_type\<close>
    (Scan.lift (Parse.name -- Parse.name -- Parse.name) >>
      (fn ((tyname, absname), repname) => Thm.declaration_attribute
        (fn th => Context.mapping (add_typ_def tyname absname repname th) I)))
  "declare a type_definition theorem as a map for an imported type with abs and rep")

val _ =
  Outer_Syntax.command \<^command_keyword>\<open>import_type_map\<close>
    "map external type name to existing Isabelle/HOL type name"
    ((Parse.name --| \<^keyword>\<open>:\<close>) -- Parse.type_const >>
      (fn (ty_name1, ty_name2) => Toplevel.theory (add_typ_map_cmd ty_name1 ty_name2)))

val _ =
  Outer_Syntax.command \<^command_keyword>\<open>import_const_map\<close>
    "map external const name to existing Isabelle/HOL const name"
    ((Parse.name --| \<^keyword>\<open>:\<close>) -- Parse.const >>
      (fn (cname1, cname2) => Toplevel.theory (add_const_map_cmd cname1 cname2)))

(* Initial type and constant maps, for types and constants that are not
   defined, which means their definitions do not appear in the proof dump *)
val _ = Theory.setup
  (add_typ_map "bool" \<^type_name>\<open>bool\<close> #>
  add_typ_map "fun" \<^type_name>\<open>fun\<close> #>
  add_typ_map "ind" \<^type_name>\<open>ind\<close> #>
  add_const_map "=" \<^const_name>\<open>HOL.eq\<close> #>
  add_const_map "@" \<^const_name>\<open>Eps\<close>)

end
