(*  Title:      nominal_dt_alpha.ML
    Author:     Christian Urban
    Author:     Cezary Kaliszyk

  Performing quotient constructions
*)

signature NOMINAL_DT_QUOT =
sig
  val qtype_defs: (string list * binding * mixfix) list -> typ list -> term list -> 
    thm list -> local_theory -> Quotient_Info.quotdata_info list * local_theory

  val qconst_defs: typ list -> (string  * term * mixfix) list -> local_theory -> 
    Quotient_Info.qconsts_info list * local_theory

  val qperm_defs: typ list -> string list -> (string * term * mixfix) list -> 
    thm list -> theory -> theory
end

structure Nominal_Dt_Quot: NOMINAL_DT_QUOT =
struct

(* defines the quotient types *)
fun qtype_defs qtys_descr alpha_tys alpha_trms alpha_equivp_thms lthy =
let
  val qty_args1 = map2 (fn ty => fn trm => (ty, trm, false)) alpha_tys alpha_trms
  val qty_args2 = (qtys_descr ~~ qty_args1) ~~ alpha_equivp_thms
in
  fold_map Quotient_Type.add_quotient_type qty_args2 lthy
end 


(* defines quotient constants *)
fun qconst_defs qtys consts_specs lthy =
let
  val (qconst_infos, lthy') = 
    fold_map (Quotient_Def.lift_raw_const qtys) consts_specs lthy
  val phi = ProofContext.export_morphism lthy' lthy
in
  (map (Quotient_Info.transform_qconsts phi) qconst_infos, lthy')
end


(* defines the quotient permutations *)
fun qperm_defs qtys full_tnames name_term_pairs thms thy =
let
  val lthy =
    Theory_Target.instantiation (full_tnames, [], @{sort pt}) thy;
  val (_, lthy') = qconst_defs qtys name_term_pairs lthy;
  val lifted_thms = map (Quotient_Tacs.lifted qtys lthy') thms;
  fun tac _ =
    Class.intro_classes_tac [] THEN
    (ALLGOALS (resolve_tac lifted_thms))
  val lthy'' = Class.prove_instantiation_instance tac lthy'
in
  Local_Theory.exit_global lthy''
end


end (* structure *)