module Quox.Displace

import Quox.Syntax


parameters (k : Universe)
  namespace Term
    export doDisplace   : Term d n          -> Term d n
    export doDisplaceS  : ScopeTermN s d n  -> ScopeTermN s d n
    export doDisplaceDS : DScopeTermN s d n -> DScopeTermN s d n

  namespace Elim
    export doDisplace : Elim d n -> Elim d n

  namespace Term
    doDisplace (TYPE l loc) = TYPE (k + l) loc
    doDisplace (Pi qty arg res loc) =
      Pi qty (doDisplace arg) (doDisplaceS res) loc
    doDisplace (Lam body loc) = Lam (doDisplaceS body) loc
    doDisplace (Sig fst snd loc) = Sig (doDisplace fst) (doDisplaceS snd) loc
    doDisplace (Pair fst snd loc) = Pair (doDisplace fst) (doDisplace snd) loc
    doDisplace (Enum cases loc) = Enum cases loc
    doDisplace (Tag tag loc) = Tag tag loc
    doDisplace (Eq ty l r loc) =
      Eq (doDisplaceDS ty) (doDisplace l) (doDisplace r) loc
    doDisplace (DLam body loc) = DLam (doDisplaceDS body) loc
    doDisplace (Nat loc) = Nat loc
    doDisplace (Zero loc) = Zero loc
    doDisplace (Succ p loc) = Succ (doDisplace p) loc
    doDisplace (BOX qty ty loc) = BOX qty (doDisplace ty) loc
    doDisplace (Box val loc) = Box (doDisplace val) loc
    doDisplace (E e) = E (doDisplace e)
    doDisplace (CloT (Sub t th)) =
      CloT (Sub (doDisplace t) (map doDisplace th))
    doDisplace (DCloT (Sub t th)) =
      DCloT (Sub (doDisplace t) th)

    doDisplaceS (S names (Y body)) = S names $ Y $ doDisplace body
    doDisplaceS (S names (N body)) = S names $ N $ doDisplace body

    doDisplaceDS (S names (Y body)) = S names $ Y $ doDisplace body
    doDisplaceDS (S names (N body)) = S names $ N $ doDisplace body

  namespace Elim
    doDisplace (F x u loc) = F x (k + u) loc
    doDisplace (B i loc) = B i loc
    doDisplace (App fun arg loc) = App (doDisplace fun) (doDisplace arg) loc
    doDisplace (CasePair qty pair ret body loc) =
      CasePair qty (doDisplace pair) (doDisplaceS ret) (doDisplaceS body) loc
    doDisplace (CaseEnum qty tag ret arms loc) =
      CaseEnum qty (doDisplace tag) (doDisplaceS ret) (map doDisplace arms) loc
    doDisplace (CaseNat qty qtyIH nat ret zero succ loc) =
      CaseNat qty qtyIH (doDisplace nat) (doDisplaceS ret)
              (doDisplace zero) (doDisplaceS succ) loc
    doDisplace (CaseBox qty box ret body loc) =
      CaseBox qty (doDisplace box) (doDisplaceS ret) (doDisplaceS body) loc
    doDisplace (DApp fun arg loc) =
      DApp (doDisplace fun) arg loc
    doDisplace (Ann tm ty loc) =
      Ann (doDisplace tm) (doDisplace ty) loc
    doDisplace (Coe ty p q val loc) =
      Coe (doDisplaceDS ty) p q (doDisplace val) loc
    doDisplace (Comp ty p q val r zero one loc) =
      Comp (doDisplace ty) p q (doDisplace val) r
           (doDisplaceDS zero) (doDisplaceDS one) loc
    doDisplace (TypeCase ty ret arms def loc) =
      TypeCase (doDisplace ty) (doDisplace ret)
               (map doDisplaceS arms) (doDisplace def) loc
    doDisplace (CloE (Sub e th)) =
      CloE (Sub (doDisplace e) (map doDisplace th))
    doDisplace (DCloE (Sub e th)) =
      DCloE (Sub (doDisplace e) th)


namespace Term
  export
  displace : Universe -> Term d n -> Term d n
  displace 0 t = t
  displace u t = doDisplace u t

namespace Elim
  export
  displace : Universe -> Elim d n -> Elim d n
  displace 0 t = t
  displace u t = doDisplace u t