(.module:
  lux
  (lux (control [monad #+ do]
                ["ex" exception #+ exception:]
                ["p" parser])
       (data ["e" error]
             text/format)
       [macro]
       (macro ["s" syntax]))
  (luxc ["&" lang]
        (lang [".L" variable #+ Variable Register]
              [".L" extension]
              ["ls" synthesis]
              (host [python #+ Expression Statement])))
  [//]
  (// [".T" runtime]
      [".T" primitive]
      [".T" structure]
      [".T" function]
      [".T" reference]
      [".T" case]
      [".T" procedure]))

(exception: #export Invalid-Function-Syntax)
(exception: #export Unrecognized-Synthesis)

(def: #export (translate synthesis)
  (-> ls.Synthesis (Meta Expression))
  (case synthesis
    (^code [])
    (:: macro.Monad<Meta> wrap runtimeT.unit)

    (^code [(~ singleton)])
    (translate singleton)

    (^template [<tag> <generator>]
      [_ (<tag> value)]
      (<generator> value))
    ([#.Bool primitiveT.translate-bool]
     [#.Nat  primitiveT.translate-nat]
     [#.Int  primitiveT.translate-int]
     [#.Deg  primitiveT.translate-deg]
     [#.Frac primitiveT.translate-frac]
     [#.Text primitiveT.translate-text])

    (^code ((~ [_ (#.Nat tag)]) (~ [_ (#.Bool last?)]) (~ valueS)))
    (structureT.translate-variant translate tag last? valueS)

    (^code [(~+ members)])
    (structureT.translate-tuple translate members)

    (^ [_ (#.Form (list [_ (#.Int var)]))])
    (referenceT.translate-variable var)

    [_ (#.Symbol definition)]
    (referenceT.translate-definition definition)

    (^code ("lux let" (~ [_ (#.Nat register)]) (~ inputS) (~ exprS)))
    (caseT.translate-let translate register inputS exprS)

    (^code ("lux case" (~ inputS) (~ pathPS)))
    (caseT.translate-case translate inputS pathPS)

    (^code ("lux function" (~ [_ (#.Nat arity)]) [(~+ environment)] (~ bodyS)))
    (case (s.run environment (p.some s.int))
      (#e.Success environment)
      (functionT.translate-function translate environment arity bodyS)

      _
      (&.throw Invalid-Function-Syntax (%code synthesis)))

    (^code ("lux call" (~ functionS) (~+ argsS)))
    (functionT.translate-apply translate functionS argsS)

    (^code ((~ [_ (#.Text procedure)]) (~+ argsS)))
    (procedureT.translate-procedure translate procedure argsS)
    ## (do macro.Monad<Meta>
    ##   [translation (extensionL.find-translation procedure)]
    ##   (translation argsS))

    _
    (&.throw Unrecognized-Synthesis (%code synthesis))))