##  Copyright (c) Eduardo Julian. All rights reserved.
##  This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
##  If a copy of the MPL was not distributed with this file,
##  You can obtain one at http://mozilla.org/MPL/2.0/.

(;import lux
         (lux (meta macro
                    ast)
              (control (functor #as F)
                       (monad #as M)))
         (.. list
             (text #as T #open ("text:" Text/Monoid))))

## [Types]
(deftype #export (IO a)
  (-> (,) a))

## [Syntax]
(defmacro #export (io tokens state)
  (case tokens
    (\ (list value))
    (let [blank (symbol$ ["" ""])]
      (#;Right [state (list (` (_lux_lambda (~ blank) (~ blank) (~ value))))]))

    _
    (#;Left "Wrong syntax for io")))

## [Structures]
(defstruct #export IO/Functor (F;Functor IO)
  (def (F;map f ma)
    (io (f (ma [])))))

(defstruct #export IO/Monad (M;Monad IO)
  (def M;_functor IO/Functor)
  
  (def (M;wrap x)
    (io x))

  (def (M;join mma)
    (mma [])))

## [Functions]
(def #export (print x)
  (-> Text (IO (,)))
  (io (_jvm_invokevirtual "java.io.PrintStream" "print" ["java.lang.Object"]
                          (_jvm_getstatic "java.lang.System" "out") [x])))

(def #export (println x)
  (-> Text (IO (,)))
  (io (_jvm_invokevirtual "java.io.PrintStream" "println" ["java.lang.Object"]
                          (_jvm_getstatic "java.lang.System" "out") [x])))