Add Show Unit instance

Add Show Unit instance

module Prelude
  ( flip
  , const
  , asTypeOf
  , Semigroupoid, (<<<), (>>>)
  , Category, id
  , ($), (#)
  , (:), cons
  , Show, show
  , Functor, (<$>)
  , Apply, (<*>)
  , Applicative, pure, liftA1
  , Alternative, empty, (<|>)
  , Bind, (>>=)
  , Monad, return, liftM1, ap
  , Num, (+), (-), (*), (/), (%)
  , negate
  , Eq, (==), (/=), refEq, refIneq
  , Ord, Ordering(..), compare, (<), (>), (<=), (>=)
  , Bits, (&), (|), (^), shl, shr, zshr, complement
  , BoolLike, (&&), (||)
  , not
  , Semigroup, (<>), (++)
  , Unit(..)
  ) where

  flip :: forall a b c. (a -> b -> c) -> b -> a -> c
  flip f b a = f a b

  const :: forall a b. a -> b -> a
  const a _ = a

  asTypeOf :: forall a. a -> a -> a
  asTypeOf x _ = x

  infixr 9 >>>
  infixr 9 <<<

  class Semigroupoid a where
    (<<<) :: forall b c d. a c d -> a b c -> a b d

  instance semigroupoidArr :: Semigroupoid (->) where
    (<<<) f g x = f (g x)

  (>>>) :: forall a b c d. (Semigroupoid a) => a b c -> a c d -> a b d
  (>>>) f g = g <<< f

  class (Semigroupoid a) <= Category a where
    id :: forall t. a t t

  instance categoryArr :: Category (->) where
    id x = x

  infixr 0 $
  infixl 0 #

  ($) :: forall a b. (a -> b) -> a -> b
  ($) f x = f x

  (#) :: forall a b. a -> (a -> b) -> b
  (#) x f = f x

  infixr 6 :

  (:) :: forall a. a -> [a] -> [a]
  (:) = cons

  foreign import cons
    "function cons(e) {\
    \  return function (l) {\
    \    return [e].concat(l);\
    \  };\
    \}" :: forall a. a -> [a] -> [a]

  class Show a where
    show :: a -> String

  foreign import showStringImpl
    "function showStringImpl(s) {\
    \  return JSON.stringify(s);\
    \}" :: String -> String

  instance showUnit :: Show Unit where
    show (Unit {}) = "Unit {}"

  instance showString :: Show String where
    show = showStringImpl

  instance showBoolean :: Show Boolean where
    show true = "true"
    show false = "false"

  foreign import showNumberImpl "function showNumberImpl(n) {\
                                \  return n.toString();\
                                \}" :: Number -> String

  instance showNumber :: Show Number where
    show = showNumberImpl

  foreign import showArrayImpl
    "function showArrayImpl (f) {\
    \  return function (xs) {\
    \    var ss = [];\
    \    for (var i = 0, l = xs.length; i < l; i++) {\
    \      ss[i] = f(xs[i]);\
    \    }\
    \    return '[' + ss.join(',') + ']';\
    \  };\
    \}" :: forall a. (a -> String) -> [a] -> String

  instance showArray :: (Show a) => Show [a] where
    show = showArrayImpl show

  infixl 4 <$>

  class Functor f where
    (<$>) :: forall a b. (a -> b) -> f a -> f b

  infixl 4 <*>

  class (Functor f) <= Apply f where
    (<*>) :: forall a b. f (a -> b) -> f a -> f b

  class (Apply f) <= Applicative f where
    pure :: forall a. a -> f a

  liftA1 :: forall f a b. (Applicative f) => (a -> b) -> f a -> f b
  liftA1 f a = pure f <*> a

  infixl 3 <|>

  class Alternative f where
    empty :: forall a. f a
    (<|>) :: forall a. f a -> f a -> f a

  infixl 1 >>=

  class (Apply m) <= Bind m where
    (>>=) :: forall a b. m a -> (a -> m b) -> m b

  class (Applicative m, Bind m) <= Monad m

  return :: forall m a. (Monad m) => a -> m a
  return = pure

  liftM1 :: forall m a b. (Monad m) => (a -> b) -> m a -> m b
  liftM1 f a = do
    a' <- a
    return (f a')

  ap :: forall m a b. (Monad m) => m (a -> b) -> m a -> m b
  ap f a = do
    f' <- f
    a' <- a
    return (f' a')

  infixl 7 *
  infixl 7 /
  infixl 7 %

  infixl 6 -
  infixl 6 +

  class Num a where
    (+) :: a -> a -> a
    (-) :: a -> a -> a
    (*) :: a -> a -> a
    (/) :: a -> a -> a
    (%) :: a -> a -> a
    negate :: a -> a

  foreign import numAdd "function numAdd(n1) {\
                        \  return function(n2) {\
                        \    return n1 + n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numSub "function numSub(n1) {\
                        \  return function(n2) {\
                        \    return n1 - n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numMul "function numMul(n1) {\
                        \  return function(n2) {\
                        \    return n1 * n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numDiv "function numDiv(n1) {\
                        \  return function(n2) {\
                        \    return n1 / n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numMod "function numMod(n1) {\
                        \  return function(n2) {\
                        \    return n1 % n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numNegate "function numNegate(n) {\
                           \  return -n;\
                           \}" :: Number -> Number

  instance numNumber :: Num Number where
    (+) = numAdd
    (-) = numSub
    (*) = numMul
    (/) = numDiv
    (%) = numMod
    negate = numNegate

  data Unit = Unit {}

  infix 4 ==
  infix 4 /=

  class Eq a where
    (==) :: a -> a -> Boolean
    (/=) :: a -> a -> Boolean

  foreign import refEq
    "function refEq(r1) {\
    \  return function(r2) {\
    \    return r1 === r2;\
    \  };\
    \}" :: forall a. a -> a -> Boolean

  foreign import refIneq
    "function refIneq(r1) {\
    \  return function(r2) {\
    \    return r1 !== r2;\
    \  };\
    \}" :: forall a. a -> a -> Boolean

  instance eqUnit :: Eq Unit where
    (==) (Unit {}) (Unit {}) = true
    (/=) (Unit {}) (Unit {}) = false

  instance eqString :: Eq String where
    (==) = refEq
    (/=) = refIneq

  instance eqNumber :: Eq Number where
    (==) = refEq
    (/=) = refIneq

  instance eqBoolean :: Eq Boolean where
    (==) = refEq
    (/=) = refIneq

  instance eqArray :: (Eq a) => Eq [a] where
    (==) [] [] = true
    (==) (x:xs) (y:ys) = x == y && xs == ys
    (==) _ _ = false
    (/=) xs ys = not (xs == ys)

  data Ordering = LT | GT | EQ

  instance eqOrdering :: Eq Ordering where
    (==) LT LT = true
    (==) GT GT = true
    (==) EQ EQ = true
    (==) _  _  = false
    (/=) x y = not (x == y)

  instance showOrdering :: Show Ordering where
    show LT = "LT"
    show GT = "GT"
    show EQ = "EQ"

  class (Eq a) <= Ord a where
    compare :: a -> a -> Ordering

  infixl 4 <

  (<) :: forall a. (Ord a) => a -> a -> Boolean
  (<) a1 a2 = case a1 `compare` a2 of
    LT -> true
    _ -> false

  infixl 4 >

  (>) :: forall a. (Ord a) => a -> a -> Boolean
  (>) a1 a2 = case a1 `compare` a2 of
    GT -> true
    _ -> false

  infixl 4 <=

  (<=) :: forall a. (Ord a) => a -> a -> Boolean
  (<=) a1 a2 = case a1 `compare` a2 of
    GT -> false
    _ -> true

  infixl 4 >=

  (>=) :: forall a. (Ord a) => a -> a -> Boolean
  (>=) a1 a2 = case a1 `compare` a2 of
    LT -> false
    _ -> true

  foreign import unsafeCompare
    "function unsafeCompare(n1) {\
    \  return function(n2) {\
    \    return n1 < n2 ? LT : n1 > n2 ? GT : EQ;\
    \  };\
    \}" :: forall a. a -> a -> Ordering

  instance ordUnit :: Ord Unit where
    compare (Unit {}) (Unit {}) = EQ

  instance ordBoolean :: Ord Boolean where
    compare false false = EQ
    compare false true  = LT
    compare true  true  = EQ
    compare true  false = GT

  instance ordNumber :: Ord Number where
    compare = unsafeCompare

  instance ordString :: Ord String where
    compare = unsafeCompare

  instance ordArray :: (Ord a) => Ord [a] where
    compare [] [] = EQ
    compare [] _ = LT
    compare _ [] = GT
    compare (x:xs) (y:ys) = case compare x y of
      EQ -> compare xs ys
      other -> other

  infixl 10 &
  infixl 10 |
  infixl 10 ^

  class Bits b where
    (&) :: b -> b -> b
    (|) :: b -> b -> b
    (^) :: b -> b -> b
    shl :: b -> Number -> b
    shr :: b -> Number -> b
    zshr :: b -> Number -> b
    complement :: b -> b

  foreign import numShl "function numShl(n1) {\
                        \  return function(n2) {\
                        \    return n1 << n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numShr "function numShr(n1) {\
                        \  return function(n2) {\
                        \    return n1 >> n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numZshr "function numZshr(n1) {\
                          \  return function(n2) {\
                          \    return n1 >>> n2;\
                          \  };\
                          \}" :: Number -> Number -> Number

  foreign import numAnd "function numAnd(n1) {\
                        \  return function(n2) {\
                        \    return n1 & n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numOr "function numOr(n1) {\
                       \  return function(n2) {\
                       \    return n1 | n2;\
                       \  };\
                       \}" :: Number -> Number -> Number

  foreign import numXor "function numXor(n1) {\
                        \  return function(n2) {\
                        \    return n1 ^ n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numComplement "function numComplement(n) {\
                               \  return ~n;\
                               \}" :: Number -> Number

  instance bitsNumber :: Bits Number where
    (&) = numAnd
    (|) = numOr
    (^) = numXor
    shl = numShl
    shr = numShr
    zshr = numZshr
    complement = numComplement

  infixr 2 ||
  infixr 3 &&

  class BoolLike b where
    (&&) :: b -> b -> b
    (||) :: b -> b -> b
    not :: b -> b

  foreign import boolAnd "function boolAnd(b1) {\
                         \  return function(b2) {\
                         \    return b1 && b2;\
                         \  };\
                         \}"  :: Boolean -> Boolean -> Boolean

  foreign import boolOr "function boolOr(b1) {\
                        \  return function(b2) {\
                        \    return b1 || b2;\
                        \  };\
                        \}" :: Boolean -> Boolean -> Boolean

  foreign import boolNot "function boolNot(b) {\
                         \  return !b;\
                         \}" :: Boolean -> Boolean

  instance boolLikeBoolean :: BoolLike Boolean where
    (&&) = boolAnd
    (||) = boolOr
    not = boolNot

  infixr 5 <>

  class Semigroup a where
    (<>) :: a -> a -> a

  foreign import concatString
    "function concatString(s1) {\
    \  return function(s2) {\
    \    return s1 + s2;\
    \  };\
    \}" :: String -> String -> String

  instance semigroupUnit :: Semigroup Unit where
    (<>) (Unit {}) (Unit {}) = Unit {}

  instance semigroupString :: Semigroup String where
    (<>) = concatString

  infixr 5 ++

  (++) :: forall s. (Semigroup s) => s -> s -> s
  (++) = (<>)

module Data.Function where

  on :: forall a b c. (b -> b -> c) -> (a -> b) -> a -> a -> c
  on f g x y = g x `f` g y

module Data.Eq where

  data Ref a = Ref a

  liftRef :: forall a b. (a -> a -> b) -> Ref a -> Ref a -> b
  liftRef f (Ref x) (Ref y) = f x y

  instance eqRef :: Eq (Ref a) where
    (==) = liftRef refEq
    (/=) = liftRef refIneq

module Prelude.Unsafe where

  foreign import unsafeIndex
    "function unsafeIndex(xs) {\
    \  return function(n) {\
    \    return xs[n];\
    \  };\
    \}" :: forall a. [a] -> Number -> a

module Control.Monad.Eff where

  foreign import data Eff :: # ! -> * -> *

  foreign import returnE "function returnE(a) {\
                         \  return function() {\
                         \    return a;\
                         \  };\
                         \}" :: forall e a. a -> Eff e a

  foreign import bindE "function bindE(a) {\
                       \  return function(f) {\
                       \    return function() {\
                       \      return f(a())();\
                       \    };\
                       \  };\
                       \}" :: forall e a b. Eff e a -> (a -> Eff e b) -> Eff e b

  type Pure a = forall e. Eff e a

  foreign import runPure "function runPure(f) {\
                         \  return f();\
                         \}" :: forall a. Pure a -> a

  instance functorEff :: Functor (Eff e) where
    (<$>) = liftA1

  instance applyEff :: Apply (Eff e) where
    (<*>) = ap

  instance applicativeEff :: Applicative (Eff e) where
    pure = returnE

  instance bindEff :: Bind (Eff e) where
    (>>=) = bindE

  instance monadEff :: Monad (Eff e)

  foreign import untilE "function untilE(f) {\
                        \  return function() {\
                        \    while (!f()) { }\
                        \    return {};\
                        \  };\
                        \}" :: forall e. Eff e Boolean -> Eff e {}

  foreign import whileE "function whileE(f) {\
                        \  return function(a) {\
                        \    return function() {\
                        \      while (f()) {\
                        \        a();\
                        \      }\
                        \      return {};\
                        \    };\
                        \  };\
                        \}" :: forall e a. Eff e Boolean -> Eff e a -> Eff e {}

  foreign import forE "function forE(lo) {\
                      \  return function(hi) {\
                      \    return function(f) {\
                      \      return function() {\
                      \        for (var i = lo; i < hi; i++) {\
                      \          f(i)();\
                      \        }\
                      \      };\
                      \    };\
                      \  };\
                      \}" :: forall e. Number -> Number -> (Number -> Eff e {}) -> Eff e {}

  foreign import foreachE "function foreachE(as) {\
                          \  return function(f) {\
                          \    for (var i = 0; i < as.length; i++) {\
                          \      f(as[i])();\
                          \    }\
                          \  };\
                          \}" :: forall e a. [a] -> (a -> Eff e {}) -> Eff e {}

module Control.Monad.Eff.Unsafe where

  import Control.Monad.Eff

  foreign import unsafeInterleaveEff
    "function unsafeInterleaveEff(f) {\
    \  return f;\
    \}" :: forall eff1 eff2 a. Eff eff1 a -> Eff eff2 a

module Debug.Trace where

  import Control.Monad.Eff

  foreign import data Trace :: !

  foreign import trace "function trace(s) {\
                       \  return function() {\
                       \    console.log(s);\
                       \    return {};\
                       \  };\
                       \}" :: forall r. String -> Eff (trace :: Trace | r) {}

  print :: forall a r. (Show a) => a -> Eff (trace :: Trace | r) {}
  print o = trace (show o)

module Control.Monad.ST where

  import Control.Monad.Eff

  foreign import data ST :: * -> !

  foreign import data STRef :: * -> * -> *

  foreign import data STArray :: * -> * -> *

  foreign import newSTRef "function newSTRef(val) {\
                          \  return function () {\
                          \    return { value: val };\
                          \  };\
                          \}" :: forall a h r. a -> Eff (st :: ST h | r) (STRef h a)

  foreign import readSTRef "function readSTRef(ref) {\
                           \  return function() {\
                           \    return ref.value;\
                           \  };\
                           \}" :: forall a h r. STRef h a -> Eff (st :: ST h | r) a

  foreign import modifySTRef "function modifySTRef(ref) {\
                             \  return function(f) {\
                             \    return function() {\
                             \      return ref.value = f(ref.value);\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STRef h a -> (a -> a) -> Eff (st :: ST h | r) a

  foreign import writeSTRef "function writeSTRef(ref) {\
                            \  return function(a) {\
                            \    return function() {\
                            \      return ref.value = a;\
                            \    };\
                            \  };\
                            \}" :: forall a h r. STRef h a -> a -> Eff (st :: ST h | r) a

  foreign import newSTArray "function newSTArray(len) {\
                            \  return function(a) {\
                            \    return function() {\
                            \      var arr = [];\
                            \      for (var i = 0; i < len; i++) {\
                            \        arr[i] = a;\
                            \      };\
                            \      return arr;\
                            \    };\
                            \  };\
                            \}" :: forall a h r. Number -> a -> Eff (st :: ST h | r) (STArray h a)

  foreign import peekSTArray "function peekSTArray(arr) {\
                             \  return function(i) {\
                             \    return function() {\
                             \      return arr[i];\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STArray h a -> Eff (st :: ST h | r) a

  foreign import pokeSTArray "function pokeSTArray(arr) {\
                             \  return function(i) {\
                             \    return function(a) {\
                             \      return function() {\
                             \        return arr[i] = a;\
                             \      };\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STArray h a -> Number -> a -> Eff (st :: ST h | r) a

  foreign import runST "function runST(f) {\
                       \  return f;\
                       \}" :: forall a r. (forall h. Eff (st :: ST h | r) a) -> Eff r a

  foreign import runSTArray "function runSTArray(f) {\
                            \  return f;\
                            \}" :: forall a r. (forall h. Eff (st :: ST h | r) (STArray h a)) -> Eff r [a]

module Prelude
  ( flip
  , const
  , asTypeOf
  , Semigroupoid, (<<<), (>>>)
  , Category, id
  , ($), (#)
  , (:), cons
  , Show, show
  , Functor, (<$>)
  , Apply, (<*>)
  , Applicative, pure, liftA1
  , Alternative, empty, (<|>)
  , Bind, (>>=)
  , Monad, return, liftM1, ap
  , Num, (+), (-), (*), (/), (%)
  , negate
  , Eq, (==), (/=), refEq, refIneq
  , Ord, Ordering(..), compare, (<), (>), (<=), (>=)
  , Bits, (&), (|), (^), shl, shr, zshr, complement
  , BoolLike, (&&), (||)
  , not
  , Semigroup, (<>), (++)
  , Unit(..)
  ) where

  flip :: forall a b c. (a -> b -> c) -> b -> a -> c
  flip f b a = f a b

  const :: forall a b. a -> b -> a
  const a _ = a

  asTypeOf :: forall a. a -> a -> a
  asTypeOf x _ = x

  infixr 9 >>>
  infixr 9 <<<

  class Semigroupoid a where
    (<<<) :: forall b c d. a c d -> a b c -> a b d

  instance semigroupoidArr :: Semigroupoid (->) where
    (<<<) f g x = f (g x)

  (>>>) :: forall a b c d. (Semigroupoid a) => a b c -> a c d -> a b d
  (>>>) f g = g <<< f

  class (Semigroupoid a) <= Category a where
    id :: forall t. a t t

  instance categoryArr :: Category (->) where
    id x = x

  infixr 0 $
  infixl 0 #

  ($) :: forall a b. (a -> b) -> a -> b
  ($) f x = f x

  (#) :: forall a b. a -> (a -> b) -> b
  (#) x f = f x

  infixr 6 :

  (:) :: forall a. a -> [a] -> [a]
  (:) = cons

  foreign import cons
    "function cons(e) {\
    \  return function (l) {\
    \    return [e].concat(l);\
    \  };\
    \}" :: forall a. a -> [a] -> [a]

  class Show a where
    show :: a -> String

  foreign import showStringImpl
    "function showStringImpl(s) {\
    \  return JSON.stringify(s);\
    \}" :: String -> String

  instance showString :: Show String where
    show = showStringImpl

  instance showBoolean :: Show Boolean where
    show true = "true"
    show false = "false"

  foreign import showNumberImpl "function showNumberImpl(n) {\
                                \  return n.toString();\
                                \}" :: Number -> String

  instance showNumber :: Show Number where
    show = showNumberImpl

  foreign import showArrayImpl
    "function showArrayImpl (f) {\
    \  return function (xs) {\
    \    var ss = [];\
    \    for (var i = 0, l = xs.length; i < l; i++) {\
    \      ss[i] = f(xs[i]);\
    \    }\
    \    return '[' + ss.join(',') + ']';\
    \  };\
    \}" :: forall a. (a -> String) -> [a] -> String

  instance showArray :: (Show a) => Show [a] where
    show = showArrayImpl show

  infixl 4 <$>

  class Functor f where
    (<$>) :: forall a b. (a -> b) -> f a -> f b

  infixl 4 <*>

  class (Functor f) <= Apply f where
    (<*>) :: forall a b. f (a -> b) -> f a -> f b

  class (Apply f) <= Applicative f where
    pure :: forall a. a -> f a

  liftA1 :: forall f a b. (Applicative f) => (a -> b) -> f a -> f b
  liftA1 f a = pure f <*> a

  infixl 3 <|>

  class Alternative f where
    empty :: forall a. f a
    (<|>) :: forall a. f a -> f a -> f a

  infixl 1 >>=

  class (Apply m) <= Bind m where
    (>>=) :: forall a b. m a -> (a -> m b) -> m b

  class (Applicative m, Bind m) <= Monad m

  return :: forall m a. (Monad m) => a -> m a
  return = pure

  liftM1 :: forall m a b. (Monad m) => (a -> b) -> m a -> m b
  liftM1 f a = do
    a' <- a
    return (f a')

  ap :: forall m a b. (Monad m) => m (a -> b) -> m a -> m b
  ap f a = do
    f' <- f
    a' <- a
    return (f' a')

  infixl 7 *
  infixl 7 /
  infixl 7 %

  infixl 6 -
  infixl 6 +

  class Num a where
    (+) :: a -> a -> a
    (-) :: a -> a -> a
    (*) :: a -> a -> a
    (/) :: a -> a -> a
    (%) :: a -> a -> a
    negate :: a -> a

  foreign import numAdd "function numAdd(n1) {\
                        \  return function(n2) {\
                        \    return n1 + n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numSub "function numSub(n1) {\
                        \  return function(n2) {\
                        \    return n1 - n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numMul "function numMul(n1) {\
                        \  return function(n2) {\
                        \    return n1 * n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numDiv "function numDiv(n1) {\
                        \  return function(n2) {\
                        \    return n1 / n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numMod "function numMod(n1) {\
                        \  return function(n2) {\
                        \    return n1 % n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numNegate "function numNegate(n) {\
                           \  return -n;\
                           \}" :: Number -> Number

  instance numNumber :: Num Number where
    (+) = numAdd
    (-) = numSub
    (*) = numMul
    (/) = numDiv
    (%) = numMod
    negate = numNegate

  data Unit = Unit {}

  infix 4 ==
  infix 4 /=

  class Eq a where
    (==) :: a -> a -> Boolean
    (/=) :: a -> a -> Boolean

  foreign import refEq
    "function refEq(r1) {\
    \  return function(r2) {\
    \    return r1 === r2;\
    \  };\
    \}" :: forall a. a -> a -> Boolean

  foreign import refIneq
    "function refIneq(r1) {\
    \  return function(r2) {\
    \    return r1 !== r2;\
    \  };\
    \}" :: forall a. a -> a -> Boolean

  instance eqUnit :: Eq Unit where
    (==) (Unit {}) (Unit {}) = true
    (/=) (Unit {}) (Unit {}) = false

  instance eqString :: Eq String where
    (==) = refEq
    (/=) = refIneq

  instance eqNumber :: Eq Number where
    (==) = refEq
    (/=) = refIneq

  instance eqBoolean :: Eq Boolean where
    (==) = refEq
    (/=) = refIneq

  instance eqArray :: (Eq a) => Eq [a] where
    (==) [] [] = true
    (==) (x:xs) (y:ys) = x == y && xs == ys
    (==) _ _ = false
    (/=) xs ys = not (xs == ys)

  data Ordering = LT | GT | EQ

  instance eqOrdering :: Eq Ordering where
    (==) LT LT = true
    (==) GT GT = true
    (==) EQ EQ = true
    (==) _  _  = false
    (/=) x y = not (x == y)

  instance showOrdering :: Show Ordering where
    show LT = "LT"
    show GT = "GT"
    show EQ = "EQ"

  class (Eq a) <= Ord a where
    compare :: a -> a -> Ordering

  infixl 4 <

  (<) :: forall a. (Ord a) => a -> a -> Boolean
  (<) a1 a2 = case a1 `compare` a2 of
    LT -> true
    _ -> false

  infixl 4 >

  (>) :: forall a. (Ord a) => a -> a -> Boolean
  (>) a1 a2 = case a1 `compare` a2 of
    GT -> true
    _ -> false

  infixl 4 <=

  (<=) :: forall a. (Ord a) => a -> a -> Boolean
  (<=) a1 a2 = case a1 `compare` a2 of
    GT -> false
    _ -> true

  infixl 4 >=

  (>=) :: forall a. (Ord a) => a -> a -> Boolean
  (>=) a1 a2 = case a1 `compare` a2 of
    LT -> false
    _ -> true

  foreign import unsafeCompare
    "function unsafeCompare(n1) {\
    \  return function(n2) {\
    \    return n1 < n2 ? LT : n1 > n2 ? GT : EQ;\
    \  };\
    \}" :: forall a. a -> a -> Ordering

  instance ordUnit :: Ord Unit where
    compare (Unit {}) (Unit {}) = EQ

  instance ordBoolean :: Ord Boolean where
    compare false false = EQ
    compare false true  = LT
    compare true  true  = EQ
    compare true  false = GT

  instance ordNumber :: Ord Number where
    compare = unsafeCompare

  instance ordString :: Ord String where
    compare = unsafeCompare

  instance ordArray :: (Ord a) => Ord [a] where
    compare [] [] = EQ
    compare [] _ = LT
    compare _ [] = GT
    compare (x:xs) (y:ys) = case compare x y of
      EQ -> compare xs ys
      other -> other

  infixl 10 &
  infixl 10 |
  infixl 10 ^

  class Bits b where
    (&) :: b -> b -> b
    (|) :: b -> b -> b
    (^) :: b -> b -> b
    shl :: b -> Number -> b
    shr :: b -> Number -> b
    zshr :: b -> Number -> b
    complement :: b -> b

  foreign import numShl "function numShl(n1) {\
                        \  return function(n2) {\
                        \    return n1 << n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numShr "function numShr(n1) {\
                        \  return function(n2) {\
                        \    return n1 >> n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numZshr "function numZshr(n1) {\
                          \  return function(n2) {\
                          \    return n1 >>> n2;\
                          \  };\
                          \}" :: Number -> Number -> Number

  foreign import numAnd "function numAnd(n1) {\
                        \  return function(n2) {\
                        \    return n1 & n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numOr "function numOr(n1) {\
                       \  return function(n2) {\
                       \    return n1 | n2;\
                       \  };\
                       \}" :: Number -> Number -> Number

  foreign import numXor "function numXor(n1) {\
                        \  return function(n2) {\
                        \    return n1 ^ n2;\
                        \  };\
                        \}" :: Number -> Number -> Number

  foreign import numComplement "function numComplement(n) {\
                               \  return ~n;\
                               \}" :: Number -> Number

  instance bitsNumber :: Bits Number where
    (&) = numAnd
    (|) = numOr
    (^) = numXor
    shl = numShl
    shr = numShr
    zshr = numZshr
    complement = numComplement

  infixr 2 ||
  infixr 3 &&

  class BoolLike b where
    (&&) :: b -> b -> b
    (||) :: b -> b -> b
    not :: b -> b

  foreign import boolAnd "function boolAnd(b1) {\
                         \  return function(b2) {\
                         \    return b1 && b2;\
                         \  };\
                         \}"  :: Boolean -> Boolean -> Boolean

  foreign import boolOr "function boolOr(b1) {\
                        \  return function(b2) {\
                        \    return b1 || b2;\
                        \  };\
                        \}" :: Boolean -> Boolean -> Boolean

  foreign import boolNot "function boolNot(b) {\
                         \  return !b;\
                         \}" :: Boolean -> Boolean

  instance boolLikeBoolean :: BoolLike Boolean where
    (&&) = boolAnd
    (||) = boolOr
    not = boolNot

  infixr 5 <>

  class Semigroup a where
    (<>) :: a -> a -> a

  foreign import concatString
    "function concatString(s1) {\
    \  return function(s2) {\
    \    return s1 + s2;\
    \  };\
    \}" :: String -> String -> String

  instance semigroupUnit :: Semigroup Unit where
    (<>) (Unit {}) (Unit {}) = Unit {}

  instance semigroupString :: Semigroup String where
    (<>) = concatString

  infixr 5 ++

  (++) :: forall s. (Semigroup s) => s -> s -> s
  (++) = (<>)

module Data.Function where

  on :: forall a b c. (b -> b -> c) -> (a -> b) -> a -> a -> c
  on f g x y = g x `f` g y

module Data.Eq where

  data Ref a = Ref a

  liftRef :: forall a b. (a -> a -> b) -> Ref a -> Ref a -> b
  liftRef f (Ref x) (Ref y) = f x y

  instance eqRef :: Eq (Ref a) where
    (==) = liftRef refEq
    (/=) = liftRef refIneq

module Prelude.Unsafe where

  foreign import unsafeIndex
    "function unsafeIndex(xs) {\
    \  return function(n) {\
    \    return xs[n];\
    \  };\
    \}" :: forall a. [a] -> Number -> a

module Control.Monad.Eff where

  foreign import data Eff :: # ! -> * -> *

  foreign import returnE "function returnE(a) {\
                         \  return function() {\
                         \    return a;\
                         \  };\
                         \}" :: forall e a. a -> Eff e a

  foreign import bindE "function bindE(a) {\
                       \  return function(f) {\
                       \    return function() {\
                       \      return f(a())();\
                       \    };\
                       \  };\
                       \}" :: forall e a b. Eff e a -> (a -> Eff e b) -> Eff e b

  type Pure a = forall e. Eff e a

  foreign import runPure "function runPure(f) {\
                         \  return f();\
                         \}" :: forall a. Pure a -> a

  instance functorEff :: Functor (Eff e) where
    (<$>) = liftA1

  instance applyEff :: Apply (Eff e) where
    (<*>) = ap

  instance applicativeEff :: Applicative (Eff e) where
    pure = returnE

  instance bindEff :: Bind (Eff e) where
    (>>=) = bindE

  instance monadEff :: Monad (Eff e)

  foreign import untilE "function untilE(f) {\
                        \  return function() {\
                        \    while (!f()) { }\
                        \    return {};\
                        \  };\
                        \}" :: forall e. Eff e Boolean -> Eff e {}

  foreign import whileE "function whileE(f) {\
                        \  return function(a) {\
                        \    return function() {\
                        \      while (f()) {\
                        \        a();\
                        \      }\
                        \      return {};\
                        \    };\
                        \  };\
                        \}" :: forall e a. Eff e Boolean -> Eff e a -> Eff e {}

  foreign import forE "function forE(lo) {\
                      \  return function(hi) {\
                      \    return function(f) {\
                      \      return function() {\
                      \        for (var i = lo; i < hi; i++) {\
                      \          f(i)();\
                      \        }\
                      \      };\
                      \    };\
                      \  };\
                      \}" :: forall e. Number -> Number -> (Number -> Eff e {}) -> Eff e {}

  foreign import foreachE "function foreachE(as) {\
                          \  return function(f) {\
                          \    for (var i = 0; i < as.length; i++) {\
                          \      f(as[i])();\
                          \    }\
                          \  };\
                          \}" :: forall e a. [a] -> (a -> Eff e {}) -> Eff e {}

module Control.Monad.Eff.Unsafe where

  import Control.Monad.Eff

  foreign import unsafeInterleaveEff
    "function unsafeInterleaveEff(f) {\
    \  return f;\
    \}" :: forall eff1 eff2 a. Eff eff1 a -> Eff eff2 a

module Debug.Trace where

  import Control.Monad.Eff

  foreign import data Trace :: !

  foreign import trace "function trace(s) {\
                       \  return function() {\
                       \    console.log(s);\
                       \    return {};\
                       \  };\
                       \}" :: forall r. String -> Eff (trace :: Trace | r) {}

  print :: forall a r. (Show a) => a -> Eff (trace :: Trace | r) {}
  print o = trace (show o)

module Control.Monad.ST where

  import Control.Monad.Eff

  foreign import data ST :: * -> !

  foreign import data STRef :: * -> * -> *

  foreign import data STArray :: * -> * -> *

  foreign import newSTRef "function newSTRef(val) {\
                          \  return function () {\
                          \    return { value: val };\
                          \  };\
                          \}" :: forall a h r. a -> Eff (st :: ST h | r) (STRef h a)

  foreign import readSTRef "function readSTRef(ref) {\
                           \  return function() {\
                           \    return ref.value;\
                           \  };\
                           \}" :: forall a h r. STRef h a -> Eff (st :: ST h | r) a

  foreign import modifySTRef "function modifySTRef(ref) {\
                             \  return function(f) {\
                             \    return function() {\
                             \      return ref.value = f(ref.value);\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STRef h a -> (a -> a) -> Eff (st :: ST h | r) a

  foreign import writeSTRef "function writeSTRef(ref) {\
                            \  return function(a) {\
                            \    return function() {\
                            \      return ref.value = a;\
                            \    };\
                            \  };\
                            \}" :: forall a h r. STRef h a -> a -> Eff (st :: ST h | r) a

  foreign import newSTArray "function newSTArray(len) {\
                            \  return function(a) {\
                            \    return function() {\
                            \      var arr = [];\
                            \      for (var i = 0; i < len; i++) {\
                            \        arr[i] = a;\
                            \      };\
                            \      return arr;\
                            \    };\
                            \  };\
                            \}" :: forall a h r. Number -> a -> Eff (st :: ST h | r) (STArray h a)

  foreign import peekSTArray "function peekSTArray(arr) {\
                             \  return function(i) {\
                             \    return function() {\
                             \      return arr[i];\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STArray h a -> Eff (st :: ST h | r) a

  foreign import pokeSTArray "function pokeSTArray(arr) {\
                             \  return function(i) {\
                             \    return function(a) {\
                             \      return function() {\
                             \        return arr[i] = a;\
                             \      };\
                             \    };\
                             \  };\
                             \}" :: forall a h r. STArray h a -> Number -> a -> Eff (st :: ST h | r) a

  foreign import runST "function runST(f) {\
                       \  return f;\
                       \}" :: forall a r. (forall h. Eff (st :: ST h | r) a) -> Eff r a

  foreign import runSTArray "function runSTArray(f) {\
                            \  return f;\
                            \}" :: forall a r. (forall h. Eff (st :: ST h | r) (STArray h a)) -> Eff r [a]


rename connect as connectSpec

rename connect as connectSpec

module React.Redox
  ( ConnectState
  , withStore
  , connect
  , connectSpec
  , withDispatch
  , dispatch
  , RedoxContext
  , DispatchFn
  , unsafeShallowEqual
  , unsafeStrictEqual
  ) where

import Prelude

import Control.Monad.Aff (Canceler)
import Control.Monad.Eff (Eff, kind Effect)
import Control.Monad.Eff.Uncurried (EffFn1, EffFn2, runEffFn1, runEffFn2)
import Control.Monad.Eff.Unsafe (unsafeCoerceEff)
import Control.Monad.Free (Free)
import Data.Function.Uncurried (Fn2, Fn3, mkFn2, runFn2, runFn3)
import Data.Lens (Getter', view)
import Data.Maybe (Maybe(Just, Nothing))
import Data.Newtype (class Newtype, over)
import React (ReactClass, ReactElement, ReactSpec, ReactThis, createClassStateless', createElement, getProps, readState, writeState)
import React as R
import ReactHocs (CONTEXT, withContext, accessContext, readContext, getDisplayName)
import Redox as Redox
import Redox.Store (ReadRedox, RedoxStore, Store, SubscribeRedox, SubscriptionId)
import Type.Proxy (Proxy(..))
import Unsafe.Coerce (unsafeCoerce)

type DispatchFn state dsl reff eff = Free dsl (state -> state) -> Eff (redox :: RedoxStore reff | eff) (Canceler (redox :: RedoxStore reff | eff))

-- | Shallowly compare two objects.  If the first argument is true it skips
-- | comparing the `key` property which should not be accessed on a property
-- | object.
foreign import unsafeShallowEqual :: forall a. Fn3 Boolean a a Boolean

-- | Compare two objects using strict equality `===`
foreign import unsafeStrictEqual :: forall a. Fn2 a a Boolean

foreign import writeIsMountedImpl
  :: forall props state e
   . EffFn2 e (ReactThis props state) Boolean Unit

writeIsMounted :: forall props state e. ReactThis props state -> Boolean -> Eff e Unit
writeIsMounted this isMounted = runEffFn2 writeIsMountedImpl this isMounted

foreign import readIsMountedImpl
  :: forall props state e
   . EffFn1 e (ReactThis props state) Boolean

readIsMounted :: forall props state e. ReactThis props state -> Eff e Boolean
readIsMounted this = runEffFn1 readIsMountedImpl this

foreign import forceUpdateImpl :: forall eff props state.
  EffFn1 eff (ReactThis props state) Unit

-- | Force render of a react component.
forceUpdate :: forall eff props state.
  ReactThis props state -> Eff eff Unit
forceUpdate this = runEffFn1 forceUpdateImpl this

createClassStatelessWithContext
  :: forall props ctx
   . (props -> Array ReactElement -> ctx -> ReactElement)
  -> ReactClass props
createClassStatelessWithContext fn = unsafeCoerce f
  where
    -- using createClassStateless' ensures that children are coerced to `Array ReactElement`
    cls :: ctx -> ReactClass props
    cls ctx = createClassStateless' \props children -> fn props children ctx

    f :: Fn2 props { ctx :: ctx } ReactElement
    f = mkFn2 (\props { ctx } -> createElement (cls ctx) props (unsafeCoerce props).children)

newtype RedoxContext state dsl reff eff = RedoxContext
  { store :: Store state
  , dispatch :: DispatchFn state dsl reff eff
  }

-- | You need to wrap your most top-level component with `withStore`.  It makes
-- | the store and the bound dispatch function available through React context.
-- | Then you can connect a component with `connect` (or `connect'`) and get
-- | access to the store and the dispatch function.
withStore
  :: forall state props dsl reff eff
  -- redox store
   . Store state
  -- bound redox dispatch function
  -> (Store state -> DispatchFn state dsl reff eff)
  -> ReactClass props
  -> Eff eff (ReactClass props)
withStore store dispatch_ cls =
  pure $ withContext cls { redox: RedoxContext { store, dispatch: dispatch_ store } }

newtype ConnectState state = ConnectState { state :: state, sid :: Maybe SubscriptionId }

derive instance newtypeConnectState :: Newtype (ConnectState state) _

_connect
  :: forall state state' dsl props props' reff eff
   . (ReactThis props' (ConnectState state')
      -> Eff
        (context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff)
        (RedoxContext state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff)
     )
  -> Getter' state state'
  -> ((DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff) -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state')
      ( context :: CONTEXT
      , redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff)
      | eff
      )
_connect ctxEff _lns _iso cls = (R.spec' getInitialState renderFn)
    { displayName = getDisplayName cls <> "Connect"
    , componentDidMount = componentDidMount
    , componentWillUnmount = componentWillUnmount
    , shouldComponentUpdate = shouldComponentUpdate
    }
  where

    -- Connect the child component to the context, this is required for the
    -- `dispatch` function.
    cls_ :: ReactClass props
    cls_ = accessContext cls

    update this state = do
      st <- readState this
      isMounted <- readIsMounted this
      when isMounted do
        void $ writeState this $ over ConnectState (_ { state = view _lns state }) st

    getInitialState this = do
      -- unsafeCoerceEff is used to add react effects to ctxEff
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      state <- Redox.getState ctx.store
      pure (ConnectState { state: view _lns state, sid: Nothing })

    -- | Subscription to redox store happens in `componentDidMount`, rather than
    -- | on `componentWillMount`.  This is because `componentWillUnmount` and
    -- | `componentDidMount` do not fire in SSR. Otherwise we'd have a memory
    -- | leak.
    componentDidMount this = do
      writeIsMounted this true
      RedoxContext { store } <- unsafeCoerceEff $ ctxEff this
      st@ConnectState { state } <- readState this
      sid <- Redox.subscribe store $ update this
      _ <- writeState this (over ConnectState (_ { sid = Just sid }) st)
      state' <- view _lns <$> Redox.getState store
      when
        (runFn2 unsafeStrictEqual state state')
        (forceUpdate this)

    componentWillUnmount this = do
      writeIsMounted this false
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      ConnectState { sid: msid } <- R.readState this
      case msid of
        Nothing -> pure unit
        Just sid -> Redox.unsubscribe ctx.store sid

    shouldComponentUpdate this nPr (ConnectState nSt) = do
      pr <- getProps this
      ConnectState st <- readState this
      -- Take care only of `st.state` changes, `st.sid` is not used for
      -- rendering.
      let stateChanged = not $ runFn2 unsafeStrictEqual st.state nSt.state
          propsChanged = not $ runFn3 unsafeShallowEqual true pr nPr
      pure $ stateChanged || propsChanged

    renderFn this = do
      props' <- R.getProps this
      children <- R.getChildren this
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      ConnectState { state } <- R.readState this
      pure $ R.createElement cls_ (_iso ctx.dispatch state props') children

-- | You must wrap the resulting component with `ReactHocs.accessContext` from
-- | `purescript-react-hocs`.  Checkout `connect` bellow.  This function makes
-- | the redox store and dispatch function available through context.
-- | The first argument is a `Lens` that identifies the part of redox store's state
-- | that you want to subscribe for.  The view on this lens will be
-- | checked for changes, so if you want to optimise your code, return as 'tight'
-- | lens as possible.
-- |
-- | The second argument let you combine state and additional properties
-- | `props'` to get props of the class that you are connecting to the store.
-- | You can read the context with:
-- | ```purescript
-- | ReactHocs.readContext this >>= pure <<< _.redox :: Eff eff (RedoxContext state (Free dsl (state -> state))  eff)
-- | ```
connectSpec
  :: forall state state' dsl props props' reff eff
   . Proxy state
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state') ( context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff )
connectSpec _ _lns _iso cls = _connect ctxEff _lns _iso cls
  where
    proxy :: Proxy ({ redox :: RedoxContext state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff })
    proxy = Proxy

    ctxEff this = _.redox <$> readContext proxy this

-- | Like `connect'` but for `ReactClass`-es.
connect
  :: forall state state' dsl props props' reff eff'
   . Proxy state
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff' -> state' -> props' -> props)
  -> ReactClass props
  -> ReactClass props'
connect p _lns _iso cls = accessContext $ R.createClass $ connectSpec p _lns _iso cls

-- | If you just want to wrap your actions with a dispatch function use this
-- | function.  Unlike `connectSpec` (and `connect`) it does not wrap your
-- | component inside another component.
withDispatch
  :: forall state props props' dsl reff eff'
   . (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff' -> props' -> props)
  -> ReactClass props
  -> ReactClass props'
withDispatch fn cls = accessContext $ createClassStatelessWithContext
  \props' children { redox: RedoxContext { dispatch: disp }} -> createElement cls (fn disp props') children

-- | Light weight version of `connect`.  It does not require wrapping a parent
-- | with `withStore` since it is not using react context to access the store.
-- | You just need to provide the store with your first argument.
-- |
-- | Note: it is not safe to do server side rendering and keep the store as
-- | a global reference.  However, you can safely use this method if you are
-- | passing the store explicitly through props.
connectStore
  :: forall state state' dsl props props' reff eff
   . Store state
  -> DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state') ( context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff )
connectStore store dispatch_ _lns _iso cls = _connect (const $ pure (RedoxContext {store, dispatch: dispatch_})) _lns _iso cls

-- | If you wrapped your component with `connect` or `connectSpec` you can use
-- | this `dispatch` function to run your actions.
dispatch
  :: forall dsl rProps rState state reff eff
   . ReactThis rProps rState
  -> Free dsl (state -> state)
  -> Eff (context :: CONTEXT, redox :: RedoxStore reff | eff) (Canceler (context :: CONTEXT, redox :: RedoxStore reff | eff))
dispatch this dsl =
  let proxy :: Proxy ({ redox :: RedoxContext state dsl reff (context :: CONTEXT | eff) })
      proxy = Proxy
  in do
    { redox: RedoxContext { dispatch: disp } } <- readContext proxy this
    disp dsl

module React.Redox
  ( ConnectState
  , withStore
  , connect'
  , connect
  , withDispatch
  , dispatch
  , RedoxContext
  , DispatchFn
  , unsafeShallowEqual
  , unsafeStrictEqual
  ) where

import Prelude

import Control.Monad.Aff (Canceler)
import Control.Monad.Eff (Eff, kind Effect)
import Control.Monad.Eff.Uncurried (EffFn1, EffFn2, runEffFn1, runEffFn2)
import Control.Monad.Eff.Unsafe (unsafeCoerceEff)
import Control.Monad.Free (Free)
import Data.Function.Uncurried (Fn2, Fn3, mkFn2, runFn2, runFn3)
import Data.Lens (Getter', view)
import Data.Maybe (Maybe(Just, Nothing))
import Data.Newtype (class Newtype, over)
import React (ReactClass, ReactElement, ReactSpec, ReactThis, createClassStateless', createElement, getProps, readState, writeState)
import React as R
import ReactHocs (CONTEXT, withContext, accessContext, readContext, getDisplayName)
import Redox as Redox
import Redox.Store (ReadRedox, RedoxStore, Store, SubscribeRedox, SubscriptionId)
import Type.Proxy (Proxy(..))
import Unsafe.Coerce (unsafeCoerce)

type DispatchFn state dsl reff eff = Free dsl (state -> state) -> Eff (redox :: RedoxStore reff | eff) (Canceler (redox :: RedoxStore reff | eff))

-- | Shallowly compare two objects.  If the first argument is true it skips
-- | comparing the `key` property which should not be accessed on a property
-- | object.
foreign import unsafeShallowEqual :: forall a. Fn3 Boolean a a Boolean

-- | Compare two objects using strict equality `===`
foreign import unsafeStrictEqual :: forall a. Fn2 a a Boolean

foreign import writeIsMountedImpl
  :: forall props state e
   . EffFn2 e (ReactThis props state) Boolean Unit

writeIsMounted :: forall props state e. ReactThis props state -> Boolean -> Eff e Unit
writeIsMounted this isMounted = runEffFn2 writeIsMountedImpl this isMounted

foreign import readIsMountedImpl
  :: forall props state e
   . EffFn1 e (ReactThis props state) Boolean

readIsMounted :: forall props state e. ReactThis props state -> Eff e Boolean
readIsMounted this = runEffFn1 readIsMountedImpl this

foreign import forceUpdateImpl :: forall eff props state.
  EffFn1 eff (ReactThis props state) Unit

-- | Force render of a react component.
forceUpdate :: forall eff props state.
  ReactThis props state -> Eff eff Unit
forceUpdate this = runEffFn1 forceUpdateImpl this

createClassStatelessWithContext
  :: forall props ctx
   . (props -> Array ReactElement -> ctx -> ReactElement)
  -> ReactClass props
createClassStatelessWithContext fn = unsafeCoerce f
  where
    -- using createClassStateless' ensures that children are coerced to `Array ReactElement`
    cls :: ctx -> ReactClass props
    cls ctx = createClassStateless' \props children -> fn props children ctx

    f :: Fn2 props { ctx :: ctx } ReactElement
    f = mkFn2 (\props { ctx } -> createElement (cls ctx) props (unsafeCoerce props).children)

newtype RedoxContext state dsl reff eff = RedoxContext
  { store :: Store state
  , dispatch :: DispatchFn state dsl reff eff
  }

-- | You need to wrap your most top-level component with `withStore`.  It makes
-- | the store and the bound dispatch function available through React context.
-- | Then you can connect a component with `connect` (or `connect'`) and get
-- | access to the store and the dispatch function.
withStore
  :: forall state props dsl reff eff
  -- redox store
   . Store state
  -- bound redox dispatch function
  -> (Store state -> DispatchFn state dsl reff eff)
  -> ReactClass props
  -> Eff eff (ReactClass props)
withStore store dispatch_ cls =
  pure $ withContext cls { redox: RedoxContext { store, dispatch: dispatch_ store } }

newtype ConnectState state = ConnectState { state :: state, sid :: Maybe SubscriptionId }

derive instance newtypeConnectState :: Newtype (ConnectState state) _

_connect
  :: forall state state' dsl props props' reff eff
   . (ReactThis props' (ConnectState state')
      -> Eff
        (context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff)
        (RedoxContext state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff)
     )
  -> Getter' state state'
  -> ((DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff) -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state')
      ( context :: CONTEXT
      , redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff)
      | eff
      )
_connect ctxEff _lns _iso cls = (R.spec' getInitialState renderFn)
    { displayName = getDisplayName cls <> "Connect"
    , componentDidMount = componentDidMount
    , componentWillUnmount = componentWillUnmount
    , shouldComponentUpdate = shouldComponentUpdate
    }
  where

    -- Connect the child component to the context, this is required for the
    -- `dispatch` function.
    cls_ :: ReactClass props
    cls_ = accessContext cls

    update this state = do
      st <- readState this
      isMounted <- readIsMounted this
      when isMounted do
        void $ writeState this $ over ConnectState (_ { state = view _lns state }) st

    getInitialState this = do
      -- unsafeCoerceEff is used to add react effects to ctxEff
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      state <- Redox.getState ctx.store
      pure (ConnectState { state: view _lns state, sid: Nothing })

    -- | Subscription to redox store happens in `componentDidMount`, rather than
    -- | on `componentWillMount`.  This is because `componentWillUnmount` and
    -- | `componentDidMount` do not fire in SSR. Otherwise we'd have a memory
    -- | leak.
    componentDidMount this = do
      writeIsMounted this true
      RedoxContext { store } <- unsafeCoerceEff $ ctxEff this
      st@ConnectState { state } <- readState this
      sid <- Redox.subscribe store $ update this
      _ <- writeState this (over ConnectState (_ { sid = Just sid }) st)
      state' <- view _lns <$> Redox.getState store
      when
        (runFn2 unsafeStrictEqual state state')
        (forceUpdate this)

    componentWillUnmount this = do
      writeIsMounted this false
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      ConnectState { sid: msid } <- R.readState this
      case msid of
        Nothing -> pure unit
        Just sid -> Redox.unsubscribe ctx.store sid

    shouldComponentUpdate this nPr (ConnectState nSt) = do
      pr <- getProps this
      ConnectState st <- readState this
      -- Take care only of `st.state` changes, `st.sid` is not used for
      -- rendering.
      let stateChanged = not $ runFn2 unsafeStrictEqual st.state nSt.state
          propsChanged = not $ runFn3 unsafeShallowEqual true pr nPr
      pure $ stateChanged || propsChanged

    renderFn this = do
      props' <- R.getProps this
      children <- R.getChildren this
      RedoxContext ctx <- unsafeCoerceEff $ ctxEff this
      ConnectState { state } <- R.readState this
      pure $ R.createElement cls_ (_iso ctx.dispatch state props') children

-- | You must wrap the resulting component with `ReactHocs.accessContext` from
-- | `purescript-react-hocs`.  Checkout `connect` bellow.  This function makes
-- | the redox store and dispatch function available through context.
-- | The first argument is a `Lens` that identifies the part of redox store's state
-- | that you want to subscribe for.  The view on this lens will be
-- | checked for changes, so if you want to optimise your code, return as 'tight'
-- | lens as possible.
-- |
-- | The second argument let you combine state and additional properties
-- | `props'` to get props of the class that you are connecting to the store.
-- | You can read the context with:
-- | ```purescript
-- | ReactHocs.readContext this >>= pure <<< _.redox :: Eff eff (RedoxContext state (Free dsl (state -> state))  eff)
-- | ```
connect'
  :: forall state state' dsl props props' reff eff
   . Proxy state
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state') ( context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff )
connect' _ _lns _iso cls = _connect ctxEff _lns _iso cls
  where
    proxy :: Proxy ({ redox :: RedoxContext state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff })
    proxy = Proxy

    ctxEff this = _.redox <$> readContext proxy this

-- | Like `connect'` but for `ReactClass`-es.
connect
  :: forall state state' dsl props props' reff eff'
   . Proxy state
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff' -> state' -> props' -> props)
  -> ReactClass props
  -> ReactClass props'
connect p _lns _iso cls = accessContext $ R.createClass $ connect' p _lns _iso cls

-- | If you just want to wrap your actions with a dispatch function use this
-- | function.  Unlike `connect'` (and `connect`) it does not wrap your
-- | component inside another component.
withDispatch
  :: forall state props props' dsl reff eff'
   . (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff' -> props' -> props)
  -> ReactClass props
  -> ReactClass props'
withDispatch fn cls = accessContext $ createClassStatelessWithContext
  \props' children { redox: RedoxContext { dispatch: disp }} -> createElement cls (fn disp props') children

-- | Light weight version of `connect`.  It does not require wrapping a parent
-- | with `withStore` since it is not using react context to access the store.
-- | You just need to provide the store with your first argument.
-- |
-- | Note: it is not safe to do server side rendering and keep the store as
-- | a global reference.  However, you can safely use this method if you are
-- | passing the store explicitly through props.
connectStore
  :: forall state state' dsl props props' reff eff
   . Store state
  -> DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff
  -> Getter' state state'
  -> (DispatchFn state dsl (read :: ReadRedox, subscribe :: SubscribeRedox | reff) eff -> state' -> props' -> props)
  -> ReactClass props
  -> ReactSpec props' (ConnectState state') ( context :: CONTEXT, redox :: RedoxStore (read :: ReadRedox, subscribe :: SubscribeRedox | reff) | eff )
connectStore store dispatch_ _lns _iso cls = _connect (const $ pure (RedoxContext {store, dispatch: dispatch_})) _lns _iso cls

-- | If you wrapped your component with `connect` or `connect'` you can use
-- | this `dispatch` function to run your actions.
dispatch
  :: forall dsl rProps rState state reff eff
   . ReactThis rProps rState
  -> Free dsl (state -> state)
  -> Eff (context :: CONTEXT, redox :: RedoxStore reff | eff) (Canceler (context :: CONTEXT, redox :: RedoxStore reff | eff))
dispatch this dsl =
  let proxy :: Proxy ({ redox :: RedoxContext state dsl reff (context :: CONTEXT | eff) })
      proxy = Proxy
  in do
    { redox: RedoxContext { dispatch: disp } } <- readContext proxy this
    disp dsl