{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE OverloadedLabels #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE TypeFamilies #-}

module Octane.Type.Word16
  ( Word16(..)
  , fromWord16
  , toWord16
  ) where

import Data.Function ((&))

import qualified Data.Aeson as Aeson
import qualified Data.Default.Class as Default
import qualified Data.OverloadedRecords.TH as OverloadedRecords
import qualified Data.Word as Word
import qualified Text.Printf as Printf

-- | A 16-bit unsigned integer.
newtype Word16 = Word16
  { word16Unpack :: Word.Word16
  } deriving (Eq, Num, Ord)

$(OverloadedRecords.overloadedRecord Default.def ''Word16)

-- | Shown as @0x0102@.
instance Show Word16 where
  show word16 = Printf.printf "0x%04x" (#unpack word16)

-- | Encoded as a JSON number.
instance Aeson.ToJSON Word16 where
  toJSON word16 = word16 & #unpack & Aeson.toJSON

-- | Converts a 'Word16' into any 'Integral' value.
fromWord16
  :: (Integral a)
  => Word16 -> a
fromWord16 word16 = fromIntegral (#unpack word16)

-- | Converts any 'Integral' value into a 'Word16'.
toWord16
  :: (Integral a)
  => a -> Word16
toWord16 value = Word16 (fromIntegral value)