Vector.hs

{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE StrictData #-}

module Octane.Type.Vector (Vector(..)) where

import qualified Control.DeepSeq as DeepSeq
import qualified Data.Aeson as Aeson
import qualified GHC.Generics as Generics


-- | Three values packed together. Although the fields are called @x@, @y@, and
-- @z@, that may not be what they actually represent.
--
-- This cannot be an instance of 'Data.Binary.Bits.BinaryBit' because it is not
-- always serialized the same way. Sometimes it is three values run together,
-- but other times it has a flag for the presence of each value.
data Vector a = Vector
    { x :: a
    , y :: a
    , z :: a
    } deriving (Eq, Generics.Generic, Show)

instance (DeepSeq.NFData a) => DeepSeq.NFData (Vector a) where

-- | Encoded as a JSON array with 3 elements.
--
-- Aeson.encode (Vector 1 2 3 :: Vector Int)
-- "[1,2,3]"
instance (Aeson.ToJSON a) => Aeson.ToJSON (Vector a) where
    toJSON vector = Aeson.toJSON
        [ x vector
        , y vector
        , z vector
        ]