module PtrPoker.Write
where

import PtrPoker.Prelude
import qualified PtrPoker.IO.ByteString as ByteStringIO
import qualified PtrPoker.IO.Prim as PrimIO
import qualified PtrPoker.Poke as Poke
import qualified PtrPoker.Size as Size
import qualified PtrPoker.Ffi as Ffi
import qualified PtrPoker.ByteString as ByteString
import qualified Data.ByteString as ByteString
import qualified Data.ByteString.Internal as ByteString


{-# INLINABLE writeToByteString #-}
writeToByteString :: Write -> ByteString
writeToByteString Write{..} =
  ByteString.unsafeCreate writeSize (void . Poke.pokePtr writePoke)

{-|
Specification of how much bytes to allocate and how to populate them.

Useful for creating strict bytestrings and tasks like that.
-}
data Write =
  Write {
    writeSize :: Int,
    writePoke :: Poke.Poke
    }

instance Semigroup Write where
  {-# INLINE (<>) #-}
  Write lSize lPoke <> Write rSize rPoke =
    Write (lSize + rSize) (lPoke <> rPoke)

instance Monoid Write where
  {-# INLINE mempty #-}
  mempty =
    Write 0 mempty

instance IsString Write where
  {-# INLINE fromString #-}
  fromString =
    byteString . fromString

{-# INLINE word8 #-}
word8 :: Word8 -> Write
word8 a =
  Write 1 (Poke.word8 a)

{-# INLINE word64AsciiDec #-}
word64AsciiDec :: Word64 -> Write
word64AsciiDec a =
  Write size poke
  where
    size =
      Size.word64AsciiDec a
    poke =
      Poke.sizedReverse size (Ffi.revPokeUInt64 (fromIntegral a))

{-# INLINE wordAsciiDec #-}
wordAsciiDec :: Word -> Write
wordAsciiDec =
  word64AsciiDec . fromIntegral

{-# INLINE int64AsciiDec #-}
int64AsciiDec :: Int64 -> Write
int64AsciiDec a =
  Write size poke
  where
    size =
      Size.int64AsciiDec a
    poke =
      Poke.sizedReverse size (Ffi.revPokeInt64 (fromIntegral a))

{-# INLINE intAsciiDec #-}
intAsciiDec :: Int -> Write
intAsciiDec =
  int64AsciiDec . fromIntegral

{-|
Render double interpreting non-real values,
such as @NaN@, @Infinity@, @-Infinity@,
as is.
-}
{-# INLINE doubleAsciiDec #-}
doubleAsciiDec :: Double -> Write
doubleAsciiDec a =
  if a == 0
    then word8 48
    else if isNaN a
      then "NaN"
      else if isInfinite a
        then if a < 0
          then "-Infinity"
          else "Infinity"
        else if a < 0
          then word8 45 <> byteString (ByteString.double (negate a))
          else byteString (ByteString.double a)

{-|
Render double interpreting non real values,
such as @NaN@, @Infinity@, @-Infinity@,
as zero.
-}
{-# INLINE zeroNonRealDoubleAsciiDec #-}
zeroNonRealDoubleAsciiDec :: Double -> Write
zeroNonRealDoubleAsciiDec a =
  if a == 0 || isNaN a || isInfinite a
    then word8 48
    else if a < 0
      then word8 45 <> byteString (ByteString.double (negate a))
      else byteString (ByteString.double a)

{-# INLINE scientificAsciiDec #-}
scientificAsciiDec :: Scientific -> Write
scientificAsciiDec =
  byteString . ByteString.scientific

{-# INLINE byteString #-}
byteString :: ByteString -> Write
byteString a =
  Write (ByteString.length a) (inline Poke.byteString a)

{-|
Benchmark results in comparison to @Data.Text.Encoding.'Data.Text.Encoding.decodeUtf8'@.

> textUtf8/ptr-poker/latin/1               mean 57.06 ns  ( +- 3.283 ns  )
> textUtf8/ptr-poker/latin/10              mean 214.1 ns  ( +- 8.601 ns  )
> textUtf8/ptr-poker/latin/100             mean 1.536 μs  ( +- 75.03 ns  )
> textUtf8/ptr-poker/greek/1               mean 85.98 ns  ( +- 5.038 ns  )
> textUtf8/ptr-poker/greek/10              mean 482.1 ns  ( +- 12.38 ns  )
> textUtf8/ptr-poker/greek/100             mean 4.398 μs  ( +- 33.94 ns  )
> textUtf8/text/latin/1                    mean 60.28 ns  ( +- 3.517 ns  )
> textUtf8/text/latin/10                   mean 201.6 ns  ( +- 8.118 ns  )
> textUtf8/text/latin/100                  mean 1.323 μs  ( +- 51.25 ns  )
> textUtf8/text/greek/1                    mean 99.14 ns  ( +- 1.264 ns  )
> textUtf8/text/greek/10                   mean 483.4 ns  ( +- 5.844 ns  )
> textUtf8/text/greek/100                  mean 4.238 μs  ( +- 40.55 ns  )
-}
{-# INLINABLE textUtf8 #-}
textUtf8 :: Text -> Write
textUtf8 =
  byteString . ByteString.textUtf8