{-# LANGUAGE CPP, MagicHash #-}

-- |
-- Module      : Data.Text.Internal.Unsafe.Char
-- Copyright   : (c) 2008, 2009 Tom Harper,
--               (c) 2009, 2010 Bryan O'Sullivan,
--               (c) 2009 Duncan Coutts
--
-- License     : BSD-style
-- Maintainer  : bos@serpentine.com
-- Stability   : experimental
-- Portability : GHC
--
-- /Warning/: this is an internal module, and does not have a stable
-- API or name. Functions in this module may not check or enforce
-- preconditions expected by public modules. Use at your own risk!
--
-- Fast character manipulation functions.
module Data.Text.Internal.Unsafe.Char
    (
      ord
    , unsafeChr16
    , unsafeChr8
    , unsafeChr32
    , unsafeWrite
    ) where

import Control.Monad.ST (ST)
import Data.Text.Internal.Encoding.Utf8
import GHC.Exts (Char(..), Int(..), chr#, ord#, word2Int#)
import GHC.Word (Word8(..), Word16(..), Word32(..))
import qualified Data.Text.Array as A
import Data.Text.Internal.PrimCompat ( word8ToWord#, word16ToWord#, word32ToWord# )
#if defined(ASSERTS)
import GHC.Stack (HasCallStack)
#endif

ord :: Char -> Int
ord :: Char -> Int
ord (C# Char#
c#) = Int# -> Int
I# (Char# -> Int#
ord# Char#
c#)
{-# INLINE ord #-}

-- | @since 2.0
unsafeChr16 :: Word16 -> Char
unsafeChr16 :: Word16 -> Char
unsafeChr16 (W16# Word16#
w#) = Char# -> Char
C# (Int# -> Char#
chr# (Word# -> Int#
word2Int# (Word16# -> Word#
word16ToWord# Word16#
w#)))
{-# INLINE unsafeChr16 #-}

unsafeChr8 :: Word8 -> Char
unsafeChr8 :: Word8 -> Char
unsafeChr8 (W8# Word8#
w#) = Char# -> Char
C# (Int# -> Char#
chr# (Word# -> Int#
word2Int# (Word8# -> Word#
word8ToWord# Word8#
w#)))
{-# INLINE unsafeChr8 #-}

unsafeChr32 :: Word32 -> Char
unsafeChr32 :: Word32 -> Char
unsafeChr32 (W32# Word32#
w#) = Char# -> Char
C# (Int# -> Char#
chr# (Word# -> Int#
word2Int# (Word32# -> Word#
word32ToWord# Word32#
w#)))
{-# INLINE unsafeChr32 #-}

-- | Write a character into the array at the given offset.  Returns
-- the number of 'Word8's written.
unsafeWrite ::
#if defined(ASSERTS)
    HasCallStack =>
#endif
    A.MArray s -> Int -> Char -> ST s Int
unsafeWrite :: forall s. MArray s -> Int -> Char -> ST s Int
unsafeWrite MArray s
marr Int
i Char
c = case Char -> Int
utf8Length Char
c of
    Int
1 -> do
        let n0 :: Word8
n0 = Int -> Word8
intToWord8 (Char -> Int
ord Char
c)
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr Int
i Word8
n0
        Int -> ST s Int
forall a. a -> ST s a
forall (m :: * -> *) a. Monad m => a -> m a
return Int
1
    Int
2 -> do
        let (Word8
n0, Word8
n1) = Char -> (Word8, Word8)
ord2 Char
c
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr Int
i     Word8
n0
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1) Word8
n1
        Int -> ST s Int
forall a. a -> ST s a
forall (m :: * -> *) a. Monad m => a -> m a
return Int
2
    Int
3 -> do
        let (Word8
n0, Word8
n1, Word8
n2) = Char -> (Word8, Word8, Word8)
ord3 Char
c
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr Int
i     Word8
n0
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1) Word8
n1
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
2) Word8
n2
        Int -> ST s Int
forall a. a -> ST s a
forall (m :: * -> *) a. Monad m => a -> m a
return Int
3
    Int
_ -> do
        let (Word8
n0, Word8
n1, Word8
n2, Word8
n3) = Char -> (Word8, Word8, Word8, Word8)
ord4 Char
c
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr Int
i     Word8
n0
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1) Word8
n1
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
2) Word8
n2
        MArray s -> Int -> Word8 -> ST s ()
forall s. MArray s -> Int -> Word8 -> ST s ()
A.unsafeWrite MArray s
marr (Int
iInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
3) Word8
n3
        Int -> ST s Int
forall a. a -> ST s a
forall (m :: * -> *) a. Monad m => a -> m a
return Int
4
{-# INLINE unsafeWrite #-}

intToWord8 :: Int -> Word8
intToWord8 :: Int -> Word8
intToWord8 = Int -> Word8
forall a b. (Integral a, Num b) => a -> b
fromIntegral