From 5f113a044d1a17a7313124802b58c91819bc54eb Mon Sep 17 00:00:00 2001
From: PHO <pho@cielonegro.org>
Date: Sun, 10 Jul 2011 17:49:01 +0900
Subject: [PATCH] some data types

---
 Codec/Audio/WavPack/Entropy.hs | 21 ++++++++++++
 Codec/Audio/WavPack/Unpack.hs  | 36 --------------------
 Codec/Audio/WavPack/Words.hs   | 62 ++++++++++++++++++++++++++++++++++
 wavpack.cabal                  |  2 ++
 4 files changed, 85 insertions(+), 36 deletions(-)
 create mode 100644 Codec/Audio/WavPack/Entropy.hs
 create mode 100644 Codec/Audio/WavPack/Words.hs

diff --git a/Codec/Audio/WavPack/Entropy.hs b/Codec/Audio/WavPack/Entropy.hs
new file mode 100644
index 0000000..444fc17
--- /dev/null
+++ b/Codec/Audio/WavPack/Entropy.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE
+    UnicodeSyntax
+  #-}
+-- | FIXME
+module Codec.Audio.WavPack.Entropy
+    ( EntropyData(..)
+    )
+    where
+import Data.Word
+
+-- | FIXME
+data EntropyData
+    = EntropyData {
+        -- | Median log2 values for a channel.
+        edMedian     ∷ !(Word32, Word32, Word32)
+        -- | FIXME
+      , edSlowLevel  ∷ !Word32
+        -- | FIXME
+      , edErrorLimit ∷ !Word32
+      }
+    deriving (Eq, Show)
diff --git a/Codec/Audio/WavPack/Unpack.hs b/Codec/Audio/WavPack/Unpack.hs
index f816657..264072c 100644
--- a/Codec/Audio/WavPack/Unpack.hs
+++ b/Codec/Audio/WavPack/Unpack.hs
@@ -1,40 +1,4 @@
-{-# LANGUAGE
-    BangPatterns
-  , UnboxedTuples
-  , UnicodeSyntax
-  #-}
 module Codec.Audio.WavPack.Unpack
     (
     )
     where
-import Codec.Audio.WavPack.Internal
-import Data.Bits
-import Data.Bitstream.Generic (Bitstream)
-import qualified Data.Bitstream.Generic as B
-import Data.Word
-import Prelude.Unicode
-
--- Read a single unsigned value from the specified bitstream with a
--- value from 0 to maxCode. If there are exactly a power of two number
--- of possible codes then this will read a fixed number of bits;
--- otherwise it reads the minimum number of bits and then determines
--- whether another bit is needed to define the code.
-readCode ∷ Bitstream bs ⇒ bs → Word32 → (# Word32, bs #)
-{-# INLINEABLE readCode #-}
-readCode bs 0       = (# 0, bs #)
-readCode bs 1       = (# b2n (B.head bs), B.tail bs #)
-readCode bs maxCode
-    = let !bitCount = countBits maxCode
-          !extras   = bit bitCount - maxCode - 1
-          !code     = B.toBits (B.take (bitCount - 1) bs)
-          (# code', bitCount' #)
-                    = if code ≥ extras then
-                          (# (code `shiftL` 1)
-                             - extras
-                             + b2n (bs B.!! bitCount)
-                           , bitCount #)
-                      else
-                          (# code, bitCount - 1 #)
-          !bs'      = B.drop bitCount' bs
-      in
-        (# code', bs' #)
diff --git a/Codec/Audio/WavPack/Words.hs b/Codec/Audio/WavPack/Words.hs
new file mode 100644
index 0000000..0923547
--- /dev/null
+++ b/Codec/Audio/WavPack/Words.hs
@@ -0,0 +1,62 @@
+{-# LANGUAGE
+    BangPatterns
+  , UnboxedTuples
+  , UnicodeSyntax
+  #-}
+-- | FIXME
+module Codec.Audio.WavPack.Words
+    ( WordsData(..)
+    )
+    where
+import Codec.Audio.WavPack.Entropy
+import Codec.Audio.WavPack.Internal
+import Data.Bits
+import Data.Bitstream.Generic (Bitstream)
+import qualified Data.Bitstream.Generic as B
+import Data.Word
+import Prelude.Unicode
+
+-- | FIXME
+data WordsData
+    = WordsData {
+        wdBitrateDelta ∷ !(Word32, Word32)
+      , wdBitrateAcc   ∷ !(Word32, Word32)
+      , wdPendingData  ∷ !Word32
+      , wdHoldingOne   ∷ !Word32
+      , wdZeroesAcc    ∷ !Word32
+      , wdHoldingZero  ∷ !Bool
+      , wdPendingCount ∷ !Int
+      , wdEntropyData  ∷ !(EntropyData, EntropyData)
+      }
+    deriving (Eq, Show)
+
+-- This is an optimized version of 'getWord' that is used for lossless
+-- only (error_limit ≡ 0). Also, rather than obtaining a single
+-- sample, it can be used to obtain an entire buffer of either mono or
+-- stereo samples.
+--getWordsLossless ∷ 
+
+-- Read a single unsigned value from the specified bitstream with a
+-- value from 0 to maxCode. If there are exactly a power of two number
+-- of possible codes then this will read a fixed number of bits;
+-- otherwise it reads the minimum number of bits and then determines
+-- whether another bit is needed to define the code.
+readCode ∷ Bitstream bs ⇒ bs → Word32 → (# Word32, bs #)
+{-# INLINEABLE readCode #-}
+readCode bs 0       = (# 0, bs #)
+readCode bs 1       = (# b2n (B.head bs), B.tail bs #)
+readCode bs maxCode
+    = let !bitCount = countBits maxCode
+          !extras   = bit bitCount - maxCode - 1
+          !code     = B.toBits (B.take (bitCount - 1) bs)
+          (# code', bitCount' #)
+                    = if code ≥ extras then
+                          (# (code `shiftL` 1)
+                             - extras
+                             + b2n (bs B.!! bitCount)
+                           , bitCount #)
+                      else
+                          (# code, bitCount - 1 #)
+          !bs'      = B.drop bitCount' bs
+      in
+        (# code', bs' #)
diff --git a/wavpack.cabal b/wavpack.cabal
index e635c8f..c4eb301 100644
--- a/wavpack.cabal
+++ b/wavpack.cabal
@@ -44,8 +44,10 @@ Library
         Codec.Audio.WavPack
         Codec.Audio.WavPack.Block
         Codec.Audio.WavPack.Decorrelation
+        Codec.Audio.WavPack.Entropy
         Codec.Audio.WavPack.Internal
         Codec.Audio.WavPack.Metadata
+        Codec.Audio.WavPack.Words
         Codec.Audio.WavPack.Unpack
 
     GHC-Options:
-- 
2.40.0