From 6c5011aaa30bdf9eac3b85e2a548bb3b8dca7888 Mon Sep 17 00:00:00 2001
From: Henning Guenther <h.guenther@tu-bs.de>
Date: Sun, 20 Jan 2008 13:33:22 -0800
Subject: [PATCH] Added KOI8U encoding

darcs-hash:20080120213322-a4fee-752cc3f3ec4e7a01e5bbf93bad08a88ca3cb3a5b
---
 Data/Encoding.hs       |  2 ++
 Data/Encoding/KOI8R.hs |  3 +-
 Data/Encoding/KOI8U.hs | 64 ++++++++++++++++++++++++++++++++++++++++++
 encoding.cabal         |  1 +
 4 files changed, 69 insertions(+), 1 deletion(-)
 create mode 100644 Data/Encoding/KOI8U.hs

diff --git a/Data/Encoding.hs b/Data/Encoding.hs
index 1b7a189..0962372 100644
--- a/Data/Encoding.hs
+++ b/Data/Encoding.hs
@@ -44,6 +44,7 @@ import Data.Encoding.CP1256
 import Data.Encoding.CP1257
 import Data.Encoding.CP1258
 import Data.Encoding.KOI8R
+import Data.Encoding.KOI8U
 import Data.Encoding.GB18030
 
 -- | An untyped encoding. Used in 'System.IO.Encoding.getSystemEncoding'.
@@ -80,6 +81,7 @@ encodingFromStringMaybe "UTF-8"		= Just $ DynEncoding UTF8
 encodingFromStringMaybe "UTF-16"	= Just $ DynEncoding UTF16
 encodingFromStringMaybe "UTF-32"	= Just $ DynEncoding UTF32
 encodingFromStringMaybe "KOI8-R"	= Just $ DynEncoding KOI8R
+encodingFromStringMaybe "KOI8-U"	= Just $ DynEncoding KOI8U
 encodingFromStringMaybe "ISO-8859-1"	= Just $ DynEncoding ISO88591
 encodingFromStringMaybe "ISO-8859-2"	= Just $ DynEncoding ISO88592
 encodingFromStringMaybe "ISO-8859-3"	= Just $ DynEncoding ISO88593
diff --git a/Data/Encoding/KOI8R.hs b/Data/Encoding/KOI8R.hs
index 79c0b67..1a0ab39 100644
--- a/Data/Encoding/KOI8R.hs
+++ b/Data/Encoding/KOI8R.hs
@@ -41,7 +41,8 @@ koi8rList =
 	,'\x042e','\x0410','\x0411','\x0426','\x0414','\x0415','\x0424','\x0413'
 	,'\x0425','\x0418','\x0419','\x041a','\x041b','\x041c','\x041d','\x041e'
 	,'\x041f','\x042f','\x0420','\x0421','\x0422','\x0423','\x0416','\x0412'
-	,'\x042c','\x042b','\x0417','\x0428','\x042d','\x0429','\x0427','\x042a']
+	,'\x042c','\x042b','\x0417','\x0428','\x042d','\x0429','\x0427','\x042a'
+	]
 
 koi8rDecode :: Word8 -> Char
 koi8rDecode ch
diff --git a/Data/Encoding/KOI8U.hs b/Data/Encoding/KOI8U.hs
new file mode 100644
index 0000000..fb4970d
--- /dev/null
+++ b/Data/Encoding/KOI8U.hs
@@ -0,0 +1,64 @@
+{-# LANGUAGE DeriveDataTypeable #-}
+{- | This module implements KOI8-U encoding which covers the ukrainian alphabet.
+     See <http://en.wikipedia.org/wiki/KOI8-U> for more information.
+ -}
+module Data.Encoding.KOI8U
+	(KOI8U(..)) where
+
+import Control.Exception (throwDyn)
+import Data.Word
+import Data.Array.Unboxed
+import Data.Encoding.Base
+import Data.Char (chr,ord)
+import Data.Map (Map,fromList,lookup,member)
+import qualified Data.ByteString.Lazy as Lazy
+import Prelude hiding (lookup)
+import Data.Typeable
+
+data KOI8U = KOI8U deriving (Eq,Show,Typeable)
+
+koi8uArr :: UArray Word8 Char
+koi8uArr = listArray (128,255) koi8uList
+
+koi8uMap :: Map Char Word8
+koi8uMap = fromList (zip koi8uList [0..])
+
+koi8uList :: [Char]
+koi8uList =
+	['\x2500','\x2502','\x250c','\x2510','\x2514','\x2518','\x251c','\x2524'
+	,'\x252c','\x2534','\x253c','\x2580','\x2584','\x2588','\x258c','\x2590'
+	,'\x2591','\x2592','\x2593','\x2320','\x25a0','\x2219','\x221a','\x2248'
+	,'\x2264','\x2265','\x00a0','\x2321','\x00b0','\x00b2','\x00b7','\x00f7'
+	,'\x2550','\x2551','\x2552','\x0451','\x0454','\x2554','\x0456','\x0457'
+	,'\x2557','\x2558','\x2559','\x255a','\x255b','\x0491','\x255d','\x255e'
+	,'\x255f','\x2560','\x2561','\x0401','\x0403','\x2563','\x0406','\x0407'
+	,'\x2566','\x2567','\x2568','\x2569','\x256a','\x0490','\x256c','\x00a9'
+	,'\x044e','\x0430','\x0431','\x0446','\x0434','\x0435','\x0444','\x0433'
+	,'\x0445','\x0438','\x0439','\x043a','\x043b','\x043c','\x043d','\x043e'
+	,'\x043f','\x044f','\x0440','\x0441','\x0442','\x0443','\x0436','\x0432'
+	,'\x044c','\x044b','\x0437','\x0448','\x044d','\x0449','\x0447','\x044a'
+	,'\x042e','\x0410','\x0411','\x0426','\x0414','\x0415','\x0424','\x0413'
+	,'\x0425','\x0418','\x0419','\x041a','\x041b','\x041c','\x041d','\x041e'
+	,'\x041f','\x042f','\x0420','\x0421','\x0422','\x0423','\x0416','\x0412'
+	,'\x042c','\x042b','\x0417','\x0428','\x042d','\x0429','\x0427','\x042a'
+	]
+
+koi8uDecode :: Word8 -> Char
+koi8uDecode ch
+	| ch < 128  = chr $ fromIntegral ch
+	| otherwise = koi8uArr!ch
+
+koi8uEncode :: Char -> Word8
+koi8uEncode ch
+	| ch < '\128' = fromIntegral $ ord ch
+	| otherwise   = case lookup ch koi8uMap of
+		Just w  -> w
+		Nothing -> throwDyn (HasNoRepresentation ch)
+
+instance Encoding KOI8U where
+	encode _ = encodeSinglebyte koi8uEncode
+	encodeLazy _ = encodeSinglebyteLazy koi8uEncode
+	encodable _ c = (c < '\128') || (member c koi8uMap)
+	decode _ = decodeSinglebyte koi8uDecode
+	decodeLazy _ str = concatMap (decodeSinglebyte koi8uDecode) (Lazy.toChunks str)
+	decodable _ = const True
diff --git a/encoding.cabal b/encoding.cabal
index 736395b..6758311 100644
--- a/encoding.cabal
+++ b/encoding.cabal
@@ -83,6 +83,7 @@ Library
     Data.Encoding.CP1257
     Data.Encoding.CP1258
     Data.Encoding.KOI8R
+    Data.Encoding.KOI8U
     Data.Encoding.GB18030
     System.IO.Encoding
   Other-Modules: