From 6ab4cbaa79520fc1565d1142a4128765739f023c Mon Sep 17 00:00:00 2001
From: Stefan Friese <mail@stefan.works>
Date: Sun, 9 Jun 2024 15:32:39 +0200
Subject: [PATCH] moved all encodings to bytestring in- and output

---
 src/Encoding/Base2.hs  | 19 +++++++++++++++++--
 src/Encoding/Base45.hs |  8 +++++---
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/Encoding/Base2.hs b/src/Encoding/Base2.hs
index e44e4d3..2365ee9 100644
--- a/src/Encoding/Base2.hs
+++ b/src/Encoding/Base2.hs
@@ -37,6 +37,8 @@ import Data.Char (ord, chr, digitToInt, intToDigit)
 import qualified Data.ByteString.Char8 as BC
 import Data.ByteString (ByteString)
 import qualified Data.ByteString as B
+import Data.Bits ((.&.), shiftR)
+import Data.List (unfoldr)
 
 binaryToChar :: ByteString -> Char
 binaryToChar binStr = chr $ binaryToInt (BC.unpack binStr)
@@ -47,10 +49,20 @@ binaryToInt binStr = foldl (\acc x -> acc * 2 + digitToInt x) 0 binStr
 dec2 :: ByteString -> ByteString
 dec2 input = BC.pack . map binaryToChar . BC.words $ input
 
+-- charToBinary :: Char -> ByteString
+-- charToBinary char = BC.pack $ replicate (7 - length binaryStr) '0' ++ binaryStr
+--   where
+--     binaryStr = intToBinary (ord char)
 charToBinary :: Char -> ByteString
-charToBinary char = BC.pack $ replicate (7 - length binaryStr) '0' ++ binaryStr
+charToBinary char = BC.pack $ replicate (8 - length binaryStr) '0' ++ binaryStr
   where
-    binaryStr = intToBinary (ord char)
+    codePoint = ord char
+    binaryStr = padToLength 8 (intToBinary' codePoint)
+
+padToLength :: Int -> String -> String
+padToLength len str
+  | length str >= len = take len str
+  | otherwise = replicate (len - length str) '0' ++ str
 
 intToBinary :: Int -> String
 intToBinary n = reverse $ decimalToBinary' n
@@ -58,5 +70,8 @@ intToBinary n = reverse $ decimalToBinary' n
     decimalToBinary' 0 = "0"
     decimalToBinary' m = let (q, r) = m `divMod` 2 in intToDigit r : decimalToBinary' q
 
+intToBinary' :: Int -> String
+intToBinary' n = reverse $ take 8 $ unfoldr (\x -> if x == 0 then Nothing else Just (intToDigit $ x .&. 1, x `shiftR` 1)) n
+
 enc2 :: ByteString -> ByteString
 enc2 input = BC.unwords . map charToBinary . BC.unpack $ input
diff --git a/src/Encoding/Base45.hs b/src/Encoding/Base45.hs
index 91d9e4b..71970db 100644
--- a/src/Encoding/Base45.hs
+++ b/src/Encoding/Base45.hs
@@ -142,7 +142,7 @@ encodeChunk [x1] = BC.pack $ map (BC.index base45Alphabet) [b, a]
 encodeChunk _ = error "Invalid chunk length"
 
 dec45 :: ByteString -> ByteString
-dec45 encoded = B.pack $ map fromIntegral decodedBytes
+dec45 encoded = B.pack decodedBytes
   where
     numericValues = map charToNumeric (BC.unpack encoded)
     groups = groupIntoThrees numericValues
@@ -162,8 +162,10 @@ toBase45 :: [Int] -> Int
 toBase45 [c, d, e] = c + d * 45 + e * (45 * 45)
 toBase45 _ = error "Invalid Base45 group"
 
-fromBase45 :: Int -> [Int]
-fromBase45 n = unfoldr (\x -> if x == 0 then Nothing else Just (x `mod` 256, x `div` 256)) n
+-- fromBase45 :: Int -> [Int]
+-- fromBase45 n = unfoldr (\x -> if x == 0 then Nothing else Just (x `mod` 256, x `div` 256)) n
+fromBase45 :: Int -> [Word8]
+fromBase45 n = reverse $ unfoldr (\x -> if x == 0 then Nothing else Just (fromIntegral $ x `mod` 256, x `div` 256)) n
 
 bytesToChars :: [Int] -> [Char]
 bytesToChars = map chr