From 146293eeb4788b41803cfc551e6001dcaf8d1491 Mon Sep 17 00:00:00 2001
From: Stefan Friese <mail@stefan.works>
Date: Wed, 22 May 2024 21:58:40 +0200
Subject: [PATCH] added rotate functions for n rotations of the alphabet

---
 CHANGELOG.md           | 18 +++++++++++++++++-
 app/Main.hs            | 15 +++++++++++----
 based.cabal            |  1 +
 src/Encoding/Rotate.hs | 22 ++++++++++++++++++++++
 4 files changed, 51 insertions(+), 5 deletions(-)
 create mode 100644 src/Encoding/Rotate.hs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e673181..222de44 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,16 @@
 Revision history for based
 
+0.4.3.0 -- 2024-05-22
+
+    Added rotate function to encode and decode
+    Added solver function to decode, to automatically solve some of the encodings, ongoing
+    Added tests for some of the encode and decode functions, ongoing
+    Added unicode support for most of the encoding/decoding functions, ongoing
+    Modularized Encodings to a lib, instead having everything in a single flat file
+    Cleanup of cabal file
+
 0.4.2.0 -- 2023-07-25
+
     Changed Base64 decoding to Base64 lenient
     Cleanup
 
@@ -17,7 +27,13 @@ Revision history for based
 
 0.2.0.0 -- 2022-05-19
 
-    Added the following bases and encodings * Decimal to hex * Hex to decmial * Xxencoding * UuEncoding * YEncoding * Quoted-Printable
+    Added the following bases and encodings 
+    * Decimal to hex 
+    * Hex to decmial 
+    * Xxencoding 
+    * UuEncoding
+    * YEncoding
+    * Quoted-Printable
 
 0.1.0.0 -- 2022-05-17
 
diff --git a/app/Main.hs b/app/Main.hs
index 31baae2..791176d 100644
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -23,6 +23,7 @@ import Encoding.Xx              (encxx, decxx)
 import Encoding.QuotedPrintable (encqp, decqp)
 import Encoding.UnixToUnix      (encuu, decuu)
 import Encoding.Yenc            (ency, decy)
+import Encoding.Rotate          (rotate)
 
 
 data Based = Decode { 
@@ -42,6 +43,7 @@ data Based = Decode {
               uu  :: Bool,
               xx  :: Bool,
               yenc :: Bool,
+              rot :: Maybe Int,
               solve :: Bool
                     }
            | Encode { 
@@ -60,8 +62,9 @@ data Based = Decode {
               qp  :: Bool,
               uu  :: Bool,
               xx  :: Bool,
-              yenc :: Bool
-                     } 
+              yenc :: Bool,
+              rot :: Maybe Int
+                    } 
              deriving(Show, Data, Typeable) 
 
 -- helper functions
@@ -175,6 +178,8 @@ optionHandler Decode{xx=True}  = decxx
 optionHandler Encode{xx=True}  = encxx
 optionHandler Decode{yenc=True}   = decy
 optionHandler Encode{yenc=True}   = ency
+optionHandler Encode{rot=Just n} = rotate n
+optionHandler Decode{rot=Just n} = rotate n
 optionHandler Decode{solve=True} = solveEnc
 
 decodeMode :: Based
@@ -195,6 +200,7 @@ decodeMode = Decode {
             uu  = def &= help "decode uu",
             xx  = def &= help "decode xx",
             yenc = def &= help "decode yEncode",
+            rot = def &= help "rotate characters by n positions",
             solve = def &= help "solve encoding"
         }  &= help "Decode chosen base" &=auto
 
@@ -215,8 +221,9 @@ encodeMode = Encode {
             qp  = def &= help "encode quoted-printable",
             uu  = def &= help "encode uu",
             xx  = def &= help "encode xx",
-            yenc = def &= help "encode yEncode"
+            yenc = def &= help "encode yEncode",
+            rot = def &= help "rotate characters by n positions" 
        } &= help "Encode chosen base"
 
 main :: IO()
-main = cmdArgs (modes[decodeMode, encodeMode] &= help "Anybased, when Cyberchef simply doesn't cut it.\nTo see every parameter of every mode use --help=all" &= program "based" &= summary "based v0.4") >>= interact . optionHandler
+main = cmdArgs (modes[decodeMode, encodeMode] &= help "Based, when Cyberchef doesn't cut it.\nTo see every parameter of every mode use --help=all" &= program "based" &= summary "based v0.4") >>= interact . optionHandler
diff --git a/based.cabal b/based.cabal
index a1a6847..5a64051 100644
--- a/based.cabal
+++ b/based.cabal
@@ -23,6 +23,7 @@ library
     Encoding.UnixToUnix
     Encoding.Xx
     Encoding.Yenc
+    Encoding.Rotate
   other-modules:
     -- Data.Bytes.Text.Ascii
   build-depends:
diff --git a/src/Encoding/Rotate.hs b/src/Encoding/Rotate.hs
new file mode 100644
index 0000000..fde0e53
--- /dev/null
+++ b/src/Encoding/Rotate.hs
@@ -0,0 +1,22 @@
+module Encoding.Rotate
+  ( rotate ) where
+
+import Data.Maybe (fromMaybe)
+
+upperCase = ['A' .. 'Z']
+lowerCase = ['a' .. 'z']
+
+-- rotate :: Int * -> String
+rotate :: Int -> String -> String
+rotate n s = map (rotchar n) s
+  where
+    rotchar n c = 
+      case (lookup c $ transp n lowerCase) of
+        Just x -> x
+        Nothing -> fromMaybe c (lookup c $ transp n upperCase)
+
+transp :: Int -> [Char] -> [(Char, Char)]
+transp n x = zip x ((drop n x) ++ (take n x))
+
+
+