#!/usr/bin/env runhaskell

{-# LANGUAGE DeriveDataTypeable #-}

module Main where
import System.Console.CmdArgs 
import qualified Data.ByteString as B
import qualified Data.ByteString.Char8 as BC
import Text.Regex.TDFA
import Encoding.Base2           (enc2, dec2)
import Encoding.Base8           (enc8, dec8)
import Encoding.Base10          (enc10, dec10)
import Encoding.Base16          (enc16, dec16)
import Encoding.Base32          (enc32, dec32)
import Encoding.Base45          (enc45, dec45)
import Encoding.Base58          (enc58, dec58)
import Encoding.Base62          (enc62, dec62)
import Encoding.Base64          (enc64, dec64, enc64url, dec64url)
import Encoding.Base85          (enc85, dec85)
import Encoding.Base91          (enc91, dec91)
import Encoding.Url             (encurl, decurl)
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 { 
             b91 :: Bool,
             b85 :: Bool,
             b64 :: Bool,
             b64url :: Bool,
             url :: Bool,
             b62 :: Bool,
             b58 :: Bool,
             b45 :: Bool,
             b32 :: Bool,
             b16 :: Bool,
             b10 :: Bool,
             b8  :: Bool,
             b2  :: Bool,
             qp  :: Bool,
             uu  :: Bool,
             xx  :: Bool,
             yenc :: Bool,
             rot :: Maybe Int,
             solve :: Bool
                   }
          | Encode { 
             b91 :: Bool,
             b85 :: Bool, 
             b64 :: Bool,
             b64url :: Bool,
             url :: Bool,
             b62 :: Bool,
             b58 :: Bool,
             b45 :: Bool,
             b32 :: Bool,
             b16 :: Bool,
             b10 :: Bool,
             b8  :: Bool,
             b2  :: Bool,
             qp  :: Bool,
             uu  :: Bool,
             xx  :: Bool,
             yenc :: Bool,
             rot :: Maybe Int
                   } 
            deriving(Show, Data, Typeable) 

base91Regex = "^[!-~]*$"
base85Regex = "^[0-9A-Za-z!#$%&()*+,-;<=>?@^_`{|}~]+$"
base64Regex = "^([A-Za-z0-9+/]{4})*([A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{2}==)?$"
base58Regex = "^[1-9A-HJ-NP-Za-km-z]+$" -- incorrect
base32Regex = "^(?:[A-Z2-7]{8})*(?:[A-Z2-7]{2}={6}|[A-Z2-7]{4}={4}|[A-Z2-7]{5}={3}|[A-Z2-7]{7}=)?$"
base16Regex = "^[0-9A-FXx]*$"
base10Regex = "^[0-9]*$"
base8Regex = "^[0-7]*$"
base2Regex = "^[01]*$"
urlRegex = "^[a-zA-Z0-9%]*$"

solveEnc :: BC.ByteString -> BC.ByteString
solveEnc input =
   let isBase91 = input =~ base91Regex :: Bool
       isBase85 = input =~ base85Regex :: Bool
       isBase64 = input =~ base64Regex :: Bool
       isBase58 = input =~ base58Regex :: Bool
       isBase32 = input =~ base32Regex :: Bool
       isBase16 = input =~ base16Regex :: Bool
       isBase10 = input =~ base10Regex :: Bool
       isBase8  = input =~ base8Regex  :: Bool
       isBase2  = input =~ base2Regex  :: Bool
       isURL = input =~ urlRegex :: Bool
       base91Result = if isBase91 then BC.pack "\nTrying base91:\n" `BC.append` dec91 input else BC.empty
       base85Result = if isBase85 then BC.pack "\nTrying base85:\n" `BC.append` dec85 input else BC.empty
       base64Result = if isBase64 then BC.pack "\nTrying base64:\n" `BC.append` dec64 input else BC.empty
       base58Result = if isBase58 then BC.pack "\nTrying base58:\n" `BC.append` dec58 input else BC.empty
       base32Result = if isBase64 then BC.pack "\nTrying base32:\n" `BC.append` dec32 input else BC.empty
       base16Result = if isBase16 then BC.pack "\nTrying base16:\n" `BC.append` dec16 input else BC.empty
       base10Result = if isBase10 then BC.pack "\nTrying base10:\n" `BC.append` dec10 input else BC.empty
       base2Result  = if isBase2  then BC.pack "\nTrying base2:\n"  `BC.append` dec2  input else BC.empty
       base8Result  = if isBase8  then BC.pack "\nTrying base8:\n"  `BC.append` dec8  input else BC.empty
       urlResult    = if isURL    then BC.pack "\nTrying URL decode:\n" `BC.append` decurl input else BC.empty
   in BC.concat [base91Result, base85Result, base64Result, base58Result, base32Result, base16Result, base10Result, base8Result, base2Result,  urlResult]


optionHandler :: Based ->  B.ByteString -> B.ByteString
optionHandler Decode{b91=True} = dec91
optionHandler Encode{b91=True} = enc91
optionHandler Decode{b85=True} = dec85
optionHandler Encode{b85=True} = enc85
optionHandler Decode{b64=True} = dec64
optionHandler Encode{b64=True} = enc64
optionHandler Decode{b64url=True} = dec64url
optionHandler Encode{b64url=True} = enc64url
optionHandler Decode{url=True} = decurl
optionHandler Encode{url=True} = encurl
optionHandler Decode{b62=True} = dec62
optionHandler Encode{b62=True} = enc62
optionHandler Decode{b58=True} = dec58
optionHandler Encode{b58=True} = enc58
optionHandler Decode{b45=True} = dec45
optionHandler Encode{b45=True} = enc45
optionHandler Decode{b32=True} = dec32
optionHandler Encode{b32=True} = enc32
optionHandler Decode{b16=True} = dec16
optionHandler Encode{b16=True} = enc16
optionHandler Decode{b10=True} = dec10
optionHandler Encode{b10=True} = enc10
optionHandler Decode{b8=True}  = dec8
optionHandler Encode{b8=True}  = enc8
optionHandler Decode{b2=True}  = dec2
optionHandler Encode{b2=True}  = enc2
optionHandler Decode{qp=True}  = decqp
optionHandler Encode{qp=True}  = encqp
optionHandler Encode{uu=True}  = encuu
optionHandler Decode{uu=True}  = decuu
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
decodeMode = Decode {
           b91 = def &= help "decode base91",
           b85 = def &= help "decode base85",
           b64 = def &= help "decode base64",
           b64url = def &= help "decode base64Url",
           url = def &= help "decode URL",
           b62 = def &= help "decode base62",
           b58 = def &= help "decode base58",
           b45 = def &= help "decode base45",
           b32 = def &= help "decode base32",
           b16 = def &= help "decode base16",
           b10 = def &= help "decode decimal",
           b8  = def &= help "decode octal",
           b2  = def &= help "decode base2",
           qp  = def &= help "decode quoted-printable",
           uu  = def &= help "decode UnixToUnix",
           xx  = def &= help "decode xx, without padding",
           yenc = def &= help "decode yEncode",
           rot = def &= help "rotate characters by n positions",
           solve = def &= help "solve encoding"
       }  &= help "Decode chosen base" &=auto

encodeMode :: Based
encodeMode = Encode {
           b91 = def &= help "encode base91",
           b85 = def &= help "encode base85",
           b64 = def &= help "encode base64",
           b64url = def &= help "encode base64Url",
           url = def &= help "encode URL",
           b62 = def &= help "encode base62",
           b58 = def &= help "encode base58",
           b45 = def &= help "encode base45",
           b32 = def &= help "encode base32",
           b16 = def &= help "encode base16",
           b10 = def &= help "encode decimal",
           b8  = def &= help "encode octal", 
           b2  = def &= help "encode base2",
           qp  = def &= help "encode quoted-printable",
           uu  = def &= help "encode UnixToUnix",
           xx  = def &= help "encode xx, without padding",
           yenc = def &= help "encode yEncode",
           rot = def &= help "rotate characters by n positions" 
      } &= help "Encode chosen base"

main :: IO()
main = do
   args <- cmdArgs(modes[decodeMode, encodeMode] &= help "Based, Binary to text encoding.\nTo see arguments of encode and decode modes use --help=all" &= program "based" &= summary "based v0.4") 
   input <- B.getContents
   B.putStr $ optionHandler args input