-- IRC art (spam)bot

{-
   Copyright 2023 "Laura Aléanor"

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
-}

import Data.Bits
import qualified Data.ByteString as S
import qualified Data.ByteString.Char8 as S.Char8
import qualified Data.ByteString.Internal as S.Internal
import Data.List
import Data.Word
import System.Directory
import System.Environment
import System.Exit
import System.IO
import Text.Printf

type BitMap = [Word8]
type MircString = String

type PpmBmp = [Word8]

type IrcChannel = String

data Image = Image {
  imgBmp :: BitMap,
  imgPitch :: Int,
  imgHeight :: Int
  }

ctrlC = [toEnum 03] :: String
ctrlO = [toEnum 15] :: String
ctrlV = [toEnum 22] :: String

-- https://www.mirc.com/colors.html
w24ToMirc :: BitMap -> MircString
w24ToMirc word
  -- White
  | (word!!0 > 210) && (word!!1 > 210) && (word!!2 > 210)
  = "0"
  -- Black
  | (word!!0 == 0) && (word!!1 == 0) && (word!!2 == 0)
  = "1"
  -- Light red
  | (word!!0 > 127) && (word!!1 == 0) && (word!!2 == 0)
  = "4"
  -- Light green
  | (word!!0 == 0) && (word!!1 > 147) && (word!!2 == 0)
  = "9"
  -- Light blue
  | (word!!0 == 0) && (word!!1 == 0) && (word!!2 > 127)
  = "12"
  -- Red (aka brown)
  | (word!!0 <= 127) && (word!!1 == 0) && (word!!2 == 0)
  = "5"
  -- Green
  | (word!!0 == 0) && (word!!1 <= 147) && (word!!2 == 0)
  = "3"
  -- Blue
  | (word!!0 == 0) && (word!!1 == 0) && (word!!2 <= 127)
  = "2"
  -- Yellow
  | (word!!0 > 252) && (word!!1 > 127) && (word!!2 == 0)
  = "8"
  -- Orange
  | (word!!0 <= 252) && (word!!1 <= 127) && (word!!2 == 0)
  = "7"
  -- Pink
  | (word!!0 > 156) && (word!!1 == 0) && (word!!2 > 156)
  = "13"
  -- Purple
  | (word!!0 <= 156) && (word!!1 == 0) && (word!!2 <= 156)
  = "6"
  -- Light cyan
  | (word!!0 == 0) && (word!!1 > 147) && (word!!2 > 147)
  = "11"
  -- Cyan
  | (word!!0 == 0) && (word!!1 <= 147) && (word!!2 <= 147)
  = "10"
  -- Light grey
  | (word!!0 > 127) && (word!!1 > 127) && (word!!2 > 127)
  = "15"
  -- Grey
  | otherwise = "14"

lineToMirc :: BitMap -> MircString
lineToMirc [] = []
lineToMirc line = ctrlC ++ w24ToMirc (take 3 line) ++ ctrlV ++ "  " ++ ctrlO
                  ++ lineToMirc (drop 3 line)

bmpToMirc :: Int -> Int -> BitMap -> MircString
bmpToMirc _ 0 _ = []
bmpToMirc pitch height bmp =lineToMirc (take pitch bmp) ++ "\n"
                             ++ bmpToMirc pitch (height-1) (drop pitch bmp)

w8Split :: Word8 -> [Word8] -> [[Word8]]
w8Split c = map S.unpack . S.split c . S.pack

w8ToString :: [Word8] -> String
w8ToString = S.Char8.unpack . S.pack

ppmToImage :: PpmBmp -> Image
ppmToImage ppm = Image
                 (intercalate [S.Internal.c2w '\n'] $ drop 3
                                (w8Split (S.Internal.c2w '\n') ppm))
                 ((read (w8ToString
                   ((w8Split (S.Internal.c2w ' ') ((w8Split
                                    (S.Internal.c2w '\n') ppm) !! 1)) !! 0)))*3)
                 (read ( w8ToString
                   ((w8Split (S.Internal.c2w ' ') ((w8Split
                                   (S.Internal.c2w '\n') ppm) !! 1)) !! 1)))

ircConnect :: String -> MircString
ircConnect credentials = printf "NICK miaowe\r\n\
             \USER nya 0 * :mew mew\r\n\
             \PRIVMSG NickServ :IDENTIFY %s\r\n" credentials

waitForMessage :: (String -> Bool) -> IO String
waitForMessage p = getLine >>= \l -> if p l
                                     then return l
                                     else
                                       (if (words l)!!0 == "PING"
                                       then
                                          putStr
                                          ("PONG " ++ ((words l)!!1) ++ "\r\n")
                                          >> hFlush stdout
                                       else return ())
                                       >> waitForMessage p

waitForCloak :: IO String
waitForCloak = waitForMessage (\l -> (words l)!!1 == "396")

waitForCommand :: IO String
waitForCommand = waitForMessage (\l -> if ((length (words l)) >= 4)
                                       then ((words l)!!3 == ":miaowe:")
                                       else False)

joinChannel :: String -> IO ()
joinChannel c = putStr (printf "JOIN %s\r\n" c)

sendToChannel :: IrcChannel -> MircString -> IO ()
sendToChannel c s = (putStr $ concat $ map (\l -> printf "PRIVMSG %s :%s\r\n" c l)
                    (lines s)) >> hFlush stdout

sendFile :: IrcChannel -> FilePath -> IO ()
sendFile channel path = S.readFile path
                        >>= sendToChannel channel .
                        (\img ->bmpToMirc
                                (imgPitch img)
                                (imgHeight img)
                                (imgBmp img)) .
                        ppmToImage .
                        S.unpack .
                        S.Char8.pack .
                        intercalate "\n" .
                        filter (\l->not (head l == '#')) .
                        lines .
                        S.Char8.unpack

trySendFile :: IrcChannel -> FilePath -> IO ()
trySendFile channel path = (doesFileExist (path)
                            >>= (\b ->
                                    if b
                                    then
                                      sendFile channel (path)
                                    else
                                      sendToChannel channel "No such file."
                                    >> hFlush stdout))

processCommand :: IrcChannel -> MircString -> IO ()
processCommand channel command | (words command)!!4 == "Quit" = exitSuccess
                               | otherwise = (if isInfixOf "/" ((words command)!!4)
                                              then
                                                sendToChannel channel
                                                "Only PWD please."
                                              else
                                                trySendFile channel
                                                ((words command)!!4))

mainLoop :: IrcChannel -> IO ()
mainLoop channel = waitForCommand
                   >>= \line ->
                         processCommand channel line
                         >> mainLoop channel
                        

main :: IO ()
main =
  openFile "conf" ReadMode
  >>= hGetLine
  >>= putStr . ircConnect
  >> hFlush stdout
  >> waitForCloak
  >> hFlush stdout
  >> getArgs
  >>= \args ->
        joinChannel (args!!0)
        >> hFlush stdout
        >> mainLoop (args!!0)