import Data.List.Split
import Data.List.Unique
import Data.Char as Char
import Data.List as List
import Data.Either as Either
import Debug.Trace as Trace
import Data.Maybe

main = do
    mapIn <-  lines <$> getContents
    --let brain = Amplifier software 0 0 [] [0]
    --let robot = Robot mapIn [((5,1),64)] (5,1) 1
    --let resultRobots = (runRobot robot )
    --let reachablePoints = getNextKey resultRobots
    --let nextKey = head (sortBy sortLength reachablePoints) 
    --let newMap = openGate mapIn nextKey
    let result = getAllKeys mapIn (15,1) []
    --let aRobotLength = List.minimum( map (length . points) $ aRobots)
    --let aRobotWin = filter(\(Robot brain points position direction) -> length points == aRobotLength) aRobots 
    --let winRobots = filter(\(Robot br pts pos dir) -> elem 2 (map(\(p,c) -> c) pts))resultRobots
    --let winRobotsLength = map(\(Robot br pts pos dir) -> length (filter(\(p,c) -> c == 1)pts))winRobots
    --let winRobot = (map(\(Robot br pts pos dir) -> Robot br [] pos 1) winRobots) !! 0
    --let part2Robots = (runRobot winRobot)
    --let part2Length = map(\(Robot br pts pos dir) -> length (filter(\(p,c) -> c == 1)pts))part2Robots
    --putStrLn(show winRobotsLength)
    --putStrLn(show $ List.maximum( part2Length))
    mapM putStrLn(map show mapIn)
    putStrLn(show result)
    
    --putStrLn(printKey nextKey)
    --mapM putStrLn(map show resultRobots)

data Robot = Robot{ brain:: [[Char]]
                    ,points:: [((Int,Int),Int)]
                    ,position:: (Int,Int)
                    ,direction :: Int
                    } deriving Show

data Key = Key { id :: Int,
                 pos :: (Int,Int),
                 way :: Int
               } deriving (Show, Eq)

getAllKeys :: [[Char]] -> (Int,Int) -> [Key] -> [[Key]]
getAllKeys mapIn (a,b) keys = do
        let robot = Robot (Trace.traceShowId(mapIn)) [((a,b),64)] (a,b) 1
        let resultRobots = (runRobot robot )
        let reachablKeys = (Trace.traceShowId(getNextKey (resultRobots)))
        if length reachablKeys /= 0
           then do
               let nextKey = head (sortBy sortLength reachablKeys)
               let newMap = openGate mapIn (Trace.traceShowId(nextKey))
               let newKeys = nextKey:keys
               getAllKeys newMap (pos nextKey) newKeys
           else keys
        

sortLength :: Key -> Key -> Ordering
sortLength (Key _ _ way1) (Key _ _ way2) 
	| way1 == way2 = EQ
        | way1 < way2 = LT
        | way1 > way2 = GT

openGate :: [[Char]] -> Key -> [[Char]]
openGate mapIn (Key id (a,b) _) = result
        where result' = map( map(\c -> if c==(chr id) then '.' else c)) mapIn 
	      result = map( map(\c -> if c==(chr (id-32)) then '.' else c)) result'

printKey :: Key -> [Char]
printKey (Key id pos way) = (show id)++" :"++(show pos)++(show way)

getBrain :: Robot -> [[Char]]
getBrain (Robot brain points poisition direction)  = brain


getNextKey :: [Robot] -> [Key]
getNextKey robots = nub minPts
          where kPts = map(\(Robot brain points position direction) ->(Key (snd(last points)) (fst(last points)) (length points))) robots
                minPts = map(\(Key id pos way) ->(Key id pos (min id))) keyWPr 
                min x = List.minimum  $ map(\(Key id pos way) -> way) $ filter(\(Key id pos way) -> id == x) keyWPr
                keys = filter(\(Key id pos way) -> id /= 46 && id /= 64 && between 97 id 122) kPts
                keyWPr = keys 
                

runRobot :: Robot -> [Robot]
runRobot robot 
  | (length move) == 0 = [robot]
  | (length move) == 1 = do
          let newRobot = stepRobot robot $ move!!0
          runRobot newRobot 
  | otherwise = do
               let newRobots = map(\mv -> stepRobot robot mv) move
               foldl (++) [] $ map(\robot ->  runRobot robot) newRobots
  where move = getNextMove robot  

stepRobot :: Robot -> Int -> Robot 
stepRobot (Robot brain points position direction) newDirection = do
        let newPos = move position newDirection 
        let statusResponse = ord ((brain!! (snd newPos))!! (fst newPos)) 
        let newPoints = (points) ++ [(newPos,  statusResponse)]
        if statusResponse == 35 || between 65 statusResponse 90 || between 97 statusResponse 122
          then Robot brain newPoints position newDirection
          else Robot brain newPoints newPos newDirection

between :: Int -> Int -> Int -> Bool
between x y z 
  |x <= y = y <= z
  |otherwise = False

move :: (Int,Int) -> Int -> (Int,Int)
move (x,y) direction 
               | direction == 1 = (x,y-1)
               | direction == 2 = (x+1,y)
               | direction == 3 = (x,y+1)
               | direction == 4 = (x-1,y)

getNextMove :: Robot -> [Int]
getNextMove (Robot brain points position direction) 
            |length points > 0 && (snd $ last points) == 2 = [] 
            |otherwise = do
                    filterMoves (Robot brain points position direction) [1,2,3,4]
                                        
filterMoves :: Robot -> [Int] -> [Int] 
filterMoves robot moves = filter(\x -> checkVisit robot x && checkWall robot x) moves

checkVisit :: Robot -> Int -> Bool
checkVisit (Robot brain points position direction) mv = do
        let newPos = move position mv
        let visits = map(\(pos,c) -> pos) points
        notElem newPos visits

checkWall :: Robot -> Int -> Bool
checkWall (Robot brain points position direction) mv = do
        let newPos = (move position mv)
	let mvResult = ( ord ((brain!! (snd newPos))!! (fst newPos)))
        not (mvResult == 35 ) 
        
getList :: String -> [Int]
getList = map Prelude.read . splitOn ","