import Control.Lens
import Data.List
import Data.List.Split
import qualified Data.Map as M
import Linear.V2

type Sensor = (V2 Int, V2 Int)

type Cave = M.Map (V2 Int) Char

main :: IO ()
main = do
  input <- map (splitOneOf "=,:") . lines <$> readFile "input"
  let sensors = map parse input
--  print $ "Cave from to: " ++ show (caveMinMaxX sensors)
--  print $ part1 (caveMinMaxX sensors) sensors
--  print $ getBorder sensors
--  print $ last [(x,x) | x<-[0..10000]]
--  print $ last [(x,y) | x<-[0..10000], y<-[0..10000], x==y]
  print "hello world"


allCandidates :: [Sensor] -> [Int] -> [V2 Int]
allCandidates (s:ss) ds = undefined

getBorder :: [Sensor] -> [V2 Int]
getBorder (s:ss) = map (+ (fst s)) xs ++ getBorder ss
    where xs = [V2 x (d - x) | x<-[-d..0]++[1..d]]
          d = succ $ dist s

caveMinMaxX :: [Sensor] -> (Int, Int)
caveMinMaxX sensors = (minimum k, maximum l)
  where
    d = map dist sensors
    s = map (view _y . fst) sensors
    k = zipWith (-) s d
    l = zipWith (+) s d

part1 :: (Int, Int) -> [Sensor] -> Int
part1 (a, b) sensors = length $ filter (== '#') $ map (checkPoint sensors) xs
  where
    xs = [V2 x 2000000 | x <- [a .. b]] --y=10 for testinput

parse :: [String] -> Sensor
parse [_, a, _, b, _, c, _, d] = (V2 (read a) (read b), V2 (read c) (read d))

checkPoint :: [Sensor] -> V2 Int -> Char
checkPoint sensors point
  | point `elem` map fst sensors = 'S'
  | point `elem` map snd sensors = 'B'
  | otherwise = checkPoint' sensors point
  where
    checkPoint' (s:ss) p =
      if dist (fst s, p) <= dist s
        then '#'
        else checkPoint' ss p
    checkPoint' [] _ = ' '

dist :: Sensor -> Int
dist (a, b) = sum $ abs $ a - b