Main.hs

{-
MIT License

Copyright (c) 2021 Andrew E Riachi

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
-}

module Main where

import Text.Read
import System.Random
import Data.Char
import Data.List
import System.Environment
import System.IO

main :: IO ()
main = do
         (hSetBuffering stdout NoBuffering)
         game

blankBoard :: Board
blankBoard = Board ((replicate 10 . replicate 10) BlankSquare)

addSquare :: (Int,Int) -> Square -> Board -> Board
addSquare (x,y) square (Board board) = Board ((take x board) ++ [row] ++ (drop (x+1) board))
  where row = (take y (board !! x)) ++ [square] ++ (drop (y+1) (board !! x))

generateBoard :: [(Int,Int)] -> [(Int,Int)] -> [Boat] -> Board
generateBoard [] [] [] = blankBoard
generateBoard [] [] ((Boat [] _t):boats) = generateBoard [] [] boats
generateBoard [] [] ((Boat (coord:coords) t):boats) = addSquare coord square (generateBoard [] [] ((Boat coords t):boats))
  where square = case t of 
                   Haskellship -> HaskellSquare
                   _           -> BoatSquare
generateBoard [] (miss:misses) boats = addSquare miss MissSquare (generateBoard [] misses boats)
generateBoard (hit:hits) misses boats = addSquare hit HitSquare (generateBoard hits misses boats)

data Square = HitSquare | MissSquare | BlankSquare | BoatSquare | HaskellSquare deriving (Show, Eq)

newtype Board = Board [[Square]]

instance Show Board where
  show (Board (row:rows)) = 
          "   1 2 3 4 5 6 7 8 9 10\n\n" ++ showRows (row:rows) 0
    where showRows (row:rows) x = [chr (x+65)] ++ "  " ++
            showRow row ++ "\n\n" ++ showRows rows (x+1)
          showRows [] _= ""
          showRow (HitSquare:squares)   = "X " ++ showRow squares
          showRow (MissSquare:squares)  = "O " ++ showRow squares
          showRow (BlankSquare:squares) = "W " ++ showRow squares
          showRow (BoatSquare:squares)  = "B " ++ showRow squares
          showRow (HaskellSquare:squares) = "\\ " ++ showRow squares
          showRow []              = ""
  show (Board [])         = ""


squareAt :: String -> Board -> Maybe Square
squareAt coord (Board arr) = case (getRow coord, getCol coord) of
                         (Just row, Just col) -> Just (arr !! row !! col)
                         _                    -> Nothing

asTuple :: String -> Maybe (Int,Int)
asTuple str = case (getRow str, getCol str) of
                (Just row, Just col) -> Just (row, col)
                _                    -> Nothing

fromTuple :: (Int,Int) -> String
fromTuple (x,y) = ((chr (x+65)):(show (y+1)))

getRow :: String -> Maybe Int
getRow coord
  | length coord /= 2 && length coord /= 3 = Nothing
  | row <= 'J' && row >= 'A' = Just ((fromEnum row) - (fromEnum 'A'))
  | otherwise = Nothing
  where row = head coord

getCol :: String -> Maybe Int
getCol coord
  | length coord /= 2 && length coord /= 3 = Nothing
  | otherwise = case (readMaybe (drop 1 coord) :: Maybe Int)  of
                  Just y -> if (y <= 10 && y >= 1) then Just (y-1) 
                            else Nothing
                  _      -> Nothing

data Orientation = Hor | Vert deriving (Show, Eq)
data BoatName = PatrolBoat | Submarine | Destroyer | Battleship | Haskellship | Carrier deriving (Eq)
instance Show BoatName where
  show PatrolBoat = "Patrol Boat"
  show Submarine = "Submarine"
  show Destroyer = "Destroyer"
  show Battleship = "Battleship"
  show Haskellship = "Haskellship"
  show Carrier = "Carrier"

data Boat = Boat { coords :: [(Int,Int)], name :: BoatName } deriving (Eq)

instance Show Boat where
  show (Boat coords name) = (show name) ++ " at " ++ (show (map fromTuple coords))

showBoats :: [Boat] -> String
showBoats [] = ""
showBoats (boat:boats) = (show boat) ++ "\n" ++ (showBoats boats)

boat :: (Int,Int) -> Int -> Orientation -> BoatName -> Boat
boat origin length orientation = Boat (boatRec origin length orientation)
  where boatRec :: (Int,Int) -> Int -> Orientation -> [(Int,Int)]
        boatRec _ 0 _ = []
        boatRec (x,y) length Hor = ((x,y):boatRec (x,y+1) (length-1) Hor)
        boatRec (x,y) length Vert = ((x,y):boatRec (x+1,y) (length-1) Vert)

patrolBoat origin orientation = boat origin 2 orientation PatrolBoat
submarine origin orientation = boat origin 3 orientation Submarine
destroyer origin orientation = boat origin 3 orientation Destroyer
battleship origin orientation = boat origin 4 orientation Battleship
haskellship origin orientation = boat origin 4 orientation Haskellship
carrier origin orientation = boat origin 5 orientation Carrier

validPlacement :: Boat -> [Boat] -> Bool
validPlacement boat boats = all validSquare (coords boat)
  where validSquare :: (Int,Int) -> Bool
        validSquare (x,y)
          | (x<0)||(x>9)||(y<0)||(y>9) = False
          | otherwise = (x,y) `notElem` (concat (map coords boats))

randomCoord :: IO (Int,Int)
randomCoord = do
  x <- randomRIO (0,9) :: IO Int
  y <- randomRIO (0,9) :: IO Int
  return (x,y)
  
placeBoat :: ((Int,Int) -> Orientation -> Boat) -> [Boat] -> IO [Boat]
placeBoat boatConstructor boats = do
  (x,y) <- randomCoord
  o <- randomRIO (0,1) :: IO Int
  let boat = boatConstructor (x,y) (toOrientation o)
      toOrientation 0 = Hor
      toOrientation 1 = Vert
    in case validPlacement boat boats of
         True -> return (boat:boats)
         False -> placeBoat boatConstructor boats

data PlayerType = Human | Computer deriving (Show, Eq)
data Player = Player { hits :: [(Int,Int)],
                       misses :: [(Int,Int)],
                       ships :: [Boat],
                       playerType :: PlayerType } deriving (Show, Eq)

data Outcome = Hit | Miss | Sunk BoatName | Win BoatName deriving (Show, Eq)

attack :: Player -> (Int,Int) -> Player -> (Outcome, Player)
attack (Player hits misses boats ptype) shot (Player _ _ opponentBoats _) =
  let 
      subset :: (Foldable t, Eq a) => t a -> t a -> Bool
      subset lst1 lst2 = all ((flip elem) lst2) lst1
      attackBoat :: Boat -> Outcome
      attackBoat (Boat coords name)
        | shot `notElem` coords = Miss
        | shot `elem` hits = Hit
        | (shot `elem` coords) && (coords `subset` (shot:hits)) = 
            Sunk name
        | otherwise = Hit
      foldOutcome :: Boat -> Outcome -> Outcome
      foldOutcome boat Miss = attackBoat boat
      foldOutcome _ nonMiss = nonMiss
      foldedOutcome = foldr foldOutcome Miss opponentBoats
      totalPlayer Miss = Player hits (shot:misses) boats ptype
      totalPlayer _    = Player (shot:hits) misses boats ptype
    in case foldedOutcome of
      Sunk name -> if concat (map coords opponentBoats) `subset` 
                        (shot:hits) then (Win name, totalPlayer (Win name))
                   else (Sunk name, totalPlayer (Sunk name))
      nonSunk   -> (nonSunk, totalPlayer nonSunk)

game :: IO ()
game = do
  hShip <- isHaskellShip
  -- putStrLn "Psst... Here's player 2's board"
  -- putStrLn (showBoats boats2)
  let gameLoop :: Player ->  Player -> IO ()
      gameLoop player1@(Player p1hits p1misses p1boats Human) player2@(Player p2hits p2misses _p2boats _p2type)= do
        putStrLn ("Your opponent's board:")
        putStrLn (show (generateBoard p1hits p1misses []))
        putStrLn ("Your board:")
        putStrLn (show (generateBoard p2hits p2misses p1boats))
        putStr "Guess: "
        p1guess <- getLine
        case asTuple p1guess of
          Nothing -> do putStrLn "Invalid guess."
                        gameLoop player1 player2
          Just shot -> let (outcome, newPlayer1) =
                              attack player1 shot player2 in
                         case outcome of
                           Miss -> do putStrLn "Miss."
                                      gameLoop player2 newPlayer1
                           Hit  -> do putStrLn "Hit!"
                                      gameLoop player2 newPlayer1
                           Sunk boatName -> do putStrLn (concat ["You sunk my ", show boatName, "!"])
                                               gameLoop player2 newPlayer1
                           Win boatName -> do putStrLn (concat ["You sunk my ", show boatName, "! You win!"])
                                              if hShip then putStrLn (concat ["\nDr. Gill,\nThank you for teaching me Haskell and JavaScript. ",
                                                                              "I really enjoyed taking your class.\n", 
                                                                              "Here's to the start of a fantastic new journey!\n",
                                                                              "-Andrew"])
                                              else return ()
      gameLoop player1@(Player _ _ _ Computer) player2 = do
        shot <- randomCoord
        putStr ("I guess " ++ (fromTuple shot) ++ ". ")
        let (outcome, newPlayer1) = attack player1 shot player2 in
          case outcome of
            Miss -> do putStrLn "I missed."
                       gameLoop player2 newPlayer1
            Hit -> do putStrLn "I hit!"
                      gameLoop player2 newPlayer1
            Sunk boatName -> do putStrLn ("I sunk your " ++ (show boatName)
                                            ++ "!")
                                gameLoop player2 newPlayer1
            Win boatName -> putStrLn (concat ["I sunk your ", (show boatName),
                                        "! I win!"])
      bship_constructor = if hShip then haskellship else battleship
      ask = do 
              putStr "Do you want me to randomly place your boats for you? (y/N) "
              a <- getLine
              if (a == "y") || (a == "Y") then placeAllBoats [patrolBoat, destroyer, submarine, bship_constructor, carrier] 
              else if (a == "n") || (a == "N") || (a == "") then userPlaceBoats
              else (putStr "Sorry, I didn't get that. ") >> ask
      bship = if hShip then Haskellship else Battleship
      userPlaceBoats :: IO [Boat]
      userPlaceBoats = userPlaceBoatsRec [PatrolBoat, Submarine, Destroyer, bship, Carrier] []
      userPlaceBoatsRec :: [BoatName] -> [Boat] -> IO [Boat]
      userPlaceBoatsRec [] boats = return boats
      userPlaceBoatsRec boatTypes boats = do
        putStrLn ("Your Board:\n" ++ show (generateBoard [] [] boats))
        let prompt = do
                       putStr (concat ["Which boat would you like to place? (",
                                (intercalate ", " (numberBoats boatTypes)),
                                ") "])
                       n <- getLine
                       case (readMaybe n) :: Maybe Int of
                         Nothing -> yell
                         Just choice -> if ((choice < 0) || (choice > length boatTypes)) then yell
                                        else do placedBoat <- pickCoords (boatTypes !! (choice-1)) boats
                                                userPlaceBoatsRec (concat [take (choice-1) boatTypes, drop (choice) boatTypes]) placedBoat
            yell = putStrLn "Please type a number." >> prompt
          in prompt
      numberBoats boatTypes = map (\(n,b) -> concat [show n, ". ", show b]) (zip [1..] boatTypes)
      placeAllBoats :: [((Int,Int) -> Orientation -> Boat)] -> IO [Boat]
      placeAllBoats boatsToPlace = placeAllBoatsRec boatsToPlace []
      placeAllBoatsRec :: [((Int,Int) -> Orientation -> Boat)] -> [Boat] -> IO [Boat]
      placeAllBoatsRec [] boats = return boats
      placeAllBoatsRec boatTypes boats = do
        r <- randomRIO (0, (length boatTypes)-1)
        let boatType = boatTypes !! r
            remainingBoatTypes = (take r boatTypes) ++ (drop (r+1) boatTypes)
          in do 
               recBoats <- placeBoat boatType boats
               placeAllBoatsRec remainingBoatTypes recBoats
     in do
          putStrLn (case hShip of
                      True -> "Welcome to Haskellship! Let's set up your board."
                      False -> "Welcome to Battleship! Let's set up your board.")
          boats1 <- ask
          boats2 <- placeAllBoats [patrolBoat, destroyer, submarine, battleship, carrier] 
          let
            player1 = Player [] [] boats1 Human
            player2 = Player [] [] boats2 Computer
            in gameLoop player1 player2



pickCoords :: BoatName -> [Boat] -> IO [Boat]
pickCoords boatType boats = 
  let constructor = case boatType of PatrolBoat -> patrolBoat
                                     Submarine -> submarine
                                     Destroyer -> destroyer
                                     Battleship -> battleship
                                     Haskellship -> haskellship 
                                     Carrier -> carrier
      yellCoord = (putStrLn "That's not a properly formatted coordinate. Example: 'A10'") >> pickCoords boatType boats
      yellPlacement = (putStrLn "Sorry, you can't put that boat there.") >> pickCoords boatType boats
      pickOrientation :: (Int,Int) -> IO [Boat]
      pickOrientation origin = do
        putStr "Pick 'hor' or 'vert': "
        s <- getLine
        case s of
          "hor" -> checkValidity (constructor origin Hor)
          "vert" -> checkValidity (constructor origin Vert)
          _ -> (putStrLn "Invalid input.") >> pickOrientation origin
      checkValidity boat = case validPlacement boat boats of
                             True -> return (boat:boats)
                             False -> yellPlacement
    in do
      putStr "Pick a leftmost or uppermost coordinate: "
      s <- getLine
      case (asTuple s) of
        Nothing -> yellCoord
        Just origin -> pickOrientation origin

isHaskellShip :: IO Bool
isHaskellShip = do
  progName <- getProgName
  case progName of
    "haskellship" -> return True
    "./haskellship" -> return True
    _             -> return False