-- Christos Scordellis (cs62) Informatics
-- Functional Programming Coursework 2 - 17th March 2005
-- In making this submission I declare that my work contains no examples
-- of misconduct, such as plagiarism, collusion or fabrication of results.
module DominoesGame where
import Char
import Dominoes


-- functions that store messages that will be displayed during the game
startM, moveM, numPlayersM, starsM, nextM, chainM, handM, blankM, retryM, errorIn, lazyM :: String 
startM = starsM ++ "\n** Welcome to Huskel's Domino Game. **\n" ++ starsM ++ lazyM
starsM = "**************************************"
moveM = "\nPlease Enter move: "
numPlayersM = "\nPlease enter number of Players: (2-7) \n"
nextM = "\nEnter yout Move: \n"
chainM = "\nChain is: \n"
handM = "\nYour Hand is: \n" 
blankM = "\n\n\n"
retryM = "\nPlease try again.\n>"
errorIn = "\nInvalid Input. \nPlease Try Again with 'a-a' where a is number from 1 to 6 or press Enter to pass: \n"
errorDom = "\n\nDomino not in hand or cannot match chain. Please Try again:\n"
lazyM = "\n-If you feel lazy on entering Dominoes type '?'for autoplay."
anyKeyM = "\nPress 'Enter' see your Hand:\n"
numPlay = "\nPlease enter number of Human Players: (1-6) \n"
randomM = "\nPlease insert a random number between 1 and 900 to shuffle:\n"
-- this will select the highest in score available and valid domino to play. If non-exist it will pass.


dominoesGame :: IO ()
dominoesGame = do 	msg (blankM ++ startM)  
	       		numOfPlayer <- insertNum 2 7 numPlayersM
			rnd <- insertNum 1 900 randomM
			setupGame numOfPlayer rnd
		

-- Setup the game given the number of player and random number		  			
setupGame :: Int -> Int -> IO()
setupGame numOfPlayers rnd = do	let 	(hands,currentP,currentD) = starter numOfPlayers rnd
				msg ("Player " ++ show currentP ++ " has played first domino " ++ show currentD ++ "\n")
				let 	update = firstMove currentP currentD (getHand currentP hands)
		    			chainD = fst update 
		    			newHands = updateHands hands (snd update)
		    			nextP = getHand (turn currentP numOfPlayers) newHands
		    			currentPlayer = fst nextP
				gameLoop currentPlayer numOfPlayers newHands chainD 0
				
-- main loop of the game
-- EndOfFlag game is increased by one each time a player passes, 
-- and set to 0 when a player makes a move with a domino 
-- If that number reaches the number of player then the game is over
-- Also the hand of the current player is checked to discover whether a player has reached 
-- an empty hand. Then the numeric flag is set to a value higher to the value
-- of the players (100) to force the end of game.
gameLoop :: Int -> Int -> [Hand] -> Chain -> EndOfGameFlag -> IO()
gameLoop player players hands chai eog	 | 	eog >= players = do 	msg (gameEnd hands) 
					 				return ()
					 |	otherwise =
		do 	msg (blankM ++ "\r\nPlayer " ++ show player ++ " playing:\n")
			let hnd = getHand player hands
			msg (chainM ++ show chai)
			anyKey
			msg (handM ++ show (snd (hnd)))
			msg nextM
			moveD <-  getMove;
			if (validMove (moveD) hnd chai) then 
				let	(h,g) = playMove (moveD) hnd chai 
				in 
				(gameLoop (turn player players) players (updateHands hands h) g (findWinner h (passPlay moveD eog)))
			 else ( do	msg errorDom 
			 		gameLoop player players hands chai eog)					


-- function that checks whether a players hand is empty
findWinner :: Hand -> EndOfGameFlag -> EndOfGameFlag
findWinner hd eog | (length (snd hd)) == 0 = 100
		  | otherwise = eog 

		
-- function to be used as Press any key to continue
anyKey :: IO ()
anyKey = do 	msg anyKeyM
		c <- getChar
		return ()		


-- insert num checks that a number input is within the parameter bounds
-- it also displays a relevant parameter msg,
-- it recurses until the input is correct

insertNum :: Int -> Int -> String -> IO(Int)
insertNum  x y display = do	msg display
				line <- getLine
	       			let numL = (read line :: Int)
	       			if ((numL < x) || (numL > y)) then (do 	reinsert <- insertNum x y display
									return (reinsert ))
		  			else return (numL) 
					
-- function that gives the number of the next player at each turn
turn :: Int -> Int -> Int
turn pr total | pr == total = 1
	      | otherwise = pr + 1