buildTree:: Board->Color->Tree Board
buildTree board color = Node board (Prelude.map (\board -> (buildTree board oppositeColor)) possibleBoards)
    where
        getListOfBoards _ _ [] = []
        getListOfBoards (Board b) color (x:xs) =[addToBoard (Board b) x color] ++ (getListOfBoards (Board b) color xs)
        oppositeColor = (negateColor color)
        possibleCoordinates = possibleMoves board
        possibleBoards = getListOfBoards board color possibleCoordinates

minmaxAlfa:: [Tree Board]->Color->Int->Int->Int->Int->Int
minmaxAlfa [] color level maxLevel alfa beta = alfa
minmaxAlfa (x:xs) color level maxLevel alfa beta
    | (newAlfa>=beta) = beta
    | otherwise  = minmaxAlfa xs color level maxLevel newAlfa beta
    where
        newAlfa = max alfa (exploreTree x color level maxLevel alfa beta)

minmaxBeta:: [Tree Board]->Color->Int->Int->Int->Int->Int
minmaxBeta [] color level maxLevel alfa beta = beta
minmaxBeta (x:xs) color level maxLevel alfa beta
    | (alfa >= newBeta) = alfa
    | otherwise = minmaxBeta xs color level maxLevel alfa newBeta
    where
        newBeta = min beta (exploreTree x color level maxLevel alfa beta)

exploreTree:: Tree Board->Color->Int->Int->Int->Int->Int
exploreTree (Node node children) color level maxLevel alfa beta
    | Prelude.null children = rateBoard node color
    | level==maxLevel = minimum (rateBoards children color)
    | level `mod` 2 == 0 = minmaxAlfa children color (level+1) maxLevel alfa beta
    | otherwise = minmaxBeta children color (level+1) maxLevel alfa beta

minmax:: Tree Board->Color->Int->Int
minmax (Node node children) color maxLevel = exploreTree (Node node children) color 0 maxLevel (-1000) 1000