mistercam

(defn initialize-board [] 
  "Creates a new reversi game board" 
  [[nil nil nil nil nil nil nil nil]
   [nil nil nil nil nil nil nil nil]
   [nil nil nil nil nil nil nil nil]
   [nil nil nil :w  :b  nil nil nil]
   [nil nil nil :b  :w  nil nil nil]
   [nil nil nil nil nil nil nil nil]
   [nil nil nil nil nil nil nil nil]
   [nil nil nil nil nil nil nil nil]])

mistercam

(def directions
  {:N [-1 0] :NE [-1 1] :E [0 1] :SE [1 1] :S [1 0] :SW [1 -1] :W [0 -1] :NW [-1 -1]})

(defn move-valid? [board piece move]
  "Returns true if the specified move for the specified piece will cause
  a piece to be flipped in any direction."
  (let [r (move 0) c (move 1)]
    (cond
      (or (> r 7) (< r 0) (> c 7) (< c 0)) nil
      (not= nil ((board r) c)) nil

mistercam

(defn valid-moves [board piece]
  "Returns the set of valid moves for the given piece"
  (for [r (range 8) c (range 8) ; for each permutation of r and c
        :let [move [r c]]
        :when (move-valid? board piece move)]
    move))

(defn game-over? [board]
  "Returns true if there are no more moves to be made on the board, else returns false"
  (and

mistercam

(defn count-pieces [board piece]
  "Returns the number of squares occupied by the specified piece"
  (count (filter #(= % piece) (flatten board))))

(defn winner [board]
  "Returns the winner, or nil if there's a tie"
  (let [w (count-pieces board :w ) b (count-pieces board :b )]
    (cond
      (> w b) :w (> b w) :b :else nil)))

mistercam

(defn flip [board piece move direction]
  "Returns a new board with results of playing the specified move and piece"
  (if (flippable? board piece move direction)
    (loop [b board m (vec (map + move direction))] ; bind board to b so we can use it in recur
      (let [r (m 0)
            c (m 1)
            p ((board r) c)]
        (if (= p piece)
          b ; we've come to a piece the same colour as the active piece, so we're done flipping. Return the modified board.
          (recur (assoc b r (assoc (b r) c piece)) (vec (map + m direction)))))) ; more flipping to be done, so flip and recur.

mistercam

(defn opposite-piece [piece]
  "Returns the opposing-piece of the specified piece"
  (if (= :w piece) :b :w ))

mistercam

(def columns
  {"A" 0 "B" 1 "C" 2 "D" 3 "E" 4 "F" 5 "G" 6 "H" 7})

(defn print-cols [row]
  "Prints the contents of the each square in the specified row to standard
  out."
  (if (not (empty? row))
    (let [c (first row)]
      (cond
        (= :w c) (print "W")

mistercam

(defn malformed-input? [input]
  "Returns true if the input is valid, otherwise false."
  (not (re-find (re-matcher #"^([0-7][A-Ha-h])$|^([A-Ha-h][0-7])$" input))))

(defn parse-input [input]
  "Converts the user input into a coordinate vector"
  (let [f (str (first input)) l (str (last input))]
    (if (Character/isDigit (first input))
      [(Integer/parseInt f) (columns (string/upper-case l))] ; e.g 2E
      [(Integer/parseInt l) (columns (string/upper-case f))]))) ; e.g E2

mistercam

(defn prompt-for-move [piece board]
  "Prompts the user for a move. Returns the move, if-valid. Returns nil
  if user has quit."
  (loop [input (atom "")]
    (if (= :w piece) ; Prints an input prompt
      (print "White's Turn. Enter move: ")
      (print "Black's Turn. Enter move: "))
    (flush) ; We printed the prompt with a 'print' instead of 'println'. Flushing forces the prompt to appear.
    (reset! input (str (read-line))) ; Read input and store back into 'input'
    (cond

mistercam

(defn print-winner [board]
  "Prints game over to standard out and declares the winner"
  (let [p (winner board)] ; 'p' is the piece with the most coverage
    (cond
      (= p :b ) (println "Game over. Black Wins!")
      (= p :w ) (println "Game over. White Wins!")
      :else (println "Game over. Tie!"))))

(defn reversi-text []
  "Starts a text-based Reversi game."