#!/usr/bin/env python
from pos import TwoDPos

class BoardTools:
    def __init__(self):
        pass

    def winning(self, b):
        for i in range(3):
            if b[i][0] == b[i][1] == b[i][2]:
                if b[i][0] != Board.unplayed:
                    return b[i][0]
            if b[0][i] == b[1][i] == b[2][i]:
                if b[0][i] != Board.unplayed:
                    return b[0][i]
        if b[0][0] == b[1][1] == b[2][2]:
            if b[0][0] != Board.unplayed:
                return b[0][0]
        if b[2][0] == b[1][1] == b[0][2]:
            if b[2][0] != Board.unplayed:
                return b[2][0]
        return Board.unplayed

class Board:
    unplayed = 0
    cross = 1
    nought = 2

    def __init__(self):
        self.board = [
                [
                    [
                        [Board.unplayed for i in range(3)]
                        for j in range(3)
                    ]
                    for k in range(3)
                ]
                for l in range(3)
        ]
        self.moves = []
        self.turn = Board.cross

    def set(self, a, b, c, d, val):
        self.board[a][b][c][d] = val

    def get(self, a, b, c, d):
        return self.board[a][b][c][d]

    def alternate(self):
        if self.turn == Board.cross:
            self.turn = Board.nought
        else:
            self.turn = Board.cross

    def subWin(self, x, y):
        return BoardTools.winning(None, self.board[x][y])

    def metaboard(self):
        return [[BoardTools.winning(None, self.board[x][y]) for x in range(3)] for y in range(3)]

    def win(self):
        return BoardTools.winning(self.metaboard())

    def append(self, move):
        self.moves.append(move)
        self.set(*move.local(), self.turn)
        self.alternate()

    def reachableEmpty(self):
        metaboard = self.metaboard()
        buf = []
        for i in range(3):
            for j in range(3):
                if metaboard[i][j] == Board.unplayed:
                    for k in range(3):
                        for l in range(3):
                            buf.append(TwoDPos(TwoDPos.l, (i, j, k, l)))
        return buf

    def possible(self):
        try:
            move = self.moves[-1]
        except IndexError:
            buf = []
            for i in range(3):
                for j in range(3):
                    for k in range(3):
                        for l in range(3):
                            buf.append(TwoDPos(TwoDPos.l, (i, j, k, l)))

            return buf

        local = move.local()
        if self.subWin(local[2], local[3]):
            return self.reachableEmpty()

        buf = []
        for i in range(3):
            for j in range(3):
                if self.board[local[2]][local[3]][i][j] == Board.unplayed:
                    buf.append(TwoDPos(TwoDPos.l, (local[2], local[3], i, j)))

        return buf