2048 game

twentyfortyeight.py

import random


class Board:

    _DIGITS = 4

    def __init__(self, height=4, width=4):
        self.h = height
        self.w = width
        self.board = [[0 for _ in range(self.w)] for _ in range(self.h)]

    # string representation of the board
    def __str__(self):
        width = self.w * (self._DIGITS + 3) + 1
        line = "".join("-" for _ in range(width))
        matrix = []
        for i in range(self.h):
            matrix.append(line)
            cur_line = []
            for j in range(self.w):
                if self.board[i][j] != 0:
                    num = str(self.board[i][j])
                else:
                    num = ""
                spaces = "".join(" " for i in range(self._DIGITS - len(num) + 1))
                cur_line.extend(("- ", num, spaces))
            cur_line.append("-")
            matrix.append("".join(cur_line))
        matrix.append(line)
        return "\n".join(matrix)

    # spawns either a 2 or 4 on a random part of the grid
    def spawn(self):
        positions = [(i, j) for j in range(self.w) for i in range(self.h) if self.board[i][j] == 0]
        assert len(positions) > 0
        square = random.choice(positions)
        value = random.choice((2, 4))
        self.board[square[0]][square[1]] = value

    # returns a boolean for if the game has ended (all squares occupied)
    def ended(self):
        for row in self.board:
            for square in row:
                if square == 0:
                    return False
        return True

    # for the following 4 functions
    # if nothing is moved, return False
    # else, return True

    def move_down(self):
        flag = False
        for j in range(self.w):
            for k in range(self.h, 1, -1):
                cur = 0
                for i in range(k):
                    if self.board[i][j] in (0, cur):
                        flag = True
                        self.board[i][j] += cur
                        if i:
                            self.board[i - 1][j] = 0
                    else:
                        cur = self.board[i][j]
        return flag

    def move_up(self):
        flag = False
        for j in range(self.w):
            for k in range(1, self.h):
                cur = 0
                for i in range(k, -1, -1):
                    if self.board[i][j] in (0, cur):
                        flag = True
                        self.board[i][j] += cur
                        if i < k:
                            self.board[i + 1][j] = 0
                    else:
                        cur = self.board[i][j]
        return flag

    def move_right(self):
        flag = False
        for i in range(self.h):
            for k in range(self.w, 1, -1):
                cur = 0
                for j in range(k):
                    if self.board[i][j] in (0, cur):
                        flag = True
                        self.board[i][j] += cur
                        if j:
                            self.board[i][j - 1] = 0
                    else:
                        cur = self.board[i][j]
        return flag

    def move_left(self):
        flag = False
        for i in range(self.h):
            for k in range(1, self.w):
                cur = 0
                for j in range(k, -1, -1):
                    if self.board[i][j] in (0, cur):
                        flag = True
                        self.board[i][j] += cur
                        if j < k:
                            self.board[i][j + 1] = 0
                    else:
                        cur = self.board[i][j]
        return flag

    def score(self):
        return sum(self.board[i][j] for j in range(self.w) for i in range(self.h))

    @classmethod
    def play_game(cls):

        def print_sep():
            print("---------------------------------")

        cboard = cls()

        def apply(char):
            if char == "U":
                return cboard.move_up()
            elif char == "D":
                return cboard.move_down()
            elif char == "L":
                return cboard.move_left()
            else:
                return cboard.move_right()

        def get_dir():
            prompt = "Please input either U, D, L, or R.\n"
            direction = input(prompt)
            while direction not in ("U", "D", "L", "R"):
                direction = input(prompt)
            return direction

        def apply_move():
            d = get_dir()
            while not apply(d):
                d = get_dir()

        while not cboard.ended():
            cboard.spawn()
            print(cboard)
            print_sep()
            apply_move()
            print_sep()

        print("Your final score is: ", cboard.score())


if __name__ == "__main__":
    Board.play_game()