Python CLI Minesweeper

README.md

CLI Minesweeper

Simple Minesweeper CLI

minesweeper.cli.mp4

How It's Made

Tech Used: Python

This is a simple CLI version of the classic game Minesweeper. The game is played on a grid of squares. Some squares contain mines (bombs), others don't. If a square with a bomb is revealed, the player loses. If no square with a bomb is revealed, a player wins.

The user can input the column and row to choose - the game will then reveal the square. If the square is a bomb, the game ends. If the square is not a bomb, the game will reveal the number of bombs in the surrounding squares. If the number is 0, the game will reveal all the surrounding squares. The user can continue to input coordinates until they reveal a bomb or all the squares that do not contain a bomb.

Optimizations

Adding the ability for users to flag/mark squares that they think contain a bomb, in addition making the game spec-compliant.

Lessons Learned

Writing a responsive and usable 2D CLI game was a fun challenge, ensuring the visual management of the terminal worked across platforms.

minesweeper.py

"""A command line version of Minesweeper"""
import random
import re
import time
from string import ascii_lowercase
import os


def setupgrid(gridsize, start, numberofmines):
    emptygrid = [['0' for i in range(gridsize)] for i in range(gridsize)]

    mines = getmines(emptygrid, start, numberofmines)

    for i, j in mines:
        emptygrid[i][j] = 'X'

    grid = getnumbers(emptygrid)

    return (grid, mines)


def showgrid(grid):
    os.system('clear')
    gridsize = len(grid)

    horizontal = '   ' + (4 * gridsize * '─') + '─'

    # Print top column letters
    toplabel = '     '

    for i in ascii_lowercase[:gridsize]:
        toplabel = toplabel + i + '   '

    print(toplabel + '\n' + horizontal)

    # Print left row numbers
    for idx, i in enumerate(grid):
        row = '{0:2} │'.format(idx + 1)

        for j in i:
            row = row + ' ' + j + ' │'

        print(row + '\n' + horizontal)

    print('')


def getrandomcell(grid):
    gridsize = len(grid)

    a = random.randint(0, gridsize - 1)
    b = random.randint(0, gridsize - 1)

    return (a, b)


def getneighbors(grid, rowno, colno):
    gridsize = len(grid)
    neighbors = []

    for i in range(-1, 2):
        for j in range(-1, 2):
            if i == 0 and j == 0:
                continue
            elif -1 < (rowno + i) < gridsize and -1 < (colno + j) < gridsize:
                neighbors.append((rowno + i, colno + j))

    return neighbors


def getmines(grid, start, numberofmines):
    mines = []
    neighbors = getneighbors(grid, *start)

    for i in range(numberofmines):
        cell = getrandomcell(grid)
        while cell == start or cell in mines or cell in neighbors:
            cell = getrandomcell(grid)
        mines.append(cell)

    return mines


def getnumbers(grid):
    for rowno, row in enumerate(grid):
        for colno, cell in enumerate(row):
            if cell != 'X':
                # Gets the values of the neighbors
                values = [grid[r][c] for r, c in getneighbors(grid,
                                                              rowno, colno)]

                # Counts how many are mines
                grid[rowno][colno] = str(values.count('X'))

    return grid


def showcells(grid, currgrid, rowno, colno):
    # Exit function if the cell was already shown
    if currgrid[rowno][colno] != ' ':
        return

    # Show current cell
    currgrid[rowno][colno] = grid[rowno][colno]

    # Get the neighbors if the cell is empty
    if grid[rowno][colno] == '0':
        for r, c in getneighbors(grid, rowno, colno):
            # Repeat function for each neighbor that doesn't have a flag
            if currgrid[r][c] != 'F':
                showcells(grid, currgrid, r, c)


def playagain():
    choice = input('Play again? (y/n): ')

    return choice.lower() == 'y'


def parseinput(inputstring, gridsize, helpmessage):
    cell = ()
    flag = False
    message = "Invalid cell. " + helpmessage

    pattern = r'([a-{}])([0-9]+)(f?)'.format(ascii_lowercase[gridsize - 1])
    validinput = re.match(pattern, inputstring)

    if inputstring == 'help':
        message = helpmessage

    elif validinput:
        rowno = int(validinput.group(2)) - 1
        colno = ascii_lowercase.index(validinput.group(1))
        flag = bool(validinput.group(3))

        if -1 < rowno < gridsize:
            cell = (rowno, colno)
            message = ''

    return {'cell': cell, 'flag': flag, 'message': message}


def playgame():
    gridsize = 9
    numberofmines = 10

    currgrid = [[' ' for i in range(gridsize)] for i in range(gridsize)]

    grid = []
    flags = []
    starttime = 0

    helpmessage = ("Type the column followed by the row (eg. a5). "
                   "To put or remove a flag, add 'f' to the cell (eg. a5f).")

    showgrid(currgrid)
    print(helpmessage + " Type 'help' to show this message again.\n")

    while True:
        minesleft = numberofmines - len(flags)
        prompt = input('Enter the cell ({} mines left): '.format(minesleft))
        result = parseinput(prompt, gridsize, helpmessage + '\n')

        message = result['message']
        cell = result['cell']

        if cell:
            print('\n\n')
            rowno, colno = cell
            currcell = currgrid[rowno][colno]
            flag = result['flag']

            if not grid:
                grid, mines = setupgrid(gridsize, cell, numberofmines)
            if not starttime:
                starttime = time.time()

            if flag:
                # Add a flag if the cell is empty
                if currcell == ' ':
                    currgrid[rowno][colno] = 'F'
                    flags.append(cell)
                # Remove the flag if there is one
                elif currcell == 'F':
                    currgrid[rowno][colno] = ' '
                    flags.remove(cell)
                else:
                    message = 'Cannot put a flag there'

            # If there is a flag there, show a message
            elif cell in flags:
                message = 'There is a flag there'

            elif grid[rowno][colno] == 'X':
                print('Game Over\n')
                showgrid(grid)
                if playagain():
                    playgame()
                return

            elif currcell == ' ':
                showcells(grid, currgrid, rowno, colno)

            else:
                message = "That cell is already shown"

            if set(flags) == set(mines):
                minutes, seconds = divmod(int(time.time() - starttime), 60)
                print(
                    'You Win. '
                    'It took you {} minutes and {} seconds.\n'.format(minutes,
                                                                      seconds))
                showgrid(grid)
                if playagain():
                    playgame()
                return

        showgrid(currgrid)
        print(message)

playgame()