cassidoo-20191223

snake.py

# Make the game Snake. Be as creative (or not) as you want!

import curses
import signal
from curses import wrapper
import math
import random

screenWidth = 80

class boardLocation:
    def __init__(self, row, col, direction):
        self.row = row
        self.col = col
        self.direction = direction

def drawSnake(snakeBody, snakeLength, fruit):
    ateFruit = False
    gameOver = False
    pieceOfFruit = fruit[0]
    # trim tail to match current length of snake
    if len(snakeBody) > snakeLength:
        snakeBody.pop(0)

    for segment in snakeBody:
        stdscr.addch(segment.row, segment.col, "S")
        # did the snake eat the fruit?
        if segment.row == pieceOfFruit.row and segment.col == pieceOfFruit.col:
            ateFruit = True
            nextFruitRow, nextFruitCol = findSafeFruitPlace(snakeBody, fruit)
            fruit.append(boardLocation(nextFruitRow, nextFruitCol, 'X'))
            fruit.pop(0)
            break
        # did the snake hit its own body?
        for restOfBody in snakeBody:
            if segment != restOfBody:
                if segment.row == restOfBody.row and segment.col == restOfBody.col:
                    gameOver = True
        # did the snake hit a wall?
        if segment.row == 0 or segment.row == LINES or segment.col == 0 or segment.col >= screenWidth - 1:
            gameOver = True

    return ateFruit, gameOver

def findSafeFruitPlace(snakeBody, fruit):
    while True:
        # put next fruit in random locaiton, but not where snake exists
        randomRow = random.randint(1, LINES - 1)
        randomCol = random.randint(1, screenWidth - 2)
        safePlaceForFruit = True
        for segment in snakeBody:
            if randomRow == segment.row and randomCol == segment.col:
                safePlaceForFruit = False
        if safePlaceForFruit:
            break
    return randomRow, randomCol

def drawFruit(fruit):
    for segment in fruit:
        stdscr.addch(segment.row, segment.col, "F")
    return

def drawBoard(snakeBody, snakeLength, fruit):
    stdscr.clear()
    stdscr.addstr(0, 0, "=" * screenWidth)
    stdscr.addstr(LINES - 1, 0, "=" * screenWidth)
    for l in range(0, LINES):
        stdscr.addstr(l, 0, "=")
        stdscr.addstr(l, screenWidth - 1, "=")
    stdscr.move(0, 0)
    drawFruit(fruit)
    ateFruit, gameOver = drawSnake(snakeBody, snakeLength, fruit)
    stdscr.refresh()
    return ateFruit, gameOver

def main(stdscr):

    snakeLength = 20
    snakeIncrease = 20

    row = math.floor(LINES / 2)
    col = 40
    direction = 'R'

    snakeBody = []
    snakeBody.append(boardLocation(row, col, direction))

    fruit = []
    nextFruitRow, nextFruitCol = findSafeFruitPlace(snakeBody, fruit)
    fruit.append(boardLocation(nextFruitRow, nextFruitCol, 'X'))

    ateFruit, gameOver = drawBoard(snakeBody, snakeLength, fruit)

    while True:
        TIMEOUT = 1
        signal.alarm(TIMEOUT)
        try:
            c = stdscr.getch()
            if c == ord('a'):
                direction = 'L'
            elif c == ord('d'):
                direction = 'R'
            elif c == ord('w'):
                direction = 'U'
            elif c == ord('s'):
                direction = 'D'
            elif c == ord('q'):
                break  # Exit the while loop
            if direction == 'L':
                col = col - 1
            elif direction == 'R':
                col = col + 1
            elif direction == 'U':
                row = row - 1
            elif direction == 'D':
                row = row + 1
            snakeBody.append(boardLocation(row, col, direction))
        except:
            c = ''
        signal.alarm(0)

        # if border wall is breached, break
        # if row == 0 or row == LINES or col == 0 or col >= screenWidth - 1:
        #     break

        ateFruit, gameOver = drawBoard(snakeBody, snakeLength, fruit)
        if gameOver:
            break
        if ateFruit:
            snakeLength += snakeIncrease
            ateFruit = False


print('snake controls')
print('w - up     a - left')
print('s - down   d - right')
print('q - quit')

input("Press Enter to start...")

# set up curses
stdscr = curses.initscr()
LINES = curses.LINES
curses.noecho()
curses.cbreak()
curses.curs_set(0)
stdscr.keypad(True)

# keep a Ctrl-C from hosing your terminal session
def empty_handler(): 
    return

signal.signal(signal.SIGALRM, empty_handler)

wrapper(main)

# tear down curses
curses.curs_set(1)
curses.nocbreak()
stdscr.keypad(False)
curses.echo()
curses.endwin()