snake.py

from tkinter import *
import random

GAME_WIDTH = 1000
GAME_HEIGHT = 600
SPEED = 80
SPACE_SIZE = 25
FOOD_COLOR = "#dddddd"
SNAKE_COLOR = "#6759e0"
BODY_PARTS = 5
BACKGROUND_COLOR = "#1F1F1F"


class Snake:
    def __init__(self):
        self.body_size = BODY_PARTS
        self.coordinates = []
        self.squares = []

        for i in range(0, BODY_PARTS):
            self.coordinates.append([0, 0])

        for x, y in self.coordinates:
            square = canvas.create_rectangle(
                x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill=SNAKE_COLOR, tag="snake"
            )
            self.squares.append(square)


class Food:
    def __init__(self):
        x = random.randint(0, (GAME_WIDTH // SPACE_SIZE) - 1) * SPACE_SIZE
        y = random.randint(0, (GAME_HEIGHT // SPACE_SIZE) - 1) * SPACE_SIZE
        self.coordinates = [x, y]
        canvas.create_oval(
            x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill=FOOD_COLOR, tag="food"
        )


def next_turn(snake, food):
    if paused:
        return

    x, y = snake.coordinates[0]
    if direction == "up":
        y -= SPACE_SIZE
    elif direction == "right":
        x += SPACE_SIZE
    elif direction == "left":
        x -= SPACE_SIZE
    elif direction == "down":
        y += SPACE_SIZE

    snake.coordinates.insert(0, (x, y))
    square = canvas.create_rectangle(
        x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill="#5747eb"
    )
    snake.squares.insert(0, square)

    if x == food.coordinates[0] and y == food.coordinates[1]:
        global score
        score += 20
        label.config(text="Score : {}".format(score))
        canvas.delete("food")
        food = Food()
    else:
        del snake.coordinates[-1]
        canvas.delete(snake.squares[-1])
        del snake.squares[-1]

    if check_collisions(snake):
        game_over()
    else:
        window.after(SPEED, next_turn, snake, food)


def toggle_pause(event=None):
    global paused
    if game_over_state:
        return
    if paused:
        paused = False
        canvas.delete("pause_text")
        next_turn(snake, food)
    else:
        paused = True
        canvas.create_text(
            canvas.winfo_width() / 2,
            canvas.winfo_height() / 2,
            font=("Consolas", 50),
            text="PAUSED",
            fill="#aaaaaa",
            tag="pause_text",
        )


def change_direction(new_direction):
    global direction

    if new_direction == "left":
        if direction != "right":
            direction = new_direction

    if new_direction == "right":
        if direction != "left":
            direction = new_direction

    if new_direction == "up":
        if direction != "down":
            direction = new_direction

    if new_direction == "down":
        if direction != "up":
            direction = new_direction


def check_collisions(snake):
    x, y = snake.coordinates[0]

    if x < 0 or x >= GAME_WIDTH:
        return True

    elif y < 0 or y >= GAME_HEIGHT:
        return True

    for body_part in snake.coordinates[1:]:
        if x == body_part[0] and y == body_part[1]:
            return True
    return False


def game_over():
    global game_over_state
    game_over_state = True
    canvas.delete(ALL)
    canvas.create_text(
        canvas.winfo_width() / 2,
        (canvas.winfo_height() / 2) - 40,
        font=("Consolas", 60),
        text="GAME OVER",
        fill="#DB4242",
        tag="gameover",
    )
    replay_btn = Button(
        window,
        text="Restart",
        font=("Consolas", 20),
        bg="#5d4fe0",
        fg="white",
        bd=0,
        padx=20,
        pady=10,
        command=restart,
    )
    canvas.create_window(
        canvas.winfo_width() / 2, canvas.winfo_height() / 2 + 40, window=replay_btn
    )


def restart():
    global snake, food, score, direction, paused, game_over_state
    score = 0
    direction = "down"
    paused = False
    game_over_state = False
    label.config(text="Score : {}".format(score))
    canvas.delete(ALL)
    snake = Snake()
    food = Food()
    next_turn(snake, food)


window = Tk()
window.title("Snake game")
window.resizable(False, False)

score = 0
direction = "down"
paused = False
game_over_state = False

label = Label(window, text="Score : {}".format(score), font=("monospace", 35))
label.pack()

canvas = Canvas(window, bg=BACKGROUND_COLOR, height=GAME_HEIGHT, width=GAME_WIDTH)
canvas.pack()

window.update_idletasks()
x = (window.winfo_screenwidth() // 2) - (window.winfo_width() // 2)
y = (window.winfo_screenheight() // 2) - (window.winfo_height() // 2)
window.geometry(f"+{x}+{y}")


def on_any_key(event):
    if game_over_state:
        restart()
    elif paused:
        toggle_pause()


window.bind("<Left>", lambda event: change_direction("left"))
window.bind("<Right>", lambda event: change_direction("right"))
window.bind("<Up>", lambda event: change_direction("up"))
window.bind("<Down>", lambda event: change_direction("down"))
window.bind("p", toggle_pause)
window.bind("<KeyPress>", on_any_key)

snake = Snake()
food = Food()

next_turn(snake, food)

window.mainloop()