snake_game.py

##============================================================##
##                                                            ##
##                  Ujjwal Gupta                              ##
##                   Snake Game                               ##
##          https://github.com/ujjwalgupta07                  ##
##                                                            ##
##============================================================##


from random import randrange
import turtle

# initial heading of turtle is in east (Angle 90 in "logo" mode is east)
heading = [90]

# A list to store the postion of snake
position = []

# 0 = Food unavailable
# 1 = Fodd available
food_available = [0]

# To track the score
score = [0]

# Food co-ordinates
food_cor = [0, 0]

# Game
game_no = [0]

# Home (This function will be run first everytime a new game will start)


def home(x=0, y=0):
    turtle.clearscreen()                  # To clear the whole screen for a new game
    heading[0] = 90
    position.clear()
    food_available[0] = 0
    score[0] = 0
    food_cor[0] = 0
    food_cor[1] = 0
    turtle.mode("logo")                   # Set the turtle in mode "logo"
    turtle.setheading(heading[0])
    turtle.clear()
    turtle.up()
    turtle.hideturtle()                   # To make the turtle invisible
    turtle.title("Snake Game")            # Title of the window screen
    turtle.goto(0, 0)
    turtle.write("PLAY", align="center", font=("Arial", 15, "normal"))
    turtle.onscreenclick(start)           # Call the function start after a click on screen
    turtle.onkey(start,'space')
    turtle.done()


# To draw the outer box for the arena
def outer_box():
    turtle.clear()
    turtle.hideturtle()
    turtle.shape("square")
    turtle.speed(0)                       # Set the speed of the turtle fastest
    turtle.width(3)
    turtle.up()
    turtle.goto(332, -278)
    turtle.down()
    for i in range(2):
        turtle.left(90)
        turtle.fd(278.5*2)
        turtle.left(90)
        turtle.fd(334*2)
    turtle.up()
    turtle.goto(0, 0)
    turtle.width(1)
    turtle.speed(1)                       # Set the speed of the turtle slowest for playing the snake game


def start(x=0, y=0):
    turtle.onscreenclick(None)            # To reset the previos onscreenclick command (line 51)
    turtle.onkey(None,'space')
    x = y = 0

    outer_box()

    # Make a new turtle for food
    food_turtle = turtle.Turtle()
    food_turtle.hideturtle()
    food_turtle.up()
    food_turtle.shape("square")
    food_turtle.speed(0)
    food_turtle.color("blue")

    # Make a new turtle for score
    score_turtle = turtle.Turtle()
    score_turtle.hideturtle()
    score_turtle.up()
    score_turtle.speed(0)
    score_turtle.color("#770606")
    score_turtle.goto(291, -278)
    score_turtle.write(
        "Score: {}".format(score[0]), align="center", font=("Arial", 15, "normal"))

    # Boundary condition for snake to touch the outer box
    while x > -332 and x < 332 and y > -278 and y < 278:
        global food_available
        if food_available[0] == 0:
            food(food_turtle)
            food_available[0] = 1

        # To set the commands for arrow keys
        turtle.onkey(up, "Up")
        turtle.onkey(down, "Down")
        turtle.onkey(left, "Left")
        turtle.onkey(right, "Right")
        turtle.listen()
        move()
        x = turtle.xcor()
        y = turtle.ycor()

        # Boundary condition for snake to eat the food
        if x - food_cor[0] < 5 and x - food_cor[0] > -5 and y - food_cor[1] < 5 and y - food_cor[1] > -5:
            food_available[0] = 0
            food_turtle.clear()
            score[0] += 1
            score_turtle.clear()
            score_turtle.write(
                "Score: {}".format(score[0]), align="center", font=("Arial", 15, "normal"))

        # Boundary condition for snake to collide with itself
        for i in range(len(position)):
            if x - position[i][0] < 5 and x - position[i][0] > -5 and y - position[i][1] < 5 and y - position[i][1] > -5:
                score_turtle.clear()
                food_turtle.clear()
                game_over()

    score_turtle.clear()
    food_turtle.clear()
    game_over()


# define the different function of arrow keys
def up(): heading[0] = 180 if heading[0] == 180 else 0


def down(): heading[0] = 0 if heading[0] == 0 else 180


def left(): heading[0] = 90 if heading[0] == 90 else 270


def right(): heading[0] = 270 if heading[0] == 270 else 90


# To create the food
def food(food_turtle):
    x = randrange(-15, 15)
    y = randrange(-12, 12)

    # The co-ordinates are multiplied with 20 so that the snake and food can be in same line
    # If co-ordinates of food will be like 211,121 then the snake and food will not be in the same line
    food_cor[0] = x*20
    food_cor[1] = y*20
    food_turtle.hideturtle()
    food_turtle.up()
    food_turtle.goto(food_cor)
    food_turtle.stamp()


# To move the snake
def move():
    turtle.setheading(heading[0])
    turtle.up()
    turtle.stamp()
    position.append(turtle.position())

    # Turtle's stamp size is 20
    # So before creating another stamp move forward 20
    turtle.fd(20)

    # Boundary conditio to check the length of snake is not more than the score + 1
    if score[0] + 1 < len(position):
        turtle.clearstamps(1)
        position.pop(0)


# Function for the game over
def game_over():
    turtle.onscreenclick(None)
    turtle.speed(0)
    game_no[0] += 1
    print("Your {} game score was : {}".format(game_no[0],score[0]))
    turtle.clear()
    turtle.hideturtle()
    turtle.up()
    turtle.color("red")
    turtle.goto(0, 175)
    turtle.write("Game Over", align="center", font=("Arial", 15, "normal"))
    turtle.goto(0, 125)
    turtle.write("Score: {}".format(score[0]),
                 align="center", font=("Arial", 15, "normal"))
    high_score()
    turtle.goto(0, -125)
    turtle.write("Click Anywhere on the screen or press \"Space\" key to go to main menu",
                 align="center", font=("Arial", 15, "normal"))
    turtle.goto(0, -175)
    turtle.write("Press 'q' to exit the game.",
                 align="center", font=("Arial", 15, "normal"))
    turtle.color("black")
    turtle.onscreenclick(home)
    turtle.onkey(home, "space")
    turtle.onkey(exit, "q")
    turtle.done()


# Function to write the high score on the screen and save it in the file high_score.txt
def high_score():
    try:
        with open(".high_score.txt", "r+") as f:
            data = int(f.read())
            if data < score[0]:
                data = score[0]
                f.seek(0)
                f.write(str(data))
                f.truncate()

            turtle.goto(0, 100)
            turtle.write("High Score: {}".format(data),
                         align="center", font=("Arial", 15, "normal"))
            turtle.goto(0, 75)
            turtle.write("To reset the high score press ' r ' key",
                         align="center", font=("Arial", 15, "normal"))
            turtle.onkey(high_reset, 'r')

    except FileNotFoundError:
    	with open(".high_score.txt",'w') as f:
    		f.write(str(score[0]))


# To reset the high score
def high_reset():
	turtle.onkey(None, 'r')
	data = 0
	with open(".high_score.txt", "r+") as f:
	    f.seek(0)
	    f.write(str(data))
	    f.truncate()
	turtle.goto(0, 0)
	turtle.write("High Score has been reset",
	             align="center", font=("Arial", 15, "normal"))


# To exit the program
def exit():
    print("Thank you for playing the game :)")
    quit()


# To start the whole game
home(0, 0)
print("Thank you for playing the game :)")