Simple modal game demo

modal_game.py

# Simple example of a game with multiple modes.
# THe only dependency is pygame-ce.
# This code is in the public domain.
# Use it as you see fit.

import random
import pygame

pygame.init()
screen = pygame.display.set_mode((720, 720))
clock = pygame.time.Clock()
font = pygame.font.Font(None, 48)

running = True

keystrokes = (
    (pygame.K_a, "a"),
    (pygame.K_s, "s"),
    (pygame.K_d, "d"),
    (pygame.K_f, "f"),
)


class Game:
    def __init__(self):
        self.mode = self.mode_boot
        self.score = 0
        self.timer = 0
        self.key, self.letter = "", None
        self.set_text("LetterMatcher: Press Space To Begin")
        self.bg_color = "purple"

    def set_text(self, text=None):
        if text:
            self.text = font.render(text, True, (10, 10, 10))
        self.prompt = font.render(self.letter, True, (10, 10, 10))
        self.score_text = font.render(f"Score: {self.score}", True, (10, 10, 10))

    def draw(self):
        screen.fill(self.bg_color)
        screen.blit(self.text, (64, 64))
        screen.blit(self.prompt, (64, 192))
        screen.blit(self.score_text, (64, 256))
        if self.timer:
            pygame.draw.rect(
                screen, "orange", pygame.Rect(64, 100, (self.timer * 4), 64)
            )

    def set_challenge(self):
        self.key, self.letter = random.choice(keystrokes)
        self.timer = 60

    def start_game(self):
        self.score = 0
        self.set_challenge()
        self.set_text("Press The Key That Matches")
        self.mode = self.mode_play

    def end_game(self, key=None):
        self.mode = self.mode_game_over
        self.set_text("Game Over. Press Space To Play Again")
        if key:
            self.prompt = font.render(
                    f"You pressed {pygame.key.name(key.key)}, not {pygame.key.name(self.key)}", True, (10, 10, 10))

    # Game modes

    def mode_boot(self, key):
        self.bg_color = "purple"
        if key and key.key == pygame.K_SPACE:
            self.start_game()

    def mode_play(self, key):
        self.bg_color = "pink"

        self.timer -= 1

        if not self.timer:
            self.end_game()

        if key:
            if key.key == self.key:
                self.set_challenge()
                self.score += 1
                self.set_text()
            else:
                self.end_game(key)

    def mode_game_over(self, key):
        self.bg_color = "green"

        if key and key.key == pygame.K_SPACE:
            self.start_game()


game = Game()

while running:
    key = None
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        if event.type == pygame.KEYDOWN:
            key = event

    game.mode(key)
    game.draw()

    pygame.display.flip()

    clock.tick(60)  # limits FPS to 60

pygame.quit()