import pygame
from pygame.sprite import Sprite

class Bazi(Sprite):
    """创建一个代表靶子的类."""

    def __init__(self, ai_settings, screen):
        """初始化靶子，并设置其起始位置"""
        super(Bazi, self).__init__()
        self.screen = screen
        self.ai_settings = ai_settings

        # 加载外来图像，并设置其rect属性
        self.image = pygame.image.load('images/bazi.png')
        self.rect = self.image.get_rect()

        # 在屏幕左上角启动每个新靶子
        self.rect.x = self.rect.width
        self.rect.y = self.rect.height

        # 存储靶子的准确位置
        self.x = float(self.rect.x)
        
    def check_edges(self):
        """如果靶子在屏幕边缘，则返回True。"""
        screen_rect = self.screen.get_rect()
        if self.rect.right >= screen_rect.right:
            return True
        elif self.rect.left <= 0:
            return True
        
    def update(self):
        """靶子的移动（向左或者向右）"""
        self.x += (self.ai_settings.bazi_speed_factor *
                        self.ai_settings.fleet_direction)
        self.rect.x = self.x

    def blitme(self):
        """在当前位置绘制靶子"""
        self.screen.blit(self.image, self.rect)