import pygame
from .. import tools,setup
from .. import constants as C

class FlashingCoin(pygame.sprite.Sprite):  # 继承pygame精灵类
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.frames = []
        self.frame_index = 0
        frame_rects = [(1,160,5,8),(9,160,5,8),(17,160,5,8),(9,160,5,8)]   # 闪烁
        self.load_frames(frame_rects)
        self.image = self.frames[self.frame_index]  # 使用图片第一帧数
        self.rect = self.image.get_rect()
        self.rect.x = 280
        self.rect.y = 58
        self.timer = 0  # 随游戏切换金币帧

    def load_frames(self,frame_rects):
        sheet = setup.GRAPHICS['item_objects']
        for frame_rect in frame_rects:
            self.frames.append(tools.get_image(sheet,*frame_rect,(0,0,0), C.BG_MULTI))


    def update(self):
        self.current_time = pygame.time.get_ticks()
        frame_durations = [375,125,125,125]  # 每图片帧数时间

        if self.timer == 0:
            self.timer = self.current_time # 如果初始时间为零改为当前时间
        elif self.current_time - self.timer > frame_durations[self.frame_index]:  # 此时时间-计时器时间>所在帧应有时间间隔
            self.frame_index += 1
            self.frame_index %= 4
            self.timer = self.current_time  # 没交换一次计时器时间调成当下时间

        self.image = self.frames[self.frame_index]