from random import randint
from tkinter import *

class Randball():
  def __init__(self,canvas,scrnwidth,scrnheight):
    #初始化畫布
    self.canvas = canvas
    #初始化球的圓心坐標
    self.x_pos = randint(50,int(scrnwidth))#X軸的坐標 randint 隨機產生一個范圍內的整數
    self.y_pos = randint(50,int(scrnheight))#Y軸的坐標
    #球的移動距離
    self.x_move = 10
    self.y_move = 10
    #整個屏幕的高和寬
    self.scrnwidth =scrnwidth
    self.scrnheight =scrnheight
    #初始化球的半徑
    self.randius = randint(10,80)
    #隨機產生球的顏色
    rc = lambda : randint(0,255)
    self.color = '#%02x%02x%02x'%(rc(),rc(),rc())
  def create_ball(self):
    #計算得到用于創(chuàng)建球的四個坐標
    x1 = self.x_pos - self.randius
    y1 = self.y_pos - self.randius
    x2 = self.x_pos + self.randius
    y2 = self.y_pos + self.randius
    #畫球
    self.item =self.canvas.create_oval(x1,y1,x2,y2,fill = self.color,outline = self.color)

  def move_ball(self):
    #球按照指定距離移動，如果碰到障礙就向相反的方向運動
    self.x_pos += self.x_move
    self.y_pos += self.y_move
    if self.x_pos >= self.scrnwidth - self.randius:
      self.x_move = -self.x_move
    elif self.y_pos >= self.scrnheight - self.randius:
      self.y_move = -self.y_move
    elif self.x_pos < self.randius:
      self.x_move = abs(self.x_move)
    elif self.y_pos < self.randius:
      self.y_move = abs(self.y_move)
    self.canvas.move(self.item,self.x_move,self.y_move)


class Screensaver():
  balls = []
  def __init__(self,ball_nums):
    self.win = Tk()
    self.width = self.win.winfo_screenwidth()
    self.height = self.win.winfo_screenheight()
    self.win.overrideredirect(True)
    self.win.attributes('-alpha',1)
    #綁定事件，有任何動作退出屏保
    self.win.bind('<Any-Button>',self.exit_screensaver)
    self.win.bind('<Motion>',self.exit_screensaver )
    self.canvas = Canvas(self.win,width = self.width,height = self.height,bg="#FFFFFF")#背景 顏色自己隨便調整，至于啥顏色就看自己的心情了
    self.canvas.pack()


    for i in range(0,ball_nums):
        ball = Randball(self.canvas,scrnwidth=self.width,scrnheight=self.height)
        ball.create_ball()
        self.balls.append(ball)
    self.run_screensaver()
    self.win.mainloop()
  def run_screensaver(self):
    for ball in self.balls:
      ball.move_ball()
    self.canvas.after(30,self.run_screensaver)
  def exit_screensaver(self,event):
    self.win.destroy()

def main():
  Screensaver(30)#屏保上球的個數

if __name__=='__main__':
  main()