import RPi.GPIO as GPIO
from time import sleep
from datetime import datetime
from subprocess import call

def start_stop_bleep ():
	for x in range (0,3):
		GPIO.output(sounder, GPIO.HIGH)
		sleep (0.25)
		GPIO.output(sounder, GPIO.LOW)
		sleep (0.25)

sounder = 2							# GPIO number
pushbutton = 3							# GPIO number
dir = "/home/pi/"

GPIO.setmode(GPIO.BCM)
GPIO.setup(sounder, GPIO.OUT)
GPIO.setup(pushbutton, GPIO.IN, pull_up_down = GPIO.PUD_UP)

start_stop_bleep ()						# indicate powered up
while (True):
	if (GPIO.input(pushbutton) == 0): 			# Shutter release
		GPIO.output(sounder, GPIO.HIGH)			# short bleep
		sleep (0.5)
		GPIO.output(sounder, GPIO.LOW)
		filename= "img_" + datetime.now().strftime("%Y-%m-%d_%H-%M-%S") + ".jpg"
		cmd = "raspistill -o " + dir + filename
   		call (cmd, shell=True)
    		GPIO.output(sounder, GPIO.HIGH)			# long bleep
		sleep (1)
		GPIO.output(sounder, GPIO.LOW)
		if (GPIO.input(pushbutton) == 0):		# shutdown initiated
			GPIO.output(sounder, GPIO.LOW)
			sleep (0.5)
			start_stop_bleep ()			# indicate shutting down
			call ("sudo shutdown -h now", shell=True)