import threading
import RPi.GPIO as g

INHIBIT_PIN=40
MONEY_PIN=38
AMOUNT_PER_PULSE=5
TIMEOUT = 30

g.setmode(g.BOARD)

g.setup(INHIBIT_PIN, g.OUT)
g.output(INHIBIT_PIN, True)

g.setup(MONEY_PIN, g.IN, pull_up_down = g.PUD_UP)


class MoneyTransaction:
	def __init__(self, end_callback, add_money_callback) -> None:
		self.end_callback = end_callback
		self.add_money_callback = add_money_callback
		self.lock = threading.Lock()
		self.lock.acquire_lock(blocking=True)
		self.timer = None
		self.timer_lock = threading.Lock()
	
	def __end_callback(self, _ = None):
		print("End Callback")
		self.end_callback()
		g.output(INHIBIT_PIN, True) # Disable Bill Acceptor
		try:
			g.remove_event_detect(MONEY_PIN)
		except Exception:
			pass
		with self.timer_lock:
			if self.timer is not None:
				self.timer.cancel()
			self.timer = None
		self.lock.release_lock()
		
	def __add_money_callback(self, _ = None):
		with self.timer_lock:
			if self.timer is not None:
				self.timer.cancel()
			self.timer = threading.Timer(TIMEOUT, self.__end_callback) # create Timeout
			self.timer.start()
		self.add_money_callback(AMOUNT_PER_PULSE)
	
	def start(self):
		print("Start Transaction")
		g.output(INHIBIT_PIN, False) # Enable Bill Acceptor
		with self.timer_lock:
			self.timer = threading.Timer(TIMEOUT, self.__end_callback) # create Timeout
			self.timer.start()
		g.add_event_detect(MONEY_PIN, g.FALLING, callback = self.__add_money_callback, bouncetime=130)
	def stop(self):
		self.__end_callback()