import RPi.GPIO as GPIO
import time, logging, enum
from threading import Lock
from functools import partial
from collections import namedtuple
from enum import Enum, auto

from auxilary import CountdownTimer, resetUSBDevice
from config import stateFile
from sensors import startDoorSensor, startMotionSensor
from gmail import intruderAlert
from listeners import KeypadListener, PipeListener
from blinkenLights import Blinkenlights
from soundLib import SoundLib
from webInterface import startWebInterface
from stream import Camera, FileDump

logger = logging.getLogger(__name__)

class SIGNALS(enum.Enum):
	ARM = enum.auto()
	INSTANT_ARM = enum.auto()
	DISARM = enum.auto()
	TIMOUT = enum.auto()
	TRIGGER = enum.auto()

class State:
	def __init__(self, stateMachine, name, entryCallbacks=[], exitCallbacks=[], sound=None):
		self.stateMachine = stateMachine
		self.name = name
		self.entryCallbacks = entryCallbacks
		self.exitCallbacks = exitCallbacks
		
		sfx = stateMachine.soundLib.soundEffects
		
		self._sound = sfx[name] if not sound and name in sfx else sound
		
	def entry(self):
		logger.info('entering ' + self.name)
		if self._sound:
			self._sound.play()
		for c in self.entryCallbacks:
			c()
		
	def exit(self):
		logger.info('exiting ' + self.name)
		if self._sound:
			self._sound.stop()
		for c in self.exitCallbacks:
			c()

	def next(self, signal):
		if signal in SIGNALS:
			s = (self, signal)
			t = self.stateMachine.transitionTable
			return self if s not in t else t[s]
		else:
			raise Exception('Illegal signal')
	
	def __str__(self):
		return self.name
	
	def __eq__(self, other):
		return self.name == other
		
	def __hash__(self):
		return hash(self.name)

class StateMachine:
	def __init__(self):
		self._lock = Lock()
		
		self.soundLib = SoundLib()
		self.LED = Blinkenlights(17)
		self.camera = Camera()
		self.fileDump = FileDump()
		
		secretTable = {
			"dynamoHum": 	partial(self.selectState, SIGNALS.DISARM),
			"zombyWoof": 	partial(self.selectState, SIGNALS.ARM),
			"imTheSlime": 	partial(self.selectState, SIGNALS.INSTANT_ARM)
		}
		
		def secretCallback(secret, logger):
			if secret in secretTable:
				secretTable[secret]()
				logger.debug('Secret pipe listener received: \"%s\"', secret)
			elif logger:
				logger.debug('Secret pipe listener received invalid secret')
	
		self.secretListener = PipeListener(
			callback = secretCallback,
			name = 'secret'
		)

		self.keypadListener = KeypadListener(
			stateMachine = self,
			callbackDisarm = partial(self.selectState, SIGNALS.DISARM),
			callbackArm = partial(self.selectState, SIGNALS.ARM),
			soundLib = self.soundLib,
			passwd = '5918462'
		)
		
		def startTimer(t, sound):
			self._timer = CountdownTimer(t, partial(self.selectState, SIGNALS.TIMOUT), sound)
			
		def stopTimer():
			if self._timer.is_alive():
				self._timer.stop()
				self._timer = None

		blinkingLED = partial(self.LED.setBlink, True)
		sfx = self.soundLib.soundEffects

		stateObjs = [
			State(
				self,
				name = 'disarmed',
				entryCallbacks = [partial(self.LED.setBlink, False)]
			),
			State(
				self,
				name = 'disarmedCountdown',
				entryCallbacks = [blinkingLED, partial(startTimer, 30, sfx['disarmedCountdown'])],
				exitCallbacks = [stopTimer]
			),
			State(
				self,
				name = 'armed',
				entryCallbacks = [blinkingLED]
			),
			State(
				self,
				name = 'armedCountdown',
				entryCallbacks = [blinkingLED, partial(startTimer, 30, sfx['armedCountdown'])],
				exitCallbacks = [stopTimer]
			),
			State(
				self,
				name = 'triggered',
				entryCallbacks = [blinkingLED, intruderAlert]
			)
		]
		
		for s in stateObjs:
			s.entryCallbacks.append(self.keypadListener.resetBuffer)
		
		self.states = namedtuple('States', [s.name for s in stateObjs])(*stateObjs)

		self.currentState = getattr(self.states, stateFile['state'])
		
		self.transitionTable = {
			(self.states.disarmed, 			SIGNALS.ARM): 			self.states.disarmedCountdown,
			(self.states.disarmed, 			SIGNALS.INSTANT_ARM): 	self.states.armed,
			
			(self.states.disarmedCountdown,	SIGNALS.DISARM): 		self.states.disarmed,
			(self.states.disarmedCountdown, SIGNALS.TIMOUT):		self.states.armed,
			(self.states.disarmedCountdown, SIGNALS.INSTANT_ARM):	self.states.armed,
			
			(self.states.armed, 			SIGNALS.DISARM): 		self.states.disarmed,
			(self.states.armed, 			SIGNALS.TRIGGER): 		self.states.armedCountdown,
			
			(self.states.armedCountdown, 	SIGNALS.DISARM): 		self.states.disarmed,
			(self.states.armedCountdown, 	SIGNALS.ARM): 			self.states.armed,
			(self.states.armedCountdown, 	SIGNALS.TIMOUT):		self.states.triggered,
			
			(self.states.triggered, 		SIGNALS.DISARM):		self.states.disarmed,
			(self.states.triggered, 		SIGNALS.ARM):			self.states.armed,
		}
		
	def start(self):
		resetUSBDevice('1-1', logger)
		
		self.soundLib.start()
		self.LED.start()
		self.keypadListener.start()
		self.secretListener.start()
		self.camera.start()
		self.fileDump.start()
		
		def action():
			if self.currentState == self.states.armed:
				self.selectState(SIGNALS.TRIGGER)
		
		sensitiveStates = (self.states.armed, self.states.armedCountdown, self.states.triggered)

		def actionVideo(pin):
			if self.currentState in sensitiveStates:
				self.selectState(SIGNALS.TRIGGER)
				self.fileDump.addInitiator(pin)
				while GPIO.input(pin) and self.currentState in sensitiveStates:
					time.sleep(0.1)
				self.fileDump.removeInitiator(pin)

		startMotionSensor(5, 'Nate\'s room', action)
		startMotionSensor(19, 'front door', action)
		startMotionSensor(26, 'Laura\'s room', action)
		startMotionSensor(6, 'deck window', partial(actionVideo, 6))
		startMotionSensor(13, 'kitchen bar', partial(actionVideo, 13))
		
		startDoorSensor(22, action, self.soundLib.soundEffects['door'])
		
		startWebInterface(self)
		
		self.currentState.entry()
		
	def selectState(self, signal):
		with self._lock:
			nextState = self.currentState.next(signal)
			if nextState != self.currentState:
				self.currentState.exit()
				self.currentState = nextState
				self.currentState.entry()
			
			stateFile['state'] = self.currentState.name
			
			logger.info('state changed to %s', self.currentState)
		
	def __del__(self):
		for i in ['LED', 'camera', 'fileDump', 'soundLib', 'secretListener', 'keypadListener']:
			try:
				getattr(self, i).__del__()
			except AttributeError:
				pass