# | P1-17 | P1-18 | P1-21 | P1-19 | P1-23 | P1-24 | P1-25  |
# -________________________________________________________-
#                     Raspberry Pi

import spidev
import time
import threading
import collections

class dummy_context_mgr():
	def __enter__(self):
		return None
	def __exit__(self, exc_type, exc_value, traceback):
		return False

		spi = spidev.SpiDev()
		spi.open(spi_bus, spi_dev)
		self._spi = spi

		self._dequeue_thread = None
		self._last_syncword = None

		self._software_tx_queue = {}
		self._software_tx_queue_next_time = {}

		self.configure(config, update = False)

		if len(self._register_map) != 53:
			raise ValueError('Inconsistent register map!')



		return None

	def __del__(self):
		self._debug('Deleting object')
		self._config['use_software_tx_queue'] = False
		self._spi.close()

	def _debug(self, message):
		if 'debug_log_command' in self._config:
			self._config['debug_log_command'](message)
		return None

	def _error(self, message):
		log_command = None
		if 'error_log_command' in self._config:
			log_command = self._config['error_log_command']
		elif 'debug_log_command' in self._config:
			log_command = self._config['debug_log_command']
		log_command(message)
		return None

	def _get_mutex(self, real_mutex = True):
		if not real_mutex:
			return dummy_context_mgr()

		mutex = self._config.get('mutex', dummy_context_mgr())
		return mutex

		if include_length:
			new_message = new_message + [len(message)]
		new_message = new_message + message
		log_message = [] + new_message

		# Transfer the message
		with self._get_mutex(lock):
			result = self._spi.xfer(new_message, self._spi.max_speed_hz, 0)

		self._debug("Writing: {} = {}".format(log_message, result))

		return new_message

	def transmit(self, message, channel = None, lock = True, post_delay = 0, syncword = None, submit_queue = '__DEFAULT__'):
		# If we are using a radio transmit queue, just queue this message

				if radio_status['framer_status'] == 0:
					sent_packet = False
					break
				time.sleep(0.001)

		if post_delay != 0:

			time.sleep(post_delay)

		return sent_packet

	def multi_transmit(self, message, channels, retries = 3, delay = 0.1, syncword = None, submit_queue = '__DEFAULT__'):
		if len(channels) == 0 or retries == 0:
			self._error("Asked to send the message {} a total of zero times ({} channels, {} retries)".format(message, channels, retries))

		for channel_idx in range(len(channels)):
			if channel_idx == (len(channels) - 1):
				retries -= 1
			channel = channels[channel_idx]
			for i in range(retries):
				if not self.transmit(message, channel, post_delay = 0, syncword = syncword, submit_queue = submit_queue):
					return False
		if not self.transmit(message, channel, post_delay = delay, syncword = syncword, submit_queue = submit_queue):
			return False

		return True

	def _enqueue(self, submit_queue, syncword, message, channel, post_delay = 0):
		if not self._should_use_queue():
			raise ValueError('internal error: _enqueue called with queueing disabled')

		with self._software_tx_queue_mutex:
			if submit_queue not in self._software_tx_queue:
				self._software_tx_queue[submit_queue] = collections.deque([])







			self._software_tx_queue[submit_queue].append({
				'syncword': syncword,
				'message': message,
				'channel': channel,

				'post_delay': post_delay
			})

		return None

	def _run_queue(self):
		self._debug("Started run_queue process")

		sleep_time = 0
		while True:
			if sleep_time != 0:
				self._debug("Sleeping for {} seconds".format(sleep_time))
				time.sleep(sleep_time)

			with self._software_tx_queue_mutex:
				for queue in self._software_tx_queue:
					if len(self._software_tx_queue[queue]) != 0:
						self._debug("Running the queue named {}: {} items left".format(queue, len(self._software_tx_queue[queue])))

			try:
				[processed_items, remaining_items] = self._run_queue_once()
			except Exception as error_info:
				self._error("Failed to run queue: {}".format(error_info.args))
				processed_items = 0
				remaining_items = 0

			self._debug("Completed running the queue, did {} items and {} items left (continue queue = {})".format(processed_items, remaining_items, self._should_use_queue()))

			if remaining_items == 0:
				# If the queue is empty and we are no longer queuing
				# events, exit this function (which should be joined)
				if not self._should_use_queue():
					self._debug("Request to stop run_queue process, exiting")
					return None

				# If there are no events, wait a bit
				# longer before trying again
				sleep_time = 0.5
				continue

			if processed_items == 0:
				# If we processed no items, but there are items left to
				# process, back off slightly
				if sleep_time == 0:
					sleep_time = 0.001
				else:
					sleep_time = min(0.5, sleep_time * 2)
				continue

			# If there are more events to process, try again
			sleep_time = 0

		return None

	def _run_queue_once(self):

		to_transmit = []
		remaining_items = 0
		now = time.time()
		with self._software_tx_queue_mutex:
			for submit_queue in self._software_tx_queue:
				# Determine if we should run this queue yet
				if submit_queue not in self._software_tx_queue_next_time:
					self._software_tx_queue_next_time[submit_queue] = now

				queue_next_time = self._software_tx_queue_next_time[submit_queue]
				if now < queue_next_time:
					remaining_items += len(self._software_tx_queue[submit_queue])

					continue

				# Record how many items to pop off this queue
				pop_items = 0
				for item in self._software_tx_queue[submit_queue]:
					pop_items += 1

					# If the last item we're about to transmit requires a delay, make
					# a note of it in the queue time and don't pull anything else
					# from this queue
					self._software_tx_queue_next_time[submit_queue] = now + item['post_delay']
					if item['post_delay'] != 0:
						break

				# Pop off the items to transmit in this run into a list
				if pop_items != 0:
					self._debug("Found {} items to transmit in the {} queue".format(pop_items, submit_queue))
				while pop_items != 0:
					to_transmit.append(self._software_tx_queue[submit_queue].popleft())
					pop_items -= 1

				remaining_items += len(self._software_tx_queue[submit_queue])

		default_syncword = None

		self._debug("Getting ready to transmit {} items".format(len(to_transmit)))
		with self._get_mutex():
			for item in to_transmit:
				self._debug("Transmitting item {}".format(item))
				syncword = item['syncword']
				message = item['message']
				channel = item['channel']

				if syncword is not None:
					default_syncword = syncword
				else:
					syncword = default_syncword

				if message is None or channel is None:
					continue


				self.transmit(message, channel, lock = False, submit_queue = None, syncword = syncword, post_delay = 0)


		return [len(to_transmit), remaining_items]
		
	def start_listening(self, channel):
		# Initialize the receiver
		self.stop_listening()

		# Go into listening mode
		self.put_register_bits('radio_state', {