import asyncio
from tasks import ATask
from ws.message import MsgIo
from utils.value import ChangedFloat
from components import APid, AStirrer
from components.sud import Sud, SudState

# How close theta_ist needs to be to theta_soll_set to count as "reached".
TEMP_REACHED_TOLERANCE = 0.2


class SudTask(ATask):
	def __init__(self, sud: Sud, tc: APid, stirrer: AStirrer, interval, msg_handler: MsgIo):
		ATask.__init__(self, interval)
		self.sud = sud
		self.tc = tc
		self.stirrer = stirrer
		self.msg_handler = msg_handler
		msg_handler.set_recv_handler(self.recv)

	def apply_stirrer(self, step):
		speed = step.get('stirrer_speed', 0)
		on = step.get('stirrer_time_on', 0)
		off = step.get('stirrer_time_off', 0)
		cycle = on + off
		if cycle > 0:
			duty = on / cycle
		else:
			cycle = 1.0
			duty = 1.0 if speed > 0 else 0.0

		self.stirrer.set_cycle_time(cycle)
		self.stirrer.set_duty_cycle(duty)
		self.stirrer.set_speed(speed)

	def on_step_changed(self, step):
		if step is not None:
			if step['type'] == 'heat':
				self.tc.set_theta_soll(step['temp'])
				self.tc.set_heatrate_soll(step['rate'])
			self.apply_stirrer(step)

		asyncio.create_task(self.send({'Step': {
			'Index': self.sud.index,
			'Type': step['type'] if step else None,
			'Descr': step.get('descr') if step else None,
			'Temp': step.get('temp') if step else None,
			'Rate': step.get('rate') if step else None,
			'Duration': step.get('duration') if step else None,
			'WaitForUser': step.get('user_wait_for_continue', False) if step else None,
		}}))

	def on_state_changed(self, value):
		asyncio.create_task(self.send({'State': str(value)}))

		if value == SudState.DONE:
			self.stirrer.set_duty_cycle(1.0)
			self.stirrer.set_speed(0)

	def on_user_message_changed(self, value):
		asyncio.create_task(self.send({'UserMessage': value}))

	def on_hold_remaining_changed(self, value):
		asyncio.create_task(self.send({'HoldRemaining': value}))

	async def recv(self, data):
		for pair in data.items():
			if 'Start' in pair[0]:
				self.sud.start()
			elif 'Confirm' in pair[0]:
				self.sud.confirm()

	async def send(self, data):
		await self.msg_handler.send(data)

	async def on_process(self):
		print("{}: Started with interval {} s".format(self.msg_handler.get_key(), self.interval))

		self.sud.set_on_changed('step', self.on_step_changed)
		self.sud.set_on_changed('state', self.on_state_changed)
		self.sud.set_on_changed('user_message', self.on_user_message_changed)
		self.sud.set_on_changed('hold_remaining', ChangedFloat(self.on_hold_remaining_changed, prec=0).set)

		asyncio.create_task(self.send({'Name': self.sud.name, 'Description': self.sud.description}))

		while True:
			if self.sud.state == SudState.RAMPING:
				# Compare against the controller's own live setpoint/measurement
				# rather than its state machine, which can still read HOLD from
				# the previous step for one tick after a new target is pushed.
				if abs(self.tc.get_theta_ist() - self.tc.get_theta_soll_set()) < TEMP_REACHED_TOLERANCE:
					self.sud.temp_reached()
			self.sud.tick(self.interval)
			await asyncio.sleep(self.interval)