Juice/models.py

#!/usr/bin/env python3
"""
Data models for different device types managed by the Juice IOT hub.
"""
import re
import json

import requests

class RelayDevice:
	"""
	Represents a relay receptacle device controlled by an ESP-01. The
	ESP-01 acts a simple switch to turn each receptable on or off via
	a relay. Each device only has two outputs, `OUT0` and `OUT2`.
	"""
	def __init__(self):
		self.id = ""
		self.type = "RelayDevice"
		self.description = ""
		self.location = ""
		self.ip_address = ""
		self.locked = False

		self.sub_devices = []
		self.sub_devices.append(RelayOutlet())
		self.sub_devices.append(RelayOutlet())
		self.sub_devices[0].id = 'OUT0'
		self.sub_devices[0].gpio = '0'
		self.sub_devices[1].id = 'OUT2'
		self.sub_devices[1].gpio = '2'

		self.update()

	def update(self):
		"""
		Queries the physical device and updates the internal model as
		appropriate.
		"""
		if not self.ip_address:
			return
		for sub_dev in self.sub_devices:
			res = requests.get(self.ip_address)
			gpio0 = re.search(r"GPIO0: (\bLow|\bHigh)", res.text).groups()[0]
			sub_dev.state = gpio0 == 'High'

	def toggle(self, sub_dev_id):
		"""
		Toggles the state of a sub device.
		"""
		for sub_dev in self.sub_devices:
			if sub_dev.id == sub_dev_id:
				break
		else:
			return None

		params = {sub_dev.gpio: 'toggle'}
		res = requests.get('http://' + self.ip_address + '/gpio',params=params)
		res.raise_for_status()

		state = re.search(
			rf"GPIO{sub_dev.gpio}: (\bLow|\bHigh)",
			res.text
		).groups()[0] == 'High'
		sub_dev.state = state

		return json.dumps({'ok': True, sub_dev_id: state})

	def from_dict(self, data):
		"""
		Initializes self with data from JSON dict.
		"""
		for key, value in data.items():
			setattr(self, key, value)
		self.sub_devices = []
		for sub_dev_dict in data.get('sub_devices'):
			if sub_dev_dict.get('type') == 'RelayOutlet':
				sub_dev = RelayOutlet().from_dict(sub_dev_dict)
				self.sub_devices.append(sub_dev)
			else:
				typ = sub_dev.get('type')
				raise ValueError(f"Unknown sub_device type {typ}")
		return self


class RelayOutlet:
	"""
	Represents a single outlet on a RelayDevice.
	"""
	def __init__(self):
		self.id = ""
		self.type = "RelayOutlet"
		self.description = ""
		self.gpio = ""
		self.state = False

	def from_dict(self, data):
		"""
		Initializes self with data from JSON dict.
		"""
		for key, value in data.items():
			setattr(self, key, value)
		return self


class DeviceEncoder(json.JSONEncoder):
	"""
	A custom json encoder for dumping devices to file.
	"""
	def default(self, o):
		return vars(o)


def init_network(filepath="devices.json"):
	"""
	Initializes the network of IOT devices.
	"""
	with open(filepath, 'r') as file:
		data = file.read()
	data = json.loads(data)
	network = []
	for device_dict in data:
		if device_dict.get('type') == 'RelayDevice':
			device = RelayDevice().from_dict(device_dict)
			network.append(device)
		else:
			raise ValueError(f"Unknown device type {device.get('type')}")
	return network


def save_network(network, filepath="devices.json"):
	"""
	Dumps the network to file.
	"""
	with open(filepath, 'w') as file:
		file.write(json.dumps(network, cls=DeviceEncoder, indent='\t'))