#!/usr/bin/env python3
from typing import Optional
from argparse import ArgumentParser, ArgumentError

from home.config import config
from home.mqtt import MqttNode, get_mqtt_modules, import_mqtt_module, MqttModule

mqtt: Optional[MqttNode] = None


def add_module(module: str) -> MqttModule:
    module = import_mqtt_module(module)
    if not hasattr(module, 'MODULE_NAME'):
        raise RuntimeError(f'MODULE_NAME not found in module {m}')
    cl = getattr(module, getattr(module, 'MODULE_NAME'))
    instance = cl()
    mqtt.add_module(instance)
    return instance


if __name__ == '__main__':
    parser = ArgumentParser()
    parser.add_argument('--node-id', type=str, required=True)
    parser.add_argument('--modules', type=str, choices=get_mqtt_modules(), nargs='*',
                        help='mqtt modules to include')
    parser.add_argument('--switch-relay', choices=[0, 1], type=int,
                        help='send relay state')
    parser.add_argument('--switch-relay-secret', type=str,
                        help='secret password to switch relay')

    config.load('mqtt_util', parser=parser)
    arg = parser.parse_args()

    if (arg.switch_relay is not None or arg.switch_relay_secret is not None) and 'relay' not in arg.modules:
        raise ArgumentError(None, '--relay is only allowed when \'relay\' module included in --modules')

    if (arg.switch_relay is not None and arg.switch_relay_secret is None) or (arg.switch_relay is None and arg.switch_relay_secret is not None):
        raise ArgumentError(None, 'both --switch-relay and --switch-relay-secret are required')

    mqtt = MqttNode(node_id=arg.node_id)

    # must-have modules
    add_module('ota')
    add_module('diagnostics')

    if arg.modules:
        for m in arg.modules:
            module_instance = add_module(m)
            if m == 'relay' and arg.switch_relay is not None:
                module_instance.switchpower(mqtt,
                                            arg.switch_relay == 1,
                                            arg.switch_relay_secret)

    mqtt.configure_tls()
    try:
        mqtt.connect_and_loop()
    except KeyboardInterrupt:
        mqtt.disconnect()