import pywemo

# Total number of wemo devices inside the broadcast domain
NUM_WEMO_DEVICES = 12

# Context: dumb_switch is just a button that looks like a light switch.
#          It is always powered on but does not actually sit in the flow of the circuit.
#          We use this "button" switch to be the 2nd location of the three way switch.
#          If either side is pressed (toggled) the other side should match BinaryState.
#          This allows for the dumb button switch to control the other side of the pair.
#          real_switch is the actual switch that should be controlled (the other side of the pair)
#
# Prereqs: You need to know the MAC addresses of both sides of the three-way switch.
#          See discove_all.py for help with doing this part.
#          This seemed to be the simplist way to setup the switch without doing anything crazy
#          like editing the name of the switch and searching for some spcific name 
#          (I thought about doing this)


class ThreeWaySwitch:
    def __init__(self, regsub, name, dumb_switch_mac, real_switch_mac):
        self.name = name
        self.real_switch = None  # set during discovery
        self.real_switch_mac = real_switch_mac
        self.dumb_switch = None  # set during discovery
        self.dumb_switch_mac = dumb_switch_mac
        self.regsub = regsub  # pywemo RegistrySubscription() type

    def discover(self):
        while self.real_switch == None or self.dumb_switch == None:
            print('Searching for "{}" devices ... '.format(self.name), end="")
            devices = pywemo.discover_devices()
            print("saw {}/{} devices.".format(len(devices), NUM_WEMO_DEVICES))
            for d in devices:
                if d.mac == self.real_switch_mac:
                    self.real_switch = d
                if d.mac == self.dumb_switch_mac:
                    self.dumb_switch = d
        print(
            "  real_switch:  {:24}{:24}{:12}".format(
                self.real_switch.name, self.real_switch.host, self.real_switch.mac
            )
        )
        print(
            "  dumb_switch:  {:24}{:24}{:12}".format(
                self.dumb_switch.name, self.dumb_switch.host, self.dumb_switch.mac
            )
        )

    def sync(self):
        self.real_switch.set_state(0)
        self.dumb_switch.set_state(0)

    def register_callbacks(self):
        self.regsub.register(self.real_switch)
        self.regsub.register(self.dumb_switch)
        self.regsub.on(self.real_switch, "BinaryState", self.toggle_callback)
        self.regsub.on(self.dumb_switch, "BinaryState", self.toggle_callback)
        print('"{}" devices callback registration complete\n'.format(self.name))

    def toggle_callback(self, device, cb_type, value):
        print("  {:16}{:24}{:24}{:12}".format(self.name, device.name, cb_type, value))
        if device.mac == self.real_switch.mac:
            self.dumb_switch.set_state(value)
        if device.mac == self.dumb_switch.mac:
            self.real_switch.set_state(value)


if __name__ == "__main__":
    regsub = pywemo.SubscriptionRegistry()

    # three way switches: (Name, dummy switch MAC, real_switch switch MAC)
    kitchen = ThreeWaySwitch(regsub, "Kitchen Dimmer", "24F5A25D64CC", "58EF68BB617A")
    foyer = ThreeWaySwitch(regsub, "Foyer Dimmer", "94103E4E72A0", "58EF68BB756C")
    all_3ways = [kitchen, foyer]

    print("--- Starting discovery of {} three-way circuits ---".format(len(all_3ways)))
    for tw in all_3ways:
        tw.discover()
        tw.sync()
        tw.register_callbacks()

    print("--- Starting callback handler loop ---")
    regsub.start()