import enum
import time
from typing import List

from platypush.message.response.bluetooth import BluetoothScanResponse
from platypush.plugins import action
from platypush.plugins.bluetooth.ble import BluetoothBlePlugin
from platypush.plugins.switch import SwitchPlugin


class SwitchSwitchbotPlugin(SwitchPlugin, BluetoothBlePlugin):
    """
    Plugin to interact with a Switchbot (https://www.switch-bot.com/) device and
    programmatically control buttons.

    See :class:`platypush.plugins.bluetooth.ble.BluetoothBlePlugin` for how to enable BLE permissions for
    the platypush user (a simple solution may be to run it as root, but that's usually NOT a good idea).

    Requires:

        * **pybluez** (``pip install pybluez``)
        * **gattlib** (``pip install gattlib``)
        * **libboost** (on Debian ```apt-get install libboost-python-dev libboost-thread-dev``)
    """

    uuid = 'cba20002-224d-11e6-9fb8-0002a5d5c51b'
    handle = 0x16

    class Command(enum.Enum):
        """
        Base64 encoded commands
        """
        # \x57\x01\x00
        PRESS = 'VwEA'
        # # \x57\x01\x01
        ON = 'VwEB'
        # # \x57\x01\x02
        OFF = 'VwEC'

    def __init__(self, interface=None, connect_timeout=None,
                 scan_timeout=2, devices=None, **kwargs):
        """
        :param interface: Bluetooth interface to use (e.g. hci0) default: first available one
        :type interface: str

        :param connect_timeout: Timeout for the connection to the Switchbot device - default: None
        :type connect_timeout: float

        :param scan_timeout: Timeout for the scan operations
        :type scan_timeout: float

        :param devices: Devices to control, as a MAC address -> name map
        :type devices: dict
        """
        super().__init__(interface=interface, **kwargs)

        self.connect_timeout = connect_timeout if connect_timeout else 5
        self.scan_timeout = scan_timeout if scan_timeout else 2
        self.configured_devices = devices or {}
        self.configured_devices_by_name = {
            name: addr
            for addr, name in self.configured_devices.items()
        }

    def _run(self, device: str, command: Command):
        if device in self.configured_devices_by_name:
            device = self.configured_devices_by_name[device]
        n_tries = 1

        try:
            self.write(device, command.value, handle=self.handle, channel_type='random', binary=True)
        except Exception as e:
            self.logger.exception(e)
            n_tries -= 1

            if n_tries == 0:
                raise e
            time.sleep(5)

        return self.status(device)

    @action
    def press(self, device):
        """
        Send a press button command to a device

        :param device: Device name or address
        :type device: str
        """
        return self._run(device, self.Command.PRESS)

    @action
    def toggle(self, device, **kwargs):
        return self.press(device)

    @action
    def on(self, device, **kwargs):
        """
        Send a press-on button command to a device

        :param device: Device name or address
        :type device: str
        """
        return self._run(device, self.Command.ON)

    @action
    def off(self, device, **kwargs):
        """
        Send a press-off button command to a device

        :param device: Device name or address
        :type device: str
        """
        return self._run(device, self.Command.OFF)

    @action
    def scan(self, interface: str = None, duration: int = 10) -> BluetoothScanResponse:
        """
        Scan for available Switchbot devices nearby.

        :param interface: Bluetooth interface to scan (default: default configured interface)
        :param duration: Scan duration in seconds
        """

        devices = super().scan(interface=interface, duration=duration).devices
        compatible_devices = {}

        for dev in devices:
            try:
                characteristics = [
                    chrc for chrc in self.discover_characteristics(
                        dev['addr'], channel_type='random', wait=False,
                        timeout=self.scan_timeout).characteristics
                    if chrc.get('uuid') == self.uuid
                ]

                if characteristics:
                    compatible_devices[dev['addr']] = None
            except Exception as e:
                self.logger.warning('Device scan error', e)

        return BluetoothScanResponse(devices=compatible_devices)

    @property
    def switches(self) -> List[dict]:
        return [
            {
                'address': addr,
                'id': addr,
                'name': name,
                'on': False,
            }
            for addr, name in self.configured_devices.items()
        ]


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