"""Support for the Mikrotik Router sensor service."""

import logging
from homeassistant.core import callback
from homeassistant.helpers.dispatcher import async_dispatcher_connect
from homeassistant.helpers.entity import Entity
from homeassistant.const import (
    CONF_NAME,
    ATTR_ATTRIBUTION,
    ATTR_DEVICE_CLASS,
)

from .const import (
    DOMAIN,
    DATA_CLIENT,
    ATTRIBUTION,
)

_LOGGER = logging.getLogger(__name__)

ATTR_ICON = "icon"
ATTR_LABEL = "label"
ATTR_UNIT = "unit"
ATTR_GROUP = "group"
ATTR_PATH = "data_path"
ATTR_ATTR = "data_attr"

SENSOR_TYPES = {
    'system_cpu-load': {
        ATTR_DEVICE_CLASS: None,
        ATTR_ICON: "mdi:speedometer",
        ATTR_LABEL: 'CPU load',
        ATTR_UNIT: "%",
        ATTR_GROUP: "System",
        ATTR_PATH: "resource",
        ATTR_ATTR: "cpu-load",
    },
    'system_memory-usage': {
        ATTR_DEVICE_CLASS: None,
        ATTR_ICON: "mdi:memory",
        ATTR_LABEL: 'Memory usage',
        ATTR_UNIT: "%",
        ATTR_GROUP: "System",
        ATTR_PATH: "resource",
        ATTR_ATTR: "memory-usage",
    },
    'system_hdd-usage': {
        ATTR_DEVICE_CLASS: None,
        ATTR_ICON: "mdi:harddisk",
        ATTR_LABEL: 'HDD usage',
        ATTR_UNIT: "%",
        ATTR_GROUP: "System",
        ATTR_PATH: "resource",
        ATTR_ATTR: "hdd-usage",
    },
}


# ---------------------------
#   async_setup_entry
# ---------------------------
async def async_setup_entry(hass, config_entry, async_add_entities):
    """Set up device tracker for Mikrotik Router component."""
    inst = config_entry.data[CONF_NAME]
    mikrotik_controller = hass.data[DOMAIN][DATA_CLIENT][config_entry.entry_id]
    sensors = {}

    @callback
    def update_controller():
        """Update the values of the controller."""
        update_items(inst, mikrotik_controller, async_add_entities, sensors)

    mikrotik_controller.listeners.append(
        async_dispatcher_connect(hass, mikrotik_controller.signal_update, update_controller)
    )

    update_controller()
    return


# ---------------------------
#   update_items
# ---------------------------
@callback
def update_items(inst, mikrotik_controller, async_add_entities, sensors):
    """Update sensor state from the controller."""
    new_sensors = []

    for sensor in SENSOR_TYPES:
        item_id = "{}-{}".format(inst, sensor)
        if item_id in sensors:
            if sensors[item_id].enabled:
                sensors[item_id].async_schedule_update_ha_state()
            continue

        sensors[item_id] = MikrotikControllerSensor(mikrotik_controller=mikrotik_controller, inst=inst, sensor=sensor)
        new_sensors.append(sensors[item_id])

    if new_sensors:
        async_add_entities(new_sensors, True)

    return


# ---------------------------
#   MikrotikControllerSensor
# ---------------------------
class MikrotikControllerSensor(Entity):
    """Define an Mikrotik Controller sensor."""

    def __init__(self, mikrotik_controller, inst, sensor):
        """Initialize."""
        self._inst = inst
        self._sensor = sensor
        self._ctrl = mikrotik_controller
        self._data = mikrotik_controller.data[SENSOR_TYPES[sensor][ATTR_PATH]]
        self._type = SENSOR_TYPES[sensor]
        self._attr = SENSOR_TYPES[sensor][ATTR_ATTR]

        self._device_class = None
        self._state = None
        self._icon = None
        self._unit_of_measurement = None
        self._attrs = {ATTR_ATTRIBUTION: ATTRIBUTION}

    @property
    def name(self):
        """Return the name."""
        return "{} {}".format(self._inst, self._type[ATTR_LABEL])

    @property
    def state(self):
        """Return the state."""
        val = "unknown"
        if self._attr in self._data:
            val = self._data[self._attr]

        return val

    @property
    def device_state_attributes(self):
        """Return the state attributes."""
        return self._attrs

    @property
    def icon(self):
        """Return the icon."""
        self._icon = self._type[ATTR_ICON]
        return self._icon

    @property
    def device_class(self):
        """Return the device_class."""
        return self._type[ATTR_DEVICE_CLASS]

    @property
    def unique_id(self):
        """Return a unique_id for this entity."""
        return "{}-{}".format(self._inst.lower(), self._sensor.lower())

    @property
    def unit_of_measurement(self):
        """Return the unit the value is expressed in."""
        return self._type[ATTR_UNIT]

    @property
    def available(self):
        """Return True if entity is available."""
        return bool(self._ctrl.data)

    @property
    def device_info(self):
        """Return a port description for device registry."""
        info = {
            "identifiers": {(DOMAIN, "serial-number", self._ctrl.data['routerboard']['serial-number'], "switch", "PORT")},
            "manufacturer": self._ctrl.data['resource']['platform'],
            "model": self._ctrl.data['resource']['board-name'],
            "name": self._type[ATTR_GROUP],
        }
        return info

    async def async_update(self):
        """Synchronize state with controller."""
        return

    async def async_added_to_hass(self):
        """Port entity created."""
        _LOGGER.debug("New sensor %s (%s)", self._inst, self._sensor)
        return