"""Support for Dyson Pure Cool Link Sensors."""
from libpurecool.dyson_pure_cool import DysonPureCool
from libpurecool.dyson_pure_cool_link import DysonPureCoolLink

from homeassistant.components.sensor import SensorEntity
from homeassistant.const import (
    ATTR_DEVICE_CLASS,
    ATTR_ICON,
    ATTR_UNIT_OF_MEASUREMENT,
    DEVICE_CLASS_HUMIDITY,
    DEVICE_CLASS_TEMPERATURE,
    PERCENTAGE,
    STATE_OFF,
    TEMP_CELSIUS,
    TIME_HOURS,
)

from . import DYSON_DEVICES, DysonEntity

SENSOR_ATTRIBUTES = {
    "air_quality": {ATTR_ICON: "mdi:fan"},
    "dust": {ATTR_ICON: "mdi:cloud"},
    "humidity": {
        ATTR_DEVICE_CLASS: DEVICE_CLASS_HUMIDITY,
        ATTR_UNIT_OF_MEASUREMENT: PERCENTAGE,
    },
    "temperature": {ATTR_DEVICE_CLASS: DEVICE_CLASS_TEMPERATURE},
    "filter_life": {
        ATTR_ICON: "mdi:filter-outline",
        ATTR_UNIT_OF_MEASUREMENT: TIME_HOURS,
    },
    "carbon_filter_state": {
        ATTR_ICON: "mdi:filter-outline",
        ATTR_UNIT_OF_MEASUREMENT: PERCENTAGE,
    },
    "combi_filter_state": {
        ATTR_ICON: "mdi:filter-outline",
        ATTR_UNIT_OF_MEASUREMENT: PERCENTAGE,
    },
    "hepa_filter_state": {
        ATTR_ICON: "mdi:filter-outline",
        ATTR_UNIT_OF_MEASUREMENT: PERCENTAGE,
    },
}

SENSOR_NAMES = {
    "air_quality": "AQI",
    "dust": "Dust",
    "humidity": "Humidity",
    "temperature": "Temperature",
    "filter_life": "Filter Life",
    "carbon_filter_state": "Carbon Filter Remaining Life",
    "combi_filter_state": "Combi Filter Remaining Life",
    "hepa_filter_state": "HEPA Filter Remaining Life",
}

DYSON_SENSOR_DEVICES = "dyson_sensor_devices"


def setup_platform(hass, config, add_entities, discovery_info=None):
    """Set up the Dyson Sensors."""

    if discovery_info is None:
        return

    hass.data.setdefault(DYSON_SENSOR_DEVICES, [])
    unit = hass.config.units.temperature_unit
    devices = hass.data[DYSON_SENSOR_DEVICES]

    # Get Dyson Devices from parent component
    device_ids = [device.unique_id for device in hass.data[DYSON_SENSOR_DEVICES]]
    new_entities = []
    for device in hass.data[DYSON_DEVICES]:
        if isinstance(device, DysonPureCool):
            if f"{device.serial}-temperature" not in device_ids:
                new_entities.append(DysonTemperatureSensor(device, unit))
            if f"{device.serial}-humidity" not in device_ids:
                new_entities.append(DysonHumiditySensor(device))

            # For PureCool+Humidify devices, a single filter exists, called "Combi Filter".
            # It's reported with the HEPA state, while the Carbon state is set to INValid.
            if device.state and device.state.carbon_filter_state == "INV":
                if f"{device.serial}-hepa_filter_state" not in device_ids:
                    new_entities.append(DysonHepaFilterLifeSensor(device, "combi"))
            else:
                if f"{device.serial}-hepa_filter_state" not in device_ids:
                    new_entities.append(DysonHepaFilterLifeSensor(device))
                if f"{device.serial}-carbon_filter_state" not in device_ids:
                    new_entities.append(DysonCarbonFilterLifeSensor(device))
        elif isinstance(device, DysonPureCoolLink):
            new_entities.append(DysonFilterLifeSensor(device))
            new_entities.append(DysonDustSensor(device))
            new_entities.append(DysonHumiditySensor(device))
            new_entities.append(DysonTemperatureSensor(device, unit))
            new_entities.append(DysonAirQualitySensor(device))

    if not new_entities:
        return

    devices.extend(new_entities)
    add_entities(devices)


class DysonSensor(DysonEntity, SensorEntity):
    """Representation of a generic Dyson sensor."""

    def __init__(self, device, sensor_type):
        """Create a new generic Dyson sensor."""
        super().__init__(device, None)
        self._old_value = None
        self._sensor_type = sensor_type
        self._attributes = SENSOR_ATTRIBUTES[sensor_type]

    def on_message(self, message):
        """Handle new messages which are received from the fan."""
        # Prevent refreshing if not needed
        if self._old_value is None or self._old_value != self.state:
            self._old_value = self.state
            self.schedule_update_ha_state()

    @property
    def name(self):
        """Return the name of the Dyson sensor name."""
        return f"{super().name} {SENSOR_NAMES[self._sensor_type]}"

    @property
    def unique_id(self):
        """Return the sensor's unique id."""
        return f"{self._device.serial}-{self._sensor_type}"

    @property
    def native_unit_of_measurement(self):
        """Return the unit the value is expressed in."""
        return self._attributes.get(ATTR_UNIT_OF_MEASUREMENT)

    @property
    def icon(self):
        """Return the icon for this sensor."""
        return self._attributes.get(ATTR_ICON)

    @property
    def device_class(self):
        """Return the device class of this sensor."""
        return self._attributes.get(ATTR_DEVICE_CLASS)


class DysonFilterLifeSensor(DysonSensor):
    """Representation of Dyson Filter Life sensor (in hours)."""

    def __init__(self, device):
        """Create a new Dyson Filter Life sensor."""
        super().__init__(device, "filter_life")

    @property
    def native_value(self):
        """Return filter life in hours."""
        return int(self._device.state.filter_life)


class DysonCarbonFilterLifeSensor(DysonSensor):
    """Representation of Dyson Carbon Filter Life sensor (in percent)."""

    def __init__(self, device):
        """Create a new Dyson Carbon Filter Life sensor."""
        super().__init__(device, "carbon_filter_state")

    @property
    def native_value(self):
        """Return filter life remaining in percent."""
        return int(self._device.state.carbon_filter_state)


class DysonHepaFilterLifeSensor(DysonSensor):
    """Representation of Dyson HEPA (or Combi) Filter Life sensor (in percent)."""

    def __init__(self, device, filter_type="hepa"):
        """Create a new Dyson Filter Life sensor."""
        super().__init__(device, f"{filter_type}_filter_state")

    @property
    def native_value(self):
        """Return filter life remaining in percent."""
        return int(self._device.state.hepa_filter_state)


class DysonDustSensor(DysonSensor):
    """Representation of Dyson Dust sensor (lower is better)."""

    def __init__(self, device):
        """Create a new Dyson Dust sensor."""
        super().__init__(device, "dust")

    @property
    def native_value(self):
        """Return Dust value."""
        return self._device.environmental_state.dust


class DysonHumiditySensor(DysonSensor):
    """Representation of Dyson Humidity sensor."""

    def __init__(self, device):
        """Create a new Dyson Humidity sensor."""
        super().__init__(device, "humidity")

    @property
    def native_value(self):
        """Return Humidity value."""
        if self._device.environmental_state.humidity == 0:
            return STATE_OFF
        return self._device.environmental_state.humidity


class DysonTemperatureSensor(DysonSensor):
    """Representation of Dyson Temperature sensor."""

    def __init__(self, device, unit):
        """Create a new Dyson Temperature sensor."""
        super().__init__(device, "temperature")
        self._unit = unit

    @property
    def native_value(self):
        """Return Temperature value."""
        temperature_kelvin = self._device.environmental_state.temperature
        if temperature_kelvin == 0:
            return STATE_OFF
        if self._unit == TEMP_CELSIUS:
            return float(f"{(temperature_kelvin - 273.15):.1f}")
        return float(f"{(temperature_kelvin * 9 / 5 - 459.67):.1f}")

    @property
    def native_unit_of_measurement(self):
        """Return the unit the value is expressed in."""
        return self._unit


class DysonAirQualitySensor(DysonSensor):
    """Representation of Dyson Air Quality sensor (lower is better)."""

    def __init__(self, device):
        """Create a new Dyson Air Quality sensor."""
        super().__init__(device, "air_quality")

    @property
    def native_value(self):
        """Return Air Quality value."""
        return int(self._device.environmental_state.volatil_organic_compounds)