core/homeassistant/components/environment_canada/camera.py

"""
Support for the Environment Canada radar imagery.

For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/camera.environment_canada/
"""
import datetime
import logging

from env_canada import ECRadar
import voluptuous as vol

from homeassistant.components.camera import PLATFORM_SCHEMA, Camera
from homeassistant.const import (
    ATTR_ATTRIBUTION,
    CONF_LATITUDE,
    CONF_LONGITUDE,
    CONF_NAME,
)
import homeassistant.helpers.config_validation as cv
from homeassistant.util import Throttle

_LOGGER = logging.getLogger(__name__)

ATTR_STATION = "station"
ATTR_LOCATION = "location"
ATTR_UPDATED = "updated"

CONF_ATTRIBUTION = "Data provided by Environment Canada"
CONF_STATION = "station"
CONF_LOOP = "loop"
CONF_PRECIP_TYPE = "precip_type"

MIN_TIME_BETWEEN_UPDATES = datetime.timedelta(minutes=10)

PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
    {
        vol.Optional(CONF_LOOP, default=True): cv.boolean,
        vol.Optional(CONF_NAME): cv.string,
        vol.Optional(CONF_STATION): cv.matches_regex(r"^C[A-Z]{4}$|^[A-Z]{3}$"),
        vol.Inclusive(CONF_LATITUDE, "latlon"): cv.latitude,
        vol.Inclusive(CONF_LONGITUDE, "latlon"): cv.longitude,
        vol.Optional(CONF_PRECIP_TYPE): ["RAIN", "SNOW"],
    }
)


def setup_platform(hass, config, add_devices, discovery_info=None):
    """Set up the Environment Canada camera."""

    if config.get(CONF_STATION):
        radar_object = ECRadar(
            station_id=config[CONF_STATION], precip_type=config.get(CONF_PRECIP_TYPE)
        )
    else:
        lat = config.get(CONF_LATITUDE, hass.config.latitude)
        lon = config.get(CONF_LONGITUDE, hass.config.longitude)
        radar_object = ECRadar(coordinates=(lat, lon))

    add_devices([ECCamera(radar_object, config.get(CONF_NAME))], True)


class ECCamera(Camera):
    """Implementation of an Environment Canada radar camera."""

    def __init__(self, radar_object, camera_name):
        """Initialize the camera."""
        super().__init__()

        self.radar_object = radar_object
        self.camera_name = camera_name
        self.content_type = "image/gif"
        self.image = None
        self.timestamp = None

    def camera_image(self):
        """Return bytes of camera image."""
        self.update()
        return self.image

    @property
    def name(self):
        """Return the name of the camera."""
        if self.camera_name is not None:
            return self.camera_name
        return " ".join([self.radar_object.station_name, "Radar"])

    @property
    def device_state_attributes(self):
        """Return the state attributes of the device."""
        attr = {
            ATTR_ATTRIBUTION: CONF_ATTRIBUTION,
            ATTR_LOCATION: self.radar_object.station_name,
            ATTR_STATION: self.radar_object.station_code,
            ATTR_UPDATED: self.timestamp,
        }

        return attr

    @Throttle(MIN_TIME_BETWEEN_UPDATES)
    def update(self):
        """Update radar image."""
        if CONF_LOOP:
            self.image = self.radar_object.get_loop()
        else:
            self.image = self.radar_object.get_latest_frame()
        self.timestamp = self.radar_object.timestamp.isoformat()