day_light.py

Go to the documentation of this file.

"""!
********************************************************************************
@file   day_light.py
@brief  get day light status for automatic theme
********************************************************************************
"""
 
import logging
from datetime import datetime, timezone, timedelta
import ephem
 
from Source.version import __title__
 
log = logging.getLogger(__title__)
 
 
def get_sun_light_time(lat: float, long: float, date: datetime, i_timezone: int) -> tuple[datetime, datetime]:
    """!
    @brief Get sun light time (rise and down time)
    @param lat : latitude of observer in degrees
    @param long : longitude of observer in degrees
    @param date : actual datetime
    @param i_timezone : timezone
    @return rise and down time of sun
    """
    observer = ephem.Observer()
    observer.lat = str(lat)
    observer.long = str(long)
    observer.date = date
 
    sun = ephem.Sun()  # pylint: disable=no-member
    delta_timezone = timedelta(hours=i_timezone)
    sunrise = observer.previous_rising(sun).datetime() + delta_timezone
    sundown = observer.previous_setting(sun).datetime() + delta_timezone
 
    return sunrise, sundown
 
 
def is_day(date: datetime, sunrise: datetime, sundown: datetime) -> bool:
    """!
    @brief Check if actual time is day (depend on rise and down time of sun)
    @param date : Latitude position
    @param sunrise : longitude position
    @param sundown : timezone
    @return day status
    """
    return sunrise.time() <= date.time() <= sundown.time()
 
 
def get_timezone() -> int:
    """!
    @brief Get timezone from time settings
    @return timezone in hours
    """
    timezone_info = datetime.now(timezone.utc).astimezone().tzinfo
    utcoffset = timezone_info.utcoffset(datetime.now()) if timezone_info else None
    if utcoffset is not None:
        i_timezone = int(utcoffset.total_seconds() / 60) // 60
    else:
        i_timezone = 0  # default timezone
    return i_timezone
 
 
def get_sun_light_status() -> bool:
    """!
    @brief Get sun light status
    @return sun light status
    @bug Sonnenzeit stimmt nur für die hinterlegten Daten. Koordinaten anhand der Zeitzone automatisch abschätzen.
    """
    date = datetime.now()
    i_timezone = get_timezone()
 
    # location for 73269 Hochdorf
    f_lat = 48.695  # Breitengrad
    f_long = 9.4615  # Längengrad
 
    sunrise, sundown = get_sun_light_time(f_lat, f_long, date, i_timezone)
    sun_light_status = is_day(date, sunrise, sundown)
 
    return sun_light_status