Refactor sun component for correctness (#7295)

* Refactor sun component for correctness

* Convert datetimes to dates for astral

* Fix tests for updated code

* Fix times now that calcs are fixed

* Move sun functions to helpers

* Fix flake on new file

* Additional tweaks from review

* Update requirements

homeassistant/helpers/sun.py

@@ -0,0 +1,87 @@
+"""Helpers for sun events."""
+import datetime
+
+from homeassistant.core import callback
+from homeassistant.util import dt as dt_util
+
+DATA_LOCATION_CACHE = 'astral_location_cache'
+
+
+@callback
+def get_astral_location(hass):
+    """Get an astral location for the current hass configuration."""
+    from astral import Location
+
+    latitude = hass.config.latitude
+    longitude = hass.config.longitude
+    timezone = hass.config.time_zone.zone
+    elevation = hass.config.elevation
+    info = ('', '', latitude, longitude, timezone, elevation)
+
+    # Cache astral locations so they aren't recreated with the same args
+    if DATA_LOCATION_CACHE not in hass.data:
+        hass.data[DATA_LOCATION_CACHE] = {}
+
+    if info not in hass.data[DATA_LOCATION_CACHE]:
+        hass.data[DATA_LOCATION_CACHE][info] = Location(info)
+
+    return hass.data[DATA_LOCATION_CACHE][info]
+
+
+@callback
+def get_astral_event_next(hass, event, utc_point_in_time=None, offset=None):
+    """Calculate the next specified solar event."""
+    import astral
+
+    location = get_astral_location(hass)
+
+    if offset is None:
+        offset = datetime.timedelta()
+
+    if utc_point_in_time is None:
+        utc_point_in_time = dt_util.utcnow()
+
+    mod = -1
+    while True:
+        try:
+            next_dt = getattr(location, event)(
+                dt_util.as_local(utc_point_in_time).date() +
+                datetime.timedelta(days=mod),
+                local=False) + offset
+            if next_dt > utc_point_in_time:
+                return next_dt
+        except astral.AstralError:
+            pass
+        mod += 1
+
+
+@callback
+def get_astral_event_date(hass, event, date=None):
+    """Calculate the astral event time for the specified date."""
+    import astral
+
+    location = get_astral_location(hass)
+
+    if date is None:
+        date = dt_util.now().date()
+
+    if isinstance(date, datetime.datetime):
+        date = dt_util.as_local(date).date()
+
+    try:
+        return getattr(location, event)(date, local=False)
+    except astral.AstralError:
+        # Event never occurs for specified date.
+        return None
+
+
+@callback
+def is_up(hass, utc_point_in_time=None):
+    """Calculate if the sun is currently up."""
+    if utc_point_in_time is None:
+        utc_point_in_time = dt_util.utcnow()
+
+    next_sunrise = get_astral_event_next(hass, 'sunrise', utc_point_in_time)
+    next_sunset = get_astral_event_next(hass, 'sunset', utc_point_in_time)
+
+    return next_sunrise > next_sunset