diff options
| -rw-r--r-- | colortemp.go | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/colortemp.go b/colortemp.go index 051ca54..a708a0b 100644 --- a/colortemp.go +++ b/colortemp.go @@ -1,16 +1,36 @@ package main import ( + "log" "math" "time" hue "github.com/benburwell/gohue" + "github.com/cpucycle/astrotime" ) type ColorTemperature uint -func getDesiredColorTemperature(at time.Time) ColorTemperature { - return 1800 +const LATITUDE = 42.348333 +const LONGITUDE = 71.1675 + +// Get the correct color temperature for a given time. If the time is between +// sunrise and sunset, a high CT is selected. Otherise, during night, a low +// color temperature is used. +// +// TODO: This is a naive approach and should be revisited +func getDesiredColorTemperature(t time.Time) ColorTemperature { + log.Printf("Calculating sunrise/sunset for: %s\n", t.Format(time.RFC3339)) + sunrise := astrotime.CalcSunrise(t, LATITUDE, LONGITUDE) + sunset := astrotime.CalcSunset(t, LATITUDE, LONGITUDE) + log.Printf("Sunrise: %s, Sunset: %s\n", sunrise.Format(time.RFC3339), sunset.Format(time.RFC3339)) + if t.After(sunrise) && t.Before(sunset) { + log.Println("Daytime, setting high CT") + return 6500 + } else { + log.Println("Nighttime, setting low CT") + return 1800 + } } // Translate a desired color temperature in Kelvins to a value comprehensible |