External ESPHome component

device/device.yaml registers an external_components source pointing at this repository:

external_components:
  - source:
      type: git
      url: https://github.com/jtenniswood/espcontrol
      ref: main
      path: components
    components: [espcontrol]
    refresh: 0s

espcontrol:

Python layer

components/espcontrol/__init__.py currently defines an empty CONFIG_SCHEMA and to_code — the package is present so ESPHome accepts the espcontrol: key and can link C++ headers.

C++ / headers

components/espcontrol/sun_calc.h provides:

• TzCoord table — representative lat/lon for each IANA timezone option matching Clock: Timezone in addon/time.yaml
• lookup_tz_coords — resolve coordinates for a timezone id string
• calc_sunrise_sunset — astronomical sunrise/sunset for a calendar date and position (used by addon/backlight_schedule.yaml lambdas)

This keeps sunrise/sunset and day/night brightness on-device without calling external APIs.

Related

• Backlight schedule — how computed times drive brightness