{ config, lib, ... }:
let
  holiday-range = month: dayA: dayB:
    map (day: "${month}-${toString day}")
      (map (lib.fixedWidthNumber 2) (lib.range dayA dayB));
  privateHolidays = import <secrets/home-assistant/holidays>;
  # for example :
  # holidays = lib.flatten [
  #  (holiday-range "2020-06" 7 24)
  #  (holiday-range "2020-10" 10 16)
  #];
  holidays = lib.flatten (privateHolidays holiday-range);

in
{
  services.homeAssistantConfig = {

    binary_sensor = [
      {
        name = "before_workday";
        platform = "workday";
        country = "DE";
        province = "NW";
        workdays = [ "mon" "tue" "wed" "thu" "fri" ];
        days_offset = 1;
        add_holidays = holidays;
      }
      {
        name = "workday";
        platform = "workday";
        country = "DE";
        province = "NW";
        workdays = [ "mon" "tue" "wed" "thu" "fri" ];
        add_holidays = holidays;
      }
    ];

    homeassistant.customize = {
      "binary_sensor.workday" = {
        icon = "mdi:calendar";
        friendly_name = "Workday?";
      };
      "binary_sensor.before_workday" = {
        icon = "mdi:calendar";
        friendly_name = "Workday Tomorrow?";
      };
    };

    group = {
      today.entities =
        [ "binary_sensor.before_workday" "binary_sensor.workday" ];
    };

  };

}