nixos-configs/devices/homie/modules/home-assistant/bluetooth.nix

{
  config,
  lib,
  pkgs,
  ...
}: {
  # Turn On the speaker automatically when openwakeword is used
  services.home-assistant = {
    extraComponents = [
      "mpd"

      # BT components
      "ibeacon"
      "led_ble"
      "kegtron"
      "xiaomi_ble"
    ];

    config = {
      shell_command.turn_on_ue = lib.getExe (pkgs.writeShellApplication {
        name = "turnOnUE";

        runtimeInputs = [config.hardware.bluetooth.package];

        text = ''
          cmd=0x0003
          bt_device_addr=88:C6:26:93:4B:77

          # This is the MAC address on the first line of `bluetootctl show`
          # without the `:` and with `01` added at the end
          bt_controller_addr=E848B8C8200001

          exec gatttool -b $bt_device_addr --char-write-req --handle=$cmd --value=$bt_controller_addr
        '';
      });

      automation = [
        {
          alias = "Turn On UE";
          mode = "single";
          trigger = [
            {
              platform = "state";
              entity_id = "wake_word.openwakeword";
            }
          ];
          condition = [];
          action = [
            {
              action = "shell_command.turn_on_ue";
              metadata = {};
              data = {};
            }
          ];
        }
      ];
    };
  };
}