config/modules/darwin/karabiner.nix

let
  numbers = [
    "1"
    "2"
    "3"
    "4"
    "5"
    "6"
    "7"
    "8"
    "9"
    "0"
  ];

  number_to_symbol = num: {
    type = "basic";
    from = {
      key_code = num;
      modifiers = {
        optional = [ "caps_lock" ];
      };
    };
    to = [
      {
        key_code = num;
        modifiers = [ "left_shift" ];
      }
    ];
  };

  symbol_to_number = num: {
    type = "basic";
    from = {
      key_code = num;
      modifiers = {
        mandatory = [ "left_shift" ];
        optional = [ "caps_lock" ];
      };
    };
    to = [
      {
        key_code = num;
      }
    ];
  };

  manipulators = builtins.concatLists (
    map (n: [
      (number_to_symbol n)
      (symbol_to_number n)
    ]) numbers
  );

  simple_modifications = [
    {
      from.apple_vendor_top_case_key_code = "keyboard_fn";
      to = [ { key_code = "left_control"; } ];
    }
    {
      from.key_code = "left_control";
      to = [ { apple_vendor_top_case_key_code = "keyboard_fn"; } ];
    }
  ];

  complex_modifications = {
    name = "Complex Modifications";
    rules = [
      # {
      #   description = "Change numbers to symbols and vice versa";
      #   manipulators = manipulators;
      # }
      {
        description = "Toggle Focus Mode with F6";
        manipulators = [
          {
            from = {
              "key_code" = "f6";
            };
            to = [ { "shell_command" = "shortcuts run 'Reduced Interruptions'"; } ];
            type = "basic";
          }
        ];
      }
    ];
  };

  config = builtins.toJSON {
    global.show_in_menu_bar = false;

    profiles = [
      {
        name = "default";
        selected = true;
        virtual_hid_keyboard.keyboard_type_v2 = "ansi";
        inherit simple_modifications;
        inherit complex_modifications;

        devices = [
          {
            identifiers.is_keyboard = true;
          }
        ];
      }
    ];
  };
in
{
  home-manager.sharedModules = [
    {
      home.file.".config/karabiner/karabiner.json" = {
        force = true;
        text = config;
      };
    }
  ];
}