-module(barnacle@internal@dns).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([discover_nodes/2]).
-export_type([ip_address/0]).

-type ip_address() :: {ip_v4, integer(), integer(), integer(), integer()} |
    {ip_v6,
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer()}.

-spec lookup_ip(binary()) -> list(ip_address()).
lookup_ip(Hostname) ->
    A_records = begin
        _pipe = barnacle_ffi:lookup_a(Hostname),
        gleam@list:map(
            _pipe,
            fun(Ip) ->
                {A, B, C, D} = Ip,
                {ip_v4, A, B, C, D}
            end
        )
    end,
    Aaaa_records = begin
        _pipe@1 = barnacle_ffi:lookup_aaaa(Hostname),
        gleam@list:map(
            _pipe@1,
            fun(Ip@1) ->
                {A@1, B@1, C@1, D@1, E, F, G, H} = Ip@1,
                {ip_v6, A@1, B@1, C@1, D@1, E, F, G, H}
            end
        )
    end,
    gleam@list:concat([A_records, Aaaa_records]).

-spec format_ip_address(ip_address()) -> binary().
format_ip_address(Ip) ->
    case Ip of
        {ip_v4, A, B, C, D} ->
            _pipe = [A, B, C, D],
            _pipe@1 = gleam@list:map(_pipe, fun gleam@int:to_string/1),
            gleam@string:join(_pipe@1, <<"."/utf8>>);

        {ip_v6, A@1, B@1, C@1, D@1, E, F, G, H} ->
            _pipe@2 = [A@1, B@1, C@1, D@1, E, F, G, H],
            _pipe@3 = gleam@list:map(_pipe@2, fun(Value) -> case Value of
                        0 ->
                            <<""/utf8>>;

                        _ ->
                            gleam@int:to_base16(Value)
                    end end),
            _pipe@4 = gleam@string:join(_pipe@3, <<":"/utf8>>),
            gleam@string:lowercase(_pipe@4)
    end.

-spec discover_nodes(binary(), binary()) -> {ok,
        list(gleam@erlang@atom:atom_())} |
    {error, nil}.
discover_nodes(Basename, Hostname_query) ->
    _pipe = lookup_ip(Hostname_query),
    _pipe@2 = gleam@list:map(
        _pipe,
        fun(Ip) ->
            Ip_string = format_ip_address(Ip),
            _pipe@1 = (<<<<Basename/binary, "@"/utf8>>/binary,
                Ip_string/binary>>),
            erlang:binary_to_atom(_pipe@1)
        end
    ),
    {ok, _pipe@2}.