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

-export([dns_lookup/2, discover_nodes/3]).
-export_type([lookup_error/0, ip_address/0]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

-type lookup_error() :: format_error |
    query_format_error |
    server_failure |
    no_such_domain |
    timeout |
    not_implemented |
    refused |
    bad_version |
    {posix_error, binary()} |
    unknown.

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

-file("src/barnacle/dns.gleam", 40).
?DOC(
    " Perform a DNS lookup against a hostname. This will return a list of IP\n"
    " addresses. Queries will be performed using the `A` and `AAAA` record types.\n"
).
-spec dns_lookup(binary(), integer()) -> {ok, list(ip_address())} |
    {error, lookup_error()}.
dns_lookup(Hostname, Timeout) ->
    gleam@result:'try'(
        barnacle_ffi:lookup_a(Hostname, Timeout),
        fun(A_records) ->
            A_records@1 = begin
                _pipe = A_records,
                gleam@list:map(
                    _pipe,
                    fun(Ip) ->
                        {A, B, C, D} = Ip,
                        {ip_v4, A, B, C, D}
                    end
                )
            end,
            gleam@result:'try'(
                barnacle_ffi:lookup_aaaa(Hostname, Timeout),
                fun(Aaaa_records) ->
                    Aaaa_records@1 = begin
                        _pipe@1 = Aaaa_records,
                        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,
                    {ok, lists:append(A_records@1, Aaaa_records@1)}
                end
            )
        end
    ).

-file("src/barnacle/dns.gleam", 65).
-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 erlang:integer_to_binary/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>>),
            string:lowercase(_pipe@4)
    end.

-file("src/barnacle/dns.gleam", 92).
?DOC(
    " Discover nodes using DNS. The first argument is the basename of the nodes.\n"
    " Currently, Barnacle only supports connecting to nodes with the same basename.\n"
    "\n"
    " The second argument is the hostname to query against. Both A and AAAA records\n"
    " will be queried. The final argument is an optional timeout for the DNS\n"
    " lookup. This defaults to 5000ms if not supplied.\n"
).
-spec discover_nodes(binary(), binary(), integer()) -> {ok,
        list(gleam@erlang@atom:atom_())} |
    {error, lookup_error()}.
discover_nodes(Basename, Hostname_query, Timeout) ->
    gleam@result:'try'(
        dns_lookup(Hostname_query, Timeout),
        fun(Ip_addresses) -> _pipe = Ip_addresses,
            _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} end
    ).