domain_puns

-module(domain_puns@punycode).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/domain_puns/punycode.gleam").
-export([matches_domain/1]).

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

?MODULEDOC(" Module for working with punycode.\n").

-file("src/domain_puns/punycode.gleam", 10).
?DOC(
    " Checks if a domain string is a punycode domain. If it is, it returns the punycode\n"
    " string with the leading prefix for internationalized domains removed.\n"
).
-spec matches_domain(binary()) -> {ok, binary()} | {error, nil}.
matches_domain(Domain) ->
    Lower = string:lowercase(Domain),
    case gleam_stdlib:string_starts_with(Lower, <<"xn--"/utf8>>) of
        true ->
            _pipe = gleam_stdlib:string_remove_prefix(Lower, <<"xn--"/utf8>>),
            {ok, _pipe};

        false ->
            {error, nil}
    end.