-module(dateformat@internal@util).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/dateformat/internal/util.gleam").
-export([to_ordinal/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(false).

-file("src/dateformat/internal/util.gleam", 3).
?DOC(false).
-spec to_ordinal(integer()) -> binary().
to_ordinal(Num) ->
    case Num of
        N when N > 100 ->
            <<(erlang:integer_to_binary(Num div 100))/binary,
                (to_ordinal(Num rem 100))/binary>>;

        N@1 when (N@1 > 3) andalso (N@1 < 20) ->
            <<(erlang:integer_to_binary(Num))/binary, "th"/utf8>>;

        N@2 ->
            <<(erlang:integer_to_binary(Num))/binary, (case N@2 rem 10 of
                    1 ->
                        <<"st"/utf8>>;

                    2 ->
                        <<"nd"/utf8>>;

                    3 ->
                        <<"rd"/utf8>>;

                    _ ->
                        <<"th"/utf8>>
                end)/binary>>
    end.