-module(utils).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([get_ansi_code/1]).

-spec hex_value(binary()) -> {ok, integer()} | {error, nil}.
hex_value(Value) ->
    case Value of
        <<"0"/utf8>> ->
            {ok, 0};

        <<"1"/utf8>> ->
            {ok, 1};

        <<"2"/utf8>> ->
            {ok, 2};

        <<"3"/utf8>> ->
            {ok, 3};

        <<"4"/utf8>> ->
            {ok, 4};

        <<"5"/utf8>> ->
            {ok, 5};

        <<"6"/utf8>> ->
            {ok, 6};

        <<"7"/utf8>> ->
            {ok, 7};

        <<"8"/utf8>> ->
            {ok, 8};

        <<"9"/utf8>> ->
            {ok, 9};

        <<"a"/utf8>> ->
            {ok, 10};

        <<"A"/utf8>> ->
            {ok, 10};

        <<"b"/utf8>> ->
            {ok, 11};

        <<"B"/utf8>> ->
            {ok, 11};

        <<"c"/utf8>> ->
            {ok, 12};

        <<"C"/utf8>> ->
            {ok, 12};

        <<"d"/utf8>> ->
            {ok, 13};

        <<"D"/utf8>> ->
            {ok, 13};

        <<"e"/utf8>> ->
            {ok, 14};

        <<"E"/utf8>> ->
            {ok, 14};

        <<"f"/utf8>> ->
            {ok, 15};

        <<"F"/utf8>> ->
            {ok, 15};

        _ ->
            {error, nil}
    end.

-spec parse_hex_code_aux(list(binary()), list(integer())) -> list(integer()).
parse_hex_code_aux(Char_list, Int_list) ->
    case Char_list of
        [] ->
            Int_list;

        [_] ->
            Int_list;

        [First, Second | Remaining] ->
            First_result = hex_value(First),
            Second_result = hex_value(Second),
            case {First_result, Second_result} of
                {{ok, First_value}, {ok, Second_value}} ->
                    parse_hex_code_aux(
                        Remaining,
                        lists:append(
                            Int_list,
                            [(16 * First_value) + Second_value]
                        )
                    );

                {_, _} ->
                    []
            end
    end.

-spec parse_hex_code(list(binary())) -> list(integer()).
parse_hex_code(Value) ->
    parse_hex_code_aux(Value, []).

-spec parse_color_aux(list(integer()), binary()) -> binary().
parse_color_aux(Value, String) ->
    case Value of
        [Last] ->
            <<<<String/binary, (gleam@int:to_string(Last))/binary>>/binary,
                "m"/utf8>>;

        [First | Remaining] ->
            parse_color_aux(
                Remaining,
                <<<<String/binary, (gleam@int:to_string(First))/binary>>/binary,
                    ";"/utf8>>
            );

        [] ->
            String;

        _ ->
            String
    end.

-spec parse_color(types:color()) -> {ok, binary()} | {error, nil}.
parse_color(Color) ->
    Char_list = gleam@string:to_graphemes(erlang:element(2, Color)),
    case gleam@list:pop(Char_list, fun(_) -> true end) of
        {ok, {<<"#"/utf8>>, Hex_code}} ->
            case erlang:length(Hex_code) of
                6 ->
                    {ok, parse_color_aux(parse_hex_code(Hex_code), <<""/utf8>>)};

                _ ->
                    {error, nil}
            end;

        {error, _} ->
            {error, nil};

        _ ->
            {error, nil}
    end.

-spec get_ansi_code(types:color()) -> binary().
get_ansi_code(Color) ->
    case gleam@string:lowercase(erlang:element(2, Color)) of
        <<"clear"/utf8>> ->
            <<"clear"/utf8>>;

        _ ->
            case parse_color(Color) of
                {ok, Value} ->
                    Value;

                {error, _} ->
                    <<"clear"/utf8>>
            end
    end.