-module(tubes@msg).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([parse/1]).
-export_type([irc_message/0, message_source/0]).

-type irc_message() :: {irc_message,
        gleam@dict:dict(binary(), gleam@option:option(binary())),
        gleam@option:option(message_source()),
        binary(),
        list(binary())}.

-type message_source() :: {server, binary()} |
    {nick, binary(), binary(), binary()}.

-spec take_if_prefix(binary(), binary(), FQZ, fun((binary()) -> FQZ)) -> {FQZ,
    binary()}.
take_if_prefix(Msg, Prefix, Default, Callback) ->
    Msg@1 = gleam@string:trim_left(Msg),
    case {gleam@string:first(Msg@1),
        gleam@string:split_once(Msg@1, <<" "/utf8>>)} of
        {{ok, P}, {ok, {X, Rest}}} when P =:= Prefix ->
            Res = begin
                _pipe = X,
                _pipe@1 = gleam@string:drop_left(_pipe, 1),
                Callback(_pipe@1)
            end,
            {Res, Rest};

        {_, _} ->
            {Default, Msg@1}
    end.

-spec escape_tag(binary()) -> binary().
escape_tag(X) ->
    _pipe = X,
    _pipe@1 = gleam@string:replace(_pipe, <<"\\:"/utf8>>, <<";"/utf8>>),
    _pipe@2 = gleam@string:replace(_pipe@1, <<"\\s"/utf8>>, <<" "/utf8>>),
    _pipe@3 = gleam@string:replace(_pipe@2, <<"\\\\"/utf8>>, <<"\\"/utf8>>),
    _pipe@4 = gleam@string:replace(_pipe@3, <<"\\r"/utf8>>, <<"\r"/utf8>>),
    gleam@string:replace(_pipe@4, <<"\\n"/utf8>>, <<"\n"/utf8>>).

-spec parse_single_tag(binary()) -> {binary(), gleam@option:option(binary())}.
parse_single_tag(X) ->
    case gleam@string:split_once(X, <<"="/utf8>>) of
        {ok, {K, V}} ->
            {escape_tag(K), {some, escape_tag(V)}};

        {error, _} ->
            {escape_tag(X), none}
    end.

-spec parse_tags(binary()) -> gleam@dict:dict(binary(), gleam@option:option(binary())).
parse_tags(Tags) ->
    _pipe = Tags,
    _pipe@1 = gleam@string:split(_pipe, <<";"/utf8>>),
    _pipe@2 = gleam@list:map(_pipe@1, fun parse_single_tag/1),
    maps:from_list(_pipe@2).

-spec parse_source(binary()) -> gleam@option:option(message_source()).
parse_source(Source) ->
    {some, case gleam@string:split_once(Source, <<"!"/utf8>>) of
            {ok, {Nick, Rest}} ->
                case gleam@string:split_once(Rest, <<"@"/utf8>>) of
                    {ok, {User, Host}} ->
                        {nick, Nick, User, Host};

                    _ ->
                        {server, Source}
                end;

            _ ->
                {server, Source}
        end}.

-spec parse_params(binary()) -> list(binary()).
parse_params(Params) ->
    case {gleam@string:split_once(Params, <<" :"/utf8>>),
        gleam@string:starts_with(Params, <<":"/utf8>>)} of
        {{ok, {Rest, Long}}, _} ->
            _pipe = gleam@string:split(Rest, <<" "/utf8>>),
            lists:append(_pipe, [Long]);

        {_, true} ->
            [gleam@string:drop_left(Params, 1)];

        {_, _} ->
            _pipe@1 = gleam@string:split(Params, <<" "/utf8>>),
            gleam@list:filter(_pipe@1, fun(X) -> X /= <<""/utf8>> end)
    end.

-spec parse(binary()) -> irc_message().
parse(Msg) ->
    {Tags, Msg@1} = take_if_prefix(
        Msg,
        <<"@"/utf8>>,
        gleam@dict:new(),
        fun parse_tags/1
    ),
    {Source, Msg@2} = take_if_prefix(
        Msg@1,
        <<":"/utf8>>,
        none,
        fun parse_source/1
    ),
    {Cmd, Msg@3} = begin
        _pipe = gleam@string:split_once(Msg@2, <<" "/utf8>>),
        gleam@result:unwrap(_pipe, {Msg@2, <<""/utf8>>})
    end,
    Params = parse_params(Msg@3),
    {irc_message, Tags, Source, Cmd, Params}.