-module(dot_env@internal@parser).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([parse/1]).

-spec expand_new_lines(binary()) -> binary().
expand_new_lines(Value) ->
    _pipe = gleam@string:replace(Value, <<"\\n"/utf8>>, <<"\n"/utf8>>),
    gleam@string:replace(_pipe, <<"\\r"/utf8>>, <<"\r"/utf8>>).

-spec extract_value_from_match(gleam@regex:match()) -> {ok, binary()} |
    {error, binary()}.
extract_value_from_match(Match) ->
    _pipe = gleam@list:at(erlang:element(3, Match), 1),
    _pipe@1 = gleam@result:unwrap(_pipe, {some, erlang:element(2, Match)}),
    _pipe@2 = gleam@option:unwrap(_pipe@1, <<""/utf8>>),
    {ok, _pipe@2}.

-spec remove_surrounding_quotes(binary()) -> {ok, binary()} | {error, binary()}.
remove_surrounding_quotes(Value) ->
    case gleam@regex:compile(
        <<"^(['\"`])([\\s\\S]*)\\1$"/utf8>>,
        {options, true, true}
    ) of
        {ok, Re} ->
            case gleam@regex:scan(Re, Value) of
                [Match] ->
                    extract_value_from_match(Match);

                [_ | _] ->
                    {error,
                        <<"Multiple quotes found in value: "/utf8,
                            Value/binary>>};

                [] ->
                    {ok, Value}
            end;

        {error, _} ->
            {error,
                <<"Regex error at extract_within_quotes, this is a bug, please create an issue"/utf8>>}
    end.

-spec normalize_value(binary()) -> {ok, binary()} | {error, binary()}.
normalize_value(Value) ->
    Has_double_quotes = gleam@string:starts_with(Value, <<"\""/utf8>>),
    gleam@result:'try'(
        begin
            _pipe = gleam@string:trim(Value),
            remove_surrounding_quotes(_pipe)
        end,
        fun(Value@1) ->
            gleam@bool:guard(
                not Has_double_quotes,
                {ok, Value@1},
                fun() -> {ok, expand_new_lines(Value@1)} end
            )
        end
    ).

-spec is_valid_key(binary()) -> boolean().
is_valid_key(Key) ->
    case gleam@regex:compile(
        <<"^[a-zA-Z_]+[a-zA-Z0-9_]*$"/utf8>>,
        {options, false, true}
    ) of
        {ok, Re} ->
            gleam@regex:check(Re, Key);

        {error, _} ->
            false
    end.

-spec to_pairs(list(binary()), list({binary(), binary()})) -> {ok,
        list({binary(), binary()})} |
    {error, binary()}.
to_pairs(Raw_list, State) ->
    case Raw_list of
        [Key, Value | Rest] ->
            case is_valid_key(Key) of
                true ->
                    gleam@result:'try'(
                        normalize_value(Value),
                        fun(Normalized_value) ->
                            to_pairs(
                                Rest,
                                gleam@list:concat(
                                    [State, [{Key, Normalized_value}]]
                                )
                            )
                        end
                    );

                false ->
                    to_pairs(Rest, State)
            end;

        [Key@1] ->
            gleam@bool:guard(
                not is_valid_key(Key@1),
                {ok, State},
                fun() ->
                    {ok, gleam@list:concat([State, [{Key@1, <<""/utf8>>}]])}
                end
            );

        [] ->
            {ok, State};

        _ ->
            {ok, State}
    end.

-spec is_comment(binary()) -> boolean().
is_comment(Line) ->
    case gleam@string:trim(Line) of
        <<"#"/utf8, _/binary>> ->
            true;

        _ ->
            false
    end.

-spec replace(binary(), binary(), binary()) -> binary().
replace(Str, Regex, With) ->
    case gleam@regex:compile(Regex, {options, true, true}) of
        {ok, Re} ->
            _pipe = gleam@regex:split(Re, Str),
            _pipe@1 = gleam@string:join(_pipe, With),
            gleam@string:trim(_pipe@1);

        {error, _} ->
            Str
    end.

-spec pop_first_if_empty(gleam@queue:queue(binary())) -> gleam@queue:queue(binary()).
pop_first_if_empty(Items) ->
    case gleam@queue:pop_front(Items) of
        {ok, {First, _}} ->
            gleam@bool:guard(
                First /= <<""/utf8>>,
                Items,
                fun() -> case gleam@queue:pop_front(Items) of
                        {ok, {_, Rest}} ->
                            Rest;

                        {error, _} ->
                            Items
                    end end
            );

        {error, _} ->
            Items
    end.

-spec pop_last_if_empty(gleam@queue:queue(binary())) -> gleam@queue:queue(binary()).
pop_last_if_empty(Items) ->
    case gleam@queue:pop_back(Items) of
        {ok, {Last, _}} ->
            gleam@bool:guard(
                Last /= <<""/utf8>>,
                Items,
                fun() -> case gleam@queue:pop_back(Items) of
                        {ok, {_, Rest}} ->
                            Rest;

                        {error, _} ->
                            Items
                    end end
            );

        {error, _} ->
            Items
    end.

-spec lines_to_list(binary()) -> list(binary()).
lines_to_list(Text) ->
    _pipe = case gleam@regex:compile(
        <<"(?:^|^)\\s*(?:export\\s+)?([\\w.-]+)(?:\\s*=\\s*?|:\\s+?)(\\s*'(?:\\\\'|[^'])*'|\\s*\"(?:\\\\\"|[^\"])*\"|\\s*`(?:\\\\`|[^`])*`|[^#\\r\\n]+)?\\s*(?:#.*)?(?:$|$)"/utf8>>,
        {options, true, true}
    ) of
        {ok, Re} ->
            gleam@regex:split(Re, Text);

        {error, _} ->
            []
    end,
    gleam@list:filter(
        _pipe,
        fun(Line) -> (Line /= <<"\n"/utf8>>) andalso not is_comment(Line) end
    ).

-spec parse(binary()) -> {ok, list({binary(), binary()})} | {error, binary()}.
parse(Text) ->
    Lines = replace(Text, <<"\r\n?"/utf8>>, <<"\n"/utf8>>),
    gleam@result:'try'(
        begin
            _pipe = lines_to_list(Lines),
            _pipe@1 = gleam@queue:from_list(_pipe),
            _pipe@2 = pop_first_if_empty(_pipe@1),
            _pipe@3 = pop_last_if_empty(_pipe@2),
            _pipe@4 = gleam@queue:to_list(_pipe@3),
            to_pairs(_pipe@4, [])
        end,
        fun(Env_map) -> {ok, Env_map} end
    ).