-module(gleam@path).
-compile(no_auto_import).

-export([from_string/1, join/2, to_string/1, normalize/1]).
-export_type([path/0, path_filter/0]).

-type path() :: {absolute, list(binary())} | {relative, list(binary())}.

-type path_filter() :: up | skip | include.

-spec filter_segment_list(path()) -> path().
filter_segment_list(Path) ->
    Constructor = case Path of
        {absolute, _@1} ->
            fun(A) -> {absolute, A} end;

        {relative, _@2} ->
            fun(A) -> {relative, A} end
    end,
    Segments = erlang:element(2, Path),
    _pipe = Segments,
    _pipe@1 = gleam@list:fold(
        _pipe,
        [],
        fun(Segments@1, Segment) -> case filter_segment(Segment) of
                up ->
                    case {Path,
                          gleam@list:all(
                              Segments@1,
                              fun(Segment@1) -> Segment@1 =:= <<".."/utf8>> end
                          )} of
                        {{relative, _@3}, true} ->
                            gleam@list:append(Segments@1, [<<".."/utf8>>]);

                        {_@4, _@5} ->
                            gleam@list:take(
                                Segments@1,
                                gleam@list:length(Segments@1)
                                - 1
                            )
                    end;

                skip ->
                    Segments@1;

                include ->
                    gleam@list:append(Segments@1, [Segment])
            end end
    ),
    Constructor(_pipe@1).

-spec filter_segment(binary()) -> path_filter().
filter_segment(Segment) ->
    case Segment of
        <<""/utf8>> ->
            skip;

        <<"."/utf8>> ->
            skip;

        <<".."/utf8>> ->
            up;

        _@1 ->
            include
    end.

-spec from_string(binary()) -> path().
from_string(Base) ->
    Constructor = case gleam@string:starts_with(Base, <<"/"/utf8>>) of
        true ->
            fun(A) -> {absolute, A} end;

        false ->
            fun(A) -> {relative, A} end
    end,
    _pipe = Base,
    _pipe@1 = gleam@string:split(_pipe, <<"/"/utf8>>),
    _pipe@2 = Constructor(_pipe@1),
    filter_segment_list(_pipe@2).

-spec join(path(), binary()) -> path().
join(Path, Piece) ->
    Constructor = case Path of
        {absolute, _@1} ->
            fun(A) -> {absolute, A} end;

        {relative, _@2} ->
            fun(A) -> {relative, A} end
    end,
    Segments = erlang:element(2, Path),
    _pipe = Piece,
    _pipe@1 = gleam@string:split(_pipe, <<"/"/utf8>>),
    _pipe@2 = gleam@list:append(Segments, _pipe@1),
    _pipe@3 = Constructor(_pipe@2),
    filter_segment_list(_pipe@3).

-spec to_string(path()) -> binary().
to_string(Path) ->
    Joined_segments = gleam@string:join(erlang:element(2, Path), <<"/"/utf8>>),
    case Path of
        {absolute, _@1} ->
            gleam@string:concat([<<"/"/utf8>>, Joined_segments]);

        {relative, _@2} ->
            Joined_segments
    end.

-spec normalize(binary()) -> binary().
normalize(Messy) ->
    _pipe = Messy,
    _pipe@1 = from_string(_pipe),
    to_string(_pipe@1).