-module(gdav@get_etags).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/gdav/get_etags.gleam").
-export([request/1, build/2, response/1]).
-export_type([request_builder/0]).

-type request_builder() :: {request_builder, binary()}.

-file("src/gdav/get_etags.gleam", 14).
-spec request(binary()) -> request_builder().
request(Collection_path) ->
    {request_builder, Collection_path}.

-file("src/gdav/get_etags.gleam", 18).
-spec build(request_builder(), gdav:credentials()) -> gleam@http@request:request(binary()).
build(Builder, Credentials) ->
    Headers = [{<<"Depth"/utf8>>, <<"1"/utf8>>},
        {<<"Prefer"/utf8>>, <<"return-minimal"/utf8>>},
        {<<"Content-Type"/utf8>>, <<"application/xml; charset=utf-8"/utf8>>}],
    Body = <<<<<<<<<<<<<<"<c:calendar-query xmlns:d=\"DAV:\" xmlns:c=\"urn:ietf:params:xml:ns:caldav\">"/utf8,
                                "<d:prop>"/utf8>>/binary,
                            "<d:getetag />"/utf8>>/binary,
                        "</d:prop>"/utf8>>/binary,
                    "<c:filter>"/utf8>>/binary,
                "<c:comp-filter name=\"VCALENDAR\" />"/utf8>>/binary,
            "</c:filter>"/utf8>>/binary,
        "</c:calendar-query>"/utf8>>,
    gdav@internal:request(
        Credentials,
        {other, <<"REPORT"/utf8>>},
        erlang:element(2, Builder),
        Headers,
        Body
    ).

-file("src/gdav/get_etags.gleam", 46).
-spec response(gleam@http@response:response(binary())) -> {ok,
        list({binary(), binary()})} |
    {error, gdav:dav_error()}.
response(Res) ->
    case erlang:element(2, Res) of
        S when (S >= 200) andalso (S < 300) ->
            gleam@result:'try'(
                gdav@internal@xml:parse_multistatus(erlang:element(4, Res)),
                fun(Responses) ->
                    Pairs = gleam@list:filter_map(
                        Responses,
                        fun(R) ->
                            case gdav@internal@xml:find_text(
                                erlang:element(4, R),
                                <<"DAV:"/utf8>>,
                                <<"getetag"/utf8>>
                            ) of
                                {ok, Etag} when Etag =/= <<""/utf8>> ->
                                    {ok, {erlang:element(2, R), Etag}};

                                _ ->
                                    {error, nil}
                            end
                        end
                    ),
                    {ok, Pairs}
                end
            );

        404 ->
            {error, not_found};

        401 ->
            {error, authentication_failed};

        403 ->
            {error, authentication_failed};

        _ ->
            {error, {unexpected_response, Res}}
    end.