-module(docs@log_requests).
-compile([no_auto_import, nowarn_unused_vars]).

-export([middleware/1]).
-export_type([time_unit/0]).

-type time_unit() :: native | microsecond.

-spec format_log_line(
    gleam@http@request:request(any()),
    gleam@http@response:response(any()),
    integer()
) -> binary().
format_log_line(Request, Response, Elapsed) ->
    Elapsed@1 = case Elapsed > 1000 of
        true ->
            gleam@string:append(
                gleam@int:to_string(Elapsed div 1000),
                <<"ms"/utf8>>
            );

        false ->
            gleam@string:append(gleam@int:to_string(Elapsed), <<"µs"/utf8>>)
    end,
    gleam@string:concat(
        [begin
                _pipe = erlang:element(2, Request),
                _pipe@1 = gleam@http:method_to_string(_pipe),
                gleam@string:uppercase(_pipe@1)
            end,
            <<" "/utf8>>,
            erlang:element(8, Request),
            <<" "/utf8>>,
            gleam@int:to_string(erlang:element(2, Response)),
            <<" sent in "/utf8>>,
            Elapsed@1]
    ).

-spec middleware(
    fun((gleam@http@request:request(NPN)) -> gleam@http@response:response(NPO))
) -> fun((gleam@http@request:request(NPN)) -> gleam@http@response:response(NPO)).
middleware(Service) ->
    fun(Request) ->
        Before = erlang:monotonic_time(),
        Response = Service(Request),
        Elapsed = erlang:convert_time_unit(
            erlang:monotonic_time() - Before,
            native,
            microsecond
        ),
        docs@utils@logger:info(format_log_line(Request, Response, Elapsed)),
        Response
    end.