%%%------------------------------------------------------------------------
%% Copyright 2021, OpenTelemetry Authors
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% @doc Module for setting the global limits for the number of attributes,
%% events and links on a Span.
%% @end
%%%-------------------------------------------------------------------------
-module(otel_span_limits).

-export([get/0,
         set/1,
         attribute_count_limit/0,
         attribute_value_length_limit/0,
         event_count_limit/0,
         link_count_limit/0,
         attribute_per_event_limit/0,
         attribute_per_link_limit/0]).

-include("otel_span.hrl").

-define(SPAN_LIMITS_KEY, {?MODULE, span_limits}).

-spec get() -> #span_limits{}.
get() ->
    persistent_term:get(?SPAN_LIMITS_KEY).

%% -spec set(#{attribute_count_limit => integer(),
%%             attribute_value_length_limit => integer() | infinity,
%%             event_count_limit => integer(),
%%             link_count_limit => integer(),
%%             attribute_per_event_limit => integer(),
%%             attribute_per_link_limit => integer()}) -> ok.
-spec set(otel_configuration:t()) -> ok.
set(Opts) ->
    SpanLimits = maps:fold(fun(attribute_count_limit, AttributeCountLimit, Acc) ->
                                   Acc#span_limits{attribute_count_limit=AttributeCountLimit};
                              (attribute_value_length_limit, AttributeValueLengthLimit, Acc) ->
                                   Acc#span_limits{attribute_value_length_limit=AttributeValueLengthLimit};
                              (event_count_limit, EventCountLimit, Acc) ->
                                   Acc#span_limits{event_count_limit=EventCountLimit};
                              (link_count_limit, LinkCountLimit, Acc) ->
                                   Acc#span_limits{link_count_limit=LinkCountLimit};
                              (attribute_per_event_limit, AttributePerEventLimit, Acc) ->
                                   Acc#span_limits{attribute_per_event_limit=AttributePerEventLimit};
                              (attribute_per_link_limit, AttributePerLinkLimit, Acc) ->
                                   Acc#span_limits{attribute_per_link_limit=AttributePerLinkLimit};
                              (_, _, Acc) ->
                                   Acc
                           end, #span_limits{}, Opts),
    persistent_term:put(?SPAN_LIMITS_KEY, SpanLimits).

attribute_count_limit() ->
    get_limit(attribute_count_limit, ?MODULE:get()).

attribute_value_length_limit() ->
    get_limit(attribute_value_length_limit, ?MODULE:get()).

event_count_limit() ->
    get_limit(event_count_limit, ?MODULE:get()).

link_count_limit() ->
    get_limit(link_count_limit, ?MODULE:get()).

attribute_per_event_limit() ->
    get_limit(attribute_per_event_limit, ?MODULE:get()).

attribute_per_link_limit() ->
    get_limit(attribute_per_link_limit, ?MODULE:get()).

get_limit(attribute_count_limit, #span_limits{attribute_count_limit=AttributeCountLimit}) ->
    AttributeCountLimit;
get_limit(attribute_value_length_limit, #span_limits{attribute_value_length_limit=AttributeValueLengthLimit}) ->
    AttributeValueLengthLimit;
get_limit(event_count_limit, #span_limits{event_count_limit=EventCountLimit}) ->
    EventCountLimit;
get_limit(link_count_limit, #span_limits{link_count_limit=LinkCountLimit}) ->
    LinkCountLimit;
get_limit(attribute_per_event_limit, #span_limits{attribute_per_event_limit=AttributePerEventLimit}) ->
    AttributePerEventLimit;
get_limit(attribute_per_link_limit, #span_limits{attribute_per_link_limit=AttributePerLinkLimit}) ->
    AttributePerLinkLimit.