%%--------------------------------------------------------------------
%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
%%
%% 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.
%%--------------------------------------------------------------------

-module(emqx_retainer_SUITE).

-compile(export_all).
-compile(nowarn_export_all).

-define(APP, emqx).

-include_lib("eunit/include/eunit.hrl").
-include_lib("common_test/include/ct.hrl").

all() -> emqx_ct:all(?MODULE).

%%--------------------------------------------------------------------
%% Setups
%%--------------------------------------------------------------------

init_per_suite(Config) ->
    emqx_ct_helpers:start_apps([emqx_retainer]),
    Config.

end_per_suite(_Config) ->
    emqx_ct_helpers:stop_apps([emqx_retainer]).

init_per_testcase(TestCase, Config) ->
    emqx_retainer:clean(<<"#">>),
    case TestCase of
        t_message_expiry_2 ->
            application:set_env(emqx_retainer, expiry_interval, 2000);
        t_stop_publish_clear_msg ->
            application:set_env(emqx_retainer, stop_publish_clear_msg, true);
        _ ->
            application:set_env(emqx_retainer, expiry_interval, 0)
    end,
    application:stop(emqx_retainer),
    application:ensure_all_started(emqx_retainer),
    Config.

%%--------------------------------------------------------------------
%% Test Cases
%%--------------------------------------------------------------------

t_store_and_clean(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),

    emqtt:publish(C1, <<"retained">>, <<"this is a retained message">>, [{qos, 0}, {retain, true}]),
    timer:sleep(100),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(1, length(receive_messages(1))),

    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained">>),

    emqtt:publish(C1, <<"retained">>, <<"">>, [{qos, 0}, {retain, true}]),
    timer:sleep(100),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(0, length(receive_messages(1))),

    ok = emqtt:disconnect(C1).

t_retain_handling(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),

    emqtt:publish(C1, <<"retained">>, <<"this is a retained message">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(1, length(receive_messages(1))),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(1, length(receive_messages(1))),
    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained">>),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 1}]),
    ?assertEqual(1, length(receive_messages(1))),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 1}]),
    ?assertEqual(0, length(receive_messages(1))),
    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained">>),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 2}]),
    ?assertEqual(0, length(receive_messages(1))),

    emqtt:publish(C1, <<"retained">>, <<"">>, [{qos, 0}, {retain, true}]),
    ok = emqtt:disconnect(C1).

t_wildcard_subscription(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),
    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/1">>, <<"this is a retained message 1">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/a/b/c">>, <<"this is a retained message 2">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1,  <<"retained/+">>, 0),
    {ok, #{}, [0]} = emqtt:subscribe(C1,  <<"retained/+/b/#">>, 0),
    ?assertEqual(3, length(receive_messages(3))),

    emqtt:publish(C1, <<"retained/0">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/1">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/a/b/c">>, <<"">>, [{qos, 0}, {retain, true}]),
    ok = emqtt:disconnect(C1).

t_message_expiry(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),

    emqtt:publish(C1, <<"retained/0">>, #{'Message-Expiry-Interval' => 0}, <<"don't expire">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/1">>, #{'Message-Expiry-Interval' => 2}, <<"expire">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/2">>, #{'Message-Expiry-Interval' => 5}, <<"don't expire">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/3">>, <<"don't expire">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"$SYS/retained/4">>, <<"don't expire">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/+">>, 0),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"$SYS/retained/+">>, 0),
    ?assertEqual(5, length(receive_messages(5))),
    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained/+">>),
    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"$SYS/retained/+">>),

    timer:sleep(3000),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/+">>, 0),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"$SYS/retained/+">>, 0),
    ?assertEqual(4, length(receive_messages(5))),

    emqtt:publish(C1, <<"retained/0">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/1">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/2">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/3">>, <<"">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"$SYS/retained/4">>, <<"">>, [{qos, 0}, {retain, true}]),

    ok = emqtt:disconnect(C1).

t_message_expiry_2(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),
    emqtt:publish(C1, <<"retained">>, <<"expire">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(1, length(receive_messages(1))),
    timer:sleep(3000),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(0, length(receive_messages(1))),
    {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained">>),

    emqtt:publish(C1, <<"retained">>, <<"">>, [{qos, 0}, {retain, true}]),

    ok = emqtt:disconnect(C1).

t_clean(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),
    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/1">>, <<"this is a retained message 1">>, [{qos, 0}, {retain, true}]),
    emqtt:publish(C1, <<"retained/test/0">>, <<"this is a retained message 2">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(3, length(receive_messages(3))),

    1 = emqx_retainer:clean(<<"retained/test/0">>),
    2 = emqx_retainer:clean(<<"retained/+">>),
    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(0, length(receive_messages(3))),

    ok = emqtt:disconnect(C1).

t_stop_publish_clear_msg(_) ->
    {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
    {ok, _} = emqtt:connect(C1),
    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),

    {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
    ?assertEqual(1, length(receive_messages(1))),

    emqtt:publish(C1, <<"retained/0">>, <<"">>, [{qos, 0}, {retain, true}]),
    ?assertEqual(0, length(receive_messages(1))),

    ok = emqtt:disconnect(C1).

%%--------------------------------------------------------------------
%% Helper functions
%%--------------------------------------------------------------------

receive_messages(Count) ->
    receive_messages(Count, []).
receive_messages(0, Msgs) ->
    Msgs;
receive_messages(Count, Msgs) ->
    receive
        {publish, Msg} ->
            ct:log("Msg: ~p ~n", [Msg]),
            receive_messages(Count-1, [Msg|Msgs]);
        Other ->
            ct:log("Other Msg: ~p~n",[Other]),
            receive_messages(Count, Msgs)
    after 2000 ->
            Msgs
    end.