%%--------------------------------------------------------------------
%% Copyright (c) 2023-2024 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.
%%--------------------------------------------------------------------

%% @doc The module which knows everything about actions.

%% NOTE: it does not cover the V1 bridges.

-module(emqx_action_info).

-export([
    action_type_to_connector_type/1,
    action_type_to_bridge_v1_type/2,
    bridge_v1_type_to_action_type/1,
    bridge_v1_type_name/1,
    is_action_type/1,
    is_source/1,
    is_action/1,
    registered_schema_modules_actions/0,
    registered_schema_modules_sources/0,
    connector_action_config_to_bridge_v1_config/2,
    connector_action_config_to_bridge_v1_config/3,
    bridge_v1_config_to_connector_config/2,
    has_custom_bridge_v1_config_to_connector_config/1,
    bridge_v1_config_to_action_config/3,
    has_custom_bridge_v1_config_to_action_config/1,
    transform_bridge_v1_config_to_action_config/4,
    action_convert_from_connector/3
]).
-export([clean_cache/0]).

-callback bridge_v1_type_name() ->
    atom()
    | {
        fun(({ActionConfig :: map(), ConnectorConfig :: map()}) -> Type :: atom()),
        TypeList :: [atom()]
    }.
-callback action_type_name() -> atom().
-callback connector_type_name() -> atom().
-callback schema_module() -> atom().
%% Define this if the automatic config downgrade is not enough for the bridge.
-callback connector_action_config_to_bridge_v1_config(
    ConnectorConfig :: map(), ActionConfig :: map()
) -> map().
%% Define this if the automatic config upgrade is not enough for the connector.
-callback bridge_v1_config_to_connector_config(BridgeV1Config :: map()) ->
    map() | {ConnectorTypeName :: atom(), map()}.
%% Define this if the automatic config upgrade is not enough for the bridge.
%% If you want to make use of the automatic config upgrade, you can call
%% emqx_action_info:transform_bridge_v1_config_to_action_config/4 in your
%% implementation and do some adjustments on the result.
-callback bridge_v1_config_to_action_config(BridgeV1Config :: map(), ConnectorName :: binary()) ->
    map() | {source | action, ActionTypeName :: atom(), map()} | 'none'.
-callback is_source() ->
    boolean().
-callback is_action() ->
    boolean().

-optional_callbacks([
    bridge_v1_type_name/0,
    connector_action_config_to_bridge_v1_config/2,
    bridge_v1_config_to_connector_config/1,
    bridge_v1_config_to_action_config/2,
    is_source/0,
    is_action/0
]).

%% ====================================================================
%% HardCoded list of info modules for actions
%% TODO: Remove this list once we have made sure that all relevants
%% apps are loaded before this module is called.
%% ====================================================================

-if(?EMQX_RELEASE_EDITION == ee).
hard_coded_action_info_modules_ee() ->
    [
        emqx_bridge_azure_event_hub_action_info,
        emqx_bridge_confluent_producer_action_info,
        emqx_bridge_dynamo_action_info,
        emqx_bridge_gcp_pubsub_consumer_action_info,
        emqx_bridge_gcp_pubsub_producer_action_info,
        emqx_bridge_kafka_action_info,
        emqx_bridge_kafka_consumer_action_info,
        emqx_bridge_kinesis_action_info,
        emqx_bridge_hstreamdb_action_info,
        emqx_bridge_matrix_action_info,
        emqx_bridge_mongodb_action_info,
        emqx_bridge_oracle_action_info,
        emqx_bridge_rocketmq_action_info,
        emqx_bridge_influxdb_action_info,
        emqx_bridge_cassandra_action_info,
        emqx_bridge_clickhouse_action_info,
        emqx_bridge_mysql_action_info,
        emqx_bridge_pgsql_action_info,
        emqx_bridge_syskeeper_action_info,
        emqx_bridge_sqlserver_action_info,
        emqx_bridge_timescale_action_info,
        emqx_bridge_redis_action_info,
        emqx_bridge_iotdb_action_info,
        emqx_bridge_es_action_info,
        emqx_bridge_opents_action_info,
        emqx_bridge_rabbitmq_action_info,
        emqx_bridge_pulsar_action_info,
        emqx_bridge_greptimedb_action_info,
        emqx_bridge_tdengine_action_info,
        emqx_bridge_s3_action_info
    ].
-else.
hard_coded_action_info_modules_ee() ->
    [].
-endif.

hard_coded_action_info_modules_common() ->
    [
        emqx_bridge_http_action_info,
        emqx_bridge_mqtt_pubsub_action_info
    ].

hard_coded_action_info_modules() ->
    hard_coded_action_info_modules_common() ++ hard_coded_action_info_modules_ee().

%% ====================================================================
%% API
%% ====================================================================

action_type_to_connector_type(Type) when not is_atom(Type) ->
    action_type_to_connector_type(binary_to_existing_atom(iolist_to_binary(Type)));
action_type_to_connector_type(Type) ->
    ActionInfoMap = info_map(),
    ActionTypeToConnectorTypeMap = maps:get(action_type_to_connector_type, ActionInfoMap),
    case maps:get(Type, ActionTypeToConnectorTypeMap, undefined) of
        undefined -> Type;
        ConnectorType -> ConnectorType
    end.

bridge_v1_type_to_action_type(Bin) when is_binary(Bin) ->
    bridge_v1_type_to_action_type(binary_to_existing_atom(Bin));
bridge_v1_type_to_action_type(Type) ->
    ActionInfoMap = info_map(),
    BridgeV1TypeToActionType = maps:get(bridge_v1_type_to_action_type, ActionInfoMap),
    case maps:get(Type, BridgeV1TypeToActionType, undefined) of
        undefined -> Type;
        ActionType -> ActionType
    end.

action_type_to_bridge_v1_type(Bin, Conf) when is_binary(Bin) ->
    action_type_to_bridge_v1_type(binary_to_existing_atom(Bin), Conf);
action_type_to_bridge_v1_type(ActionType, ActionConf) ->
    ActionInfoMap = info_map(),
    ActionTypeToBridgeV1Type = maps:get(action_type_to_bridge_v1_type, ActionInfoMap),
    case maps:get(ActionType, ActionTypeToBridgeV1Type, undefined) of
        undefined ->
            ActionType;
        BridgeV1TypeFun when is_function(BridgeV1TypeFun) ->
            case get_confs(ActionType, ActionConf) of
                {ConnectorConfig, ActionConfig} -> BridgeV1TypeFun({ConnectorConfig, ActionConfig});
                undefined -> ActionType
            end;
        BridgeV1Type ->
            BridgeV1Type
    end.

get_confs(ActionType, #{<<"connector">> := ConnectorName} = ActionConfig) ->
    ConnectorType = action_type_to_connector_type(ActionType),
    case emqx_conf:get_raw([connectors, ConnectorType, ConnectorName], undefined) of
        undefined -> undefined;
        ConnectorConfig -> {ConnectorConfig, ActionConfig}
    end;
get_confs(_, _) ->
    undefined.

%% We need this hack because of the bugs introduced by associating v2/action/source types
%% with v1 types unconditionally, like `mongodb' being a "valid" V1 bridge type, or
%% `confluent_producer', which has no v1 equivalent....
bridge_v1_type_name(ActionTypeBin) when is_binary(ActionTypeBin) ->
    bridge_v1_type_name(binary_to_existing_atom(ActionTypeBin));
bridge_v1_type_name(ActionType) ->
    Module = get_action_info_module(ActionType),
    case erlang:function_exported(Module, bridge_v1_type_name, 0) of
        true ->
            {ok, Module:bridge_v1_type_name()};
        false ->
            {error, no_v1_equivalent}
    end.

%% This function should return true for all inputs that are bridge V1 types for
%% bridges that have been refactored to bridge V2s, and for all all bridge V2
%% types. For everything else the function should return false.
is_action_type(Bin) when is_binary(Bin) ->
    is_action_type(binary_to_existing_atom(Bin));
is_action_type(Type) ->
    ActionInfoMap = info_map(),
    ActionTypes = maps:get(action_type_names, ActionInfoMap),
    case maps:get(Type, ActionTypes, undefined) of
        undefined -> false;
        _ -> true
    end.

%% Returns true if the action is an ingress action, false otherwise.
is_source(Bin) when is_binary(Bin) ->
    is_source(binary_to_existing_atom(Bin));
is_source(Type) ->
    ActionInfoMap = info_map(),
    IsSourceMap = maps:get(is_source, ActionInfoMap),
    maps:get(Type, IsSourceMap, false).

%% Returns true if the action is an egress action, false otherwise.
is_action(Bin) when is_binary(Bin) ->
    is_action(binary_to_existing_atom(Bin));
is_action(Type) ->
    ActionInfoMap = info_map(),
    IsActionMap = maps:get(is_action, ActionInfoMap),
    maps:get(Type, IsActionMap, true).

registered_schema_modules_actions() ->
    InfoMap = info_map(),
    Schemas = maps:get(action_type_to_schema_module, InfoMap),
    All = maps:to_list(Schemas),
    [{Type, SchemaMod} || {Type, SchemaMod} <- All, is_action(Type)].

registered_schema_modules_sources() ->
    InfoMap = info_map(),
    Schemas = maps:get(action_type_to_schema_module, InfoMap),
    All = maps:to_list(Schemas),
    [{Type, SchemaMod} || {Type, SchemaMod} <- All, is_source(Type)].

connector_action_config_to_bridge_v1_config(ActionOrBridgeType, ConnectorConfig, ActionConfig) ->
    Module = get_action_info_module(ActionOrBridgeType),
    case erlang:function_exported(Module, connector_action_config_to_bridge_v1_config, 2) of
        true ->
            Module:connector_action_config_to_bridge_v1_config(ConnectorConfig, ActionConfig);
        false ->
            connector_action_config_to_bridge_v1_config(ConnectorConfig, ActionConfig)
    end.

action_convert_from_connector(ActionOrBridgeType, ConnectorConfig, ActionConfig) ->
    Module = get_action_info_module(ActionOrBridgeType),
    case erlang:function_exported(Module, action_convert_from_connector, 2) of
        true ->
            Module:action_convert_from_connector(ConnectorConfig, ActionConfig);
        false ->
            ActionConfig
    end.

connector_action_config_to_bridge_v1_config(ConnectorConfig, ActionConfig) ->
    Merged = emqx_utils_maps:deep_merge(
        maps:without(
            [<<"connector">>],
            emqx_utils_maps:unindent(<<"parameters">>, ActionConfig)
        ),
        emqx_utils_maps:unindent(<<"parameters">>, ConnectorConfig)
    ),
    maps:without([<<"description">>], Merged).

has_custom_bridge_v1_config_to_connector_config(ActionOrBridgeType) ->
    Module = get_action_info_module(ActionOrBridgeType),
    erlang:function_exported(Module, bridge_v1_config_to_connector_config, 1).

bridge_v1_config_to_connector_config(ActionOrBridgeType, BridgeV1Config) ->
    Module = get_action_info_module(ActionOrBridgeType),
    %% should only be called if defined
    Module:bridge_v1_config_to_connector_config(BridgeV1Config).

has_custom_bridge_v1_config_to_action_config(ActionOrBridgeType) ->
    Module = get_action_info_module(ActionOrBridgeType),
    erlang:function_exported(Module, bridge_v1_config_to_action_config, 2).

bridge_v1_config_to_action_config(ActionOrBridgeType, BridgeV1Config, ConnectorName) ->
    Module = get_action_info_module(ActionOrBridgeType),
    %% should only be called if defined
    Module:bridge_v1_config_to_action_config(BridgeV1Config, ConnectorName).

transform_bridge_v1_config_to_action_config(
    BridgeV1Conf, ConnectorName, ConnectorConfSchemaMod, ConnectorConfSchemaName
) ->
    emqx_connector_schema:transform_bridge_v1_config_to_action_config(
        BridgeV1Conf, ConnectorName, ConnectorConfSchemaMod, ConnectorConfSchemaName
    ).

%% ====================================================================
%% Internal functions for building the info map and accessing it
%% ====================================================================

get_action_info_module(ActionOrBridgeType) ->
    InfoMap = info_map(),
    ActionInfoModuleMap = maps:get(action_type_to_info_module, InfoMap),
    maps:get(ActionOrBridgeType, ActionInfoModuleMap, undefined).

internal_emqx_action_persistent_term_info_key() ->
    ?FUNCTION_NAME.

info_map() ->
    case persistent_term:get(internal_emqx_action_persistent_term_info_key(), not_found) of
        not_found ->
            build_cache();
        ActionInfoMap ->
            ActionInfoMap
    end.

build_cache() ->
    ActionInfoModules = action_info_modules(),
    ActionInfoMap =
        lists:foldl(
            fun(Module, InfoMapSoFar) ->
                ModuleInfoMap = get_info_map(Module),
                emqx_utils_maps:deep_merge(InfoMapSoFar, ModuleInfoMap)
            end,
            initial_info_map(),
            ActionInfoModules
        ),
    %% Update the persistent term with the new info map
    persistent_term:put(internal_emqx_action_persistent_term_info_key(), ActionInfoMap),
    ActionInfoMap.

clean_cache() ->
    persistent_term:erase(internal_emqx_action_persistent_term_info_key()).

action_info_modules() ->
    ActionInfoModules = [
        action_info_modules(App)
     || {App, _, _} <- application:loaded_applications()
    ],
    lists:usort(lists:flatten(ActionInfoModules) ++ hard_coded_action_info_modules()).

action_info_modules(App) ->
    case application:get_env(App, emqx_action_info_modules) of
        {ok, Modules} ->
            Modules;
        _ ->
            []
    end.

initial_info_map() ->
    #{
        action_type_names => #{},
        bridge_v1_type_to_action_type => #{},
        action_type_to_bridge_v1_type => #{},
        action_type_to_connector_type => #{},
        action_type_to_schema_module => #{},
        action_type_to_info_module => #{},
        is_source => #{},
        is_action => #{}
    }.

get_info_map(Module) ->
    %% Force the module to get loaded
    _ = code:ensure_loaded(Module),
    ActionType = Module:action_type_name(),
    {BridgeV1TypeOrFun, BridgeV1Types} =
        case erlang:function_exported(Module, bridge_v1_type_name, 0) of
            true ->
                case Module:bridge_v1_type_name() of
                    {_BridgeV1TypeFun, _BridgeV1Types} = BridgeV1TypeTuple ->
                        BridgeV1TypeTuple;
                    BridgeV1Type0 ->
                        {BridgeV1Type0, [BridgeV1Type0]}
                end;
            false ->
                {ActionType, [ActionType]}
        end,
    IsIngress =
        case erlang:function_exported(Module, is_source, 0) of
            true ->
                Module:is_source();
            false ->
                false
        end,
    IsEgress =
        case erlang:function_exported(Module, is_action, 0) of
            true ->
                Module:is_action();
            false ->
                true
        end,
    #{
        action_type_names =>
            lists:foldl(
                fun(BridgeV1Type, M) ->
                    M#{BridgeV1Type => true}
                end,
                #{ActionType => true},
                BridgeV1Types
            ),
        bridge_v1_type_to_action_type =>
            lists:foldl(
                fun(BridgeV1Type, M) ->
                    %% Alias the bridge V1 type to the action type
                    M#{BridgeV1Type => ActionType}
                end,
                #{ActionType => ActionType},
                BridgeV1Types
            ),
        action_type_to_bridge_v1_type => #{
            ActionType => BridgeV1TypeOrFun
        },
        action_type_to_connector_type =>
            lists:foldl(
                fun(BridgeV1Type, M) ->
                    M#{BridgeV1Type => Module:connector_type_name()}
                end,
                #{ActionType => Module:connector_type_name()},
                BridgeV1Types
            ),
        action_type_to_schema_module => #{
            ActionType => Module:schema_module()
        },
        action_type_to_info_module =>
            lists:foldl(
                fun(BridgeV1Type, M) ->
                    M#{BridgeV1Type => Module}
                end,
                #{ActionType => Module},
                BridgeV1Types
            ),
        is_source => #{
            ActionType => IsIngress
        },
        is_action => #{
            ActionType => IsEgress
        }
    }.