%%%-------------------------------------------------------------------
%%% @author anlicheng
%%% @copyright (C) 2025, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 09. 5月 2025 16:45
%%%-------------------------------------------------------------------
-module(docker_deploy_log).
-author("anlicheng").

-behaviour(gen_server).

%% API
-export([start_link/0]).
-export([stash/2, flush/1, get_logs/1]).

%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).

-define(SERVER, ?MODULE).

-record(state, {
    %% #{task_id => queue:new()}
    pending_map = #{}
}).

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

-spec stash(TaskId :: integer(), Items :: binary() | [binary()]) -> no_return().
stash(TaskId, Log) when is_integer(TaskId), is_binary(Log) ->
    stash(TaskId, [Log]);
stash(TaskId, Items) when is_integer(TaskId), is_list(Items) ->
    {{Y, M, D}, {H, I, S}} = calendar:local_time(),
    TimePrefix = iolist_to_binary(io_lib:format("[~b-~2..0b-~2..0b ~2..0b:~2..0b:~2..0b]", [Y, M, D, H, I, S])),
    Log = iolist_to_binary([TimePrefix, <<" ">>, lists:join(<<" ">>, Items)]),
    gen_server:cast(?SERVER, {stash, TaskId, Log}).

-spec flush(TaskId :: integer()) -> no_return().
flush(TaskId) when is_integer(TaskId) ->
    gen_server:cast(?SERVER, {flush, TaskId}).

-spec get_logs(TaskId :: integer()) -> {ok, Logs :: list()}.
get_logs(TaskId) when is_integer(TaskId) ->
    gen_server:call(?SERVER, {get_logs, TaskId}).

%% @doc Spawns the server and registers the local name (unique)
-spec(start_link() ->
    {ok, Pid :: pid()} | ignore | {error, Reason :: term()}).
start_link() ->
    gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).

%%%===================================================================
%%% gen_server callbacks
%%%===================================================================

%% @private
%% @doc Initializes the server
-spec(init(Args :: term()) ->
    {ok, State :: #state{}} | {ok, State :: #state{}, timeout() | hibernate} |
    {stop, Reason :: term()} | ignore).
init([]) ->
    {ok, #state{}}.

%% @private
%% @doc Handling call messages
-spec(handle_call(Request :: term(), From :: {pid(), Tag :: term()},
    State :: #state{}) ->
    {reply, Reply :: term(), NewState :: #state{}} |
    {reply, Reply :: term(), NewState :: #state{}, timeout() | hibernate} |
    {noreply, NewState :: #state{}} |
    {noreply, NewState :: #state{}, timeout() | hibernate} |
    {stop, Reason :: term(), Reply :: term(), NewState :: #state{}} |
    {stop, Reason :: term(), NewState :: #state{}}).
handle_call({get_logs, TaskId}, _From, State = #state{pending_map = PendingMap}) ->
    case maps:find(TaskId, PendingMap) of
        error ->
            Logs = task_log_model:get_logs(TaskId),
            {reply, {ok, Logs}, State};
        {ok, Q} ->
            Logs = queue:to_list(Q),
            {reply, {ok, Logs}, State}
    end.

%% @private
%% @doc Handling cast messages
-spec(handle_cast(Request :: term(), State :: #state{}) ->
    {noreply, NewState :: #state{}} |
    {noreply, NewState :: #state{}, timeout() | hibernate} |
    {stop, Reason :: term(), NewState :: #state{}}).
handle_cast({stash, TaskId, Log}, State = #state{pending_map = PendingMap}) ->
    Q = maps:get(TaskId, PendingMap, queue:new()),
    NQ = queue:in(Log, Q),
    {noreply, State#state{pending_map = maps:put(TaskId, NQ, PendingMap)}};
handle_cast({flush, TaskId}, State = #state{pending_map = PendingMap}) ->
    case maps:take(TaskId, PendingMap) of
        error ->
            {noreply, State};
        {Q, NPendingMap} ->
            Logs = queue:to_list(Q),
            ok = task_log_model:insert(TaskId, Logs),
            {noreply, State#state{pending_map = NPendingMap}}
    end.

%% @private
%% @doc Handling all non call/cast messages
-spec(handle_info(Info :: timeout() | term(), State :: #state{}) ->
    {noreply, NewState :: #state{}} |
    {noreply, NewState :: #state{}, timeout() | hibernate} |
    {stop, Reason :: term(), NewState :: #state{}}).
handle_info(_Info, State = #state{}) ->
    {noreply, State}.

%% @private
%% @doc This function is called by a gen_server when it is about to
%% terminate. It should be the opposite of Module:init/1 and do any
%% necessary cleaning up. When it returns, the gen_server terminates
%% with Reason. The return value is ignored.
-spec(terminate(Reason :: (normal | shutdown | {shutdown, term()} | term()),
    State :: #state{}) -> term()).
terminate(_Reason, _State = #state{}) ->
    ok.

%% @private
%% @doc Convert process state when code is changed
-spec(code_change(OldVsn :: term() | {down, term()}, State :: #state{},
    Extra :: term()) ->
    {ok, NewState :: #state{}} | {error, Reason :: term()}).
code_change(_OldVsn, State = #state{}, _Extra) ->
    {ok, State}.

%%%===================================================================
%%% Internal functions
%%%===================================================================