-module(mdns_client_lib).

-export([start/0,
         instance/1,
         call/2,
         call/3,
         stream/5,
         cast/2,
         sure_cast/2,
         servers/1
        ]).

-export_types([stream_fun/0]).

-type stream_fun() :: fun(({stream, term} | done, Acc) ->  Acc).
%%--------------------------------------------------------------------
%% @doc
%% Creates a new instance of a mdns client library, this should
%% be called with your service name to initialize a connection.
%% It can be called twice or more with different services to allow
%% talking to multiple endpoints.
%%
%% @spec instance(Service::string()) -> Pid::pid()
%% @end
%%--------------------------------------------------------------------

-spec instance(Service::string()) -> {'error', _} |
                                     {'ok', 'undefined' | pid()} |
                                     {'ok', 'undefined' | pid(), _}.
instance(Service) ->
    supervisor:start_child(mdns_client_lib_instance_sup, [Service]).


%%--------------------------------------------------------------------
%% @doc
%% Calls the client, if no servers are present it will return en
%% error. This call is syncronous. Not being connected has to be
%% handled by the library user.
%%
%% @spec call(Pid::pid(), Msg::term()) -> {ok, Reply::term()} |
%%                         {error, no_server}
%% @end
%%--------------------------------------------------------------------


-spec call(Pid::pid(), Msg::term()) ->
                  noreply |
                  pong |
                  {error, no_servers} |
                  {reply, Reply::term()}.
call(Pid, Msg) ->
    mdns_client_lib_server:call(Pid, Msg).

call(Pid, Msg, Timeout) ->
    mdns_client_lib_server:call(Pid, Msg, Timeout).


%%--------------------------------------------------------------------
%% @doc
%% Streams data from the client, for each chunk StreamFn is called.
%%
%% @end
%%--------------------------------------------------------------------

-spec stream(Pid::pid(), Msg::term(), StreamFn :: stream_fun(),
             Acc0 :: term(), Timeout :: pos_integer() | infinity) ->
                  noreply |
                  {error, no_servers} |
                  {reply, Reply::term()}.

stream(Pid, Msg, StreamFn, Acc0, Timeout) ->
    mdns_client_lib_server:stream(Pid, Msg, StreamFn, Acc0, Timeout).

%%--------------------------------------------------------------------
%% @doc
%% Sends a ansyncronous message to the server. This call is
%% assyncronous, all failures will be ignored, it's simple fire and
%% forget.
%%
%% @spec cast(Pid::pid(), Msg::term()) -> ok
%%
%% @end
%%--------------------------------------------------------------------

-spec cast(Pid::pid(), Msg::term()) -> ok.
cast(Pid, Msg) ->
    mdns_client_lib_server:cast(Pid, Msg).

%%--------------------------------------------------------------------
%% @doc
%% Sends a ansyncronous message to the server. This call is
%% assyncronous. Since it's not possible to know if there was a
%% successful send the library takes care of resending, order is
%% not guaranteed.
%%
%% @spec cast(Pid::pid(), Msg::term()) -> ok
%%
%% @end

-spec sure_cast(Pid::pid(), Msg::term()) -> ok.
sure_cast(Pid, Msg) ->
    mdns_client_lib_server:sure_cast(Pid, Msg).

%%--------------------------------------------------------------------
%% @doc
%% Lists all servers discovered by an isntance, this is mostly
%% informational.
%%
%% @spec servers(Pid::pid()) -> [Server::term()]
%% @end
%%--------------------------------------------------------------------

-spec servers(Pid::pid()) -> [Server::term()].
servers(Pid) ->
    mdns_client_lib_server:servers(Pid).

%%--------------------------------------------------------------------
%% @private
%% @doc
%% Starts the application.
%%
%% @spec start() -> any()
%% @end
%%--------------------------------------------------------------------

-spec start() -> any().
start() ->
    application:start(mdns_client_lib).