%% 
%% %CopyrightBegin%
%% 
%% Copyright Ericsson AB 2004-2009. 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.
%% 
%% %CopyrightEnd%
%% 

-module(snmpm_misc_sup).

-include("snmp_debug.hrl").

-behaviour(supervisor).

%% External exports
-export([
	 start_link/0, 
	 start_net_if/2, stop_net_if/0,
	 start_note_store/2, stop_note_store/0
	]).

%% Internal exports
-export([init/1]).

-define(SUP, ?MODULE).


%%%-----------------------------------------------------------------
%%% This is a supervisor for the mib and net_ifprocesses.
%%% Each agent has one mib process.
%%%-----------------------------------------------------------------

start_link() ->
    ?d("start_link -> entry", []),
    SupName = {local,?SUP},
    supervisor:start_link(SupName, ?MODULE, []).


start_net_if(Mod, NoteStore) ->
    ?d("start_net_if -> entry with"
       "~n   Mod:       ~p"
       "~n   NoteStore: ~p", [Mod, NoteStore]),
    SupName = ?SUP, 
    Name    = net_if, 
    Args    = [self(), NoteStore],
    start_sup_child(SupName, Name, Mod, Args).

stop_net_if() ->
    stop_sup_child(?SUP, net_if).


%% The note store is a common code component, so we must
%% pass all the arguments in a way that works both for
%% the agent and the manager entities. I.e. as arguments
%% to the start_link function.
start_note_store(Prio, Opts) ->
    ?d("start_note_store -> entry with"
       "~n   Prio: ~p"
       "~n   Opts: ~p", [Prio, Opts]),
    SupName = ?MODULE, 
    Name    = note_store, 
    Mod     = snmp_note_store, 
    Args    = [Prio, snmpm, Opts], 
    start_sup_child(SupName, Name, Mod, Args).

stop_note_store() ->
    stop_sup_child(?SUP, note_store).


%% ---------------------------------------------------------------

start_sup_child(SupName, Name, Mod, Args) ->
    %% make sure we start from scratch...
    Children = supervisor:which_children(SupName),
    case lists:keysearch(Name, 1, Children) of
	{value, {_, _Pid, _, _}} ->
	    stop_sup_child(SupName, Name);
	_ ->
	    ok
    end,
    Spec = {Name, 
	    {Mod, start_link, Args},
	    temporary, 2000, worker, [Mod]},
    supervisor:start_child(SupName, Spec).

stop_sup_child(SupName, Name) ->
    case whereis(SupName) of
	undefined ->
	    ok;
	_ ->
	    supervisor:terminate_child(SupName, Name),
	    supervisor:delete_child(SupName, Name)
    end.



init([]) ->
    ?d("init -> entry", []),
    SupFlags = {one_for_all, 0, 3600},
    {ok, {SupFlags, []}}.

