%%%----------------------------------------------------------------------
%%% File    : adhoc.erl
%%% Author  : Magnus Henoch <henoch@dtek.chalmers.se>
%%% Purpose : Provide helper functions for ad-hoc commands (JEP-0050)
%%% Created : 31 Oct 2005 by Magnus Henoch <henoch@dtek.chalmers.se>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2009   ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License
%%% along with this program; if not, write to the Free Software
%%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
%%% 02111-1307 USA
%%%
%%%----------------------------------------------------------------------

-module(adhoc).
-author('henoch@dtek.chalmers.se').

-export([parse_request/1,
	 produce_response/2,
	 produce_response/1]).

-include("ejabberd.hrl").
-include("jlib.hrl").
-include("adhoc.hrl").

%% Parse an ad-hoc request.  Return either an adhoc_request record or
%% an {error, ErrorType} tuple.
parse_request(#iq{type = set, lang = Lang, sub_el = SubEl, xmlns = ?NS_COMMANDS}) ->
    ?DEBUG("entering parse_request...", []),
    Node = xml:get_tag_attr_s("node", SubEl),
    SessionID = xml:get_tag_attr_s("sessionid", SubEl),
    Action = xml:get_tag_attr_s("action", SubEl),
    XData = find_xdata_el(SubEl),
    {xmlelement, _, _, AllEls} = SubEl,
    if XData ->
	    Others = lists:delete(XData, AllEls);
       true ->
	    Others = AllEls
    end,

    #adhoc_request{lang = Lang,
		   node = Node,
		   sessionid = SessionID,
		   action = Action,
		   xdata = XData,
		   others = Others};
parse_request(_) ->
    {error, ?ERR_BAD_REQUEST}.

%% Borrowed from mod_vcard.erl
find_xdata_el({xmlelement, _Name, _Attrs, SubEls}) ->
    find_xdata_el1(SubEls).

find_xdata_el1([]) ->
    false;
find_xdata_el1([{xmlelement, Name, Attrs, SubEls} | Els]) ->
    case xml:get_attr_s("xmlns", Attrs) of
	?NS_XDATA ->
	    {xmlelement, Name, Attrs, SubEls};
	_ ->
	    find_xdata_el1(Els)
    end;
find_xdata_el1([_ | Els]) ->
    find_xdata_el1(Els).

%% Produce a <command/> node to use as response from an adhoc_response
%% record, filling in values for language, node and session id from
%% the request.
produce_response(#adhoc_request{lang = Lang,
				node = Node,
				sessionid = SessionID},
		 Response) ->
    produce_response(Response#adhoc_response{lang = Lang,
					     node = Node,
					     sessionid = SessionID}).

%% Produce a <command/> node to use as response from an adhoc_response
%% record.
produce_response(#adhoc_response{lang = _Lang,
				 node = Node,
				 sessionid = ProvidedSessionID,
				 status = Status,
				 defaultaction = DefaultAction,
				 actions = Actions,
				 notes = Notes,
				 elements = Elements}) ->
    SessionID = if is_list(ProvidedSessionID), ProvidedSessionID /= "" ->
			ProvidedSessionID;
		   true ->
			jlib:now_to_utc_string(now())
		end,
    case Actions of
	[] ->
	    ActionsEls = [];
	_ ->
	    case DefaultAction of
		"" ->
		    ActionsElAttrs = [];
		_ ->
		    ActionsElAttrs = [{"execute", DefaultAction}]
	    end,
	    ActionsEls = [{xmlelement, "actions",
			   ActionsElAttrs,
			   [{xmlelement, Action, [], []} || Action <- Actions]}]
    end,
    NotesEls = lists:map(fun({Type, Text}) ->
				 {xmlelement, "note",
				  [{"type", Type}],
				  [{xmlcdata, Text}]}
			 end, Notes),
    {xmlelement, "command",
     [{"xmlns", ?NS_COMMANDS},
      {"sessionid", SessionID},
      {"node", Node},
      {"status", atom_to_list(Status)}],
     ActionsEls ++ NotesEls ++ Elements}.