%%%-------------------------------------------------------------------
%%% File    : mod_shared_roster_sql.erl
%%% Author  : Evgeny Khramtsov <ekhramtsov@process-one.net>
%%% Created : 14 Apr 2016 by Evgeny Khramtsov <ekhramtsov@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2018   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.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%----------------------------------------------------------------------

-module(mod_shared_roster_sql).

-compile([{parse_transform, ejabberd_sql_pt}]).

-behaviour(mod_shared_roster).

%% API
-export([init/2, list_groups/1, groups_with_opts/1, create_group/3,
	 delete_group/2, get_group_opts/2, set_group_opts/3,
	 get_user_groups/2, get_group_explicit_users/2,
	 get_user_displayed_groups/3, is_user_in_group/3,
	 add_user_to_group/3, remove_user_from_group/3, import/3,
	 export/1]).

-include("jid.hrl").
-include("mod_roster.hrl").
-include("mod_shared_roster.hrl").
-include("ejabberd_sql_pt.hrl").

%%%===================================================================
%%% API
%%%===================================================================
init(_Host, _Opts) ->
    ok.

list_groups(Host) ->
    case ejabberd_sql:sql_query(
	   Host,
           ?SQL("select @(name)s from sr_group where %(Host)H")) of
	{selected, Rs} -> [G || {G} <- Rs];
	_ -> []
    end.

groups_with_opts(Host) ->
    case ejabberd_sql:sql_query(
           Host,
           ?SQL("select @(name)s, @(opts)s from sr_group where %(Host)H"))
	of
      {selected, Rs} ->
	  [{G, mod_shared_roster:opts_to_binary(ejabberd_sql:decode_term(Opts))}
	   || {G, Opts} <- Rs];
      _ -> []
    end.

create_group(Host, Group, Opts) ->
    SOpts = misc:term_to_expr(Opts),
    F = fun () ->
		?SQL_UPSERT_T(
                   "sr_group",
                   ["!name=%(Group)s",
                    "!server_host=%(Host)s",
                    "opts=%(SOpts)s"])
	end,
    ejabberd_sql:sql_transaction(Host, F).

delete_group(Host, Group) ->
    F = fun () ->
		ejabberd_sql:sql_query_t(
                  ?SQL("delete from sr_group where name=%(Group)s and %(Host)H")),
		ejabberd_sql:sql_query_t(
                  ?SQL("delete from sr_user where grp=%(Group)s and %(Host)H"))
	end,
    case ejabberd_sql:sql_transaction(Host, F) of
        {atomic,{updated,_}} -> {atomic, ok};
        Res -> Res
    end.

get_group_opts(Host, Group) ->
    case catch ejabberd_sql:sql_query(
		 Host,
		 ?SQL("select @(opts)s from sr_group"
                      " where name=%(Group)s and %(Host)H")) of
	{selected, [{SOpts}]} ->
	    mod_shared_roster:opts_to_binary(ejabberd_sql:decode_term(SOpts));
	_ -> error
    end.

set_group_opts(Host, Group, Opts) ->
    SOpts = misc:term_to_expr(Opts),
    F = fun () ->
		?SQL_UPSERT_T(
                   "sr_group",
                   ["!name=%(Group)s",
                    "!server_host=%(Host)s",
                    "opts=%(SOpts)s"])
	end,
    ejabberd_sql:sql_transaction(Host, F).

get_user_groups(US, Host) ->
    SJID = make_jid_s(US),
    case catch ejabberd_sql:sql_query(
		 Host,
		 ?SQL("select @(grp)s from sr_user"
                      " where jid=%(SJID)s and %(Host)H")) of
	{selected, Rs} -> [G || {G} <- Rs];
	_ -> []
    end.

get_group_explicit_users(Host, Group) ->
    case catch ejabberd_sql:sql_query(
		 Host,
		 ?SQL("select @(jid)s from sr_user"
                      " where grp=%(Group)s and %(Host)H")) of
	{selected, Rs} ->
	    lists:map(
	      fun({JID}) ->
		      {U, S, _} = jid:tolower(jid:decode(JID)),
		      {U, S}
	      end, Rs);
	_ ->
	    []
    end.

get_user_displayed_groups(LUser, LServer, GroupsOpts) ->
    SJID = make_jid_s(LUser, LServer),
    case catch ejabberd_sql:sql_query(
		 LServer,
		 ?SQL("select @(grp)s from sr_user"
                      " where jid=%(SJID)s and %(LServer)H")) of
	{selected, Rs} ->
	    [{Group, proplists:get_value(Group, GroupsOpts, [])}
	     || {Group} <- Rs];
	_ -> []
    end.

is_user_in_group(US, Group, Host) ->
    SJID = make_jid_s(US),
    case catch ejabberd_sql:sql_query(
                 Host,
                 ?SQL("select @(jid)s from sr_user where jid=%(SJID)s"
                      " and %(Host)H and grp=%(Group)s")) of
	{selected, []} -> false;
	_ -> true
    end.

add_user_to_group(Host, US, Group) ->
    SJID = make_jid_s(US),
    ejabberd_sql:sql_query(
      Host,
      ?SQL_INSERT(
         "sr_user",
         ["jid=%(SJID)s",
          "server_host=%(Host)s",
          "grp=%(Group)s"])).

remove_user_from_group(Host, US, Group) ->
    SJID = make_jid_s(US),
    F = fun () ->
		ejabberd_sql:sql_query_t(
                  ?SQL("delete from sr_user where jid=%(SJID)s and %(Host)H"
                       " and grp=%(Group)s")),
		ok
	end,
    ejabberd_sql:sql_transaction(Host, F).

export(_Server) ->
    [{sr_group,
      fun(Host, #sr_group{group_host = {Group, LServer}, opts = Opts})
            when LServer == Host ->
              SOpts = misc:term_to_expr(Opts),
              [?SQL("delete from sr_group where name=%(Group)s and %(Host)H;"),
               ?SQL_INSERT(
                  "sr_group",
                  ["name=%(Group)s",
                   "server_host=%(Host)s",
                   "opts=%(SOpts)s"])];
         (_Host, _R) ->
              []
      end},
     {sr_user,
      fun(Host, #sr_user{us = {U, S}, group_host = {Group, LServer}})
            when LServer == Host ->
              SJID = make_jid_s(U, S),
              [?SQL("select @(jid)s from sr_user where jid=%(SJID)s"
                    " and %(Host)H and grp=%(Group)s;"),
               ?SQL_INSERT(
                  "sr_user",
                  ["jid=%(SJID)s",
                   "server_host=%(Host)s",
                   "grp=%(Group)s"])];
         (_Host, _R) ->
              []
      end}].

import(_, _, _) ->
    ok.

%%%===================================================================
%%% Internal functions
%%%===================================================================
make_jid_s(U, S) ->
    jid:encode(jid:tolower(jid:make(U, S))).

make_jid_s({U, S}) -> make_jid_s(U, S).
