-- Prosody IM

-- Copyright (C) 2008-2009 Matthew Wild

-- Copyright (C) 2008-2009 Waqas Hussain

-- 

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local datamanager = require "util.datamanager";

local datetime = require "util.datetime";

local jid_split = require "util.jid".split;

local jid_bare = require "util.jid".bare;

local st = require "util.stanza";

local log = require "util.logger".init("mod_muc");

local multitable_new = require "util.multitable".new;

local t_insert, t_remove = table.insert, table.remove;

local setmetatable = setmetatable;

local muc_domain = nil; --module:get_host();

local history_length = 20;

------------

local function filter_xmlns_from_array(array, filters)

	local count = 0;

	for i=#array,1,-1 do

		local attr = array[i].attr;

		if filters[attr and attr.xmlns] then

			t_remove(array, i);

			count = count + 1;

		end

	end

	return count;

end

local function filter_xmlns_from_stanza(stanza, filters)

	if filters then

		if filter_xmlns_from_array(stanza.tags, filters) ~= 0 then

			return stanza, filter_xmlns_from_array(stanza, filters);

		end

	end

	return stanza, 0;

end

local presence_filters = {["http://jabber.org/protocol/muc"]=true;["http://jabber.org/protocol/muc#user"]=true};

local function get_filtered_presence(stanza)

	return filter_xmlns_from_stanza(st.clone(stanza), presence_filters);

end

local kickable_error_conditions = {

	["gone"] = true;

	["internal-server-error"] = true;

	["item-not-found"] = true;

	["jid-malformed"] = true;

	["recipient-unavailable"] = true;

	["redirect"] = true;

	["remote-server-not-found"] = true;

	["remote-server-timeout"] = true;

	["service-unavailable"] = true;

};

local function get_kickable_error(stanza)

	for _, tag in ipairs(stanza.tags) do

		if tag.name == "error" and tag.attr.xmlns == "jabber:client" then

			for _, cond in ipairs(tag.tags) do

				if cond.attr.xmlns == "urn:ietf:params:xml:ns:xmpp-stanzas" then

					return kickable_error_conditions[cond.name] and cond.name;

				end

			end

			return true; -- malformed error message

		end

	end

	return true; -- malformed error message

end

local function getUsingPath(stanza, path, getText)

	local tag = stanza;

	for _, name in ipairs(path) do

		if type(tag) ~= 'table' then return; end

		tag = tag:child_with_name(name);

	end

	if tag and getText then tag = table.concat(tag); end

	return tag;

end

local function getTag(stanza, path) return getUsingPath(stanza, path); end

local function getText(stanza, path) return getUsingPath(stanza, path, true); end

-----------

--[[function get_room_disco_info(room, stanza)

	return st.iq({type='result', id=stanza.attr.id, from=stanza.attr.to, to=stanza.attr.from}):query("http://jabber.org/protocol/disco#info")

		:tag("identity", {category='conference', type='text', name=room._data["name"]):up()

		:tag("feature", {var="http://jabber.org/protocol/muc"}); -- TODO cache disco reply

end

function get_room_disco_items(room, stanza)

	return st.iq({type='result', id=stanza.attr.id, from=stanza.attr.to, to=stanza.attr.from}):query("http://jabber.org/protocol/disco#items");

end -- TODO allow non-private rooms]]

--

local room_mt = {};

room_mt.__index = room_mt;

function room_mt:get_default_role(affiliation)

	if affiliation == "owner" or affiliation == "admin" then

		return "moderator";

	elseif affiliation == "member" or not affiliation then

		return "participant";

	end

end

function room_mt:broadcast_presence(stanza, code, nick)

	stanza = get_filtered_presence(stanza);

	local data = self._occupants[stanza.attr.from];

	stanza:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})

		:tag("item", {affiliation=data.affiliation, role=data.role, nick=nick}):up();

	if code then

		stanza:tag("status", {code=code}):up();

	end

	local me;

	for occupant, o_data in pairs(self._occupants) do

		if occupant ~= stanza.attr.from then

			for jid in pairs(o_data.sessions) do

				stanza.attr.to = jid;

				self:route_stanza(stanza);

			end

		else

			me = o_data;

		end

	end

	if me then

		stanza:tag("status", {code='110'});

		for jid in pairs(me.sessions) do

			stanza.attr.to = jid;

			self:route_stanza(stanza);

		end

	end

end

function room_mt:broadcast_message(stanza, historic)

	for occupant, o_data in pairs(self._occupants) do

		for jid in pairs(o_data.sessions) do

			stanza.attr.to = jid;

			self:route_stanza(stanza);

		end

	end

	if historic then -- add to history

		local history = self._data['history'];

		if not history then history = {}; self._data['history'] = history; end

		-- stanza = st.clone(stanza);

		stanza:tag("delay", {xmlns = "urn:xmpp:delay", from = muc_domain, stamp = datetime.datetime()}):up(); -- XEP-0203

		stanza:tag("x", {xmlns = "jabber:x:delay", from = muc_domain, stamp = datetime.legacy()}):up(); -- XEP-0091 (deprecated)

		t_insert(history, st.clone(st.preserialize(stanza)));

		while #history > history_length do t_remove(history, 1) end

	end

end

function room_mt:broadcast_except_nick(stanza, nick)

	for rnick, occupant in pairs(self._occupants) do

		if rnick ~= nick then

			for jid in pairs(occupant.sessions) do

				stanza.attr.to = jid;

				self:route_stanza(stanza);

			end

		end

	end

end

function room_mt:send_occupant_list(to)

	local current_nick = self._jid_nick[to];

	for occupant, o_data in pairs(self._occupants) do

		if occupant ~= current_nick then

			local pres = get_filtered_presence(o_data.sessions[o_data.jid]);

			pres.attr.to, pres.attr.from = to, occupant;

			pres:tag("x", {xmlns='http://jabber.org/protocol/muc#user'})

				:tag("item", {affiliation=o_data.affiliation, role=o_data.role}):up();

			self:route_stanza(pres);

		end

	end

end

function room_mt:send_history(to)

	local history = self._data['history']; -- send discussion history

	if history then

		for _, msg in ipairs(history) do

			msg = st.deserialize(msg);

			msg.attr.to=to;

			self:route_stanza(msg);

		end

	end

	if self._data['subject'] then

		self:route_stanza(st.message({type='groupchat', from=self.jid, to=to}):tag("subject"):text(self._data['subject']));

	end

end

local function room_get_disco_info(self, stanza)

	return st.reply(stanza):query("http://jabber.org/protocol/disco#info"):tag("identity", {category="conference", type="text"});

end

local function room_get_disco_items(self, stanza)

	return st.reply(stanza):query("http://jabber.org/protocol/disco#items");

end

function room_mt:set_subject(current_nick, subject)

	-- TODO check nick's authority

	if subject == "" then subject = nil; end

	self._data['subject'] = subject;

	if self.save then self:save(); end

	local msg = st.message({type='groupchat', from=current_nick})

		:tag('subject'):text(subject):up();

	self:broadcast_message(msg, false);

	return true;

end

function room_mt:handle_to_occupant(origin, stanza) -- PM, vCards, etc

	local from, to = stanza.attr.from, stanza.attr.to;

	local room = jid_bare(to);

	local current_nick = self._jid_nick[from];

	local type = stanza.attr.type;

	log("debug", "room: %s, current_nick: %s, stanza: %s", room or "nil", current_nick or "nil", stanza:top_tag());

	if (select(2, jid_split(from)) == muc_domain) then error("Presence from the MUC itself!!!"); end

	if stanza.name == "presence" then

		local pr = get_filtered_presence(stanza);

		pr.attr.from = current_nick;

		if type == "error" then -- error, kick em out!

			if current_nick then

				log("debug", "kicking %s from %s", current_nick, room);

				self:handle_to_occupant(origin, st.presence({type='unavailable', from=from, to=to})

					:tag('status'):text('This participant is kicked from the room because he sent an error presence')); -- send unavailable

			end

		elseif type == "unavailable" then -- unavailable

			if current_nick then

				log("debug", "%s leaving %s", current_nick, room);

				local data = self._occupants[current_nick];

				data.role = 'none';

				self:broadcast_presence(pr);

				self._occupants[current_nick] = nil;

				self._jid_nick[from] = nil;

			end

		elseif not type then -- available

			if current_nick then

				--if #pr == #stanza or current_nick ~= to then -- commented because google keeps resending directed presence

					if current_nick == to then -- simple presence

						log("debug", "%s broadcasted presence", current_nick);

						self._occupants[current_nick].sessions[from] = pr;

						self:broadcast_presence(pr);

					else -- change nick

						if self._occupants[to] then

							log("debug", "%s couldn't change nick", current_nick);

							origin.send(st.error_reply(stanza, "cancel", "conflict"):tag("x", {xmlns = "http://jabber.org/protocol/muc"}));

						else

							local data = self._occupants[current_nick];

							local to_nick = select(3, jid_split(to));

							if to_nick then

								log("debug", "%s (%s) changing nick to %s", current_nick, data.jid, to);

								local p = st.presence({type='unavailable', from=current_nick});

								self:broadcast_presence(p, '303', to_nick);

								self._occupants[current_nick] = nil;

								self._occupants[to] = data;

								self._jid_nick[from] = to;

								pr.attr.from = to;

								self._occupants[to].sessions[from] = pr;

								self:broadcast_presence(pr);

							else

								--TODO malformed-jid

							end

						end

					end

				--else -- possible rejoin

				--	log("debug", "%s had connection replaced", current_nick);

				--	self:handle_to_occupant(origin, st.presence({type='unavailable', from=from, to=to})

				--		:tag('status'):text('Replaced by new connection'):up()); -- send unavailable

				--	self:handle_to_occupant(origin, stanza); -- resend available

				--end

			else -- enter room

				local new_nick = to;

				if self._occupants[to] then

					new_nick = nil;

				end

				if not new_nick then

					log("debug", "%s couldn't join due to nick conflict: %s", from, to);

					origin.send(st.error_reply(stanza, "cancel", "conflict"):tag("x", {xmlns = "http://jabber.org/protocol/muc"}));

				else

					log("debug", "%s joining as %s", from, to);

					if not next(self._affiliations) then -- new room, no owners

						self._affiliations[jid_bare(from)] = "owner";

					end

					local affiliation = self:get_affiliation(from);

					local role = self:get_default_role(affiliation)

					if role then -- new occupant

						self._occupants[to] = {affiliation=affiliation, role=role, jid=from, sessions={[from]=get_filtered_presence(stanza)}};

						self._jid_nick[from] = to;

						self:send_occupant_list(from);

						pr.attr.from = to;

						self:broadcast_presence(pr);

						self:send_history(from);

					else -- banned

						origin.send(st.error_reply(stanza, "auth", "forbidden"):tag("x", {xmlns = "http://jabber.org/protocol/muc"}));

					end

				end

			end

		elseif type ~= 'result' then -- bad type

			origin.send(st.error_reply(stanza, "modify", "bad-request")); -- FIXME correct error?

		end

	elseif stanza.name == "message" and type == "groupchat" then -- groupchat messages not allowed in PM

		origin.send(st.error_reply(stanza, "modify", "bad-request"));

	else -- private stanza

		local o_data = self._occupants[to];

		if o_data then

			log("debug", "%s sent private stanza to %s (%s)", from, to, o_data.jid);

			local jid = o_data.jid;

			stanza.attr.to, stanza.attr.from = jid, current_nick;

			self:route_stanza(stanza);

		elseif type ~= "error" and type ~= "result" then -- recipient not in room

			origin.send(st.error_reply(stanza, "cancel", "item-not-found", "Recipient not in room"));

		end

	end

end

function room_mt:handle_form(origin, stanza)

	if self:get_affiliation(stanza.attr.from) ~= "owner" then origin.send(st.error_reply(stanza, "auth", "forbidden")); return; end

	if stanza.attr.type == "get" then

		local title = "Configuration for "..self.jid;

		origin.send(st.reply(stanza):query("http://jabber.org/protocol/muc#owner")

			:tag("x", {xmlns='jabber:x:data', type='form'})

				:tag("title"):text(title):up()

				:tag("instructions"):text(title):up()

				:tag("field", {type='hidden', var='FORM_TYPE'}):tag("value"):text("http://jabber.org/protocol/muc#roomconfig"):up():up()

				:tag("field", {type='boolean', label='Make Room Persistent?', var='muc#roomconfig_persistentroom'})

					:tag("value"):text(self._data.persistent and "1" or "0"):up()