/**
	This file is a part of r0nk, atlas_moon, and rexy's matrix client
	Copyright (C) 2019 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 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 Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "matrix/syncer.hpp"
#include "raii/static_string.hpp"
#include "raii/rjp_ptr.hpp"
#include "raii/util.hpp"

namespace matrix{

	syncer::syncer(std::shared_ptr<internal::session_info>& ses):
		client_base(),
		m_ses(ses){}

	raii::string syncer::sync(size_t timeout){
		raii::string reply = _get_curl(m_ses->urls.sync(m_ses->homeserver, m_ses->access_token, m_next_batch, raii::itostr(timeout)));

		if(!reply)
			return {};
		raii::rjp_ptr root(rjp_parse(reply));
		if(!root)
			return reply;

		RJP_search_res res = rjp_search_member(root.get(), "next_batch", 0);
		if(!res.value)
			return reply;
		m_next_batch = res.value;

		if(m_raw_callback != nullptr){
			m_raw_callback(root);
		}
		res = rjp_search_member(root.get(), "rooms", 0);
		if(res.value){
			if(m_message_callback != nullptr)
				_handle_messages(res.value);
			if(m_membership_callback != nullptr)
				_handle_membership_events(res.value);
		}
		return reply;
	}


	static membership_info _membership_info_from_json(RJP_value* event, RJP_value* roomid){
		static constexpr const char* search_terms[] = {"event_id", "sender", "state_key", "unsigned", "type", "origin_server_ts"};
		static constexpr size_t num_searches = sizeof(search_terms)/sizeof(search_terms[0]);
		RJP_search_res results[num_searches] = {};
		rjp_search_members(event, num_searches, search_terms, results, 0);
		for(size_t i = 0;i < num_searches;++i){
			if(!results[i].value)
				return {};
		}
		RJP_search_res age = rjp_search_member(results[3].value, "age", 0);
		if(!age.value) return {};

		raii::rjp_string room_str = rjp_member_name(roomid);
		raii::rjp_string sender_str = results[1].value;
		raii::rjp_string event_str = results[0].value;
		raii::rjp_string eventtype_str = results[4].value;
		raii::rjp_string rec_str = results[2].value;

		return membership_info{std::move(room_str), std::move(sender_str),
		                       std::move(event_str), std::move(eventtype_str),
		                       rjp_value_integer(results[5].value), rjp_value_integer(age.value),
		                       std::move(rec_str)};
	}
	static msg_info _message_info_from_json(RJP_value* event, RJP_value* roomid){
		static constexpr const char* searches[] = {"sender", "content", "event_id", "unsigned", "type", "origin_server_ts"};
		static constexpr size_t num_searches = sizeof(searches)/sizeof(searches[0]);
		RJP_search_res results[num_searches] = {};
		rjp_search_members(event, num_searches, searches, results, 0);
		for(size_t i = 0;i < num_searches;++i){
			if(!results[i].value)
				return msg_info{};
		}
		RJP_search_res msg = rjp_search_member(results[1].value, "msgtype", 0);
		if(!msg.value) return {};
		RJP_search_res body = rjp_search_member(results[1].value, "body", 0);
		if(!body.value) return {};
		RJP_search_res age = rjp_search_member(results[3].value, "age", 0);
		if(!age.value) return msg_info{};
		raii::rjp_string room_str = rjp_member_name(roomid);
		raii::rjp_string sender_str = results[0].value;
		raii::rjp_string eventid_str = results[2].value;
		raii::rjp_string eventtype_str = results[3].value;
		raii::rjp_string msgbody_str = body.value;
		return msg_info{std::move(room_str), std::move(sender_str),
		                std::move(eventid_str), std::move(eventtype_str),
		                rjp_value_integer(results[5].value), rjp_value_integer(age.value),
		                msg::from_str(rjp_value_string(msg.value)), std::move(msgbody_str)};
	}
	void syncer::_handle_membership_events(RJP_value* rooms){
		RJP_search_res res = rjp_search_member(rooms, "invite", 0);
		if(res.value)
			_handle_invites(res.value);
		res = rjp_search_member(rooms, "join", 0);
		if(res.value)
			_handle_other_membership(res.value);
	}
	void syncer::_handle_other_membership(RJP_value* join){
		for(RJP_value* roomid = rjp_get_member(join);roomid;roomid = rjp_next_member(roomid)){
			RJP_search_res res = rjp_search_member(roomid, "timeline", 0);
			if(!res.value) continue;
			res = rjp_search_member(res.value, "events", 0);
			if(!res.value) continue;
			for(RJP_value* event = rjp_get_element(res.value);event;event = rjp_next_element(event)){
				membership_info minfo = _membership_info_from_json(event, roomid);
				if(!minfo.roomid) continue;
				if(minfo.eventtype != "m.room.member"_ss) continue;

				m_membership_callback(minfo);
			}
		}
	}
	void syncer::_handle_invites(RJP_value* invites){
		for(RJP_value* roomid = rjp_get_member(invites);roomid;roomid = rjp_next_member(roomid)){
			RJP_search_res res = rjp_search_member(roomid, "invite_state", 0);
			if(!res.value) continue;
			res = rjp_search_member(res.value, "events", 0);
			if(!res.value) continue;
			for(RJP_value* event = rjp_get_element(res.value);event;event = rjp_next_element(event)){
				membership_info minfo = _membership_info_from_json(event, roomid);
				if(!minfo.roomid) continue;
				m_membership_callback(minfo);
			}
		}
	}
	void syncer::_handle_messages(RJP_value* messages){
		RJP_search_res res = rjp_search_member(messages, "join", 0);
		if(!res.value) return;
		for(RJP_value* roomid = rjp_get_member(res.value);roomid;roomid = rjp_next_member(roomid)){
			res = rjp_search_member(roomid, "timeline", 0);
			if(!res.value) continue;
			res = rjp_search_member(res.value, "events", 0);
			if(!res.value) continue;
			for(RJP_value* event = rjp_get_element(res.value);event;event = rjp_next_element(event)){
				msg_info minfo = _message_info_from_json(event, roomid);
				m_message_callback(minfo);
			}
		}
	}
}