drop function if exists get_referers(param_user_id bigint, param_user_bm_id smallint) cascade;
create function get_referers(param_user_id bigint, param_user_bm_id smallint) 
returns table  (
        referer_id bigint,
        referer_level integer
)  
as $end$
	declare
		origin_referer_id bigint;
		origin_level integer;
	begin
        SELECT user_bms.user_id, COUNT(*) % 5 + 1 
        FROM users, user_bms 
        WHERE 
            users.user_id=param_user_bm_id
        AND 
            user_bms.user_id=users.referer_id
        AND 
            user_bms.bm_id=param_user_bm_id
        GROUP BY user_bms.user_id
        INTO origin_referer_id, origin_level;

--        SELECT users.referer_id 
--        FROM users 
--        WHERE users.user_id = param_user_id 
--        INTO origin_referer_id;
-- 
--        SELECT COUNT(*) % 5 + 1 
--        FROM user_bms 
--        WHERE 
--            user_bms.user_id=origin_referer_id
--        AND 
--            user_bms.bm_id=param_user_bm_id
--        INTO origin_level;
--    
		return query with recursive tree as (
			select origin_referer_id as referer_id, origin_level as referer_level  
			
			union
			
			select 
				users.referer_id as referer_id, 
				tree.referer_level::integer - case when user_bms.user_id is null then 0 else 1 end as referer_level
		    from users
		    left join user_bms  
		    	on user_bms.user_id = users.user_id and user_bms.bm_id = param_user_bm_id
		    join tree
		        on tree.referer_id = users.user_id  and users.user_id != users.referer_id
		    where 
		    	tree.referer_level - case when user_bms.user_id is null then 0 else 1 end >= 0
			)
			select tree.referer_id, origin_level from tree order by tree.referer_level limit 1;
    end;
$end$ 
language plpgsql;


select * from get_referers(1122::bigint, 1::smallint);