SQL & PL/SQL

Hello Everyone,
I need your help in the following query using connect by:

I have 2 tabels
Tabel_1

Department hierarchy

department_id parent_department_id has_manager
1 NULL X
2 1
3 1 X
4 2 X
5 4


tabel_2

emp_id department_id is_manager
1 1 X
2 1
3 1
4 2
5 2
6 4 X
7 4
8 4
9 3 X
10 5 X
now in my company the concept of direct employees is as follow:

my direct employees are: the employees in my department + only the manager in the department below me in the hierarchy.

if the department bellow me has no manager then also these employees in that department reports to me
then we check the lower department and so on untill we find a manger then this manager reports to me but his employees reports to him so they are not my direct employees

for the above example should be as follows

if i want to get the direct employees of emp_id= 1

then result is
2
3
4
5
6
9


Best regards
Ibrahim