= UC0003 Prototype Implementation - Approve or Reject Reservations =

'''Initiating actor:''' Faculty Administrator

'''Other actors:''' Teaching Staff, Student (the requesters)

The administrator views a list of all pending reservations, selects one to review in detail (including conflict analysis and recurrence information), and approves or rejects it.

== Scenario ==

 1. The administrator selects ''Approve or Reject Reservations'' from the main menu. The system queries all pending reservations:
{{{
SELECT res.reservation_id, res.start_time, res.end_time,
       res.purpose, res.created_at, res.recurrence_group_id, res.resource_id,
       u.first_name || ' ' || u.last_name AS requested_by,
       ut.type_name AS requester_role,
       r.name AS resource_name, l.building, l.room
FROM reservations res
JOIN users u ON res.user_id = u.user_id
JOIN user_types ut ON u.type_id = ut.type_id
JOIN resources r ON res.resource_id = r.resource_id
JOIN resource_types rt ON r.type_id = rt.type_id
LEFT JOIN locations l ON r.location_id = l.location_id
WHERE res.status = 'pending'
ORDER BY res.created_at ASC;
}}}

The system displays the pending reservations as a numbered list:
{{{
=== Pending Reservations (4) ===

  1. [#4] Database Systems Lecture - Week 4
       by Elena Stojanova (Teaching Staff)
       Lecture Hall 201 (FINKI-A / 201)
       2026-02-24 09:00 - 2026-02-24 11:00
  2. [#10] Thesis writing session
       by David Angelovski (Student)
       ...
}}}

 2. The administrator selects reservation #4 to review. The system shows full details and detects it is part of a recurring series.
{{{
SELECT reservation_id, start_time, end_time, status
FROM reservations
WHERE recurrence_group_id = 'a1b2c3d4-e5f6-4789-abcd-ef0123456789'
ORDER BY start_time;
}}}

 3. The system checks for conflicts with approved reservations on the same resource and time.
{{{
SELECT res2.reservation_id, res2.start_time, res2.end_time,
       res2.purpose
FROM reservations res2
WHERE res2.resource_id = 3
  AND res2.reservation_id != 4
  AND res2.status = 'approved'
  AND res2.start_time < '2026-02-24 11:00:00'
  AND res2.end_time > '2026-02-24 09:00:00';
}}}

 4. No conflicts found. The administrator approves the reservation. The system updates the status:
{{{
UPDATE reservations
SET status = 'approved', approved_by = 1
WHERE reservation_id = 4 AND status = 'pending'
RETURNING reservation_id, status;
}}}

The system confirms the action:
{{{
  Reservation #4 has been approved.
}}}