Domain Rules

Bookings

• A booking is (desk, date, employee) and covers the whole day.
• A desk can have at most one booking per day.
• An employee can hold at most one booking per day.
• Bookings are allowed from today up to 14 days ahead. Past dates are rejected.
• Only cells of type DESK can be booked.
• Employees can cancel only their own bookings.

The spacing rule

On the same floor and date, no two booked desks may be neighbours.

Each floor has a neighbour_mode that decides which desks count as neighbours.

ORTHOGONAL (default)

The 4 desks sharing an edge: above, below, left, and right.

 .  N  .
 N  X  N
 .  N  .

ALL

All 8 surrounding desks, including diagonals.

 N  N  N
 N  X  N
 N  N  N

X is the desk being booked, and N marks its neighbours.

Edges, corners, and non-desk cells

• Desks on an edge or in a corner simply have fewer neighbours. A corner desk has 2 orthogonal neighbours, or 3 in ALL mode.
• Walkways, walls, and meeting rooms are never neighbours. A desk whose only adjacent cells are walkways has no neighbours.
• Neighbours are computed in one place, the neighbour policy, which reads the mode from the floor. Nothing else hard-codes either mode.

Worked example (ORTHOGONAL)

     c0   c1   c2
r0   D    D    D
r1   D    [B]  D
r2   D    D    —

[B] is booked and — is a walkway.

• Booking r0 c1, r1 c0, r1 c2, or r2 c1 is rejected with SPACING_VIOLATION, because each is directly next to [B].
• Booking r0 c0 is allowed in ORTHOGONAL mode but rejected in ALL mode, because it's diagonal to [B].

Error codes

Code	HTTP	When
DESK_TAKEN	409	The desk is already booked for that date
SPACING_VIOLATION	409	A neighbouring desk is booked for that date
ALREADY_BOOKED_TODAY	409	The employee already has a booking that date
INVALID_DATE	400	The date is in the past or beyond the booking window
NOT_A_DESK	400	The cell isn't bookable
FORBIDDEN	403	Cancelling someone else's booking
NOT_FOUND	404	The desk or booking doesn't exist

The server is the only authority on these rules. The frontend may check the spacing rule early to warn the user, but it never replaces the server's check.