RestaurantClassDiagramOCL.puml

@startuml
class User {
    - userID: String
    - name: String
    - email: String
    - password: String
    + register(): void
    + login(): void
    + logout(): void
}

class Customer extends User {
    + viewTables(): void
    + makeReservation(): void
    + modifyReservation(): void
    + cancelReservation(): void
}

class Staff extends User {
    - staffID: String
    - role: String
    + manageReservations(): void
    + updateTableAvailability(): void
}

class Reservation {
    - reservationID: String
    - date: Date
    - time: Time
    - specialRequests: String
    + createReservation(): void
    + modifyReservation(): void
    + cancelReservation(): void
}

class Table {
    - tableID: String
    - capacity: int
    - isAvailable: boolean
    + updateAvailability(): void
}

note right of Reservation
        A reservation must be associated with a table that is available.
        inv: self.table.isAvailable = true

        A reservation must have a valid date and time.
        inv: self.date <> null and self.time <> null
end note

note right of Table
        A table cannot be reserved if it is not available.
        inv: self.isAvailable = true implies self.reservations->size() = 0
end note

note right of Customer
        A customer cannot make a reservation if they are logged out.
        inv: self.isLoggedIn() implies self.makeReservation() = true
end note

note right of User
        Password must be at least 8 characters long, contain at least one uppercase letter, one lowercase letter, and one number.
        inv: self.password.length() >= 8 and self.password.matches('[a-zA-Z0-9]*') and self.password.matches('.*[A-Z].*') and self.password.matches('.*[0-9].*')

        Email must follow a valid format.
        inv: self.email.matches('[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,}')
end note

User "1" --> "0..*" Reservation
Reservation "1" --> "1" Table

Staff "1" --> "0..*" Table
Staff "1" --> "0..*" Reservation
@enduml