Vehicle Rental Service

Build a vehicle rental service: vehicles of two kinds, rentals, and the agency that manages both. Prices are whole dollars (int).

Vehicle in vehicle.gd:

• The constructor takes vin, make, model and daily_rate; available starts as true.
• start_rental() -> bool: returns false when the vehicle is not available; otherwise marks it unavailable and returns true.
• end_rental() makes it available again.
• _to_string() returns MAKE MODEL (VIN: VIN) - Available, or - Rented at the end.

Car in car.gd and Motorcycle in motorcycle.gd extend Vehicle. Their constructors take the four vehicle values plus seats (car) or engine_size (motorcycle). Their _to_string() builds on the parent's text: Car: + vehicle text + - 5 seats, and Motorcycle: + vehicle text + - 600cc.

Rental in rental.gd:

• The constructor takes rental_id, the vehicle object, customer_name and days; is_active starts as true.
• calculate_cost() -> int: the daily rate times the days.
• end_rental() -> bool: false for a rental that already ended; otherwise ends it, ends the vehicle's rental and returns true.
• _to_string(): Rental ID: MAKE MODEL for CUSTOMER, D days, $COST - Active, or - Completed.

RentalAgency in rental_agency.gd:

• The constructor takes agency_name. vehicles is a dictionary from VIN to vehicle, rentals a dictionary from rental id to rental, and next_rental_id starts at 1.
• add_vehicle(vehicle) stores a vehicle under its VIN.
• rent_vehicle(vin, customer_name, days) -> String: returns "" for an unknown VIN, fewer than 1 day, or a vehicle that is not available. Otherwise it starts the vehicle's rental, creates a Rental with the id R1, R2... (the counter goes up only for a successful rental), stores it and returns the id.
• return_vehicle(rental_id) -> bool: false for an unknown id; otherwise returns what the rental's end_rental() returns.
• available_vehicles() -> Array[Vehicle]: the available vehicles, in the order they were added.
• total_revenue() -> int: the sum of the costs of all rentals, active or completed.

A rental stores its vehicle, but a vehicle does not store its rental, so no two objects point at each other. For this input:

Speedy Rentals
car C1|Toyota|Camry|50|5
moto M1|Honda|CBR|40|600
rent C1|Ana|3
rent C1|Ben|2
available
kind M1
rentals
revenue

the output is:

Rented C1 as R1: $150
Cannot rent C1
Available at Speedy Rentals:
- Motorcycle: Honda CBR (VIN: M1) - Available - 600cc
M1: Vehicle true, Car false, Motorcycle true
Rental R1: Toyota Camry for Ana, 3 days, $150 - Active
Revenue: $150

Your code goes in vehicle.gd, car.gd, motorcycle.gd, rental.gd and rental_agency.gd. main.gd holds the supplied input/output code and cannot be edited.