public enum VehicleStatus {
    FREE ,
    BUSY ,
    NOT_WORKING;
}

public enum OrderStatus {
    DELIVERED ,
    PROCESSING , 
    CANCELLED; 
}

public enum PaymentStatus {
    PAID,
    UNPAID;
}

public enum OrderPriority {
    LOW,
    MEDIUM,
    HIGH;
}

// for geographical position of any point
class Location {
	float longitude;
	float latitude;
}

// for the vehicles used for transportation
class Vehicle {
	
	int id;
	String vehicleNo;
	int capacity;
	Location current_position;
	VehicleStatus current_condition;
}

class Truck extends Vehicles{

}

class Bike extends Vehicles{

}

// a new order is created for each order place by any client
class Order{
	int order_id;
	OrderPriority priority_of_order;
    Client owner_of_order;
    Location destination;
    int amount_of_charge;
    List<Item> items;
    int total_weight;
    OrderStatus current_status;
    PaymentStatus status_of_payment;
    Time time_of_order_placed;
    Time time_of_delivery

}

// An order is List of Items
class Item {
	String name;
	int price;
	int volume;
	int weight;
}

class Client {
	int client_id;
	String name;
	Location adress;
}

class Admin{
void take_order (Order order)
void process_order(Order order)
Location track_order(int order_id)
}