Design a Parking Lot System

Apply object-oriented design to model a multi-level parking lot with different vehicle types, payment strategies, and spot allocation.

Functional Requirements

• Support multiple vehicle types: motorcycles, cars, trucks
• Multiple spot sizes: small, medium, large
• Multi-level structure with independent floors
• Issue and process parking tickets
• Calculate fees based on duration and vehicle type
• Track real-time availability

Design Challenges

• Model spot allocation with the Strategy pattern
• Apply polymorphism for vehicle type handling
• Separate pricing concerns from the core domain

Questions to Consider

• How do you model the relationship between Vehicle, Spot, and Ticket?
• How do you make the pricing strategy extensible without modifying existing code?
• How do you enforce that a motorcycle cannot take a large spot when smalls are available?