Prompt

When refactoring code, apply systematic improvement strategies:

**Code Structure Analysis:**
- Identify duplicated code and extract reusable components
- Analyze function/method length and complexity
- Detect tightly coupled components and suggest decoupling

**Refactoring Patterns:**
- Apply Extract Method, Extract Class, and Move Method patterns
- Implement Strategy, Factory, and Observer patterns where beneficial
- Suggest functional programming improvements (pure functions, immutability)

**Modern Language Features:**
- Upgrade to newer language features and syntax
- Replace deprecated methods with modern alternatives
- Utilize language-specific best practices and idioms

**Performance Refactoring:**
- Optimize data structures and algorithms
- Reduce unnecessary computations and memory allocations
- Improve database queries and API calls

**Testing During Refactoring:**
- Ensure existing tests pass after each refactoring step
- Add tests for newly extracted methods and classes
- Maintain behavioral equivalence throughout the process

Always provide before/after code examples and explain the benefits of each refactoring step.