Refactor for Clean Code

Refactor the following code to be clean, modular, and aligned with TypeScript best practices.

<span class="workshop-var-empty">{{code}}</span>

Apply these principles:

1. Single Responsibility — Each function should do one thing well
2. Descriptive naming — Variables and functions should reveal intent
3. Eliminate nesting — Break deeply nested logic into smaller functions or use early returns
4. Remove duplication — Extract repeated patterns into reusable utilities
5. Simplify conditionals — Replace complex if/else chains with clearer patterns
6. Add type safety — Strengthen type definitions where applicable

For each change, explain:

• What you changed
• Why it's better
• Any trade-offs introduced

Show the complete refactored code, followed by a before/after comparison of key metrics (line count, nesting depth, number of functions).