KISS DRY SOLID YAGNI Refactor

Refactor selected files (or current diff) to align with KISS, DRY, SOLID, and YAGNI while strictly preserving behavior.

Usage

/refactor [file_or_pattern]

Examples:

/refactor                              # Refactor current diff
/refactor src/core/*.py                # Refactor specific files

Principles Applied (In Order)

1. KISS (Keep It Simple, Stupid)

• Flatten deeply nested control flow with guard clauses
• Remove unnecessary wrapper layers and pass-through indirections
• Replace complex boolean expressions with well-named predicates
• Prefer straightforward data flow over cleverness
• Keep functions small and cohesive
• Inline trivial abstractions that add indirection without reducing complexity

2. YAGNI (You Aren't Gonna Need It)

• Remove dead/unreachable code, unused params/locals/imports/exports
• Delete speculative abstractions with single use and no near-term reuse
• Collapse configuration surface to what's actually used
• Keep public APIs stable (SKIP if removal risks breakage)

3. DRY (Don't Repeat Yourself)

• Detect duplication: copy/paste blocks, repeated queries/hooks/effects
• Extract shared logic into small, well-named helpers
• Consolidate config/literals into constants
• Remove magic numbers/strings
• Keep helpers close to use-sites unless broadly reusable

4. SOLID

• Single Responsibility: One function/class = one reason to change
• Open/Closed: Prefer extension points over editing core logic (when warranted)
• Liskov Substitution: Subtypes uphold base contracts
• Interface Segregation: Break wide interfaces into focused ones
• Dependency Inversion: Depend on abstractions, inject dependencies

Constraints

• Preserve behavior: No functional changes
• Preserve side effects: Logging and error semantics untouched
• Maintain readability: No over-abstraction
• Keep public APIs stable: Skip changes that risk breakage
• Same or better performance: No extra allocations in hot paths
• Follow repo patterns: TypeScript types, React hooks rules, Python async-first
• Honor AIDEV- comments*: Update when modifying related code
• No tests unless asked

Language Specifics

React/TypeScript:

• Prefer small pure utilities, stable hook signatures, typed params/returns
• Don't break Rules of Hooks
• Keep component props stable

Python:

• Prefer pure functions and dataclasses
• Keep docstrings/typing intact
• Avoid unnecessary try/except, prefer guard clauses

Output

Concise rationale summary grouped by principle:

## KISS
- Flattened nested if/else in `query.py:process_result` using guard clauses

## YAGNI
- Removed unused `legacy_mode` parameter in `handler.py:handle_request`
- SKIPPED: `config.defaults` removal - used by external clients

## DRY
- Extracted `validate_user_input()` helper in `api.py` (was duplicated 3x)

## SOLID
- Split `UserManager` into `UserReader` and `UserWriter` (SRP)