refactor

# SOLID refactoring assistant Analyze code for SOLID violations and suggest targeted improvements. ## Purpose Identify refactoring opportunities based on: - SOLID principle violations - Code smells and anti-patterns - Complexity metrics - Duplication detection ## Instructions ### Step 1: Scope analysis Determine the refactoring scope from user input: - Single file: Deep analysis - Directory: Pattern detection across files - Function/class: Focused extraction suggestions ```bash # Get file/directory stats if [ -f "$TARGET" ]; then wc -l "$TARGET" echo "Single file analysis" elif [ -d "$TARGET" ]; then find "$TARGET" -type f \( -name "*.ts" -o -name "*.js" -o -name "*.py" \) | wc -l echo "Directory analysis" fi ``` ### Step 2: SOLID violations detection #### S - single responsibility Look for: - Files > 300 lines - Functions > 50 lines - Classes with > 10 methods - Mixed concerns (data + UI + business logic) ```bash # Find large files find . -name "*.{ts,js,py}" -exec wc -l {} + 2>/dev/null | sort -rn | head -10 # Functions with high line count (approximate) grep -rn "function\|def \|fn " --include="*.{ts,js,py,rs}" . | head -20 ``` #### O - open/closed principle Look for: - Switch/case statements on types - Repeated if/else type checking - Direct modifications vs extensions #### L - liskov substitution Look for: - Overridden methods that throw "not implemented" - Type checks before method calls - Empty method overrides #### I - interface segregation Look for: - Large interfaces (> 10 methods) - Classes implementing unused interface methods - Fat service classes #### D - dependency inversion Look for: - Direct instantiation of dependencies (`new Service()`) - Hardcoded class references - Missing dependency injection ### Step 3: Code smells ```bash # Duplication patterns grep -rn --include="*.{ts,js,py}" . 2>/dev/null | \ awk -F: '{print $3}' | sort | uniq -c | sort -rn | head -10 # Long parameter lists (> 4 params) grep -rn "function.*,.*,.*,.*," --include="*.{ts,js}" . 2>/dev/null | head -10 # Deep nesting (4+ levels) grep -rn "^\s\{16,\}" --include="*.{ts,js,py}" . 2>/dev/null | head -10 ``` ### Step 4: Complexity assessment For each issue found, assess: - **Impact**: How much code is affected? - **Risk**: What could break? - **Effort**: Lines to change, tests needed? ## Output format --- ### 🔧 Refactoring analysis **Target**: [file/directory] **Lines Analyzed**: [count] ### 📊 SOLID scorecard | Principle | Status | Issues Found | |-----------|--------|--------------| | Single Responsibility | 🟡 | 3 large classes | | Open/Closed | 🟢 | OK | | Liskov Substitution | 🟢 | OK | | Interface Segregation | 🔴 | 2 fat interfaces | | Dependency Inversion | 🟡 | 5 direct instantiations | ### 🎯 Priority refactorings #### 1. [Highest Impact] - Extract class from `UserService` **Violation**: Single Responsibility **Current**: 450 lines handling auth + profile + notifications **Suggested**: ``` UserService.ts (450 lines) ↓ Extract AuthService.ts (~150 lines) ProfileService.ts (~150 lines) NotificationService.ts (~100 lines) ``` **Risk**: Medium (update imports) **Tests Needed**: Update dependency injection in tests #### 2. [Second Priority] - Replace switch with polymorphism **Location**: `src/handlers/payment.ts:45` **Current**: ```typescript switch (paymentType) { case 'card': // 50 lines case 'bank': // 50 lines case 'crypto': // 50 lines } ``` **Suggested**: Strategy pattern with `PaymentProcessor` interface **Risk**: Low (isolated change) ### 📝 Code smells | Smell | Location | Severity | |-------|----------|----------| | Long Method | `api.ts:calculateTotal` (120 lines) | 🟠 High | | Duplicate Code | `utils/*.ts` (3 similar blocks) | 🟡 Medium | | Deep Nesting | `parser.ts:parse` (6 levels) | 🟡 Medium | ### 🚀 Quick wins (low risk, high value) 1. Extract `validateEmail()` to shared utils (used in 4 places) 2. Replace magic numbers with named constants 3. Add early returns to reduce nesting in `processOrder()` ### ⚠️ Technical debt notes - [Item to track for future sprints] --- ## Refactoring safety checklist Before applying suggestions: - [ ] Tests exist for affected code - [ ] Create feature branch - [ ] Commit current state - [ ] Apply one refactoring at a time - [ ] Run tests after each change - [ ] Review diff before committing ## Usage **Analyze specific file:** ``` /refactor src/services/user.ts ``` **Analyze directory:** ``` /refactor src/api/ ``` **Focus on specific principle:** ``` /refactor --focus=srp src/services/ ``` **With complexity threshold:** ``` /refactor --threshold=high ``` ## References - Martin Fowler's Refactoring Catalog - Clean Code by Robert C. Martin - SOLID principles by Robert C. Martin $ARGUMENTS