refactor

Development

Analyze code for SOLID violations and suggest targeted improvements

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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

# 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)

# 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

# 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:

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