refactoring-agent

CRITICAL: Gradual, safe refactoring. Never break existing functionality. Test after each change.

Refactoring Workflow

1. Assessment

• Identify current state (file locations, patterns)
• Document what needs to change
• Check dependencies (other features using this code)
• Estimate risk level (low/medium/high)

2. Planning

• Create refactoring checklist
• Determine order (least risky first)
• Identify tests needing updates
• Get approval before proceeding

3. Execution

• Create new structure alongside old (no deletion yet)
• Migrate logic incrementally
• Update tests to new structure
• Verify all tests pass
• Add @Deprecated annotations to old code
• Update all references
• Remove old code only after full migration

4. Validation

• Run flutter analyze
• Full test suite passes
• Manual smoke testing
• Document changes in PR

Migration Pattern

Legacy → Refactored (data/domain/view)

See design-architecture-skill for target structure

Common Migrations

From	To	Steps
Mixed concerns API	RemoteDatasource	Extract API calls, use retrofit
Response models	DTOs + Domain Models	Separate data layer from business logic
Legacy state (Provider/ChangeNotifier/setState)	Modern state management	Extract state logic, apply chosen pattern
Manual DI	Injectable	Add @injectable, @factoryMethod

Example

// ❌ Legacy: Mixed concerns
class FeaturesApi {
  Future<List<Feature>> fetchFeatures() async {
    final response = await http.get(url);
    return (json.decode(response.body) as List)
        .map((e) => Feature.fromJson(e))
        .toList();
  }
}

// ✅ Refactored: Separated concerns
// 1. RemoteDatasource (data layer)
@RestApi()
abstract class FeaturesRemoteDatasource {
  @GET('/features')
  Future<List<FeatureDto>> fetchFeatures();
}

// 2. Repository (data layer)
class FeaturesRepositoryImpl implements FeaturesRepository {
  final FeaturesRemoteDatasource _datasource;
  Future<List<Feature>> fetchFeatures() async {
    final dtos = await _datasource.fetchFeatures();
    return dtos.map((dto) => dto.toDomain()).toList();
  }
}