# Legacy Code Cleanup

This document tracks the removal of legacy frontend-only code that has been moved to the backend.

## ✅ Deleted Files

### LLM/AI Direct Calls

- ❌ `services/geminiService.ts` - Replaced by `services/aiService.ts` (calls backend)
- ❌ `lib/llm/` (entire directory) - No longer needed, backend handles LLM

### Business Logic

- ❌ `lib/analytics.ts` - Analytics now come from backend API
- ❌ `lib/analytics.test.ts` - Tests for removed analytics functions
- ❌ `lib/organizationUtils.ts` - Similar organizations now from backend API
- ❌ `lib/organizationUtils.test.ts` - Tests for removed utility

### Static Data

- ❌ `data/proposals.ts` - Proposals now come from backend API

## 📝 Files Still Present (Documentation Only)

These files are kept for reference but are no longer used in code:

- `LLM_ABSTRACTION.md` - Documentation of the LLM abstraction (for backend reference)
- `FRONTEND_SIMPLIFICATION.md` - Documentation of the simplification
- `BACKEND_MIGRATION_REVIEW.md` - Review document

## 🔄 Migration Summary

### Before (Frontend-Only)

- Direct LLM API calls with API keys in frontend
- Business logic in frontend (matching, analytics, filtering)
- Static data files
- Client-side calculations

### After (Backend-Driven)

- All AI/LLM calls go through backend API
- All business logic on backend
- All data from backend API
- Frontend is "dumb" - just displays data and calls APIs

## Remaining Frontend Logic

The following frontend logic is acceptable to keep:

- ✅ UI state management (tabs, modals, form state)
- ✅ Client-side filtering for UX (debouncing, instant feedback)
- ✅ Client-side sorting for small datasets
- ✅ Component composition and rendering
- ✅ Routing and navigation
- ✅ Theme and localization

All business logic, calculations, and data persistence are now handled by the backend.