# Codebase Structure

**Analysis Date:** 2026-02-24

## Directory Layout

```
cim_summary/
├── backend/                        # Express.js + TypeScript backend (Node.js)
│   ├── src/
│   │   ├── index.ts               # Express app + Firebase Functions exports
│   │   ├── controllers/           # Request handlers
│   │   ├── models/                # Database access + schema
│   │   ├── services/              # Business logic + external integrations
│   │   ├── routes/                # Express route definitions
│   │   ├── middleware/            # Express middleware (auth, validation, error)
│   │   ├── config/                # Configuration (env, firebase, supabase)
│   │   ├── utils/                 # Utilities (logger, validation, parsing)
│   │   ├── types/                 # TypeScript type definitions
│   │   ├── scripts/               # One-off CLI scripts (diagnostics, setup)
│   │   ├── assets/                # Static assets (HTML templates)
│   │   └── __tests__/             # Test suites (unit, integration, acceptance)
│   ├── package.json               # Node dependencies
│   ├── tsconfig.json              # TypeScript config
│   ├── .eslintrc.json             # ESLint config
│   └── dist/                       # Compiled JavaScript (generated)
│
├── frontend/                       # React + Vite + TypeScript frontend
│   ├── src/
│   │   ├── main.tsx               # React entry point
│   │   ├── App.tsx                # Root component with routing
│   │   ├── components/            # React components (UI)
│   │   ├── services/              # API clients (documentService, authService)
│   │   ├── contexts/              # React Context (AuthContext)
│   │   ├── config/                # Configuration (env, firebase)
│   │   ├── types/                 # TypeScript interfaces
│   │   ├── utils/                 # Utilities (validation, cn, auth debug)
│   │   └── assets/                # Static images and icons
│   ├── package.json               # Node dependencies
│   ├── tsconfig.json              # TypeScript config
│   ├── vite.config.ts             # Vite bundler config
│   ├── eslintrc.json              # ESLint config
│   ├── tailwind.config.js          # Tailwind CSS config
│   ├── postcss.config.js           # PostCSS config
│   └── dist/                       # Built static assets (generated)
│
├── .planning/                      # GSD planning directory
│   └── codebase/                  # Codebase analysis documents
│
├── package.json                    # Monorepo root package (if used)
├── .git/                           # Git repository
├── .gitignore                      # Git ignore rules
├── .cursorrules                    # Cursor IDE configuration
├── README.md                       # Project overview
├── CONFIGURATION_GUIDE.md          # Setup instructions
├── CODEBASE_ARCHITECTURE_SUMMARY.md # Existing architecture notes
└── [PDF documents]                 # Sample CIM documents for testing
```

## Directory Purposes

**backend/src/:**
- Purpose: All backend server code
- Contains: TypeScript source files
- Key files: `index.ts` (main app), routes, controllers, services, models

**backend/src/controllers/:**
- Purpose: HTTP request handlers
- Contains: `documentController.ts`, `authController.ts`
- Functions: Map HTTP requests to service calls, handle validation, construct responses

**backend/src/services/:**
- Purpose: Business logic and external integrations
- Contains: Document processing, LLM integration, file storage, database, job queue
- Key files:
  - `unifiedDocumentProcessor.ts` - Orchestrator, strategy selection
  - `singlePassProcessor.ts` - 2-LLM extraction (current default)
  - `optimizedAgenticRAGProcessor.ts` - Advanced agentic processing (stub)
  - `documentAiProcessor.ts` - Google Document AI OCR
  - `llmService.ts` - LLM API calls (Anthropic/OpenAI/OpenRouter)
  - `jobQueueService.ts` - Async job queue (in-memory, EventEmitter)
  - `jobProcessorService.ts` - Dequeue and execute jobs
  - `fileStorageService.ts` - GCS signed URLs and upload
  - `vectorDatabaseService.ts` - Supabase pgvector operations
  - `pdfGenerationService.ts` - Puppeteer PDF rendering
  - `uploadProgressService.ts` - Track upload status
  - `uploadMonitoringService.ts` - Monitor processing progress
  - `llmSchemas.ts` - Zod schemas for LLM extraction (CIMReview, financial data)

**backend/src/models/:**
- Purpose: Database access layer and schema definitions
- Contains: Document, User, ProcessingJob, Feedback models
- Key files:
  - `types.ts` - TypeScript interfaces (Document, ProcessingJob, ProcessingStatus)
  - `DocumentModel.ts` - Document CRUD with retry logic
  - `ProcessingJobModel.ts` - Job tracking in database
  - `UserModel.ts` - User management
  - `VectorDatabaseModel.ts` - Vector embedding queries
  - `migrate.ts` - Database migrations
  - `seed.ts` - Test data seeding
  - `migrations/` - SQL migration files

**backend/src/routes/:**
- Purpose: Express route definitions
- Contains: Route handlers and middleware bindings
- Key files:
  - `documents.ts` - GET/POST/PUT/DELETE document endpoints
  - `vector.ts` - Vector search endpoints
  - `monitoring.ts` - Health and status endpoints
  - `documentAudit.ts` - Audit log endpoints

**backend/src/middleware/:**
- Purpose: Express middleware for cross-cutting concerns
- Contains: Authentication, validation, error handling
- Key files:
  - `firebaseAuth.ts` - Firebase ID token verification
  - `errorHandler.ts` - Global error handling + correlation ID
  - `notFoundHandler.ts` - 404 handler
  - `validation.ts` - Request validation (UUID, pagination)

**backend/src/config/:**
- Purpose: Configuration and initialization
- Contains: Environment setup, service initialization
- Key files:
  - `env.ts` - Environment variable validation (Joi schema)
  - `firebase.ts` - Firebase Admin SDK initialization
  - `supabase.ts` - Supabase client and pool setup
  - `database.ts` - PostgreSQL connection (legacy)
  - `errorConfig.ts` - Error handling config

**backend/src/utils/:**
- Purpose: Shared utility functions
- Contains: Logging, validation, parsing
- Key files:
  - `logger.ts` - Winston logger setup (console + file transports)
  - `validation.ts` - UUID and pagination validators
  - `googleServiceAccount.ts` - Google Cloud credentials resolution
  - `financialExtractor.ts` - Financial data parsing (deprecated for single-pass)
  - `templateParser.ts` - CIM template utilities
  - `auth.ts` - Authentication helpers

**backend/src/scripts/:**
- Purpose: One-off CLI scripts for diagnostics and setup
- Contains: Database setup, testing, monitoring
- Key files:
  - `setup-database.ts` - Initialize database schema
  - `monitor-document-processing.ts` - Watch job queue status
  - `check-current-job.ts` - Debug stuck jobs
  - `test-full-llm-pipeline.ts` - End-to-end testing
  - `comprehensive-diagnostic.ts` - System health check

**backend/src/__tests__/:**
- Purpose: Test suites
- Contains: Unit, integration, acceptance tests
- Subdirectories:
  - `unit/` - Isolated component tests
  - `integration/` - Multi-component tests
  - `acceptance/` - End-to-end flow tests
  - `mocks/` - Mock data and fixtures
  - `utils/` - Test utilities

**frontend/src/:**
- Purpose: All frontend code
- Contains: React components, services, types

**frontend/src/components/:**
- Purpose: React UI components
- Contains: Page components, reusable widgets
- Key files:
  - `DocumentUpload.tsx` - File upload UI with drag-and-drop
  - `DocumentList.tsx` - List of processed documents
  - `DocumentViewer.tsx` - View and edit extracted data
  - `ProcessingProgress.tsx` - Real-time processing status
  - `UploadMonitoringDashboard.tsx` - Admin view of active jobs
  - `LoginForm.tsx` - Firebase auth login UI
  - `ProtectedRoute.tsx` - Route guard for authenticated pages
  - `Analytics.tsx` - Document analytics and statistics
  - `CIMReviewTemplate.tsx` - Display extracted CIM review data

**frontend/src/services/:**
- Purpose: API clients and external service integration
- Contains: HTTP clients for backend
- Key files:
  - `documentService.ts` - Document API calls (upload, list, process, status)
  - `authService.ts` - Firebase authentication (login, logout, token)
  - `adminService.ts` - Admin-only operations

**frontend/src/contexts/:**
- Purpose: React Context for global state
- Contains: AuthContext for user and authentication state
- Key files:
  - `AuthContext.tsx` - User, token, login/logout state

**frontend/src/config/:**
- Purpose: Configuration
- Contains: Environment variables, Firebase setup
- Key files:
  - `env.ts` - VITE_API_BASE_URL and other env vars
  - `firebase.ts` - Firebase client initialization

**frontend/src/types/:**
- Purpose: TypeScript interfaces
- Contains: API response types, component props
- Key files:
  - `auth.ts` - User, LoginCredentials, AuthContextType

**frontend/src/utils/:**
- Purpose: Shared utility functions
- Contains: Validation, CSS utilities
- Key files:
  - `validation.ts` - Email, password validators
  - `cn.ts` - Classname merger (clsx wrapper)
  - `authDebug.ts` - Authentication debugging helpers

## Key File Locations

**Entry Points:**
- `backend/src/index.ts` - Main Express app and Firebase Functions exports
- `frontend/src/main.tsx` - React entry point
- `frontend/src/App.tsx` - Root component with routing

**Configuration:**
- `backend/src/config/env.ts` - Environment variable schema and validation
- `backend/src/config/firebase.ts` - Firebase Admin SDK setup
- `backend/src/config/supabase.ts` - Supabase client and connection pool
- `frontend/src/config/firebase.ts` - Firebase client configuration
- `frontend/src/config/env.ts` - Frontend environment variables

**Core Logic:**
- `backend/src/services/unifiedDocumentProcessor.ts` - Main document processing orchestrator
- `backend/src/services/singlePassProcessor.ts` - Single-pass 2-LLM strategy
- `backend/src/services/llmService.ts` - LLM API integration with retry
- `backend/src/services/jobQueueService.ts` - Background job queue
- `backend/src/services/vectorDatabaseService.ts` - Vector search implementation

**Testing:**
- `backend/src/__tests__/unit/` - Unit tests
- `backend/src/__tests__/integration/` - Integration tests
- `backend/src/__tests__/acceptance/` - End-to-end tests

**Database:**
- `backend/src/models/types.ts` - TypeScript type definitions
- `backend/src/models/DocumentModel.ts` - Document CRUD operations
- `backend/src/models/ProcessingJobModel.ts` - Job tracking
- `backend/src/models/migrations/` - SQL migration files

**Middleware:**
- `backend/src/middleware/firebaseAuth.ts` - JWT authentication
- `backend/src/middleware/errorHandler.ts` - Global error handling
- `backend/src/middleware/validation.ts` - Input validation

**Logging:**
- `backend/src/utils/logger.ts` - Winston logger configuration

## Naming Conventions

**Files:**
- Controllers: `{resource}Controller.ts` (e.g., `documentController.ts`)
- Services: `{service}Service.ts` or descriptive (e.g., `llmService.ts`, `singlePassProcessor.ts`)
- Models: `{Entity}Model.ts` (e.g., `DocumentModel.ts`)
- Routes: `{resource}.ts` (e.g., `documents.ts`)
- Middleware: `{purpose}Handler.ts` or `{purpose}.ts` (e.g., `firebaseAuth.ts`)
- Types/Interfaces: `types.ts` or `{name}Types.ts`
- Tests: `{file}.test.ts` or `{file}.spec.ts`

**Directories:**
- Plurals for collections: `services/`, `models/`, `utils/`, `routes/`, `controllers/`
- Singular for specific features: `config/`, `middleware/`, `types/`, `contexts/`
- Nested by feature in larger directories: `__tests__/unit/`, `models/migrations/`

**Functions/Variables:**
- Camel case: `processDocument()`, `getUserId()`, `documentId`
- Constants: UPPER_SNAKE_CASE: `MAX_RETRIES`, `TIMEOUT_MS`
- Private methods: Prefix with `_` or use TypeScript `private`: `_retryOperation()`

**Classes:**
- Pascal case: `DocumentModel`, `JobQueueService`, `SinglePassProcessor`
- Service instances exported as singletons: `export const llmService = new LLMService()`

**React Components:**
- Pascal case: `DocumentUpload.tsx`, `ProtectedRoute.tsx`
- Hooks: `use{Feature}` (e.g., `useAuth` from AuthContext)

## Where to Add New Code

**New Document Processing Strategy:**
- Primary code: `backend/src/services/{strategyName}Processor.ts`
- Schema: Add types to `backend/src/services/llmSchemas.ts`
- Integration: Register in `backend/src/services/unifiedDocumentProcessor.ts`
- Tests: `backend/src/__tests__/integration/{strategyName}.test.ts`

**New API Endpoint:**
- Route: `backend/src/routes/{resource}.ts`
- Controller: `backend/src/controllers/{resource}Controller.ts`
- Service: `backend/src/services/{resource}Service.ts` (if needed)
- Model: `backend/src/models/{Resource}Model.ts` (if database access)
- Tests: `backend/src/__tests__/integration/{endpoint}.test.ts`

**New React Component:**
- Component: `frontend/src/components/{ComponentName}.tsx`
- Types: Add to `frontend/src/types/` or inline in component
- Services: Use existing `frontend/src/services/documentService.ts`
- Tests: `frontend/src/__tests__/{ComponentName}.test.tsx` (if added)

**Shared Utilities:**
- Backend: `backend/src/utils/{utility}.ts`
- Frontend: `frontend/src/utils/{utility}.ts`
- Avoid code duplication - consider extracting common patterns

**Database Schema Changes:**
- Migration file: `backend/src/models/migrations/{timestamp}_{description}.sql`
- TypeScript interface: Update `backend/src/models/types.ts`
- Model methods: Update corresponding `*Model.ts` file
- Run: `npm run db:migrate` in backend

**Configuration Changes:**
- Environment: Update `backend/src/config/env.ts` (Joi schema)
- Frontend env: Update `frontend/src/config/env.ts`
- Firebase secrets: Use `firebase functions:secrets:set VAR_NAME`
- Local dev: Add to `.env` file (gitignored)

## Special Directories

**backend/src/__tests__/mocks/:**
- Purpose: Mock data and fixtures for testing
- Generated: No (manually maintained)
- Committed: Yes
- Usage: Import in tests for consistent test data

**backend/src/scripts/:**
- Purpose: One-off CLI utilities for development and operations
- Generated: No (manually maintained)
- Committed: Yes
- Execution: `ts-node src/scripts/{script}.ts` or `npm run {script}`

**backend/src/assets/:**
- Purpose: Static HTML templates for PDF generation
- Generated: No (manually maintained)
- Committed: Yes
- Usage: Rendered by Puppeteer in `pdfGenerationService.ts`

**backend/src/models/migrations/:**
- Purpose: Database schema migration SQL files
- Generated: No (manually created)
- Committed: Yes
- Execution: Run via `npm run db:migrate`

**frontend/src/assets/:**
- Purpose: Images, icons, logos
- Generated: No (manually added)
- Committed: Yes
- Usage: Import in components (e.g., `bluepoint-logo.png`)

**backend/dist/ and frontend/dist/:**
- Purpose: Compiled JavaScript and optimized bundles
- Generated: Yes (build output)
- Committed: No (gitignored)
- Regeneration: `npm run build` in respective directory

**backend/node_modules/ and frontend/node_modules/:**
- Purpose: Installed dependencies
- Generated: Yes (npm install)
- Committed: No (gitignored)
- Regeneration: `npm install`

**backend/logs/:**
- Purpose: Runtime log files
- Generated: Yes (runtime)
- Committed: No (gitignored)
- Contents: `error.log`, `upload.log`, combined logs

---

*Structure analysis: 2026-02-24*