workspace/projects/erp-suite/apps/verticales/retail/backend/src/app.ts

import 'reflect-metadata';
import express, { Application, Request, Response, NextFunction } from 'express';
import cors from 'cors';
import helmet from 'helmet';
import compression from 'compression';
import morgan from 'morgan';

// Route imports
import branchRoutes from './modules/branches/routes/branch.routes';
import posRoutes from './modules/pos/routes/pos.routes';

// Error type
interface AppError extends Error {
  statusCode?: number;
  status?: string;
  isOperational?: boolean;
}

// Create Express app
const app: Application = express();

// Security middleware
app.use(helmet());

// CORS configuration
app.use(cors({
  origin: process.env.CORS_ORIGIN?.split(',') || ['http://localhost:3000', 'http://localhost:5173'],
  credentials: true,
  methods: ['GET', 'POST', 'PUT', 'PATCH', 'DELETE', 'OPTIONS'],
  allowedHeaders: ['Content-Type', 'Authorization', 'X-Tenant-ID', 'X-Branch-ID'],
}));

// Compression
app.use(compression());

// Body parsing
app.use(express.json({ limit: '10mb' }));
app.use(express.urlencoded({ extended: true, limit: '10mb' }));

// Request logging
if (process.env.NODE_ENV !== 'test') {
  app.use(morgan(process.env.NODE_ENV === 'production' ? 'combined' : 'dev'));
}

// Health check endpoint
app.get('/health', (_req: Request, res: Response) => {
  res.json({
    status: 'healthy',
    timestamp: new Date().toISOString(),
    version: process.env.npm_package_version || '0.1.0',
    environment: process.env.NODE_ENV || 'development',
  });
});

// API version info
app.get('/api', (_req: Request, res: Response) => {
  res.json({
    name: 'ERP Retail API',
    version: '0.1.0',
    modules: [
      'branches',
      'pos',
      'cash',
      'inventory',
      'customers',
      'pricing',
      'invoicing',
      'ecommerce',
      'purchases',
    ],
  });
});

// API Routes
app.use('/api/branches', branchRoutes);
app.use('/api/pos', posRoutes);
// TODO: Add remaining route modules as they are implemented
// app.use('/api/cash', cashRouter);
// app.use('/api/inventory', inventoryRouter);
// app.use('/api/customers', customersRouter);
// app.use('/api/pricing', pricingRouter);
// app.use('/api/invoicing', invoicingRouter);
// app.use('/api/ecommerce', ecommerceRouter);
// app.use('/api/purchases', purchasesRouter);

// 404 handler
app.use((_req: Request, res: Response) => {
  res.status(404).json({
    success: false,
    error: {
      code: 'NOT_FOUND',
      message: 'The requested resource was not found',
    },
  });
});

// Global error handler
app.use((err: AppError, _req: Request, res: Response, _next: NextFunction) => {
  const statusCode = err.statusCode || 500;
  const status = err.status || 'error';

  // Log error
  console.error('Error:', {
    message: err.message,
    stack: process.env.NODE_ENV === 'development' ? err.stack : undefined,
    statusCode,
  });

  // Send response
  res.status(statusCode).json({
    success: false,
    error: {
      code: status.toUpperCase().replace(/ /g, '_'),
      message: err.isOperational ? err.message : 'An unexpected error occurred',
      ...(process.env.NODE_ENV === 'development' && { stack: err.stack }),
    },
  });
});

export default app;