/**
 * REST API Server
 * Provides RESTful API for Brazil SWIFT Operations Platform
 */

import 'dotenv/config';
import express, { Express, Request, Response, NextFunction } from 'express';
import cors from 'cors';
import { getLogger } from '@brazil-swift-ops/utils';
import { evaluateTransaction } from '@brazil-swift-ops/rules-engine';
import type { Transaction } from '@brazil-swift-ops/types';
import { initializeDatabase, closeDatabase } from './db/connection';
import { runMigrations } from './db/migrate';
import { seedDatabase } from './db/seed';
import authRoutes from './routes/auth';

const app: Express = express();
const logger = getLogger();
const PORT = process.env.PORT || 3000;

// Middleware
app.use(cors());
app.use(express.json());
app.use((req: Request, res: Response, next: NextFunction) => {
  const correlationId = `req-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
  logger.setCorrelationId(correlationId);
  req.headers['x-correlation-id'] = correlationId;
  next();
});

// Health checks
import { healthCheckHandler, readinessCheckHandler, livenessCheckHandler } from './health';

app.get('/health', healthCheckHandler);
app.get('/health/ready', readinessCheckHandler);
app.get('/health/live', livenessCheckHandler);

// Import all route handlers
import transactionRoutes from './routes/transactions';
import accountRoutes from './routes/accounts';
import userRoutes from './routes/users';
import complianceRoutes from './routes/compliance';
import reportsRoutes from './routes/reports';
import fxContractRoutes from './routes/fx-contracts';
import metricsRoutes from './routes/metrics';
import { errorHandler } from './middleware/errorHandler';
import { incrementCounter, recordHistogram } from './monitoring/metrics';

// Request metrics middleware
app.use((req: Request, res: Response, next: NextFunction) => {
  const startTime = Date.now();
  incrementCounter('http_requests_total', { method: req.method, path: req.path });

  res.on('finish', () => {
    const duration = Date.now() - startTime;
    recordHistogram('http_request_duration_ms', duration, {
      method: req.method,
      status: res.statusCode.toString(),
    });
    incrementCounter('http_responses_total', {
      method: req.method,
      status: res.statusCode.toString(),
    });
  });

  next();
});

// Register routes
app.use('/api/v1/auth', authRoutes);
app.use('/api/v1/transactions', transactionRoutes);
app.use('/api/v1/accounts', accountRoutes);
app.use('/api/v1/users', userRoutes);
app.use('/api/v1/compliance', complianceRoutes);
app.use('/api/v1/reports', reportsRoutes);
app.use('/api/v1/fx-contracts', fxContractRoutes);
app.use('/metrics', metricsRoutes);

// Legacy evaluate transaction endpoint
app.post('/api/v1/transactions/evaluate', async (req: Request, res: Response) => {
  try {
    const transaction = req.body as Transaction;
    const result = evaluateTransaction(transaction);
    
    logger.info('Transaction evaluated', { transactionId: transaction.id });
    
    res.json({
      success: true,
      data: result,
    });
  } catch (error) {
    logger.error('Error evaluating transaction', error as Error);
    res.status(500).json({
      success: false,
      error: 'Failed to evaluate transaction',
    });
  }
});

// Error handler (must be last)
app.use(errorHandler);

// Initialize database and start server
let server: any;

async function startServer() {
  try {
    // Initialize database
    await initializeDatabase();
    console.log('✓ Database initialized');

    // Run migrations
    await runMigrations();
    console.log('✓ Migrations completed');

    // Seed database with initial data
    await seedDatabase();
    console.log('✓ Database seeded');

    // Start server
    server = app.listen(PORT, () => {
      logger.info(`API server started on port ${PORT}`);
    });

    // Handle graceful shutdown
    process.on('SIGTERM', shutdown);
    process.on('SIGINT', shutdown);
  } catch (error) {
    console.error('Failed to start server:', error);
    process.exit(1);
  }
}

async function shutdown() {
  console.log('\nShutting down gracefully...');
  if (server) {
    server.close(async () => {
      await closeDatabase();
      console.log('Server closed');
      process.exit(0);
    });
  }
}

// Start server (only if running directly, not when imported)
if (typeof require !== 'undefined' && require.main === module) {
  startServer();
}

export default app;