import { NestFactory } from '@nestjs/core';
import { ValidationPipe } from '@nestjs/common';
import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
import { ConfigService } from '@nestjs/config';
import helmet from 'helmet';
import { AppModule } from './app.module';
import { writeFileSync } from 'fs';
import { join } from 'path';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  const configService = app.get(ConfigService);

  // Security
  app.use(helmet());
  app.enableCors({
    origin: [
      'http://localhost:3000',     // local Swagger UI
      'https://editor.swagger.io', // Swagger Editor online
    ],
    methods: 'GET,HEAD,PUT,PATCH,POST,DELETE,OPTIONS',
    credentials: true,
  });

  // ✅ Global prefix
  const globalPrefix = configService.get('API_PREFIX', 'api/v1');
  app.setGlobalPrefix(globalPrefix);

  // Request logging middleware
  app.use((req, res, next) => {
    console.log(`📝 ${new Date().toISOString()} - ${req.method} ${req.url}`);
    next();
  });

  // Global validation pipe
  app.useGlobalPipes(
    new ValidationPipe({
      whitelist: true,
      forbidNonWhitelisted: true,
      transform: true,
      transformOptions: {
        enableImplicitConversion: true,
      },
    }),
  );
  const port = configService.get('PORT', 3000);

  // Swagger documentation (only in development)
  if (configService.get('NODE_ENV') !== 'production') {
    const config = new DocumentBuilder()
      .setTitle('NestJS Serverless User CRUD API')
      .setDescription('Professional NestJS serverless application with user CRUD and authentication')
      .setVersion(configService.get('API_VERSION', '1.0.0'))
      .addBearerAuth()
      .addServer(`${process.env.SERVER_URL}/`, 'Local Server')
      .build();

    const document = SwaggerModule.createDocument(app, config);
    SwaggerModule.setup('api/docs', app, document);

    const outputPath = join(process.cwd(), 'swagger.json');
    writeFileSync(outputPath, JSON.stringify(document, null, 2), 'utf8');
    console.log(`✅ Swagger JSON file generated at: ${outputPath}`);
  }

  // const port = configService.get('PORT', 3000);
  await app.listen(port);

  console.log(`🚀 Application is running on: http://localhost:${port}`);
  if (configService.get('NODE_ENV') !== 'production') {
    console.log(`📚 Swagger documentation: http://localhost:${port}/api/docs`);
  }
}

// Only bootstrap if not running in Lambda
if (process.env.AWS_LAMBDA_FUNCTION_NAME === undefined) {
  bootstrap();
}