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/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 Middlewares
  app.use(helmet());
  app.enableCors({
    origin: [
      'http://localhost:3000',      // Local Swagger UI
      'http://localhost:5173',      // Local Frontend
      'https://editor.swagger.io',  // Swagger Editor
      'https://klc-admin.wdiprojects.com',
      'https://admin-uat.klc.betadelivery.com',
    ],
    methods: 'GET,HEAD,PUT,PATCH,POST,DELETE,OPTIONS',
    credentials: true,
  });

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

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

  // ✅ Global validation
  app.useGlobalPipes(
    new ValidationPipe({
      whitelist: true,
      forbidNonWhitelisted: true,
      transform: true,
      transformOptions: {
        enableImplicitConversion: true,
      },
    }),
  );

  // ✅ Swagger setup (only for local/dev)
  if (configService.get('NODE_ENV') !== 'production') {
    const swaggerConfig = new DocumentBuilder()
      .setTitle('Minglar API')
      .setDescription('NestJS Backend for Minglar with Lambda-ready endpoints')
      .setVersion(configService.get('API_VERSION') || '1.0.0')
      .addBearerAuth()
      .addServer(`${process.env.SERVER_URL || 'http://localhost:3000'}/`, 'Local Server')
      .build();

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

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

  // ✅ Start app (only for local or non-Lambda)
  const port = configService.get('PORT') || 3000;
  await app.listen(port);

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

// Only run bootstrap if not in AWS Lambda
if (!process.env.AWS_LAMBDA_FUNCTION_NAME) {
  bootstrap();
}