import 'reflect-metadata';
import { ValidationPipe } from '@nestjs/common';
import { NestFactory } from '@nestjs/core';
import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
import { AppModule } from './app.module';
import { createRequestContextMiddleware } from './common/request-context.middleware';
import { MetricsService } from './common/metrics.service';

function requireEnv(name: string): string {
  const value = process.env[name];
  if (!value || value.trim() === '') {
    throw new Error(`Missing required env: ${name}`);
  }
  return value;
}

function validateEnv(): void {
  requireEnv('DB_HOST');
  requireEnv('DB_PORT');
  requireEnv('DB_USER');
  requireEnv('DB_PASSWORD');
  requireEnv('DB_NAME');
  requireEnv('CENTER_SHARED_SECRET');
  requireEnv('JWT_ACCESS_SECRET');
  requireEnv('JWT_REFRESH_SECRET');
}

async function bootstrap() {
  validateEnv();

  const app = await NestFactory.create(AppModule);
  app.setGlobalPrefix('api');
  const metrics = app.get(MetricsService);
  app.use(createRequestContextMiddleware('center', metrics));
  app.useGlobalPipes(
    new ValidationPipe({
      whitelist: true,
      forbidNonWhitelisted: true,
      transform: true,
    }),
  );

  const swaggerConfig = new DocumentBuilder()
    .setTitle('Fabric Backend Center API')
    .setDescription('Identity Hub APIs for Fabric')
    .setVersion('1.0.0')
    .build();
  const swaggerDoc = SwaggerModule.createDocument(app, swaggerConfig);
  SwaggerModule.setup('docs', app, swaggerDoc);

  const port = process.env.PORT ? Number(process.env.PORT) : 7001;
  await app.listen(port);
  console.log(`Fabric.Backend.Center listening on :${port}`);
}

void bootstrap();