import { Logger } from '@nestjs/common';
import { NestFactory } from '@nestjs/core';
import { NestExpressApplication } from '@nestjs/platform-express';
import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
import cookieParser from 'cookie-parser';
import helmet from 'helmet';
import type { NextFunction, Request, Response } from 'express';
import { AppModule } from './app.module';
import { AllExceptionsFilter } from './common/filters/all-exceptions.filter';
import { loadConfiguration } from './config/config.tokens';

/**
 * Bootstrap der Management-API:
 * - Security-Header (Helmet), Trust-Proxy für korrekte IPs
 * - OpenAPI/Swagger unter /api/docs
 * - Strukturierte Fehlerbehandlung
 * Hinweis: Validierung erfolgt über Zod (ZodValidationPipe),
 * nicht über den NestJS-ValidationPipe (class-validator).
 */
async function bootstrap(): Promise<void> {
  const config = loadConfiguration();
  const logger = new Logger('Bootstrap');

  const app = await NestFactory.create<NestExpressApplication>(AppModule, {
    logger: config.nodeEnv === 'production' ? ['log', 'warn', 'error'] : ['log', 'warn', 'error', 'debug'],
  });

  app.use(helmet());
  app.use(cookieParser());
  app.use('/api', (_request: Request, response: Response, next: NextFunction) => {
    response.setHeader('Cache-Control', 'no-store');
    next();
  });

  if (config.security.behindProxy) {
    app.set('trust proxy', 1);
  }

  app.useGlobalFilters(new AllExceptionsFilter());

  const swaggerConfig = new DocumentBuilder()
    .setTitle('MPM Management API')
    .setDescription('Zentrale Management-API der MPM-Plattform (Auth, RBAC, Health)')
    .setVersion('0.1.0')
    .addCookieAuth('mpm_session')
    .build();
  const document = SwaggerModule.createDocument(app, swaggerConfig);
  SwaggerModule.setup('api/docs', app, document);

  await app.listen(config.port, '0.0.0.0');
  logger.log(`Management-Backend läuft auf Port ${config.port}`);
}

void bootstrap();