import { execFileSync } from 'node:child_process';

import cookieParser from 'cookie-parser';
import { NestFactory } from '@nestjs/core';
import type { NestExpressApplication } from '@nestjs/platform-express';
import { apiEnvSchema, parseEnv } from '@dorfteich/shared';
import { Logger } from 'nestjs-pino';

import { AppModule } from './app.module';
import { AppConfig } from './config/app-config.service';

/**
 * Apply pending migrations before the application accepts traffic, so
 * self-hosters update by simply pulling a new image (ADR 0002). Prisma
 * serializes concurrent deploys with a database advisory lock.
 */
function runMigrations(): void {
  const prismaCli = require.resolve('prisma/build/index.js');
  execFileSync(process.execPath, [prismaCli, 'migrate', 'deploy'], { stdio: 'inherit' });
}

async function bootstrap(): Promise<void> {
  // Validate the environment before doing anything with it; this throws a
  // readable list of problems and prevents a half-started process.
  const env = parseEnv(apiEnvSchema, process.env);
  if (env.MIGRATE_ON_START) {
    runMigrations();
  }

  // bufferLogs holds early log lines until the pino logger is attached,
  // so even bootstrap errors come out as structured JSON.
  const app = await NestFactory.create<NestExpressApplication>(AppModule, { bufferLogs: true });
  app.useLogger(app.get(Logger));
  // One reverse-proxy hop (Caddy) in front of us: req.ip must reflect the
  // real client for rate limiting and audit logs.
  app.set('trust proxy', 1);
  app.use(cookieParser());
  // Base64-encoded Yjs page state (max 5 MiB, operations.md) inflates by
  // ~4/3; 8 MiB leaves headroom for the JSON envelope around it.
  app.useBodyParser('json', { limit: '8mb' });
  app.setGlobalPrefix('api/v1');
  app.enableShutdownHooks();

  const config = app.get(AppConfig);
  await app.listen(config.env.PORT);
}

void bootstrap();