const config = require('../config/config');
const logger = require('../util/logger');
const migrate = require('../maintenance/migrate');
const instrumentConfig = require('../config/instrumentConfig');
const { createHttpServer } = require('../http/index');
const {
  buildConnectors,
  attachConnectorHandlers,
  startConnectors,
  stopConnectors
} = require('./connectors');
const { startWorkers, stopWorkers } = require('./workers');

async function start() {
  instrumentConfig.validateAndLoadInstrumentConfigs();
  await migrate();
  await instrumentConfig.init();

  const connectors = buildConnectors();
  if (!connectors.length) {
    logger.warn('no enabled connectors configured, ingestion listeners are disabled');
  }

  attachConnectorHandlers(connectors);
  await startConnectors(connectors);
  await startWorkers();

  const app = createHttpServer(connectors);
  const server = app.listen(config.healthPort, () => {
    logger.info({ port: config.healthPort }, 'health server ready');
  });

  async function shutdown() {
    await stopWorkers();
    await stopConnectors(connectors);
    if (server) {
      await new Promise((resolve) => server.close(resolve));
    }
  }

  return { connectors, server, shutdown };
}

module.exports = { start };