import { NodeSDK } from '@opentelemetry/sdk-node';
import { getNodeAutoInstrumentations } from '@opentelemetry/auto-instrumentations-node';
import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-http';
import { OTLPMetricExporter } from '@opentelemetry/exporter-metrics-otlp-http';
import { PeriodicExportingMetricReader } from '@opentelemetry/sdk-metrics';
import { resourceFromAttributes } from '@opentelemetry/resources';
import { ATTR_SERVICE_NAME, ATTR_SERVICE_VERSION } from '@opentelemetry/semantic-conventions';

const otlpEndpoint = process.env['OTEL_EXPORTER_OTLP_ENDPOINT'] ?? 'http://localhost:4318';

const sdk = new NodeSDK({
  resource: resourceFromAttributes({
    [ATTR_SERVICE_NAME]: process.env['OTEL_SERVICE_NAME'] ?? 'mosaic-gateway',
    [ATTR_SERVICE_VERSION]: '0.0.0',
  }),
  traceExporter: new OTLPTraceExporter({
    url: `${otlpEndpoint}/v1/traces`,
  }),
  metricReader: new PeriodicExportingMetricReader({
    exporter: new OTLPMetricExporter({
      url: `${otlpEndpoint}/v1/metrics`,
    }),
    exportIntervalMillis: 15_000,
  }),
  instrumentations: [
    getNodeAutoInstrumentations({
      '@opentelemetry/instrumentation-fs': { enabled: false },
      '@opentelemetry/instrumentation-dns': { enabled: false },
    }),
  ],
});

sdk.start();

process.on('SIGTERM', () => {
  sdk
    .shutdown()
    .then(() => process.exit(0))
    .catch(() => process.exit(1));
});

export { sdk };