import { Resource } from '@opentelemetry/resources';
import { NodeTracerProvider } from '@opentelemetry/sdk-trace-node';
import { SemanticResourceAttributes } from '@opentelemetry/semantic-conventions';
import { JaegerExporter, ExporterConfig } from '@opentelemetry/exporter-jaeger';
import { SimpleSpanProcessor } from '@opentelemetry/sdk-trace-base';
import { TracerShim } from '@opentelemetry/shim-opentracing';
import { initGlobalTracer as openTracingInitGlobalTracer } from 'opentracing';
import { ExpressInstrumentation } from '@opentelemetry/instrumentation-express';
import { HttpInstrumentation } from '@opentelemetry/instrumentation-http';
import { ServerResponse } from 'http';

export const createShim = (serviceName: string, config?: ExporterConfig) => {
  const provider = new NodeTracerProvider({
    resource: new Resource({
      [SemanticResourceAttributes.SERVICE_NAME]: serviceName,
    }),
  });
  const exporter = new JaegerExporter(config);

  provider.addSpanProcessor(new SimpleSpanProcessor(exporter));

  if (process.env.ENABLE_HTTP_INSTRUMENTATION) {
    const expressInstrumentation = new ExpressInstrumentation();
    expressInstrumentation.setTracerProvider(provider);
    const httpInstrumentation = new HttpInstrumentation({
      responseHook: (span, response) => {
        if ((response as ServerResponse).setHeader) {
          const ctx = span.spanContext();
          (response as ServerResponse).setHeader('x-trace-id', ctx.traceId);
        }
      },
    });
    httpInstrumentation.setTracerProvider(provider);
  }

  // Initialize the OpenTelemetry APIs to use the NodeTracerProvider bindings
  provider.register();
  const tracer = provider.getTracer(
    process.env.TRACING_SERVICE_NAME || 'tempi-landing',
    process.env.NEXT_PUBLIC_IMAGE_TAG || '1.0.0',
  );

  return new TracerShim(tracer);
};
export const initGlobalTracer = (
  serviceName: string,
  config?: ExporterConfig,
) => {
  const shim = createShim(serviceName, config);
  openTracingInitGlobalTracer(shim);
};