// RUM issue capture: forwards client-side errors into the OpenTelemetry RUM
// pipeline (window.OtelRUM is loaded from otel.k6n.net in index.html).

export function captureRumIssue(
  message: string,
  severity = 'ERROR',
  extra: Record<string, unknown> = {},
): void {
  const rum = (globalThis as Record<string, any>).OtelRUM?.last;
  if (!rum || typeof rum.captureMessage !== 'function') return;
  try {
    rum.captureMessage(message, severity, extra);
  } catch (err) {
    console.warn('RUM capture failed', err);
  }
}

export function installGlobalErrorHandlers(): void {
  window.addEventListener('error', (event) => {
    captureRumIssue(event.message || 'Unhandled browser error', 'ERROR', {
      source: event.filename,
      line: event.lineno,
      column: event.colno,
    });
  });

  window.addEventListener('unhandledrejection', (event) => {
    const reason = (event as PromiseRejectionEvent).reason;
    captureRumIssue(`Unhandled promise rejection: ${reason?.message || reason || 'unknown error'}`, 'ERROR', {
      name: reason?.name,
      stack: reason?.stack,
    });
  });
}

/** Trace headers for fetches so server spans link to the browser trace. */
export function rumTraceHeaders(): Record<string, string> {
  const rum = (window as Record<string, any>).rum;
  if (rum && typeof rum.traceHeaders === 'function') return rum.traceHeaders() || {};
  return {};
}