import { createRouter } from '../../create-router';
import { getMusicServerUrl } from './sidecar-server';

// Thin reverse-proxy for /api/music/*. Auth is handled upstream by userMiddleware (this router mounts
// under the protected /api tree, so the media `?token=` path works). Everything else — path resolution,
// byte-range streaming, ffprobe duration — is done by the officer-music sidecar's audio server. We only
// forward the subpath + query + Range and stream the response back.

export const musicRouter = createRouter();

const PREFIX = '/api/music';

musicRouter.all('/*', async (ctx) => {
  const baseUrl = getMusicServerUrl();
  if (!baseUrl) return ctx.text('Music sidecar not available', 503);

  const url = new URL(ctx.req.url);
  const subpath = url.pathname.slice(PREFIX.length) || '/';
  const target = `${baseUrl}${subpath}${url.search}`;

  const range = ctx.req.header('range');
  let upstream: Response;
  try {
    upstream = await fetch(target, {
      method: ctx.req.method,
      headers: range ? { Range: range } : {},
    });
  } catch (err) {
    console.error('[music] proxy fetch failed', { target, error: String(err) });
    return ctx.text('Music sidecar unreachable', 502);
  }

  // Pass status + headers through and stream the body (206/Content-Range/X-Audio-Duration included).
  return new Response(upstream.body, { status: upstream.status, headers: new Headers(upstream.headers) });
});