/**
 * Serves the Bandcamp release the native player plays, resolved from its page
 * when playback starts. On any failure the player falls back to the embed.
 *
 * - `GET /api/bandcamp/tracks?url=&force=` — public. Answers the page's
 *   tracks and their stream URLs; `force=1` skips the server's cache.
 *
 * @module
 */

import { Router } from "@oak/oak";
import type { APIResponse } from "../../shared/api.ts";
import { resolveBandcamp } from "../remote/bandcamp-streams.ts";
import type { Tralbum } from "../../shared/player.ts";

/**
 * Mounted by `api/main.ts` behind the error, Open Graph and CORS middleware.
 * An `APIException` thrown by a handler becomes the JSON error response there.
 */
const bandcampRouter: Router = new Router();

// Public: it reads a public page and answers the URLs that page gives any
// visitor.
bandcampRouter.get("/api/bandcamp/tracks", async (ctx) => {
  const url = ctx.request.url.searchParams.get("url") ?? "";
  const force = ctx.request.url.searchParams.get("force") === "1";

  const responseBody: APIResponse<Tralbum> = {
    success: true,
    data: await resolveBandcamp(url, { force }),
  };

  // Not in a shared cache: the signed URLs belong to one page fetch. An hour
  // is well inside their 24 hours.
  ctx.response.headers.set("Cache-Control", "private, max-age=3600");
  ctx.response.body = responseBody;
});

export default bandcampRouter;