import path from "node:path";
import { readFile } from "node:fs/promises";
import { getPaths } from "yt-dlp-transcript-common/lib/paths";

export const dynamic = "force-dynamic";

// Serves built export artifacts (stats/summaries/transcripts JSON) from
// exportPublicDir so the editor's charts authoring tab can preview real data.
// The static viewer serves these as plain files; the editor proxies them.
export async function GET(
  _request: Request,
  { params }: { params: Promise<{ path: string[] }> },
) {
  const { path: segments } = await params;
  // Reject path traversal / absolute escapes.
  if (segments.some((s) => s === ".." || s.includes("\0") || path.isAbsolute(s))) {
    return new Response("Bad request", { status: 400 });
  }
  const root = getPaths().exportPublicDir;
  const target = path.join(root, ...segments);
  if (!target.startsWith(root + path.sep)) {
    return new Response("Bad request", { status: 400 });
  }
  try {
    const body = await readFile(target);
    const type = target.endsWith(".json")
      ? "application/json"
      : "application/octet-stream";
    return new Response(body, {
      headers: { "content-type": type, "cache-control": "no-store" },
    });
  } catch {
    return new Response("Not found", { status: 404 });
  }
}