import test from "node:test";
import assert from "node:assert/strict";
import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
import os from "node:os";
import path from "node:path";

// Run with:
//   pnpm -C editor exec tsx --test "app/api/channels/*/videos/*/files/*/route.test.ts"
//
// The media file route's byte ranges, in-process. The ABORT regression
// (`Controller is already closed` when a scrubbing browser cancels range
// requests) stays e2e in media-file-abort.spec.ts: a burst of cancelled
// bodies run against this handler in-process passes even with the naive
// wrapper that caused it — the race is in the server's response pipeline, not
// in the handler — so only the HTTP round trip is a real test of it. The guard
// itself is unit-tested in common/lib/safeStreamController.test.ts.

const ROOT = await mkdtemp(path.join(os.tmpdir(), "media-file-route-"));
const CORPUS = path.join(ROOT, "transcripts");
const VIDEO_DIR = path.join(CORPUS, "channels", "chan", "data", "vidA");
await mkdir(VIDEO_DIR, { recursive: true });
await writeFile(path.join(VIDEO_DIR, "audio.m4a"), Buffer.alloc(1024 * 1024, 7));
// Set before anything that caches getPaths() is first imported.
process.env.TRANSCRIPTS_DIR = CORPUS;
process.env.SETTINGS_FILE = path.join(ROOT, "settings.json");
const { GET } = await import("./route");
test.after(() => rm(ROOT, { recursive: true, force: true }));

function get(range?: string) {
  return GET(
    new Request("http://localhost/api/channels/chan/videos/vidA/files/audio.m4a", {
      headers: range ? { range } : {},
    }),
    { params: Promise.resolve({ slug: "chan", id: "vidA", name: "audio.m4a" }) },
  );
}

test("a range request is a 206 with the bytes asked for", async () => {
  const res = await get("bytes=100-4195");
  assert.equal(res.status, 206);
  assert.equal(res.headers.get("content-range"), "bytes 100-4195/1048576");
  const body = Buffer.from(await res.arrayBuffer());
  assert.equal(body.length, 4096);
});

test("a suffix range is the last N bytes; no or a bad range is the whole file", async () => {
  const suffix = await get("bytes=-100");
  assert.equal(suffix.status, 206);
  assert.equal(suffix.headers.get("content-range"), "bytes 1048476-1048575/1048576");
  assert.equal((await suffix.arrayBuffer()).byteLength, 100);
  for (const range of [undefined, "bytes=5-2", "bytes=0-9999999", "lines=1-2"]) {
    const res = await get(range);
    assert.equal(res.status, 200, String(range));
    assert.equal(res.headers.get("content-length"), "1048576");
    await res.body!.cancel();
  }
});

test("a path that leaves the video dir is refused; a missing file is a 404", async () => {
  const bad = await GET(new Request("http://localhost/x"), {
    params: Promise.resolve({ slug: "chan", id: "..%2F..", name: "audio.m4a" }),
  });
  assert.equal(bad.status, 400);
  const missing = await GET(new Request("http://localhost/x"), {
    params: Promise.resolve({ slug: "chan", id: "vidA", name: "nope.m4a" }),
  });
  assert.equal(missing.status, 404);
});