import { test } from "node:test";
import assert from "node:assert/strict";
import { classifyFfmpegProbe } from "./ffmpegStreamClassify";

// Run with:
//   pnpm --filter yt-dlp-transcript-common exec tsx --test ytdlp/ffmpegStreamClassify.test.ts
//
// The ffmpeg probe-result classifier. Pure: an exit code and a stderr string
// in, a verdict out. (These lived in the editor's e2e suite as
// audio-check-classifier.spec.ts, booting a dev server they never used.)

const DECODER_ERROR =
  "[aist#0:1/aac @ 0x2] [dec:aac @ 0x3] Error submitting packet to decoder: Invalid data found when processing input\n";
const PARTIAL_FILE =
  "[in#0/mov,mp4,m4a,3gp,3g2,mj2 @ 0x4] stream 1, offset 0x1626f8a: partial file\n";

test("exit 0 with empty stderr → clean", () => {
  assert.equal(classifyFfmpegProbe(0, ""), "clean");
  assert.equal(classifyFfmpegProbe(0, "\n  \t\n"), "clean");
});

test("exit 0 with 'partial file' stderr → partial", () => {
  assert.equal(
    classifyFfmpegProbe(
      0,
      "[in#0/mov,mp4,m4a,3gp,3g2,mj2 @ 0x1234] stream 1, offset 0x10483924: partial file\n",
    ),
    "partial",
  );
});

test("exit 0 with many decoder errors and no 'partial file' → malformed", () => {
  // ffmpeg can exit 0 even when the av_codec layer rejects hundreds of
  // packets — the encoder keeps producing output from whatever decoded. A wall
  // of "Error submitting packet to decoder" lines without a "partial file"
  // demuxer warning is mid-stream corruption, not a clean truncation.
  const aacStorm = Array.from(
    { length: 50 },
    (_, i) =>
      `[aac @ 0x1] channel element ${i % 3}.${i % 16} is not allocated\n` +
      DECODER_ERROR,
  ).join("");
  assert.equal(classifyFfmpegProbe(0, aacStorm), "malformed");
});

test("exit 0 with many decoder errors AND 'partial file' → malformed (corruption wins over truncation)", () => {
  const stormPlusPartial =
    Array.from({ length: 50 }, () => DECODER_ERROR).join("") + PARTIAL_FILE;
  assert.equal(classifyFfmpegProbe(0, stormPlusPartial), "malformed");
});

test("exit 0 with a small tail of decoder errors AND 'partial file' → partial", () => {
  // Truncated containers often emit a couple of trailing decoder errors as the
  // encoder eats the last partial packets. Below the threshold the file is
  // still classifiable as partial.
  const tail = DECODER_ERROR + DECODER_ERROR + PARTIAL_FILE;
  assert.equal(classifyFfmpegProbe(0, tail), "partial");
});

test("non-zero exit → malformed (regardless of stderr)", () => {
  assert.equal(
    classifyFfmpegProbe(
      1,
      "[aac @ 0x1] Sample rate index in program config element does not match the sample rate index configured by the container.\n",
    ),
    "malformed",
  );
  assert.equal(classifyFfmpegProbe(2, ""), "malformed");
  assert.equal(classifyFfmpegProbe(null, "killed by signal"), "malformed");
});