async function downloadAndUnzipPackage()

in src/core/func-core-tools.ts [157:233]
68 lines of code
4 McCabe index (conditional complexity)

async function downloadAndUnzipPackage(release: CoreToolsRelease, dest: string) {
  const progressBar = new cliProgress.Bar(
    {
      format: "{bar} {percentage}% | ETA: {eta}s",
    },
    cliProgress.Presets.shades_classic,
  );
  try {
    const response = await fetch(release.url);
    const totalSize = Number(response.headers.get("content-length"));

    let downloadedSize = 0;
    let since = Date.now();
    progressBar.start(totalSize, downloadedSize);

    const bodyStream1 = response?.body?.pipe(new PassThrough());
    const bodyStream2 = response?.body?.pipe(new PassThrough());

    bodyStream2?.on("data", (chunk) => {
      downloadedSize += chunk.length;
      const now = Date.now();
      if (now - since > 100) {
        progressBar.update(downloadedSize);
        since = now;
      }
    });

    const downloadFilename = release.url.substring(release.url.lastIndexOf("/") + 1);
    const outputFile = path.join(dest, downloadFilename);
    const writableStream = fs.createWriteStream(outputFile);
    bodyStream2?.pipe(writableStream);

    const unzipPromise = new Promise((resolve, reject) => {
      const timeout = 30;
      let timer = setTimeout(() => {
        if (downloadedSize === 0) {
          writableStream.close();
          reject(new Error(`Download failed after ${timeout} seconds. Please check your network or retry.`));
        }
      }, timeout * 1000);

      writableStream.on("finish", () => {
        clearTimeout(timer);
        resolve(outputFile);
      });
      writableStream.on("error", (err) => {
        reject(err);
      });
    })
      .then(() => {
        const zip = new AdmZip(outputFile);
        zip.extractAllTo(dest, true);
        fs.unlinkSync(outputFile);
      })
      .catch((err) => {
        throw new Error(`Extract failed: ${err.message}`);
      });

    const hash = await new Promise((resolve) => {
      const hash = crypto.createHash("sha256");
      hash.setEncoding("hex");
      bodyStream1?.on("end", () => {
        hash.end();
        resolve(hash.read());
      });
      bodyStream1?.pipe(hash);
    });

    await unzipPromise;

    if (hash !== release.sha2) {
      throw new Error(`Downloaded Core Tools SHA2 mismatch: expected ${hash}, got ${release.sha2}`);
    }
  } finally {
    progressBar.stop();
  }
}