import { createReadStream, createWriteStream } from 'node:fs';
import { constants as zlibConstants, createBrotliCompress, createGzip } from 'node:zlib';

export async function createCompressedVariants(filePath: string): Promise<void> {
  await Promise.all([
    compress(filePath, '.br', () =>
      createBrotliCompress({ params: { [zlibConstants.BROTLI_PARAM_QUALITY]: 11 } }),
    ),
    compress(filePath, '.gz', () => createGzip({ level: zlibConstants.Z_BEST_COMPRESSION })),
  ]);
}

async function compress(
  source: string,
  extension: string,
  factory: () => NodeJS.ReadWriteStream,
): Promise<void> {
  return new Promise((resolve, reject) => {
    const destination = `${source}${extension}`;
    const readStream = createReadStream(source);
    const writeStream = createWriteStream(destination);
    const compressor = factory();

    readStream.on('error', reject);
    writeStream.on('error', reject);
    compressor.on('error', reject);
    writeStream.on('close', resolve);

    readStream.pipe(compressor).pipe(writeStream);
  });
}