import { mkdir, readFile, writeFile, readdir, copyFile } from 'node:fs/promises';
import path from 'node:path';
import { createHash } from 'node:crypto';
import { verifyMediaDistribution } from './verify-media-distribution.mjs';

const destination = 'apps/web/public/vendor/ffmpeg-0.12.10';
await mkdir(destination, { recursive: true });
for (const name of await readdir('node_modules/@ffmpeg/ffmpeg/dist/esm')) {
  if (name.endsWith('.js')) await copyFile(path.join('node_modules/@ffmpeg/ffmpeg/dist/esm', name), path.join(destination, name));
}
await copyFile('node_modules/@ffmpeg/core/dist/esm/ffmpeg-core.js', path.join(destination, 'ffmpeg-core.js'));
const wasm = await readFile('node_modules/@ffmpeg/core/dist/esm/ffmpeg-core.wasm');
const parts = [];
for (let offset = 0, index = 0; offset < wasm.length; offset += 12 * 1024 * 1024, index++) {
  const bytes = wasm.subarray(offset, offset + 12 * 1024 * 1024);
  const file = `core-${index}.bin`;
  await writeFile(path.join(destination, file), bytes);
  parts.push({ file, bytes: bytes.length, sha256: createHash('sha256').update(bytes).digest('hex') });
}
await writeFile(path.join(destination, 'manifest.json'), JSON.stringify({ bytes: wasm.length, parts }));
console.log(`Prepared FFmpeg: ${wasm.length} bytes in ${parts.length} parts; largest ${Math.max(...parts.map(p => p.bytes))} bytes.`);
for (const file of ['prepare-media-assets.mjs', 'prepare-media-sources.mjs', 'verify-media-distribution.mjs']) await copyFile(`scripts/${file}`, path.join(destination, `${file}.txt`));
if (process.env.APP_ENV === 'production') await verifyMediaDistribution(destination);