import {build} from 'esbuild';
import {createHash} from 'node:crypto';
import {createWriteStream} from 'node:fs';
import {cp, mkdir, readdir, rm, stat, rename, unlink} from 'node:fs/promises';
import {join, resolve} from 'node:path';
import {Readable, Transform} from 'node:stream';
import {pipeline} from 'node:stream/promises';

const root = process.cwd();
const publicRoot = join(root, 'public');
const assetRoot = join(publicRoot, 'tts', 'piper-wasm-v1');
const onnxSource = join(root, 'node_modules', 'onnxruntime-web', 'dist');
const piperSource = join(root, 'node_modules', '@diffusionstudio', 'piper-wasm', 'build');
const piperWasm = join(piperSource, 'piper_phonemize.wasm');
const piperData = join(piperSource, 'piper_phonemize.data');

const voiceRevision = 'c10ece1aade47bb51c153c893d14e5bf8e5b7117';
const voiceRepository = 'https://huggingface.co/rhasspy/piper-voices/resolve';
const voiceFiles = [
  {path: 'sv/sv_SE/alma/medium/sv_SE-alma-medium.onnx', size: 63434611, sha256: 'f75455eb6afeb1db9e2905d5bd7e4115afcd3710e0d399b6a40981766d32fedc'},
  {path: 'sv/sv_SE/alma/medium/sv_SE-alma-medium.onnx.json', size: 6059, gitBlobSha1: '7eaf3ef20af4a74e9cee9d29b98de3d9fcec0bdc'},
  {path: 'sv/sv_SE/lisa/medium/sv_SE-lisa-medium.onnx', size: 63511038, sha256: '94cae912b31d6e9140d3f5160f1815951588600c7a9e43d539ba1e81a110d131'},
  {path: 'sv/sv_SE/lisa/medium/sv_SE-lisa-medium.onnx.json', size: 7239, gitBlobSha1: 'b2b5fb0f8af2aae4ddfb81eaa7709c6b8faa412b'},
  {path: 'sv/sv_SE/nst/medium/sv_SE-nst-medium.onnx', size: 63104526, sha256: 'df011f56825a59dd1efc080c38a65a1ef70407e60f63050e9246f43a3d7e471e'},
  {path: 'sv/sv_SE/nst/medium/sv_SE-nst-medium.onnx.json', size: 4157, gitBlobSha1: '9766b9769436046a610a505fda925032e12a66b3'},
];

async function downloadVoiceFile(file) {
  const destination = join(assetRoot, 'voices', file.path);
  const temporary = `${destination}.part`;
  await mkdir(join(destination, '..'), {recursive: true});
  const response = await fetch(`${voiceRepository}/${voiceRevision}/${file.path}`);
  if (!response.ok || !response.body) {
    throw new Error(`Unable to download Piper voice asset ${file.path}: HTTP ${response.status}`);
  }
  const sha256 = createHash('sha256');
  const sha1 = createHash('sha1').update(Buffer.from(`blob ${file.size}\0`));
  let size = 0;
  const verifyAndPassThrough = new Transform({
    transform(chunk, _encoding, callback) {
      size += chunk.length;
      sha256.update(chunk);
      sha1.update(chunk);
      callback(null, chunk);
    },
  });
  try {
    await pipeline(Readable.fromWeb(response.body), verifyAndPassThrough, createWriteStream(temporary));
    const actualSha1 = sha1.digest('hex');
    if (size !== file.size || (file.sha256 && sha256.digest('hex') !== file.sha256) ||
        (file.gitBlobSha1 && actualSha1 !== file.gitBlobSha1)) {
      throw new Error(`Piper voice asset integrity check failed for ${file.path} (${size} bytes)`);
    }
    await rename(temporary, destination);
  } catch (error) {
    await unlink(temporary).catch(() => {});
    throw error;
  }
}

await rm(assetRoot, {recursive: true, force: true});
await mkdir(join(assetRoot, 'onnx'), {recursive: true});
await mkdir(join(assetRoot, 'piper'), {recursive: true});
for (const file of voiceFiles) await downloadVoiceFile(file);
await cp(join(root, 'PIPER_VOICE_NOTICES.txt'), join(assetRoot, 'voices', 'ATTRIBUTION.txt'));

const onnxRuntimeFiles = (await readdir(onnxSource))
  .filter(name => name.endsWith('.wasm') || name.endsWith('.mjs'));
const requiredOnnxRuntimeFiles = [
  'ort-wasm-simd-threaded.wasm',
  'ort-wasm-simd-threaded.mjs',
];
for (const file of requiredOnnxRuntimeFiles) {
  if (!onnxRuntimeFiles.includes(file)) throw new Error(`Missing ONNX Runtime asset: ${file}`);
}
for (const file of onnxRuntimeFiles) {
  await cp(join(onnxSource, file), join(assetRoot, 'onnx', file));
}
for (const file of [piperWasm, piperData]) {
  const fileStat = await stat(file).catch(() => null);
  if (!fileStat?.isFile() || fileStat.size === 0) throw new Error(`Missing Piper WebAssembly asset: ${file}`);
  await cp(file, join(assetRoot, 'piper', file.split('/').at(-1)));
}

await build({
  entryPoints: [resolve(root, 'piper-runtime.js')],
  outfile: join(publicRoot, 'piper-runtime.js'),
  bundle: true,
  format: 'iife',
  platform: 'browser',
  target: ['es2022'],
  external: ['fs', 'path'],
  sourcemap: false,
  legalComments: 'none',
});

await build({
  entryPoints: [resolve(root, 'piper-worker.js')],
  outfile: join(assetRoot, 'piper-worker.js'),
  bundle: true,
  format: 'iife',
  platform: 'browser',
  target: ['es2022'],
  external: ['fs', 'path'],
  sourcemap: false,
  legalComments: 'none',
});

for (const file of voiceFiles) {
  const downloaded = join(assetRoot, 'voices', file.path);
  if ((await stat(downloaded)).size !== file.size) throw new Error(`Missing Piper voice asset: ${downloaded}`);
}
const workerBundle = await (await import('node:fs/promises')).readFile(join(assetRoot, 'piper-worker.js'), 'utf8');
if (!workerBundle.includes('https://huggingface.co/diffusionstudio/piper-voices/resolve/main/') ||
    !workerBundle.includes('/tts/piper-wasm-v1/voices/') ||
    !workerBundle.includes('/tts/piper-wasm-v1/onnx/')) {
  throw new Error('The Piper worker is missing its same-origin model download route.');
}

console.log(`Piper browser assets prepared at ${assetRoot}`);