// Downloads the standalone Piper release for this OS and the Swedish + English voices
// into <project>/piper/. Needs internet once; everything runs offline afterwards.
const fs = require("fs");
const os = require("os");
const path = require("path");
const { Readable } = require("stream");
const { pipeline } = require("stream/promises");
const { spawnSync } = require("child_process");

const PIPER_RELEASE_BASE = "https://github.com/rhasspy/piper/releases/download/2023.11.14-2";
const PIPER_ARCHIVES = {
  "linux-x64": "piper_linux_x86_64.tar.gz",
  "linux-arm64": "piper_linux_aarch64.tar.gz",
  "win32-x64": "piper_windows_amd64.zip",
  "darwin-x64": "piper_macos_x64.tar.gz",
  "darwin-arm64": "piper_macos_aarch64.tar.gz",
};
const VOICE_BASE = "https://huggingface.co/rhasspy/piper-voices/resolve/main";
const VOICES = [
  { name: "sv_SE-nst-medium", path: "sv/sv_SE/nst/medium" },
  { name: "en_US-lessac-medium", path: "en/en_US/lessac/medium" },
];

async function download(url, target) {
  const response = await fetch(url, { redirect: "follow" });
  if (!response.ok || !response.body) throw new Error(`Download failed (${response.status}): ${url}`);
  const partial = `${target}.part`;
  await pipeline(Readable.fromWeb(response.body), fs.createWriteStream(partial));
  fs.renameSync(partial, target);
}

async function installPiperBinary({ projectDir, log }) {
  const archive = PIPER_ARCHIVES[`${process.platform}-${process.arch}`];
  if (!archive) throw new Error(`No standalone Piper release for ${process.platform}-${process.arch}`);
  const tmpFile = path.join(os.tmpdir(), `racecore-${archive}`);
  log(`Downloading Piper (${archive})...`);
  await download(`${PIPER_RELEASE_BASE}/${archive}`, tmpFile);
  log("Unpacking Piper...");
  // tar ships with Linux, macOS and Windows 10+, and the Windows one also unpacks .zip.
  const result = spawnSync("tar", ["-xf", tmpFile, "-C", projectDir], { encoding: "utf8", windowsHide: true });
  fs.rmSync(tmpFile, { force: true });
  if (result.status !== 0) throw new Error(`Unpacking failed: ${result.stderr || result.error?.message || "tar error"}`);
}

async function installVoices({ voicesDir, log }) {
  fs.mkdirSync(voicesDir, { recursive: true });
  for (const voice of VOICES) {
    for (const file of [`${voice.name}.onnx.json`, `${voice.name}.onnx`]) {
      const target = path.join(voicesDir, file);
      if (fs.existsSync(target)) continue;
      log(`Downloading voice ${file}...`);
      await download(`${VOICE_BASE}/${voice.path}/${file}`, target);
    }
  }
}

// Skips anything already present, so re-running is cheap and safe.
async function installAll({ projectDir, hasBinary, log = () => {} }) {
  if (!hasBinary) await installPiperBinary({ projectDir, log });
  else log("Piper already installed.");
  await installVoices({ voicesDir: path.join(projectDir, "piper", "voices"), log });
  log("Done.");
}

module.exports = { installAll, installVoices, installPiperBinary, VOICES, PIPER_ARCHIVES };