#!/usr/bin/env node

import { cpSync, existsSync, mkdtempSync, mkdirSync, readFileSync, rmSync } from 'node:fs';
import { createRequire } from 'node:module';
import { tmpdir } from 'node:os';
import { dirname, join, resolve } from 'node:path';
import { spawnSync } from 'node:child_process';
import { fileURLToPath } from 'node:url';

const require = createRequire(import.meta.url);
const root = resolve(dirname(fileURLToPath(import.meta.url)), '..');
const expectedVersion = JSON.parse(readFileSync(join(root, 'package.json'), 'utf8')).dependencies?.npm;
const npmPackagePath = require.resolve('npm/package.json');
const npmPackage = JSON.parse(readFileSync(npmPackagePath, 'utf8'));
const npmCli = join(dirname(npmPackagePath), 'bin', 'npm-cli.js');
const destination = join(root, 'build', 'publish-runtime');

if (npmPackage.version !== expectedVersion) {
  throw new Error(`Publish npm version mismatch: expected ${expectedVersion}, got ${npmPackage.version}`);
}
if (!npmPackage.bundleDependencies?.includes('proc-log')) {
  throw new Error('Publish npm package does not declare its runtime dependencies as bundled dependencies');
}

const temporaryRoot = mkdtempSync(join(tmpdir(), 'makelore-publish-runtime-'));
try {
  const packResult = spawnSync(process.execPath, [
    npmCli,
    'pack',
    dirname(npmPackagePath),
    '--ignore-scripts',
    '--json',
    '--pack-destination',
    temporaryRoot,
  ], { cwd: root, encoding: 'utf8', shell: false });
  if (packResult.status !== 0) {
    throw new Error(`Unable to pack publish npm runtime: ${packResult.stderr || packResult.stdout}`);
  }
  const packMetadata = JSON.parse(packResult.stdout);
  if (!Array.isArray(packMetadata) || packMetadata.length !== 1) {
    throw new Error('npm pack returned unexpected metadata');
  }
  const filename = packMetadata[0]?.filename;
  if (typeof filename !== 'string'
    || !/^[^/\\]+\.tgz$/.test(filename)
    || resolve(temporaryRoot, filename) !== join(temporaryRoot, filename)) {
    throw new Error(`npm pack returned an unsafe filename: ${JSON.stringify(filename)}`);
  }
  mkdirSync(join(temporaryRoot, 'runtime'), { recursive: true });
  await import('tar').then(({ x }) => x({
    file: join(temporaryRoot, filename),
    cwd: join(temporaryRoot, 'runtime'),
    strip: 1,
  }));

  const stagedRuntime = join(temporaryRoot, 'runtime');
  for (const dependency of npmPackage.bundleDependencies) {
    if (!existsSync(join(stagedRuntime, 'node_modules', ...dependency.split('/'), 'package.json'))) {
      throw new Error(`Packed npm runtime is missing bundled dependency ${dependency}`);
    }
  }

  rmSync(destination, { recursive: true, force: true });
  mkdirSync(dirname(destination), { recursive: true });
  cpSync(stagedRuntime, destination, { recursive: true });
} finally {
  rmSync(temporaryRoot, { recursive: true, force: true });
}

console.log(`Prepared self-contained npm ${npmPackage.version} runtime at ${destination}`);