import fs from 'node:fs/promises'
import { createRequire } from 'node:module'

const localResolve = createRequire(import.meta.url).resolve

/**
 * Resolves the version string of an npm dependency installed in the based
 * directory.
 */
export async function getPackageVersion(pkg: string, base: string): Promise<string | null> {
  try {
    let packageJson = localResolve(`${pkg}/package.json`, { paths: [base] })
    let { version } = JSON.parse(await fs.readFile(packageJson, 'utf8'))
    return version
  } catch {
    return null
  }
}