import { resolve } from 'path'

import { copy, CopyOptions } from './utils/fs'
import { listPackagePaths, ListPackagesOptions } from './utils/npm'

export interface CopyNodeModulesOptions
  extends CopyOptions,
    ListPackagesOptions {
  basePath?: string
}

export function copyNodeModules(
  dest: string,
  options: CopyNodeModulesOptions = {}
): Promise<void> {
  if (!dest) {
    throw new TypeError('Missing destination directory argument.')
  }
  const basePath = options.basePath
    ? resolve(process.cwd(), options.basePath)
    : process.cwd()

  return listPackagePaths(options).then((pkgAbsPaths) => {
    return pkgAbsPaths.reduce(
      (carry, pkgAbsPath) =>
        carry.then(() => {
          return copy(
            pkgAbsPath,
            resolve(
              basePath,
              dest,
              pkgAbsPath.slice(pkgAbsPath.indexOf('node_modules'))
            )
          )
        }),
      Promise.resolve()
    )
  })
}