import path from 'path'
import fse from 'fs-extra'
import { Ref, Lerna, Pkg, Result } from './types.js'

export async function readJson<T>(dir: string, file: string) {
  try {
    return (await fse.readJson(path.join(dir, file))) as T
  } catch (err) {
    if (err.code !== 'ENOENT') {
      throw err
    }
  }
}

export function readJsonSync<T>(dir: string, file: string) {
  try {
    return fse.readJSONSync(path.join(dir, file)) as T
  } catch (err) {
    if (err.code !== 'ENOENT') {
      throw err
    }
  }
}

export function yarnlize(
  dir: string,
  ref: Ref,
  pkg?: Pkg,
): Result<'yarn' | 'bolt'> | undefined {
  if (pkg) {
    if (ref.pkg == null) {
      ref.pkg = dir
    }

    if (pkg.workspaces || pkg.bolt) {
      return { dir, client: pkg.bolt ? 'bolt' : 'yarn' }
    }
  }
}

export function lernalize(
  dir: string,
  lerna?: Lerna,
): Result<'lerna'> | undefined {
  // https://lerna.js.org/docs/api-reference/configuration
  if (lerna) {
    if (lerna.useWorkspaces || lerna.packages) {
      return { client: 'lerna', dir }
    }
  }
}

export function pnpmlize(
  dir: string,
  exists: boolean,
): Result<'pnpm'> | undefined {
  if (exists) {
    return { client: 'pnpm', dir }
  }
}

export function rollup(result: Result | undefined, ref: Ref) {
  if (ref.pkg == null) {
    throw new Error(
      `No package.json could be found upwards from the directory ${ref.cwd}`,
    )
  }

  return result || { client: 'root', dir: ref.pkg }
}