Drill 10: Why this way — Files and paths

import { readFile, writeFile, mkdir } from 'node:fs/promises'
import path from 'node:path'
import { fileURLToPath } from 'node:url'

const here = path.dirname(fileURLToPath(import.meta.url))
const dataDir = path.join(here, 'data')
const file = path.join(dataDir, 'scores.json')

type Score = {
  player: string
  score: number
}

async function loadScores(): Promise<Score[]> {
  try {
    const raw = await readFile(file, 'utf8')
    return JSON.parse(raw) as Score[]
  } catch (error) {
    const code = (error as NodeJS.ErrnoException).code
    if (code !== 'ENOENT') throw error
    return []
  }
}

async function saveScores(scores: Score[]): Promise<void> {
  await mkdir(dataDir, { recursive: true })
  await writeFile(file, JSON.stringify(scores, null, 2))
}