feat: generate-play can structurize playground and preserve changes (type-challenges#27506)

Author: jazelly

.gitignore

@@ -5,3 +5,4 @@ dist
 *.log
 *.local
 playground/
+.playgroundcache

README.md

@@ -119,6 +119,16 @@ pnpm generate
 
 It will prompt you to select the desired language, then you can find the generated challenges in the `./playground` folder.
 
+Later if you want to update playground while keeping your changes:
+
+```bash
+pnpm generate --keep-changes
+```
+OR
+```bash
+pnpm generate -K
+```
+
 ## Thanks
 
 This project was born from solving real-world types problem with [@hardfist](https://github.com/hardfist) and [@MeCKodo](https://github.com/MeCKodo). And great thanks to [@sinoon](https://github.com/sinoon) who contributed a lot while giving early feedback on this project.

scripts/generate-play.ts

@@ -1,21 +1,109 @@
 import path from 'path'
 import { argv } from 'process'
+import crypto from 'crypto'
 import fs from 'fs-extra'
 import c from 'picocolors'
 import prompts from 'prompts'
 import { formatToCode } from './actions/utils/formatToCode'
 import { loadQuizes, resolveInfo } from './loader'
-import { defaultLocale, supportedLocales } from './locales'
+import { supportedLocales } from './locales'
 import { getQuestionFullName } from './actions/issue-pr'
 import type { QuizMetaInfo } from './types'
 
+type Snapshot = Record<string, string>
+
+function calculateFileHash(filePathFull: string): Promise<string> {
+  return new Promise((resolve, reject) => {
+    const hash = crypto.createHash('sha1')
+    const fileStream = fs.createReadStream(filePathFull)
+
+    fileStream.on('data', (data) => {
+      hash.update(data)
+    })
+
+    fileStream.on('end', () => {
+      hash.update(filePathFull)
+      resolve(hash.digest('hex'))
+    })
+
+    fileStream.on('error', (err) => {
+      reject(err)
+    })
+  })
+}
+
+async function takeSnapshot(quizesPath: string) {
+  let snapshot: Snapshot = {}
+
+  const files = fs.readdirSync(quizesPath)
+
+  for (const file of files) {
+    // Might be a file, or a folder
+    const fPath = path.join(quizesPath, file)
+    const fStats = fs.statSync(fPath)
+
+    if (fStats.isDirectory()) {
+      snapshot = {
+        ...snapshot,
+        ...(await takeSnapshot(fPath)),
+      }
+    }
+    else {
+      snapshot[file] = await calculateFileHash(fPath)
+    }
+  }
+
+  return snapshot
+}
+
+function readPlaygroundCache(playgroundCachePath: string): Snapshot {
+  if (!fs.existsSync(playgroundCachePath))
+    return {}
+
+  try {
+    const rawCacheContent = fs.readFileSync(playgroundCachePath)
+    return JSON.parse(rawCacheContent.toString())
+  }
+  catch (err) {
+    console.log(c.red('Playground cache corrupted. '
+      + 'Cannot generate playground without keeping your changes intact'))
+    console.log(c.cyan('Please ensure you have run this: "pnpm generate"'))
+    process.exit(1)
+  }
+}
+
+function calculateOverridableFiles(cache: Snapshot, snapshot: Snapshot) {
+  const result: Snapshot = {}
+
+  for (const quizName in snapshot) {
+    if (snapshot[quizName] === cache[quizName])
+      result[quizName] = snapshot[quizName]
+  }
+
+  return result
+}
+
 async function generatePlayground() {
-  const quizesPath = path.join(__dirname, '../playground')
+  const playgroundPath = path.join(__dirname, '../playground')
+  const playgroundCachePath = path.join(__dirname, '../.playgroundcache')
+
   let locale = supportedLocales.find(locale => locale === argv[2])!
 
-  console.log(c.bold(c.cyan('Generateing local playground...\n')))
+  console.log(c.bold(c.cyan('Generating local playground...\n')))
+
+  let overridableFiles: Snapshot = {}
+  let keepChanges = false
+  const currentPlaygroundCache = readPlaygroundCache(playgroundCachePath)
 
-  if (fs.existsSync(quizesPath)) {
+  if (argv.length === 3 && (argv[2] === '--keep-changes' || argv[2] === '-K')) {
+    console.log(c.bold(c.cyan('We will keep your chanegs while generating.\n')))
+    keepChanges = true
+
+    const playgroundSnapshot = await takeSnapshot(playgroundPath)
+
+    overridableFiles = calculateOverridableFiles(currentPlaygroundCache, playgroundSnapshot)
+  }
+  else if (fs.existsSync(playgroundPath)) {
     const result = await prompts([{
       name: 'confirm',
       type: 'confirm',
@@ -41,20 +129,38 @@ async function generatePlayground() {
     locale = result.locale
   }
 
-  await fs.remove(quizesPath)
-  await fs.ensureDir(quizesPath)
+  if (!keepChanges) {
+    await fs.remove(playgroundPath)
+    await fs.ensureDir(playgroundPath)
+  }
 
   const quizes = await loadQuizes()
+  const incomingQuizesCache: Snapshot = {}
+
   for (const quiz of quizes) {
     const { difficulty, title } = resolveInfo(quiz, locale) as QuizMetaInfo & { difficulty: string }
     const code = formatToCode(quiz, locale)
-    const filepath = path.join(quizesPath, `${getQuestionFullName(quiz.no, difficulty, title)}.ts`)
 
-    await fs.writeFile(filepath, code, 'utf-8')
+    const quizesPathByDifficulty = path.join(playgroundPath, difficulty)
+
+    const quizFileName = `${getQuestionFullName(quiz.no, difficulty, title)}.ts`
+    const quizPathFull = path.join(quizesPathByDifficulty, quizFileName)
+
+    if (!keepChanges || overridableFiles[quizFileName]) {
+      if (!fs.existsSync(quizesPathByDifficulty))
+        fs.mkdirSync(quizesPathByDifficulty)
+      await fs.writeFile(quizPathFull, code, 'utf-8')
+      incomingQuizesCache[quizFileName] = await calculateFileHash(quizPathFull)
+    }
   }
 
+  fs.writeFile(playgroundCachePath, JSON.stringify({
+    ...currentPlaygroundCache,
+    ...incomingQuizesCache,
+  }))
+
   console.log()
-  console.log(c.bold(c.green('Local playground generated at: ')) + c.dim(quizesPath))
+  console.log(c.bold(c.green('Local playground generated at: ')) + c.dim(playgroundPath))
   console.log()
 }