const fs = require('fs')
const path = require('path')

function walk(dir, out = []) {
  for (const name of fs.readdirSync(dir)) {
    const p = path.join(dir, name)
    if (fs.statSync(p).isDirectory()) walk(p, out)
    else if (/\.vue$/.test(name)) out.push(p)
  }
  return out
}

function isValidUtf8Chinese(buf) {
  return buf.includes(Buffer.from([0xe5, 0x9c, 0xba, 0xe6, 0x99, 0xaf])) // 锟斤拷锟斤拷
    || buf.includes(Buffer.from([0xe8, 0xb0, 0x83, 0xe8, 0xaf, 0x95])) // 锟斤拷锟斤拷
}

function shouldConvert(buf) {
  if (buf[0] === 0xef && buf[1] === 0xbb && buf[2] === 0xbf) {
    return !isValidUtf8Chinese(buf) && buf.toString('utf8').includes('\uFFFD')
  }
  if (isValidUtf8Chinese(buf)) return false
  const asUtf = buf.toString('utf8')
  if (asUtf.includes('\uFFFD')) return true
  // GBK double-byte for CJK
  return /[\u0080-\u00ff]/.test(buf.slice(300, 400).toString('latin1'))
}

function convertFile(file) {
  const buf = fs.readFileSync(file)
  if (!shouldConvert(buf)) return false
  const text = new TextDecoder('gbk').decode(buf).replace(/^\uFEFF/, '')
  if (!/[\u4e00-\u9fff]/.test(text)) return false
  fs.writeFileSync(file, text, 'utf8')
  return true
}

const roots = [
  path.join(__dirname, '../src/views/lobster'),
  path.join(__dirname, '../../saas-companyui/src/views/lobster')
]

let count = 0
for (const root of roots) {
  if (!fs.existsSync(root)) continue
  for (const file of walk(root)) {
    if (convertFile(file)) {
      count++
      console.log('converted', path.relative(path.join(__dirname, '..', '..'), file))
    }
  }
}
console.log('done', count, 'files')