i18n.js

export default function () {
  const i18n = {
    en: {
      won: 'won',
      total: 'total',
      averageLength: 'average length',
      tooHard: 'too difficult?<br>type <code>skip</code>',
      rule0: 'Find a <b>valid</b> JavaScript expression',
      rule1: 'whose value is <b>(Number)24</b>.',
      rule2: 'Each of the four given numerical digits <b>must appear once</b>, and <b>no other</b> digits are allowed.',
      rule3: 'Besides digits, <b>only</b> these operators are allowed: <code>+</code> <code>-</code> <code>*</code> <code>/</code> <code>%</code> <code>~</code> <code>&amp;</code> <code>|</code> <code>^</code> <code>&lt;&lt;</code> <code>&gt;&gt;</code> <code>(</code> <code>)</code> and <code>x</code> <code>o</code>(after a given <code>0</code>).<br><small>* Can you do it like a boss? Try not to use parentheses <code>(</code> <code>)</code>.</small>',
      boss: '',
      rule4: 'In additional, to avoid <code>-~</code> from appearing continuously, <code>-</code> is <b>not allowed</b> to be used as a unary operator.',
    },
    zh: {
      won: '已获胜',
      total: '总局数',
      averageLength: '平均长度',
      tooHard: '太难了？<br>输入 <code>skip</code>',
      rule0: '求一个<b>合法的</b> JavaScript 表达式，',
      rule1: '其值为<b>整数 24</b>。',
      rule2: '四个给定的数字<b>恰好</b>在表达式中出现一次，未给定数字<b>不允许</b>出现。',
      rule3: '除数字外，表达式中<b>仅允许</b>包含下列运算符：<code>+</code> <code>-</code> <code>*</code> <code>/</code> <code>%</code> <code>~</code> <code>&amp;</code> <code>|</code> <code>^</code> <code>&lt;&lt;</code> <code>&gt;&gt;</code> <code>(</code> <code>)</code> 以及 <code>x</code> <code>o</code>（在给定的 <code>0</code> 后面）。<br><small>* 挑战自己！试着不使用小括号 <code>(</code> <code>)</code>。</small>',
      rule4: '另外，为了防止 <code>-~</code> 连续出现，<b>不允许</b>将 <code>-</code> 用作一元运算符。',
    },
  }

  let language = 'en'
  for (let i = 0; i < navigator.languages.length; i += 1) {
    const lang = navigator.languages[i].toLowerCase()
    if (lang in i18n) {
      language = lang
      break
    }
  }
  document.body.innerHTML =
    document.body.innerHTML.replace(/\{\{.*?\}\}/g, match => i18n[language][match.slice(2, -2)])
}