declare global {
  interface Window {
    speak(s: string, lang?: string): void
  }
}

export function speak (s: string, lang?: string) {
  lang = lang || 'zh-CN'

  if (process.client) {
    let trueLang = ''

    const voices = speechSynthesis.getVoices()
    const [la1, la2] = lang.split(/-_/)
    if (la2) {
      const langRegex = new RegExp(`${la1}[-_]${la2}`, 'i')
      const matchedLang = voices.filter((v) => langRegex.test(v.lang))
      if (matchedLang.length > 0) {
        trueLang = matchedLang.sort((v1, v2) => v1.localService
          ? -1 : v2.localService ? 1 : 0)[0].lang
      }
    }
    if (!trueLang) {
      const langRegex = new RegExp(`^${la1}`, 'i')
      const matchedLang = voices.filter((v) => langRegex.test(v.lang))
      if (matchedLang.length > 0) {
        trueLang = matchedLang.sort((v1, v2) => v1.localService
          ? -1 : v2.localService ? 1 : 0)[0].lang
      }
    }

    if (trueLang) {
      const u = new SpeechSynthesisUtterance(s)
      u.lang = trueLang
      speechSynthesis.speak(u)
    }
  }
}

if (process.client) {
  window.speak = speak

  document.body.addEventListener('keydown', (evt) => {
    if (evt.code === 'KeyS') {
      const s = getSelection()
      if (s) {
        speak(s.toString())
      }
    }
  })
}