Language handler for multilingual MP

language.js

import regeneratorRuntime from '../utils/runtime'
import wxp from '../utils/wxp'
import store from '../store'

// define our default locale here
const defaultLanguage = 'en'

// get any stored language settings from localStorage
const getStoredLanguage = async () => {
  try {
    const { data } = await wxp.getStorage({ key: 'language' })
    return data
  } catch (error) {
    return null
  }
}

// get the user's phone language
const getPhoneLanguage = async () => {
  const { language } = await wxp.getSystemInfo()
  return language
}

// check if our store's current language is different than what we are passing
const storeNeedsUpdate = (language) => {
  return store.getLanguage() !== language
}

// attempt to set a new language if it is supported or fallback to the default
export const setLanguage = async (newLanguage) => {
  const allowedLanguages = ['en', 'zh']
  let language = defaultLanguage
  if (allowedLanguages.indexOf(newLanguage) !== -1) {
    language = newLanguage
  }
  if (storeNeedsUpdate(language)) {
    await store.update({ language })
  }
  await wxp.setStorage({
    key: 'language',
    data: language
  })
}

// automatically get and process the user's phone language and set
const setAutoLanguage = async () => {
  let language = defaultLanguage
  try {
    const phoneLanguage = await getPhoneLanguage()
    language = phoneLanguage.split('_').shift().split('-').shift()
  } catch (error) {
    console.error('error auto setting language', error)
  } finally {
    await setLanguage(language)
  }
}

// automatically retrieve stored language or get user's phone language and set. use this in appLaunch()
export const initLanguage = async () => {
  const storedLanguage = await getStoredLanguage()
  if (storedLanguage) {
    await store.update({ language: storedLanguage })
    return
  }
  await setAutoLanguage()
}