import { createI18n } from 'vue-i18n'
import zhCN from './zh-CN'
import enUS from './en-US'

const LOCALE_STORAGE_KEY = 'app_locale'
const LOCALE_CHANGE_EVENT = 'app-locale-changed'
const DEFAULT_LOCALE = 'zh-CN'

const messages = {
  'zh-CN': zhCN,
  'en-US': enUS
}

function unwrapMessageParam(value) {
  if (value && typeof value === 'object' && 'value' in value) {
    return value.value
  }
  return value
}

function normalizeMessageParams(params = {}) {
  return Object.keys(params).reduce((result, key) => {
    result[key] = unwrapMessageParam(params[key])
    return result
  }, {})
}

function replaceMessageParams(message, params = {}) {
  if (typeof message !== 'string') return message
  return Object.keys(params).reduce((result, key) => {
    const pattern = new RegExp(`\\{\\s*${key}\\s*\\}`, 'g')
    const value = params[key]
    return result.replace(pattern, value == null ? '' : String(value))
  }, message)
}

function normalizeLocale(locale) {
  if (locale === 'zh' || locale === 'zh_CN' || locale === 'zh-Hans') return 'zh-CN'
  if (locale === 'en' || locale === 'en_US') return 'en-US'
  return locale === 'en-US' ? 'en-US' : 'zh-CN'
}

function getSavedLocale() {
  try {
    const locale = uni.getStorageSync(LOCALE_STORAGE_KEY)
    if (locale) {
      return normalizeLocale(locale)
    }
  } catch (error) {
  }
  const systemLocale = typeof uni.getLocale === 'function' ? uni.getLocale() : DEFAULT_LOCALE
  return normalizeLocale(systemLocale)
}

const i18n = createI18n({
  legacy: false,
  locale: getSavedLocale(),
  fallbackLocale: DEFAULT_LOCALE,
  globalInjection: true,
  messages,
  missingWarn: false,
  fallbackWarn: false,
  missing: (locale, key) => key
})

const rawGlobalTranslate = i18n.global.t.bind(i18n.global)

i18n.global.t = (...args) => {
  const translated = rawGlobalTranslate(...args)
  const paramsArg = args.find((arg) => arg && typeof arg === 'object' && !Array.isArray(arg))
  if (!paramsArg) {
    return translated
  }
  return replaceMessageParams(translated, normalizeMessageParams(paramsArg))
}

const literalMap = {
  '首页': 'nav.home',
  '报表': 'tab.report',
  '管理': 'tab.work',
  '我的': 'tab.mine',
  '返回': 'dashboard.back',
  '查询': 'functionCommon.search',
  '取消': 'functionCommon.cancel',
  '保存': 'functionCommon.save',
  '加载中...': 'functionCommon.loading',
  '正在加载更多...': 'functionCommon.loadingMore',
  '没有更多数据了': 'functionCommon.noMoreData',
  '缺少ID，无法查看详情': 'functionCommon.noIdView',
  '缺少ID，无法编辑': 'functionCommon.noIdEdit',
  '缺少ID，无法删除': 'functionCommon.noIdDelete',
  '加载失败': 'functionCommon.loadFailed',
  '删除成功': 'functionCommon.deleteSuccess',
  '删除失败': 'functionCommon.deleteFailed',
  '保存失败': 'functionCommon.saveFailed',
  '新增成功': 'functionCommon.createSuccess',
  '更新成功': 'functionCommon.updateSuccess',
  '确认删除': 'functionCommon.confirmDelete',
  '上传中': 'functionCommon.uploading',
  '图片上传失败': 'functionCommon.uploadImageFailed',
  '是': 'functionCommon.yes',
  '否': 'functionCommon.no',
  '暂无待办任务': 'dashboard.noTodo',
  '模具出库': 'moldGet.moduleName',
  '模具出库详情': 'moldGet.detailTitle',
  '模具入库': 'moldReturn.moduleName',
  '模具入库详情': 'moldReturn.detailTitle',
  '上下模': 'moldOperate.moduleName',
  '上下模详情': 'moldOperate.detailTitle',
  '点检项库': 'moldInspectionItems.moduleName',
  '点检项库详情': 'moldInspectionItems.detailTitle',
  '点检模板': 'moldInspectionPlan.moduleName',
  '点检模板详情': 'moldInspectionPlan.detailTitle',
  '点检任务': 'moldTaskConfig.moduleName',
  '点检任务详情': 'moldTaskConfig.detailTitle',
  '设备点检任务': 'equipmentInspectionTasks.moduleName',
  '设备点检任务详情': 'equipmentInspectionTasks.detailTitle',
  '设备点检记录': 'equipmentInspectionRecord.moduleName',
  '设备点检记录详情': 'equipmentInspectionRecord.detailTitle',
  '点检记录': 'moldWorkOrder.moduleName',
  '点检记录详情': 'moldWorkOrder.detailTitle'
}

export function getCurrentLocale() {
  return i18n.global.locale.value
}

export function setLocale(locale) {
  const nextLocale = normalizeLocale(locale)
  i18n.global.locale.value = nextLocale
  uni.setStorageSync(LOCALE_STORAGE_KEY, nextLocale)
  uni.$emit(LOCALE_CHANGE_EVENT, nextLocale)
  return nextLocale
}

export function translateLiteral(text) {
  if (typeof text !== 'string') return text
  const key = literalMap[text]
  if (key) return i18n.global.t(key)
  return text
}

export function translateWithParams(key, params = {}) {
  const normalizedParams = normalizeMessageParams(params)
  const translated = i18n.global.t(key, normalizedParams)
  return replaceMessageParams(translated, normalizedParams)
}

export function initializeLocale() {
  setLocale(getSavedLocale())
}

export function setNavigationTitle(key) {
  uni.setNavigationBarTitle({
    title: i18n.global.t(key)
  })
}

export function onLocaleChange(callback) {
  uni.$on(LOCALE_CHANGE_EVENT, callback)
}

export function offLocaleChange(callback) {
  uni.$off(LOCALE_CHANGE_EVENT, callback)
}

export default i18n