local state = runtime.import("state")

---@class ShowcaseI18n
local i18n = {}

local fallback_locale = "zh-Hans"

local messages = {
  ["zh-Hans"] = {
    app_title = "Lua Runtime Showcase",
    app_subtitle = "仿 Cocos Showcase：左侧管理所有示例，右侧查看说明并直接运行。",
    examples_title = "Examples",
    preview_title = "Preview / Runtime Stage",
    tab_code = "代码",
    tab_params = "参数",
    copy_code = "复制代码",
    copy_params = "复制参数",
    selected_prefix = "已选择示例：",
    status_ready = "点击按钮查看 RuntimeEvent -> Lua -> Diff / Command 示例",
    i18n_current = "当前语言",
    i18n_zh = "中文文案：运行时只传 locale，翻译由 Lua 包管理。",
    i18n_en = "English copy: Lua owns text resources and fallback policy.",
    i18n_switched = "已切换语言：",
    responsive_title = "分辨率适配",
    responsive_design = "设计分辨率",
    responsive_screen = "屏幕",
    responsive_viewport = "视口",
    responsive_phone = "模拟手机宽度",
    responsive_tablet = "模拟平板宽度",
    responsive_desktop = "模拟桌面宽度"
  },
  en = {
    app_title = "Lua Runtime Showcase",
    app_subtitle = "Cocos-style showcase: select examples on the left, inspect and run them on the right.",
    examples_title = "Examples",
    preview_title = "Preview / Runtime Stage",
    tab_code = "Code",
    tab_params = "Params",
    copy_code = "Copy code",
    copy_params = "Copy params",
    selected_prefix = "Selected example: ",
    status_ready = "Tap actions to inspect RuntimeEvent -> Lua -> Diff / Command.",
    i18n_current = "Current locale",
    i18n_zh = "中文文案：运行时只传 locale，翻译由 Lua 包管理。",
    i18n_en = "English copy: Lua owns text resources and fallback policy.",
    i18n_switched = "Locale switched: ",
    responsive_title = "Responsive Layout",
    responsive_design = "Design",
    responsive_screen = "Screen",
    responsive_viewport = "Viewport",
    responsive_phone = "Simulate phone width",
    responsive_tablet = "Simulate tablet width",
    responsive_desktop = "Simulate desktop width"
  }
}

---@param locale? string
---@return string
local function normalize(locale)
  if locale == nil or locale == "" then
    return fallback_locale
  end
  if messages[locale] ~= nil then
    return locale
  end

  local language = string.match(locale, "^([A-Za-z]+)")
  if language ~= nil and messages[language] ~= nil then
    return language
  end
  return fallback_locale
end

---@param ctx? RuntimeContext
function i18n.apply_context(ctx)
  local locale = fallback_locale
  if ctx ~= nil and ctx.locale ~= nil and ctx.locale.resolved ~= nil then
    locale = ctx.locale.resolved
  end
  state.locale = normalize(locale)
end

---@param locale string
function i18n.set_locale(locale)
  state.locale = normalize(locale)
end

---@return string
function i18n.toggle_locale()
  if state.locale == "en" then
    state.locale = "zh-Hans"
  else
    state.locale = "en"
  end
  return state.locale
end

---@return string
function i18n.current_locale()
  return normalize(state.locale)
end

---@param key string
---@return string
function i18n.t(key)
  local locale = normalize(state.locale)
  local bundle = messages[locale] or messages[fallback_locale]
  return bundle[key] or messages[fallback_locale][key] or key
end

---@param example ShowcaseExample
---@param field string
---@return string
function i18n.example_field(example, field)
  if i18n.current_locale() == "en" then
    local en_value = example[field .. "_en"]
    if en_value ~= nil and en_value ~= "" then
      return en_value
    end
  end
  return example[field]
end

---@param example ShowcaseExample
---@return string
function i18n.example_label(example)
  return i18n.example_field(example, "menu")
end

---@param example ShowcaseExample
---@return string
function i18n.example_params(example)
  return i18n.example_field(example, "params")
end

---@param example ShowcaseExample
---@return string
function i18n.example_group(example)
  return i18n.example_field(example, "group")
end

---@param action ShowcaseAction
---@return string
function i18n.action_text(action)
  if i18n.current_locale() == "en" and action.text_en ~= nil and action.text_en ~= "" then
    return action.text_en
  end
  return action.text
end

return i18n