libs/web/luasrc/i18n.lua

   1 --[[
   2 LuCI - Internationalisation
   3
   4 Description:
   5 A very minimalistic but yet effective internationalisation module
   6
   7 FileId:
   8 $Id$
   9
  10 License:
  11 Copyright 2008 Steven Barth <steven@midlink.org>
  12
  13 Licensed under the Apache License, Version 2.0 (the "License");
  14 you may not use this file except in compliance with the License.
  15 You may obtain a copy of the License at
  16
  17         http://www.apache.org/licenses/LICENSE-2.0
  18
  19 Unless required by applicable law or agreed to in writing, software
  20 distributed under the License is distributed on an "AS IS" BASIS,
  21 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  22 See the License for the specific language governing permissions and
  23 limitations under the License.
  24
  25 ]]--
  26
  27 --- LuCI translation library.
  28 module("luci.i18n", package.seeall)
  29 require("luci.util")
  30
  31 table   = {}
  32 i18ndir = luci.util.libpath() .. "/i18n/"
  33 loaded  = {}
  34 context = luci.util.threadlocal()
  35 default = "en"
  36
  37 --- Clear the translation table.
  38 function clear()
  39         table = {}
  40 end
  41
  42 --- Load a translation and copy its data into the translation table.
  43 -- @param file  Language file
  44 -- @param lang  Two-letter language code
  45 -- @param force Force reload even if already loaded (optional)
  46 -- @return              Success status
  47 function load(file, lang, force)
  48         lang = lang and lang:gsub("_", "-") or ""
  49         if force or not loaded[lang] or not loaded[lang][file] then
  50                 local f = loadfile(i18ndir .. file .. "." .. lang .. ".lua") or
  51                         loadfile(i18ndir .. file .. "." .. lang .. ".lua.gz")
  52
  53                 if f then
  54                         table[lang] = table[lang] or {}
  55                         setfenv(f, table[lang])
  56                         f()
  57                         loaded[lang] = loaded[lang] or {}
  58                         loaded[lang][file] = true
  59                         return true
  60                 else
  61                         return false
  62                 end
  63         else
  64                 return true
  65         end
  66 end
  67
  68 --- Load a translation file using the default translation language.
  69 -- Alternatively load the translation of the fallback language.
  70 -- @param file  Language file
  71 -- @param force Force reload even if already loaded (optional)
  72 function loadc(file, force)
  73         load(file, default, force)
  74         return load(file, context.lang, force)
  75 end
  76
  77 --- Set the context default translation language.
  78 -- @param lang  Two-letter language code
  79 function setlanguage(lang)
  80         context.lang = lang:gsub("_", "-")
  81 end
  82
  83 --- Return the translated value for a specific translation key.
  84 -- @param key   Translation key
  85 -- @param def   Default translation
  86 -- @return              Translated string
  87 function translate(key, def)
  88         return (table[context.lang] and table[context.lang][key])
  89                 or (table[default] and table[default][key])
  90                 or def
  91 end
  92
  93 --- Return the translated value for a specific translation key and use it as sprintf pattern.
  94 -- @param key           Translation key
  95 -- @param default       Default translation
  96 -- @param ...           Format parameters
  97 -- @return                      Translated and formatted string
  98 function translatef(key, default, ...)
  99         return translate(key, default):format(...)
 100 end