% ----------------------------------------------------------------------------
% the XSIM package - translations module
% 
%   eXercise Sheets IMproved
% 
% ----------------------------------------------------------------------------
% Clemens Niederberger
% Web:    https://github.com/cgnieder/xsim
% E-Mail: contact@mychemistry.eu
% ----------------------------------------------------------------------------
% Copyright 2017 Clemens Niederberger
% 
% This work may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3
% of this license or (at your option) any later version.
% The latest version of this license is in
%   http://www.latex-project.org/lppl.txt
% and version 1.3 or later is part of all distributions of LaTeX
% version 2005/12/01 or later.
% 
% This work has the LPPL maintenance status `maintained'.
% 
% The Current Maintainer of this work is Clemens Niederberger.
% ----------------------------------------------------------------------------
% If you have any ideas, questions, suggestions or bugs to report, please
% feel free to contact me.
% ----------------------------------------------------------------------------
\XSIMmodule{translations}{language settings for XSIM}

\RequirePackage{translations}

\msg_new:nnn {xsim} {language-not-defined}
  {
    You~ chose~ the~ language~ `#1'~ which~ is~ not~ defined~ by~ xsim.~
    `english'~ is~ used~ instead.~ If~ you~ just~ mistyped~ try~ again!~
    Otherwise~ contact~ the~ author~ and~ he'll~ probably~ add~ your~ language.
  }

% --------------------------------------------------------------------------

\bool_new:N      \l__xsim_language_auto_bool
\bool_set_true:N \l__xsim_language_auto_bool
% this token list will hold the chosen language for xsim; since the
% language is either chosen automatically or by option it is only available at
% begin document
\tl_new:N  \l_xsim_language_tl
\tl_set:Nn \l_xsim_language_tl {english}
\tl_new:N  \l__xsim_current_language_tl

\tl_const:Nn \c__xsim_keyword_prefix_tl {xsim-keyword-}

% ----------------------------------------------------------------------------
  
\prop_new:N \g_xsim_translations_prop

% translate the key #1
\cs_new:Npn \xsim_translate:n #1
  {
    \bool_if:NTF \l__xsim_language_auto_bool
      { \GetTranslation { \c__xsim_keyword_prefix_tl #1 } }
      {
        \GetTranslationFor
          { \l_xsim_language_tl }
          { \c__xsim_keyword_prefix_tl #1 }
      }
  }

\AtBeginDocument{
  \bool_if:NTF \l__xsim_language_auto_bool
    {
      \tl_set:Nx \l_xsim_language_tl
        { \@trnslt@language{\@trnslt@current@language} }
    }
    {
      \tl_set_eq:NN
        \l_xsim_language_tl
        \l__xsim_current_language_tl
    }   
}

% ----------------------------------------------------------------------------
% #1: keyword
% #2: language
% #3: translation
\cs_new_protected:Npn \__xsim_declare_translation:nw #1#2=#3\q_stop
  {
    \tl_set:Nx \l__xsim_tmpa_tl { \tl_trim_spaces:n {#2} }
    \tl_set:Nx \l__xsim_tmpb_tl { \tl_trim_spaces:n {#3} }
    \xsim_declare_translation:VnV
      \l__xsim_tmpa_tl
      {#1}
      \l__xsim_tmpb_tl
  }

% #1: language
% #2: keyword
% #3: translation
\cs_new_protected:Npn \xsim_declare_translation:nnn #1#2#3
  {
    \xsim_verbose:n
      { Declaring~ `#1'~ tranlation~ of~ `#2':~ `#3'. }
    \declaretranslation
      {#1}
      { \c__xsim_keyword_prefix_tl #2 }
      {#3}
    \prop_gput:Nnn \g_xsim_translations_prop {#2(#1)} {#3}
  }
\cs_generate_variant:Nn \xsim_declare_translation:nnn {V,VnV}

% #1: key
% #2: csv list: { <lang1> = <translation1> , <lang2> = <translation2> }
\cs_new_protected:Npn \xsim_declare_translations:nn #1#2
  {
    \clist_map_inline:nn {#2}
      { \__xsim_declare_translation:nw {#1} ##1 \q_stop }
  }

\cs_new:Npn \__xsim_parse_translate_list_entry:nnn #1#2#3 {}

\cs_new_protected:Npn \__xsim_parse_translate_list_entry:www #1(#2)\q_mark#3\q_stop
  { \__xsim_parse_translate_list_entry:nnn {#1} {#2} {#3} }

\cs_new_protected:Npn \xsim_for_all_translations_do:n #1
  {
    \cs_set:Npn \__xsim_parse_translate_list_entry:nnn ##1##2##3 {#1}
    \prop_map_inline:Nn \g_xsim_translations_prop
      { \__xsim_parse_translate_list_entry:www ##1 \q_mark ##2 \q_stop }
  }

% ----------------------------------------------------------------------------

\keys_define:nn {xsim}
  {
    language .value_required:n = true ,
    language .code:n =
      \tl_if_eq:nnTF {#1} {auto}
        { \bool_set_true:N \l__xsim_language_auto_bool }
        {
          \bool_set_false:N \l__xsim_language_auto_bool
          \tl_set:Nn \l__xsim_current_language_tl {#1}
        } ,
    language .initial:n = auto
  }

% ----------------------------------------------------------------------------
\file_input_stop: