
% \section{Programmer's interface}
%
% \iffalse
%    \begin{macrocode}
%<*fontspec&(xetexx|luatex)>
%    \end{macrocode}
% \fi
%
%
%
% These functions are not used directly by fontspec when defining fonts;
% they are designed to be used by other packages who wish to do font-related
% things on top of fontspec itself.
%
% Because I haven't fully explored how these functions will behave in
% practise, I am not giving them user-level names. As it becomes more clear
% which of these should be accessible by document writers, I'll open them up
% a little more.
%
% All functions are defined assuming that the font to be queried is
% currently selected as a fontspec font. (I.e., via \verb|\fontspec| or
% from a \verb|\newfontfamily| macro or from \verb|\setmainfont| and so on.)
%
% \begin{macro}{\fontspec_if_fontspec_font:TF}
% Test whether the currently selected font has been loaded by fontspec.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_fontspec_font: {TF,T,F}
 {
  \cs_if_exist:cTF {g_@@_ \f@family _prop} \prg_return_true: \prg_return_false:
 }
%    \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontspec_if_aat_feature:nnTF}
% Conditional to test if the currently selected font contains the \AAT\
% feature (|#1|,|#2|).
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_aat_feature:nn {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \bool_if:NTF \l_@@_atsui_bool
     {
      \@@_make_AAT_feature_string:nnTF {#1}{#2}
        \prg_return_true: \prg_return_false:
     }
     {
      \prg_return_false:
     }
   }
   {
    \prg_return_false:
   }
 }
%    \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontspec_if_opentype:TF}
% Test whether the currently selected font is an OpenType font.
% Always true for LuaTeX fonts.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_opentype: {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool \prg_return_true: \prg_return_false:
   }
   {
    \prg_return_false:
   }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_feature:nTF}
% Test whether the currently selected font contains the raw OpenType
% feature |#1|. E.g.: |\fontspec_if_feature:nTF {pnum} {True} {False}|
% Returns false if the font is not loaded by fontspec or is not an OpenType
% font.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_feature:n {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \prop_get:cnN {g_@@_ \f@family _prop} {script-num} \l_@@_tmp_tl
      \int_set:Nn \l_@@_script_int {\l_@@_tmp_tl}

      \prop_get:cnN {g_@@_ \f@family _prop} {lang-num} \l_@@_tmp_tl
      \int_set:Nn \l_@@_language_int {\l_@@_tmp_tl}

      \prop_get:cnN {g_@@_ \f@family _prop} {script-tag}  \l_fontspec_script_tl
      \prop_get:cnN {g_@@_ \f@family _prop} {lang-tag}  \l_fontspec_lang_tl

      \@@_check_ot_feat:nTF {#1} {\prg_return_true:} {\prg_return_false:}
     }
     {
      \prg_return_false:
     }
   }
   {
    \prg_return_false:
   }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_feature:nnnTF}
% Test whether the currently selected font with raw OpenType script tag |#1| and
% raw OpenType language tag |#2| contains the raw OpenType feature tag |#3|.
% E.g.:\\ |    \fontspec_if_feature:nTF {latn} {ROM} {pnum} {True} {False}|
% Returns false if the font is not loaded by fontspec or is not an OpenType
% font.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_feature:nnn {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \@@_iv_str_to_num:Nn \l_@@_script_int {#1}
      \@@_iv_str_to_num:Nn \l_@@_language_int {#2}
      \@@_check_ot_feat:nTF {#3} \prg_return_true: \prg_return_false:
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_script:nTF}
% Test whether the currently selected font contains the raw OpenType
% script |#1|. E.g.: |\fontspec_if_script:nTF {latn} {True} {False}|
% Returns false if the font is not loaded by fontspec or is not an OpenType
% font.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_script:n {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \@@_check_script:nTF {#1} \prg_return_true: \prg_return_false:
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_language:nTF}
% Test whether the currently selected font contains the raw OpenType language
% tag |#1|. E.g.: |\fontspec_if_language:nTF {ROM} {True} {False}|.
% Returns false if the font is not loaded by fontspec or is not an OpenType
% font.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_language:n {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \prop_get:cnN {g_@@_ \f@family _prop} {script-num} \l_@@_tmp_tl
      \int_set:Nn \l_@@_script_int {\l_@@_tmp_tl}
      \prop_get:cnN {g_@@_ \f@family _prop} {script-tag}  \l_fontspec_script_tl

      \@@_check_lang:nTF {#1} \prg_return_true: \prg_return_false:
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_language:nnTF}
% Test whether the currently selected font contains the raw OpenType language
% tag |#2| in script |#1|. E.g.: |\fontspec_if_language:nnTF {cyrl} {SRB} {True} {False}|.
% Returns false if the font is not loaded by fontspec or is not an OpenType
% font.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_language:nn {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \tl_set:Nn \l_fontspec_script_tl {#1}
      \@@_iv_str_to_num:Nn \l_@@_script_int {#1}
      \@@_check_lang:nTF {#2} \prg_return_true: \prg_return_false:
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontspec_if_current_script:nTF}
% Test whether the currently loaded font is using the specified raw
% OpenType script tag |#1|.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_current_script:n {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \prop_get:cnN {g_@@_ \f@family _prop} {script-tag}  \l_@@_tmp_tl
      \str_if_eq:nVTF {#1}  \l_@@_tmp_tl
        {\prg_return_true:} {\prg_return_false:}
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_current_language:nTF}
% Test whether the currently loaded font is using the specified raw
% OpenType language tag |#1|.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_current_language:n {TF,T,F}
 {
  \fontspec_if_fontspec_font:TF
   {
    \prop_get:cnN {g_@@_ \f@family _prop} {fontdef} \l_@@_fontdef_tl
    \@@_primitive_font_set:Nnn \l_fontspec_font {\l_@@_fontdef_tl} {\f@size pt}
    \@@_set_font_type:
    \bool_if:NTF \l_@@_ot_bool
     {
      \prop_get:cnN {g_@@_ \f@family _prop} {lang-tag}  \l_@@_tmp_tl
      \str_if_eq:nVTF {#1} \l_@@_tmp_tl
        {\prg_return_true:} {\prg_return_false:}
     }
     { \prg_return_false: }
   }
   { \prg_return_false: }
 }
%    \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontspec_set_family:Nnn}
% \darg{family}
% \darg{fontspec features}
% \darg{font name}
% Defines a new font family from given \meta{features} and \meta{font},
% and stores the name in the variable \meta{family}.
% See the standard \pkg{fontspec} user commands for applications of this
% function.
%
% We want to store the actual name of the font family within the \meta{family}
% variable because the actual \LaTeX\ family name is automatically generated
% by fontspec and it's easier to keep it that way.
%
% Please use |\fontspec_set_family:Nnn| instead of |\@@_select_font_family:nn|,
% which may change in the future.
%    \begin{macrocode}
\cs_new:Nn \fontspec_set_family:Nnn
 {
  \tl_set:Nn \l_@@_family_label_tl { #1 }
  \@@_select_font_family:nn {#2}{#3}
  \tl_set_eq:NN #1 \l_fontspec_family_tl
 }
\cs_generate_variant:Nn \fontspec_set_family:Nnn {c}
%    \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontspec_set_fontface:NNnn}
%    \begin{macrocode}
\cs_new:Nn \fontspec_set_fontface:NNnn
 {
  \tl_set:Nn \l_@@_family_label_tl { #1 }
  \@@_select_font_family:nn {#3}{#4}
  \tl_set_eq:NN #1 \l_fontspec_font
  \tl_set_eq:NN #2 \l_fontspec_family_tl
 }
%    \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\fontspec_font_if_exist:n}
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_font_if_exist:n {TF,T,F}
  {
    \group_begin:
      \@@_init:
      \@@_if_detect_external:nT {#1} { \@@_font_is_file: }
      \@@_primitive_font_if_exist:nTF { \@@_construct_font_call:nn {#1} {} }
        { \group_end: \prg_return_true: }
        { \group_end: \prg_return_false:  }
  }
\cs_set_eq:NN \IfFontExistsTF \fontspec_font_if_exist:nTF
%    \end{macrocode}
% \end{macro}

% \begin{macro}{\fontspec_if_current_feature:nTF}
% Test whether the currently loaded font is using the specified raw
% OpenType feature tag |#1|.
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_current_feature:n {TF,T,F}
  {
    \exp_args:Nxx \tl_if_in:nnTF
      { \fontname\font } { \tl_to_str:n {#1} }
      { \prg_return_true: } { \prg_return_false: }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontspec_if_small_caps:TF}
%    \begin{macrocode}
\prg_new_conditional:Nnn \fontspec_if_small_caps: {TF,T,F}
  {
    \@@_if_merge_shape:nTF {sc}
      {
        \tl_set_eq:Nc \l_@@_smcp_shape_tl { \@@_shape_merge:nn {\f@shape} {sc} }
      }
      {
        \tl_set:Nn \l_@@_smcp_shape_tl {sc}
      }

    \cs_if_exist:cTF { \f@encoding/\f@family/\f@series/\l_@@_smcp_shape_tl }
      {
        \tl_if_eq:ccTF
          { \f@encoding/\f@family/\f@series/\l_@@_smcp_shape_tl }
          { \f@encoding/\f@family/\f@series/\updefault }
          { \prg_return_false: }
          { \prg_return_true:  }
      }
      { \prg_return_false: }
  }
%    \end{macrocode}
% \end{macro}
%
% \iffalse
%    \begin{macrocode}
%</fontspec&(xetexx|luatex)>
%    \end{macrocode}
% \fi
