%D \module
%D   [       file=mult-aux,
%D        version=2010.08.2,
%D          title=\CONTEXT\ Multilingual Macros,
%D       subtitle=helpers,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

%D This is a subset of the \MKIV\ variant which has more comments). There
%D is no support for attributes (fonts and color). This code is mostly
%D meant for usage in modules that are backported from \MKIV.

\writestatus{loading}{ConTeXt Multilingual Macros / Helpers}

\unprotect

%D \starttyping
%D \unprotect
%D     \def\????aa{@@@@aa}
%D
%D     \installparameterhandler  \????aa {whatever}
%D     \installsetuphandler      \????aa {whatever}
%D     \installdefinehandler     \????aa {whatever} \????aa % #3 == defaultroot
%D
%D   % \installcommandhandler    \????aa {whatever} \????aa
%D \protect
%D
%D % \whateverparameter \c!test
%D % \whateverparameterhash \c!test
%D % \namedwhateverparameter \mycurrentwhatever \c!test
%D % \everydefinewhatever (sets \currentwhatever)
%D % \everypresetwhatever (can be used to reset parameters as we can redefine)
%D % \everysetupwhatever (sets \currentwhatever)
%D
%D \starttext
%D     \definewhatever[first] \definewhatever[second][first]
%D                                           test: \def\currentwhatever{first}  \whateverparameter{method} \par
%D     \setupwhatever        [method=unset]  test: \def\currentwhatever{first}  \whateverparameter{method} \par
%D     \setupwhatever[first] [method=first]  test: \def\currentwhatever{first}  \whateverparameter{method} \par
%D                                           test: \def\currentwhatever{second} \whateverparameter{method} \par
%D     \setupwhatever[second][method=second] test: \def\currentwhatever{second} \whateverparameter{method} \par
%D \stoptext
%D \stoptyping

\unexpanded\def\doinstallparameterhandler#1#2#3#4#5#6#7#8#9%
  {\def#3##1{\csname#4{#1#2}{##1}\endcsname}%
   \def#4##1##2{\ifcsname##1##2\endcsname##1##2\else\expandafter#5\csname##1\s!parent\endcsname{##2}\fi}%
   \def#5##1##2{\ifx##1\relax\s!empty\else#4{##1}{##2}\fi}%
   \def#6##1##2{\csname#4{#1##1}{##2}\endcsname}%
   \def#7##1{\detokenize\expandafter\expandafter\expandafter{\csname#1##1\endcsname}}% always root
   \def#8{\dosetvalue{#1}}% ##1 {##2} (braces are mandate)
   \def#9{\doletvalue{#1}}}% ##1 ##2

\unexpanded\def\installparameterhandler#1#2%
  {%\message{\detokenize{#1}/\detokenize{#2}}%
   \normalexpanded
     {\doinstallparameterhandler
        {\noexpand#1}% \??aa
        \expandafter\noexpand\csname current#2\endcsname
        \expandafter\noexpand\csname #2parameter\endcsname
        \expandafter\noexpand\csname do#2parameter\endcsname
        \expandafter\noexpand\csname do#2parentparameter\endcsname
        \expandafter\noexpand\csname named#2parameter\endcsname
        \expandafter\noexpand\csname detokenized#2parameter\endcsname
        \expandafter\noexpand\csname doset#2parameter\endcsname
        \expandafter\noexpand\csname dolet#2parameter\endcsname}}

\unexpanded\def\doinstallparameterhashhandler#1#2#3#4#5%
  {\def#3##1{#4{#1#2}{##1}}%
   \def#4##1##2{\ifcsname##1##2\endcsname##1\else\expandafter#5\csname##1\s!parent\endcsname{##2}\fi}%
   \def#5##1##2{\ifx##1\relax\else#4{##1}{##2}\fi}}

\unexpanded\def\installparameterhashhandler#1#2%
  {\normalexpanded
     {\doinstallparameterhashhandler
        {\noexpand#1}% \??aa
        \expandafter\noexpand\csname current#2\endcsname
        \expandafter\noexpand\csname #2parameterhash\endcsname
        \expandafter\noexpand\csname do#2parameterhash\endcsname
        \expandafter\noexpand\csname do#2parentparameterhash\endcsname}}


\unexpanded\def\doinstalldefinehandler#1#2#3#4#5#6#7%
  {\unexpanded\def#2{\dotripleempty#5}%
   \newtoks#6%
   \newtoks#7%
   \def#5[##1][##2][##3]% [child][parent][settings]
     {\edef#4{##1}%     % [child]        [settings]
      \the#6% predefine % [child][parent]
      \ifthirdargument  % [child]
        \getparameters[#1#4][\s!parent=#1##2,##3]%
      \else\ifsecondargument
        \doifassignmentelse{##2}
          {\getparameters[#1#4][\s!parent=#3,##2]}
          {\getparameters[#1#4][\s!parent=#1##2]}%
      \else
        \getparameters[#1#4][\s!parent=#3]%
      \fi\fi
      \the#7}}

\unexpanded\def\installdefinehandler#1#2#3%
  {\normalexpanded
     {\doinstalldefinehandler
        {\noexpand#1}% \??aa
        \expandafter\noexpand\csname define#2\endcsname
        {\noexpand#3}% root
        \expandafter\noexpand\csname current#2\endcsname
        \expandafter\noexpand\csname d@define#2\endcsname
        \expandafter\noexpand\csname everypreset#2\endcsname
        \expandafter\noexpand\csname everydefine#2\endcsname}}

\unexpanded\def\doinstallsetuphandler#1#2#3#4#5%
  {\unexpanded\def#2{\dodoubleempty#4}%
   \newtoks#5%
   \def#4[##1][##2]% maybe helper
     {\ifsecondargument
        \def\docommand####1% we will have a simple one as well
          {\edef#3{####1}%
           \getparameters[#1#3][##2]%
           \the#5}%
        \processcommalist[##1]\docommand
      \else
        \let#3\empty
        \getparameters[#1][##1]%
        \the#5%
      \fi}}

\unexpanded\def\installsetuphandler#1#2%
  {\normalexpanded
     {\doinstallsetuphandler
        {\noexpand#1}% \??aa
        \expandafter\noexpand\csname setup#2\endcsname
        \expandafter\noexpand\csname current#2\endcsname
        \expandafter\noexpand\csname d@setup#2\endcsname
        \expandafter\noexpand\csname everysetup#2\endcsname}}

\unexpanded\def\installcommandhandler#1#2#3% \??self name \??parent (can be \??self)
  {\installparameterhandler    {#1}{#2}%
   \installparameterhashhandler{#1}{#2}%
   \installdefinehandler       {#1}{#2}{#3}%
   \installsetuphandler        {#1}{#2}}

\unexpanded\def\installnamespace#1%
  {\setvalue{????#1}{@@@@#1}}

\protect