%D \module
%D   [       file=buff-par,
%D        version=2010.12.05,
%D          title=\CONTEXT\ Buffer Macros,
%D       subtitle=Parallel,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

\writestatus{loading}{ConTeXt Buffer Macros / Parallel}

\registerctxluafile{buff-par}{1.001}

%D This module is developped for Thomas Schmitz as part of
%D a project.

\unprotect

\letvalue{\??px:}\empty

\def\parallelparameter#1%
  {\csname\??px:%
     \ifcsname\??px:\currentparallel:\currentparallelinstance:#1\endcsname
       \currentparallel:\currentparallelinstance:#1%
     \else\ifcsname\??px:\currentparallel:#1\endcsname
       \currentparallel:#1%
     \else\ifcsname\??px:#1\endcsname
       #1%
     \fi\fi\fi
   \endcsname}

\unexpanded\def\defineparallel
  {\dodoubleargument\dodefineparallel}

\def\dodefineparallel[#1][#2]%
  {\ctxcommand{defineparallel("#1","#2")}%
   \processcommalist[#2]\dododefineparallel
   \setuvalue{\e!start#1}{\dostartparallelset{#1}}%
   \setuvalue{\e!stop #1}{\dostopparallelset}}

\def\dododefineparallel#1%
  {\definebuffer[#1]%%
   \setuvalue{\e!stop#1}{\dowithparallel{#1}}}

\def\dostartparallelset#1%
  {\def\currentparallel{#1}%
   \ctxcommand{nextparallel("\currentparallel")}}

\def\dostopparallelset#1%
  {}

\def\dowithparallel#1% defined moet ook aan de lua kant kunnen
  {\ctxcommand{saveparallel("\currentparallel","#1",buffers.raw("\thedefinedbuffer{#1}"))}}

\unexpanded\def\placeparallel
  {\dotripleempty\doplaceparallel}

\def\doplaceparallel[#1][#2][#3]%
  {\begingroup
   \def\currentparallel{#1}%
   \ctxcommand{placeparallel("\currentparallel","#2","#3")}%
   \endgroup}

% was: \parallelparameter\c!command}

\def\doflushparallel#1#2#3#4#5% {instance}{status}{line}{label}{content}
  {\begingroup
   \def\currentparallelinstance{#1}%
   \def\currentparallelnumber  {#2}%
   \def\currentparallelline    {#3}%
   \def\currentparallellabel   {#4}%
   \def\currentparallelcontent {#5}%
   \ifcase#2\relax
     \expandafter\noflushparalleldefault
   \or
     \expandafter\doflushparalleldefault
   \fi
   \endgroup}

\def\noflushparalleldefault{}
\def\doflushparalleldefault{\directsetup{\parallelparameter\c!setups}}

\startsetups parallel:place:default
    \hangafter1
    \hangindent4em
    \dontleavehmode
    \hbox to 3em \bgroup
        \hss
        \bf
        \doifsomething \currentparallellabel {
            \textreference[\currentparallellabel]{\currentparallelline}
        }
    \currentparallelline
    \quad
    \egroup
    \currentparallelcontent
    \par
\stopsetups

\unexpanded\def\setupparallel
  {\dotripleempty\dosetupparallel}

\def\dosetupparallel[#1][#2][#3]%
  {\ifthirdargument
     \getparameters[\??px:#1:#2:][#3]%
   \else\ifsecondargument
     \getparameters[\??px:#1:][#2]%
   \else
     \getparameters[\??px:][#1]% maybe no : here
   \fi\fi}

\setupparallel
% [\c!command=\doflushparalleldefault]
  [\c!setups=parallel:place:default]

\def\doifelseparallel#1#2%
  {\cldcontext{commands.doifelseparallel("#1","#2")}}

\def\resetparallel
  {\dodoubleempty\doresetparallel}

\def\resetparallel[#1][#2]%
  {\ctxcommand{resetparallel("#1","#2"))}}

% default

% \def\doflushparalleldefault#1#2#3#4% todo: setups instead
%   {\ifcase#1\or
%      \begingroup
%      \hangafter1
%      \hangindent4em
%      \dontleavehmode
%      \hbox to 3em{\hss\bf\doifsomething{#3}{\textreference[#3]{#2}}#2\quad}#4\par
%      \endgroup
%    \fi}

\protect \endinput

% \def\dododefineparallel#1%
%   {\setuvalue{\e!stop #1}{}%
%    \setuvalue{\e!start#1}{\dostartparallel{#1}}}
%
% \def\dostartparallel#1%
%   {\grabuntil{\e!stop#1}{\dododostartparallel{#1}}}
%
% \def\dododostartparallel#1#2%
%   {\ctxcommand{saveparallel("\currentparallel","#1",\!!bs\detokenize{#2}\!!es)}}