%D \module
%D   [       file=strc-lev,
%D        version=2010.09.23,
%D          title=\CONTEXT\ Structure Macros,
%D       subtitle=Automatic Levels,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright=PRAGMA-ADE / Hans Hagen]
%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 Structure Macros / Automatic Levels}

%D This module is the result of a discussion between Alan Braslau and
%D me. I used to have a private (\MKII) module for this but the new
%D structure code in \MKIV\ is more suitable for this so now we have
%D it as core functionality. For the moment this an experiment that
%D Alan and I conduct so it might evolve.

\registerctxluafile{strc-lev}{1.001}

\unprotect

\unexpanded\def\definestructurelevels{\dodoubleargument\dodefinestructurelevels}
\unexpanded\def\startstructurelevel  {\dosingleempty\dostartstructurelevel}

\unexpanded\def\dodefinestructurelevels[#1][#2]{\ctxlua{structures.sections.defineautolevels("#1","#2")}}
\unexpanded\def\dostartstructurelevel      [#1]{\ctxlua{structures.sections.startautolevel("#1")}}
\unexpanded\def\stopstructurelevel             {\ctxlua{structures.sections.stopautolevel()}}

\unexpanded\def\nostartstructurehead{\dotripleargument\nonostartstructurehead}
\unexpanded\def\nostopstructurehead {\dosingleargument\nonostopstructurehead }

\unexpanded\def\dostartstructurelevel[#1]%
  {\doifassignmentelse{#1}
     {\ctxlua{structures.sections.startautolevel("\v!default")}[#1]}
     {\ctxlua{structures.sections.startautolevel("#1")}}}

\unexpanded\def\nonostartstructurehead[#1][#2][#3]%
  {\blank
   \noindentation{\tttf[start missing structure level #1]}
   \blank}

\unexpanded\def\nonostopstructurehead[#1]%
  {\blank
   \noindentation{\tttf[stop missing structure level #1]}
   \blank}

\definestructurelevels
  [\v!default]
  [\v!chapter,
   \v!section,
   \v!subsection,
   \v!subsubsection,
   \v!subsubsubsection,
   \v!subsubsubsubsection]

\protect \endinput

% \starttext

% \definehead[xxxxxxsection][subsubsection]
% \setuphead [xxxxxxsection][color=red]

% \definestructurelevels[main][chapter,section,subsection,subsubsection]
% \definestructurelevels[next][chapter,section,subsection,xxxxxxsection]

% \startstructurelevel [main] [title=first top level]

%     \startstructurelevel [main] [title=first lower level]
%         \startstructurelevel [main] [title=second lower level]
%             \startstructurelevel [main] [title=third lower level]
%                 test
%             \stopstructurelevel
%         \stopstructurelevel
%     \stopstructurelevel

%     \startstructurelevel [main] [title=first lower level]
%         \startstructurelevel [main] [title=second lower level]
%             \startstructurelevel [next] [title=third lower level]
%                 test
%             \stopstructurelevel
%         \stopstructurelevel
%     \stopstructurelevel

% \stopstructurelevel


% \stoptext