%D \module
%D   [       file=strc-num,
%D        version=2008.10.20,
%D          title=\CONTEXT\ Structure Macros,
%D       subtitle=Basic Numbering,
%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.

\writestatus{loading}{ConTeXt Structure Macros / Basic Numbering}

\registerctxluafile{strc-num}{}

\unprotect

\startcontextdefinitioncode

% work in progress
% to be checked: can we use the command handler code here?
% all settings will move to lua

\installcorenamespace{counter}

\installcommandhandler \??counter {counter} \??counter

\aliased\let\setupcounters         \setupcounter
\aliased\let\setupstructurecounting\setupcounter % will disappear

\setupcounter
  [\c!way=\v!by\v!chapter,
%  \c!blockway=,
%  \c!prefixstarter=,
%  \c!prefixstopper=,
   \c!prefixconnector=.,
   \c!prefixsegments=\autostructureprefixsegments\rootcounterparameter,
   \c!start=\zerocount,
   \c!prefix=\v!yes,
   \c!state=\v!start]

\permanent\def\autostructureprefixsegments#1% todo: \c!prefixsegments=\v!auto
  {2:\thenamedheadlevel{\clf_way{#1\c!way}}}

\appendtoks
    \resetcounterparameter\s!counter
\to \everypresetcounter

\appendtoks
    \ifempty\currentcounterparent
        \edef\p_start{\counterparameter\c!start}%
        \clf_definecounter
           name    {\currentcounter}%
           start   \ifempty\p_start\zerocount\else\numexpr\p_start\relax\fi
           counter {\counterparameter\s!counter}%
           method  {\counterparameter\c!method}%
        \relax
        \letcounterparameter\s!name\currentcounter
    \else
      % \letcounterparameter\s!name\currentcounterparent % we need a chained clone
        \setexpandedcounterparameter\s!name{\namedcounterparameter\currentcounterparent\s!name}%
    \fi
    \strc_counters_check_setup
\to \everydefinecounter

\appendtoks
    \ifempty\currentcounter \else
        \edef\p_number{\counterparameter\c!number}%
        \ifempty\p_number \else
          \clf_setcounter{\counterparameter\s!name}\numexpr\p_number\relax
          \resetcounterparameter\c!number
        \fi
        \edef\p_start{\counterparameter\c!start}%
        \setexpandedcounterparameter\c!start{\ifempty\p_start0\else\number\p_start\fi}%
        \strc_counters_check_setup
    \fi
\to \everysetupcounter

% % % %

\permanent\def\strc_counters_way   #1{\clf_way{\namedcounterparameter{#1}\c!way}}
\permanent\def\thenamedcounterlevel#1{\xthenamedheadlevel{\clf_way{\namedcounterparameter{#1}\c!way}}}

\mutable\let\currentcounterlevel\!!zerocount % yes or no public ?

\protected\def\strc_counters_check_setup
  {\edef\p_name{\directcounterparameter\s!name}%
   \ifx\currentcounter\p_name
     \edef\currentcounterlevel{\thenamedcounterlevel\currentcounter}%
     \edef\p_start{\counterparameter\c!start}%
     \clf_checkcountersetup
       {\currentcounter}%
       \numexpr\currentcounterlevel\relax
       \numexpr\ifempty\p_start\zerocount\else\p_start\fi\relax % bug in scanner
       {\counterparameter\c!state}%
   \fi}

\permanent\protected\def\doifelsecounter #1{\clf_doifelsecounter{\namedcounterparameter{#1}\s!name}}
\permanent\protected\def\doifcounter     #1{\clf_doifcounter    {\namedcounterparameter{#1}\s!name}}
\permanent\protected\def\doifnotcounter  #1{\clf_doifnotcounter {\namedcounterparameter{#1}\s!name}}

\aliased\let\doifcounterelse\doifelsecounter

\permanent\tolerant\protected\def\setcounter[#1]#*[#2]#*[#3]%
  {\ifarguments\or\or
     \clf_setcounter   {\namedcounterparameter{#1}\s!name}\numexpr#2\relax
   \else
     \clf_setsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\numexpr#3\relax
   \fi}

\permanent\tolerant\protected\def\setcounterown[#1]#*[#2]#*[#3]%
  {\ifarguments\or\or
     \clf_setowncounter   {\namedcounterparameter{#1}\s!name}{#2}%
   \else
     \clf_setownsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax{#3}%
   \fi}

\permanent\tolerant\protected\def\restartcounter[#1]#*[#2]#*[#3]%
  {\ifarguments\or\or
     \clf_restartcounter   {\namedcounterparameter{#1}\s!name}\numexpr#2\relax
   \else
     \clf_restartsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\numexpr#3\relax
   \fi}

\permanent\tolerant\protected\def\resetcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_resetcounter   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_resetsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax
   \fi}

\permanent\tolerant\protected\def\incrementcounter[#1]#*[#2]%
  {\ifarguments\or
     \strc_counters_increment_sub{#1}\plusone
   \else
     \strc_counters_increment_sub{#1}{#2}%
   \fi}

\permanent\tolerant\protected\def\decrementcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_decrementcounter   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_decrementsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax
   \fi}

\permanent\tolerant\protected\def\rawcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_countervalue   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_subcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\lastcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_lastcountervalue   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_lastsubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\firstcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_firstcountervalue   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_firstsubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\prevcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_previouscountervalue   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_previoussubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\nextcounter[#1]#*[#2]%
  {\ifarguments\or
     \clf_nextcountervalue   {\namedcounterparameter{#1}\s!name}%
   \else
     \clf_nextsubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\countersubs[#1]#*[#2]%
  {\ifarguments\or
    \clf_subcountervalues   {\namedcounterparameter{#1}\s!name}%
   \else
    \clf_subsubcountervalues{\namedcounterparameter{#1}\s!name}\numexpr#2\relax\or
   \fi}

\permanent\tolerant\protected\def\savecounter[#1]%
  {\ifarguments\or
     \clf_savecounter{\namedcounterparameter{#1}\s!name}%
   \fi}

\permanent\tolerant\protected\def\restorecounter[#1]%
  {\ifarguments\or
     \clf_restorecounter{\namedcounterparameter{#1}\s!name}%
   \fi}

\protected\def\strc_counters_set            #1#2{\clf_setcounter             {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\protected\def\strc_counters_setown         #1#2{\clf_setowncounter          {\namedcounterparameter{#1}\s!name}{#2}}
\protected\def\strc_counters_restart        #1#2{\clf_restartcounter         {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\protected\def\strc_counters_reset            #1{\clf_resetcounter           {\namedcounterparameter{#1}\s!name}}
\protected\def\strc_counters_decrement        #1{\clf_decrementcounter       {\namedcounterparameter{#1}\s!name}}

          \def\strc_counters_raw              #1{\clf_countervalue           {\namedcounterparameter{#1}\s!name}}
          \def\strc_counters_last             #1{\clf_lastcountervalue       {\namedcounterparameter{#1}\s!name}}
          \def\strc_counters_first            #1{\clf_firstcountervalue      {\namedcounterparameter{#1}\s!name}}
          \def\strc_counters_next             #1{\clf_nextcountervalue       {\namedcounterparameter{#1}\s!name}}
          \def\strc_counters_prev             #1{\clf_previouscountervalue   {\namedcounterparameter{#1}\s!name}}
          \def\strc_counters_subs             #1{\clf_subcountervalues       {\namedcounterparameter{#1}\s!name}}

\protected\def\strc_counters_set_sub      #1#2#3{\clf_setsubcounter          {\namedcounterparameter{#1}\s!name}\numexpr#2\relax\numexpr#3\relax}
\protected\def\strc_counters_setown_sub   #1#2#3{\clf_setownsubcounter       {\namedcounterparameter{#1}\s!name}\numexpr#2\relax{#3}}
\protected\def\strc_counters_restart_sub  #1#2#3{\clf_restartsubcounter      {\namedcounterparameter{#1}\s!name}\numexpr#2\relax\numexpr#3\relax}
\protected\def\strc_counters_reset_sub      #1#2{\clf_resetsubcounter        {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\protected\def\strc_counters_decrement_sub  #1#2{\clf_decrementsubcounter    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}

          \def\strc_counters_raw_sub        #1#2{\clf_subcountervalue        {\namedcounterparameter{#1}\s!name}\numexpr#2\relax} % maybe raw
          \def\strc_counters_last_sub       #1#2{\clf_lastsubcountervalue    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
          \def\strc_counters_first_sub      #1#2{\clf_firstsubcountervalue   {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
          \def\strc_counters_next_sub       #1#2{\clf_nextsubcountervalue    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
          \def\strc_counters_prev_sub       #1#2{\clf_previoussubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
          \def\strc_counters_subs_sub       #1#2{\clf_subsubcountervalues    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}

\protected\def\strc_counters_save             #1{\clf_savecounter            {\namedcounterparameter{#1}\s!name}}
\protected\def\strc_counters_restore          #1{\clf_restorecounter         {\namedcounterparameter{#1}\s!name}}

\protected\def\strc_counters_incremented      #1{\clf_incrementedcounter     {\namedcounterparameter{#1}\s!name}}
\protected\def\strc_counters_decremented      #1{\clf_decrementedcounter     {\namedcounterparameter{#1}\s!name}}

\permanent\protected\def\showcounter       [#1]{\clf_showcounter       {\namedcounterparameter{#1}\s!name}}
\permanent\protected\def\incrementedcounter[#1]{\clf_incrementedcounter{\namedcounterparameter{#1}\s!name}} % no \dosingleargument
\permanent\protected\def\decrementedcounter[#1]{\clf_decrementedcounter{\namedcounterparameter{#1}\s!name}} % no \dosingleargument

% public variants ... beware, for old cases, from now on the value variants are the
% ones that are expandable

\permanent\def\rawcountervalue  [#1]{\clf_countervalue        {\namedcounterparameter{#1}\s!name}}
\permanent\def\lastcountervalue [#1]{\clf_lastcountervalue    {\namedcounterparameter{#1}\s!name}}
\permanent\def\firstcountervalue[#1]{\clf_firstcountervalue   {\namedcounterparameter{#1}\s!name}}
\permanent\def\nextcountervalue [#1]{\clf_nextcountervalue    {\namedcounterparameter{#1}\s!name}}
\permanent\def\prevcountervalue [#1]{\clf_previouscountervalue{\namedcounterparameter{#1}\s!name}}

\permanent\def\rawsubcountervalue  [#1]#*[#2]{\clf_subcountervalue        {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\permanent\def\lastsubcountervalue [#1]#*[#2]{\clf_lastsubcountervalue    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\permanent\def\firstsubcountervalue[#1]#*[#2]{\clf_firstsubcountervalue   {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\permanent\def\nextsubcountervalue [#1]#*[#2]{\clf_nextsubcountervalue    {\namedcounterparameter{#1}\s!name}\numexpr#2\relax}
\permanent\def\prevsubcountervalue [#1]#*[#2]{\clf_previoussubcountervalue{\namedcounterparameter{#1}\s!name}\numexpr#2\relax}

% The bypage check needs a multipass reference and therefore we only check for it when we increment
% and know that some content will be placed. We could also check for spreads.

\protected\def\strc_counters_increment_sub#1#2%
  {% this will be combined into one lua call
   \edef\m_strc_counters_way{\strc_counters_way{#1}}%
   \ifx\m_strc_counters_way\v!page
     \checkpagechange{#1}%
     \ifpagechanged
       \strc_counters_reset{#1}%
     \fi
   \fi
   \clf_incrementsubcounter{\namedcounterparameter{#1}\s!name}\numexpr#2\relax}

\protected\def\strc_counters_increment#1%
  {\strc_counters_increment_sub{#1}\plusone}

% so far for the hack

\permanent\tolerant\protected\def\convertedcounter[#1]#*[#2]%
  {\begingroup
   \cdef\currentcounter{#1}%
   \ifparameter#2\or\setupcurrentcounter[#2]\fi
   \clf_prefixedconverted
     {\counterparameter\s!name}
     {
       prefix        {\counterparameter\c!prefix}
       separatorset  {\counterparameter\c!prefixseparatorset}
       conversion    {\counterparameter\c!prefixconversion}
       conversionset {\counterparameter\c!prefixconversionset}
       starter       {\counterparameter\c!prefixstarter}
       stopper       {\counterparameter\c!prefixstopper}
       set           {\counterparameter\c!prefixset}
       segments      {\counterparameter\c!prefixsegments}
       connector     {\counterparameter\c!prefixconnector}
     }
     {
       order         {\counterparameter\c!numberorder}
       separatorset  {\counterparameter\c!numberseparatorset}
       conversion    {\counterparameter\c!numberconversion}
       conversionset {\counterparameter\c!numberconversionset}
       starter       {\counterparameter\c!numberstarter}
       stopper       {\counterparameter\c!numberstopper}
       segments      {\counterparameter\c!numbersegments}
       type          {\counterparameter\c!type}
       criterium     {\counterparameter\c!criterium}
     }
   \relax
   \endgroup}

\permanent\def\directconvertedcounter#1#2% name, type
  {\clf_prefixedconverted
     {\namedcounterparameter{#1}\s!name}
     {
       prefix        {\namedcounterparameter{#1}\c!prefix}
       separatorset  {\namedcounterparameter{#1}\c!prefixseparatorset}
       conversion    {\namedcounterparameter{#1}\c!prefixconversion}
       conversionset {\namedcounterparameter{#1}\c!prefixconversionset}
    %  starter       {\namedcounterparameter{#1}\c!prefixstarter}
    %  stopper       {\namedcounterparameter{#1}\c!prefixstopper}
       set           {\namedcounterparameter{#1}\c!prefixset}
       segments      {\namedcounterparameter{#1}\c!prefixsegments}
       connector     {\namedcounterparameter{#1}\c!prefixconnector}
     }
     {
       order         {\namedcounterparameter{#1}\c!numberorder}
       separatorset  {\namedcounterparameter{#1}\c!numberseparatorset}
       conversion    {\namedcounterparameter{#1}\c!numberconversion}
       conversionset {\namedcounterparameter{#1}\c!numberconversionset}
       starter       {\namedcounterparameter{#1}\c!numberstarter}
       stopper       {\namedcounterparameter{#1}\c!numberstopper}
       segments      {\namedcounterparameter{#1}\c!numbersegments}
       type          {#2}
     }
   \relax}

\permanent\tolerant\protected\def\convertedsubcounter[#1]#*[#2]#*[#3]% #2 can be n or n:m
  {\ifarguments\or
     \convertedcounter[#1][]%
   \else
     \convertedcounter[#1][\c!numbersegments=#2,#3]%
   \fi}

\permanent\protected\def\doifdefinedcounter    {\doifcommandhandler    \??counter}
\permanent\protected\def\doifundefinedcounter  {\doifnotcommandhandler \??counter}
\permanent\protected\def\doifelsedefinedcounter{\doifelsecommandhandler\??counter}

\aliased\let\doifdefinedcounterelse\doifelsedefinedcounter

%D What follows is a compatibility layer. Do we need this?

\aliased\let \numberparameter       \namedcounterparameter  % {name}\c!key

\aliased\let \definenumber          \definecounter          % [name]
\aliased\let \setupnumber           \setupcounter           % [name][setups]

\aliased\let \setnumber             \setcounter             % [name]{value}
\aliased\let \resetnumber           \resetcounter           % [name]
\aliased\let \savenumber            \savecounter            % [name]
\aliased\let \restorenumber         \restorecounter         % [name]
\aliased\let \incrementnumber       \incrementcounter       % [name]
\aliased\let \decrementnumber       \decrementcounter       % [name]
\aliased\let \rawnumber             \rawcounter             % [name]
\aliased\let \getnumber             \convertedcounter       % [name]
\aliased\let \convertednumber       \convertedcounter       % [name]

\aliased\let \doifdefinednumber     \doifdefinedcounter     % {number}{true}
\aliased\let \doifelsedefinednumber \doifelsedefinedcounter % {number}{true}{false}
\aliased\let \doifdefinednumberelse \doifelsedefinedcounter % {number}{true}{false}

\aliased\let \setupnumbering        \setupcounter

%D Helpers:

% call:
%
% \strc_counters_register_component
%   \currentfloat
%   \getfloatparameters \floatparameter \detokenizedfloatparameter
%   \hascaption \hastitle \hasnumber
%   [settings][userdata]
%
% sets:
%
% \m_strc_counters_last_registered_index
% \m_strc_counters_last_registered_attribute
% \m_strc_counters_last_registered_synchronize

% currentstructurecomponent => \strc_current_ or just \m_strc_

\mutable\lettonothing\currentname
\mutable\lettonothing\currentcounter

\protected\def\strc_counters_register_component#1#2#3#4#5#6#7[#8][#9]% maybe also nolist
  {\begingroup
   %
   #2[\s!haslevel=1,#8]%
   \edef\p_haslevel  {#3\s!haslevel}%
   \edef\p_hascaption{#3\s!hascaption}%
   \edef\p_hastitle  {#3\s!hastitle}%
   \edef\p_hasnumber {#3\s!hasnumber}%
   %
   \edef\p_prefixsegments{#3\c!prefixsegments}%
   \ifx\p_prefixsegments\v!auto
     \edef\p_prefixsegments{\autostructureprefixsegments#3}%
   \fi
   %
   \edef\currentname{#3\s!name}%
   \ifempty\currentname
     \edef\currentname{#1}%
   \fi
   \cdef\currentcounter{#3\s!counter}%
   \ifempty\currentcounter
     \let\currentcounter\currentname
   \fi
   %
   \ifx\p_hascaption\v!yes
     \strc_counters_register_component_list{#1}{#3}{#4}{#9}%
   \orelse\ifempty\currentstructurecomponentreference
     \strc_counters_register_component_none
   \else
     \strc_counters_register_component_page{#3}%
   \fi
   \endgroup}

\def\strc_counters_register_component_none
  {\glet\m_strc_counters_last_registered_index      \relax
   \glet\m_strc_counters_last_registered_attribute  \attributeunsetvalue
   \glet\m_strc_counters_last_registered_synchronize\relax}

\def\strc_counters_register_component_check_prefix
  {\ifempty\currentstructurecomponentreferenceprefix
     \let\currentstructurecomponentreferenceprefix\currentstructurereferenceprefix
   \fi
   \ifempty\currentstructurecomponentreferenceprefix
     \let\currentstructurecomponentreferenceprefix\referenceprefix
   \fi
   \ifdefined\currentstructurecomponentreferenceprefix\else
     \lettonothing\currentstructurecomponentreferenceprefix
   \fi}

\def\strc_counters_register_component_page#1%
  {\xdef\currentstructurecomponentreference      {#1\c!reference}%
   \xdef\currentstructurecomponentreferenceprefix{#1\c!referenceprefix}%
   \strc_counters_register_component_check_prefix
   \setnextinternalreference
   \clf_setdestinationattribute
        {%
            references {%
                  internal  \locationcount
                % block     {\currentsectionblock}% move to lua
                  view      {\interactionparameter\c!focus}%
                  prefix    {\currentstructurecomponentreferenceprefix}%
                  reference {\currentstructurecomponentreference}%
            }%
            metadata {%
                kind {\s!page}%
            }%
        }%
   \relax
   \xdef\m_strc_counters_last_registered_attribute  {\the\lastdestinationattribute}%
   \glet\m_strc_counters_last_registered_index      \relax
   \glet\m_strc_counters_last_registered_synchronize\relax}

\def\strc_counters_register_component_list#1#2#3#4%
  {\xdef\currentstructurecomponentname           {#2\s!name}%
   \xdef\currentstructurecomponentcounter        {#2\s!counter}%
   \xdef\currentstructurecomponentlevel          {#2\s!haslevel}%
   \edef\currentstructurecomponentexpansion      {#2\c!expansion}%
   \xdef\currentstructurecomponentxmlsetup       {#2\c!xmlsetup}%
   \xdef\currentstructurecomponentcatcodes       {#2\s!catcodes}%
   \xdef\currentstructurecomponentlabel          {#2\c!label}%
   \xdef\currentstructurecomponentreference      {#2\c!reference}%
   \xdef\currentstructurecomponentreferenceprefix{#2\c!referenceprefix}%
   \ifempty\currentstructurecomponentcounter
      \glet\currentstructurecomponentcounter\currentcounter
   \fi
   \strc_counters_register_component_check_prefix
   \ifx\currentstructurecomponentexpansion\s!xml
     \xmlstartraw
       \xdef\currentstructurecomponenttitle   {#2\c!title}%
       \xdef\currentstructurecomponentbookmark{#2\c!bookmark}%
       \xdef\currentstructurecomponentmarking {#2\c!marking}%
       \xdef\currentstructurecomponentlist    {#2\c!list}%
     \xmlstopraw
     \ifempty\currentstructurecomponentlist
       \glet\currentstructurecomponentlist\currentstructurecomponenttitle
     \fi
     \glet\currentstructurecomponentcoding\s!xml
   \else
     \ifx\currentstructurecomponentexpansion\v!yes
       \xdef\currentstructurecomponenttitle   {#2\c!title}%
       \xdef\currentstructurecomponentbookmark{#2\c!bookmark}%
       \xdef\currentstructurecomponentmarking {#2\c!marking}%
       \xdef\currentstructurecomponentlist    {#2\c!list}%
     \else
       \xdef\currentstructurecomponenttitle   {#3\c!title}%
       \xdef\currentstructurecomponentbookmark{#3\c!bookmark}%
       \xdef\currentstructurecomponentmarking {#3\c!marking}%
       \xdef\currentstructurecomponentlist    {#3\c!list}%
       \iflocation \ifempty\currentstructurecomponentbookmark
         \begingroup
         \simplifycommands
         \xdef\currentstructurecomponentbookmark{\detokenize\expandafter{\normalexpanded{#2\c!title}}}%
        \endgroup
       \fi \fi
     \fi
     \ifempty\currentstructurecomponentlist
       \glet\currentstructurecomponentlist\currentstructurecomponenttitle
     \fi
     \glet\currentstructurecomponentcoding\s!tex
   \fi
   %
   \setnextinternalreference
   \scratchcounter\clf_addtolist %{
      metadata {
          kind     {#1}
          name     {\currentname}
        % level    structures.sections.currentlevel()
          catcodes \ifempty\currentstructurecomponentcatcodes\catcodetable\else\csname\currentstructurecomponentcatcodes\endcsname\fi
          coding   {\currentstructurecomponentcoding}
      \ifx\currentstructurecomponentcoding\s!xml
          xmlroot  {\xmldocument}
      \fi
      \ifempty\currentstructurecomponentxmlsetup \else
          xmlsetup {\currentstructurexmlsetup}
      \fi
      }
      references {
          internal  \locationcount
        % block     {\currentsectionblock}
          reference {\currentstructurecomponentreference}
          prefix    {\currentstructurecomponentreferenceprefix}
        % section   structures.sections.currentid()
          view      {\interactionparameter\c!focus}%
      }
      titledata {
          label    {\detokenize\expandafter{\currentstructurecomponentlabel}}
          title    {\detokenize\expandafter{\currentstructurecomponenttitle}}
      \ifx\currentstructurecomponentbookmark\currentstructurecomponenttitle \else
          bookmark {\detokenize\expandafter{\currentstructurecomponentbookmark}}
      \fi
      \ifx\currentstructurecomponentmarking\currentstructurecomponenttitle \else
          marking  {\detokenize\expandafter{\currentstructurecomponentmarking}}
      \fi
      \ifx\currentstructurecomponentlist\currentstructurecomponenttitle \else
          list     {\detokenize\expandafter{\currentstructurecomponentlist}}
      \fi
      }
  \ifx\p_hasnumber\v!yes\ifempty\currentstructurecomponentcounter\else
      prefixdata {
          prefix        {#2\c!prefix}
          separatorset  {#2\c!prefixseparatorset}
          conversion    {#2\c!prefixconversion}
          conversionset {#2\c!prefixconversionset}
          set           {#2\c!prefixset}
       %  segments      {#2\c!prefixsegments}
          segments      {\p_prefixsegments}
          connector     {#2\c!prefixconnector}
      }
      numberdata { % more helpers here, like compact elsewhere
        \ifempty\currentstructurecomponentlevel\else
          level         \currentstructurecomponentlevel
        \fi
          numbers       {\currentstructurecomponentcounter}
          group         {#2\c!group}
          groupsuffix   {#2\c!groupsuffix}
          counter       {\currentstructurecomponentcounter}
          separatorset  {#2\c!numberseparatorset}
          conversion    {#2\c!numberconversion}
          conversionset {#2\c!numberconversionset}
          starter       {#2\c!numberstarter}
          stopper       {#2\c!numberstopper}
          segments      {#2\c!numbersegments}
      }
  \fi\fi
      userdata {\detokenize{#4}}
   %}
   \relax
   \xdef\m_strc_counters_last_registered_index{\the\scratchcounter}%
   \setstructurecomponentsynchronization\m_strc_counters_last_registered_index
   \glet\m_strc_counters_last_registered_attribute  \currentstructurecomponentattribute
   \glet\m_strc_counters_last_registered_synchronize\currentstructurecomponentsynchronize}

\let\m_strc_counters_last_registered_index      \relax
\let\m_strc_counters_last_registered_attribute  \relax
\let\m_strc_counters_last_registered_synchronize\relax

% This can be improved as we don't need to pas all these variables
% each time (we can set them up once).

\protected\def\strc_counter_preset_using_parameter#1#2% \setupcommand \someparameter
  {#1%
    [\c!way                =#2\c!way,
     \c!prefix             =#2\c!prefix,
     \c!prefixseparatorset =#2\c!prefixseparatorset,
     \c!prefixconversion   =#2\c!prefixconversion,
     \c!prefixconversionset=#2\c!prefixconversionset,
     \c!prefixstarter      =#2\c!prefixstarter,
     \c!prefixstopper      =#2\c!prefixstopper,
     \c!prefixsegments     =#2\c!prefixsegments,
     \c!prefixset          =#2\c!prefixset,
     \c!prefixconnector    =#2\c!prefixconnector,
     \c!numberseparatorset =#2\c!numberseparatorset,
     \c!numberconversion   =#2\c!numberconversion,
     \c!numberconversionset=#2\c!numberconversionset,
     \c!numberstarter      =#2\c!numberstarter,
     \c!numberstopper      =#2\c!numberstopper,
     \c!numbersegments     =#2\c!numbersegments]}

\protected\def\strc_counter_setup_using_parameter#1#2% name \someparameter
  {\cdef\currentcounter{#1}%
   %
   \setcounterparameter              \c!start{#2\c!start}%
   \setcounterparameter              \c!state{#2\c!state}% % beware, "" == start
   \setcounterparameter                \c!way{#2\c!way}%
   %
   \setcounterparameter             \c!prefix{#2\c!prefix}%
   \setcounterparameter \c!prefixseparatorset{#2\c!prefixseparatorset}%
   \setcounterparameter   \c!prefixconversion{#2\c!prefixconversion}%
   \setcounterparameter\c!prefixconversionset{#2\c!prefixconversionset}%
   \setcounterparameter      \c!prefixstarter{#2\c!prefixstarter}%
   \setcounterparameter      \c!prefixstopper{#2\c!prefixstopper}%
   \setcounterparameter          \c!prefixset{#2\c!prefixset}%
   \setcounterparameter     \c!prefixsegments{#2\c!prefixsegments}%
   \setcounterparameter          \c!prefixset{#2\c!prefixset}%
   \setcounterparameter    \c!prefixconnector{#2\c!prefixconnector}%
   %
   \setcounterparameter \c!numberseparatorset{#2\c!numberseparatorset}%
   \setcounterparameter   \c!numberconversion{#2\c!numberconversion}%
   \setcounterparameter\c!numberconversionset{#2\c!numberconversionset}%
   \setcounterparameter      \c!numberstarter{#2\c!numberstarter}%
   \setcounterparameter      \c!numberstopper{#2\c!numberstopper}%
   \setcounterparameter     \c!numbersegments{#2\c!numbersegments}%
   %
   \the\everysetupcounter}

\protected\def\mult_interfaces_counter_association#1#2#3#4#5#6#7% tag current setup parameter list sync register
  {\strc_counter_preset_using_parameter#3\rootcounterparameter
   \newtoks#5%
   \permanent\protected\def   #6{\ifempty#2\the#5\else\strc_counter_setup_using_parameter#2#4\fi}% sync
   \permanent\protected\def#7##1{\normalexpanded{#5{\the#5\strc_counter_setup_using_parameter{##1}\noexpand#4}}}} % register

\permanent\protected\def\installcounterassociation#1% => synchronize#1counters register#1counter
  {\normalexpanded
     {\mult_interfaces_counter_association
        {#1}% not \??xx but xx
        \expandafter\noexpand\csname current#1\endcsname
        \expandafter\noexpand\csname setup#1\endcsname
        \expandafter\noexpand\csname #1parameter\endcsname
        \expandafter\noexpand\csname counter_association_list_#1\endcsname
        \expandafter\noexpand\csname synchronize#1counters\endcsname
        \expandafter\noexpand\csname register#1counter\endcsname}}

% needs testing:
%
% \protected\def\strc_counter_setup_push#1#2#3% \someparameter \directsomeparameter \setexpandedsomeparameter
%   {\let\savedcounterparameter           \counterparameter
%    \let\saveddirectcounterparameter     \directcounterparameter
%    \let\savedsetexpandedcounterparameter\setexpandedcounterparameter
%    % remap
%    \let\counterparameter                #1%
%    \let\directcounterparameter          #2%
%    \let\setexpandedcounterparameter     #3}
%
% \protected\def\strc_counter_setup_pop
%   {\let\counterparameter                \savedcounterparameter
%    \let\directcounterparameter          \saveddirectcounterparameter
%    \let\setexpandedcounterparameter     \savedsetexpandedcounterparameter}
%
% \protected\def\mult_interfaces_counter_association#1#2#3#4#5#6#7% tag current setup parameter list sync register
%   {\strc_counter_preset_using_parameter#3\rootcounterparameter
%    \newtoks#5%
%    \protected\def#6% sync
%      {\strc_counter_setup_push
%       \ifempty#2%
%         \the#5%
%       \else
%         \lettonothing\currentcounter
%         \the\everysetupcounter
%       \fi
%       \strc_counter_setup_pop}%
%    \protected\def#7##1% register
%       {\normalexpanded{#5{\the#5\edef\noexpand\currentcounter{##1}\noexpand\the\everysetupcounter}}}}

%D For good old times (easier to explain in manuals):
%D
%D \starttyping
%D \setcounter[userpage][9]
%D \setupcounter[userpage][number=9]
%D \setupuserpagenumber[number=9]
%D \stoptyping

% needs testing: we might have conflicts with mixins
%
% \appendtoks
%     \ifempty\currentcounter \else
%         \edef\p_number{\counterparameter\c!number}%
%         \ifempty\p_number \else
%             \strc_counters_set\currentcounter\p_number
%             \resetcounterparameter\c!number
%         \fi
%     \fi
% \to \everysetupcounter

\stopcontextdefinitioncode

\protect \endinput