%D \module
%D   [       file=core-dat,
%D        version=20122.04.17, % replaces core-two from 1997.03.31,
%D          title=\CONTEXT\ Core Macros,
%D       subtitle=Multipass Datasets,
%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 Core Macros / Multipass Datasets}

%D \starttyping
%D \definedataset[test-1]
%D \definedataset[test-2][delay=yes]
%D
%D \startlines
%D set 1: \setdataset[test-1][whatever=this-or-that-1]
%D set 2: \setdataset[test-2][whatever=this-or-that-2]
%D set 3: \setdataset[test-2][whatever=this-or-that-3]
%D \stoplines
%D
%D \startlines
%D get 1: \datasetvariable{test-1}{1}{whatever} / \datasetvariable{test-1}{1}{realpage}
%D get 2: \datasetvariable{test-2}{1}{whatever} / \datasetvariable{test-2}{1}{realpage}
%D get 3: \datasetvariable{test-2}{2}{whatever} / \datasetvariable{test-2}{2}{realpage}
%D \stoplines
%D \stoptyping

\unprotect

\registerctxluafile{core-dat}{}

\installcorenamespace{dataset}

\installcommandhandler \??dataset {dataset} \??dataset

\unexpanded\def\setdataset
  {\dotripleempty\syst_datasets_set}

\def\syst_datasets_set
  {\ifthirdargument
     \expandafter\syst_datasets_set_named
   \else
     \expandafter\syst_datasets_set_indexed
   \fi}

\def\syst_datasets_set_named[#1][#2][#3]%
  {\begingroup
   \edef\currentdataset{#1}%
   \clf_setdataset
      name  {\currentdataset}%
      tag   {#2}%
      delay {\datasetparameter\c!delay}%
      data  {#3}%
   \relax
   \endgroup}

\def\syst_datasets_set_indexed[#1][#2][#3]%
  {\begingroup
   \edef\currentdataset{#1}%
   \clf_setdataset
      name  {\currentdataset}%
      delay {\datasetparameter\c!delay}%
      data  {#2}%
   \relax
   \endgroup}

\def\datasetvariable#1#2#3%
  {\clf_datasetvariable{#1}{#2}{#3}}

\installcorenamespace{pagestate}
\installcorenamespace{pagestatecounter}

\installcommandhandler \??pagestate {pagestate} \??pagestate

\def\syst_pagestates_allocate
  {\expandafter\newcount\csname\??pagestatecounter\currentpagestate\endcsname
   \expandafter\let\expandafter\c_syst_pagestate\csname\??pagestatecounter\currentpagestate\endcsname}

\appendtoks
    \syst_pagestates_allocate
\to \everydefinepagestate

\setuppagestate
  [\c!delay=\v!yes]

\unexpanded\def\setpagestate
  {\dodoubleempty\syst_pagestates_set}

\def\syst_pagestates_set[#1][#2]%
  {\begingroup
   \edef\currentpagestate{#1}%
   \ifcsname\??pagestatecounter\currentpagestate\endcsname
     \let\c_syst_pagestate\lastnamedcs
   \else
     \syst_pagestates_allocate
   \fi
   \global\advance\c_syst_pagestate\plusone
   \scratchcounter\lastnamedcs
   \clf_setpagestate
      name  {\currentpagestate}%
      tag   {\ifsecondargument#2\else\number\c_syst_pagestate\fi}%
      delay {\pagestateparameter\c!delay}%
   \relax
   \endgroup}

\unexpanded\def\autosetpagestate#1%
  {\secondargumentfalse\syst_pagestates_set[#1]}

\def\autopagestatenumber#1{\begincsname\??pagestatecounter#1\endcsname}

\def\pagestaterealpage     #1#2{\clf_pagestaterealpage     {#1}{#2}}
\def\setpagestaterealpageno#1#2{\clf_setpagestaterealpageno{#1}{#2}}
\def\pagestaterealpageorder#1#2{\clf_pagestaterealpageorder{#1}#2\relax}

\def\autopagestaterealpage     #1{\clf_pagestaterealpage     {#1}{\number\autopagestatenumber{#1}}}
\def\setautopagestaterealpageno#1{\clf_setpagestaterealpageno{#1}{\number\autopagestatenumber{#1}}}
\def\autopagestaterealpageorder#1{\clf_pagestaterealpageorder{#1}\numexpr\autopagestatenumber{#1}\relax}

\protect