%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Module: ZzTeX Cross-Referencing Facilities
%
% Synopsis:
%
% Author: Paul C. Anagnostopoulos
% Created: 19 September 1989
%
% Copyright 1989--2020 by Paul C. Anagnostopoulos
% under The MIT License (opensource.org/licenses/MIT)
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Data Structures
% ---- ----------
\definewrite{\zxrootfile}
\definewrite{\zxdivfile}
\setflag \zxdivopen = \false
\definewrite{\zxcompfile}
\setflag \zxcompavail = \false
\chardef \xrefbadmode = 0 % Invalid mode.
\chardef \xrefrunmode = 1 % Normal running environment.
\chardef \xrefsnapmode = 2 % Taking a division snapshot.
\chardef \xrefcopymode = 3 % Copying cross-reference files.
\chardef \xrefloadmodes = 4 % Beginning of load modes:
\chardef \xrefloadtagmode = 5 % Load tag definitions.
\chardef \xrefloadtocmode = 6 % Load table of contents.
\chardef \xrefloadauxmode = 7 % Create BibTeX auxiliary file.
\chardef \xrefloadendmode = 8 % Load endnotes.
\chardef \xrefloadcitemode = 9 % Load citation folios.
\let \xrefmode = \xrefbadmode % Default mode.
% Comment Lines
% ------- -----
{\catcode`\%=\catother
\gdef \zcomment {%\space}
} % \catcode
\def \zxwritecomment #1#2#3{% {file}{keyword}{values}
\immediate\write #1 {\zcomment #2: #3}}
% Initialization
% --------------
\def \zxrefinit {%
\zxcompinit
\zxopenroot
\let \xrefmode = \xrefrunmode}
\def \zxcompinit {%
\checkfile{\zxcompavail}{\jobname.zzc}%
\if \zxcompavail
\zxloadcomp{\xrefloadtagmode}%
\else
\checkfile{\zxcompavail}{\jobname.zzx}%
\if \zxcompavail
\zxgencomp
\zxloadcomp{\xrefloadtagmode}%
\else
\remark{There is no cross-reference file available for this run.}%
\fi
\fi}
\def \zxopenroot {%
\immediate\openout \zxrootfile = \jobname.zzx\relax
\zxwritecomment{\zxrootfile}{root}{\jobname}}
% Division Handling
% -------- --------
\def \zxdivinit #1#2{% {division-name}{setting-it?}
\immediate\write \zxrootfile {\noexpand\zinputzzx{#1}}%
\if #2%
\immediate\openout \zxdivfile = #1.zzx\relax
\global\setflag \zxdivopen = \true
\zxwritecomment{\zxdivfile}{division}{#1}%
\immediate\write \zxdivfile
{\noexpand\xref{div}{}{}{}{\the\divisionname}\zcomment}%
\fi}
% There is nothing to do with each entry in the cross-reference file.
\def \xrefdiv #1#2#3#4{}
\def \zxdivfinal #1{%
\if \zxdivopen
\ztakesnap
\zxwritecomment{\zxdivfile}{end}{#1}%
\immediate\closeout \zxdivfile
\global\setflag \zxdivopen = \false
\fi}
% Finalization
% ------------
\def \zxreffinal {%
\zxwritecomment{\zxrootfile}{end}{\jobname}%
\immediate\closeout \zxrootfile
\zxgencomp}
% Generate Composite File
% -------- --------- ----
\def \zxgencomp {%
\remark{Generating composite cross-reference file:}%
\immediate\openout \zxcompfile = \jobname.zzc\relax
\zxwriteinfo{\true}{jobname}{\jobname}{}%
\zxwriteinfo{\true}{time}{\number\year.\number\month.\number\day}{\formattime}%
\zxwriteinfo{\true}{version}{\ZzTeXversion}{}%
\zxwriteinfo{\true}{author}{\bookauthor}{}%
\zxwriteinfo{\true}{title}{\booktitle}{}%
\zxwriteinfo{\true}{publisher}{\bookpublisher}{}%
\zxwriteinfo{\true}{ISBN}{\bookISBN}{}%
\zxwriteinfo{\true}{art-root}{\zartroot}{}%
\zxwriteinfo{\true}{place-art}{\zplaceart}{}%
\zxwriteinfo{\true}{PDF-hyperlinks}{\PDFhyperlinks}{}%
\zxwriteinfo{\true}{proof}{\the\zproofid}{}%
\zxwriteinfo{\true}{compositor}{\ininame}{\iniorganization}%
\zxwriteinfo{\true}{trim}{\the\trimwidth}{\the\trimheight}%
\zxwriteinfo{\true}{head-margin}{\the\headmargin}{}%
\zxwriteinfo{\true}{inner-margin}{\the\eveninnermargin}{\the\oddinnermargin}%
\let \zxmodesave = \xrefmode
\let \xrefmode = \xrefcopymode
\input \jobname.zzx\relax
\let \xrefmode = \zxmodesave
\zxwritecomment{\zxcompfile}{end}{\jobname}%
\immediate\closeout \zxcompfile}
% This macro writes an information entry in the composite cross-reference
% file.
\def \zxwriteinfo #1#2#3#4{% {composite?}{key}{value1}{value2}
\if #1%
\immediate\write \zxcompfile {\noexpand\xref{info}{}{#2}{#3}{#4}\zcomment}%
\else
\zbeginhidewrite
\edef \znext {\noexpand\xref{info}{\noexpand\folio}%
{#2}%
{#3}
{#4}}%
\znext
\zendhidewrite
\fi}
%%% \immediate\write #1{\noexpand\xref{info}{#2}{#3}{#4}{\noexpand\folio}\zcomment}}
% There is nothing to do when info entries are executed.
\def \xrefinfo #1#2#3#4{}
% This macro is used in the root cross-reference file to suck in the
% division cross-reference files.
\def \zinputzzx #1{%
\checkfile{\znext}{#1.zzx}%
\if \znext \input #1.zzx \fi}
% Load Composite File
% ---- --------- ----
\def \zxloadcomp #1{% {xref-mode}
\if \zxcompavail
\let \zxmodesave = \xrefmode
\let \xrefmode =#1%
\input \jobname.zzc\relax
\let \xrefmode = \zxmodesave
\fi}
\def \zxloadothercomp #1#2{% {file}{xref-mode}
\let \zxmodesave = \xrefmode
\let \xrefmode = #2%
\input #1\relax
\let \xrefmode = \zxmodesave}
\def \loadrelatedxref #1{% {file}
\zxloadothercomp{#1}{\xrefloadtagmode}}
% Cross-Reference Macro
% --------------- -----
% Here's how the arguments are treated in each of the modes:
%
% Mode type page arg3 title arg5
%
% load expanded --- passed to appropriate \xrefxxx macro ---
% copy expanded expanded expanded unexpanded expanded
% run expanded unexpanded expanded unexpanded expanded
% snap expanded expanded expanded expanded expanded
% This macro is written for speed.
\long\def \xref #1#2#3#4#5{% {type}{page-number}{arg3}{title}{arg5}
\ifnum \xrefmode>\xrefloadmodes
\name{\xref#1}{#2}{#3}{#4}{#5}%
\else\ifnum \xrefmode=\xrefcopymode
{\def \zxtitle {#4}%
\immediate\write \zxcompfile {\noexpand\xref{#1}{#2}{#3}%
{\expandafter\zdefof \meaning\zxtitle\zmark}{#5}\zcomment}}%
\name{\xref#1}{#2}{#3}{#4}{#5}% In case they want to do something.
\else\ifnum \xrefmode=\xrefrunmode
{\def \zxtitle {#4}%
\edef \znext {\noexpand\noexpand\noexpand\xref
{#1}{\noexpand#2}{#3}%
{\expandafter\zdefof \meaning\zxtitle\zmark}{#5}}%
\expandafter\zxwrite\expandafter{\znext\zcomment}}%
\if \vmodep \repeatpenalty \fi % In case glue follows write.
\else\ifnum \xrefmode=\xrefsnapmode
\immediate\zxwrite{\noexpand\xref{#1}{#2}{#3}{#4}{#5}\zcomment}%
\else
\zxnomode
\fi\fi\fi\fi}
\def \zxwrite {%
\if \zxdivopen \write \zxdivfile \else \write \zxrootfile \fi}
\def \zxnomode {%
\zzerror{No cross-reference mode is set}}
% Page Hints
% ---- -----
\def \pagehint #1{%
\xref{hint}{\noexpand\folio}{}{#1}{}}
% There is nothing to do when hint entries are executed.
\def \xrefhint #1#2#3#4{}