%-*-tex-*-
% Copyright Michael J. Ferguson, INRS-Telecommunications
% All rights reserved. 


% ========== Section, Chapter Headings  ===========
% These macros have several parts,
%       -- The format of the heading. 
%       -- The automatic numbering.
%       -- The writing of a list file for automatic table of contents.
%       -- The referencing in the text ... ie reference number styles.


% ======== Counter allocation and Number styles =========
%========= Autonumbering allocations and styles for sections ... ====
% Allocate the counters for the chapters, sections, figures, etc.
% These counters are updated globally.
\newcount\chnum  %\chnum=0   \def\chnumform{\the\chnum}
\newcount\shnum  %\shnum=0   \def\shnumform{\the\shnum}
\newcount\sshnum %\sshnum=0   \def\sshnumform{\the\sshnum}
\newcount\ssshnum  %\ssshnum=0 \def\ssshnumform{\the\ssshnum}

% ======== autonumbering options and styles ==========
% The following stay unchanged for different numbering options
\def\chtagrefformat{\chnumform}
\def\chtagreplaceformat{\Chapter \chtagrefformat}

\def\numberbychapter{\s@pecialnumberresetlevel=2
  \def\shtagreplaceformat{\shtagrefformat}
  \def\sshtagreplaceformat{\sshtagrefformat}
  \def\ssshtagreplaceformat{\ssshtagrefformat}
  \def\shtagrefformat{\chnumform.\shnumform}               %section
  \def\sshtagrefformat{\chnumform.\shnumform.\sshnumform}  %subsection
  \def\ssshtagrefformat{\chnumform.\shnumform.\sshnumform  %subsubsection
                     .\ssshnumform}
  \def\Prerefform{\chnumform.} 
  \def\Postrefform{}}

\def\numberbysection{\s@pecialnumberresetlevel=3
  \def\shtagreplaceformat{\shtagrefformat.}
  \def\sshtagreplaceformat{\sshtagrefformat}
  \def\ssshtagreplaceformat{\ssshtagrefformat}
  \def\shtagrefformat{\shnumform}                          %section
  \def\sshtagrefformat{\shnumform.\sshnumform}             %subsection
  \def\ssshtagrefformat{\shnumform.\sshnumform             %subsubsection
                     .\ssshnumform}
  \def\Prerefform{\shnumform.}
  \def\Postrefform{}}

\def\specialnumberscontinuous{\def\Prerefform{}
                              \def\Postrefform{}
                              \s@pecialnumberresetlevel=1}


% This macro resets the counters for equations, figures, etc.
% depending on the header level.
%  #1 - header level 1=chapter
%                    2=section
%                    3=subsection
%                    4=subsubsection
%       \a@utonumberresetlevel = 1 sequential numbering
%                               2 chapter numbering
%                               3 section numbering
%                               4 subsection numbering, etc.
\newcount\s@pecialnumberresetlevel \s@pecialnumberresetlevel=1
\def\updatespecialnumbers#1{
    \ifnum #1 < \s@pecialnumberresetlevel
        \the\s@presetlist
    \fi}


% ============ Section head format styles and List generation =======
%
% The calling format is
% \s<ss>head{<number>}{<Title>}
%   Subsequent lines are indented one quad more than the size of the <number>
% There is an autonumbering/autoreferencing feature in these macros. 
% If the autonumber switch
% is true, then the first argument represents a tag instead of a number.

% \nosheadbreak is used when multiple heads start a section
\newif\ifs@headbreak \s@headbreaktrue
\def\nosheadbreak{\s@headbreakfalse}


% ========= Section heading command forms ========
%   #1 top skip
%   #2 bottom skip
%   #3 font
%   #4 <number>
%   #5 <text>
%   #6 table of contents command form
%   #7 <item>, placed between <number> and <text>

\newskip\prsheadskip %\prsheadskip= 6ex plus 2ex minus 2ex
\newskip\posheadskip %\posheadskip= 2ex 
\newskip\prssheadskip % \prssheadskip= 5ex plus 1.8ex minus 1.8ex
\newskip\possheadskip  %\possheadskip= 2ex
\newskip\prsssheadskip %\prsssheadskip= 3ex  plus 1ex minus 1ex
\newskip\posssheadskip %\posssheadskip= 2ex
\newskip\prdsssheadskip %\prdsssheadskip= 3ex  plus 1ex minus 1ex
\newskip\podsssheadskip %\podsssheadskip= 2ex

%this is the format form for those that want to perform radical surgery
%the parameters must be as shown and will have that meaning
% #1 font (=#3); #2 number (=#4) ; #3 <text> (=#5); #4 number/text sep (=#7)
% check on \t@agtext suppresses space when there is no number 
\def\gensheadformat#1#2#3#4{\ifx\t@agtext\empty\setbox0=\hbox{}\else
                                \setbox0=\hbox{#1#2#4}\fi
                \vbox{\veryraggedright \normalbaselines
                      \hangindent 1\wd0 \hangafter 1\noindent #1\unhbox0 #3}}


\def\g@head#1#2#3#4#5#6#7{\ifs@headbreak \goodbreak \vskip #1\else
                                \removelastskip\fi
                \s@headbreaktrue
                \toks0={#5}%prevents expansion inside title
                \writeterm{<#4}{ }{\the\toks0>}
                \gensheadformat{#3}{#4}{#5}{#7}
                \nobreak
                \writelistfile{toc}{#6}{#4}{#5}
                \vskip #2 \vskip -\parskip}

\newtoks\sectionname \newtoks\sectionnumtag
\def\sheadmark{\mark{\the\sectionname}} % defaults to title
\def\innershead #1#2{\sectionnumtag = {#1} \sectionname = {#2}
                       \ifautonumber 
                         \global\advance \shnum by 1 
                         \global\sshnum=0
                         \global\ssshnum=0
                         \updatespecialnumbers{2}
                         \newtag{#1}{\shtagrefformat}
                         \edef\t@agtext{\shtagreplaceformat}
                       \else
                         \edef\t@agtext{#1}
                       \fi
                       \sheadmark        %sections are marked for header titles
                       \g@head{\prsheadskip}{\posheadskip
                                }{\sheadfont}{\t@agtext}{#2}{\shtocout
                                }{\quad}}
\def\innersshead #1#2{\ifautonumber
                         \global\advance \sshnum by 1
                         \global\ssshnum=0
                         \updatespecialnumbers{3}
                         \newtag{#1}{\sshtagrefformat}
                         \edef\t@agtext{\sshtagreplaceformat}
                       \else
                         \edef\t@agtext{#1}
                       \fi
                       \g@head{\prssheadskip}{\possheadskip
                                }{\ssheadfont}{\t@agtext}{#2}{\sshtocout
                                }{\quad}}
\def\innerssshead #1#2{\ifautonumber 
                         \global\advance \ssshnum by 1
                         \updatespecialnumbers{4}
                         \newtag{#1}{\ssshtagrefformat}
                         \edef\t@agtext{\ssshtagreplaceformat}
                       \else
                         \edef\t@agtext{#1}
                       \fi
                       \g@head{\prsssheadskip}{\posssheadskip
                                }{\sssheadfont}{\t@agtext}{#2}{\ssshtocout
                                }{\quad}}
\def\innerdssshead #1{\g@head{\prdsssheadskip}{\podsssheadskip
                       }{\dsssheadfont}{}{#1}{\dssshtocout}{}}
\outer\def\shead#1#2{\innershead{#1}{#2}}
\outer\def\sshead#1#2{\innersshead{#1}{#2}}
\outer\def\ssshead#1#2{\innerssshead{#1}{#2}}
\outer\def\dssshead#1{\innerdssshead{#1}}

%  ======== chead ==========
% The chapter head has a different format entirely 
\newtoks\chaptername

%this is the form of the present chapter head 
%parameters are #1 is the title text \cheadfont, \chtagreplaceformat

%\def\Chapter{Chapter } see English/french titles

% indicates if chapters exist ... default is that they do not
% the first call to a \chead sets it true ... or it may be done in the style.
\newif\ifnochapter %\nochaptertrue


\def\cheadformat#1#2{\vglue 2.5cm
                     \line{$\vcenter{\hbox{\cheadfont
                                          #1
                                          \vrule height 3ex depth 1ex width 0pt
                                          }}\hss
                            \vcenter{\halign{&\cheadfont\hss
                                     ##\vrule height 3ex depth 1ex width 0pt\cr
                                     #2\crcr}}$}
                     \vskip 2.5cm}
\def\chapterstartform{}
\def\chead#1#2{\numberbychapter\nochapterfalse
                      \ifautonumber 
                        \global\advance\chnum by 1
                        \global\shnum=0
                        \global\sshnum=0
                        \global\ssshnum=0
                        \newtag{#1}{\chtagrefformat}
                        \updatespecialnumbers{1}
                        \edef\t@agtext{\chtagreplaceformat}
                     \else
                        \edef\t@agtext{#1}
                     \fi
                     \chaptername={#2} % for term write only ... includes \cr
                     \writeterm{<\t@agtext}{ }{\the\chaptername>}
                     \chaptername={\def\cr{ }#2}
                     \chapterstartform % here so both the number and title set
                     \titlepagestyle
                     \cheadformat{\t@agtext}{#2} % format of chead
                     \writelistfile{toc}{\chtocout}{\t@agtext}{#2}
                      }

% ========== Toc Out Forms ===========
% actually set in inrsdef.tex

%\def\shtocout{\string\shtoc}
%\def\sshtocout{\string\sshtoc}
%\def\ssshtocout{\string\ssshtoc}
%\def\dssshtocout{\string\dssshtoc}
%\def\chtocout{\string\chtoc}