\input ptb-pdfData
\input pdfDstruct/ptb-hyperlinks
\input pdfDstruct/ptb-tableofcontents
\_checkloaded{indexes}

\createarray{index_listing}

%\def\_addtoindex#1#2{%
%    \def\_temp{#2}%
%    \ifx\_temp\empty%
%        \expanded{\noexpand\_rappendarray{\noexpand\gotoanchor{index@anchor@\the\indexcnt}{\@defaultindexval}}}{index@#1@pages}%
%    \else%
%        \expanded{\noexpand\_rappendarray{\noexpand\gotoanchor{index@anchor@\the\indexcnt}{#2}}}{index@#1@pages}%
%    \fi%
%}

\def\_rfindarray#1#2{\findarray{#2}{#1}}
\def\_runiqueappendarray#1#2{\uniqueappendarray{#2}{#1}}

\newcount\indexcnt
%\def\_indexize#1[#2]{{%
%    \globalsetters%
%    \anchor{index@anchor@\the\indexcnt}%
%    \lowercase{\def\_temp{#1}}%
%    \_xp\_rfindarray\_xp{\_temp}{index_listing}{\_regA}%
%    \ifx\@return@value\False%
%        \_xp\_rappendarray\_xp{\_temp}{index_listing}%
%    \fi%
%    \unless\ifcsname arr@index@\_temp @pages\endcsname%
%        \createarray{index@\_temp @pages}%
%    \fi%
%    \_xp\_addtoindex\_xp{\_temp}{#2}%
%    \global\advance\indexcnt by 1\relax%
%}}
%
%\def\indexize#1{\_ifnextchar[ {\_indexize{#1}}{\_indexize{#1}[]}}

\def\_lowercasedef#1#2{%
    \lowercase{\def#1{#2}}%
}

\def\_indexize{{%
    \globalsetters%
    \anchor{index@anchor@\the\indexcnt}%
    \_xp\_runiqueappendarray\_xp{\_category}{index_listing}%
    \ensurearray{index@category@\_category}%
    \unless\ifx\_item\empty%
        \_xp\_runiqueappendarray\_xp{\_item}{index@category@\_category}%
    \fi%
    \ensurearray{index@\_category:\_item}%
    \_xp\_rappendarray\_xp{\_value}{index@\_category:\_item}%
    %\_xp\_addtoindex\_xp{\_category}{#2}%
    \global\advance\indexcnt by 1\relax%
}}

\def\indexize#1{%
    \mapkeys{%
        category={%
            name=_category,
            definition=\_lowercasedef,
            required%
        },
        item={%
            name=_item,
            definition=\_lowercasedef,
            default=%
        },
        value={%
            name=_value,
            required%
        },
        expand value,
        add hyperlink%
    }{#1}%
    \keyexists{expand value}{\_regA}\lastkeys%
    \unless\ifx\_regA\_nul%
        \edef\_value{\_value}%
    \fi%
    \keyexists{add hyperlink}{\_regA}\lastkeys%
    \unless\ifx\_regA\_nul%
        \_xp\def\_xp\_value\_xp{\_xp\unexpanded\_xp{\_value}}%
        \edef\_value{\noexpand\gotoanchor{index@anchor@\the\indexcnt}{\_value}}%
    \fi%
    \_indexize%
}

\def\_seealso{{%
    \globalsetters%
    \_xp\_runiqueappendarray\_xp{\_category}{index_listing}%
    \unless\ifx\_item\empty%
        \ensurearray{index@category@\_category}%
        \_xp\_runiqueappendarray\_xp{\_item}{index@category@\_category}%
    \fi%
    \ensurearray{index@\_category:\_item @see-also}%
    \_xp\_rappendarray\_xp{\_dest}{index@\_category:\_item @see-also}%
}}

\def\seealso#1{%
    \mapkeys{%
        category={%
            name=_category,
            definition=\_lowercasedef,
            required%
        },
        item={%
            name=_item,
            definition=\_lowercasedef,
            default=%
        },
        dest={%
            name=_dest,
            required%
        },
        hyperlink={
            name=_hlink%
        },
        index link%
    }{#1}%
    \keyexists{hyperlink}{\_regA}\lastkeys%
    \unless\ifx\_regA\_nul%
        \_xp\def\_xp\_dest\_xp{\_xp\unexpanded\_xp{\_dest}}%
        \keyexists{index link}{\_regA}\lastkeys%
        \ifx\_regA\_nul%
            \edef\_dest{\noexpand\gotoanchor{\_hlink}{\_dest}}%
        \else%
            \edef\_dest{\noexpand\gotoanchor{index@\_hlink @anchor}{\_dest}}%
        \fi%
    \fi%
    \_seealso%
}

\newif\ifsecondcol
\newbox\firstcol
\newdimen\ohsize    \ohsize=\hsize

\unless\ifcsname makeheadline\endcsname
    \def\makeheadline{}
    %\def\makefootline{\hbox to\hsize{\baselineskip=24pt \lineskiplimit=0pt\hfil\thepage\hfil}}
    \def\makefootline{}
\fi

\def\twocoloutput{%
    \ifsecondcol%
        \shipout\vbox{\makeheadline\hbox to\ohsize{\box\firstcol\hfil\box255}\hsize=\ohsize\makefootline}%
        \global\secondcolfalse%
    \else%
        \global\setbox\firstcol=\vbox{\box255}%
        \global\secondcoltrue%
    \fi%
    \unless\ifnum\outputpenalty>-\@MM
        \ifsecondcol \null\eject\fi
    \fi%
}

\def\_titlecase#1{\uppercase{#1}}
\def\titlecase#1{\_titlecase#1}

% #1: category #2: type
\def\print_index_type#1#2#3{%
    \par\quitvmode%
    {%
        \advance\leftskip by .5cm\relax
        \kern-.5cm\titlecase{#2}\anchor{index@#1:#2@anchor}: 
        \ifcsname arr@index@#1:#2\endcsname
            \quitvmode\printarray{index@#1:#2}\par
        \fi%
        \ifcsname arr@index@#1:#2@see-also\endcsname%
            {\advance\leftskip by .25cm\relax
            \quitvmode\kern-.25cm\relax See also: \printarray{index@#1:#2@see-also}\par}%
        \fi%
    }%
}

% #1: category
\def\print_index_category#1#2{%
    \par\quitvmode{%
        \advance\leftskip by .5cm\relax
        \kern-.5cm\titlecase{#1}\anchor{index@#1:@anchor}: 
        \ifcsname arr@index@#1:\endcsname%
            \printarray{index@#1:}\par%
        \fi%
        \ifcsname arr@index@category@#1\endcsname%
            \sortarr{index@category@#1}{index@category@#1}\_cmp_str%
            \arraymap{index@category@#1}{\print_index_type{#1}}\par%
        \fi%
        \ifcsname arr@index@#1:@see-also\endcsname%
            \par{\advance\leftskip .25cm\relax
            \quitvmode\kern-.25cm See also: \printarray{index@#1:@see-also}\par}%
        \fi%
    }%
}

\def\index{%
    {%\hsize=0.4\hsize%
    \parindent=\z@%
    %\output={\twocoloutput}%
    \section{Index}%
    \sortarr{index_listing}{index_listing}\_cmp_str%
    \arraymap{index_listing}\print_index_category%
    \par\vfill\penalty-\@MM\eject}%
}

\def\@defaultindexval{\the\pageno}
\def\_addtoindex#1[#2]{\indexize{category=#1, item=#2, value=\@defaultindexval, expand value, add hyperlink}}
\def\addtoindex#1{\_ifnextchar[ {\_addtoindex{#1}}{\_addtoindex{#1}[]}}