Custom editing of subsection titles with hyperlinks in the table of contents

Question

I redefined subsection titles, so the table of contents looks like this:

\documentclass[twoside, a4paper, 12pt, showtrims]{book}
%\usepackage{showframe}
\usepackage[X2,T1,T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}
\usepackage{xcolor}
\usepackage[shortlabels]{enumitem}
\usepackage{etoolbox}
\usepackage[pagestyles, newparttoc, explicit]{titlesec}
\usepackage{titletoc}
\usepackage{caption}
\usepackage[linktoc = all]{hyperref}
\usepackage{cleveref}
\usepackage{hypcap}
\usepackage{lipsum}
\renewcommand\thepart{\Roman{part}}
\renewcommand\thesection{\S\arabic{section}.}
\renewcommand\thesubsection{\Roman{subsection}.}
\renewcommand\thesubsubsection{\arabic{subsubsection}.}
\makeatletter
\renewcommand\subsection{
    @startsection{subsection}{2}{\z@}%
    {-3.25ex@plus -1ex @minus -.2ex}%
    {1.5ex @plus .2ex}%
    {\normalfont\large\bfseries}
    %{style}*[toctitle]{title}
    %What should be here?
}
\makeatother
\titlecontents*{subsection}
[32 pt]
{\small}
{\thecontentslabel\ }
{}
{\ (\thecontentspage)}
[.\ ]
[]
\begin{document}
\part{The Part}
\chapter{Caption}
    \section{Com Primo}
    \lipsum[1]
    \section{Secondo}
        \subsection{Erste}
            \subsubsection{SubSub}
            This is a test.
        \subsection{Subsection 2}
    \section{Zweite}
        \subsection{Sub 1}
            \subsubsection{SubSub 2}
        \subsection{Sub Secondo}
    \part{The second Part}
    \setcounter{tocdepth}{2}
    \tableofcontents{}
\end{document}

However, such redefinition breaks hyperlinks pointing subsections. Besides I want parentheses around pages where subsections are also be hyperlinked. After many hours of searching I have been founded the best way to fix it is to renew \section command directly (as it is implemented in book.cls).

I figured out (see here) that \@startsection command (it is implemented in latex.ltx) has six required arguments. Moreover, it has two extra arguments defining toctitle and title but the are not used. So I tried to use them and define them manually. But there is a problem --- I want to use subsection title but I don't know how to access it. Answers founded here don't work (I think because of titlesec).

So, how should I redefine this command? Or are there any other ideas how to do what I want?

EDIT 1: toc and aux files:

toc

\babel@toc {english}{}\relax 
\contentsline {part}{I\hspace {1em}The Part}{1}{part.1}%
\contentsline {chapter}{\numberline {1}Caption}{3}{chapter.1}%
\contentsline {section}{\numberline {\S 1.}Com Primo}{3}{section.1.1}%
\contentsline {section}{\numberline {\S 2.}Secondo}{3}{section.1.2}%
\contentsline {subsection}{\numberline {I.}Erste}{3}{subsection.1.2.1}%
\contentsline {subsubsection}{SubSub}{3}{subsubsection*.1}%
\contentsline {subsection}{\numberline {II.}Subsection 2}{4}{subsection.1.2.2}%
\contentsline {section}{\numberline {\S 3.}Zweite}{4}{section.1.3}%
\contentsline {subsection}{\numberline {I.}Sub 1}{4}{subsection.1.3.1}%
\contentsline {subsubsection}{SubSub 2}{4}{subsubsection*.2}%
\contentsline {subsection}{\numberline {II.}Sub Secondo}{4}{subsection.1.3.2}%
\contentsline {part}{II\hspace {1em}The second Part}{5}{part.2}%
\contentsfinish

aux

\relax 
\providecommand\babel@aux[2]{}
\@nameuse{bbl@beforestart}
\providecommand\hyper@newdestlabel[2]{}
\providecommand\HyperFirstAtBeginDocument{\AtBeginDocument}
\HyperFirstAtBeginDocument{\ifx\hyper@anchor\@undefined
\global\let\oldnewlabel\newlabel
\gdef\newlabel#1#2{\newlabelxx{#1}#2}
\gdef\newlabelxx#1#2#3#4#5#6{\oldnewlabel{#1}{{#2}{#3}}}
\AtEndDocument{\ifx\hyper@anchor\@undefined
\let\newlabel\oldnewlabel
\fi}
\fi}
\global\let\hyper@last\relax 
\gdef\HyperFirstAtBeginDocument#1{#1}
\providecommand\HyField@AuxAddToFields[1]{}
\providecommand\HyField@AuxAddToCoFields[2]{}
\babel@aux{english}{}
\@writefile{toc}{\contentsline {part}{I\hspace  {1em}The Part}{1}{part.1}\protected@file@percent }
\@writefile{toc}{\contentsline {chapter}{\numberline {1}Caption}{3}{chapter.1}\protected@file@percent }
\@writefile{lof}{\addvspace {10\p@ }}
\@writefile{lot}{\addvspace {10\p@ }}
\@writefile{toc}{\contentsline {section}{\numberline {\S  1.}Com Primo}{3}{section.1.1}\protected@file@percent }
\@writefile{toc}{\contentsline {section}{\numberline {\S  2.}Secondo}{3}{section.1.2}\protected@file@percent }
\@writefile{toc}{\contentsline {subsection}{\numberline {I.}Erste}{3}{subsection.1.2.1}\protected@file@percent }
\@writefile{toc}{\contentsline {subsubsection}{SubSub}{3}{subsubsection*.1}\protected@file@percent }
\@writefile{toc}{\contentsline {subsection}{\numberline {II.}Subsection 2}{4}{subsection.1.2.2}\protected@file@percent }
\@writefile{toc}{\contentsline {section}{\numberline {\S  3.}Zweite}{4}{section.1.3}\protected@file@percent }
\@writefile{toc}{\contentsline {subsection}{\numberline {I.}Sub 1}{4}{subsection.1.3.1}\protected@file@percent }
\@writefile{toc}{\contentsline {subsubsection}{SubSub 2}{4}{subsubsection*.2}\protected@file@percent }
\@writefile{toc}{\contentsline {subsection}{\numberline {II.}Sub Secondo}{4}{subsection.1.3.2}\protected@file@percent }
\@writefile{toc}{\contentsline {part}{II\hspace  {1em}The second Part}{5}{part.2}\protected@file@percent }
\ttl@finishall
\gdef \@abspage@last{7}

The first step is too look at the aux and/or toc files and see what hyperref is actually doing. The formatting is done by \l@subsection using the arguments passed. — John Kormylo, Jul 23 '23 at 14:30
@John Kormylo, I looked through toc and aux files but I didn't find any unusual there. I can attach these files to the post. — Anton Dmitrievich, Jul 23 '23 at 15:35

Anton Dmitrievich · Accepted Answer · 2023-07-24T19:04:45.387

There is a solution (it was found here, thank Gonzalo Medina very much):

\documentclass[twoside, a4paper, 12pt, showtrims]{book}
%\usepackage{showframe}
\usepackage[X2,T1,T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}
\usepackage{xcolor}
\usepackage[shortlabels]{enumitem}
\usepackage{etoolbox}
\usepackage[pagestyles, newparttoc, explicit]{titlesec}
\usepackage{titletoc}
\usepackage{caption}
\usepackage[linktoc = all]{hyperref}
\usepackage{cleveref}
\usepackage{hypcap}
\usepackage{lipsum}
\renewcommand\thepart{\Roman{part}}
\renewcommand\thesection{\S\arabic{section}.}
\renewcommand\thesubsection{\Roman{subsection}.}
\renewcommand\thesubsubsection{\arabic{subsubsection}.}
\makeatletter
\newlength\rightmargintoc
\setlength\rightmargintoc{\linewidth}
\addtolength\rightmargintoc{0em}
\makeatletter
\def\subsectocline#1#2#3#4#5{%
    \parshape 2 #2 \rightmargintoc \dimexpr\parindent+3em\relax \rightmargintoc
    @tempdima #3
    \ifdim\lastskip=#2\relax\else\fi{{#4}~\hyperlink{\Hy@tocdestname}{(#5)}.}\hskip1em%
}
\renewcommand*\l@subsection{\subsectocline{2}{3em}{3em}}
\makeatother
\pretocmd{\part}{\addtocontents{toc}{\par}}{}{}
\pretocmd{\chapter}{\addtocontents{toc}{\par}}{}{}
\pretocmd{\section}{\addtocontents{toc}{\par}}{}{}
\AtEndDocument{%
    \ifnum\value{subsection}>0\relax
    \addtocontents{toc}{\par}
    \fi}
\begin{document}
    \part{The Part}
    \chapter{Caption}
    \section{Com Primo}
    \lipsum[1]
    \section{Secondo}
    \subsection{Erste}
    \subsubsection{SubSub}
    This is a test.
    \subsection{Subsection 2}
    \section{Zweite}
    \subsection{Sub 1}
    \subsubsection{SubSub 2}
    \subsection{Sub Secondo}
    \part{The second Part}
    \setcounter{tocdepth}{2}
    \tableofcontents{}
\end{document}

Custom editing of subsection titles with hyperlinks in the table of contents

1 Answers1