producing ODT Arabic edition with apparatus in parnotes via tex4ht: customizing parnote formatting

Question

I would like to convert my edition of Arabic text into ODT format. The edition uses notes that are supposed appear in a smaller font in a paragraph below the text (not at the bottom of each page). I would like the footnote hooks to be in Arabic-style numerals ١٢٣٤٥٦٧٨٩٠ rather than Roman-style numerals 1234567890. Ideally I would like to be able to select the font (Amiri) to which it will output (current default is Tahoma for the Arabic text).

What I haven't been able to figure out is

1. how to make the footnote hooks Arabic-style
2. how to make the notes paragraph a much smaller font size
3. how to remove a spurious space that comes after the footnote marker in the notes paragraph.

How can I do this?

MWE

myfile.tex:

\documentclass[12pt,letterpaper,oldfontcommands]{memoir}

\usepackage{fontspec}
\usepackage{xunicode}
\usepackage[T1]{fontenc}

\newcommand{%
\خ%
    }[2]{%
    \ar{#1}\footnoteA{\ar{#1%
    :
    #2}}%
    }

\newfontfamily\arabicfont[Script=Arabic,Mapping=arabicdigits]{Amiri}

%Arabic
\newcommand{\ar}[1]{#1}
\newenvironment{arab}{}{}

% APPARATUS FOR VARIANTS IN ARABIC TEXT
\usepackage[para]{manyfoot}
\SetFootnoteHook{\setRL}
\DeclareNewFootnote[para]{A}[alph]

%%%%%%%%%%%%%%%%%%%%%%%%%%
% Placing Arabic apparatus at the end of each paragraph
% (WARNING !!! :  currently only works if VARIANT commands only come within `arab` environments)
\usepackage[restart]{parnotes} % package
\renewcommand{\parnotefmt}[1]{\tiny\noindent #1}
\renewcommand{\footnoteA}[1]{\parnote{#1}} % mk app fns parnotes
% \renewcommand*{\parnotecusmarkfmt}[1]{\arabicfont\addfontfeature{Mapping=arabicdigits}\textsuperscript{#1}}
\renewcommand*{\parnotecusmarkfmt}[1]{\arabicfont\addfontfeature{Mapping=arabicdigits}\textsuperscript{#1}}

\let\origArab\arab
\renewenvironment{arab}{\begin{origArab}}{\parnotes{}\end{origArab}} % make arab environment print parnotes at the end
%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\begin{arab}
\خ{لكن لما}{ڤ؛ إنني كلما: ي}
\end{arab}
\end{document}

Compiled with

make4ht -uxm draft -f odt -c myconfig.cfg

where myconfig.cfg is:

\Preamble{xhtml}
\ConfigureOO{Footnote}{
<style:style
    style:name="Footnote"
    style:family="paragraph"
    style:parent-style-name="Standard"
    style:class="extra">\Hnewline
  <style:paragraph-properties
             fo:margin-left="0in"
             fo:margin-right="0in"
             fo:text-indent="0.1in"
              style:auto-text-indent="false"/>
  <style:text-properties fo:font-size="83.3333333333333333333333\%"
      style:font-size-asian="83.3333333333333333333333\%"
      style:font-size-complex="83.3333333333333333333333\%" />
</style:style>\Hnewline
<text:notes-configuration text:note-class="footnote"
    text:citation-style-name="Footnote_20_Symbol"
    text:citation-body-style-name="Footnote_20_anchor"
    style:num-format="1" text:start-value="0"
    text:footnotes-position="page"
    text:start-numbering-at="document" />\Hnewline
<style:style style:name="Footnote_20_Symbol"
style:display-name="Footnote Symbol" style:family="text" >\Hnewline
  <style:text-properties style:text-position="super 58\%" />\Hnewline
</style:style>
<style:style style:name="Footnote_20_anchor"
style:display-name="Footnote anchor" style:family="text">
  <style:text-properties style:text-position="super 58\%" />\Hnewline
</style:style>\Hnewline
}

\ConfigureOO{verse}{\Hnewline
<style:style style:name="verse"
             style:family="paragraph"
             style:parent-style-name="Text-body"
             style:next-style-name="Text-body">
<style:paragraph-properties  fo:margin-left="1.499cm"
             fo:margin-right="1cm"
             fo:margin-top="0cm"
             fo:margin-bottom="0cm"
             fo:text-indent="-0.499cm"
             style:auto-text-indent="false">
   <style:tab-stops/>
</style:paragraph-properties >
</style:style>
\Hnewline}

\xeuniuseblock{Greek}
\xeuniuseblock{Arabic}
\makeatletter
\ConfigureEnv{arab}{\@rltrue}{\@rlfalse}{}{}
\Configure{ref}{\Link}{\EndLink}{}
\makeatother
\begin{document}
\EndPreamble

current output

desired output

Answer 1

Your original TeX file doesn't compile correctly with XeLaTeX or LuaLaTeX. Here is a modified version that compiles with both of them:

% https://tex.stackexchange.com/q/495709/2891
\documentclass[12pt,letterpaper,oldfontcommands]{memoir}

\usepackage{fontspec}
% \usepackage{xunicode}
% \usepackage[T1]{fontenc}
\ifdefined\HCode
  \usepackage{babel}
\else
\ifdefined\directlua
\usepackage[nil,bidi=basic-r]{babel}
\babelprovide[import=ar,main]{arabic}
\babelfont[arabic]{rm}{Amiri}
\else
% \usepackage[]{babel}
\usepackage{polyglossia}
\setmainlanguage{arabic}
%\setotherlanguage{arabic}
\fi
\fi

\newcommand{%
\خ%
    }[2]{%
    \ar{#1}\footnoteA{\ar{#1%
    :
    #2}}%
    }

% \newfontfamily\arabicfont[Script=Arabic,Mapping=arabicdigits]{Amiri}
\newfontfamily\arabicfont[Script=Arabic]{Amiri}

%Arabic
\newcommand{\ar}[1]{\bgroup\arabicfont#1\egroup}
\newenvironment{arab}{}{}

% APPARATUS FOR VARIANTS IN ARABIC TEXT
\usepackage[para]{manyfoot}
\SetFootnoteHook{\setRL}
\DeclareNewFootnote[para]{A}[alph]

%%%%%%%%%%%%%%%%%%%%%%%%%%
% Placing Arabic apparatus at the end of each paragraph
% (WARNING !!! :  currently only works if VARIANT commands only come within `arab` environments)
\usepackage[restart]{parnotes} % package
\renewcommand{\parnotefmt}[1]{\tiny\noindent #1}
\renewcommand{\footnoteA}[1]{\parnote{#1}} % mk app fns parnotes
% \renewcommand*{\parnotecusmarkfmt}[1]{\arabicfont\addfontfeature{Mapping=arabicdigits}\textsuperscript{#1}}
\renewcommand*{\parnotecusmarkfmt}[1]{\arabicfont\textsuperscript{\arabicdigits{#1}}}

\let\origArab\arab
\renewenvironment{arab}{\begin{origArab}}{\parnotes{}\end{origArab}} % make arab environment print parnotes at the end
%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\begin{arab}
\خ{لكن لما}{ڤ؛ إنني كلما: ي}
\end{arab}

\end{document}

I've made few changes:

% \usepackage{xunicode}
% \usepackage[T1]{fontenc}
\ifdefined\HCode
  \usepackage{babel}
\else
\ifdefined\directlua
\usepackage[nil,bidi=basic-r]{babel}
\babelprovide[import=ar,main]{arabic}
\babelfont[arabic]{rm}{Amiri}
\else
% \usepackage[]{babel}
\usepackage{polyglossia}
\setmainlanguage{arabic}
%\setotherlanguage{arabic}
\fi
\fi

With tex4ht only babel package is required, with no language definitions, with LuaLaTeX and XeLaTeX babel or polyglossia with options for correct text directions are used.

Another change is to parnotes mark:

\renewcommand*{\parnotecusmarkfmt}[1]{\arabicfont\textsuperscript{\arabicdigits{#1}}}

The change is that it uses the \arabicdigits command instead of relying on the XeLaTeX font mapping mechanism. Thanks to this change, it works with LuaLaTeX.

The configuration file needed only a small change:

\Preamble{xhtml,ooffice}
\ConfigureOO{Footnote}{
<style:style
    style:name="Footnote"
    style:family="paragraph"
    style:parent-style-name="Standard"
    style:class="extra">\Hnewline
  <style:paragraph-properties
             fo:margin-left="0in"
             fo:margin-right="0in"
             fo:text-indent="0.1in"
              style:auto-text-indent="false"/>
  <style:text-properties fo:font-size="83.3333333333333333333333\%"
      style:font-size-asian="83.3333333333333333333333\%"
      style:font-size-complex="83.3333333333333333333333\%" />
</style:style>\Hnewline
<text:notes-configuration text:note-class="footnote"
    text:citation-style-name="Footnote_20_Symbol"
    text:citation-body-style-name="Footnote_20_anchor"
    style:num-format="1" text:start-value="0"
    text:footnotes-position="page"
    text:start-numbering-at="document" />\Hnewline
<style:style style:name="Footnote_20_Symbol"
style:display-name="Footnote Symbol" style:family="text" >\Hnewline
  <style:text-properties style:text-position="super 58\%" />\Hnewline
</style:style>
<style:style style:name="Footnote_20_anchor"
style:display-name="Footnote anchor" style:family="text">
  <style:text-properties style:text-position="super 58\%" />\Hnewline
</style:style>\Hnewline
}

\ConfigureOO{verse}{\Hnewline
<style:style style:name="verse"
             style:family="paragraph"
             style:parent-style-name="Text-body"
             style:next-style-name="Text-body">
<style:paragraph-properties  fo:margin-left="1.499cm"
             fo:margin-right="1cm"
             fo:margin-top="0cm"
             fo:margin-bottom="0cm"
             fo:text-indent="-0.499cm"
             style:auto-text-indent="false">
   <style:tab-stops/>
</style:paragraph-properties >
</style:style>
\Hnewline}

\def\loopoverdigits#1{\ifx\relax#1\else%
% Unicode block for Arabic numerals starts at U+0660
% the following special command inserts the XML entity
% for the number, which will be converted to Unicode char
% by tex4ht
\special{t4ht@+&{35}x066#1{59}}x%
\expandafter\loopoverdigits\fi}

\def\arabicdigits#1{\NoFonts\loopoverdigits#1\relax\EndNoFonts}
\ifdefined\xeuniuseblock
\xeuniuseblock{Greek}
\xeuniuseblock{Arabic}
\fi
\makeatletter
\ConfigureEnv{arab}{\@rltrue}{\@rlfalse}{}{}
\Configure{ref}{\Link}{\EndLink}{}
\makeatother
\begin{document}
\EndPreamble

I've added modified definition for \arabicdigits:

\def\loopoverdigits#1{\ifx\relax#1\else%
% Unicode block for Arabic numerals starts at U+0660
% the following special command inserts the XML entity
% for the number, which will be converted to Unicode char
% by tex4ht
\special{t4ht@+&{35}x066#1{59}}x%
\expandafter\loopoverdigits\fi}

\def\arabicdigits#1{\NoFonts\loopoverdigits#1\relax\EndNoFonts}

It loops over all digits in the argument and prints them as a Unicode entity, using the \special{t4ht@+&{35}x066#1{59}}x command. It utilizes the fact, that the Arabic numbers start at 0660 codepoint, so we can just pass the number as the last digit in the codepoint and it will end as a correct Unicode value.

Here is the result in LO: