%D \module
%D   [       file=chem-ini,
%D        version=2009.05.13,
%D       subtitle=Chemistry,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

%D This module in incomplete and experimental. Eventually this code
%D will replace \PPCHTEX.

\writestatus{loading}{ConTeXt Chemistry Macros / Structure}

\registerctxluafile{chem-str}{1.001}

% We have a slightly different interface. This is unchanged:
%
% \startchemical[axis=on]
%     \chemical[SIX,ROT2,B,R6,SUB1,FIVE,ROT1,B][1]
% \stopchemical
%
% Here we use chemicalformula instead, so no longer a mix:
%
% \startchemicalformula
%     \chemical{H_2}{top}{bottom}
%     \chemical{PLUS}{top}{bottom}
%     \chemical{O}{top}{bottom}
%     \chemical{GIVES}{top}{bottom}
%     \chemical{H_2O}{top}{bottom}
% \stopchemicalformula
%
% \startchemicalformula
%     \chemical{H_2}
%     \chemical{PLUS}
%     \chemical{O}
%     \chemical{GIVES}
%     \chemical{H_2O}
% \stopchemicalformula
%
% The inline variant has only one argument:
%
% \chemical{H_2,PLUS,O,GIVES,H_2O}

% todo: seven | eight | frontsix | fontfive | carbon | newmans | chair

\unprotect

\installcorenamespace{chemical}
\installcorenamespace{chemicalsymbol}
\installcorenamespace{chemicalframed}
\installcorenamespace{chemicalsize}

\installsimplecommandhandler \??chemical {chemical} \??chemical % no \define...

\let\setupchemicals\setupchemical

\unexpanded\def\setupchemicalframed
  {\dosingleempty\dosetupchemicalframed}

\def\dosetupchemicalframed
  {\getparameters[\??chemicalframed]}

\unexpanded\def\definechemical % is global (so we don't use the commandhandler)
  {\dosingleargument\chem_define}

\def\chem_define[#1]#2%
  {\startnointerference
   \edef\currentdefinedchemical{#1}%
   \let\chemical\chem_chemical_nested
   \ctxlua{chemicals.undefine("#1")}%
   #2% flush
   \stopnointerference}

\unexpanded\def\chem_chemical_nested
  {\dodoubleempty\chem_chemical_nested_indeed}

\def\chem_chemical_nested_indeed[#1][#2]%
  {\ctxlua{chemicals.define("\currentdefinedchemical",\!!bs#1\!!es,\!!bs\detokenize{#2}\!!es)}}

% chemical symbols

\unexpanded\def\definechemicalsymbol
  {\dodoubleempty\chem_symbol_define}

\def\chem_symbol_define[#1][#2]%
  {\setvalue{\??chemicalsymbol#1}{#2}}

\unexpanded\def\chemicalsymbol[#1]%
  {\csname\??chemicalsymbol\ifcsname\??chemicalsymbol#1\endcsname\s!unknown\else#1\fi\endcsname}

\definechemicalsymbol[\s!unknown][] % empty

% size (small medium big)

\edef\chemicaltoplocation{t}
\edef\chemicalbotlocation{b}

% \unexpanded\def\chemicaltext#1% in ppchtex we had a more clever alignment
%   {\usechemicalstyleandcolor\c!style\c!color
%    \strut
%    #1} % maybe also \setstrut

\unexpanded\def\chemicaltext#1%
  {\mathematics
     {\usechemicalstyleandcolor\c!style\c!color
      \strut
      \ifcase\currentxfontsize\or\scriptstyle\or\scriptscriptstyle\fi
      #1}}

\setvalue{\??chemicalsize\v!small }{\txx}
\setvalue{\??chemicalsize\v!medium}{\tx}
\setvalue{\??chemicalsize\v!big   }{}

\newtoks       \everychemical
\newtoks       \everystructurechemical
\newconditional\indisplaychemical

\newtoks       \t_chem_every_box
\newbox        \b_chem_result
\newconditional\c_chem_some_text
\newdimen      \d_chem_width
\newdimen      \d_chem_height
\newdimen      \d_chem_depth

\unexpanded\def\startchemical
  {\dodoubleempty\chem_start}

\def\chem_start[#1][#2]%
  {\ifmmode\vcenter\else\vbox\fi
   \bgroup
   \dontcomplain
   \settrue\indisplaychemical
   \forgetall
   \ifsecondargument
     \doifassignmentelse{#1}
       {\setupcurrentchemical[#1]}% same as \currentchemical
       {\edef\currentchemical{#1}%
        \setupcurrentchemical[#2]}%
   \else\iffirstargument
     \doifassignmentelse{#1}
       {\setupcurrentchemical[#1]}% same as \currentchemical
       {\edef\currentchemical{#1}}%
   \fi\fi
   \the\everystructurechemical
   \setbox\b_chem_result\hbox\bgroup
   \ctxlua{chemicals.start {
     width  = "\chemicalparameter\c!width",
     height = "\chemicalparameter\c!height",
     left   =  \chemicalparameter\c!left,
     right  =  \chemicalparameter\c!right,
     top    =  \chemicalparameter\c!top,
     bottom =  \chemicalparameter\c!bottom,
     scale  = "\chemicalparameter\c!scale",
     axis   = "\chemicalparameter\c!axis",
     offset = "\the\dimexpr.25em\relax",
   } }%
   \startnointerference}

\unexpanded\def\stopchemical
  {\stopnointerference
   \ctxlua{chemicals.stop()}%
   \egroup
   \d_chem_width \wd\b_chem_result
   \d_chem_height\ht\b_chem_result
   \d_chem_depth \dp\b_chem_result
   \the\t_chem_every_box
   \doifelsenothing{\chemicalparameter\c!frame}\chem_framed_nop\chem_framed_yes
   \egroup}

\def\chem_framed_yes
  {\localframed%
     [\??chemicalframed]%
     [\c!frame=\chemicalparameter\c!frame,\c!align=\v!normal,\c!strut=\v!no]{\vbox{\box\b_chem_result\vss}}} % remove depth

\def\chem_framed_nop
  {\localframed%
     [\??chemicalframed]%
     [\c!align=\v!normal,\c!strut=\v!no]{\vbox{\box\b_chem_result\vss}}} % remove depth

\let\startstructurechemical\startchemical
\let\stopstructurechemical \stopchemical

\unexpanded\def\structurechemical
  {\dotripleempty\strc_chem_indeed}

\appendtoks
    \let\chemical\structurechemical
\to\everystructurechemical

\def\strc_chem_indeed
  {\ifthirdargument
     \expandafter\strc_chem_indeed_three
   \else
     \expandafter\strc_chem_indeed_two
   \fi}

\def\strc_chem_indeed_three[#1][#2][#3]%
  {\writestatus\m!chemicals{hyperlinked chemicals not yet supported}% todo reference, for the moment ignored
   \ctxlua{chemicals.component(\!!bs#2\!!es, \!!bs\detokenize{#3}\!!es, { % maybe also pass first two args this way
     rulethickness = "\the\dimexpr\chemicalparameter\c!rulethickness\relax", % todo: scaled points
     rulecolor     = "\MPcolor{\chemicalparameter\c!rulecolor}" % we can precalculate this for speedup
    } ) }%
   \ignorespaces}

\def\strc_chem_indeed_two[#1][#2]%
  {\ctxlua{chemicals.component(\!!bs#1\!!es,\!!bs\detokenize{#2}\!!es, { % maybe also pass first two args this way
     rulethickness = "\the\dimexpr\chemicalparameter\c!rulethickness\relax", % todo: scaled points
     rulecolor     = "\MPcolor{\chemicalparameter\c!rulecolor}" % we can precalculate this for speedup
    } ) }%
   \ignorespaces}

\appendtoks
    \setbox\b_chem_result\hbox{\raise\MPlly\box\b_chem_result}%
    \d_chem_width \wd\b_chem_result
    \d_chem_height\ht\b_chem_result
    \d_chem_depth \dp\b_chem_result
\to \t_chem_every_box

% kind of compatible, but text sizes instead of math sizes (i.e. tx is larger than scriptsize)

\appendtoks
   \edef\chemicalbodyfont{\chemicalparameter\c!bodyfont}% public?
   \ifx\chemicalbodyfont\empty
     \switchtobodyfont[\chemicalbodyfont]%
   \fi
   \getvalue{\??chemicalsize\chemicalparameter\c!size}%
% \to \everystructurechemical
\to \everychemical

\def\chemicaltoptext#1{\global\settrue\c_chem_some_text\gdef\m_chem_top_text{#1}\ignorespaces}
\def\chemicalbottext#1{\global\settrue\c_chem_some_text\gdef\m_chem_bot_text{#1}\ignorespaces}
\def\chemicalmidtext#1{\global\settrue\c_chem_some_text\gdef\m_chem_mid_text{#1}\ignorespaces}

\appendtoks
    \let\toptext\chemicaltoptext \glet\m_chem_top_text\empty
    \let\bottext\chemicalbottext \glet\m_chem_bot_text\empty
    \let\midtext\chemicalmidtext \glet\m_chem_mid_text\empty
    \global\setfalse\c_chem_some_text
\to \everystructurechemical

\def\doaddchemicaltexts
  {\setbox2\hbox to \d_chem_width{\strut\hss\hbox{\strut\m_chem_mid_text}\hss}%
   \setbox4\hbox to \d_chem_width{\strut\hss\hbox{\strut\m_chem_top_text}\hss}%
   \setbox6\hbox to \d_chem_width{\strut\hss\hbox{\strut\m_chem_bot_text}\hss}%
   \setbox\b_chem_result\hbox \bgroup
     \box\b_chem_result
     \hskip-\d_chem_width
     \raise\d_chem_height\hbox{\lower\ht4\box4}%
     \hskip-\d_chem_width
     \lower.5\dimexpr\ht2-\dp2\relax\box2%
     \hskip-\d_chem_width
     \lower\d_chem_depth \hbox{\raise\dp6\box6}%
     \hss
   \egroup} % text on top of chemicals

\appendtoks
    \ifconditional\c_chem_some_text
      \doaddchemicaltexts
      \d_chem_width \wd\b_chem_result
      \d_chem_height\ht\b_chem_result
      \d_chem_depth \dp\b_chem_result
    \fi
\to \t_chem_every_box

% todo: enspace or emspace

\definechemicalsymbol[space]       [\enspace\quad\enspace]
\definechemicalsymbol[plus]        [\enspace+\enspace]
\definechemicalsymbol[minus]       [\enspace-\enspace]
\definechemicalsymbol[gives]       [\chem_arrow_construct\xrightarrow]
\definechemicalsymbol[equilibrium] [\chem_arrow_construct\xrightoverleftarrow]
\definechemicalsymbol[mesomeric]   [\chem_arrow_construct\xleftrightarrow]
\definechemicalsymbol[opencomplex] [\mathematics{\Bigg[}] % not yet ok
\definechemicalsymbol[closecomplex][\mathematics{\Bigg]}] % not yet ok

\definechemicalsymbol[SPACE]       [{\chemicalsymbol[space]}]
\definechemicalsymbol[PLUS]        [{\chemicalsymbol[plus]}]
\definechemicalsymbol[MINUS]       [{\chemicalsymbol[minus]}]
\definechemicalsymbol[GIVES]       [{\chemicalsymbol[gives]}]
\definechemicalsymbol[EQUILIBRIUM] [{\chemicalsymbol[equilibrium]}]
\definechemicalsymbol[MESOMERIC]   [{\chemicalsymbol[mesomeric]}]
\definechemicalsymbol[OPENCOMPLEX] [{\chemicalsymbol[opencomplex]}]
\definechemicalsymbol[CLOSECOMPLEX][{\chemicalsymbol[closecomplex]}]

\def\chem_arrow_construct#1#2#3%
  {\enspace
   \mathematics{#1%
     {\strut\hbox \!!spread 2\emwidth{\hss\ctxlua{chemicals.inline(\!!bs#2\!!es)}\hss}}%  {\strut\hbox \!!spread 2em{\hss#2\hss}}%
     {\strut\hbox \!!spread 2\emwidth{\hss\ctxlua{chemicals.inline(\!!bs#3\!!es)}\hss}}}% {\strut\hbox \!!spread 2em{\hss#3\hss}}}%
   \enspace}

% special macros (probably needs some more work)

\def\chem_top_construct#1#2#3#4%
  {\begingroup
   \setbox0\hbox{\tx\setstrut\strut#3}%
   \setbox2\hbox{\setstrut\strut\molecule{#4}}%
   \setbox0\hbox{\raise\dimexpr\dp0+\ht2\relax\hbox to \wd2{#1\box0#2}}%
   % no: \smashbox0
   \hbox{\box0\box2}%
   \endgroup}%

\def\chem_bottom_construct#1#2#3#4%
  {\begingroup
   \setbox0\hbox{\tx\setstrut\strut#3}%
   \setbox2\hbox{\setstrut\strut#4}%
   \setbox0\hbox{\lower\dimexpr\dp2+\ht0\relax\hbox to \wd2{#1\box0#2}}%
   % no: \smashbox0
   \hbox{\box0\box2}%
   \endgroup}%

\unexpanded\def\chemicalleft#1#2%
  {\begingroup
   \hbox{\llap{\tx\setstrut\strut#1}\setstrut\strut#2}%
   \endgroup}%

\unexpanded\def\chemicalright#1#2%
  {\begingroup
   \hbox{\setstrut\strut#2\rlap{\tx\setstrut\strut#1}}%
   \endgroup}%

\unexpanded\def\chemicaltop            {\chem_top_construct    \hss   \hss  }
\unexpanded\def\chemicallefttop        {\chem_top_construct    \relax \hss  }
\unexpanded\def\chemicalrighttop       {\chem_top_construct    \hss   \relax}
\unexpanded\def\chemicalbottom         {\chem_bottom_construct \hss   \hss  }
\unexpanded\def\chemicalleftbottom     {\chem_bottom_construct \relax \hss  }
\unexpanded\def\chemicalrightbottom    {\chem_bottom_construct \hss   \relax}

\unexpanded\def\chemicaltopleft      #1{\chemicalleft {\chemicalrighttop   {#1}{}}}
\unexpanded\def\chemicalbottomleft   #1{\chemicalleft {\chemicalrightbottom{#1}{}}}
\unexpanded\def\chemicaltopright     #1{\chemicalright{\chemicallefttop    {#1}{}}}
\unexpanded\def\chemicalbottomright  #1{\chemicalright{\chemicalleftbottom {#1}{}}}

% \unexpanded\def\chemicalcentered     #1{\hbox to \fontcharwd\font`C{\setstrut\strut\hss#1\hss}}
% \unexpanded\def\chemicalleftcentered #1{\hbox to \fontcharwd\font`C{\setstrut\strut    #1\hss}}
% \unexpanded\def\chemicalrightcentered#1{\hbox to \fontcharwd\font`C{\setstrut\strut\hss#1}}

% \let\chemicalsmashedmiddle\chemicalcentered
% \let\chemicalsmashedleft  \chemicalleftcentered
% \let\chemicalsmashedright \chemicalrightcentered

\unexpanded\def\chemicalalignedtext#1#2#3%
  {\dontleavehmode
   \begingroup
   \usechemicalstyleandcolor\c!style\c!color
   \hbox to \fontcharwd\font`C{\setstrut\strut#1\molecule{#3}#2}%
   \endgroup}

\unexpanded\def\chemicalcentered     {\chemicalalignedtext\hss  \hss  }
\unexpanded\def\chemicalleftcentered {\chemicalalignedtext\relax\hss  }
\unexpanded\def\chemicalrightcentered{\chemicalalignedtext\hss  \relax}

\let\chemicalsmashedmiddle\chemicalcentered
\let\chemicalsmashedleft  \chemicalleftcentered
\let\chemicalsmashedright \chemicalrightcentered

\unexpanded\def\chemicaloxidation#1#2#3%
  {\chemicaltop{\txx\ifcase#2\relax0\else#1\convertnumber{I}{#2}\fi}{#3}}

\unexpanded\def\chemicaloxidationplus {\dotriplegroupempty\chemicaloxidation{\textplus }} % {} needed!
\unexpanded\def\chemicaloxidationminus{\dotriplegroupempty\chemicaloxidation{\textminus}} % {} needed!
\unexpanded\def\chemicalforeveropen   {\dotriplegroupempty\chemicalleft     {$\big[$}}    % {} needed!
\unexpanded\def\chemicalforeverclose  {\dotriplegroupempty\chemicalright    {$\big]$}}    % {} needed!
\unexpanded\def\chemicaloxidationone  {\chemicaloxidation\relax1}
\unexpanded\def\chemicaloxidationtwo  {\chemicaloxidation\relax2}
\unexpanded\def\chemicaloxidationthree{\chemicaloxidation\relax3}
\unexpanded\def\chemicaloxidationfour {\chemicaloxidation\relax4}
\unexpanded\def\chemicaloxidationfive {\chemicaloxidation\relax5}
\unexpanded\def\chemicaloxidationsix  {\chemicaloxidation\relax6}
\unexpanded\def\chemicaloxidationseven{\chemicaloxidation\relax7}

\appendtoks
   \let \+\chemicaloxidationplus
   \let \-\chemicaloxidationminus
   \let \[\chemicalforeveropen
   \let \]\chemicalforeverclose
   \let \1\chemicaloxidationone
   \let \2\chemicaloxidationtwo
   \let \3\chemicaloxidationthree
   \let \4\chemicaloxidationfour
   \let \5\chemicaloxidationfive
   \let \6\chemicaloxidationsix
   \let \7\chemicaloxidationseven
   \let \X\chemicaltighttext
   \let \T\chemicaltop
   \let \B\chemicalbottom
   \let \L\chemicalleft
   \let\LC\chemicalleftcentered
   \let \R\chemicalright
   \let\RC\chemicalrightcentered
   \let\TL\chemicaltopleft
   \let\BL\chemicalbottomleft
   \let\TR\chemicaltopright
   \let\BR\chemicalbottomright
   \let\LT\chemicallefttop
   \let\LB\chemicalleftbottom
   \let\RT\chemicalrighttop
   \let\RB\chemicalrightbottom
   \let\SL\chemicalsmashedleft
   \let\SM\chemicalsmashedmiddle
   \let\SR\chemicalsmashedright
\to \everychemical

\appendtoks
    \the\everychemical
\to \everystructurechemical

% inline

\unexpanded\def\chemical
  {\ifinformula
     \expandafter\displaychemical
   \else
     \expandafter\inlinechemical
   \fi}

\unexpanded\def\displaychemical
  {\dotriplegroupempty\chem_display}

\def\chem_display#1#2#3% todo:
  {\the\everychemical \everychemical\emptytoks
   \quad
   \vcenter\bgroup
     \usechemicalstyleandcolor\c!style\c!color
     \ifthirdargument
       \ifsecondargument
         \halign{&\hss##\hss\cr#2\cr\molecule{#1}\cr#3\cr}%
       \else
         \halign{&\hss##\hss\cr\molecule{#1}\cr#2\cr}%
       \fi
     \else
       \hbox{\molecule{#1}}%
     \fi
   \egroup
   \quad}

\unexpanded\def\inlinechemical#1%
  {\dontleavehmode
   \hbox{\usechemicalstyleandcolor\c!style\c!color\ctxlua{chemicals.inline(\!!bs#1\!!es)}}}

\unexpanded\def\chemicalbondrule
  {\hbox{\vrule\!!height.75ex\!!depth-\dimexpr.75ex-\linewidth\relax\!!width1em\relax}}

\definechemicalsymbol[i:space]       [\enspace\quad\enspace]
\definechemicalsymbol[i:plus]        [\enspace\mathematics{+}\enspace]
\definechemicalsymbol[i:minus]       [\enspace\mathematics{-}\enspace]
\definechemicalsymbol[i:gives]       [\enspace\mathematics{\xrightarrow{}{}}\enspace]
\definechemicalsymbol[i:equilibrium] [\enspace\mathematics{\xrightpverleftarrow{}{}}\enspace]
\definechemicalsymbol[i:mesomeric]   [\enspace\mathematics{\xleftrightarrow{}{}}\enspace]
\definechemicalsymbol[i:single]      [\chemicalbondrule]
\definechemicalsymbol[i:tripple]     [\hbox{\lower.5ex\chemicalbondrule\hskip-1em\raise.5ex\chemicalbondrule}]
\definechemicalsymbol[i:double]      [\hbox{\chemicalbondrule\hskip-1em\lower.5ex\chemicalbondrule\hskip-1em\raise.5ex\chemicalbondrule}]

\unexpanded\def\chemicalsinglebond {\chemicalsymbol[i:single]}
\unexpanded\def\chemicaldoublebond {\chemicalsymbol[i:tripple]}
\unexpanded\def\chemicaltriplebond {\chemicalsymbol[i:double]}
\unexpanded\def\chemicalgives      {\chemicalsymbol[i:gives]}
\unexpanded\def\chemicalmesomeric  {\chemicalsymbol[i:mesomeric]}
\unexpanded\def\chemicalequilibrium{\chemicalsymbol[i:equilibrium]}
\unexpanded\def\chemicalsplus      {\chemicalsymbol[i:plus]}
\unexpanded\def\chemicalsminus     {\chemicalsymbol[i:minus]}
\unexpanded\def\chemicalsspace     {\chemicalsymbol[i:space]}
\unexpanded\def\chemicalinline   #1{#1}

% display

\newconditional\c_chem_has_top
\newconditional\c_chem_has_bot

\newtoks\t_chem_top
\newtoks\t_chem_mid
\newtoks\t_chem_bot

\newif\ifinchemicalformula

\unexpanded\def\startchemicalformula
  {\mathortext\vcenter\vbox\bgroup
   \forgetall
   \inchemicalformulatrue
   \the\everychemical
   \everychemical\emptytoks
   \t_chem_top\emptytoks % not needed
   \t_chem_mid\emptytoks % not needed
   \t_chem_bot\emptytoks % not needed
   \let\chemical\formulachemical
   \setfalse\c_chem_has_top
   \setfalse\c_chem_has_bot}

\unexpanded\def\stopchemicalformula
  {\tabskip1em\relax
   \nointerlineskip
   \ifconditional\c_chem_has_top
     \ifconditional\c_chem_has_bot
       \halign{&\hss\usechemicalstyleandcolor\c!style\c!color##\hss\cr\the\t_chem_top\cr\the\t_chem_mid\cr\the\t_chem_bot\cr}%
     \else
       \halign{&\hss\usechemicalstyleandcolor\c!style\c!color##\hss\cr\the\t_chem_top\cr\the\t_chem_mid\cr}%
     \fi
   \else
     \ifconditional\c_chem_has_bot
       \halign{&\hss\usechemicalstyleandcolor\c!style\c!color##\hss\cr\the\t_chem_mid\cr\the\t_chem_bot\cr}%
     \else
       \halign{&\hss\usechemicalstyleandcolor\c!style\c!color##\hss\cr\the\t_chem_mid\cr}%
     \fi
   \fi
   \egroup}

\unexpanded\def\formulachemical
  {\relax\dotriplegroupempty\chem_formula}

\def\chem_formula#1#2#3% we could do hboxes and measure
  {\ifcsname\??chemicalsymbol\detokenize{#1}\endcsname
     \t_chem_mid\expandafter{\the\t_chem_mid\chem_formula_mid{#1}{#2}{#3}}%
   \else
     \ifthirdargument
       \doifelsenothing{#2}\chem_formula_top_nop{\chem_formula_top_yes{#2}}%
       \doifelsenothing{#3}\chem_formula_bot_nop{\chem_formula_bot_yes{#3}}%
     \else\ifsecondargument
       \chem_formula_top_nop
       \doifelsenothing{#2}\chem_formula_bot_nop{\chem_formula_bot_yes{#2}}%
     \else
       \chem_formula_top_nop
       \chem_formula_bot_nop
     \fi\fi
     \t_chem_mid\expandafter{\the\t_chem_mid\molecule{#1}&}%
   \fi}

\def\chem_formula_mid#1%
  {\csname\??chemicalsymbol\detokenize{#1}\endcsname}

\def\chem_formula_top_nop  {\t_chem_top\expandafter{\the\t_chem_top&}}
\def\chem_formula_bot_nop  {\t_chem_bot\expandafter{\the\t_chem_bot&}}
\def\chem_formula_top_yes#1{\t_chem_top\expandafter{\the\t_chem_top\chem_formula_top_indeed{#1}&}\settrue\c_chem_has_top}
\def\chem_formula_bot_yes#1{\t_chem_bot\expandafter{\the\t_chem_bot\chem_formula_bot_indeed{#1}&}\settrue\c_chem_has_bot}

\def\chem_formula_top_indeed#1{\strut#1}
\def\chem_formula_bot_indeed#1{\strut#1}

% gone: state option resolution offset (now frame offset) alternative

\setupchemicalframed
  [\c!align=\v!normal,
   \c!strut=\v!no,
   \c!offset=\v!overlay,
   \c!frame=off]

\setupchemical
  [\c!frame=,
   \c!width=0,
   \c!height=0,
   \c!left=0,
   \c!right=0,
   \c!top=0,
   \c!bottom=0,
   \c!bodyfont=,
   \c!scale=\v!medium,
   \c!size=\v!medium,
   \c!textsize=\v!big,
   \c!axis=\v!off,
   \c!style=\rm,
   \c!location=,
   \c!color=,
   \c!rulethickness=\linewidth,
   \c!rulecolor=,
   \c!factor=1]

\protect \endinput