%D \module
%D   [       file=x-cml,
%D        version=2007.09.03, % reimplementation
%D          title=\CONTEXT\ XML Modules,
%D       subtitle=MkIV ChemML renderer,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

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

\usemodule[pictex,chemic] % someday we will do structural fomulas in mp

%D The following code assumes a load||flush approach to \XML.

\unprotect

\startxmlsetups xml:cml:process

    \xmlstrip {\xmldocument} {cml:chem|cml:ichem|cml:dchem|cml:reaction|cml:molecule|cml:ion|cml:structure}

    \xmlgrab {\xmldocument} {cml:*}                                                  {*}
    \xmlgrab {\xmldocument} {cml:gives|cml:equilibrium|cml:mesomeric}                {cml:arrow}
    \xmlgrab {\xmldocument} {cml:plus|cml:minus|cml:equal}                           {cml:operator}
    \xmlgrab {\xmldocument} {cml:bond|cml:singlebond|cml:doublebound|cml:triplebond} {cml:bond}

    \xmlgrab {\xmldocument} {pi::chemml} {cml:pi}
\stopxmlsetups

\xmlregistersetup{xml:cml:process}

\xmlregisterns{cml}{chemml}

\unexpanded\def\setupCMLappearance[#1]{\dodoubleargument\getparameters[@@CML#1]}

\setupCMLappearance [ion] [\c!alternative=\v!a]

\startluacode
    function lxml.cml_do_pi(id)
        local str = xml.content(lxml.id(id))
        local _, class, key, value = str:match("^(%S+)%s+(%S+)%s+(%S+)%s+(%S+)%s*$")
        if key and value then
            tex.sprint(tex.ctxcatcodes,string.format("\\setupCMLappearance[%s][%s=%s]",class, key, value))
        end
    end
\stopluacode

\def\doifelseCMLvariable#1#2#3% id key value
  {\doifelse{\xmlatt{#1}{#2}}{#3}
     \firstoftwoarguments
     {\doifelse{\getvalue{@@CML\xmltag{#1}#2}}{#3}
        \firstoftwoarguments
        \secondoftwoarguments}}

\startxmlsetups cml:pi
    \ctxlua{lxml.cml_do_pi(#1)}
\stopxmlsetups

\startxmlsetups cml:chem
    \automathematics{\xmlflush{#1}}
\stopxmlsetups
\startxmlsetups cml:ichem
    \inlinemathematics{\xmlflush{#1}}
\stopxmlsetups
\startxmlsetups cml:dchem
    \displaymathematics{\xmlflush{#1}}
\stopxmlsetups

\startxmlsetups cml:reaction
    \xmlflush{#1}
\stopxmlsetups

\def\doCMLtext#1#2#3% main top bot
  {\setbox0\hbox{\doifsomething{#2}{\txx\setstrut\strut\ignorespaces#2\unskip}}%
   \setbox2\hbox{\ignorespaces\strut#1\unskip}%
   \setbox4\hbox{\doifsomething{#3}{\txx\setstrut\strut\ignorespaces#3\unskip}}%
   \scratchdimen=\wd2\advance\scratchdimen-.5em
   \ifdim\wd0>\scratchdimen
     \setbox0\hbox spread .5em{\hss\box0\hss}%
   \fi
   \ifdim\wd4>\scratchdimen
     \setbox4\hbox spread .5em{\hss\box4\hss}%
   \fi
   \setbox6=\vbox
     {\offinterlineskip\halign{\hss##\hss\cr\copy0\cr\copy2\cr\copy4\cr}}%
   \hbox{\lower\ht4\hbox{\lower\dp2\box6}}}

\def\doCMLamount#1%
  {\scratchcounter0\xmlatt{#1}{n}\relax
   \ifnum\scratchcounter>0 \number\scratchcounter \fi}

\startxmlsetups cml:molecule
    \doCMLtext
        {\doCMLamount{#1}
         \xmlall{#1}{cml:atom|cml:bond|cml:singlebond|cml:doublebond|cml:triplebond}}
        {\xmlindex{#1}{cml:caption}{2}}
        {\xmlindex{#1}{cml:caption}{1}}
\stopxmlsetups

\startxmlsetups cml:atom
    \doCMLtext {
            \lohi {
                $\tfxx\xmlatt{#1}{protons}$
            } {
                $\tfxx\xmlatt{#1}{weight}$
            }
            \xmlflush{#1}
            \lohi {
                $\tfxx\xmlatt{#1}{n}$
            } {
                $\tfxx\xmlatt{#1}{charge}$%
            }
        }
        {\xmlindex{#1}{cml:caption}{2}}
        {\xmlindex{#1}{cml:caption}{1}}
\stopxmlsetups

\startxmlsetups cml:ion
    \doifelseCMLvariable{#1}{alternative}{b} {
        \left[
        \doCMLtext
            {\doCMLamount{#1}
             \xmlall{#1}{cml:atom}}
            {\xmlindex{#1}{cml:caption}{2}}
            {\xmlindex{#1}{cml:caption}{1}}
        \right]
    } {
        \doCMLtext
            {\doCMLamount{#1}
             \xmlall{#1}{cml:atom}}
            {\xmlindex{#1}{cml:caption}{2}}
            {\xmlindex{#1}{cml:caption}{1}}
    }
    \high {\xmlatt{#1}{charge}}
\stopxmlsetups

\def\doCMLgives      {\xrightarrow}
\def\doCMLequilibrium{\xleftrightarrow}
\def\doCMLmesomeric  {\xrightoverleftarrow}
\def\doCMLplus       {+}
\def\doCMLminus      {-}
\def\doCMLequal      {=}

\startxmlsetups cml:arrow
    \quad
    \executeifdefined{doCML\xmlname{#1}}\doCMLgives{\tf\xmlindex{#1}{cml:caption}{2}}{\tf\xmlindex{#1}{cml:caption}{1}}
    \quad
\stopxmlsetups

\startxmlsetups cml:operator
    \quad
    \mathop{\executeifdefined{doCML\xmlname{#1}}\doCMLplus}
    \quad
\stopxmlsetups

\startxmlsetups cml:bond
    \executeifdefined{doCML\xmlname{#1}} {
        \ifcase0\xmlatt{#1}{n}\relax
            \doCMLsinglebond
        \or
            \doCMLdoublebond
        \or
            \doCMLtriplebond
        \fi
    }
\stopxmlsetups

\def\doCMLbond
  {\hrule\!!width\hsize\!!height.1ex\relax}

\def\dodoCMLbond#1#2#3%
  {\begingroup
   \setbox\scratchbox\hbox{$M$}%
   \vbox to \ht\scratchbox
     {\hsize\wd\scratchbox
      \vskip.1\wd\scratchbox
      #1\vfill#2\vfill#3%
      \vskip.1\wd\scratchbox}%
   \endgroup}

\def\doCMLsinglebond{\dodoCMLbond\relax    \doCMLbond\relax    }
\def\doCMLdoublebond{\dodoCMLbond\doCMLbond\relax    \doCMLbond}
\def\doCMLtriplebond{\dodoCMLbond\doCMLbond\doCMLbond\doCMLbond}

\startxmlsetups cml:structure
    \startchemical
    \xmlall{#1}{cml:component}
    \stopchemical
\stopxmlsetups

% It makes not much sense to adapt ppchtex to accept different input. Maybe some day.

\startluacode
    function lxml.cml_do_graphic(id)
        local t = { }
        for r, d, k in xml.elements(lxml.id(id),"cml:graphic") do
            t[#t+1] = xml.tostring(d[k].dt)
        end
        tex.sprint(tex.ctxcatcodes,table.concat(t,","))
    end
    function lxml.cml_no_graphic(id)
        local t = { }
        for r, d, k in xml.elements(lxml.id(id),"cml:text|cml:oxidation|cml:annotation") do
            local dk = d[k]
            if dk.tg == "oxidation" then
                t[#t+1] = string.format("\\chemicaloxidation{%s}{%s}{%s}",r.at.sign or "",r.at.n or 1,xml.tostring(dk.dt))
            elseif dk.tg == "annotation" then
                local location = r.at.location or "r"
                local caption  = xml.content(xml.first(dk,"cml:caption"))
                local text     = xml.content(xml.first(dk,"cml:text"))
                t[#t+1] = string.format("\\doCMLannotation{%s}{%s}{%s}",location,caption,text)
            else
                t[#t+1] = xml.tostring(dk.dt) or ""
            end
        end
        tex.sprint(tex.ctxcatcodes,table.concat(t,","))
    end
\stopluacode

\startxmlsetups cml:component
    \expanded {
        \chemical
            [\ctxlua{lxml.cml_do_graphic("#1")}]
            [\ctxlua{lxml.cml_no_graphic("#1")}]
    }
\stopxmlsetups

\unexpanded\def\doCMLannotation#1% #2#3% loc caption text
  {\XMLval{cml:a:l}{#1}{\chemicalright}}% {#2}{#3}}

\mapXMLvalue {cml:a:l} {t}  {\chemicaltop}
\mapXMLvalue {cml:a:l} {b}  {\chemicalbottom}
\mapXMLvalue {cml:a:l} {l}  {\chemicalleft}
\mapXMLvalue {cml:a:l} {r}  {\chemicalright}
\mapXMLvalue {cml:a:l} {lc} {\chemicalleftcentered}  % \mapXMLvalue {cml:a:l} {cl} {\chemicalleftcentered}
\mapXMLvalue {cml:a:l} {rc} {\chemicalrightcentered} % \mapXMLvalue {cml:a:l} {cr} {\chemicalrightcentered}
\mapXMLvalue {cml:a:l} {tl} {\chemicaltopleft}       % \mapXMLvalue {cml:a:l} {lt} {\chemicaltopleft}
\mapXMLvalue {cml:a:l} {bl} {\chemicalbottomleft}    % \mapXMLvalue {cml:a:l} {lb} {\chemicalbottomleft}
\mapXMLvalue {cml:a:l} {tr} {\chemicaltopright}      % \mapXMLvalue {cml:a:l} {rt} {\chemicaltopright}
\mapXMLvalue {cml:a:l} {br} {\chemicalbottomright}   % \mapXMLvalue {cml:a:l} {rb} {\chemicalbottomright}
\mapXMLvalue {cml:a:l} {lt} {\chemicallefttop}       % \mapXMLvalue {cml:a:l} {tl} {\chemicallefttop}
\mapXMLvalue {cml:a:l} {lb} {\chemicalleftbottom}    % \mapXMLvalue {cml:a:l} {bl} {\chemicalleftbottom}
\mapXMLvalue {cml:a:l} {rt} {\chemicalrighttop}      % \mapXMLvalue {cml:a:l} {tr} {\chemicalrighttop}
\mapXMLvalue {cml:a:l} {rb} {\chemicalrightbottom}   % \mapXMLvalue {cml:a:l} {br} {\chemicalrightbottom}
\mapXMLvalue {cml:a:l} {x}  {\chemicaltighttext}
\mapXMLvalue {cml:a:l} {sl} {\chemicalsmashedleft}   % \mapXMLvalue {cml:a:l} {ls} {\chemicalsmashedleft}
\mapXMLvalue {cml:a:l} {sm} {\chemicalsmashedmiddle} % \mapXMLvalue {cml:a:l} {ms} {\chemicalsmashedmiddle}
\mapXMLvalue {cml:a:l} {sr} {\chemicalsmashedright}  % \mapXMLvalue {cml:a:l} {rs} {\chemicalsmashedright}

\startxmlsetups cml:forever
    \left[\xmlflush{#1}\right]
\stopxmlsetups

% \starttext
%     \xmlprocess{main}{cmltest.xml}{xml:process}
% \stoptext

\protect \endinput