%D \module
%D   [       file=math-acc,
%D        version=2013.07.31,
%D          title=\CONTEXT\ Math Macros,
%D       subtitle=Accents,
%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.

\writestatus{loading}{ConTeXt Math Macros / Accents}

% There are probably errors ... too distracted by amazing (piano) music videos running
% on top of scite ... so: experimental code.

\unprotect

% This module permits overloading of accents so that we can do fancy things. The
% implementation is similar to stackers. By default accenst are defined in a simple
% way. Contrary to extensibles accents cannot grow indefinitely. Alas the
% implementation of accents is different too, in the sense that they are
% prepositioned i.e. are already raised. (In my opinion for no real reason as they
% need to adapt anyway).
%
% $ \ruledhbox{$H$}  \hat{H}  \ruledhbox{$\widehat{H}$}  \widehat{H} $
%
% One alternative is:
%
% \definemathoverextensible [top] [hoed]  ["FE302]
% \definemathoverextensible [top] [slang] ["FE303]
%
% $ \hoed{H} \ruledhbox{$\hoed{H}$}  \ruledhbox{$\hoed{\tf H}$}  \slang{H} $
%
% But that nills the italic correction (and I'm in nood to mess with that again).
%
% \definemathaccents   [myaccents] [color=darkred]
% \definemathtopaccent [myaccents] [mywidehat] ["0302]
%
% $ \hat{H}  \widehat{H}  \mywidehat{H} $

% A first variant (kept for educational purposed):
%
% \installcorenamespace{mathaccents}
%
% \installcommandhandler \??mathaccents {mathaccent} \??mathaccents
%
% \let\setupmathaccents\setupmathaccent
%
% \setupmathaccents
%   [\c!top=,
%    \c!bottom=,
%    \c!mathstyle=,
%    \c!color=,
%    \c!command=\v!yes]
%
% \appendtoks
%     \edef\p_top_bottom{\namedmathaccentparameter\currentmathaccent\c!top\namedmathaccentparameter\currentmathaccent\c!bottom}%
%     \ifx\p_top_bottom\empty\else
%         \edef\p_command{\mathaccentparameter\c!command}%
%         \ifx\p_command\v!yes
%             \setuevalue\currentmathaccent{\math_accent{\currentmathaccent}}%
%         \fi
%     \fi
% \to \everydefinemathaccent
%
% \def\math_accented_color_do_push{\pushcolor[\p_math_accent_color]}
% \let\math_accented_color_do_pop  \popcolor
%
% \unexpanded\def\math_accent#1#2%
%   {\begingroup
%    \edef\currentmathaccent{#1}%
%    \edef\p_math_accent_top   {\mathaccentparameter\c!top}%
%    \edef\p_math_accent_bottom{\mathaccentparameter\c!bottom}%
%    \edef\p_math_accent_color {\mathaccentparameter\c!color}%
%    \startusemathstyleparameter\mathaccentparameter
%    \ifx\p_math_accented_color\empty
%      \let\math_accented_color_do_pop\donothing
%    \else
%      \let\math_accented_color_do_pop\popcolor
%      \math_accented_color_do_push
%    \fi
%    \ifx\p_math_accent_top\empty
%      \ifx\p_math_accent_bottom\empty
%      \else
%        \Umathaccent bottom \fam\zerocount\p_math_accent_bottom
%      \fi
%    \else
%      \ifx\p_math_accent_bottom\empty
%        \Umathaccent        \fam\zerocount\p_math_accent_top
%      \else
%        \Umathaccent both   \fam\zerocount\p_math_accent_top
%                            \fam\zerocount\p_math_accent_bottom
%      \fi
%    \fi
%    {\popcolor#2}%
%    \stopusemathstyleparameter
%    \endgroup}
%
% \definemathaccent [myaccents] [\c!color=red]
% \definemathaccent [mywidehat] [myaccents] [\c!top="0302]

\installcorenamespace{mathaccents}

\installcommandhandler \??mathaccents {mathaccents} \??mathaccents

\setupmathaccents
  [\c!top=,
   \c!bottom=,
   \c!mathstyle=,
   \c!color=,
   \c!command=\v!yes]

\definemathaccents
  [\v!both]

\definemathaccents
  [\v!top]
  [\v!both]

\definemathaccents
  [\v!bottom]
  [\v!both]

\unexpanded\def\definemathtopaccent   {\dotripleempty   \math_accents_define_top   }
\unexpanded\def\definemathbottomaccent{\dotripleempty   \math_accents_define_bottom}
\unexpanded\def\definemathdoubleaccent{\doquadrupleempty\math_accents_define_double}

\def\math_accents_define_top[#1][#2][#3]% class name top
  {\ifthirdargument
     \setuevalue{#2}{\math_accents_make_double                        {#1}\plusone{\number#3}\zerocount}%
   \else
     \setuevalue{#1}{\math_accents_make_double\noexpand\currentmathaccents\plusone{\number#2}\zerocount}%
   \fi}

\def\math_accents_define_bottom[#1][#2][#3]% class name bottom
  {\ifthirdargument
     \setuevalue{#2}{\math_accents_make_double                        {#1}\plustwo\zerocount{\number#3}}%
   \else
     \setuevalue{#1}{\math_accents_make_double\noexpand\currentmathaccents\plustwo\zerocount{\number#2}}%
   \fi}

\def\math_accents_define_double[#1][#2][#3][#4]% class name top bottom
  {\iffourthargument
     \setuevalue{#2}{\math_accents_make_double                        {#1}\plusthree{\number#3}{\number#4}}%
   \else
     \setuevalue{#1}{\math_accents_make_double\noexpand\currentmathaccents\plusthree{\number#2}{\number#3}}%
   \fi}

\def\math_accents_color_push_yes
  {\pushcolor[\p_math_accent_color]%
   \let\math_accents_color_pop\popcolor}

\def\math_accents_color_push_nop
  {\let\math_accents_color_pop\donothing}

\unexpanded\def\math_accents_make_double#class#kind#top#bottom#content%
  {\begingroup
   \edef\currentmathaccents {#class}%
   \edef\p_math_accent_color{\mathaccentsparameter\c!color}%
   \startusemathstyleparameter\mathaccentsparameter
   \ifx\p_math_accent_color\empty
     \math_accents_color_push_nop
   \else
     \math_accents_color_push_yes
   \fi
   \ifcase#kind\or
     \Umathaccent        \fam\zerocount#top
   \or
     \Umathaccent bottom \fam\zerocount#bottom
   \or
     \Umathaccent both   \fam\zerocount#top
                         \fam\zerocount#bottom
   \fi
   {\math_accents_color_pop#content}%
   \stopusemathstyleparameter
   \endgroup}

%D Relative new:

\newconditional\c_math_accents_auto_dotless \settrue\c_math_accents_auto_dotless % cf opentype math

\let\normalgrave   \grave      \unexpanded\def\dotlessgrave   #1{\normalgrave   {\mathdotless#1}}
\let\normalddot    \ddot       \unexpanded\def\dotlessddot    #1{\normalddot    {\mathdotless#1}}
\let\normalbar     \bar        \unexpanded\def\dotlessbar     #1{\normalbar     {\mathdotless#1}}
\let\normalacute   \acute      \unexpanded\def\dotlessacute   #1{\normalacute   {\mathdotless#1}}
\let\normalhat     \hat        \unexpanded\def\dotlesshat     #1{\normalhat     {\mathdotless#1}}
\let\normalcheck   \check      \unexpanded\def\dotlesscheck   #1{\normalcheck   {\mathdotless#1}}
\let\normalbreve   \breve      \unexpanded\def\dotlessbreve   #1{\normalbreve   {\mathdotless#1}}
\let\normaldot     \dot        \unexpanded\def\dotlessdot     #1{\normaldot     {\mathdotless#1}}
\let\normalmathring\mathring   \unexpanded\def\dotlessmathring#1{\normalmathring{\mathdotless#1}}
\let\normaltilde   \tilde      \unexpanded\def\dotlesstilde   #1{\normaltilde   {\mathdotless#1}}
\let\normaldddot   \dddot      \unexpanded\def\dotlessdddot   #1{\normaldddot   {\mathdotless#1}}

\def\math_accents_auto_dotless#1#2%
  {\ifconditional\c_math_accents_auto_dotless\expandafter#2\else\expandafter#1\fi}

\unexpanded\def\grave   {\math_accents_auto_dotless\normalgrave   \dotlessgrave   }
\unexpanded\def\ddot    {\math_accents_auto_dotless\normalddot    \dotlessddot    }
\unexpanded\def\bar     {\math_accents_auto_dotless\normalbar     \dotlessbar     }
\unexpanded\def\acute   {\math_accents_auto_dotless\normalacute   \dotlessacute   }
\unexpanded\def\hat     {\math_accents_auto_dotless\normalhat     \dotlesshat     }
\unexpanded\def\check   {\math_accents_auto_dotless\normalcheck   \dotlesscheck   }
\unexpanded\def\breve   {\math_accents_auto_dotless\normalbreve   \dotlessbreve   }
\unexpanded\def\dot     {\math_accents_auto_dotless\normaldot     \dotlessdot     }
\unexpanded\def\mathring{\math_accents_auto_dotless\normalmathring\dotlessmathring}
\unexpanded\def\tilde   {\math_accents_auto_dotless\normaltilde   \dotlesstilde   }
\unexpanded\def\dddot   {\math_accents_auto_dotless\normaldddot   \dotlessdddot   }

\protect \endinput
