%D \module
%D   [       file=phys-dim,
%D        version=2011-06-13, % was digits and units 1997.03.19,
%D          title=\CONTEXT\ Physics,
%D       subtitle=Digits and Units,
%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.

\registerctxluafile{phys-dim}{}

\unprotect

%D \macros
%D   {digits, setdigitmode, setdigitsign}
%D
%D This is an update of the \MKII\ digits mechanism. Beware,
%D space delimited mode is now resticted!
%D
%D Depending on the digit mode the command \type {\digits}
%D normalizes number patterns depending on the language set.
%D
%D \starttyping
%D This will never be a \digits{1.000.000} seller.
%D \stoptyping
%D
%D We still support the space delimited case but this is only for special
%D purposes. When used in the text, you'd better use the argument variant.
%D
%D \startbuffer
%D 1 \setdigitmode {1} \setdigitorder{0} \digits {12.345,90}
%D 2 \setdigitmode {2} \setdigitorder{0} \digits {12.345,90}
%D 3 \setdigitmode {3} \setdigitorder{0} \digits {12.345,90}
%D 4 \setdigitmode {4} \setdigitorder{0} \digits {12.345,90}
%D 5 \setdigitmode {5} \setdigitorder{0} \digits {12.345,90}
%D 6 \setdigitmode {6} \setdigitorder{0} \digits {12.345,90}
%D 1 \setdigitmode {1} \setdigitorder{1} \digits {12.345,90}
%D 2 \setdigitmode {2} \setdigitorder{1} \digits {12.345,90}
%D 3 \setdigitmode {3} \setdigitorder{1} \digits {12.345,90}
%D 4 \setdigitmode {4} \setdigitorder{1} \digits {12.345,90}
%D 5 \setdigitmode {5} \setdigitorder{1} \digits {12.345,90}
%D 6 \setdigitmode {6} \setdigitorder{1} \digits {12.345,90}
%D \stopbuffer
%D
%D \typebuffer
%D
%D This is typeset as:
%D
%D \startlines \getbuffer \stoplines
%D
%D The sign can be typeset as is or within the space of a
%D digit.
%D
%D \startbuffer
%D \setdigitsign 0 \digits {+12.345,90}
%D \setdigitsign 1 \digits {+12.345,90}
%D \stopbuffer
%D
%D \typebuffer
%D
%D This is typset as:
%D
%D \startlines
%D \getbuffer
%D \stoplines
%D
%D The digit modes are:
%D
%D \startitemize[n,packed]
%D \item periods/comma
%D \item commas/period
%D \item thinmuskips/comma
%D \item thinmuskips/period
%D \item thickmuskips/comma
%D \item thickmuskips/period
%D \stopitemize
%D
%D The digit parser handles a bunch of special characters as
%D well as different formats. We strongly suggest you to use
%D the grouped call.
%D
%D \starttabulate[|l|l|l|]
%D \NC \type{.} \NC , .           \NC comma or period            \NC \NR
%D \NC \type{,} \NC , .           \NC comma or period            \NC \NR
%D \NC \type{@} \NC               \NC invisible space            \NC \NR
%D \NC \type{_} \NC               \NC invisible space            \NC \NR
%D \NC \type{/} \NC               \NC invisible sign             \NC \NR
%D \NC \type{-} \NC $-$           \NC minus sign                 \NC \NR
%D \NC \type{+} \NC $+$           \NC plus sign                  \NC \NR
%D \NC \type{s} \NC               \NC invisible high sign        \NC \NR
%D \NC \type{p} \NC $\positive$   \NC high plus sign             \NC \NR
%D \NC \type{m} \NC $\negative$   \NC high minus sign            \NC \NR
%D \NC \type{n} \NC $\negative$   \NC high minus (negative) sign \NC \NR
%D \NC \type{=} \NC $\zeroamount$ \NC zero padding               \NC \NR
%D \stoptabulate
%D
%D These triggers are used in the following examples.
%D
%D \startbuffer
%D \digits{12}
%D \digits{~~~.~~~.~~~.68.712,34}
%D \digits{___.___.111.68.712,34}
%D \digits{111.111.111.68.712,34}
%D \digits{12.345,90}
%D \digits{12.345.000}
%D \digits{12,34}
%D \digits{392.857.230.68.712,34}
%D \digits{1234}
%D \digits{123.222,00}
%D \digits{123.222,==}
%D \digits{123.222,00^10}
%D \digits{123.222,00e10}
%D \digits{/123.222,00e-12}
%D \digits{-123.222,00e-12}
%D \digits{+123.222,00e-12}
%D \digits{n123.222,00e-12}
%D \digits{s123.222,00e-12}
%D \digits{p123.222,00e-12}
%D \stopbuffer
%D
%D \typebuffer
%D
%D \startlines
%D \getbuffer
%D \stoplines

\newconstant\c_digits_order
\newconstant\c_digits_method
\newconstant\c_digits_sign  % we has sized (text script scriptscript)

\def\setdigitmethod#1{\c_digits_method #1\relax}
\def\setdigitsign  #1{\c_digits_sign   #1\relax}
\def\setdigitorder #1{\c_digits_order  #1\relax}

\let\setdigitmode\setdigitmethod % compatibility

\def\digits_normalized % we could calculate once and remember
  {\ifcase\c_digits_sign
     \expandafter\secondoftwoarguments
   \else\ifmmode
     \expandafter\expandafter\expandafter\digits_normalized_math
   \else
     \expandafter\expandafter\expandafter\digits_normalized_text
   \fi\fi}

\def\digits_normalized_math#1#2%
  {\setbox\scratchbox\hbox{$\Ustack{#1}$}%
   \hbox to \wd\scratchbox{\hss{$\Ustack{#2}$}\hss}}

\def\digits_normalized_text#1#2%
  {\setbox\scratchbox\hbox{#1}%
   \hbox to \wd\scratchbox{\hss#2\hss}}

\def\digits_raised
  {\ifmmode
     \expandafter\normalsuperscript
   \else
     \expandafter\high
   \fi}

\def\digitszeropadding   {\zeroamount}
\def\digitsnegative      {\digits_normalized{0}{\digits_raised{\textminus}}}
\def\digitspositive      {\digits_normalized{0}{\digits_raised{\textplus}}}
\def\digitsnegative      {\digits_normalized{0}{\mathematics{\negative}}}
\def\digitspositive      {\digits_normalized{0}{\mathematics{\positive}}}
\def\digitsminus         {\digits_normalized{0}{\mathematics{-}}}
\def\digitsplus          {\digits_normalized{0}{\mathematics{+}}}
\def\digitsspace         {\hphantom{0}}
\def\digitsseparatorspace{\hphantom{.}}
\def\digitssignspace     {\hphantom{\digitsminus}}
\def\digitshighspace     {\hphantom{\digitspositive}}
\def\digitspower         {\digits_raised}
\def\digitspowerplus   #1{\digits_raised{\digitsplus#1}}
\def\digitspowerminus  #1{\digits_raised{\digitsminus#1}}
\def\digitsdigit       #1{#1}

\def\normaldigitscommasymbol   {,}
\def\normaldigitsperiodsymbol  {.}
\let\normaldigitsseparatorspace\digitsseparatorspace

\letvalue{digit_c_0}\normaldigitscommasymbol
\letvalue{digit_p_0}\normaldigitsperiodsymbol
\letvalue{digit_s_0}\normaldigitsseparatorspace

\letvalue{digit_c_1}\normaldigitsperiodsymbol
\letvalue{digit_p_1}\normaldigitscommasymbol
\letvalue{digit_s_1}\normaldigitsseparatorspace

\letvalue{digit_c_2}\normaldigitscommasymbol
\letvalue{digit_p_2}\normaldigitsperiodsymbol
\letvalue{digit_s_2}\normaldigitsseparatorspace

\letvalue{digit_c_3}\thinspace
\letvalue{digit_p_3}\normaldigitscommasymbol
\letvalue{digit_s_3}\thinspace

\letvalue{digit_c_4}\thinspace
\letvalue{digit_p_4}\normaldigitsperiodsymbol
\letvalue{digit_s_4}\thinspace

\letvalue{digit_c_5}\thickspace
\letvalue{digit_p_5}\normaldigitscommasymbol
\letvalue{digit_s_5}\thickspace

\letvalue{digit_c_6}\thickspace
\letvalue{digit_p_6}\normaldigitsperiodsymbol
\letvalue{digit_s_6}\thickspace

\def\digitscommasymbol         {\csname digit_c_\number\c_digits_method\endcsname}
\def\digitsperiodsymbol        {\csname digit_p_\number\c_digits_method\endcsname}
\def\digitsseparatorspace      {\csname digit_s_\number\c_digits_method\endcsname}

\def\digitsfinalcomma          {\digitscommasymbol } % more for tracing
\def\digitsfinalperiod         {\digitsperiodsymbol} % more for tracing
\def\digitsintermediatecomma   {\digitscommasymbol } % more for tracing
\def\digitsintermediateperiod  {\digitsperiodsymbol} % more for tracing

%D The user macro:

\unexpanded\def\digits_indeed#1%
  {\dontleavehmode
   \begingroup
   \ctxcommand{digits(\!!bs\detokenize{#1}\!!es,"\ifcase\c_digits_order \v!normal\else\v!reverse\fi")}%
   \endgroup
   \settrue\c_units_dospace}

\unexpanded\def\digits
  {\doifnextbgroupelse\digits_argument\digits_spaced}

\def\digits_argument#1%
  {\digits_indeed{#1}}

\def\digits_spaced#1 % space delimited
  {\digits_indeed{#1}}

%D \macros
%D   {unit}
%D
%D We have been using the units module (and its predecessor) for over a decade
%D now but when we moved on to \LUATEX\ a variant was prototyped that permits a
%D less texie coding. I finally picked up that thread and cleaned up the code a
%D bit so users can now play with it. (The main reason was that I wanted to
%D test exporting.)
%D
%D \startbuffer
%D 01: $10\unit{km/h}$
%D 02: $\unit{10      km/h}$
%D 03: \unit{km/h}
%D 04: \unit{10 km/h}
%D 05: \unit{10 km/h}
%D 06: \unit{~1 km/h}
%D 07: 10\unit{km/h}
%D 08: 10 \unit{km/h}
%D 09: $10 \unit{km/h}$
%D 10: 10 \unit{KiloMeter/Hour}
%D 11: 10 \unit{kilometer/hour}
%D 12: 10 \unit{km/h}
%D 13: 10 \unit{kilometer per hour}
%D 14: 10 \unit{km / h}
%D 15: 10 \unit{ km / h }
%D 16: 10 \unit{km/ms2}
%D 17: 10 \unit{meter per second}
%D 18: 10 \unit{cubic meter}
%D 19: 10 \unit{cubic meter per second}
%D 21: 10 \unit{cubic meter / second}
%D 22: $10 \unit{cubic meter / second}$
%D 23: 30 \unit{kilo pascal }
%D 24: 30 \unit{kilo pascal square meter / second}
%D 25: 30 \unit{kilo pascal square meter / kelvin second}
%D 26: \unit{30 kilo pascal square meter / kelvin second}
%D 27: $30 \unit{kilo pascal square meter / kelvin second }$
%D 28: 30 \unit{crap}
%D 29: 30 \unit{AC}
%D 30: $\frac{10 \unit{m/s}}{20 \unit{m/s}} $
%D 31: {\ss 30 \unit{kilo pascal square meter / second kelvin}}
%D 32: \unit{123.22^-3 km/s}
%D 33: \unit{123.22e-3 km/s}
%D \stopbuffer
%D
%D \typebuffer
%D
%D Result: \startlines \getbuffer \stoplines
%D
%D Depending on needs we can add more tweaks (also depends on to what
%D extent we need to be compatible with \MKII.
%D
%D Formatting is supported too:
%D
%D \startbuffer
%D \starttabulate[|l|l|l|]
%D \HL
%D \NC \unit{10 kilo gram}       \NC \digits{10}        \NC \unit{10}        \NC \NR
%D \NC \unit{1 kilogram}         \NC \digits{1}         \NC \unit{1}         \NC \NR
%D \NC \unit{0.1 kilogram}       \NC \digits{0.1}       \NC \unit{0.1}       \NC \NR
%D \NC \unit{1.1 kilogram}       \NC \digits{1.1}       \NC \unit{1.1}       \NC \NR
%D \NC \unit{11 kilogram}        \NC \digits{11}        \NC \unit{11}        \NC \NR
%D \HL
%D \NC \unit{00,000.10 kilogram} \NC \digits{00,000.10} \NC \unit{00,000.10} \NC \NR
%D \NC \unit{@@,@@0.10 kilogram} \NC \digits{@@,@@0.10} \NC \unit{@@,@@0.10} \NC \NR
%D \NC \unit{__,___.10 kilogram} \NC \digits{__,___.10} \NC \unit{__,___.10} \NC \NR
%D \NC \unit{__,__0:10 kilogram} \NC \digits{__,__0:10} \NC \unit{__,__0:10} \NC \NR
%D \NC \unit{__,___:10 kilogram} \NC \digits{__,___:10} \NC \unit{__,___:10} \NC \NR
%D \HL
%D \stoptabulate
%D \stopbuffer
%D
%D \typebuffer \getbuffer
%D
%D Punctuation can be configures usiing \type {method}:
%D
%D \startbuffer
%D \starttabulate[|l|l|l|]
%D \HL
%D \NC   \NC \setupunits[method=0]\unit{00,000.10 kilogram} \NC \setupunits[method=0]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 1 \NC \setupunits[method=1]\unit{00,000.10 kilogram} \NC \setupunits[method=1]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 2 \NC \setupunits[method=2]\unit{00,000.10 kilogram} \NC \setupunits[method=2]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 3 \NC \setupunits[method=3]\unit{00,000.10 kilogram} \NC \setupunits[method=3]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 4 \NC \setupunits[method=4]\unit{00,000.10 kilogram} \NC \setupunits[method=4]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 5 \NC \setupunits[method=5]\unit{00,000.10 kilogram} \NC \setupunits[method=5]\unit{@@,@@0.10 kilogram} \NC \NR
%D \NC 6 \NC \setupunits[method=6]\unit{00,000.10 kilogram} \NC \setupunits[method=6]\unit{@@,@@0.10 kilogram} \NC \NR
%D \HL
%D \stoptabulate
%D \stopbuffer
%D
%D \typebuffer \getbuffer

% only a space when a number is part of the unit

\installcommandhandler \??un {units} \??un

\setupunits
  [\c!alternative=,        % done: text
   \c!separator=\v!normal, % done: cdot|big|medium|space
   \c!label=,              % done: (no interface yet)
   \c!order=\v!normal,     % ,. (reverse: .,)
   \c!method=0,
  %\c!grid=\v!yes,         % (maybe)
  %\c!style=...,           % done
  %\c!color=...,           % done
  %\c!space=...,           % (maybe) small medium big
  ]

\newconstant   \c_units_mode   % 0=text 1=math 2=textinmath 3=mathintext
\newconstant   \c_units_state  % 0=start 1=suffix 2=operator 3=unit 4=prefix 5=number
\newconditional\c_units_quantity
\newconditional\c_units_number
\newconditional\c_units_dospace

% [\unit   {micro ohm}]\par %  no space before unit
% [10\unit {micro ohm}]\par %  no space before unit
% [10 \unit{micro ohm}]\par %     space before unit
% [ \unit  {micro ohm}]\par %     space before unit
% [\unit{10 micro ohm}]\par %     space before unit

\def\unitssmallspace {\thinspace}
\def\unitsmediumspace{\medspace}
\def\unitsbigspace   {\thickspace}
\def\unitsbackspace  {\negthinspace}

\def\installunitsseparator#1#2%
  {\setvalue{\??un::#1}{#2}}

\unexpanded\def\dounitsseparator
  {\edef\currentunitsseparator{\unitsparameter\c!separator}%
   \csname\??un::%
     \ifcsname\??un::\currentunitsseparator\endcsname\currentunitsseparator\else\v!normal\fi
   \endcsname}

\installunitsseparator\v!normal {\cdot}
\installunitsseparator\v!big    {\unitsbigspace}
\installunitsseparator\v!medium {\unitsmediumspace}
\installunitsseparator\v!small  {\unitssmallspace}
\installunitsseparator\v!none   {}

\newtoks \everyunits % we keep the old \units command so we need a longer one

\appendtoks
    \setuevalue\currentunits{\units_direct{\currentunits}}
\to \everydefineunits

\unexpanded\def\units_direct#1%
  {\begingroup
   \ifdim\lastskip>\zeropoint
     \settrue\c_units_dospace
     \removelastskip
   \fi
   \c_digits_method\unitsparameter\c!method\relax
   \ifmmode\else\dontleavehmode\fi
   \edef\currentunits{#1}%
   \the\everyunits
  %\removeunwantedspaces % now ok yet
   \dosetunitsattributes\c!style\c!color
   \edef\currentunitsalternative{\unitsparameter\c!alternative}%
   \ifmmode
     \ifx\currentunitsalternative\v!text
       \expandafter\expandafter\expandafter\units_direct_text_in_math
     \else
       \expandafter\expandafter\expandafter\units_direct_math
     \fi
   \else
     \ifx\currentunitsalternative\v!mathematics
       \expandafter\expandafter\expandafter\units_direct_math_in_text
     \else
       \expandafter\expandafter\expandafter\units_direct_text
     \fi
   \fi}

\unexpanded\def\units_direct_text_in_math#1%
  {\mathtext{%
     \c_units_mode\plustwo
     \units_indeed{#1}%
     \units_finish
   }%
   \endgroup}

\unexpanded\def\units_direct_math#1%
  {\c_units_mode\plusone
   \rm\tf
   \mathtf
   \units_indeed{#1}%
   \units_finish
   \endgroup}

\unexpanded\def\units_direct_text#1%
  {\units_indeed{#1}%
   \units_finish
   \endgroup}

\unexpanded\def\units_direct_math_in_text#1%
  {\removeunwantedspaces % brr
   \startimath
   \c_units_mode\plusthree
   \rm\tf
   \mathtf
   \units_indeed{#1}%
   \units_finish
   \stopimath
   \endgroup}

\unexpanded\def\units_direct_nested#1#2%
  {\units_indeed{#2}}

\appendtoks
    \let\units_direct\units_direct_nested
\to \everyunits

\unexpanded\def\units_indeed#1{\ctxcommand{unit(\!!bs\detokenize{#1}\!!es,"\unitsparameter\c!label","\unitsparameter\c!order")}}

\unexpanded\def\unitsPUS#1#2#3{\units_next#1#2\unitsraise{#3}\c_units_state\plusone}   % suffix
\unexpanded\def\unitsPU   #1#2{\units_next#1#2\c_units_state               \plusthree} % unit
\unexpanded\def\unitsPS   #1#2{\units_next#1\unitsraise{#2}\c_units_state  \plusone}   % suffix
\unexpanded\def\unitsUS   #1#2{\units_next#1\unitsraise{#2}\c_units_state  \plusone}   % suffix
\unexpanded\def\unitsP      #1{\units_next#1\c_units_state                 \plusfour}  % prefix
\unexpanded\def\unitsU      #1{\units_next#1\c_units_state                 \plusthree} % unit
\unexpanded\def\unitsS      #1{\units_start{}\unitsraise{#1}\c_units_state \plusone}   % suffix
\unexpanded\def\unitsO      #1{\units_start#1\c_units_state                \plustwo}   % operator
\unexpanded\def\unitsN      #1{\units_start#1\c_units_state                \plusfive}  % number

\setelementnature[unit]    [mixed]
\setelementnature[quantity][mixed]

\let\units_finish\relax

\unexpanded\def\unitsNstart
  {\ifmmode \else
     \settrue\c_units_quantity
     \dostarttagged\t!quantity\empty
     \settrue\c_units_number
     \dostarttagged\t!number\empty
   \fi}

\unexpanded\def\unitsNstop
  {\ifconditional\c_units_number
     \setfalse\c_units_number
     \dostoptagged
   \fi
   \c_units_state\plusfive}

\unexpanded\def\unitsN#1%
  {\unitsNstart#1\unitsNstop}

\def\units_start
  {\ifmmode
     \dostarttagged\t!mathaction\t!unit
     \bgroup % make an mrow
   \else
     \dostarttagged\t!unit\empty
   \fi
   \let\units_finish\units_stop
   \let\units_start\relax}

\def\units_stop
  {\ifconditional\c_units_number
     \setfalse\c_units_number
     \dostoptagged
   \fi
   \ifconditional\c_units_quantity
     \setfalse\c_units_quantity
     \dostoptagged
   \fi
   \dostoptagged
   \ifmmode
     \egroup
   \fi}

\def\unitsraise
  {\ifcase\c_units_mode
     \expandafter\high
   \or
     \expandafter\normalsuperscript
   \or
     \expandafter\high
   \or
     \expandafter\normalsuperscript
   \fi}

\def\unitslower
  {\ifcase\c_units_mode
     \expandafter\low
   \or
     \expandafter\normalsubscript
   \or
     \expandafter\low
   \or
     \expandafter\normalsubscript
   \fi}

\unexpanded\def\units_next
  {\ifcase\c_units_state % start
     \ifconditional\c_units_dospace
      % \ifdim\lastskip=\zeropoint
         \unitsbigspace
      % \else
      %   % too tricky ... we could remove and add
      % \fi
     \fi
   \or % suffix
     {\dounitsseparator}%
   \or % operator
   \or % unit
     {\dounitsseparator}%
   \or % prefix
   \or % number
     \unitsbigspace
   \fi
   \setfalse\c_units_dospace
   \units_start}

\unexpanded\def\unitsTIMES
  {\ifnum\c_units_state=\plusone % suffix
   \else
     \unitssmallspace
   \fi
   \cdot} % or \times

\unexpanded\def\unitsOUTOF
  {\ifnum\c_units_state=\plusone % suffix
   \else
     \unitssmallspace
   \fi
   :}

\unexpanded\def\unitsSOLIDUS
  {\ifnum\c_units_state=\plusone % suffix
     \unitsbackspace
   \fi
   {/}%
   }%\unitsbackspace}

%D Now we define the standard units command:

\defineunits
  [unit]

%D Example:
%D
%D \startbuffer[definitions]
%D \startluacode
%D     languages.data.labels.prefixes.whatever = {
%D         Kilo = "olik"
%D     }
%D
%D     languages.data.labels.units.whatever = {
%D         Meter  = "retem",
%D         Second = "dnoces",
%D     }
%D
%D     languages.data.labels.operators.whatever = {
%D         Solidus = " rep "
%D     }
%D \stopluacode
%D \stopbuffer
%D
%D \startbuffer[sample]
%D \startlines
%D \lunit{10 km/s}
%D \lunit{10 Kilo Meter/s}
%D \lunit{10 kilo Meter/s}
%D \lunit{10 Kilo m/s}
%D \lunit{10 k Meter/s}
%D \stoplines
%D \stopbuffer
%D
%D \typebuffer[definitions] \getbuffer[definitions]
%D
%D \startbuffer
%D \typebuffer[sample]
%D
%D \defineunits[lunit]                 \getbuffer[sample]
%D \defineunits[lunit][label=test]     \getbuffer[sample]
%D \defineunits[lunit][label=whatever] \getbuffer[sample]
%D \stopbuffer
%D
%D \typebuffer \getbuffer

\protect \endinput