%D \module
%D   [       file=scrn-nav,
%D        version=1998.01.15,
%D          title=\CONTEXT\ Screen Macros,
%D       subtitle=Navigation,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
%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 Screen Macros / Navigation}

\unprotect

%D Support for interactive document is very present in
%D \CONTEXT\ and interwoven in many modules. This means that in
%D this module, where we deal with some common navigational
%D features, there will be quite some forward references.
%D
%D The current support in \MKIV\ is mostly the same as in
%D \MKII\ and the old files have some more detailed
%D (sometimes historic) information.

%D There is no interaction at all unless enabled by saying:
%D
%D \starttyping
%D \setupinteraction[state=start]
%D \stoptyping
%D
%D The other settings are:
%D
%D \showsetup{setupinteraction}

% use with care, no checking done

\def\setinteractionparameter#1#2%
  {\expandafter\def\csname\??ia#1\endcsname{#2}}

\def\resetinteractionparameter#1%
  {\expandafter\let\csname\??ia#1\endcsname\empty}

\newtoks\everysetupinteraction

\unexpanded\def\setupinteraction
  {\dosingleargument\dodosetupinteraction}

\def\dodosetupinteraction[#1]% % \dosetupinteraction == special
  {\getparameters[\??ia][#1]%
   \the\everysetupinteraction}

% todo, move partial append to where the action happens

\appendtoks
  \doifelse\@@iastate\v!start
    {\iflocation\else
       \showmessage\m!interactions2{\ifusepagedestinations\space(PAGE)\fi}%
       \global\locationtrue
     \fi}%
    {\iflocation
       \showmessage\m!interactions3{\ifusepagedestinations\space(PAGE)\fi}%
       \global\locationfalse
     \fi}%
  \iflocation
    \setsystemmode  \v!interaction
  \else
    \resetsystemmode\v!interaction
  \fi
  \doifsomething\@@iacalculate
    {\doregistercalculationset\@@iacalculate}%
  \doifelse\@@iastrut  \v!yes \settrue \setfalse \uselocationstrut
  \doifelse\@@iaclick  \v!yes \settrue \setfalse \highlighthyperlinks
  \doifelse\@@iadisplay\v!new \settrue \setfalse \gotonewwindow
  \doifelse\@@iapage   \v!yes \settrue \setfalse \usepagedestinations
\to \everysetupinteraction

\def\synchronizebackendidentity
  {\ctxlua{backends.codeinjections.setupidentity{
     title    = \!!bs\@@iatitle\!!es,
     subject  = \!!bs\@@iasubtitle\!!es,
     author   = \!!bs\@@iaauthor\!!es,
     creator  = \!!bs ConTeXt - \contextversion\!!es,
     date     = \!!bs\@@iadate\!!es,
     keywords = \!!bs\@@iakeyword\!!es,
  }}}

\appendtoks
  \synchronizebackendidentity
\to \everyfirstshipout

%D We have to make sure of some settings:

\def\dolocationstartup
  {\iflocation
     \donefalse
     \ifx\@@iaopenaction\empty \else \donetrue
        \ctxlua{jobreferences.checkopendocumentactions("\@@iaopenaction")}%
        \ctxlua{jobreferences.expandcurrent()}%
     \fi
     \ifx\@@iacloseaction\empty \else \donetrue
        \ctxlua{jobreferences.checkclosedocumentactions("\@@iacloseaction")}%
        \ctxlua{jobreferences.expandcurrent()}%
     \fi
     \ifdone
        \ctxlua{jobreferences.flushdocumentactions()}%
     \fi
     \global\let\dolocationstartup\relax
   \fi}

\def\dolocationpagecheck
  {\iflocation
     \donefalse
     \ifx\@@iaopenpageaction\empty \else \donetrue
        \ctxlua{jobreferences.checkopenpageactions("\@@iaopenpageaction")}%
        \ctxlua{jobreferences.expandcurrent()}%
     \fi
     \ifx\@@iaclosepageaction\empty \else \donetrue
        \ctxlua{jobreferences.checkclosepageactions("\@@iaclosepageaction")}%
        \ctxlua{jobreferences.expandcurrent()}%
     \fi
     \ifdone
        \ctxlua{jobreferences.flushpageactions()}%
     \fi
   \fi}

\appendtoks \dolocationstartup   \to \everyshipout
\appendtoks \dolocationpagecheck \to \everyshipout

%D As long as there a natural feeling of what can be considered
%D hyper active or not, we have to tell users where they can
%D possibly click. We've already seen a few macros that deal
%D with this visualization, something we definitely do not let
%D up to the viewer. One way of telling is using a distinctive
%D typeface, another way is using color.
%D
%D There are two colors involved: one for normal hyperlinks,
%D and one for those that point to the currentpage, the
%D contrast color.

\definecolor [interactioncolor]         [r=0,  g=.6, b=0]
\definecolor [interactioncontrastcolor] [r=.8, g=0,  b=0]

\definecolor [interactiekleur]          [interactioncolor]
\definecolor [interactiecontrastkleur]  [interactioncontrastcolor]

%D The next few macros are responsible for highlighting hyper
%D links. The first one, \type{\showlocation}, is used in those
%D situations where the typeface is handled by the calling
%D macro.

%D When we're dealing with pure page references, contrast
%D colors are used when we are already at the page mentioned.

\def\setlocationcolor#1% not grouped !
  {\ifnum\referencepagestate=\plusone
     \edef\askedcontrastcolor{\csname#1\c!contrastcolor\endcsname}%
     \ifx\askedcontrastcolor\empty
       \dosetcolorattribute{#1}\c!color
     \else
       \dosetcolorattribute{#1}\c!contrastcolor
     \fi
   \else % we could just set and if > 0 set again
     \dosetcolorattribute{#1}\c!color
   \fi}

\def\setlocationfont#1%
  {\dosetfontattribute{#1}\c!style}

\def\setlocationattributes#1%
  {\ifnum\referencepagestate=\plusone
     \edef\askedcontrastcolor{\csname#1\c!contrastcolor\endcsname}%
     \ifx\askedcontrastcolor\empty
       \dosetcolorattribute{#1}\c!color
     \else
       \dosetcolorattribute{#1}\c!contrastcolor
     \fi
   \else % we could just set and if > 0 set again
     \dosetcolorattribute{#1}\c!color
   \fi
   \dosetfontattribute{#1}\c!style}

\def\setlocationcolorspec#1% \resolver
  {\ifnum\referencepagestate=\plusone
     \edef\askedcontrastcolor{#1\c!contrastcolor}%
     \ifx\askedcontrastcolor\empty
       \doactivatecolor{#1\c!color}%
     \else
       \doactivatecolor\askedcontrastcolor
     \fi
   \else
     \doactivatecolor{#1\c!color}%
   \fi}

%D delayed ...

\def\enableinteractivereferences
  {\ifproductionrun
     \ctxlua{jobreferences.enable_interaction()}%
     \globallet\enableinteractivereferences\relax
   \fi}

\appendtoks
    \enableinteractivereferences
\to \everysetupinteraction

%D More tokens are spend when we want both typeface and color
%D highlighting.

\def\@@iatimestamp
  {\the\normalyear
   \ifnum\normalmonth<10 0\fi\the\normalmonth
   \ifnum\normalday  <10 0\fi\the\normalday}

\setupinteraction % start fit page and reset form
  [\c!state=\v!stop,
   \c!page=\v!no,
   \c!click=\v!yes,
   \c!display=,
   \c!openaction=,
   \c!closeaction=,
   \c!openpageaction=,
   \c!closepageaction=,
   \c!display=\v!normal,
   \c!focus=\v!fit,
   \c!menu=\v!off,
   \c!style=\v!bold,
   \c!calculate=,
   \c!strut=\v!yes,
   \c!split=\v!yes,
   \c!color=interactioncolor,
   \c!contrastcolor=interactioncontrastcolor,
   \c!symbolset=,
   \c!width=1em,
   \c!height=\!!zeropoint,
   \c!depth=\!!zeropoint,
   \c!title=\jobname, % needed for fdf/x
   \c!subtitle=,
   \c!author=,
   \c!keyword=,
   \c!date=\@@iatimestamp]

%D XMP support:

\setupinteraction
  [xmpfile=]

\appendtoks
    % this will move as it is a backend issue
    \doifsomething\@@iaxmpfile
      {\ctxlua{if lpdf then lpdf.setxmpfile("\@@iaxmpfile") end}%
       \globallet\@@iaxmpfile\empty}%
\to \everysetupinteraction

\protect \endinput