%D \module
%D   [       file=java-imp-steps, % was: java-stp
%D        version=2004.03.15,
%D          title=\CONTEXT\ JavaScript Macros,
%D       subtitle=Stepping,
%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.

% we define ocglist global, otherwise we quickly run into a memory hog (even
% out of memory in a 512 Meg machine)

% we cannot use doc_visited[this.pageNum] instead of doc_currentstep because
% of some funny side effect (i.e. dup or so)

% todo: test with later as we do autoinsert now

\startJSpreamble Steps used now

var doc_ocglist     = this.getOCGs() ;
var doc_stepname    = "step" ;
var doc_currentstep =  0 ;
var doc_maxstep     = 50 ;
var doc_visited     = new Array() ;
var doc_busy        = new Array() ;

function SetupStepper(layername,laststep) {
    doc_stepname = layername ;
    doc_maxstep  = laststep ;
    for (var i=0; i<=this.numPages; i++) {
        doc_visited[i] = 0 ;
        doc_busy[i] = 0 ;
    }
}

for (var i=0; i<=this.numPages; i++) {
    doc_visited[i] = 0 ;
    doc_busy[i] = 0 ;
}

function GetOCG(name) {
    for (var i=0; i < doc_ocglist.length; i++) {
        if (doc_ocglist[i].name == name) {
            return doc_ocglist[i] ;
        }
    }
    return null ;
}

function CheckBusy() {
     var ocg = GetOCG("step:busy") ;
     if (ocg != null) {
         if (doc_visited[this.pageNum]==0) {
             ocg.state = true ;
         } else {
             if (doc_visited[this.pageNum]<doc_busy[this.pageNum]) {
                 ocg.state = true ;
             } else {
                 ocg.state = false ;
             }
         }
     }
}

function SetStepper(maxstep,state) {
    for (var i=1; i<=maxstep; i++) {
        try {
            var ocg = GetOCG(doc_stepname + ':' + String(i)) ;
            if (ocg != null) {
                ocg.state = state ;
            }
        } catch (e) {
            return ;
        }
    }
}

function CheckStepper(maxsteps) {
    SetStepper(doc_visited[this.pageNum], true) ;
    doc_busy[this.pageNum] = Number(maxsteps) ;
    doc_currentstep = doc_visited[this.pageNum] ;
    CheckBusy() ;
}

function ResetStepper() {
    SetStepper(doc_maxstep, false) ;
    doc_currentstep = 0 ;
}

function InvokeStepper() {
    try {
        if (doc_currentstep<doc_busy[this.pageNum]) {
            doc_currentstep += 1 ;
            doc_visited[this.pageNum] = doc_currentstep ;
            var ocg = GetOCG(doc_stepname + ':' + String(doc_currentstep)) ;
            if (ocg != null) {
                ocg.state = true ;
            }
        } else {
            if (this.pageNum+1==this.numPages) {
                this.pageNum  = 0 ;
            } else {
                this.pageNum += 1 ;
            }
        }
        CheckBusy() ;
    } catch (e) {
        return ;
    }
}

\stopJSpreamble

% \definereference [SetupStepper]  [JS(SetupStepper{step,50})]
% \definereference [ResetStepper]  [JS(ResetStepper)]
% \definereference [CheckStepper]  [JS(CheckStepper{\StepCounter})]
% \definereference [InvokeStepper] [JS(InvokeStepper)]

\endinput