Determine number of brushes with javascript

Question

I have the feeling it may have come up before (specifically in connection with rotating brushes), but I can’t locate it here or on PS-Scripts.com, so:
How can one determine the number of Brushes in Photoshop?
What I intend to use that information for is to save the last brush as a Set via JavaScript.
Any help appreciated.

Answer 1

Dang, once again I omitted to properly search xbytor’s code before posting.
»PresetLister.js« appears to contain the necessary elements …
Edit:
In case anyone else ever needs it, I tried to extract the parts relevant to this specific task from xbytor’s Script:
alert (loadBrushNames().length);
////// adapted from xbytor’s PresetLister.js //////
function loadBrushNames () {
cTID = function(s) { return app.charIDToTypeID(s); };
sTID = function(s) { return app.stringIDToTypeID(s); };
key = cTID('Brsh');
var names = [];
var classApplication = cTID('capp');
var typeOrdinal = cTID('Ordn');
var enumTarget = cTID('Trgt');
var ref = new ActionReference();
ref.putEnumerated(classApplication, typeOrdinal, enumTarget);
var appDesc = app.executeActionGet(ref);
var mgr = appDesc.getList(sTID('presetManager'));
var max = mgr.count;
for (var i = 0; i < max; i++) {
var objType = mgr.getObjectType(i);
if (objType == key) {
break;
if (i != max) {
var preset = mgr.getObjectValue(i);
var list = preset.getList(cTID('Nm  '));
var max = list.count;
for (var i = 0; i < max; i++) {
var str = list.getString(i);
names.push(str);
return names;