Painting Process Documentation: Stamp Visible, Move to layer Set and hide

Question

I like to capture my screen while painting and when I am done I make an animated GIF from these "process shots". I am trying to automatize the process and I have managed to come up with this which meets my needs:
#target photoshop
app.bringToFront();
// Stamp visible Layers
var idMrgV = charIDToTypeID( "MrgV" );
    var desc2 = new ActionDescriptor();
    var idDplc = charIDToTypeID( "Dplc" );
    desc2.putBoolean( idDplc, true );
executeAction( idMrgV, desc2, DialogModes.NO );
// Move Active Layer to the Bottom of LayerSet "process"
var activeLayer = activeDocument.activeLayer;
    var processFolder = activeDocument.layerSets.getByName("process")
    activeDocument.activeLayer.moveToEnd (processFolder);
Now I would like to add a conditional to check, whether or not the "process" layer-set exists and if it does not, create it. This should look something like this:
// Process Image Capture
// V 0.3
// PIC Stamps Visible (creates a new layer that combines all visible information in flattened form) and moves that to a "process" Layer Set.
// Layer is then hidden.
// If Layer Set is not there, it will be created.
#target photoshop
app.bringToFront();
// Check for "Process" Layer-Set on root. Create, in case it is not present.
if (!activeDocument.layerSets.getByName("process")) {
     activeDocument.LayerSets.add();
     activeDocument.LayerSets.name = "process";
/* else {
// Stamp visible Layers
var idMrgV = charIDToTypeID( "MrgV" );
    var desc2 = new ActionDescriptor();
    var idDplc = charIDToTypeID( "Dplc" );
    desc2.putBoolean( idDplc, true );
executeAction( idMrgV, desc2, DialogModes.NO );
// Move Active Layer to the Bottom of LayerSet "process"
    var activeLayer = activeDocument.activeLayer;
    var processFolder = activeDocument.layerSets.getByName("process")
    activeDocument.activeLayer.moveToEnd (processFolder);
    activeDocument.activeLayer.visibility = false;
The condition seems to be what causes the problem, but I have no idea how to fix it. Can somebody help?

Answer 1

Ok, here is the script that does the deed, it requires an additional function to catch what getByName() returns.
// Process Image Capture
// V 1.0
// PIC Stamps Visible (creates a new layer that combines all visible information in flattened form) and moves that to a "process" Layer Set.
// Layer is then hidden.
// If Layer Set is not there, it will be created.
#target photoshop
app.bringToFront();
// Check for "Process" Layer-Set on root. Create, in case it is not present.
if (!hasRootLayer("process")) {   
    var addedLayer = activeDocument.layerSets.add();
    addedLayer.name = "process";
// Stamp visible Layers
var idMrgV = charIDToTypeID( "MrgV" );
    var desc2 = new ActionDescriptor();
    var idDplc = charIDToTypeID( "Dplc" );
    desc2.putBoolean( idDplc, true );
executeAction( idMrgV, desc2, DialogModes.NO );
// Move Active Layer to the Bottom of LayerSet "process"
    var activeLayer = activeDocument.activeLayer;
    var processFolder = activeDocument.layerSets.getByName("process")
    activeDocument.activeLayer.moveToEnd (processFolder);
    activeDocument.activeLayer.visibility = false;
// Function to check whether "process" layer exists, passes result back as a boolean
    function hasRootLayer(layerName){
    var hasProcessLayer = false;
    try{
        hasProcessLayer = (typeof activeDocument.layerSets.getByName(layerName) != "undefined");
    }catch(e){}
    return hasProcessLayer;